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工学
单选题结构单元相同的高分子链，其结晶能力最高的异构体为______。
单选题Which is not the advantage of Carbon/Carbon composites? A) Stronger at high temperatures than at low temperature. B) Easy oxidation at high temperature C) High specific strength D) Good resistance to thermal shock.
单选题现有下列铸铁，请按用途选材。A．HT250B．KTH350-10C．QT600-2
单选题陶瓷一般是不导电的绝缘体，其原因是( )。 A．原子排列不规则 B．原子排列不致密，空隙多 C．原子结合键是离子键或共价键
单选题由Clausius-Clapeyron方程可知，随着压力的增加，γ-Fe转变成α-Fe的温度______。
单选题在非化学计量化合物ZrO2-x中存在的晶格缺陷是______。 a．阴离子空位b．阳离子空位c．阴离子填隙 d．阳离子填隙
单选题Alow molecular weight polymer additive that enhances flexibility and reduces stiffness and brittleness is referred as ______ A．Colorants B．Plasticizer C．Flame retardants D．Foam agents
单选题The results obtained from torsion test can be plotted as a ______ diagram. A) σ-ε B) s-N C) τ-γ D) T-θ
单选题What main advantage do cellular plastics offer? A．Reduced density B．Improved crystallinity C．Greater density D．Improved strength
单选题离子晶体通常借助表面离子的极化变形和重排来降低其表面能，对于下列离子晶体的表面能，最小的是______。
单选题退火孪晶出现的几率与晶体的层错能的关系为______。
单选题Which advantage do smart polymeric materials offer designers? A．Eliminate selection problem, B．Reduce raw materials costs C．Adapt to environmental change D．Reduce processing
单选题金属Mg的滑移系为______。
单选题冷变形金属的回复温度______再结晶温度。
单选题Which of the following describes is correct as for carbon and graphite fibers? A．Carbon fiber has a higher modulus than graphite fiber B．Graphite fiber has a lower content than carbon fiber C．Carbon fiber has a higher pyrolyzinig temperature than graphite fiber D．None of above.
单选题非均匀形核所需的过冷度是合金结晶温度Tm的______倍。
单选题在置换型固溶体(substitional solid solution)中，原子扩散的方式一般为______。
单选题The following statement ofinert gases is right except______ A) Inert gases are also called noble gases B) Inert gases are mostlyinactive C) Inert gases do not get involved in making compounds with other elements D) Inert gases have their outer energy levels incompletely full ofvalence electrons
单选题Inert gases can also be called ______. A) Noble gases B) Active C) Group 5 elements D) Stable
单选题Which statement of elastic modulus is NOT correct? A) Elastic modulus is also known as Youngs modulus B) The higher the magnitude ofelastic modulus the weaker the interatomic bonding forces C) Elastic modulus is the constant ofproportionality in Hookes law D) Elastic modulus can be measured graphically in the elastic region ofthe stress-strain diagram