氧化（oxidation）
氧化（oxidation）
相关考题：
下列说法中正确的是( )。A、氧化剂得到电子，氧化数降低，具有氧化性B、氧化剂得到电子，氧化数降低，具有还原性C、氧化剂失去电子，氧化数升高，具有氧化性D、氧化剂失去电子，氧化数升高，具有还原性E、氧化剂得到电子，氧化数升高，具有氧化性
A diesel engine exposed to widely varying ambient temperatures should use to a lubricating oil with .A.a high viscosity indexB.a low viscosity indexC.neutralize acidsD.resist oxidation at high temperatures
正确的说法是A、氧化剂得到电子，氧化数降低，具有氧化性B、氧化剂失去电子，氧化数升高，具有氧化性C、氧化剂得到电子，氧化数降低，具有还原性D、氧化剂失去电子，氧化数升高，具有还原性E、氧化剂得到电子，氧化数升高，具有氧化性
Is it the different types of tea plants that determine the colour and aroma of tea? The answer is no.Actually, it is the processing of tea that finally decides the tea types.For example, black tea requires 100% oxidation and green tea requires almost no oxidation.So tea processing is quite an important factor in the production of tea.Anyway, the normal processing of tea includes the following four basic steps:1.New leaves are spread in order to reduce water content until they are pliable enough to be rolled.This process is called withering.2.The second step is rolling the withered leaves.Oils and extra moisture are released.This process can be done with machinery or by hand.3.The third step is called oxidation or fermentation.In this process the leaves turn from green to bright copper in colour.This step decides what type of tea we want.4.The last step is drying the leaves to stop the oxidation process.The leaves should be dried thoroughly without burning.Decide each statement is T (true) or F (false) based on Passage B.6.The processing of tea decides the tea types.7.Green tea requires a little oxidation.8.Withering makes the tea leaves release oils and water.9.Rolling the withered leaves can be done only with machinery.10.Burning the leaves is the last step of tea processing.
Oil oxidation as a result of excessively high lube oil temperature, is harmful to a diesel engine BecauseA.oil foaming will always occurB.large quantities of oil are consumedC.lube oil viscosity is always decreasedD.corrosive by-products are usually formed
Sludge may be formed in the oil in the crankcase of a reciprocating air conditioning compressor as a result of ______.A.refrigerant bubbles in the lube oilB.refrigerant reducing the lube oil viscosityC.oxidation(氧化) of the lube oil from overheatingD.reducing the floc or cloud point of the oil
Which statement about inert gas pressures in a cargo tank is TRUE ________．A.The pressures of the inert gas in the tank may create excessive pressure at the pump while dischargingB.Gas pressures should be maintained at the highest permissible level throughout the discharging processC.High gas pressures may cause pyrophoric oxidation in the tankD.High gas pressures may cause loss of suction when stripping
What can cause a lack of oxygen in a chain locker ________．A.AbsorptionB.OsmosisC.EvaporationD.Oxidation
The oil components including polar compounds formed as a result of oxidation of some oil fractions in the marine environment dissolving in seawater defines ______．A.Oxidation and destructionB.DissolutionC.Oxidation and destructionD.Sedimentation
The process that oil spilled in sea is adsorbed on the suspended material and deposited to the bottom defines ______．A.Oxidation and destructionB.DissolutionC.Oxidation and destructionD.Sedimentation
______is not a process of weathering of the oil spilled in the sea water.A.BiodegradationB.DissolutionC.Cleaning up by crew with skimmersD.Oxidation including photooxidation
______is not a process of weathering of the oil spilled in the sea water.A.EmulsificationB.Sedimentation / SinkingC.Oxidation including photooxidationD.Burning organized by RCC
资料：What，if anything，do we gain by clinging to our antioxidant supplements？Very little，according to an accumulating body of research. We don’t need massive doses of antioxidants，we need stress to compel our own bodies to create antioxidants.“Everybody thinks oxidation is bad，and that antioxidants are good，”says Dr.Jones，“That’s bogus. A little bit of poison is good.”That poison can actually come from plants，especially those that have survived harsh conditions. Foods that have survived harsh conditions make us stronger by stressing our bodies，not because they’re rich in antioxidants.As the science quarterly Nautilus explains，plants have developed an arsenal of chemicals to help them ward off insects and grazers. These“antifeedants，”when ingested by humans，trigger the body to release proteins and activate genes that “produce antioxidants，enzymes to metabolize toxins，proteins to flush out heavy metals，and factors that enhance tumor suppression.”Plants prepare your body to handle toxins in the same way as exercise prepares you to race-by stressing your body. And supplements，says Dr.Hooper，interrupt this process.“These antioxidant supplements are like a Trojan horse，”continues Dr.Hooper. They say，I’m a good guy. You guys go to sleep and while the defense is asleep the antioxidants get rid of any oxidation. It puts the defense-system’s army to sleep.While Dr.Jones acknowledges the benefits of vitamin E for muscle cramps and macular degeneration，he doesn’t approve the idea that it improves one’s physical performance. He suggests that athletes in intense contact sports such as soccer and football benefit from trauma. “Players have to be hit with pads on Tuesdays and Thursdays in order to compete on Sundays-they need that actual trauma.”he says.“Everything in our society is geared toward，How can we reduce stress？”adds Dr.Hooper. “When it should be just the opposite. We need stress. Stress is good.Which of the following statements is true according to the article？A.A large amount of antioxidant supplements are not necessary.B.Oxidation can not do anything good at all to our body.C.Plants surviving hard conditions can produce a lot of antioxidant.D.Antioxidant supplements can improve one’s physical performance.
Point out the coordination number and the oxidation number of the central atom in coordination compound [Co(H2NCH2CH2NH2)2(NO2)Cl]Cl（）A、4，ⅡB、6，ⅡC、6，ⅢD、4，Ⅲ
红酒变质的原因是什么？A、酒已经氧化了（Oxidation）B、酒里面有硫化物（Sulphide）和硫醇（Mercaptans）C、酒里面有挥发性酸（VolatileAcid/Volatility）
单选题The oxidation by-products forming in diesel engine lube oil can cause （）ApittingBsludgeChard varnishDall of the above
单选题The Total Base Number (TBN) value of diesel engine lube oil refers to its ability to （）Aresist changes in viscosity with changes in temperatureBresist emulsificationCneutralize acidsDresist oxidation at high temperatures
单选题After stopping oily water separator, sea water should be permitted for （） minutes,（）should be closed after stopping pump to reduce oxidation corrosion of inner wall.A15；inlet valueB15；inlet and outlet valueC30；inlet valueD30；inlet and outlet value
单选题Water allowed to accumulate in the hydraulic system oil will cause an oxidation process producing by- products which are normally （）.Agums, acids, and varnishesBremoved by cellulose type filtersCneutralized by oil additivesDnot removed by absorbent filters
单选题Oil oxidation, as a result of excessively high lube oil temperature, is harmful to a diesel engine because （）Aoil foaming will occurBlarge quantities of oil are consumedClube oil viscosity is always decreasedDcorrosive by-products are usually formed
名词解释题oxidation-reduction potentials, redox potentials (氧还电位)