Quiz
Renewable 2
Crie uma conta grátis para terminar este quiz
Salve seu progresso e veja sua nota final.
Já tem uma conta? Inicie sessão
Perguntas do quiz (200)
1What are advantages and disadvantages of the Fresnel lense over convencional lense?
- AFresnel lense is slimmer
- BFresnel lense is lighter (weight)
- CThe image quality of the fresnel lense is worse
- DThe fresnel lense cannot focuse the light
2Which stations are part of the eolic electric Energy production?
- AWind Energy
- BPower Network
- CSolar Energy
- DWater Energy
- ESolar panels
3What statements about Fresnel lens are true?
- AThe Fresnel lens reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections.
- BFresnel lens design allows a substantial reduction in thickness, mass and volume of material.
- CThey have an elliptical crossection
- DWere discovered in 1560 while Fresnel was researching in Paris
- EFresnel lens design increases the thickness, mass and volume of material of the lens
4Fresnel lens, compared to conventional lens:
- AAre cheaper
- BEven cheaper if they are polymeric
- CAre lighter
- DAre more difficult to handle
- EAre less stable
5The ESC:
- AIs an application of the fusion energy
- BHas no problems with the production of radiactive residues
- CHas minimal problems with the production of radiactive residues
- DNone of the others are correct
- EIs produced by the wind mills
- FIs an application of the fision energy
6Which mathematical function distribution arises when heating with focused solar beams?
- AGauss bell
- Bschottky circle
- Clopez-alonso quadratic
- Dfresnel ring
- Eczochralski hat
7The solar energy concentration...
- AIs being used for centuries
- Bcan be got by using lenses
- COnly reach 100 degrees
- DIs a new thing recently discovered
8Which of these sentences are true?
- ANatural materials occur because thery are in their stable form
- BGreenhouse is a way of solar energy concentration
- CLenses can be a way of solar energy concentration
- DThe natural materials are unstable
- ETo make an artificial material we have to give it energy in oder to make it stable
9In which of the following steps to obtain energy from the sun for a certain application there are losses of energy?
- AElectric energy production.
- BTransformation LV/HV.
- CGrid transportantion.
- DTransformation HV/LV.
- ENone of them are relevant, the losses are negligible.
10Which of the following statements are true?
- AGravitational, eolic, solar, biomass and chemical energy are natural ways to obtain energy.
- BAn Ellingham diagram is a graph showing the temperature dependence of the stability for compounds.
- CAubrey Eneas was able to water fields thanks to the solar energy.
- DIn a Linear Fresnel Installation the cleaning operations are easier than in a design of parabolic lens.
- ENone of the above answers are correct.
11Is it possible to achieve 1000ºC only using Solar Energy?
- AYes, it is
- BNo it isn't, This temperature is too high.
- CYes, it is. The solar panels work properly at temperatures until 1200ºC
- DNo, it isn't. The maximum temperature is 950ºC
- ENo, it isn't. The solar panels don't work properly at temperatures higher than 400ºC
12Which of the following gases contribute to the Greenhouse effect?
- AWater Vapor.
- BCarbon dioxide.
- CMethane.
- DOzone.
- EHelium
- FNitrogen Oxide
13which are the advantages of the use of Fresnel's design for lenses?
- ACleaning operations are simpler
- BLinearity means to eliminate the problem of the wind
- CIt can be realized with different materials
- DIt is faster to manufacture
- EIt is less cost sustainable
14Some advantages of a Fresnel lens vs a conventional lens are...
- Athey are cheaper
- Bthey are lighter
- Cthey are heavier
- Dthey are prettier
15Since solar energy was used for the first time, arround 2000 BC, several changes have been made in the solar panels in order to enhance the efficiency obtained, for example:
- AMirror surfaces have been improved so the reflectance is maximum and the shape is optimal to focus the radiation at a certain focal distance
- BDust on the surface can become a problem as it decreases the energy absorvance, which makes the cleaning of planar mirrors cheaper than for parabolic mirrors
- CSeveral configurations of solar stations have been developed depending on the characteristics of the landfild and the application of the station
- DCilindrical collectors are not efficient enough, so they are not used for comercial applications
- EMore robust structures have been developed in order to ensure that the wind will not deviate the mirror, which could decrease the efficiency of the solar panel
16When working with solar energy it is important to know that:
- AA parabolic mirror can be used for focusing the sun radiation in a spot
- BVery high temperature (2000ºC) can be reached by using mirrors
- CThe intensity of the sun radiation is different in Spain, Germany and El Salvador
- DThe intensity of the sun radiation only depends on the lattitude where the solar station is located
- EThe shadow of a cloud is important but it can be neglected when evaluating the thermal shock resistance of a material
17Some energies are:
- AGravitational
- BEolic
- CSolar
- DChemical y Biomass
- ENone of the above
18Which one is true?
- ALens were invented by Roger Bacon
- BEarl Buffon was able to concentrate 360 times the solar energy in a focus
- CThe current designs are very similar to the Schumann`s design
- DSchumann`design is a cone
- ENone of the above
19The use of concentrated thermal energy for materials productions is interesting because:
- AHigh temperatures (around 1500 - 2000K) can be achieved in few seconds (in the order of one or two minutes).
- BCoatings can be applied with no much diffusion
- CLet produce materials with high energy efficiency
- DIt is highly subsidized.
- EStable temperature conditions can be achieved for long periods of time
20Which of the following are utilities that can be given to a solar energy concentrator?
- ACoating of materials
- BWelding
- CThermal shock tests
- DGypsum dehydration
- EDirect conversion of solar energy in electricity
21Which of the following sentences are true?
- AMost metals in nature (stable state from the energetic point of view) are found in oxidezed form, so this is the reason why many manufactured metals tends to oxidize.
- BEllingham diagram is usually used to evaluate the ease of reduction of metal oxides
- CDecomposition or fracture growing are energetically favourable processes
- DSolar thermal energy cannot be stored.
22Some of the reasons to write a report are:
- AAnalize other report.
- BGiving guarantees to a client.
- CTo declare as an expert in a trail.
- DTo give some information about a specific topic.
- EFor solving some doubts for a work coleague
23About the part of the discussion
- ADiscussion must be simple and clearly elaborated.
- BReport body must include only elaborated data.
- CData must be presented better as a table, as a figure.
- DDetailed comments are sometimes better as a foot note.
- ENone of the above.
24In order to get a detailed subject description, it is convenient to identify clearly:
- ACause or origin.
- BFinal objective.
- CUltimate report recipient.
- DBoundary of the reports.
- ENone of the above.
25When some samples has to be sent for a report:
- AFor internal report, samples are sent by post mail
- BFor outside report, samples needs more formal sending
- CTrials reports needs certificates of sending and reception of samples
- DFor an internal report, samples needs more formal sending
- EFor trials reports, samples are sent by post mail
- FFor outside report, samples are sent by post mail
26About the sample collection:
- AIt is advisable to take pictures
- BIt should be done according to some standars
- CIt must include the surrounding area
- DIt have to be done by a police officer
- EIt is not a critical issue
27How can we know if our material is an ionic conductor and not and electron conductor from the plot Z'' vs Z'?
- AWe don´t have the electrode semicircle
- BWe don´t have electronic impedance
- CThe ionic impedance is zero
- DWe have 3 semicircles in the plot
28What is the reason why in SOFC Yttria stabilized Zirconia is combined with Nickel?
- ABecause while Nickel conducts electrons, YSZ conducts ions
- BBecause while Nickel conducts ions, YSZ conducts electrons
- CBecause is the way to obtain a cheaper CERMET
- DBecause otherwhise the Nickel is oxidized
- EThe other answers are not correct
29When designing a SOFCs cathode, which key factor would you expect in your material
- APossibility of different valence (oxidation) states, then ions of O- can flow through the electrolyte
- BHigh electronegativity
- CLow electron density
- DJust one valence state
- EAll correct
30How many parameters of a fuel cell can you measure with the impedance spectroscopy?
- A6
- B5
- C4
- D3
- E7
31When analysing the performance of a Fuel cell, impedance spectroscopy is used. Is it possible to distinguish between ionic and electronic conductivity with this technique?
- AYes, when electronic conductivity takes place there is no interface "pike" in the spectrum
- BYes, when ionic conductivity takes place there is an interface "pike" in its spectrum
- CYes, but there is no difference in the spectra obtained, so mathematic analysis are required.
- DYes, when electronic conductivity takes place there is an interface "pike" in the spectrum
- EYes, when ionic conductivity takes place there is no interface "pike" in its spectrum
32The physics behind an impedance spectroscopy measurement is represented by:
- AThe phasor diagram.
- BThe Ashby diagram.
- CThe stress-strain diagram.
- DThe Ellingham diagram.
- EThe flowchart (diagram of a process).
33What is the most highly developed design of fuel cells which has several advantages such as easy-sealing and mechanical strength due to its structure?
- ATubular-type.
- BPlanar-type.
- CPentagonal-type.
- DPyramidal-type.
- ECubic-type.
34the anode of Solid Oxide Fuel Cells could be made of yttrium established zirconia with Ni in order to allow oxigen and electrons to pass through.
- AYes, it is a good choice
- Bno, Ni does not allow the electrons to pass
- Cno, yttrium established zirconia is an insulating plastic
- Dno, Ni is an insulating metal
- Eall the answers are true
35The main method of electron conductivity in LaMnO cathode is...
- AElectron hoping carried out by Mn3+ and Mn4+
- BElectron tunneling carried out by La3+ and Mn4+
- CElectron tunneling carried out by La3+ and La4+
- DElectron tunneling carried out by O3+ and O4+
- EElectron hoping carried out by Mn3+ to O4+
36If to the compound LaMnO3 we add Sr, the ceramic material decompensates (from the electrical point of view). Mark as true the possible compesation mechanisms:
- AOxidation.
- BOxygen vacancy.
- CReduction.
- DManganese vacancy.
- EAll the answers are false, Sr cannot be added to LaMnO3
37Application of a voltage to a solid material
- AElectrical current flow
- BIon conductivity
- CNo charge flow
- Dinsulating materials, usually there is a big leakage current though
- ENon-metallic type conduction
38The impedance of an ideal resistance:
- AHas only real part.
- BHas real and imaginary part.
- CHas only imaginary part.
- DHas only real part as for ideal inductors and capacitors.
- EHas only imaginary part as for ideal inductors and capacitors.
39About Brick Work Layer Model
- ABulk, GB and electrode areas behave differently, so the different RC elements can be distinguished
- BNot uniform grain boundary
- CElectrode and bulk cannot each be represented by ONE RC element
- DNon- homogeneous distribution of grain sizes
- EWide distribution of grain sizes
40Possible results of an aplication voltage to a solid material
- AElectrical current flow, Ionic conductivity and no charge flow
- BYou can not know it.
- CAll of them
- DNone of them
- EIt changes the shape
41When we apply a voltage to a solid material, which of the following results can we obtain?
- AMetal-type elctronic conductivity
- BSemiconductor-type electronic conductivity
- CIon conductivity
- DNo charge flow, i.e. we are facing an insulator
- ENone of the above
42The possible results of the application of voltage to solids...
- AElectrical current flow
- BIonic conductivity
- CNo charge flow
- DIsolating flow
- Enone of the others
43Which of the following sentences is correct about Batteries?
- ASolid electrolyte, cathode and anode materials are usually polycrystalline materials
- BIn ionic conductors, grain boundaries act as barriers for ionic charge transport.
- CSolid electrolyte, cathode and anode materials are usually monocrystalline materials
- DSolid electrolyte, cathode and anode materials are usually amorphous materials
- ENone of the others are correct
44When applying a voltage to a solid material, what are the possible results?
- Ametallic type conduction
- BIonic conductivity
- CNo charge flow
- Dsemiconducting type conduction
- Emetallic type isolation
45The Brick Work Layer Mode considers...
- AUniform grain boundary, electrode and bulk properties
- BUniform grain boundary, and bulk properties
- COnly bulk properties
- DNo electrode
- ENot uniform grain boundary and bulk properties
46The possible results of the application of a voltage to a solid material are:
- AElectrical current flow
- BIonic conductivity
- CNo charge flow
- DIt is impossible to apply voltage to a solid material
- EAll of them are true
47what can be expected by applying a voltage to a solid material?
- Aelectrical flow
- Bionic conductivity
- Cno charge flow
- Dneutron flow
- Ewith voltagemeter measured photon flow
48What is measured with impedance spectroscopy?
- Athe real resistance.
- Bthe imaginary resistance
- Cthe datas are measured with diffirent frequencies
- Dthere are several measurements at different temperatures.
- Ethe frequency depending on the temperature
49Which of the followings are real SOFC?
- APEM
- BMCFC
- CAFC
- DAPT
- EMOFC
- FPTM
50Which materials are used in solid oxide fuel cells and why?
- ANi for electronic conduction in the anod
- BZrYO for ionic conduction in the anod
- CNi for ionic conduction in the cathod
- DCu for electronic conduction in the anod
51What is the main inconvenient about Lead-Acid batteries?
- ALead is very toxic
- BLead is a too heavy material
- CLead is difficult to be recycled
- DAcid is very toxic
- EThey are the heaviest batteries
52Which is THE MAIN criteria to accept a battery design properly for domestic applications?
- AThe temperature dependence
- BAll answers are false
- CThe toxicity
- DDurability
- EElectrolite used
- FRechargeability
53Is it possible to develope Na batteries?
- AYes, and they are cheaper than Li batteries because Na is more available on Earth crust
- BYes, but they must be used at temperatures of 60-80ºC
- CYes, but they are not suitable for domestic applications
- DYes, and they but they are cheaper than Li batteries although Na is a scarce material on the Earth crust
- EAll answers are correct
54Some selection criteria for battery materials are:
- APrice.
- Benvironmental issues for battery disposal.
- CNumber of chargign/dicharging cycles.
- DOperating temperature.
- ENone of the above.
55The main physical parameters of batteries are:
- ASpecific power.
- BSpecific energy.
- CEnergy density.
- DCapacity.
- ENone of the above.
56Wich of the following sentences is correct about PEM fuel cell?
- AOperationg Temperature of PEMFC is between 80-100 C
- BEfficiency is about 40-50 %
- CA disadvantage is that needs pure H2 gas
- DA disadvantage is that is CO sensitive
- EOperationg Temperature of PEMFC is between 800-1000 C
- FEfficiency is about 60 %
- GA disadvantage is that the slow heating process
57Which of the following sentences are correct about fuel cells?
- AOperationg Temperature of SOFC is between 800-1000 C
- BEfficiency is about 60 %
- CThe main disadvantage is that needs high operating temperature
- DThe electrolyte is YSZ ceramics
- EOperationg Temperature of SOFC is between 600-800 C
- FEfficiency is about 75 %
- GNone of the others are correct
58Which of the next fuel cell can get 80 % efficiency?
- ASolid oxide fuel cell
- BProton exchange membrane
- CMolten carbonate fuel cell
- DAlkaline fuel cell
- EDirect methanol fuel cell
59How the thermal energy required is obtained for operation of SOFCs
- ADue to the high exothermal reaction in the Anode
- Bdue to the high exothermal reaction in the catode
- Cdue to the high endothermal reaction in the catode
- Ddue to the high endothermal reaction in the anode
- EApplying an external bias
60Some applications for the fuel cells are...
- AClean Energy
- BVehicles
- CSolar panels
- DAll of them
- ENone of them
61In an alkaline fuel cell...
- Athe operating temperature is 60-80ºC
- Bthe operating temperature is 60-80K
- Cwe can have an efficiency up to 80%
- Dwe have very quick chemical reactions
- Enone of the others
62Some criteria for choosing battery materials are:
- APrice and the capability of easy manufacture
- BNumber of charging/discharging cycles
- COperating temperature
- DEnviromental issues
- EWater resistance
- FExplosive power
63Why Na fuel cells are being researching for substituing fuel cells containing Li?
- ANa is cheaper than Li
- BNa is easier to obtain
- CNa works like Li
- DNa fuel cells could have 100 times Li fuel cells capacity
- EThe other answers are not correct
64In Solid Oxide Fuel Cells (SOFCs), using a steam turbine, the efficiency increases by:
- A15 - 20%.
- B50%.
- C5%.
- D100%.
- EThe efficiency does not increase.
65Some of selection criteria for battery materials are:
- APrice and easy fabrication.
- BEnvironmental issues for battery disposal.
- COperating temperature.
- DHigh efficiency during charging/discharging.
- EColor and smell.
66Which of these options are alternatives to Solid Oxide Fuel Cells (SOFCs)?
- AMolten Carbonate Fuel Cell MCFC)
- BAlkaline Fuel Cell (AFC)
- CDirect Methanol Fuel Cell (DMFC)
- DPolymer Electrolyte Membrane Fuel Cell (PEMFC)
- EFluoridric Acid Fuel Cell (FAFC)
67Which of the following sentences is correct when talking about Proton Exchange Membran Fuel Cell (PEMFC)?
- ASomeone refers to it also as Polymer Electrolyte Membrane Fuel Cell
- BHydrogen ions are moving
- CIt is an alternative to Solid Oxide Fuel Cell (SOFC)
- DThe electrolyte is a ceramic as in SOFCs
- EWe can use a steam turbine as in SOFCs to increase the efficiency because the operating temperatures are so high
68A Solid oxide fuel cell has a ..
- AYSZ electrolyte
- BPolymer electrolyte
- CAcid electrolyte
- DDoesnt have electrolyte
- EAll are false
69What are selection criteria for the battery material?
- AOne Point is the price, and an easy fabrication
- BThe number of charging and discharging cicles is very important
- CEnvironmental issues for battery disposal is another point (for example lead is bad)
- Dthe Operating temperature, and the temperature dependence of the physical parameters of the battery
- EThe design of the material is very important
70What are the Operating Temperatures of different Fuel Cells?
- ASOFC: 800 to 1000 °C
- BPEM: 80 to 100 °C
- CMCFC: 650 °C
- DPAFC: 200 °C
- EAFC: 600 °C
- FDMFC: 800 °C
71How can you improve the efficiency of a SOFC?
- AWith a steam turbine
- BOperating at lower temperature
- COperating at higher temperature
- DUsing a polymer electrolyte
- EThe efficiency cannot be improved
72What are the similarities between solid oxide fuel cells and proton exchange membrane fuel cells?
- AOxygen and hydrogen are incoming elements and water is released.
- BIn both cells the electrolyte is the efficiency limiting factor
- CThe theoretical potential of the cell (E_0) is the same for both cells and around 1.2 V
- DFuel cell efficiency could be improved using steam turbines
- EThe electrolyte is the same.
- FElectron flow is in the same direction as the ion flow
- GThe electolyte is a polymer
73If you are looking for a high specific energy, the battery should have...
- Ahigh power
- Blow mass
- Chigh life time
- Dlow power
- Ehigh mass
74Which of the following statements about SOFC electrolyte are true?
- AIt should be O2- conductor but electron insulator
- BIt is usually the limiting factor of the SOFC
- CEfficiency is about 60% and can be improved to 75-80 % using steam turbine.
- DIt should be O2- conductor and electron conductor as well
- EOperating temperature is from 30 to 100 celsius degrees
75If you want to miniaturize a battery, which of the next parameters is/are the important one/s?
- AEnergy density
- BSpecific power
- CSpecific energy
- DCapacity
76Select those statment about Fresnel Lenses that are correct:
- AAre less expensive than other lenses
- BAre made of glass or plastic
- CReduces the amount of material needed compared to a convential lens
- DFresnel lens design allows a substantial reduction in thickness
- EAre usually heavier than other kind of lenses
- FNone of the others are correct
77Which of these sentences are true?
- ATo make an artificial material we have to give it energy in oder to make it stable
- BNatural materials occur because thery are in their stable form
- CGreenhouse is a way of solar energy concentration
- DLenses can be a way of solar energy concentration
- EThe natural materials are unstable
78Fresnel lens are made of...
- Aglass or plastic.
- BAlways glass
- CAlways plastic
- DA polished metal
79Buffon was a member of the aristocracy and he used concentrated solar energy to...
- ABurn wood
- BHeat his palace
- CMake water evaporate
- DWin battles
- ENone of them
80Which of the following stages is present in the electric alternative to supply energy and is not present in the chemical alternative?
- AGrid transportation
- BSolar energy
- CReceiver
- DAir heating
- EFurnace or reactor heating
81Which are those materials to which has been given some energy and are in unstable or metastable condition?
- AArtificial material
- BAll ceramics and metals
- CAll polymers and metals
- DAll materials are in metastable state
- ENatural and biologic materials
82How to criticize another report?
- AWere properly identified the material?
- BWas adequate the level of confidence?
- CWere experiments properly acreditated?
- DTest were made according to a stablished standars?
- ENone of the others are correct
83Is the Director (last sign in the report) the maximum responsible of the report?
- ANo he isn't, this person could have no idea about the objectives of the report
- BNo he isn't, this is a process sign, it is without responsability
- Cyes he is.
- Dyes he is. He is the maximun legal person that sign it
- EYes he is. He is the Director.
84The annexes can include:
- ANot relevant but interesting data.
- BAdditional certifications.
- CLiterature references.
- DSample collection pictures.
- EIn a technical report, annexes are not allowed.
85Which are more important points on sample collection?
- AHow the sample has been taken, because the sample could have been modified in the process.
- BIf the sample has been properly obtained following the protocol.
- CWho take the sample: is the person an expert in the matter or not?
- DHow much representative the sample is.
- EIt does not matter the person who obtained the sample and anyone, not expert in the problem, could take it.
86The general scheme of a report must include...
- AConclussions
- BDiscussion
- CAnnexes
- DAnalysis and related tests
- EOur curriculum and the list of publications we have made
87When writing a report it is important...
- ATo know who will read the report, because the outlook might change
- BBeing paid for the expenses in advance
- CThat it would be better to present the data as a table or figure than a text
- DTo argue properly which our personal opinion is, so the judge will know easily what happened and will be able to decide who will go to jail
- EThat the owner of the report cannot say anything about the report
88Why would someone ask for a report?
- ATo analyze another report
- BTo know something about
- CTo give guarantees to the client
- DTo declare as an expert in a civil or crimical trial
- EReports are not a useful tool
89The "detailed subject description" should contain...
- Aa summary
- Bboundaries of the report
- Ca description of the techniques we have used
- Dgreetings from the author
- Enone of the above
90Who is the owner of a report
- AJust the person that orders it and pay for it
- BThe author
- CThe judge
- DThe person that orders it and pay for it and also the author
- EAny of the other answers is correct
91Why to analyze other reports is important in order to do a good report
- AIt is the cheapest option for obtaining experience and information
- BIt is a good option for knowing typical errors
- CIt could save us time
- DIt is established by law
- EAny of the other answers is correct
92Which of the following aspect must not be included in annexes?
- ARelevant data
- BSupply samples certifications
- CNo relevant but interesting data
- DAcreditations, homologations,
- EAdditional certifications
93What are the first things we have to identify when we write a technical report?
- Aits final destination
- Bthe demanding person
- Cthe samples we own
- Dreasons why the client asks for the report
- ENone of them
94When you are in the middle of a judicial hearing, what do you have to do?
- Atry to convince the judge
- Bfight with the counterpart lawier
- Ctry to convnice the audience
- Dshout at the suitor
- Enone of them
95What is it convenient to identify clearly in the report?
- AFinal objective
- BSubjects excluded and why
- CSamples origin
- DConclussion with the technical results
- EConclussion with a final accusation
- FAll answers are correct
96Why we ask for a report?
- ATo analyze another report
- BTo know someting about
- CTo give guarantees to the client
- DTo declare as an expert in a civil or criminal trail
- EAll the answers are incorrect
97When you are going to elaborate a technical report....
- AIt is important to use standars
- BYou should use accredited laboratory equipments in order to avoid criticism
- CYou must bear in mind that the "client" has the rights to the report
- DIt does not matter who has performed the sample collection
- ESignature of the head department is as important as yours
98A technical report should contain the next main parts:
- APresentation, discussion, conclussions and closing remarks.
- BDetailed description of the subject
- CInformation related to the samples
- DAnalysis and related tests
- EAnnexes to deal with irrelevant themes like the boundaries of the report and/or smaple collection and preparation
- FAll answers are correct.
99When you take a sample without follow any standard, you have to...
- ASpecify in your report all the variables that have to be taking into account in order to take the samples (Machinery, procedure...)
- BChoose the standard that best fits with your procedure and say that you almost has follow this standard in your report
- CIs not an important issue to follow any standard
- DJust mention in your report that you did not follow any standard
- EJust specify the machines that you have used
100You are criticizing an external report to write a second report , and you notice that the author is not expert in the matter. Which of the following procedures you have not to follow in your report?
- ATo be derogatory
- BQuestion the professionalism of the author
- CTry to discredit the author
- DDisrespect the author
- ERemark that the author is not expert regarding his CV.
101About Li ion batteries which answers are true:
- ALi is placed between graphite sheets
- BCan be charged
- CIs never safe of explosions
- DIs not suitable for electrical devices
- ECan not be charged
102In Solid Oxide Fuel Cells, the electrolyte must be
- AElectrically insulator and O2- ion conductor
- BElectrically conductor and O2- ion insulator
- CBoth Electrically and O2- ion insulator
- DBoth Electrically and O2- ion conductor
- EAlways conductor
103Which are parameters that characterize batteries?
- ASpecific porwer
- BEnergy density
- CCapacity
- DEquivalent hidrogen
- ESpecific self-healing factor
104Which of the followings are selection criteria for battery materials?
- ALow price and easy fabrication
- BLittle self-discharge
- CHigh number of charging/discharging cycles
- DHigh efficiency
- ELow number of charging/discharging cycles
- FHigh temperature dependance
- GNone of the others are correct
105does voltaje depend on the size of the cell?
- ANo, it does't. Voltaje only depends on the meterials in cathode and anode
- BNo, it does't. Size means the amount of energy that the cell could store
- CYes, it is. The larger is the cell the higher is the voltaje
- DNo, it does't. Size is related to the colour of the cell
- EYes, it is. The smaller is the cell the higher is the voltaje
106What are the problems with lithium ion batteries?
- ALi is comparatively rare element
- BLi must be purified to at least 99,95% purity
- CThey are expensive
- DLithium is not stable by itself
- EThe Li potential is low
107Which are the main characteristic of a battery electrolyte?
- AIonically conducting.
- BElectronically insulating.
- CElectronically conducting.
- DIonically insulating.
- EThe same characteristics as the anode and the cathode.
108Which are the three fundamentals components of a battery?
- AThe negative electrode (anode), the positive electrode (cathode) and the electrolyte.
- BThe negative electrode (cathode), the positive electrode (anode) and the electrolyte.
- CThe negative electrolyte (anode), the positive electrolyte (cathode) and the electrode.
- DThere aren’t three components, only two: anode and cathode.
- EThere are four basic components: negative electrode, positive electrode, negative electrolyte and positive electrolyte.
109Solide Oxide Fuels Cells
- AAre also called SOFC
- BAre rechargeable
- CAre not suitable for car batteries as they may require to have a bottle of H2 to recharge, which can be dangerous to transport
- DAre based on the transporting ions through a ceramic material
- EUse concentrated solutions as medium for transporting the electrolyte
- FCannot be made of Lithium as it is a scarce material
- GWere invented before than the galvanic cell
- HNowadays are suitable for car batteries as it is a very clean energy and you only need water to refill the battery
110In a galvanic cell design it is important to know...
- AThe electromotive force mainly depends on the materials used for the Redox reaction
- BThe standard electrode potential of the materials used
- CThat gas materials can be used as well
- DThe oxidation takes place in the anode
- EAny combination of two materials can result profitable for producing electricity
- FRedox reactions are not reversible
- GCars batteries cannot be made by galvanic cells
- HThat the oxidation takes place in the cathode
111The elecrolyte in Solid Oxide Fuel Cells (SOFC)...
- A...is solid and normally consists of ceramic materials
- B...has to let oxygen anions pass through
- C...has to be electrical insulator
- D...is very easily produced
- E...has to be intermixed with cation and anion
112Which of the following sentences about Lithium batteries are true?
- AThey are currently the most used ones and they are rechargeable
- BThey have the problem of Li catching fire
- CGraphite is used in order to store Li
- DCathode consists of a ceramic material containing metals with different oxidation numbers
- ELi is an abuntant element on Earth crust
113The nickel–cadmium battery....
- Ais rechargeable.
- Bcadmium electrode oxidizes.
- Cuses nickel oxide hydroxide and metallic cadmium as electrodes.
- Duses metallic nickel and cadmium electrodes
- Ecannot be re-charged.
- Fis a new type of battery that will be started to use next years
114In the Daniell cell, copper and zinc electrodes are immersed in a solution of CuSO4 and ZnSO4 respectively. Which of the next sentences about Daniell Cell are true?
- AThe open-circuit voltage that can be obtained is around 1.1 V
- BAt the anode, Zn is oxidized (release electrons) and at the cathode, Cu is reduced (absorb electrons).
- CDaniell cell converts chemical energy to electrical energy and the change in Gibbs free energy is lower than zero.
- DElectrons move from the Cu electrode to the Zn electrode.
- EDaniell cell converts chemical energy to electrical energy, and the process is non-reversible.
- FAt the anode, Cu is oxidized (release electrons) and at the cathode, Zn is reduced (absorb electrons)
- GDaniell cell is reversible if you apply the enough EMF and the electrodes recover the initial shape.
115In a Daniel cell...
- AThe anode is oxidized
- BThe cathode is reduced
- CThe anode is made of Zn
- DThe cathode is made of Cu
- EThe anode is reduced
- FThe cathode is oxidized
- GThe anode is made of Cu
- HThe cathode is made of Zn
116What are the principal elements of a galvanic cell?
- AAnode
- BCathode
- CElectrolyte
- DVessel
- EVoltimeter
117Choose the correct selection criteria for battery materials:
- APrice
- BHigh capacity
- CNumber of charging/discharging cycles
- DAbsence of temperature dependance
- ELow capacity
118Which of the followings are important physical parameters for batteries?
- ASpecific power
- BSpecific energy
- CCapacity
- DHardness
- EColor
119For the selection criteria for battery materials you should consider:
- APrice
- BNumber of charging/discharging cycles
- COperating temperature
- DThermal potential
- ESpecific Heat
120Select the correct:
- AFor Lithium ion batteries the electrolite is a Potassium/caustic soda solution
- BFor solid oxide fuel cell the electrolyte is a ceramic
- CThe specific power is voltage*mean current
- DSpecific energy is equal to voltage
- ECapacity of batteries is maximum voltage*time
121What of those sentences are true?
- AA battery works through redox reduction.
- BOne of the first battery used Zn and Cu
- CFuel cells uses the heat producted in a chemical reaction to produce electrical energy.
- DAll the batteries uses hydrogen gas.
- EFuel cells and batteries are the same thing.
122Regarding the Daniels Cell, select the right statements
- AAt the cathode, copper is reduced
- BAt the anode, zinc is oxidized
- CIons flow across the porous barrier
- DAt the anode, zinc is reduced
- EAt the cathode, copper is oxidized
123Which criterias are used to select battery materials?
- Aprice, easy fabrication
- Blittle self-discharge
- Cnumber of charging/discharging cycles
- Denvironmental issues for battery disposal
- Ecolor of material
- Fnone of them are correct
124Reaction elements of a solid oxide fuel cell:
- Ahidrogen
- Boxigen
- Cmethanol
- Dcarbon trioxide
- EYSZ
125what do you need yo create a standar hydrogen cell?
- AHydrogen
- BMetal
- C2H3O+
- DZinc
- ECopper
126Which of the following statements are true for Lead Batteries?
- AThey have are very efficient
- BThey are very toxic
- CThey are not toxic
- DYou can eat them
- EThey are not efficient
127About the electrolyte in Solid Oxide Fuel Cells (SOFC)...
- AIt has to let oxygen anions pass through.
- BIt is a electrical insulator.
- CIt is solid and normally consists of ceramic materials
- DIt has the same characteristics as the anode and catode.
- EIt is a conductor, that way electrons can pass through.
128Which of the following statements about lead bateries are true?
- ALead is very toxic
- BLead bateries are the ones used in cars
- CWe can obtain larger voltages by putting the bateries in series
- DLead bateries are the ones used in trains
- ELead is not very toxic
- FWe can obtain larger voltages by putting the bateries in parallel
129Which of the following statements regarding SOFCs are true?
- ATheir operating temperature is around 800-1000 ºC
- BTheir efficiency can be improved by combining with a turbine gas
- CTheir efficiency is quite low (35-40%)
- DTheir operating temperature is not a disadvantage
130Choose the range temperature and the efficiency for Solid oxide fuel cells:
- A800-1000 ºC
- B60% efficiency
- C80% efficiency
- D600-800 ºC
- E70% efficiency
- F400-600 ºC
131Which of the followings are types of fuel cells under research?
- ASolide oxide fuel cell
- BProton exchange membrane fuel cell
- CMolten carbonate fuel cell
- DAlkaline fuel cell
- EGalvanic fuel cell
- FHydrogen standard fuel cell
132Which of the following corresponds to a Proton Exchange membrane?
- AOperating temperature , 80-100 °C
- BEfficiency of about 40-50 %
- CEfficiency of about 90 %
- DOperating temperature , 25°C
- ENone of the above
133For the Solid oxide fuel cell:
- AOperating temperature: 800 - 1000 °C
- BEfficiency with steam turbine: 75 – 80 %
- CEfficiency: 60 %
- DEfficiency: 80 %
- EOperating temperature: 1000 - 1200 °C
134Wich are the disvantages of Molten carbonate fuel cell?
- ASlow heating process
- Blong start-up
- CCO2 separation
- DSlow chemical reactions
- ECO2 exhaust
135Which are the parts of a tubular solid oxide fuel cell?
- ACathode and anode
- BBuffer.
- CElectrolyte.
- DNi felt.
- EPolymer support.
- FAu or Pt bridge between the anode and the cathode.
136Criteria for battery materials:
- AElectrode potential, specific power, specific energy, capacity.
- BOperating temperature, temperature dependence.
- CEnvironmental issues for battery disposal.
- DPrice.
- EMagnetic properties.
- FHight elastic limit.
- GHigh impact absorbance.
137Select the correct
- AIn solid oxide fuel cell the efficiency is around 60%
- BIn PEM fuel cell efficiency is 40-45%
- CIn DMFC efficiency is 40-50%
- Din MCFC efficiency is around 55-60%
- EDMFC has the highest efficiency
- FPEM is the acronym of Powder Electrolyte Membrane
138Which of the following sentences is correct about PEM fuel cell?
- AOperating temperature of PEMFC is between 80-100 C.
- BEfficiency is about 40-50 %.
- CA disadvantage is that needs pure H2 gas.
- DA disadvantage is that is CO sensitive,
- EOperating Temperature of PEMFC is between 800-1000 C
- FEfficiency is about 60 %.
139What are the request for the materials composing a SOFC?
- AAnode must be porous.
- BCathode must be porous.
- CElectrolyte must be dense.
- DCathode must be dense.
- EElectrolyte must be porous.
140Regarding Solid Oxide Fuel Cells, select the right statements
- Ais an electrochemical conversion device that produces electricity directly from oxidizing a fuel
- BFuel cells are characterized by their electrolyte material
- Cthe SOFC has a solid oxide or ceramic electrolyte
- DThe electrolyte is a light layer of ceramic
- EThe electrolyte in SOFC conducts both electrons and ions
141What is the reason why some AA batteries are rechargeables and another ones are not?
- AIt is due to the internal membrane, which allows the flow just in one dirrection in non rechargeable batterys and allows the flow in the two directions in rechargeable cases.
- BIt is due to the internal membrane, which allows the flow just in one dirrection in rechargeable batterys and allows the flow in the two directions in non rechargeable cases.
- CIt is due to the composition of the battery
- DIt depends on the country you bought them
- EAll the other answers are not correct
142What are the most common fuel cells?
- ASolid oxide fuel cell
- BProton exchange membrane fuel cell
- CMolton carbonate fuel cell
- DAlkaline fuel cell
- ESilika fuel cell
- FNone of them are correct
143What are the different requirements for the parts in a SOFC?
- AElectrolyte: Oxygen-ion-conductivity; electron insulator
- BAnode: electron conductivity; Oxygen-ion-conductivity
- Ccathode: electron conductivity; Oxygen-ion-conductivity
- DElectrolyte: hydrogen-ion-conductivity; electron conductor
- Eanode: electron insulator, hydrogen-ion-conductor
144Which of the following metals are noble?
- AGold (Au)
- BSilver (Ag)
- CPlatin (Pt)
- DCinc (Zn)
- EFalse answer 2: elementary iron (Fe)
145vehicles with ability to use fuel cells
- Atrains
- Bcars
- Ctrucks
- Dplains
- Ebikes
146A galvanic cell is a device...
- AIn which anode oxidizes
- BIn which cathode reduces
- CIn which cathode oxidizes
- DIn which anode reduces
- EIn which the voltage only depend on the shape and size of the materials used
147In a PEM fuel cell...
- AThe operating temperature is between 80-100ºc
- BThe efficiency is between 40-50%
- CYou need pure H2
- DThe operating temperature is between 40-60ºc
- EThe efficiency is between 70-80%
148The main characteristic of a noble metal is....
- Ait do not oxidize
- Bit has a positive potential with regard hydrogen
- Cit oxidize very easy
- Dits unique application is batteries
- Ehas a special oxidation layer
149About noble metals...
- Athey do not oxidize easily
- Bsome of them are Au, Pt, Cu...
- CFe is one of them
- Dthey are not used in hydrogen cells
- Enone of the others
150Which of the following fuel cells don't obtain carbon dioxide as products?
- ASolid oxide fuel cell
- BProton exchange membrane
- CAlkaline fuel cell
- DDirect methanol fuel cell
- EAll the fuel cells are clean
151Li is used in anodes for batteries because...
- Ait has the most negative potential out of the solids
- Bit is so electronegative
- Cit is very cheap
- Dit is easily found in nature
- Enone of the others
152In a hydrogen standard cell...
- AHydrogen will oxidize and metal reduce if metal has a possitive potential
- BHydrogen will reduce and metal oxidize if metal has a negative potential
- Cmetal will oxidize always
- DHydrogen will reduce and metal oxidize if metal has a negagtive potential
- Enone of the others
153Which of these sentences are true?
- AAg is a noble material
- BA noble material is a material hard to oxidize
- CPt is one of the materials most difficult to oxidize
- DOxidiation and reduction is the basis of batteries
- EAu is not a noble material
154Electrophoretic deposition (EPD) means the combination of (2)processes:
- Aelectrophorosis
- Bdeposition
- Cmagnetophoresis
- DCVD
- ELithography
- FEtching
155Advantages of the sol-gel process:
- AHigh purity.
- BHigh homegeneity.
- CWide range of composites.
- DLow temperature synthesis and processing.
- ENone of the above.
156About Sol-gel process
- ASol-gel process allow performing, at low temperature, ceramic and glass materials with high purity levels.
- BThe motivation for sol-gel processing is associated to the higher purity.
- CThe lower processing temperatures related to chemical process compared with traditional glass melting or ceramic powder
- DThe motivation for sol-gel processing is not associated to the homogeneity
- ENone of the above.
157What do we neeed to control in order to avoid cracking in sol-gel process?
- AEvaporation rate
- BVapor solvent pressure
- CPore diameter
- DSurface deffects
- EColour
158Is Sun-Gel process a good choice for corrosion protection?
- AYes, but it is not the cheapest option
- BYes, it is. The quality of the coating is quite good
- CNo it isn't. This method is not used for coatings
- DYes it is. This wood is a good option for coating process
- ENo it isn't.
159Sol-gel synthetized materials can have several applications such as:
- AAnticorrosive coatings which can be made by Sol-Gel + Electrophoretic Deposition
- BBactericide
- CAntiadhesive coatings and self-cleaning surfaces
- DDrug-delivery
- EAll answers are correct
- FSol-gel synthesis is not useful to obtain photocatalysts
- GSol-gel synthetized products cannot be used for medical applications because the material obtained won't be biocompatible
- HAll answers are false
160Several parameters must be considered when designing a sol-gel synthesis:
- AIf we want to obtain large polymers, an acid pH should be used
- BThe ratio H2O:precursor affects to the gellification time, among others
- CSynthesis must be designed carefully, otherwise shrinkage could take place when drying the gel
- DIf we want to obtain isolated and small polymers, a low pH should be used
- EGel density only depends on the amount of precursor involved
- FThe drying time cannot be controlled, it only depends on the water concentration, precursor used and the pH
161What are the main advantages of the Sol-Gel process?
- AHigh purity
- BHigh homogenity
- CWide range of compositions
- DAdequate process for thin coatings
- ELow price of raw materials and chemicals
- FHigh gelling rate
- GLow cracking in bulk samples
162About Sol-Gel synthesis:
- AHigh temperature are not required fot synthesis
- BIs it possible to achieve ceramics and glass materials with high purity levels
- CHigh temperature are required fot synthesis
- DIs it possible to achieve ceramics and metallic materials with high purity levels
- ENone of the others are correct
163Typical applications of the sol gel process are...
- ACoatings
- BDrug delivery systems
- COrganic solar cells
- DManufacturing of very big components
- EManufacturing of very thick components
164Which are the advantages correlated with the sol-gel process?
- AIt is a low temperature process
- BWe can choose between two routes of process
- CIt is easy to control all the parameters of the process
- DIt is easy to control all the rates of reactions occurring
- ENormally the precursor used in one of the routes are low cost
165The sol-gel process...
- Aallows performing, at low temperature , ceramic and glass materials with high purity levels
- Ballows performing, at high temperature , ceramic and glass materials with high purity levels
- Callows performing, at low temperature , ceramic and glass materials with low purity levels
- Dallows performing, at high temperature , ceramic and glass materials with low purity levels
- EAll false.
166Which of the next statement about sol-gel technique are true?
- ANowadays, metal alkoxides are the main precursors
- BDrying process is typically accompanied by shrinkage, which could produce cracking
- CCoating is an important applications of sol-gel process
- DAll the other statements are false
167The sol-gel process....
- AIs a method for producing solid materials from small molecules.
- Ballows obtaining bulk materials but with small dimensions
- Callows manufacturing ceramic and glass materials wiht high quality but under high temperature conditions.
- DThe unique motivation for sol-gel process is energy saving.
- EBulk materials cannot be otbained. Sol-gel technique is only used for coatings.
168What materials performed by the sol-gel process show high density and low sintering temperature?
- AHybrid inorganic-organic materials.
- BInorganic materials.
- CPolymeric materials.
- DCeramic materials.
- EMetallic materials.
169Which are some of the main advantages of the sol-gel process?
- AHigh purity and homogeneity (molecular level).
- BWide range of compositions.
- CLow temperature synthesis and processing.
- DAdequate process for thin coatings.
- EHigh price of raw materials and chemicals.
- FLow gelling rate and cracking in bulk samples.
170Usually, sol-gel with acid pH have:
- AVc>>Vh
- BLong linear chains
- CVh>>Vc
- DShort ramificated chains
- EHigher refraction index
171In the Gel-glass transition, the catalysis could be acid or basic. What of them gives a material with higher density?
- AThe Acid catalysis
- BThe Basic catalysis
- CAlways the one that occurs at higher temperature
- DAcid or Basic catalysis, the density does not depends on the catalysis type
- EAlways the one that occurs at lower temperature
172What is the most important step in Sol-Gel process?
- AAll the steps are important in order to obtain a Sol-Gel with good properties
- BThe Sol-Gel transition
- CThe Gel-glass transition
- DThe drying and shaping
- EThe sinterization
173Regarding the production of a sol by mean of a precursor, which of the following statements are true?
- AUsing basic PH you will obtain isolated and small polymers.
- BUsing acid PH you will obtain large polymers.
- CUsing acid PH you will need less temperature in sintering process.
- DIf the concentration of H2O is big enough you will obtain a close result to using acid PH.
- EUsing acid PH you will obtain isolated polymers
174Which of the following are the names of the routes used to obtain ceramic material by sol-gel process?
- AColloidal route
- BAlkoxide route
- CElectrophilic attack route
- DAdiabatic route
- EHydrolytic route
175Which of these sentences are true?
- ASol - gel process allows performing, at low temperature, ceramic and glass materials with high purity levels
- BSol - gel process allows performing, at low temperature, ceramic and glass materials with low purity levels
- CSol - gel process does not allow performing, at low temperature, ceramic and glass materials with high purity levels
- DSol - gel process allows performing, at low temperature, just glass materials with high purity levels
- ESol - gel process allows performing, at low temperature, just ceramic materials with high purity levels
176Sol-gel process allows...
- Aoperating at low temperature
- Bperforming ceramic materials
- Chigh purity levels
- Dperforming glass materials
- ENone of the others
177Which of these steps form part of ceramic processing?
- Ahomogenization
- Bshaping
- Cdrying
- Dsintering
- Enone of them
178a Pourbaix diagram..
- Amaps out possible stable (equilibrium) phases of an aqueous electrochemical system
- BIt can help us with corrosion problems
- CPlot pH versus potential
- DIt is a specific phase diagram of Cu-Ni
- EThe first one was discovered 9 years ago
179Why controlling sub-critical conditions?
- AGive very high processing quality
- BNo influence
- CThe particles are dissolved
- DThermodynamics does not allow processing nearby critical point
- EThe processing is much more controlled but the quality is lower
180Zirconia has several transition phases. The belonging phases are ...
- Amonoclinic phase
- Btetragonal phase
- CCubic phase
- Dtrigonal phase
- Eorthorhombic phase
181There are different types of Hydrothermal Synthesis. These types are called:
- ASubcritical Synthesis
- BSupercritical Synthesis
- CHeterogeneous Synthesis
- DPrecipitation
- EModified Processes
182Colloidal Processing...
- AAllows the design of complex structures
- BCan mix methods: tape casting + dipping + piling
- CCan not be used for tailoring ceramics
- DNever depends on time
- EAll answers are false
183Tailoring ceramics through colloidal processing...
- APrecise control of the processing variables
- BCan generate microstructures with improved properties
- CTher resulting structures are always multilayers
- DIt only works for coatings
- EAll answers are correct
184Which of these sentences are correct when we are talking about the isoelectric point?
- AIt is a pH
- BIt happens when [a]+=[a]-
- CThe molecule carries no electrical charge
- DThe particle in water carries the same charge on all its surface
- EThe particle in water carries positive charge
185Which are the main design possibilities to tailor composite structures?
- ADispersions
- BCoatings
- CGradients
- DMultilayers
- ENone of them
186What is a supercritical fluid?
- AA supercritical fluid is any substance at a temperature and pressure above its critical point, where the limit between liquid and gas phases does not exist.
- BA supercritical fluid is a low density fluid
- CA supercritical fluid is a super magnetic fluid
- DThis material does not exist
- EThis fluid is always a gas
187Which of the following sentences are correct?
- ANanocrystals are structures with well-characterisez crystalline cores
- BNanoparticles are amorphous or inherently multidomain inorganic cores
- CNanoparticles are structures with well-characterisez crystalline cores
- DNanocrystals are amorphous or inherently multidomain inorganic cores
- ENanoparticles are amorphous or inherently multidomain organic cores
- FNone of the others are correct
188A supercritical fluid is interesting to study because…
- AIt can effuse through solids like a gas and dissolve materials like a liquid.
- BIt is any substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist.
- CThere is distinction between liquid and gas phases.
- DIt cannot effuse through solids like a gas.
- EIt cannot dissolve materials like a liquid.
189A supercritical fluid is interesting to study because…
- AIt can effuse through solids like a gas and dissolve materials like a liquid.
- BIt is any substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist.
- CThere is distinction between liquid and gas phases.
- DIt cannot effuse through solids like a gas.
- EIt cannot dissolve materials like a liquid.
190What of the following sentences about nanocrystals (NCs) are true?
- ANanocrystals are mono-dispersed nanometer size crystals.
- BNanocrystals are structures with well‐characterized crystalline cores.
- CNCs must be uniform in size and shape.
- DNCs must have well-formed crystalline cores and controlled surface chemistry.
- ENanocrystals are amorphous or inherently multidomain inorganic cores.
191Some steps of the ceramic processing are...
- AShaping
- BDrying
- CPressing
- DSintering
- EMelting
- FCasting
192Which of the following information could be usefull when designing a synthesis process?
- APourbaix diagrams
- BPhase diagram of the solvent: Pressure vs Temperature at constant Volume
- CXRD analysis
- DValues of the acidity and basicity constant
- EEllingham diagram
- FTernary phase diagram of H20 with the solvent
193Hydrothermal synthesis...
- AIs a heterogeneous reaction used for obtaining nanosized polycrcystals, among others, at low temperature comparing with solid state reactions
- BSupercritical conditions are when the reaction takes place over 100ºC and at 0.1MPa
- CSubcritical conditions reaches the end of the synthesis in a long time
- DSupercritical conditions reaches the end of the synthesis in a short time (h, days)
- ESubcritical conditions results in open structures with high control of the process.
194Which of the following are ceramic processing stages?
- AHomogenization
- BShaping
- CDrying
- DSintering
- ERecalculating
195Yttria-stabilized zirconia (YSZ) is a ceramic in which the crystal structure of Zirconia cubic phase is made stable at room temperature by addition of yttrium oxide. This ceramic can be synthesized by means of colloidal dispersion. In that process Urea has some roles. So, which of the next statements regarding the role of Urea are true?
- AHigh amount of Urea promotes sponge structure.
- BUrea is a dispersing agent.
- CUrea decreases the requiered amount of yttrium to keep cubic phase zirconia at room temperature
- DUrea is an agglomerating agent, promoting the sponge structure.
- EUrea is not used to manufacture cubic phase zirconia. Urea promotes the precipitation of tetragonal phase zierconia at 1000ºC in form of nanoparticles.
196About characteristics of Rheology:
- AHigh repulsion.
- BIntimate dispersion of phases.
- CHigher solid content, better green desinties.
- DHigher solid content, faster and better dry.
- ENone of the above.
197Processing from slurries
- AFiltration can be slip casting.
- BGelling can be a thermally gelled casting.
- CFiltration can be a tape casting.
- DDeposition evaporation can be a vaccum casting.
- EGelling can not be a chemically gelled casting.
198Which of the next statements are true?
- ASlurries behave as Non-Newtonian fluids. It means that dynamic viscosity is not constant.
- BSilly Putty can be characterized as a dilatant fluid, i.e, dynamic viscosity increases as stress is applied.
- CControlling the surface properties of a particle, we are able to control the behavior of that particle in a solvent media and obtain bulk materials with tailored properties.
- DPoise and mPa*s^(-1) are units of dynamic viscosity
- EAll the statements are false.
199When you put a particle inside a polar solvent....
- AIf the pH is lower than 7, diffuse layer is negatively charged
- BIf the pH is greater than 7, diffuse layer is positively charged.
- CIf the pH is greater than 7, stern layer is negatively charged
- DIf the pH is greater than 7, stern layer is positively charged.
- EThe charge of the diffuse layer does not depend on the pH of the solvent when it is polar.
200Which action/s increase the viscosity of a colloidal suspension?
- AIncrease the amount of solid particles
- BReduce the size of the solid particles
- CSet the pH near 7
- DIncrease the elestrosteric repulsion
- EPut a high or low pH
Informações
- Descrição
- Ingeniería Quiz sobre Renewable 2, criado por Ana Abella em 25-04-2017.
- Autor
- Ana Abella
- Idioma
- English
- Visualizações
- 18
- Etiquetas
- Avaliação
- Ainda sem avaliações Avalie este quiz