D라이브러리

to it?In ancient times, it was apparent that the sun and moon had an important influence on Earth. The sun supplied light and warmth by day and controlled the seasons, while the moon dimly lit the night, the phases of the moon supplied humanity with its first calendar.The sun and moon changed position relative to the stars, and the ancient Babylonians found that five bright stars(the planets ...

밝혀졌는데, 개략적 구조를 (그림5)에서 볼 수 있다. 항체는 중쇄(heavy chain) 2개와 경쇄(light chain) 2개로 된 4개의 폴리펩타이드(polypeptide)가 다이설파이드(disulfide)결합으로 연결되어 있다. 또 중쇄와 경쇄는 각각 가변(可變)부위와 불변부위로 나뉘어 있다.가변부위를 이루고 있는 아미노산의 배열은 ...

차는 것을 면하기가 어려우므로 비닐봉투 같은 것을 준비해 두는 것도 좋다. 펜라이트(pen light)에다 붉은 셀로판지(紙)를 감아 두어 광원(光源)을 약하게 하여 사용한다. 캄캄한 밤엔 펜 라이트의 빛이 의외로 자극이 커서, 눈이 자극받아 어두운 별을 볼 수 없게 되기 때문이다.또한 야외에서 앉아 ...

star, but nothing can battle its gravitation and emerge, so it's like an infinitely deep hole in space. Not even light get out, so it is a black hole. But do black holes actually exist? The centers of many galaxies give off energetic radiation in huge quantities, and the easiest way of explaining that is to suppose there are enormous black holes there. Even our own galaxy seems to have a ...

supernovas occasionally in some galaxies, even those that are very far away, because a supernova will shine with a light that may be tens of billions of times as bright as our sun. But again we have to guess at how bright the supernova actually is, and they appear only in scattered galaxies here and there. Finally, we are reduced to judging the distance of a galaxy by its total brightness ...

alike emit photons. This means we can never identify a quiet antistar or antigalaxy by simply studying the kind of light it sends us.A second type of uncharged particle is the “graviton.”Gravitons reach us in vast quantities, too, from every star and galaxy, but they carry so little energy we have so far been unable to detect them. Even if we could detect them, there are probably no such ...

종이테이프로 출력 되었다.또 다른 획기적인 일은 1950년대 후반에 개발된 라이트펜(Light pen)이었다. 즉 시간을 절약하기 위해 CRT스크린의 특정한 부분을 식별하고 또한 특정기능을 사용하는데 라이트펜이 적용되어진 것이다. 한편 설계에 있어서의 컴퓨터의 이용은 1960년대초 '이반 서더랜드'가 ...

Mirror Telescope in Arizona analyzed the light from each of these closely spaced quasars. For the first time, the light turned out to be not quite identical. There were distinct differences that indicated that the quasars were not a single object seen double, but were two separate objects.If this observation holds up, then PKS1145-071 would be the first case that has been discovered of a true ...

the work of photosynthesis in the laboratory, and doing it even faster and better. We could then turn water (puls sunlight) into hydrogen, burn the hydrogen and get water again. The fuel would never be used up; it would last as long as the sun does ...