简述启蒙运动产生的原因。

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问题:

简述启蒙运动产生的原因。

考点:世界近代史世界近代史题库
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2013年1月27日百度新闻资讯中报道,活性氧化锌是一种多功能性的新型无机材料,其颗粒大小约在1~100纳米。云南化工冶金研究所采用湿化学法(NPP-法)制备纳米级活性氧化锌,可用各种含锌物料为原料,采用酸浸出锌,经过多次净化除去原料中的杂质,然后沉淀获得碱式碳酸锌,最后焙解获得活性氧化锌,化学工艺流程如下:

(1)通过________可以检验流程中滤液2中含有Na

(2)上述流程图中pH=12的Na2CO3溶液中c(CO32- )=0.50 mol/L,c(HCO3- )=1×102 mol/L,则c(Na)∶c(OH)=________。

(3)“溶解”后得到的酸性溶液中含有Zn2SO42- ,另含有Fe2、Cu2等杂质。先加入________(填“Na2CO3”或“H2SO4”)调节溶液的pH至5.4,然后加入适量KMnO4,Fe2转化为Fe(OH)3,同时KMnO4转化为MnO2。经检测溶液中Fe2的浓度为0.009 mol·L1,则每升溶液中至少应加入________mol KMnO4

(4)已知常温下,Cu(OH)2的溶度积常数Ksp=2×1020。溶液中杂质Cu2浓度为0.002 mol·L1,若要生成沉淀,则应调节溶液的pH大于________。

(5)“沉淀”得到ZnCO3·2Zn(OH)2·H2O,“煅烧”在450~500 ℃下进行,“煅烧”反应的化学方程式为:_____________________________________。

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我国和西方的公务员制度在本质上是无差别的。()

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Does a drink a day keep heart attacks away? Over the past 20 years, numerous studies have found that moderate alcohol consumption, s ay, one or two beers, glasses of wine or cocktails daily helps to prevent coronary heart disease. Last week a report in the New England Journal of Medicine added strong new evidence in suport of that theory. More important, the work provided the first solid indiction of how alcohol works to protect the heart.In the study, researchers from Boston’s Brigham and Women’s Hospital and Harvard Medical School compared the drinking habits of 340 men and women who had suffered recent heart attack with those of healthy people of the same age and sex. The scientists found that people who sip one to three drinks a day are about half as likely to suffer heart attacks as nondrinkers are. The apparent source of the protection: those who drank alcohol had higher blood levels of highdensity lipoproteins, the socalled good cholesterol, which is known to prevent heart disease.

As evidence has mounted, some doctors have begun recommending a daily drink for patients of heart diseases. But most physicians are not ready to reommend a regular happy hour for everyone. The risks of teetotalling(绝对戒酒) are nothing compared with the dangers of too much alcohol, including high blood pressure, strokes and liver troubles—not to mention violent behaviour and traffic accidents. Moreover, some studies suggest that even  moderate drinking may increase the incidence of breast and colon cancer. Until there is evidence that the benefits of a daily dose of alcohol outweigh the risks, most people won’t be able to take a doctor’s prescription to the neighbourhood bar or liquor store.

1.The medical article quoted in the first paragraph indicates            .

the way in which alcohol can help the heart      

how a couple of cocktails daily can stop heart problems

why alcoholic drinks are dangerous to one’s health 

that reports on the advantages of alcohol were misled

2.Experiments showed that nondrinkers had .

A.larger amounts of good cholesterol

B.smaller amounts of good cholesterol

C.higher blood pressure

D.lower blood pressure3.According to the passage, moderate drinking            .

is recommended by most doctors for heart patients    

should be allowed on prescription

is still not medically advisable                     

is not related to liver problems

4.The main theme of this passage is .

the change in recent drinking habits                

the connection between cancer and alcohol

whether moderate drinkers outlive nondrinkers       

whether alcohol may be good for one’s health

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在价值工程活动中,当采用功能成本法求得评价对象的价值系数小于1时,应以( )为改进方向。

A.剔除过剩功能及降低现实成本

B.剔除重复功能及降低现实成本

C.剔除过剩功能及提高现实成本

D.剔除重复功能及提高现实成本

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磁轭铁片压紧常采用哪些方法?

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