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问题 问答题

（5分）化学与人类生活密不可分。

（1）人们通过食物获取各种营养。

①水果和蔬菜富含的营养素主要有水和      。

②为了防止骨质疏松，人体每天必须摄入足够量的       元素。

（2）下列厨房用品所使用的主要材料，属于有机合成材料的是       （填字母序号）。

（3）人类以化石燃料为主要能源。

①天然气燃烧的化学方程式为      。

②下列做法有利于减少空气污染的是      （填字母序号）。

A．充分利用太阳能

B．大力发展火力发电

C．合理使用化石燃料

D．为方便出行，大量使用私家车

答案

 （1）①维生素 ②钙  （2）C和D （3①CH4 + 2O2  点燃 CO2 +2 H2O ②AC

 

题目分析：（1）①水果和蔬菜富含的营养素主要有水和维生素；②为了防止骨质疏松，人体每天必须摄入足够量的钙元素；(2) 厨房用品所使用的主要材料，属于有机合成材料的是C.塑料餐具和 D.橡胶手套；（3）①天然气燃烧的化学方程式为CH4 + 2O2  点燃 CO2 +2 H2O；②充分利用太阳能和合理使用化石燃料，有利于减少空气污染。

单项选择题

有关窗宽的论述，错误的是（）

A.窗宽决定显示CT值范围的大小

B.窗宽加大，提高图像中低密度组织对比

C.组织的CT值大于窗宽规定范围时呈白色

D.窗宽加大，显示图像原灰阶层次增多

E.调节窗宽可改变图像的密度差
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填空题


Motivation is "the driving force within individuals that impels them to action." And goals are the sought-after results (1) motivated behavior.
Motivation can be either positive or negative (2) direction. We may feel a driving force toward some object or condition, (3) a driving force away from some object or condition. For example, a person may be impelled toward a restaurant to fulfill a need, hunger, and away (4) an airplane to fulfill a need of safety. Some psychologists refer to positive drives (5) needs, wants or desires, (6) negative drives as fears or aversions (7) , though negative and positive motivational forces seem to differ dramatically (8) terms of physical and sometimes emotional activity, they are basically similar in (9) they both serve to initiate and sustain human behavior. (10) this reason, researchers often refer (11) both kinds of drives or motives as needs, wants and desires.
Goals, (12) , can be either positive or negative. A positive goal is one toward (13) behavior is directed and it is often referred to as an approach object. A negative goal is (14) from which behavior is directed away and it is sometimes referred to as an avoidance object. Since both approach and avoidance goals can be considered objectives of motivated behavior, most researchers refer to (15) types simply as goals. Consider this example. A middle-aged woman may wish to remain (16) attractive as possible. Her positive goal is to appear desirable, and (17) she may use a perfume advertised to make her irresistible. A negative goal may be to prevent her skin (18) aging, and therefore she may buy and use face creams. (19) the former case, she uses perfume to help her achieve her positive goal -- attractiveness; in the (20) case, she uses face creams to help avoid a negative goal -- wrinkled skin.
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