Word Study to the Text. Comprehension Check:

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Comprehension Check:

Ex. Answer the following questions

1. What is the range of the engineer's functions?

2. Is the detailed knowledge of scientific concepts very important?

3. What knowledge and skills does the engineer require?

4. What are the professional requirements to the design engineer?

5. What are the production and construction engineers responsible for?

6. What specialists may be employed at a large plant?

7. What are the requirements to the sales engineer?

8. What knowledge does the engineer need when being in a

The Transistor

NATURE abhors a vacuum tube," cracked Bell Labs physicist John Pierce. So did almost everyone else by the 1940s. Sure, vacuum tubes boosted the power of the phone network's electrical signals, which weaken as they travel. But vacuum tubes were too bulky, unreliable and inefficient to support what AT&T expected to be a boom in demand for telecommunications after die end of World War II. So as peace loomed, in the summer of 1945, Bell Labs established a group to forge the future out of semiconductors, materials whose properties He midway between an electrical insulator's and a conductor's. In the fall of 1947, in a month long burst of inspiration. Bell scientists invented the device that came to embody, even create, the future. The tiny transistor changed the way we bank, drive, cook, communicate, listen to music, watch television and otherwise work, play and live.

The inventors were an unlikely trio. William Brattain was a farm boy and a born tinker. William Shoddey, hard-driving, ambitious and impatient, was named manager of semiconductor research in 1945. His ego would eventually fracture the team. "Whispering John" Bardeen, the low-key, famously self-eflacing theorist, would become the only person ever to win two Nobels in physics.

In 1925 a British scientist had theorized that if an electric field enveloped a semiconductor, then the semiconductor would conduct electricity differently. In some cases, it would amplify incoming current. That appealed to the Bell scientists charged with finding replacements for vacuum tubes. But the phenomenon remained maddeningly theoretical; try as they might, no one could make semiconductors

jack up a signal. Finally, in March 1946, Bardeen hit on the reason. Electrical fields were not having the desired effect on, say, a bar of silicon because the surface of the silicon is riddled with cul-de-sacs, he suggested, making it possible for electrons to enter but not to leave. The surface seemed to be positively charged on the outside, attracting electrons in, but negative on the inside, repelling them when they start to move. The electrons were stuck. As a result the flow of electrons— which is all a current is — could not increase. Applying an electric field did nothing.

For the next 20 months Bell's team turned to the most basic of research—the quantum properties of solids—as it sought ways to liberate the electrons in the semiconductor. "Without understanding solids from a quantum mechanical point of view," says William F. Brinkman, vice president of B&D at Bell Labs, "the transistor could not have been invented." On Nov. 17,1947, Brattain launched the experiments that would bring success. He began with a splash—literally: he bathed silicon in various electrolytes (liquids that contain electric charges), such as acetone and distilled water. The electrolytes changed the electrical properties of silicon's surface. When Brattain shined a light on the treated silicon, a larger current flowed than from untreated silicon (silicon was known to produce a current in response to light; today that is the basis for solar cells). Apparently, the electrolytes set up an

bulldozed the cul-de-sacs, allowing the electrons to escape.

On Nov. 21 Bardeen went to Brattain with a new

suggestion for making silicon amplify a signal "Come on, John!" Brattain exclaimed. "Let's go out in the laboratory and make it!" They put a drop of distilled water on a slab of silicon. They pushed a tungsten wire through the drop and onto the silicon. They used a battery to apply one volt to the drop, hoping to stir up the positive and negative charges in the silicon just below the wire. Current through the contact point increased 10 percent: positive charges in the distilled water pulled the silicon's electrons to the surface, making more electrons flow and thus amplifying the current. Carpooling home that evening, Brattain said he'd "taken part in the most important experiment cording to an AT&T oral history quoted in "Crystal Fire"

{352pages. W.W.Norton. $27.50), a new book on the transistor by Michael Biordan and Lillian Hoddeson. But hurdles remained. The

silicon boosted current only 10 percent, not enough to outdo vacuum tubes. Brattain and Bardeen tried every variation they could think of to better their results. Germanium instead of silicon. Gold foil instead of tungsten. A viscous liquid called glycol borate — "gu" — instead of distilled water. On Dec. 16 they jury-rigged their final contraption. "It was marvelous!" Brattain recalled: their transistor boosted power 450 percent. The key realization was that "holes"—weird quantum-mechanical entities that are the absence of electrons — carried current in silicon. When Bardeen returned home that evening, he mumbled to his wife, Jane, as she peeled carrots, "We discovered something important today."

But Shocldey was far from elated at Bardeen and Brattain's success. He argued that work he had done in 1945 had sparked their invention, but AT&T's lawyers had filed a patent only on Brattain and Bardeen's device. Shoddey worked obsessively on his own. On Jan. 23,1948, he had his brainstorm: a sandwich. The bread would be a sandwich. The bread would be semiconductor material with an excess of electrons; it was dubbed "n-type." The meat would be "p-type," with an excess of positively charged holes. When he attached wires and applied a voltage, holes streamed across the n-material into the p-area. His "junction transistor" amplified current just like Brattain and Bar-deen's "point-contact" transistor. He tinkered with it in total secrecy. The rift in the team was now a canyon. Bardeen, fed up with Shockley, resigned in 1951.

In 1952 Bell Labs offered to license the point-contact transistor for $25,000 against future royalties. They had few takers apart from a small Japanese start-up called Sony. Its first transistor radio sold, in 1954, for $49.95 (more than $300inl995 dollars). Bell Labs produce the point-contact transistor for 10 years. But 1954 production of the junction transistor ha overtaken it. In 1956 Brattain, Bardeen and Shoddey shared the Nobel in physics.

As the price of a transistor plunged—fix)! $45 to $2 in the 1950s to.00001 cent today-the applications mushroomed. In 1959 sales of solid-state transistors overtook sales of vacuum tubes, and there has been no going back. Before the transistor "the whole phone network was analog and the switches were electromechanical; the transistor changed that to digital transmissions and electronic switches," says Jan Ross, Bell Labs preside] from 1979 to 1991. Today transistors packed by the millions onto microprocessors run ca engines, cell phones, missiles, satellites, gas pumps, ATM machines, microwave ovens, computers, CD players and every other modem electronic toy and tool. In 1997 more than half a billion transistors will be manufactured. Every second.

THE TRANSISTOR. (Home Reading)

Vocabulary.

abhore - испытывать ужас

crack - разг.: отпускать шутки

boost - повышать (напряжение)

weaken - ослаблять

bulky - большой, громоздкий

unreliable - ненадежный

inefficient - неэффективный

boom - шумиха, бум, сенсация

loom - неясно вырисовываться

property - свойство

insulator - изолятор

burst - вспышка

inspiration - вдохновение

device - прибор

embody - воплощать, олицетворять

tiny - крошечный

bank - держать деньги в банке

unlikely - здесь: неправдоподобный

hard-driving - трудноуправляемый

fracture - разбить, сломать

whisper - шептать

low-key - незначимый, слабый

eflace?????

envelop - окружать

amplify - эл. усиливать

appeal - обращаться, взывать

be charged with - здесь: заняться

replacement - замещение, замена

jack up - здесь: уловить

desired - желаемый

bar - брусок

silicon - кремний

surface - поверхность

riddled - изрешеченный

cul-de-sac - тупик

charged - здесь: заряженный

attract - притягивать, привлекать

repel - отражать, отталкивать

be stuck - застрять

flow - поток

increase - увеличивать

apply - применять

solid - твердое тело

seek (sought, sought) - искать

liberate - высвобождать

launch - стартовать, начать

splash - всплеск; мн.ч. брызги

literally - в буквальном смысле слова

bathe - окунать

treat - обрабатывать, подвергать воздействию

current - ток

response - ответ

cell - здесь: батарейка

apparently - очевидно

set up - установить

bulldozed - выпущенный

escape - высвободить

suggestion - предложение

drop - капля

tungsten - вольфрам

wire - провод

stir up - здесь: возбуждать

below - ниже

quote - цитировать

boost - повышать

hurdless - препятствие, барьер

outdo - превзойти

foil - фольга

viscous - вязкий

liquid - жидкость

contraption - разг. странный прибор

recall - вспоминать

hole - дырка

weird - странный

entity - здесь: сущность

mumble - бормотать

elate - привести в восторг

spark - здесь: быть искрой (для)

obsessively - одержимо

excess - излищек, избыток

attach - прикреплять

stream - поток, струя

junction - скрепление

rift - трещина

fed up (with) - "сыт по горло"

resign - здесь: отойти от дел

royalties - авторские права

share - разделять

mushroom - амер.: быстро расти

ovеrtake - превзойти

switch - выключатель

digital - цифровой

transmission - трансмиссия, перенос

cell phone - сотовый телефон

missile - снаряд, ракета

satellite - спутник

pump - насос

microwave - микроволновый

toy - игрушка

tool - инструмент, орудие, средств

Comprehension Check.

Ex. Answer the following questions:

1. What is the function of vacuum tubes?

2. What for did Bell Labs establish a special group?

3. What do semiconductors serve for?

4. What did Bell Labs' scientists invent?

5. When did the team split up (распалась)? What was the reason of it?

6. What prize was the team awarded with in 1951?

7. What is a transistor?

8. What are the functions of transistors today?

Topics to discuss.

1. Vacuum tube.

2. Bell Labs' team of scientists. Their initial task.

3. An unlikely trio.

4. Their basic research.

5. Silicon amplifying signals.

6. Relationships between these three scientists.

7. Nobel prize shared by them.

8. The price of a transistor.

9. Changes brought by transistors.

Geoffrey Cowley, Anne Cowley

PORTABLE DATABASES CAN MAKE DOCTORS MORE EFFICIENT.

BUT THIS ONE HELPS THEM PRACTICE BETTER MEDICINE.

David Slawson was sitting at his desk one morning last February when a

collegue called him to tell that one of his patients was in the emergency

room (ER), suffering from pneumonia. The pateint, an otherwise healthy

43-year-old woman, was in no immediate dander, but the ER doctor wanted to

hospitalize her just to be safe. Few physicians would have stopped to

question whether hospital care actually benefits such a client. But

Slawson, a family practitioner at the University of Virginia, had an easy

way to find out. He grabbed the mouse on his computer and, with a few

clicks, pulled up a "prognosis calculator". By punching in basic facts

about the woman, he determined, that her odds of dying would be 2.2 times

HIGHER if she checked into the hospital (where germs are rampant and

medical errors possible) than if she recuperated at home. Shown that

number, the ER doctor quickly wrote a prescription and sent her on her way

- saving her insurer thousands of dollars and, in all likelihood, hastening

her recovery.

What Slawson had, and the emergency room didn't, is a new software

program called InfoRetriever. IR as compact enough to run on a palmtop PC,

yet potentially powerful enough to transform the practice of medicine.

Besides quantifying the advantages of different treatment strategies, it

calculates drug dosages, clarifies test results amd summarizes current

research findings on everything from arthritis to baby care. At Michigan

State University and the University of Virginia, some 200 physicians are

now road-testing the first palmtop version of InfoRetriever. And though

most have used it for less than a month, few would deny that it's making

better doctors of them. The program doesn't just enhance their efficiency.

As Slawson's experience suggests, it can improve their decisions.

Medical practice has never been quite the scientific endeavor we

imagine. Studies have shown repeatedly that doctors pay less attention to

research findings than to colleagues and drug-company representatives -

and that patients with identical conditions often receive radically

different treatments, depending on which clinic they visit. Reformers have

struggled since 1970s to promote a more consistent, "evidence-based" model

of care, but managing the relevant data has proven a daunting challenge. A

physician would have to skim thousands of articles a year to find the

clinically useful findings - and no one who collected them all would have

time left for appointments. "The information explosion is one of the

critical challenges facing physicians," says Dr. Sim Galazka of the

University of Virginia. "We've got to find ways to sort out the evidence

and apply it."

InfoRetriever grew out of a project that Dr. Mark Ebell launched from

Michigan State back in 1994. Working with several colleagues, he started

scouring 85 medical journals each month and summarizing clinically

important findings in the Journal of Family Practice. The group's reviews

and treatment recommendations still appear in the journal and in a monthly

newsletter called Evidence Based Practice. InfoRetriever includes all of

these digests, along with hundreds taken from other reliable sources, and

the whole program can be updated quarterly through Internet downloads. But

unlike Medline, a sprawling database that includes 11 million articles, IR

stays tightly focused on patient care.

Besides fielding tough questions, InfoRetriever can alert a busy

doctor to unimagined possibilities. Unlike the Physician's Desk Reference,

it includes well-documented uses for prescription drugs. It also highlights

research findings that no one is bothering to advertise. Last year, for

example, the journal Neurology published a study showing that the vitamin

riboflavin could relieve migraine headaches. "Nobody in primary care reads

Neurology", says Slawson. "Even if they did, would they remember it five

months later when a patient walks in? With InfoRetriever, you punch in

"migraine" and you get a summary of the study."

Will your intern be performing such feats the next time you show up

with a sprained ankle? Don't count on it. Ebell and his colleagues

developed InfoRetriever on their own time, without corporate support. And

though several university health systems now plan to adopt the program, no

one is marketing it directly to individual practitioners. At the moment,

only one physician in four is sure to change. "I see patients in the office

and the hospital," says Ebell. "I do house calls. I'm on call at the

hospital tonight. And the care I give depends on the information I

command." Medicine has gotten too complex to practice from a dog-eared

textbook. Fortunately, there is now an alternative. InfoRetriever and other

portable database won't make doctors obsolete. But doctors who lack them

may soon be just that.

Vocabulary to the Text.

efficient - эффективный

emergency room - пункт первой помощи

otherwise - в других отношениях

immediate - немедленный

danger - опасность

physician - врач, доктор

benefit - принести пользу/выгоду

grab - схватить

pull up - здесь: вызвать на экран

punch in - здесь: ввести

determine - определить

odds - шансы

germ - микроб

rampant - распространен

recuperate - выздоравливать

prescription - предписание

likelihood - вероятность

hasten - ускорять

recovery - выздоровление

retrieve - находить, спасать??????

enough - достаточный

palmtop - размером с ладошку

powerlful - мощный

transform - преобразовать

quantify - подсчитывать

advantage - преимущество

calculate - подсчитывать

treatment - лечение

drug - (амер.)лекарство

clarify - освещать, разъяснять

current - современный

research - научное исследование

finding - открытия

deny - отрицать

enhance - увеличивать

improve - улучшать

endeavor - попытка, старание

representative - представитель

treatment - лечение

depending on - в зависимости от

struggle - бороться

promote - продвигать, содействовать

consistent - последовательный

relevant - уместный

prove - доказать

evidenсe - свидетельство, док-во

daunting - обескураживающий

challenge - вызов, возможность

skim - просматривать

appointment - здесь: прием

explosion - взрыв

face - сталкиваться

sort out - сортировать

apply - применять

grow out of - вырасти из

launch - начинать

scour - здесь: просматривать

newsletter - информационный бюллетень

digest - краткое изложение

along with - наряду с

reliable - надежный

source - источник

update - обновлять

quarterly - ежеквартально

download - загружать

unlike - в отличие от

sprawl - здесь: разрастаться

tightly - тесно, плотно

care - забота, уход

fielding - здесь: освещение

tough - трудный (для выполнения)

alert - насторожить, сделать бдительным

reference - справочник

prescription - назначение

highlight - придавать большое значение

bother - беспокоить(ся)

relieve - облегчать

primary care - первичная помощь

punch in - войти

intern - молодой врач-стажер

perform - выполнять

feat - подвиг

sprained - растянутый

ankle - лодыжка

count on - рассчитывать на

support - поддержка

adopt - принимать/вводить

be on call - быть на вызовах

depend on - зависеть от

command - владеть

complex - сложный

dog-eared - с загнутыми углами(о страницах)

obsolete - устарелый

lack - не хватать

Comprehension Check.

Ex. Answer the following questions:

Topics to discuss.

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