Nanoparticles that Fluoresce or Act as UV Barrier.

Nanoparticles that fluoresce for a long time when light of a specific frequency is shone on them are ideal for use as markers in biology and medicine, or as security markings on valuable products as a means of identifying forgeries. Normal particles often lose their effect within a short time through the formation of hydroxides, for example, on the surface. But not those developed at the Institute for Materials Research III at the Karlsruhe Research Center. Scientists at the institute of the Competence Network NanoMat (Karlsruhe), have surrounded an oxide core with a fluorescent dye. Each of these microscopic particles is in turn enveloped in a protective polymer coating. When treated this way, the beadlike particles are non-toxic and completely insensitive to water and many other solvents. The process has been licensed to MACH-1, a company based in King of Prussia, Pennsylvania.

One of the oldest applications of nanotechnology is the use of titanium or zinc dioxide nanoparticles to protect against ultraviolet light. The product Ultramid made by BASF, a member of the Competence Network NanoChem, is employed principally to impregnate textiles. The treated fabric is as easy to wear as cotton. There is a huge demand: BASF has increased its output by 1000 percent over the last two years.

Nanotechnology offers many other remarkable means of modifying surfaces in such way that specific unwanted properties are eliminated or their functionality is improved. Carl Zeiss, for example, coats the plastic spectacle lenses of its LotuTec product line with a very fine structured film whose surface imitates the water-repellent behavior of lotus leaves. Rain forms droplets that run off the treated lenses without leaving a trace. No dirt can adhere to the surface either, making LotuTec eyewear extremely easy to clean.

Nanoparticles can also be used in antireflex coatings for spectacle lenses, display elements, car windshields and shop windows, where they have demonstrated the unexpected side-effect of improving translucency. Backed by research at the Fraunhofer Institute for Silicate Research ISC, a member of the Competence Network NanoMat, the company ALCove Surfaces in Gladbeck near Essen has developed a coating technique that increases the light transmission ratio from 92 to 99 percent. In other words, only one percent of the light is reflected. This amazing feat is achieved by studding the surface with a tightly packed array of cone-shaped nanoscale structures, which trap the light and direct it through the glass.

Задание 2. Раскройте скобки и поставьте глагол в правильную форму. Назовите время и залог глагола.

1. Nanoparticles that fluoresce for a long time … ideal for use as markers in biology (to be).

2. Normal particles often … their effect within a short time (to lose).

3. The product Ultramid made by BASF … … principally to impregnate textiles (to be employed).

4. Nanotechnology … many other remarkable means of modifying surfaces (to offer).

5. The company ALCove Surfaces in Gladbeck … … a coating technique (to have developed).

Вопросы к практическому занятию.

1. Какие наночастицы дольше всего используются для защиты от ультрафиолетовых лучей?

2. Как могут использоваться покрытия из наночастиц?

3. В каких отраслях науки могут использоваться флуоресцентные наночастицы?

4. Чем компания Карл Цейс покрывает линзы для очков линии ЛотуТек?

5. Какие побочные эффекты наблюдаются при использовании покрытий с наночастицами?

Практическое занятие 17

ФЛУОРИСЦИРУЮЩИЕ НАНОЧАСТИЦЫ В РОЛИ ФИЛЬТРОВ ДЛЯ УЛЬТРАФИОЛЕТОВЫХ ЛУЧЕЙ

NANOPARTICLES ACTING AS A UV BARRIER

Теоретическая часть

В рамках предлагаемого практического занятия студенты работают с текстом практического занятия 21. Для того чтобы они смогли построить монологическое высказывание на иностранном языке о применении покрытий с наночастицами во многих отраслях промышленности и науки. Для этого необходимо владеть следующим материалом: лексикой, предложенной в теоретической части практического занятия 21, и навыками пересказа текста.

Задания

Задание 1. Соотнесите части фраз.

security                                                leaves

valuable                                                dye

oxide                                                              light

fluorescent                                            particles

microscopic                                          products

polymer                                                lenses

shop                                                     textiles

nanoscale                                             markers

lotus                                                     structure

spectacle                                               coating

ultraviolet                                             core

impregnate                                                     window

Задание 2. Ответьте на поставленные вопросы.

1. Which nanoparticles are ideal for use as markers?

2. Why do normal particles lose their effect during a short time?

3. What is oxide core surrounded with?

4. What are special features of these beadlike particles?

5. What is one of the oldest applications of nanotechnology?

Задание 3. Перескажите текст практического занятия 21.

Вопросы к практическому занятию.

1. Для чего применяется Ультрамид?

2. Какие еще способы модифицирования поверхностей вам известны?

3. Что вы знаете о светопоглащающих покрытиях?

4. Благодаря чему было увеличено соотношение передачи света?

5. Расскажите об особенностях продукции компании Карл Цейс.

Практическое занятие 23