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【题目】下列除去杂质的方法正确的是( )
①除去乙烷中少量的乙烯:光照条件下通入Cl2,气液分离
②除去乙酸乙酯中少量的乙酸:用饱和碳酸钠溶液洗涤,分液、干燥、蒸馏
③除去CO2中少量的SO2:气体通过盛有饱和碳酸钠溶液的洗气瓶
④除去乙醇中少量的乙酸:加足量生石灰,蒸馏
A.①② B.②④
C.③④ D.②③
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【题目】某XY型性别决定的植物花色遗传中,常染色体基因D决定花色素的生成,X染色体上的基因H和h分别使花色呈现橙色和黄色,不能生成色素时花为白色。现将纯合白花雄株和纯合黄花雌株杂交,后代中有橙花植株。请回答下列问题:
(1)F1中雌株的基因型及雄株的表现型分别为 。让F1 雌雄株杂交得到F2,F2中橙花∶黄花∶白花比例为 。F2代中黄花植株的基因型有__________种。
(2)请利用纯合品系,设计杂交方案,探究 F2 中白花雌株的基因型:
①让F2 白花雌株与纯合 杂交;
②观察并统计后代的表现型,预期白花雌株的基因型。
如果 ;
如果 。
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【题目】近年来,广东省茂名市以建设幸福和美新农村为目标,积极探索农村精神文明建设的新模式,打好制度建设、主题活动和民生建设“三张牌”,大大改善了农村环境面貌和农民精神风貌,推动了社会主义新农村的新发展。在全省农村精神文明建设工作经验交流会和全省县级文明城市创建工作动员大会上,茂名市的做法被列为成功经验进行交流,受到与会各方的高度评价。
(1)如果你参与了此次交流会,你将会从茂名市的做法中获得哪些成功经验?
(2)结合材料,说明茂名市积极探索农村精神文明建设的新模式的意义。
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【题目】A
Buildings crashed to the ground in seconds. Thousands of people lost their lives in a flash. Since they were told an earthquake would hit Tokyo around September 16, Japanese people haven’t been able to get these thoughts out of their minds.
They heard the news from Yoshio Kushida, a researcher who used radio waves to predict that an earthquake would strike with a magnitude(量级) of at least seven."It would be terrible not to warn people of a possible disaster in case a quake actually occurs, "he said.
His warning had a big effect. Frightened Tokyo people have been stocking up on water, food and candles in preparation for the terrible day.
But Kushida hasn’t had much support from the experts. At present, predicting earthquakes is thought to be impossible. No one can tell exactly where or when the next major earthquake will occur. An earthquake begins tens of miles below the earth’s surface: it’s too faraway to see.
Ancient Chinese and Italian scientists forecast earthquakes by special "earthquake clouds". They found that a week before an earthquake, there were often strange clouds — shaped like snakes, waves or feathers — in the sky. They thought the clouds might come from a gas produced underground by an earthquake.
People also used to watch animals to see if earthquakes were coming. When they saw birds fly away suddenly, dogs barking violently or fish jumping out of the water, they told people to leave the area. Some scientists believed animals had a sharper sense of changes taking place underground.
But the ancient methods were not reliable enough. Nowadays, scientists use special instruments to predict earthquakes more precisely(精确地).
Satellite systems are very useful: they record small changes in the earth’s magnetic fields(磁场) which help show where and when an earthquake may strike.
【1】Since they were told an earthquake would hit Tokyo, Japanese people__________.
A. have had no mind to do their work
B. have always thought great damage it may cause
C. have almost forgotten about it
D. have bought all the foods in the markets
【2】 Which of the following is TRUE?
A. Tokyo people were surprised at the warning.
B. Great disasters would happen if people are not warned of before an earthquake.
C. Predicting earthquakes is completely impossible at present science level.
D. According to ancient people,before an earthquake we can see strange clouds anywhere.
【3】Which is the best way to predict earthquakes nowadays?
A. Watch animals. B. By special"earthquake clouds".
C. Use satellite systems. D. There’s no way.
【4】Which can be the best title for the passage?
A. Earthquake prediction. B. Magnetic fields.
C. Earthquakes. D. An earthquake in Japan.
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【题目】书面表达
最近来自美国的外教史密斯先生任你们班的口语老师。请你根据提示信息,用英语写一篇短文,介绍这位新老师。
外貌 | 戴眼镜;年轻、英俊;中等身材 |
性格 | 幽默;外向;乐于助人 |
教学方面 | 知识丰富;课堂生动、有趣 |
与学生的关系 | 与学生关系融洽,在学习方面要求严格 |
参考词汇:中等身材 be of medium height
注意:1. 词数:100左右;
2. 可适当增加细节,以使行文连贯;
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【题目】书面表达(满分20分)
假如你是李明,上周你们学校请地震专家王教授来做了一次关于地震自救知识的讲座。请你就以下要点写一篇英语作文介绍这次讲座。
内容要点:
1. 介绍学习地震防护知识的重要性。
2. 演示如何在地震中保护自己。
3. 自己的感想……
注意:词数100左右。
参考词汇:预防措施precautionary measures
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【题目】金属镍有广泛的用途。粗镍中含有少量Fe、Zn、Cu、Pt等杂质,可用电解法制备高纯度的镍,下列叙述正确的是(已知:氧化性Fe2+<Ni2+<Cu2+)( )
A.阳极发生还原反应,其电极反应式:Ni2++2e-==Ni
B.电解过程中,阳极质量的减少与阴极质量的增加相等
C.电解后,溶液中存在的金属阳离子只有Fe2+和Zn2+
D.电解后,电解槽底部的阳极泥中只有Cu和Pt
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【题目】家兔的黑色和褐色是一对相对性状。现有甲、乙、丙、丁4只家兔,其中甲、乙是雌兔,丙和丁是雄兔。甲、乙、丙全为黑色,丁为褐色。已知甲和丁交配的后代全部是黑色子兔,乙和丁交配的后代有褐色子兔。请回答下列问题:
(1)黑色和褐色这两种体色中,显性的是 色。
(2)甲、乙、丁三只兔的遗传因子组成分别是(用F、f表示)
甲: ;
乙: ;
丁: ;
(3)如何鉴别丙兔是纯合子还是杂合子?
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【题目】完成句子
1. 麦克又矮又胖,这使他在班上很显眼。
Mike is short and fat, __________________in the class.
2. 那边在树下读书的男孩是谁?
Who is the boy__________________over there?
3. 这就是那位父母亲在地震中丧生的年轻人。
This is the young man__________________in the earthquake.
4. 英语是你这些年里要学的最难的一门学科。
English is the most difficult subject ____________________.
5. 任何没有通过考试的人都应该受到惩罚。
Anyone________________should be punished.
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【题目】七选五
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。
China is making great effort to protect its cultural relics. In early May, State Administration of Cultural Heritage (SACH) added 1,943 unmovable cultural relics sites to the list. So the number of these sites on this list will increase to 4,295. 1
The newly added sites were reviewed(评审) by more than 130 experts. They spread around Shanxi, Henan, Hunan, Hebei and Jiangsu provinces, including 795 pieces of ancient architecture and 516 ancient ruins. 2
In an interview, the head of the SACH said that new types of cultural relics sites have been newly listed to get protection at first, including industrial relics, rural architecture and cultural landscapes. 3 For example, some are in the north China’s Inner Mongolia Autonomous Region.
Despite great achievements during the years of effort, problems still exist. 4 Historic relics get stolen and antiques are taken abroad secretly.
The head of the SACH said that people has faced a challenge to the protection of cultural relics for a long time. So, balancing the relationship between economic development and protection of history is important. ____5____ He also used good examples of protection, describing how some cultural relics sites have become education bases for young people and popular tourist places, where a lot of people spend their holiday.
A. All of them need protecting as quickly as possible.
B. They also include outstanding modern architecture.
C. The SACH has found a total of 4,295 cultural relics.
D. Many relics have been destroyed in the process of urban construction.
E. Cultural relics sites should become positive factors to improve economic development.
F. When talking about protecting the cultural relics, the head of SACH ordered some to be saved.
G. Moreover, many of the new sites also include valuable cultural relics from ethnic minority regions(少数民族地区).
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