实践教程客观题(毛概)搜题用什么软件最好
klason, mwl, cel等都是()。
下列哪个木质素制备物可用于结构分析:
阔叶材的木质素先体有:
松柏醇有()个甲氧基。
松柏醇在酶(过氧化物酶、漆酶)作用下脱氢生成()种稳定的苯氧共振游离基。
偶合是任意的,但几率不一样,主要取决于:
使木质素大分子溶解除去的途径有:
木质素苯氧基的紫外吸收峰在()附近。
木质素红外光谱中在1500 cm-1,1600 cm-1,1430 cm-1处的振动属于()振动。
由g、s和h结构单元构成的木质素是()。
木质素的特征官能团是()。
下列原料中,()的甲氧基含量最高。
下列原料中,()的甲氧基含量最低。
禾本科木质素的对-香豆酸和阿魏酸多数以()的形式与其它苯丙烷单元相连。
4-o-氧游离基聚合的几率:
木质素通过()连接而成的,具有三度空间网状结构的芳香族的高聚物。
木质素在植物体内的作用有:
木质素分离困难的原因有:
木质素只存在于细胞壁的微纤丝之间。
木质素只存在于胞间层。
磨木木质素、纤维素酶解木质素,二氧六环木质素和硫酸盐木质素的分离原理相同。
木质素大分子的合成主要是游离基偶合。
碱性条件下,a-o-4键断裂。
针叶材木质素的醚化程度比阔叶材高。
木质素的酚羟基大多游离,少数醚化。
木质素和()一起,填充在细胞壁的微纤丝之间。
以天然状态存在于植物体中的木质素叫()。
木质素的分离方法之一是溶出(),保留木质素。
对香豆醇有()个甲氧基。
木质素先体合成路径中,合成和络氨酸的路径叫()路径。
木质素大分子的合成主要以()聚合的方式进行。
分离木质素的分子量随分离条件不同而异,具有()性。
()木质素的对-香豆酸和阿魏酸多数以酯的形式与其它苯丙烷单元相连。
碱性介质中,木质素形成的()中间体是亲核反应的中心。
酸性介质中,木质素形成的()中间体是亲核反应的中心
木质素分离通常遵循哪些原则?
木质素的先体主要有哪几种?写出结构式。
说明为什么阔叶材木质素的beta-o-4连接键型要多于针叶材木质素。
比较下列各组名词: (1)综纤维素和半纤维素 (2)纤维素和alfa-纤维素 (3)klason木质素与总木质素
试描述植物纤维主要化学成分在细胞壁各层中的含量及分布状况。
根据硫酸盐法和烧碱法蒸煮亲核试剂亲核能力的大小,分析两种蒸煮脱木质素的异同点。写出主要反应式。
比较酸性亚硫酸盐蒸煮与硫酸盐蒸煮脱木质素反应的特点,并分析酸性亚硫酸盐蒸煮溶出木质素(木质素磺酸盐)与硫酸盐蒸煮溶出木质素(硫酸盐木质素)的性质差异。
纤维素的基本结构单元是()。
纤维素基的分子式为()。
纤维素分子是()分子。
纤维素大分子的连接方式为()。
纤维素形成分子间氢键的原子是:
纤维素分子层与层之间的结合力是:
热力学上,下列哪种纤维素结晶变体更稳定?
自然界中的纤维素大都是下列哪种晶体类型?
吸湿的本质是:
干纤维吸湿的描述,哪个是错的?
以下哪个不是结晶区间润胀剂?
纤维素在热碱液中的反应不包括:
纤维素在100 oc碱液中的反应有:
剥皮反应的过程包括以下4步,排序正确的是: a 、醛糖-酮糖互变,形成果糖; b 、重排,脱落的糖基重排成葡萄糖异变糖酸溶于碱液; c 、beta-分裂,产生新的还原性端基继续剥皮反应; d 、还原性端基转变成开链式醛糖;
温度对纤维素的润胀和水解起的作用是:
纤维素结晶区的特征有:
形成氢键的条件有:
以下哪个是结晶区间润胀剂?
纤维素葡萄糖基环上的反应有:
水解纤维素与纤维素的比较,性质有:
开链式葡萄糖是l糖。
纤维素中间糖基有2个伯醇羟基和1个仲醇羟基。
纤维素分子的所有的氢(h)都在直立键上(a键)上,而所有的羟基(-oh)都在平伏键(e键)上。
纤维素具有两相结构。
纤维素结晶区与无定形区是截然分开的。
同一相对湿度下,解吸时的湿含量总是低于吸附时的湿含量。
溶解时超分子结构并不一定完全被破坏。
结晶区间的润胀可以分为有限润胀和无限润胀。
纤维素在naoh溶液中的润胀,随碱浓度的增加而增加。
纤维素剥皮反应就是非还原性端基逐个脱落。
剥皮反应对纤维素的dp有影响。
纤维素在碱性介质中,易生成以以酸性型氧化纤维素为主的氧化产物。
纤维素是beta-d-吡喃型葡萄糖基通过()连接而成的线型高分子化合物。
纤维素分子所含有葡萄糖基的数目称为()。
纤维素非还原性端基有()个仲醇羟基。
纤维素非还原性端基有()个伯醇羟基。
纤维素还原性端基有1个伯醇羟基,2个仲醇羟基和1个()羟基。
纤维素大分子排列而成的聚集体的结构称为其()结构。
纤维素由结晶区和()区交替排列而成。
纤维素纤维吸收( )液体后,体积增大,内聚力下降,纤维变软,但仍保持外观形态。
高分子物质溶解就是指以( )状态进入溶液。
温度对润胀的影响:高温( )于纤维素纤维的润胀。
纤维素在中性介质中,易生成( )型氧化纤维素为主的氧化产物。
比较150℃下纤维素碱性水解与酸性水解反应及其对纤维素结构的影响。
简述木材中的主要半纤维素及其结构特点
磨削加工时,常在轴的根部和孔的底部做出环形沟槽,以保证加工到位及装配时零件靠紧,这种环形沟槽称为( )。
盘盖类零件表达方案的选择,主视图轴线应( )放置。
车削时常在轴的根部和孔的底部做出环形沟槽,以保证加工到位及装配时零件靠紧,这种环形沟槽称为( )。
选择箱体类零件的表达方案时,主视图应该按零件的( )放置
选择回转类零件的表达方案时,主视图应该按零件的( )放置。
当轴上有多个键槽时,键槽的方向分布在轴的( )。
如图为套筒零件图,零件上有一处退刀槽采用了( )表达方法。
1.零件图包括( )、( )、技术要求、标题栏四项内容。
倒角一般加工在( )和( )。
叉架类零件一般分为( )部分、( )部分、( )部分。
选择零件主视图外的其它视图时,一般应( )。
该零件图图形表达采用了哪些表达方法?
分析该零件图图形表达采用了哪些表达方法。
铸造件上常见的合理结构有哪些?
零件图上的技术要求一般都注写在标题栏附近。
为减少零件加工面积,提高接触精度,往往在零件相应的位置上做出凸台和凹槽。
盘盖类零件表达方案的选择,除了主视图外,往往还需增加圆视图。
如果箱体类或叉架类零件的工作位置倾斜,在选择表达方案时,主视图应将零件放正。
钻孔时,孔的轴线应垂直零件的加工表面。
表达实心轴类零件上的孔、槽结构,可以选用全剖视图。
箱体类或叉架类零件上的肋板结构,一般选择移出断面图或重合断面图表示。
铸造件的两表面相交处设计成圆角。
当轴上有多个键槽时,键槽的宽度应随轴径变化。
箱体类、叉架类零件主视图一般选择按加工位置放置;回转类零件主视图一般选择按工作位置放置。
读轴支座零件图,尺寸22,66是哪个孔的定位尺寸?
读图,零件的φ4孔深( )mm?
主要尺寸——配合尺寸、重要的结构尺寸、重要的安装尺寸——应该从( )基准出发直接标注
m6-7h的孔有( )个?
读零件图,回答问题: c3表示倒角为( )度? c2表示倒角锥台高度为( )?
读零件图,回答问题: 未标注圆角尺寸为( )? 2×m6-6h的定位尺寸为( )?
配合尺寸属于( )尺寸,应从( )基准出发标注
读轴支座零件图,孔2×φ10的定位尺寸为( )
零件的尺寸基准分为( )基准和( )基准
判断零件键槽的尺寸标注是否正确
判断轴上键槽的尺寸标注是否正确
判断锪孔的尺寸标注是否正确
两个零件的相关尺寸,其基准和标注方法应一致
主要尺寸应直接标注,非主要尺寸可按形体或加工工艺标注
判断零件退刀槽尺寸标注是否正确
判断零件的尺寸标注是否正确
评定表面粗糙度最常用的高度参数是( )
以下符号中,哪个是去除材料获得的表面?
表面粗糙度符号的尖端必须从( )指向材料表面
如图表面粗糙度代号中,ra3.2的含义为( )
下图中代号表示:ra3.2表示此表面采用( )方式获得?
图中要求最高的表面,表面粗糙度数值为ra( )?
读图,判断φ50h7外圆表面最终的表面粗糙度为多少
表面粗糙度代号可以标注在可见轮廓线、尺寸界线或它们的延长线上
零件上所标注的表面粗糙度代号,是该表面完工后的要求
同一张图样,一般一个表面只标注一次表面粗糙度代号
当零件所有表面具有相同的表面粗糙度要求时,必须逐一单个注出其表面粗糙度代号
图中标注的表面粗糙度代号,代表右图中立体1—6表面的表面粗糙度要求。
在满足功用的前提下,尽量选用较大的表面粗糙度参数值,以降低生产成本
在同一零件上,工作表面的粗糙度参数值应小于非工作表面的粗糙度参数值
一般来说,尺寸和表面形状要求精确程度高的表面,粗糙度参数值大
读图,φ12h7/f6是( )制的间隙配合
尺寸φ12g7中,g7表示( )
在配合尺寸φ50f8/h7中,关于尺寸φ50f8的说法哪种是正确的
尺寸φ30h7/n6中,φ30h7表示( )
读图,尺寸的下极限偏差为
图中哪个尺寸的极限偏差标注是正确的( )
读图,图中右图中孔的尺寸标注应为( )
读图,尺寸φ18的公差大小为( )
读图,如果在右图中标注轴的尺寸及公差带代号,应该是( )
极限偏差是( )减去基本尺寸所得的代数差
最大极限尺寸与基本尺寸的差值为( )
最大极限尺寸( )基本尺寸
允许尺寸变化的两个界限值称为( )
读图,图中φ50f8/h7属于基轴制配合
读图,尺寸50的公差值为0.024μm
读图,图中h7/f7属于间隙配合
读图,该尺寸的公差为-0.07
尺寸公差可为正值、负值或零
相互配合的孔和轴,其基本尺寸必须相等
讯问与审问、审讯的区别
讯问与询问的区别
讯问和盘问的区别
犯罪七要素?
all shakespeare’s works are written in ________.
which of the following is a tragedy written by shakespeare?
which character is not a noble hero with a tragic flaw in shakespeare’s tragedies?
the leading form of literature in the victorian era is ________.
the novel vanity fair is the masterpiece of the author ________.
________ is a representative of english critical reali in the 19th century.
of dickens’ novels, ________ is considered most autobiographical.
ode to the west wind is written by ________.
“beauty is truth, truth beauty.” is a famous quotation of ________.
in a historical sense, ________ was a movement in philosophy, political theory, and the arts that flourished in england from 1750 to 1850.
who introduced christianity into britain?
which of the following is not one of the three germanic tribes that came to be the basis of modern english race?
in the year 1066, william the conqueror invaded england and defeated the saxon king harold at ______.
it was not until the end of ______ that english language finally took the place of french in all classes of society in england.
______ was forced to sign the magna carta in june 1215 with the barons of medieval england.
the king who believed the “divine right” to govern, and who was condemned to death during the english civil war was ______.
according to marx, it was ______ that brought into power, along with william of orange, the landlord and capitalist appropriators.
it was during ______ when the english navy defeated the spanish armada.
the sparkle that set off world war i was the ______.
“blood, toil, tears and swear” was delivered by winston churchill during ______.
in england, what is a particularly suitable topic of conversation?
who once observed that 'when two englishmen meet, their first talk is of the weather'?
which of the following statements is not kate fox's research finding?
which rule of english weather-speak is not mentioned?
what is the correct response to 'how do you do'?
which word may not be used to describe the english leave-takings?
which word or expression may not be used to describe how the english feel if the long goodbye has been cut short?
which of the following statements is not true about english pub?
how can one let bar staff know that he is waiting to be served?
what is not the usual practice in english pubs?
the bbc is mainly financed by ______.
who had ever the only control of the airwaves in the uk except?
which of the following about the bbc is not true?
which of the following is a tabloid?
which of the following is not true about the times?
________ is reflected by critici toward television since its creation.
the “lowest common denominator”refers to ______.
newton n. minow said, “if each of the audience sit down in front of their television set for a day, until the station signs off, i can assure you that what you will observe is ____________.”
the full name of britain is ____________?
united kingdom is not a single country, but instead is a country of countries. it contains inside of it _______ co-equal and sovereign nations.
___________ is the most important river in scotland.
what are the official languages spoken in wales?
it is believed that the stonehenge was built there about 3,500 years ago by the ancient britons and was used for _________________.
________ is the capital of scotland.
the tower of london dates back to 1066, at the days of william the conqueror. over the years the tower has been used for different purposes, which of the following is not the correct usage of the tower?
historically, manchester as the birthplace of both the first true _______ and _________ used to transport goods during the industrial revolution.
northern ireland is a mostly rural, green land with low hills and is suitable largely for __________________.
what is the glasgow's top attraction?
which sport is bred in france, born in england, widely performed in the united states, and finally got prevalent worldwide?
________ was established in 1877, held from june to july each year on a lawn court.
which tournament is the fourth largest event in the world?
the phrase “on a sticky wicket” means ________.
which film of hitchcock was often cited as the first british sound feature film?
which of the following is not on the list of famous british film magazines?
who was the only “consulting criminal” of the series of sherlock?
in doctor who, which one is not on the list of numerous reoccurring enemies during the doctor’s travels?
the three olympic games were held in london in the year of ________ respectively.
britain is a parliamentary democracy with a ______.
which of the following is not correct?
among the main components of the british constitution, ______ are the most important and take precedence over others if there is a clash.
the two major parties in britain are ______ and ______.
how often does the general election in britain take place?
which of the following is the most important advantage enjoyed by the british first-past-the-post method?
the role of the ______ branch of government is to carry out the political system’s policies, laws or directives.
the executive power is in the hands of ______.
which of the following is not one of the functions of the house of commons?
in british society, what is the dominant principle that the queue is symbolic of?
what would the english do if someone has committed the sin of jumping a queue?
when the english moan about their work, which of the following aspects do they not moan about?
what is not the tone of their work-moaning?
what is it that most english people would not do when they are faced with unappetizing or even inedible food?
which of the following statements is not true about the word ‘typical’?
which of the following statements is not true about humour?
which of the following statements is not true?
what is the deeply ingrained rule?
by law, all children of compulsory school age (5 to 16) must receive a __________education that is suited to their age, ability, aptitude and special educational needs (sen).
the national curriculum consists of a set of core and foundation subjects. what are the core subjects?
which kind of school is government-funded schools which provide education free of charge to pupils?
which of the following statement is true?
in the united kingdom, they have different types of schools, like state school, independent and _________ school.
what is a “sandwich course” in the uk university programs?
which of the following statement is false?
if you want to apply for a good university at uk, you do need ________ grades to be considered for a place at a highly selective university.
the following statements are the tips for applicants of a highly selective university. make your judgment and tick out the false tip.
which of the following statements about the history of university of manchester is not true?
women in britain, having some qualifications, were enfranchised until ______.
mary wollstonecraft, as the first feminist philosopher, in her a vindication of the rights of woman in 1792, argued that _______.
suffragettes particularly refers to militants in the united kingdom such as members of the women's social and political union (wspu). the word “militant” probably means ______.
about queen elizabeth i, what can be inferred from the passage?
her name and history will consistently serve as a brutal yet remarkable reminder of britain's past. correct understanding of the sentence is ____________.
margaret thatcher, the iron lady, which of the following about her is not true?
which one of the following causes of british love for hats is not mentioned in the lecture?
the wedding of prince harry and meghan markle __________.
________ is george gordon byron's masterpiece, a great comic epic of the early 19th century, a poem based on a traditional spanish legend of a great lover and seducer of women.
_______, the british boasted that they had “an empire on which the sun never sets”.
which of the following statements is not true about “how are you”?
which of the following is the most famous of all british newspapers?
london’s landmarks are some of the most recognizable in the world. which of the following is not a landmark of london?
who was awarded a special gold cup by queen alexandra?
when the mps are elected, the leader of the party with the largest number of members returned to the house of commons becomes ______.
which of the following statements is not true about work moaning?
eton has educated 20 british prime ministers and many celebrities in the world. which of the following people hasn’t graduated from eton?
generally speaking, after shakespeare, the english drama was undergoing a process of prosperity.
it was not until the end of the wars of the roses that english language finally took the place of french in all classes of society in england.
when customers are waiting to be served, they should adopt an expectant, hopeful, even slightly anxious expression.
most of the uk's commercial radio stations generally broadcast present-day popular music.
the full name of britain is the united kingdom of great britain and northern scotland.
audrey hepburn made a name of herself for playing the lead role in my fair lady.
the king/queen in britain enjoys real power and she reigns and rules with the help of her ministers.
most english people, faced with unappetizing or even inedible food, tend to complain face-to-face to the waiter.
state schools are government-funded schools which provide education free of charge to pupils.
alfred tennyson, poet laureate of the united kingdom and one of the most popular english poets, sang highly of male supremacy and female subservience in the excerpt taken from the princess.
emily brontë and charlotte brontë are noted for their best-known novels wuthering heights and________, which are largely the love stories of a woman for a man.
“magna carta” means ______ and it remains a cornerstone of the british constitution.
according to the context rule, weather-speak can be used as a simple greeting, ________, and a filler.
the national daily newspaper in the u.k. can be ided into serious/quality papers and ________.
________is scotland’s capital.
the phrase “to throw a googly” means to ________.
britain is a parliamentary democracy with a constitutional monarchy in which the power of the monarch is limited by the ________.
humour is their “________”. they do not have to switch it on deliberately, and they cannot switch it off.
in the united kingdom, they have different types of schools, like state school, independent and ________ school.
the reign of queen elizabeth i is known as ________, a time that saw the emergence of england as a world power.
杆件的分类包括
恒载是长期作用于结构的不变荷载。常见的恒载有:
支座的简化形式有以下几种:
据荷载分布情况可分
结点的简化包括:
结构简化包括
杆件结构的特征是其( )要比长度小得多。
板壳结构(薄壁结构)的特征是其( )要比长度和宽度小得多。
( )结构的特征是长宽高尺寸相当。
选择计算简图的原则是: (1) 从实际出发――计算简图要反应( )的主要性能; (2) 分清主次,略去细节――计算简图要便于计算。
结构力学中材料性质的简化:对组成构件的材料一般假设为( )、均匀、各向同性、弹性。
据活载作用的性质分( )、动力荷载。
动力荷载是随( )或短暂时段内突然作用或消失的荷载使结构产生显著加速度,惯性力不能忽略。
活载可分为可动载和( )。
桁架的特点所有的杆都是直杆组成,杆两端均为理想的( )。
拱的特点是轴线为曲线,竖向荷载下拱脚处有( )。
静力荷载是不随( )或变化极为缓慢的荷载。
梁是受弯构件,主要承受( )的作用,轴线常为直线。
组合结构的特点粱式杆主要承受弯矩的作用,( )只承受轴力,由桁架和梁或刚架组合。
钢屋顶桁架,结点焊接。在结构简化时杆件以( )代替,且认为位于同一平面内并经过结点中心。
什么是结构?(10分)
结构力学的研究任务?(15分)
结构力学对于能力的培养包括哪些方面?(20分)
选择计算简图的原则是什么?(10分)
结构与基础之间的连接方式有哪几种?(15分)
杆件结构的分类有哪些?(15分)
荷载的分类有哪些?(15分)
2-4、2-7、2-9、2-11
作业1
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