Most people know precious gemstones (宝石) by their appearances. An emerald flashes deep green, a ruby seems to hold a red fire inside, and a diamond shines like a star. It’s more difficult to tell where the gem was mined, since a diamond from Australia or Arkansas may appear the same to one from the Democratic Republic of the Congo. However, recently, a team of scientists has found a way to identify a gemstone’s origin.
Beneath the surface of a gemstone, on the tiny level of atoms and molecules（分子）, lie clues (线索) to its origin. At this year’s meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers (激光) to clarify these clues and identify a stone’s homeland. McManus directs scientific research at Materialytics, in Killeen, Texas. The company is developing the technique. “With enough data, we could identify which country, which mining place, even the individual mine a gemstone comes from,” McManus told Science News.
Some gemstones, including many diamonds, come from war-torn countries. Sales of those “blood minerals” may encourage violent civil wars where innocent people are injured or killed. In an effort to reduce the trade in blood minerals, the U.S. government passed law in July 2010 that requires companies that sell gemstones to determine the origins of their stones.
To figure out where gemstones come from, McManus and her team focus a powerful laser on a small sample of the gemstone. The technique is called laser-induced breakdown spectroscopy. Just as heat can turn ice into water or water into steam, energy from the laser changes the state of matter of the stone. The laser changes a miniscule part of the gemstone into plasma, a gas state of matter in which tiny particles（微粒）called electrons separate from atoms.
The plasma, which is superhot, produces a light pattern. (The science of analyzing this kind of light pattern is called spectroscopy.) Different elements produce different patterns, but McManus and her team say that gemstones from the same area produce similar patterns. Materialytics has already collected patterns from thousands of gemstones, including more than 200 from diamonds. They can compare the light pattern from an unknown gemstone to patterns they do know and look for a match. The light pattern acts like a signature, telling the researchers the origin of the gemstone.
In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. For gemstones like emeralds and rubies, the technique proved successful for 98 out of every 100 stones. The scientists need to collect and analyze more samples, including those from war-torn countries, before the tool is ready for commercial use.
Scientists like Barbara Dutrow, a mineralogist from Louisiana State University in Baton Rouge, find the technique exciting. “This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.
1.We learn from Paragraph 1 that __________.
A. an emerald and a ruby are names of diamonds.
B. it’s not difficult to tell where the gem was mined.
C. appearances help to identify the origin of gemstones.
D. diamonds from different places may appear the same.
2.Why did the U.S. government pass law that requires companies selling gemstones to determine the origins of their stones?
A. To look for more gemstones.
B. To encourage violent civil wars.
C. To reduce the trade in blood minerals.
D. To develop the economy.
3.Which of the following facts most probably helps McManus and her team in identifying the origin of stones?
A. Heat can turn ice into water or water into steam.
B. Gemstones from the same area produce similar light patterns.
C. Laser can change a miniscule part of the gemstone into plasma.
D. Materialytics has already collected patterns from thousands of gemstones.
4.From the last two paragraphs, what can be inferred about the laser technique?
A. It is ready for commercial use.
B. People can use the new tool to find more gemstones.
C. It can significantly reduce the gemstones trade in blood minerals.
D. It will bring about a revolutionary change in identifying the origin of minerals.
5.The author wrote this passage mainly to __________.
A. tell us how to identify the origin of diamonds.
B. introduce a laser technique in identifying a stone’s origin
C. prove identifying the origin of gemstones are difficult
D. attract our attention to reducing trade in blood minerals
Primary schools could be told to remove some traditional subject-based lessons and replace them with “personal development” classes to encourage children to improve their social and practical skill. Parents, teachers and pupils, who took part in the investigation carried out for the biggest ever official review of the primary curriculum, argued that the number of subjects taught to very young people should be reduced.
The review, being conducted by the government’s school’s director Sir Jim Rose, will consider how to redesign the primary school day to handle concerns that too many pupils leave primary school unable to read, write and do maths at the level expected of them. It will also address criticisms that pupils are expected to study so many subjects there is little time for creative learning.
The 60 focus groups brought together 1,500 parents, pupils and school staff and is expected to heavily influence the thinking of the Rose review, which the government is promising to back. Instead of a broad range of subjects, pupils should study in-depth literacy and maths lessons alongside a more creative curriculum that encourages pupils to develop personal, learning and thinking skills, they say. Such lessons might include “healthy lifestyles, sex and relationships education, drugs and alcohol education”.
“Child and personal development as priorities have been shamefully neglected in recent years in the rush to hit targets in the basics.” John Bangs, head of education at the National Union of Teachers, said, “The worst thing would be to evaluate child development through the current high stakes testing system. That would weaken the capacity of teachers to meet children’s unique needs.”
However, the shadow schools minister, Nick Gibb, said, “If lessons on lifestyle are given the same status as traditional subjects, it is the most disadvantaged children who will be worst affected.” “Children are not able to personally develop and succeed in the future if they don’t have a grasp of basic subjects such as maths and English early on in primary school. Removing high requirement from the primary curriculum would increase the inequality gap between less well-off pupils and the rest.” Nick added. A spokeswoman for the Department for Children, Schools and Families (DCSF) said, “This is a summary of stake holder’s view, not the views of the Qualifications and Curriculum Authority or the DCSF, and has been submitted to Sir Jim Rose’s review as evidence to consider.”
1. According to the focus groups, the result of learning too many subjects is most likely to be that __________.
A. children may not have any freedom
B. children may not have enough time for personal interest
C. children may not know anything outside the classroom
D. children may not have creative ability
2.Which of the following is False about the review conducted by Sir Jim Rose?
A. It will greatly influence the country’s future primary curriculum.
B. It will remove high requirement from the primary curriculum.
C. It is supported by the Qualifications and Curriculum Authority or the DCSF.
D. It needs to take fully into account varied views from the society.
3.John Bangs’s attitude towards the current high stakes testing system is __________.
A. negativeB. positive
C. uncertainD. cautious
4.According to Nick Gibb, grasp of basic subjects early on in primary school is important for _______.
A. the primary curriculum reform
B. children’s development in the future
C. children’s educational equality
D. increasing the children’s confidence
Below are some classified ads from an English newspaper.
Classified ads FOR DIRECT CLASSIFIED SERVICE CALL 800—0557 10A.M.-4P.M. MONDAY-FRIDAY | ||
FOR SALE COME to moving sale----Plants, pottery, books, clothes, etc, Sat, Dec. 14#----9a.m.-5p.m.1612 Ferndale, Apt. I.800-4696.
USED FUT COATS and JACKETS. GOOD condition. $30-$50. Call 800-0436 after 12 noon.
MOVING: Must sell. TV21”, $50; AM/FM radio A/C or battery, $15; cassette tape recorder, $10. Call Jon or Pat, 800-0739 after 5 p.m. or weekends.
SHEEPSKIN COAT: man’s, size 42, I year old. $85. After 6 p.m.,. 800-5224. LOST AND FOUND FOUND: Cat, 6 months old, black and white markings. Found near Linden and South U. Steve. 800-4661.
LOST: Gold wire rim glasses in brown case. Campus area. Reward, Call Gregg 800-2896.
FOUND: Set of keys on Tappan near Hill intersection. Identify key chain. Call 800-9662.
FOUND: Nov.8th----A black and white puppy in Packard-Jewett area. 800-5770. | PERSONAL OVERSEAS JOBS---Australia, Europe, S. America, Africa. Students all professions and occupations, $700 to $3000 monthly. Expenses paid, overtime. Sightseeing, Free information at STUDENTS’UNION.
THE INTERNATIONAL CENTER plans to publish a booklet of student travel adventures. If you like to write about your foreign experiences, unusual or just plain interesting. Call us (800-9310) and ask for Mike or Janet.
UNSURE WHAT TO DO? Life-Planning Workshop, Dec. 13th -15th, Bob and Margaret Atwood, 800-0046. ROOMMATES FEMALE ROOMMATE WAMTED: Own room near campus. Available December 1st. Rent $300 per month until March 1st. $450 thereafter. Call Jill for details, 800-7839.
MEED PERSON to assume lease for own bedroom in apt. near campus, ＄’380/mo. starting Jan. 1st. Call 800-6157 after 5p.m.. | DOMESTIC SERVICE EARLY HOUR WAKE-UP SERVICE: For prompt, courteous wake-up service, call 800-0760.
HELP WANTED BABYSITTER—MY HOME If you are available a few hours during the day, and some evenings to care for 2 school-age children, please call Gayle Moore, days 800-1111, evenings and weekends 800-4964. PERSONS WANTED for delivery work, Own transportation. Good pay. Apply 2311 E. Stadium. Office 101, after 9 a.m.
TELEPHONE RECEPTIONIST WAMTED. NO experience necessary. Good pay. Apply 2311 E. Stadium. Office 101, after 9 a.m. WAITRESS WANTED: 10 a.m.-2 p.m. or 10:30 a.m.-5 p.m. Apply in person. 207 S. Main, Curtis Restaurant.
HELP WANTED for house cleaning |
1.Where will you post a notice if you need someone to look after your children?
A.PERSONAL B.HELP WANTED
C.DOMESTIC SERVICE D.ROOMMATES
2.To have your travel notes published, you may contact .
A. Students’ Union B. Gayle Moore
C. The International Center D. Life Planning Workshop
3.If you want to have someone wake you up in the morning, you may call .
A.800-5224 B.800-5770
C.800-7839 D.800-0760
I finished my last evening shift of the week and could hardly wait to get home. I took off my nursing shoes, relaxed and then said goodnight to the rest of the girls and headed out of the door.
It was so cold and I could see the ice crystals in the air. As I approached my car, I saw one of my coworkers standing by the bus stop. I thought it would only take a couple of extra minutes to give her a ride home, and besides, it was too cold to be standing outside on the coldest night in January.
We chatted as I drove and before we knew it, we arrived at her house. As she headed up the steps to her door she turned around. “Do you know how to get to your house from here?” “How hard can it be? I’ll just backtrack the way I came.”
I started driving. Nothing looked familiar, but at first that didn’t bother me since I’d never been to this neighborhood before. I kept driving, and soon I sensed that something was wrong. I recognized nothing, not the neighborhoods, not even the street names. My husband would be worried about me. I looked down at my watch. It was now 2:30. I’d left work at 11:30 pm.
I stopped my car. I thought I’d better take stock of my situation. My gas gauge (汽油表) was slowly going down. In total defeat I put my head down on the steering wheel and asked for help. I lifted my head. I saw a shadow down the road in front of me. It was a car. What was a car doing in the middle of nowhere at 2:30 in the morning?
Hesitantly, I got out of my car and knocked on the window of the other car. An elderly man slowly rolled his window down.
I said, “I’m lost and don’t know how to get back into town.”
In silence, he started driving. I drove behind him.
Finally I recognized a familiar street. As I turned to head home, I lost sight of my guiding angel. When I pulled into my driveway the warning light for my gas tank turned on.
1.Why did the writer stop her car?
A. To consider and judge the situation.
B. To check whether there was gas.
C. To prevent the car breaking down.
D. To turn to somebody for help.
2.When the writer got home, _______.
A. she thanked the old man very much
B. her husband was waiting for her anxiously
C. the oil in her car was just going to run out
D. she was totally frozen on the cold night
3.What might be the suitable title for the passage?
A. Keep up and you will succeed at last.
B. Meeting a friendly old man in trouble.
C. Giving a ride to my coworker at night.
D. Losing my way on a cold winter night.
“Kevin, we are getting a divorce,” said my mother. My heart plunged. I was 9 years old and I thought that my life was going to . My brother and I were going to move with my mother to southern California. My dad was to in New Jersey because of work. My family was splitting apart.
Now that my mom is a single parent, I do my own , make dinner and do extra chores around the house. it was hard at first, I now recognize the positive that this responsibility had on me. My mother gave me these chores and duties so that I would learn to become and trustworthy.
I strive to display these in all aspects of my life, and have seen the benefits. When I was only 11 years old, my told me that he was selecting me as soccer team captain because of my determination and ability to get my teammates to themselves. We lost the championship, but I won the play award for keeping my team together.
I am always to be an individual and not participate in anything that I feel is wrong. I am, for example, extremely proud of my decision not to drink alcohol. , I don’t feel the need to drink to have fun, and I stand by my decision even when others try to me.
My mom and dad both found new and happily remarried. I am close to my father, even though he lives 4,800 km away. I thought my parents’ divorce was going to be the worst thing that happened to me. Ironically (讽刺的是), it turned out to be the . I wasn’t willing to let it ruin my life without putting up a fight, and was my family.
At age 9, I struggled with the confusion and of divorce. Today, at age 16, I understand that can bring opportunity and success, and that hard work, determination and self-control can turn your worst time into your best time.
1.A. fall apart B. give away C. pick up D. take off
2.A. drop B. remainC. call D. break
3.A. housework B. farming C. cookingD. laundry
4.A. Although B. Because C. If D. Since
5.A. attitude B. experienceC. effect D. situation
6.A. self-centered B. self-absorbed C. self-disciplined D. self-concerned
7.A. skills B. difficulties C. emotions D. qualities
8.A. father B. headmaster C. brotherD. coach
9.A. enjoy B. teach C. prove D. push
10.A. fierce B. fair C. close D. decisive
11.A. determined B. reminded C. relieved D. amazed
12.A. FortunatelyB. SurprisinglyC. PersonallyD. Consequently
13.A. cheat B. pressure C. pleaseD. delight
14.A. families B. jobs C. kids D. partners
15.A. still B. not C. rarely D. less
16.A. never B. evenC. ever D. almost
17.A. best B. worst C. busiestD. first
18.A. so B. suchC. asD. neither
19.A. pain B. memory C. significanceD. emergency
20.A. barriers B. families C. parents D. routines
— Where were you last night? We had a wonderful party.
— Oh, ________ If you had called me, I wouldn’t have gone to the cinema.
A. What a shame!B. Who cares?
C. bad luck!D. What a coincident!
