炸药中( )是我国矿山最广泛使用的工业炸药。A.硝酸铵类炸药 B.硝化甘油炸药 C

题型:单项选择题

问题:

炸药中( )是我国矿山最广泛使用的工业炸药。

A.硝酸铵类炸药

B.硝化甘油炸药

C.乳化炸药

D.水胶炸药

考点:安全工程师安全生产技术安全生产技术
题型:单项选择题

Katherine Com male is an 11-year-old girl from Pennsylvania. At the age of five she began raising money to buy nets for children in Africa to help stop the spread of malaria(疟疾).

When she was five, Katherine learnt about malaria in Africa. She learnt that every 30 seconds a child died from this disease. She, also learnt that people wouldn’t get that disease if they had enough bed nets. “I was really sad to learn that a child died every half a minute because of malaria.” Says Katherine, “I wanted to send nets right away, so that’s what I did.”

Five-year-old Katherine made presentations at churches and schools. She told students and others how important bed nets were for Africans. After people heard the presentations, many of them donated money. Katherine sent the money to NBN. NBN is an organization that sends bed nets to Africa.

Besides, every holiday Katherine makes something called “ net gift certificate” with the help of her friends and brothers. On each l0-dollar certificate there is a message. It explains that a bed net would be sent to Africa. When more certificate orders come, Katherine gets help from students in her school.

Katherine has helped to raise $200,000 for NBN. “It makes me proud to help African children. I wont stop working until everyone in Africa has a bed net.” says Katherine.

小题1:Which of the following is TRUE according to the passage?

A.When Katherine was six, she began helping children in Africa.

B.Katherine learnt that two children died from malaria one minute.

C.Katherine did a lot and helped to raise $ 20,000 for NBN.

D.Katherine’s parents helped her make “bed net gift certificate”.小题2:In Paragraph 4, “It” refers to “       ”.

A.a 10-dollar note

B.a gift certificate

C.an organization

D.a message小题3:From the passage we know Katherine did the following EXCEPT   _______.

A.raisinga great deal of money for NBN

B.givingpresentations at churches and schools

C.explainingthe importance of nets for Africans

D.ordering people to learn to use the nets well小题4:It can be inferred from the passage that         .

A.Katherine’s work is very helpful and meaningful

B.thespread of malaria in Africa will be more serious

C.everychild in Africa gets a net with Katherine’s help

D.Katherinehas received much money from NBN

题型:单项选择题

(14分)某学校探究性学习小组对消毒液次氯酸钠(NaClO)的制备与性质等进行了探究。

甲同学:为制备消毒液,探究并制作了一种家用环保型消毒液(NaClO溶液)发生器,设计了如图所示的装置,用石墨作电极电解饱和氯化钠溶液。

请完成下列问题:若通电时,为使生成的Cl2被完全吸收,制得有较强杀菌能力的消毒液,则电源的a电极名称为                 极(填“正”、“负”、“阴”或“阳”);装置溶液中反应生成NaClO的离子方程式为:                         

乙同学:从某超市中查询到某品牌消毒液包装说明的部分内容,摘录如下:

主要有效成份为次氯酸钠,有效氯含量8000-10000mg/L。可用于各类家居用品、餐具、棉织衣物等的消毒,对彩色织物可能有褪色作用。切勿用于丝绸、毛、尼龙、皮革、油漆表面,勿用于铝、铜、碳钢制品。本品须密封,置阴凉暗处保存。

请完成以下实验探究过程:

I.阅读材料,根据学过的知识判断问题   

(1)室温条件下,该消毒液(NaClO)的不显中性的原因是(用离子方程式表示)

_____________________。

(2)该消毒液还具有的化学性质是_________(填序号)。

A.强氧化性   B.强还原性   C.不稳定性    D.漂白性    E.弱酸性

(3)从该消毒液的保存要求分析,导致其失效的主要原因是(用化学方程式表示)

_                   

II.确定要研究的问题

该消毒液对碳钢制品的腐蚀原理。

III.设计方案,实施探究

(1)用烧杯取少量样品,将一颗光亮的普通碳钢钉放入烧杯,浸泡一段时间。

预期的实验现象是_________________________________。

(2)为了进一步探究铁钉在该漂白剂(NaClO)溶液中的腐蚀原理,丁同学设计了如下图实验装置,写出碳(C)极上发生的电极反应式:                             

题型:单项选择题

一般而言,公司的边际资本成本随着追加筹资金额的增加而逐渐()。边际投资报酬率则会随投资规模的上升而逐渐()。

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经过调查,发现行政案件有哪些情形的,经公安派出所或者县级公安机关办案部门以上负责人批准,终止调查?(5分)

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以生产企业为例,面向科室的管理称 【12】 层管理。

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