砖瓦是用含铁元素等杂质的粘土隔绝空气烧制而成的,当烧窑作业临近结束时,若用淋洒水

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问题:

砖瓦是用含铁元素等杂质的粘土隔绝空气烧制而成的,当烧窑作业临近结束时,若用淋洒水的办法来降低温度,窑内处于还原性气氛,砖块中的铁以氧化亚铁的形式存在,因而砖呈青色.若用捅开窑顶自然冷却的办法,砖就变成了红色.

(1)从化学角度看,砖瓦呈红色的原因是______.

(2)现有一块红砖,实验台上有浓H2SO4、3mol•L-1的盐酸、0.1mol•L-1的KSCN溶液,0.1mol•L-1的FeCl3溶液、0.01mol•L-1的NaOH溶液、蒸馏水等试剂,请选用中学化学常用仪器,设计一个实验,用最简捷的方法验证红砖中含有三价铁.(简述实验步骤,所用仪器、产生现象、所得结论)______.

考点:氧化亚铁氧化铁四氧化三铁氢氧化亚铁氢氧化铁
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以下哪项不是急性肝衰竭的发病基础

A.病毒性肝炎
B.化学药物中毒
C.休克
D.妊娠期
E.甲状腺功能亢进

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根据短文内容,从短文后的七个选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
Empathy
Last year, researchers from the University of Michigan reported that empathy, the ability to understand other people, among college students had dropped sharply over the past 10 years. _小题1:__ Today, people spend more time alone and are less likely to join groups and clubs.
Jennifer Freed, a co-director of a teen program, has another explanation. Turn on the TV, and you’re showered with news and reality shows full of people fighting, competing, and generally treating one another with no respect. _小题2:_
There are good reasons not to follow those bad examples. Humans are socially related by nature. 小题3:__ Researchers have also found that empathetic teenagers are more likely to have high self-respect. Besides, empathy can be a cure for loneliness, sadness, anxiety, and fear.
Empathy is also an indication of a good leader. In fact, Freed says, many top companies report that empathy is one of the most important things they look for in new managers. _小题4:_ “Academics are important. But if you don’t have emotional (情感的) intelligence, you won’t be as successful in work or in your love life,” she says.
What’s the best way to up your EQ (情商)? For starters, let down your guard and really listen to others. __小题5:__
To really develop empathy, you’d better volunteer at a nursing home or a hospital, join a club or a team that has a diverse membership, have a “sharing circle” with your family, or spend time caring for pets at an animal shelter.
A. Everyone is different, and levels of empathy differ from person to person.
B. That could be because so many people have replaced face time with screen time, the researchers said.
C. “One doesn’t develop empathy by having a lot of opinions and doing a lot of talking,” Freed says.
D. Humans learn by example—and most of the examples on it are anything but empathetic.
E. Empathy is a matter of learning how to understand someone else—both what they think and how they feel.
F. Good social skills—including empathy—are a kind of “emotional intelligence” that will help you succeed in many areas of life.
G. Having relationships with other people is an important part of being human—and having empathy is decisive to those relationships.
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请根据如图显微镜图示,结合有关操作技能,回答下列相关问题:

(1)与图中数码③⑥相对应的结构名称分别是:______.

(2)用低倍镜观察菠菜叶片横切标本时,若想对选择的物像作进一步细致观察,应该怎样调试显微镜?

(3)通过显微观察比较发现,人体口腔上皮细胞比菠菜叶肉细胞缺少哪些结构?

(4)为了便于显微观察,必须限制草履虫的运动速度.你在实验中采取了什么措施?

(5)某同学观察脊髓横切面标本时,装上目镜和物镜,放好玻片标本,观察时,却发现视野漆黑一片.请你帮助分析说明可能的原因:

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王霸之辩

题型:填空题

接近型行程开关的类型有:()。

A、霍尔元件

B、光电开关

C、电磁感应开关

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