You can tell a lot about people by looking at their hair — not just whether they brush, spray or blow-dry. Scientists have found a way to use hair to figure out where a person is from and where that person has been. The finding could help solve crimes, among other useful applications.
Water is central to the new technique. The liquid makes up more than half an adult human’s body weight. Our bodies break water down into hydrogen(氢) and oxygen. Atoms of these two elements end up in our tissues, fingernails, and hair.
But not all water is the same. Hydrogen and oxygen atoms can vary in how much they weigh. In the case of hydrogen, for example, there are three types according to their weights. Each type is called a hydrogen isotope(同位素). And depending on where you live, tap water contains different isotopes.
Can hair record this information? That’s what James R. Ehleringer, an environmental chemist at the University of Utah, wondered. To find it out, he and his colleagues collected hair from hair stylists in 65 cities across the United States. Even though people drink a lot of bottled water these days, the researchers have found that people’s hair has the same isotopes as found in local tap water. That’s probably because people usually cook their food with the local water.
Authorities can now use the information to analyze hair samples from criminals or crime victims and narrow their search for clues. For example, one hair sample used in Ehleringer’s study came from a man who had moved from San Francisco to Salt Lake City. As his hair grew, it reflected his change in location.
1.What do we know about the hydrogen isotopes according to Paragraph 3?
A. They are classified by size.
B. Each type of them differs in weight.
C. They can improve the quality of tap water.
D. Some of them cannot combine with oxygen.
2.Why is it possible to know where people are from by analyzing their hair?
A. People use the same bottled water.
B. People wash their hair in different ways.
C. People’s hair is affected by the weather of the places they stay.
D. People’s hair indicates the type of water in the places they stay.
3.The last paragraph is mainly to show _______.
A. how to recognize criminals B. how to collect hair samples
C. the usefulness of hair analysis D. the process of Ehleringer’s study
4.Which of the following can be the best title for the passage?
A. Water composition B. Change your hair
C. Hair detectives D. No way out
科目:高中英语 来源: 题型:阅读理解
查看答案和解析>>
科目:高中英语 来源:华大新高考联盟2017届高三5月教学质量测评英语试卷 题型:完形填空
After spending a long night drying the day before,I left the hotel in Wild Rose around 5:30 a. m. to attend a funeral in Green Bay. About half an hour into my journey,I heard a __ noise coming from my front tire. By 7 a. m. , I still had 70 miles __ me,but the noise was so loud that I knew I had no choice but to ___
It was so early in the morning that I __ there was little chance anyone in such a tiny town could help. __ I tried my luck at a vehicle __ shop which happened to be open then. Giving me a glance, the __ owner asked why I was so dressed up, and I explained my __. He checked out the car and told me what he had __ : the wheel bearing was failing.
Fixing it would take a few hours, but there was no possibility that the car would __ that distance without taking any measures. I started __ my brains for a spare plan. Could I rent a car? The man went to check at the store across the street, but its only rental car wasn’t __.
I must have looked pretty upset at that time because he then reached into his __, pulled out the keys to his own vehicle and said, “Take my truck, fill it up with gas and get going.” With a smile, he __ that the truck could go 120 miles per hour if needed.
We had met just 10 minutes before and even didn’t know each other’s __, but he insisted. I jumped into his Chevrolet Silverado and __ towards the funeral. When I returned to the garage several hours later with a __ heart, I chatted with the kind owner for a while. The 74-year-old __ turned a terrible day into a good one with a great __ —A random act of kindness may bring us __. So just be kind and help if you can.
1.A. familiar B. regular C. funny D. strange
2.A. before B. behind C. under D. beyond
3.A. wait B. stop C. continue D. rest
4.A. doubted B. wondered C. sensed D. regretted
5.A. Therefore B. Still C. Besides D. Meanwhile
6.A. beauty B. sales C. toy D. repair
7.A. young B. aged C. selfish D. mean
8.A. dilemma B. choice C. plan D. decision
9.A. prayed B. misunderstood C. feared D. ignored
10.A. get it B. forget it C. catch it D. make it
11.A. beating B. striking C. hitting D. scratching
12.A. handsome B. famous C. practical D. available
13.A. file B. trunk C. pocket D. wallet
14.A. concluded B. added C. admitted D. predicted
15.A. names B. habits C. beliefs D. families
16.A. stepped B. marched C. headed D. sailed
17.A. broken B. heavy C. merciful D. thankful
18.A. repairman B. driver C. salesman D. porter
19.A. discovery B. lesson C. response D. influence
20.A. wisdom B. strength C. welfare D. courage
查看答案和解析>>
科目:高中英语 来源:2017届广东省揭阳市高三第一次模拟考试英语试卷(解析版) 题型:短文改错
假定英语课上老师要求同桌之间交换修改作文,请你修改同桌写的以下作文。文中共有10处语言错误,每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。
增加:在缺词处加一个漏字符号(∧),并在其下面写出该加的词。
删减:把多余的词用斜线(\)划掉。
修改:在错词下面划一横线,并在该词下面写出修改后的词。
注意:1. 每处错误及其修改均仅限一词;
2. 只允许修改10处,多者(从第11处起)不计分。
Last Friday, our school organized us to a fire station, what we had expected for several day. When we got there, the fire-fighters welcomed us but led us into an exhibition hall. There one of them delivered the lecture on fire control to us. After that, they show us how to operate a fire extinguisher, and even gave our chances to practise using it. Now, I dare say I can use it skillful! On our way home, we couldn’t help to talking about what we had experienced. We felt very happy and excited because we had gained so many knowledge about fire control and known what to do an emergency.
查看答案和解析>>
科目:高中英语 来源: 题型:阅读理解
Passage outline | Supporting details |
(68)Details of a behaviour disorder | A person may be considered to have a behaviour disorder when he behaves apparently (69)differentlyfrom others. |
Symptoms of a behavior disorder | Being(70)aggressiveand showing no mercy to animals and other people Tending to do damage to things around him Having little sympathy or concern for others Failing to(71)answerfor what he has done and not being honest Lacking the awareness of(72)obeying/observingrules and regulations Having difficulty concentrating on something for long |
Factors (73)resultingin behaviour isorders | Some outside forces may lead to a behaviour disorder. A genetic disorder giving rise to a behaviour disorder has also been found. |
(74)waysto deal with behaviour disorders | Behaviour treatment:diagnosing such a disorder (75)accuratelyand modifying the disordered behaviour in a rational way. Psychological treatment:attaching importance to improving the patient's emotional (76)health,thus,developing a proper self-esteem. |
Conclusion | A behaviour disorder isn't nearly (77)easyto diagnose from physical symptoms,but it can be dealt with in behaviour and psychological ways. |
查看答案和解析>>
科目:高中英语 来源: 题型:选择题
A. | It never occurred to | B. | That never occurred to | ||
C. | It never occurred with | D. | That never occurred for |
查看答案和解析>>
科目:高中英语 来源: 题型:选择题
A. | Take it or leave it | B. | Can't complain too much | ||
C. | Go ahead | D. | Cheer up |
查看答案和解析>>
科目:高中英语 来源:2016-2017学年江西省南昌市高二上学期期末考试英语试卷(解析版) 题型:短文改错
此题要求改正所给短文中的错误。文中共有10处语言错误,每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。请按下列要求改正:
增加:在缺词处加一个漏字符号(^),并在其下面写出该加的词。
删除:把多余的词用斜线(﹨)划掉。
修改:在错的词下划一横线,并在该词下面写出修改后的词。
注意:1.每处错误及其修改均仅限一词;
2.只允许修改10处,多者(从第11处起)不计分。
Today is Tom’s 70th birthday, but there is anybody with him. He feels very disappointing. His sons didn’t care for him on this special day. Although the cakes are very delicious, but he doesn’t want to touch it. He just wants his children come and see him. Nowadays, many young people are so busy and independent which they seldom visit their parents. But blood is thick than water. Our dear parents brought us up for a lot of difficulty. Thus, we should and must bring happy to them when they become old.
查看答案和解析>>
湖北省互联网违法和不良信息举报平台 | 网上有害信息举报专区 | 电信诈骗举报专区 | 涉历史虚无主义有害信息举报专区 | 涉企侵权举报专区
违法和不良信息举报电话:027-86699610 举报邮箱:58377363@163.com