关于阿尔茨海默病（AD）的病因学、发病机制，以下错误的是（） A.AD患者脑部乙酰胆

某实验小组在进行“用单摆测定重力加速度”的实验中,已知单摆摆动过程中的摆角小于5°;在测量单摆的周期时,从单摆运动到最低点开始计时且记数为1,到第n次经过最低点所用的时间内为t;在测量单摆的摆长时,先用毫米刻度尺测得悬挂后的摆线长(从悬点到摆球的最上端)为L,再用游标卡尺测得摆球的直径为d.

(1)用上述物理量的符号写出求重力加速度的一般表达式g =                   .

(2)实验结束后,某同学发现他测得的重力加速度的值总是偏大,其原因可能是下述原因中的           .

A．单摆的悬点未固定紧,振动中出现松动,使摆线增长了

B．把n次摆动的时间误记为(n + 1)次摆动的时间

C．以摆线长作为摆长来计算

D．以摆线长与摆球的直径之和作为摆长来计算(3) 某同学在做“用单摆测定重力加速度”的实验中，用秒表测单摆完成40次全振动的时间如图所示，则单摆的周期为______________s。

（4）为了提高实验精度，在实验中可改变几次摆长L并测出相应的周期T，从而得出一组对应的L与T的数据，再以L为横坐标、T²为纵坐标将所得数据连成直线，并求得该直线的斜率k。则重力加速度g=________ 。(用k表示)若根据所得数据连成的直线的延长线没过坐标原点，而是与纵轴的正半轴相交于一点，则实验过程中可能存在的失误是             ，因此失误，由图象求得的重力加速度的g             (偏大，偏小，无影响)

兴趣小组的同学在进行“探究蔬菜水果中维生素C含量”的实验。根据学过的知识，大家知道常吃水果蔬菜能预防坏血病，增强机体免疫力。因为新鲜水果蔬菜中含丰富的维生素C，但维生素C的性质不稳定，高温烹调或长时间储存会破坏维生素C。黄瓜作为常见的蔬菜，究竟生食还是熟食能使人体摄入更多的维生素C呢？

请你帮助他们完成下面的探究过程 。

（提示：紫色的高锰酸钾溶液与维生素C发生反应颜色会变浅退去）

(1)兴趣小组同学提出的问题是：____________？

(2)你作出的假设是：___________。

(3)制定的计划如下：

①．称取等量的两份黄瓜，将其中一份煮熟，分别榨汁液并倒入两个小烧杯中。

②．取2支洁净干燥的小试管编号1、2，分别注入不同浓度的高锰酸钾溶液2ml。

③．用滴管吸取生黄瓜汁液，逐滴滴入1号试管，边滴边振荡，直到高锰酸钾溶液褪色为止，记录所用汁液的滴数n 。

④．用同一滴管吸取熟黄瓜汁液，逐滴滴入2号试管，振荡并观察高锰酸钾溶液的颜色直到褪色为止，记录所用汁液的滴数m。

(4)讨论发现制定的计划中有不合理之处：

①．是________________。

②．是_____________________。

(5)按照修改完善的计划进行重复多次实验。实验现象表明：使2ml高锰酸钾溶液全部褪色滴加的熟黄瓜汁液的滴数m多于滴加的生黄瓜汁液的滴数n。

(6)据此你得出的结论是：_________维生素C的含量高，黄瓜_________________食更好。

长期贷款是指贷款期限在()的贷款。

A.3年以上(不含3年)

B.5年以上(不含5年)

C.3年以上(含3年)

D.5年以上(含5年)

A new research has uncovered that culture is a determining factor when people interpret facial emotions (情感)．The study reveals that in cultures where emotional control is the standard，such as Japan，the focus is placed on the eyes to interpret emotions. Whereas in cultures where emotion is openly expressed，such as the United States，the focus is on the mouth to interpret emotions.

“These findings go against the popular theory that the facial expressions of basic emotions can be universally recognized，” said University of Alberta researcher Dr.Takahiko Masuda.” A person’s culture plays a very strong role in determining how he will read emotions and needs to be considered when interpreting the facial expressions.”

These cultural differences are even noticeable in computer emoticons(情感符号)，which are used to convey a writer’s emotions by email and text message. The Japanese emotions for happiness and sadness vary in terms of how the eyes are drawn ，while the American emotions vary with the direction of the mouth. In the United States the emoticons∶)and∶­) show a happy face，whereas the emoticons∶(and∶­(show a sad face. However，the Japanese tend to use the symbol (‘­‘) to indicate a happy face，and (；­；) to indicate a sad face.

“We think it is quite interesting and appropriate that culture tends to mask its emotions. The Japanese would focus on a person’s eyes when detecting his or her emotions，as eyes tend to be quite subtle(微妙的)，”said Masuda. “In the United States，where an open emotion is quite common，it makes sense to focus on the mouth，which is the most expressive feature on a person’s face.”

小题1:The text mainly tells us that ________.

A．cultural differences are expressed in emotions

B．culture is a key to interpreting facial emotions

C．different emoticons are preferred in different cultures

D．people from different cultures express emotions differently小题2:Which emoticon is used by Americans to show a happy face?

A．(；­；)

B．∶­)

C．∶­(

D．∶(小题3:If a Japanese wants to detect whether a smile is true or false，he will probably________.

A．read the whole face

B．focus on the mouth

C．look into the eyes

D．judge by the voice小题4:The computer emoticons used by Americans show that________.

A．they express their feelings openly

B．they tend to control their emotions

C．they are good at conveying their emotions

D．they use simpler emotions to show their feelings

使用CNO邻区优化功能需要导入那些数据？（）

A.工程参数

B.无线参数

C.性能数据

D.单站数据