名词解释题碳循环carbon cycle

题目
名词解释题
碳循环carbon cycle
相似考题

1.● Feasibility studies occur in which life cycle phase (s)?A ConceptualB Conceptual or DevelopmentC ExecutionD Preliminary planningE any life cycle phase

2.Theoretical perfect combustion in a diesel engine yields by-products of_____.A.aldehydes and carbon dioxideB.water vapor and carbon monoxideC.nitrogen and carbon monoxideD.water vapor and carbon dioxide

3.According to Harry Morrison, businesses .A．will benefit from cutting carbon emissionsB．should buy carbon allowances for shoppersC．are required to make up for their carbon emissionsD．have encouraged shoppers to take their custom elsewhere

4.If all other conditions such as bore, stroke, speed, and mean effective pressures are equal, a two stroke/cycle diesel engine will develop approximatelyA.the same indicated horsepower as a four-stroke/cycle engineB.twice the indicated horsepower as a four-stroke/cycle engineC.one half the indicated horsepower as a four-stroke/cycle engineD.one power stroke for every two crankshaft revolutions

更多“碳循环carbon cycle”相关问题

  • 第1题：

    On Venus there is a lot of__________.

    A.water
    B.carbon dioxide
    C.carbon monoxide
    D.oxygen

    答案：B
    解析：
    由第二段的最后一句话中的“there is only a tiny amount of water there(Venus)”得知，A选项错误。第三段结尾说明，藻类通过火箭运往金星，然后“In a fairly short time，the algae will break down thecarbon dioxide into oxygen and carbon”，说明金星上有大量的二氧化碳。C和D选项错误。故选B。

  • 第2题：

    CYCLE81，CYCLE82，CYCLE83指令均为钻孔循环指令（SIEMENS系统）。


    正确答案:正确

  • 第3题：

    One hertz is equal to one ( )

    • A、cycle per centimeter
    • B、cycle per meter
    • C、cycle per second
    • D、cycle per eV

    正确答案:C

  • 第4题：

    关于CYCLE93指令，（）（SIEMENS系统）。

    • A、CYCLE93是切槽循环指令
    • B、使用CYCLE93指令可以简化编程
    • C、CYCLE93指令可实现断屑加工
    • D、CYCLE93指令可用于切削圆锥面和圆弧面
    • E、CYCLE93可用于径向沟槽的切削加工

    正确答案:A,B,C,E

  • 第5题：

    关于CYCLE83指令，下面说法正确的是（）

    • A、CYCLE83是深钻孔循环指令
    • B、使用CYCLE83指令可以简化编程
    • C、CYCLE83指令执行连续切削进给到孔的地步
    • D、完成CYCLE83指令后刀具将返回到参考平面
    • E、用CYCLE83指令钻孔切削到孔底后，刀具快速返回

    正确答案:A,B,D,E

  • 第6题：

    碳循环carbon cycle


    正确答案: 碳在大气、陆地生命体和土壤有机质等几个分室中的迁移和转化过程。

  • 第7题：

    阐述碳循环的基本路线，并解释人类活动如何对碳循环造成干扰？


    正确答案: 碳循环的基本路线是从大气储存库经过光合作用被植物吸收固定，一部分转移到动物体内，再从动植物通向分解者，最后又回到大气中去。
    岩石圈和化石燃料是地球上两个最大的碳储存库。此外水圈、大气圈、植被等也都是碳的储存库。每年碳的吸收与释放之间是平衡的，从而保证了大气中流通的碳保持在一定的数量之内。但由于人类每年大量燃烧化石燃料，从储存库中向大气中释放二氧化碳。同时森林的破坏又减弱了植被固定大气二氧化碳的能力，使越来越多的碳参与流通，导致大气中二氧化碳浓度增高，带来全球性气候变化。

  • 第8题：

    单选题
    The size of the exhaust valve opening is （）
    A

    most critical in a four-stroke cycle diesel engine

    B

    most critical in a two-stroke/cycle diesel engine

    C

    most critical in a four-stroke/cycle diesel engine if it is turbocharged

    D

    of equal importance in a two-stroke/cycle diesel engine as in a four-stroke/cycle diesel engine


    正确答案： A
    解析： 暂无解析

  • 第9题：

    单选题
    In diesel engines, the four basic events (intake, compression, power and exhaust) are performed once in （）.
    A

    two crankshaft revolutions in a two-stroke/cycle engine

    B

    two power strokes in a two-stroke/cycle engine

    C

    one power stroke in a two-stroke/cycle engine

    D

    two piston strokes in a two-stroke/cycle engine


    正确答案： B
    解析： 暂无解析

  • 第10题：

    单选题
    If all other conditions such as bore, stroke, speed, and mean effective pressures are equal, a two-stroke/cycle diesel engine will develop approximately（）
    A

    the same indicated horsepower as a four-stroke/cycle engine

    B

    twice the indicated horsepower as a four-stroke/cycle engine

    C

    one half indicated horsepower as a four-stroke/cycle engine

    D

    one power stroke for every two crankshaft revolutions


    正确答案： D
    解析： 暂无解析

  • 第11题：

    单选题
    The combustion of larger molecules,（）have multiple carbon-carbon bonds involves a more complex series of reactions.
    A

    what

    B

    which

    C

    that

    D

    who


    正确答案： D
    解析： 暂无解析

  • 第12题：

    判断题
    Natural systems can reduce the amount of carbon dioxide in the atmosphere caused by carbon emissions.
    A

    对

    B

    错


    正确答案： 对
    解析：
    录音中指出随着碳排放量的增加，空气中二氧化碳的含量从1750年以来已经增加了31%，自然通常可以把大部分碳排放吸收到海洋和森林中去，从而减少空气中碳的积累，因此题干正确。
    【录音原文】
    As a result of the steady rise in carbon emissions, the amount of carbon dioxide in the atmosphere has increased by 31% since l750—a rate unprecedented in the past 20, 000 years. Nature usually absorbs a large portion of these emissions in oceans and forests, known as “carbon sinks”, thereby slowing the rate of accumulation in the atmosphere. However, recent trends suggest that carbon emissions are outpacing absorption.

  • 第13题：

    共用题干
    第一篇

    Carbon Footprint

    How often do you travel by plane?How much electricity do you use?
    These days everyone is worried about the size of their carbon footprint.In order to reduce global warming we need to make our carbon footprints smaller. But how much CO2 are we responsible for?
    A new book might be able to help.The Carbon Footprint of Everything looks at the different things we do and buy,and calculates the amount of CO2 all of the following created:the ingredients, the electricity used in the brewery，the equipment,the travel and commuting of the beer,and the packaging. It's amazing how many different things need to be included in each calculation.And it's frightening how much carbon dioxide everything produces.
    But all of this can help us decide which beer to drink.From Berners-Lee's calculations,it's clear that a pint(568ml)of locally-brewed beer has a smaller carbon footprint than a bottle of imported beer. This is because the imported beer has been transported from far away,and it uses more packaging. The local beer only produces 300g of CO2,but the imported beer produces 900g! So, one pint of local beer is better for the environment than three cans of cheap foreign lager from the supermarket.
    Berners-Lee has even calculated the carbon footprint of cycling to work.Nothing is more environmentally-friendly than riding a bike,surely?Well,it depends on what you've had to eat before. To ride a bike we need energy and for energy we need food.So if we eat a banana and then ride a kilometer and a half,our footprint is 65g of CO2.However,if we eat bacon before the bike ride,it's 200g. In fact,bananas are good in general because they don't need packaging,they can be transported by boat and they grow in natural sunlight.
    So,does this mean that cycling is bad for the environment?Absolutely not,for a start,if you cycle,you don't use your car,and the fewer cars on the road,the fewer traffic jams.And cars in traffic jams produce three times more CO2 than cars traveling at speed.Cycling also makes you healthy and less likely to go to a hospital. And hospitals have very big carbon footprints!
    So maybe it's time for us all to start making some changes.Pass me a banana and a pint of local beer,please.

    To make our carbon footprints smaller,we should often________.
    A:cycle to work
    B:drink more local beer
    C:calculate the amount of CO2
    D:buy cheap things from the supermarkets

    答案：A
    解析：
    细节题。根据原文可知以下产生的二氧化碳量分别是：A选项，一品脱当地酿造的啤酒为300克，B选项，一品脱进口啤酒为900克，C选项，骑车前吃的香蕉为65克， D选项，骑车前吃的培根肉是200克。
    词义推断题。第三段第二句：原料、xxx所用的电量、设备、啤酒的运输和包装。由此可知A最合理，B’选项与原文的“设备”重复了，D选项同理，C选项与包装重复了。
    推断题。从第六段可以看出骑车是环保的，产生的碳足迹是少的，其他选项都没有在原文中体现这个意思。
    推断题。第五段最后一句：香蕉总体来说是很好的，因为它们无需包装，可以使用船只运输，并且在自然光照下生长。这些都是说香蕉产生的碳足迹少，并没有提到它是健康食品。A、B、D原文均有体现。
    主旨题。本文大意是阐述了我们的碳足迹量有多少。A、B和C均只是原文中的一点。

  • 第14题：

    简述碳循环的途径。


    正确答案: 碳循环的途径有三个：
    （1）途径之一是陆地生物与大气之间的碳素交换。
    ①细胞水平的
    ②个体水平的
    ③群体水平的
    ④食物链（系统）水平的循环
    （2）途径之二是海洋生物与大气之间碳素交换。
    （3）途径之三是化石燃料燃烧参与的碳循环。

  • 第15题：

    下列指令中，（）是毛坯切削循环指令（SIE州田NS系统）。

    • A、CYCLE93
    • B、CYCLE95
    • C、CYCLE96
    • D、CYCLE97

    正确答案:B

  • 第16题：

    关于CYCLE81指令，下面说法正确的是（）（SIEMENS系统）。

    • A、CYCLE81是深孔钻循环指令
    • B、使用CYCLE81指令可以简化编程
    • C、CYCLE81指令执行间歇切削进给到孔的底部
    • D、完成CYCLE81指令后刀具将返回到返回平面
    • E、用CYCLE81指令钻孔切削到孔底后，刀具快速返回

    正确答案:B,D,E

  • 第17题：

    钻镗循环的深孔加工时需采用间歇进给的方法，每次提刀退回安全平面的应是（）。（SIEMENS系统）

    • A、CYCLE81
    • B、CYCLE82
    • C、CYCLE83
    • D、CYCLE84

    正确答案:C

  • 第18题：

    论述森林生态系统的碳循环过程以及如何评价森林生态系统在全球碳循环中的作用？


    正确答案: 森林生态系统的碳循环过程：
    森林植物通过光合作用从大气吸收CO2，合成有机物质，一部分存贮在植物体内，其中一部分被消费者取食在食物链中进行传递，植物与动物体内的碳最后通过微生物的分解重新释放到大气中；植物在进行光合作用吸收CO2的同时，也通过呼吸作用向大气释放CO2。
    一个具体的森林生态系统是一个碳源还是一个碳汇，主要是比较森林生态系统的碳的总的吸收速率和总释放速率，吸收速率如果大于释放速率，该森林为碳汇，如果相反，则是碳源。总吸收速率与总释放速率的差为可用净光合速率与森林土壤的呼吸速率之差，可用这一差值来评价森林生态系统调节大气的作用。

  • 第19题：

    下面指令中，（）是切槽循环指令（SIEMENS系统）。

    • A、CYCLE93
    • B、CYCLE95
    • C、CYCLE96
    • D、CYCLE97

    正确答案:A

  • 第20题：

    单选题
    Proper lubrication of the main bearing is more easily obtained in a single acting four-stroke/cycle diesel engine than in a single acting two-stroke/cycle diesel engine because （）
    A

    bearing pressure in a four-stroke/cycle acting single diesel engine is continually reversed

    B

    bearing pressure in a two-stroke/cycle single acting diesel engine is continually reversed

    C

    the maximum bearing pressure is higher in a single acting two-stroke/cycle diesel engine

    D

    two-stoke/cycle diesel engines require more complicated lubrication piping


    正确答案： B
    解析： 暂无解析

  • 第21题：

    单选题
    Which of the following statements is true regarding the installation of piston rings on two-stroke/cycle, diesel engines as compared to four-stroke/cycle, diesel engines?（）
    A

    In a two-stroke/cycle engine, the rings run hotter, requiring the end gap to be greater

    B

    Some provision must be made in a two-stroke/cycle engine to keep the rings from binding in the ports

    C

    No gap is required to exist between the ends of the ring when cold in a two-stroke/cycle engine, but a small gap is required in a four-stoke/cycle engine

    D

    The gaps should be staggered on either side of a piston in a two-stroke/cycle engine, while staggering is not necessary in a four-stroke/cycle engine


    正确答案： A
    解析： 暂无解析

  • 第22题：

    名词解释题
    碳循环carbon cycle

    正确答案： 碳在大气、陆地生命体和土壤有机质等几个分室中的迁移和转化过程。
    解析： 暂无解析

  • 第23题：

    单选题
    Theoretical perfect combustion in a diesel engine yields by-products of （）.
    A

    aldehydes and carbon dioxide

    B

    water vapor and carbon monoxide

    C

    nitrogen and carbon monoxide

    D

    water vapor and carbon dioxide


    正确答案： C
    解析： 暂无解析

  • 第24题：

    单选题
    Why should you wear a self-contained breathing apparatus before entering the engine room after the fixed CO2 system has been discharged to combat a major fire?（）
    A

    Because carbon dioxide dilutes the oxygen concentration in the atmosphere and may cause asphyxiation

    B

    Because carbon dioxide breaks down in a fire into carbon monoxide which may cause blood poisoning in the person breathing this gas

    C

    Because carbon dioxide is a colorless and odorless gas that becomes highly toxic in the presence of high temperatures and will quickly incapacitate a person exposed to this gas

    D

    This action is unnecessary as carbon dioxide is not poisonous nor toxic but is a relatively harmless gas


    正确答案： C
    解析： 暂无解析

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