المساعد الشخصي الرقمي

مشاهدة النسخة كاملة : please helpe me



Loolla
26-05-2009, 12:23 AM
السلام عليكم اخوااااااااني
أتمنى انكم بخير وعافيه
أبي اطلبكم طلب وتكفوووووون ساعدوني
ابي essay about great discoveries أي شي.. اكتشاف.. مكتشف أي شي يمشي الحال ومايكون طويل يعني ينحفظ بسرعه اختباري يوم الاربعاء وحست النت وماعرفت شسوي... بليز ياهل الطيب لا تردوني
أختكم
Loolla:small:

Loolla
26-05-2009, 09:40 PM
شدعوووووه أدخل المنتدى وماشوف ولا واحد تكرم ورد عالأقل قولوا ما نقدر ..مو فاضين لك خخخخ

قمة التحطيييييييييم اختباري بكره بس يالله ربك يعين
سلاااااام

((نونا))
29-05-2009, 04:50 AM
يالله

عاد بشري عن اختبارك ان شاءالله زين

حسام III
31-05-2009, 09:30 PM
وعليكم السلام ورحمة الله وبركاته
ممكن اني اكون تاخرت لاني اشتغل بالادب النجليزي اليوم دخلت علىمنتدى طلبات المرحلة الجامعية وشفت طلبك
هذا مقال علمي عن اككتشاف تقنية النانو انشاءالله اكون وفقت في الاختيار وافدتك حاولي تختصريه

Nanotechnology

Nanotechnology is an relatively new area of science in which extremely tiny machines, ranging from a few to a few hundred nanometers in size, are used to manipulate systems. This manipulation may take place at the cellular level or even the atomic level. A suggested name for these nanomachines is assemblers. Each assembler could function as a nanocomputer with a robotic arm. The computer could be programmed with instructions for placing atoms or molecules. The assemblers could even have the ability to replicate themselves, making production costs relatively cheap.

An example of a naturally occurring assembler is the protein-manufacturing ribosome. Ribosomes manufacture all the proteins existing in living cells and are relatively small, on the same scale as the suggested assembler. They are capable of building almost any protein. Each Ribosome does this by stringing together amino acids in a precise linear sequence. This means that it has some mechanism, such as the robotic arm of a possible assembler, to grasp a specific transfer RNA molecule and then chemically bond it to a specific amino acid by using a specific enzyme. It also uses this mechanism to manipulate the growing polypeptide, and to cause the specific amino acid to react with (and be added to) the end of the polypeptide chain creating the protein. The computer program that the ribosome follows is provided by messenger RNA, a polymer formed from four components, adenine, cytosine, guanine, and uracil. Each specific protein consists of a sequence of several hundred to a few thousand components. The ribosome receives the program from the messenger RNA and acts in a sequential fashion to build the required protein.

In the manufacturing industry, nanomachines (nanobots) might provide cheap, expendable machinery and labor. The process of manufacturing items would become more precise and efficient. Assemblers would be able to construct items atom by atom or molecule by molecule. They would be given the substances they need and would be able to use them with little waste or environmental impact. Steel could be constructed without smelting, water could be sanitized without languishing pools of sewage. Even food could be manufactured instead of grown.

Nanomachines could also have many applications in the medical field. Topical creams could carry nanobots that remove dead or decaying tissue. Saline solutions could be injected into the body with cancer-cell hunting nanobots, or hormone producing assemblers. Dental hygene could become as simple as using a nanobot-rich oral rinse used like mouth wash.

The characteristic that makes nanomachines so flexible and gives them so much potential--their size--also makes them difficult to develop and use. Communicating with nanobots inside the body could be a little tricky; although ultrasound could be used to contact nanobots, any acoustic signal it would transmit would be attenuated within a few microns of flesh. Some suggest that the nanobots should first be instructed to build a large scale transmitter at a specific location just under the skin, which the doctor could then monitor. The nanobots would have inter-nanobot communication capabilities and then could relay messages to the transmitter. In this way, the tasks of the nanobots could be changed in a sequential manner as needed.