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От сессии до сессии живут студенты весело...

Ключевые слова:  ФНМ МГУ, шутки

Опубликовал(а):  Гудилин Евгений Алексеевич

01 апреля 2008

STILL MANY A WONDERS TO BE DISCOVERED…

(1) WATER FUEL

A new diesel fuel, the invention made by Japanese scientists from

University of Kanagava, appears to be one of the main scientific achievements of this century. It is expected to be much more economical than the existing types of fuel, its most important advantage being environmental consciousness. The new technology is based on mixing the diesel fuel with water. Adding water to fuel normally damages fuel systems of motor-cars, so the main technical problem is to bind water using some chemical admixtures. Previous studies have shown that different emulsifying agents and stabilizers cannot be used for this purpose. Japanese scientists developed a method of emulsification of fuel with water using hydrophilic nanoparticles. The Van-der-Vaals forces play the main role in emulsification. The new method is much easier and cheaper than the others. Industrial water can be used without purifying, which substantially reduces the cost of the fuel, and the emulsion is very stable. Water evaporation in the engine causes the fuel dispersion and increases the efficiency of its burning. At the same time the burnout temperature decreases, nitrogen dioxide emission being reduced as well. The new diesel fuel has been tested on 30-tonned truck. The decrease of fuel consumption and harmful substance emission was about 50% and 70% respectively. The tested fuel was formed of 50% of water and 50% of diesel fuel. The new fuel is considered to become environmental pride, for it can help solve at least one of the main ecological challenges facing mankind.

(2) SOOTHING A-BOMB

The Earth can be easily destroyed with lots of nuclear charges so a significant part of scientists' effort is aimed to prevent the effects of this kind of attack. It is true that radioactivity is the most damaging factor of A-bomb. So if the radiation effect will be avoided it will help us to survive. According to the theory of electromagnetism X-rays or gamma rays are electromagnetic waves, so they can be concentrated by devices working like ordinary optical lenses. The principal problem of concentrating these waves is their low response to various influences, mainly because of such characteristics as frequency, speed and high energy per particle. A new device which was successfully tested by an international group of scientist in New Mexico is an electromagnetic field generator arranged like a giant hoop. The "hoop" concentrates high-frequency rays in a small point on a many-layered material that generates an electrical current and accumulates the energy cell. It is evident that most of gamma rays will penetrate the material, but in fact it will be absolutely safe for humans because of very small cross section of radiation. The new invention developed as a "Redeemer of the World" is believed to be useful in many ways, in the first place as a particle accelerator or spacecraft defence installation.

(3) BIOMATERIALS FOR YOUR HEALTH

The greatest discovery has been made recently in Moscow State University, Russia. One of the major problems of so-called biomaterials seems to have been solved by Russian researchers Alex I. Pultyaev and Valery H. Revesov. It is generally known that biomaterials are needed for making bone-implants. The structure of such materials is supposed to be similar to the inorganic component of a bone — Hap (hydroxylapatite). These bone-implants are based on calcium phosphates — Hap, DCPD (dicalcium phosphate), TCP (α-, β-tricalcium phosphate), CPP (calcium pyrophosphate) and the like. Different complex methods of making such implants existing have been considered so far to be both time-consuming and obsolete. It is commonly recognized that α-TCP can only be used for preparing HAP as an individual component. It must be admitted that α-TCP is characterized by phase instability (α-TCP is a high-temperature phase and it turns into a stable phase β-TCP lower the temperature of 1100̊C). As a result this very substance can be received only with hard firing some supplementary conditions being used. In order to stabilize the high-temperature phase a special mix was made. It consists of several normally used precursors: CPP and carbonate calcium the last component being arsenic oxide (mass fraction – 2%, no more). The latter is used to prevent phase transformation. TCAs (Ca3(AsO4)2) is believed to be isostructural to α-TCP, so substances like silicon, vanadic oxides can be regarded as other stabilizing fins. Then the mixes of TCP stabilized by arsenic oxide and different liquids (water, the solution of sodium citrate, ethanol, silica gel) were made. After high-pressure molding and hydrolysis (during 3 days, the temperature of hydrolysis was 60̊C) the mechanical and biocompatibility tests were made. All in all the number of synthesis stages was not increased. As a result the compression resistance of materials made using the solution of sodium citrate is the biggest one its coincidence with the same parameter of the bone being more than impressive. Moreover dopes of citrate acid and arsenic conduce to quicker bone overgrowing. It should be mentioned that arsenical necrosis is the consequence of high concentration of arsenate in the organism. According to the Fathers of Medicine the difference between medicine and poisonous effects is in the dose only. Valery H. Revesov said that visual and even internal differences between bones of a healthy man and a patient with such an implant will be impossible to detect in 6 months after the operation.

(4) PERSEUS’S HELMET OF INVISIBILITY – AN UPGRADED VERSION?

A magnificent invention has recently been made in Moscow State University. A substance making an object it covers invisible was announced to have been created. Although it is known that “inviselaser” includes Si-contained polymers doping with Fe and Co its proper structure hasn’t been discovered yet. Admittedly, metal ions and molecules of polymer forced by electromagnetic interactions make а micelle-like structure. There are ions accommodating under the surface of material along with long non-polar molecules of polymer (“tails”) associated with the ions inside. The unique optical properties of “inviselaser” can be explained by the highest light-reflecting ability of this material caused by virtual absence of light diffraction. Inviselaser is isolated from the dilute water solutions of Si-contained polymers. The solution must be held for 1 hour keeping up the temperature at about 80 °C to reach the needed conformation of polymer clews. Acetates of Fe and Co are used as the sources of these ions in the solution. They ought to be added into the solution at the very end of the process in order not to let the metal ions penetrate the polymer clews as the highest values of light-refraction coefficient are detected when the concentration of ions accommodated under the polymer clews reaches its maximum. Crystallization is the next stage of the synthesis. Because of using liquid nitrogen crystallization speed is high. The biggest challenge lays in the selection of the proper metal ions concentration. According to image analysis of material surface the slightest deviation of ions concentration causes structural differences at the microlevel of inviselaser. Another big problem is associated with the choice of Co and Fe ions per sent ratio. The best results were shown by the material with Fe/Co=2/3, but taking a small step aside will inevitably annihilate all the signs of its magnificent properties. Which is now impossible to explain.

(5) TELL ME WHAT YOU THINK OF AND I’LL TELL YOU WHAT YOU ARE

In 2005 a large number of experiments were carried through by the scientists of the USA. It was proved that a person’s throat sides throb during the process of thinking. A new device, allowing reading somebody’s mind, was invented on the base of this fact and tested repeatedly. Originally it has been struck out to know what suspects and witnesses think about in court. The invention looks like a small walkman with earphones. Its main active part is а delicate detector which, using special locators, catches minute oscillations of air promoted by throat sides. The closer the examined person to the device is, the better the signal is heard. These high frequency oscillations are transduced and enhanced in order to gain audio frequency signals, resulting in possibility to discern speech. Due to the fact that frequencies of emitted oscillations vary in a narrow range, the device is able to discriminate between desirable target signals and hum. Although the range is narrow, each person is, nevertheless, characterized by their own frequency of throat oscillations, determined by individual distinctions of throat constitution. So it is in our ability to tune for a frequency of a particular person, pushing a button on the device cabinet. Accordingly, only people, who know anatomy well, can use this device efficiently.

(6) A NEW OXIDE OF Ti.

A new oxide of Ti was received in Moscow State University few days ago. The reduced Ruddlesden-Popper phases, Sr3Ti2O6+δ with δ=0.91, 0.64 and 0.38, have been prepared in a nitrogen atmosphere. The crystal structures were determined by powder neutron diffraction and by Rietveld refinement using X-ray powder diffraction data. The results have shown that the oxides received have the structure of the Ruddlesden-Popper gomolog type with perovskite blocks containing two layers of corner-linked TiO6, octahedral. Oxygen vacancies are found both in O(3) and O(4) sites but the majority are along one crystallographic axis in the TiO2 plane, inducing an orthorhombic distortion of the normally tetragonal n=2 Ruddelsden-Popper structure. Superstructures due to oxygen ordering are observed by electron microscopy. The magnetic measurements reveal complex behavior with some ferromagnetic interactions present for Sr3Ti2O6.91 and Sr3Ti2O6.64. TG tracing, acquired from a heating/cooling cycle of the powder milled for 11 days, displayed three weight-loss steps: 2 wt % between room temperature and 300 C, 0.6 wt % from 300 to 680 C, and 3 wt % between 680 and 910 C. The DTA curve exhibits only one endothermic peak on heating to 835 C, corresponding to the important last weight-loss step. The TG and DTA recordings were interpreted on the basis of XRD data taken at increasing temperatures. There were no noticeable changes up to 250 C; however, SrCO3 diffraction lines clearly appeared at temperatures above 500 C and remained unaltered up to 700 C. Beyond 800 C, the doublet at 231, characteristic of Sr2[Srn-1TinO3n+1] RP oxides, started to become visible, but its relative intensity showed that the formation of Sr3Ti2O7 had not been completed. Moreover, traces of Sr2TiO4 and SrTiO3 were still observed at the final room temperature.

(7) TO DWARF OR NOT TO DWARF?

Using LiCoO2 as a cathode material for secondary Li batteries is a well-known fact. Li can be reversibly removed from and reinserted into LiCoO2. The layered form of LiCoO2 is ideally suited to accommodate large changes in Li concentration. British scientists made a breakthrough invention a week ago. Lots of smart tiny dwarfs were found in the structure of LiCoO2. The creatures seem to be really intelligent being able to calculate extremely fast the amount of the Li-ions that should be transported to make the battery work more productively. They dwell in small houses on the Co-ions and all of them are fans of the active sports because doing sport every day makes them stronger and dwarfs can transport more ions in a time. Russian scientists supported by their British colleges are trying to make the useful dwarfs live in the structure of the LiNiO2 to make these batteries be more productive as well. Sad to say, they are having problems. Most of the age-challenged, intelligent and strong dwarfs are loath to move. The solution of the problem can be found in the young, who are interested in finding some new places to settle.

(8) A NANOGARDEN-VARIETY SYMTHESIS

One class of nanoscale materials which has attracted great attention is the quasi-one-dimensional (Q1D) system, since the revolutionary discovery of carbon nanotubes in 1991. Enormous progress has been achieved in the synthesis, characterization, and device application of the Q1D systems. A variety of inorganic nanomaterials, including single element and compound semiconductors, have been successfully synthesized. With their unique physical property characterizations, they are promising candidates for future nanoscale electronic, optoelectronic and sensing device applications. The aim of this work was synthesis of SnO2 nanowires. SnO2 is wide band gap semiconductor oxide. SnO nanopowders and nanowires are used as a sensitive element of gas sensors. The unique nanostructure was synthesized in our laboratory – we called it ‘nanogarden’. We used the method of thermal evaporation with SnO precursor. The crucible with the precursors was placed in the hottest temperature zone of horizontal tube furnace. Thermal evaporation is the most widely used method of synthesis nanowires of metal oxides. As was shown by SEM, the product consists of Q1D ‘nanostalks’ with some nanoflowers and nanoleaves, growing from some places of those ‘nanostalks’. There were also nanofruits, nanoberries and other interesting nanostructures. It was amazing because without magnification the products looked like white crystal powder with some cotton-wool admixtures. The products were analyzed with XRD. The only phase found was SnO2 rutile, with the prevalent c-axis crystallographic orientation. We were very surprised to watch all this beauty in the nano-level. Some beautiful novelties can decorate our scientific life!

(9) ROBOTS WILL PLAY CUP-FINAL

A lot of scientists all over the world are known to be interested nowadays in machines which behave in a human-like manner, performing difficult or repetitive tasks. Today a lot of different kinds of robots have been invented. For example, as for scientific information work, robots are good at exploring the oceans. They don’t need air and can bear deep water pressure that would crush a human diver. Some of them are little submarines; others are attached to a ship and controlled by a human. Robots are also ideal for inspecting oil fields. Domestic robots work in ordinary homes. Some do only one repetitive job, such as mowing the lawn or vacuuming floors. Others can speak and call the police or relatives if something goes wrong in the house. This makes them useful for elderly people. The novelty that is reported here will please football fans while football players will possibly be discouraged (because the robots could be taken to football’s World Cup). It is an international project to develop robots with the skills needed to play football. There is still a long way to go. Today little robots built from construction materials can get possession of the ball but only kick it into a goal defended by a single opponent.

(10) THE LOGHT THAT WORKS

A fascinating invention in the area of semiconductor materials has been made recently. An electric torch that works on solar batteries is the very thing that many travelers and explorers have been longing of. Modern technologies make this possible. The main advantage of this device is that it needs no storage battery. Absence of accumulators followed to significant weight decrease of the torch that is indispensable under certain circumstances. Light is powered by solar batteries that are presented by multiple silicon bars, located everywhere on the surface of the torch. Multiple industrial applications of this invention are already expected to be found. It is evident that the brighter the sun shines the more light is emitted by the torch. One can use it wherever they like without worrying that the batteries will suddenly run down. Imagine your keys fall down into a gap between rocks while you are climbing a mountain. Unless it is dark, the new device will help you to illuminate the shadowed place between rocks and to find the keys. The only disadvantage of the invention is that the torch won’t work in absolute darkness. This seems a minor imperfection, however, since the occasions, when one has to use light in total obscurity, are rare.

(11) THE LIGHT THAT WORKS – 2

Searching new materials for lithium batteries is among recent topical issues. The main problems in this research area are numerous requirements to a potential material. It should have high lithium capacity and stability, along with low price and toxicity. This year a new phase of manganese nanotubes with phenomenal properties has been discovered by scientists from Moscow State University. The batteries based on this material don’t need charge! The crux of their work is that manganese in battery exchange electrons with oxygen and nitrogen from atmosphere. At the cost of ion interaction the current appears. Capacity of this material increases with the lapse of time. So the new era of alternative energy is near.

(12) SEMICONDUCTORS FROM VEGETABLES. COMING SOON

Sprout has many exceptional electronic properties as recent studies have shown. Realizing the full potential of sprouts in electronic systems requires a scalable approach to device and circuit integration. Calculations show that sprouts-based semiconductors enable good device-level performance and device to device uniformity. Such composites can be formed using materials that nature kindly gives us each year. The results of the experiments may represent the rout to large-scale sprouts electronic. Fundamental studies have shown that sprouts can be formed via different techniques – breeding in greenhouses or just outdoors. Theoretical work has examined that semiconductors synthesized in greenhouses have better output voltage and are more static while used. Nowadays experimental results are lacking because of some problems connected with conducting properties extinction during cooking. Handling the problem of synthesizing such materials we can see some limitations endorsed on houseware. Fundamental studies are being provided now worldwide.

(13) SIMPLE BUT EFFECTIVE

Phosphor materials find wide applications ranging from fluorescent lamp to luminescence immunoassay. They are generally crystalline in nature (deeply under the ground). Our investigation is focused on phosphor materials used in lamps which can illuminate without any electricity. Lamp phosphors are mostly red in color. The fluorescent lamps are coated with phosphor by using a suspension of phosphor powder particles. Preparation of single phase compound is difficult by the conventional state method so wet-chemical methods and combustion method were also used. The preparation of yttria is using yttrium nitrate and oxalyl dihidrazide are dissolved in a minimum amount of water in a pyrex dish. Then “abrah-kadabrah” must be said three times and pyrex dish located into a muffle furnace maintained at 400C. In 5 hours our powder is ready. Conclusions. Rare earth lamp phosphors were obtained by a very simple way. All powders are single phase and ready for using. That is a great achievement because now the humanity has a course of red light without using rare natural recourses and other types of energy.

(14) GADJET BAG

We are in desperate need of a new gadget bag. We are all looking for something that is small enough that we can carry it all the time, but big enough that we can fit iPod, cell phone, a couple of books, a small camera, pens, cosmetics and lots and lots of first priority things. The major emphasis of this paper is to make such bags using different types of basalt fibers. The primary reason for using basalt fibers instead of thread to sew bags is that basalt possesses good chemical and physical qualities. It is evident that if you need strong and bright materials, you will get it using materials made of basalt fiber. The most tremendous thing is that when people put many books and different stuff inside this bag it will not get bigger in size. More than that, it will not be even heavier no matter how much you will stuff into it. Isn’t this a great idea? It is important to know that you can make such bags using only basalt which is well known as rock found in virtually every country around the world. Although the basalt fibers proved to be quite brittle, test results represent that an appropriate choice of fiber volume and length can noticeably increase toughness. However, it is not commonly known that basalt can be used in manufacturing and made into fine, superfine and ultra fine fibers. In other words, basalt continuous fibers offer the prospect of a completely new range of composite materials and products. Recent experimental studies have shown that basalt products have no toxic reaction with air or water, are non-combustible and explosion proof. We observe that in contact with other chemicals they produce no chemical reactions that may damage health or the environment.

(15) TEA INFLUENCES YOUR LIFESPAN

Several months ago a group of Japanese scientists which was working on the properties of the different kinds of tea revealed the most significant one. Numerous clinical experiments proved that different kinds of tea can enlarge or reduce human lifespan. A huge complex of different chemical substances was found in fresh tea leaves. After that, scientists treated the leaves using different methods, especially those applied from the archaic periods of civilization to make the famous drink. It was found out that drying and frying of tea leaves as it is normally made to produce “black” tea leaves only a small rate of the substances lately uncovered. The obtained data explain the fact that people living at the western hemisphere haven’t noticed the fact yet. The statistics shows that it is “black” tea they generally drink. For the eastern hemisphere’s inhabitants, drinking “green” tea is more common (“green” tea is a kind of tea whose leaves haven’t been treated by high temperature), that is why eastern scientists were the first to turn to the phenomenon. As for the different effects of reducing and enlarging, the research made on the assays of leaves from different regions allowed graduating the tea sorts from different countries to the influence they have over human lifespan. However, the reasons of that difference haven’t been investigated yet. This invention could explain some historical facts that were considered to be incomprehensible, for example, the amazing longevity of Chinese sages or the superhuman rapidity of reactions that is demonstrated by samurais. It could be supposed that samurais used only special kinds of tea which brought them rapid reactions in exchange for some part of lifespan; the relative movement of their time speeded up with the acceleration of their metabolism. The next step that the team of scientists would take is the appeal to international health authorities with the demand to mark all the teas which come into the world market with the effect they make on the human’s lifespan (for example, “«Fine Darjeeling, -23% ^_^»”).

(16) TRAPPING THE LIGHT FANTASTIC

Research into metamaterials has given rise to such fantastic notions as better-than-diffraction-limit lenses and invisibility cloaks. But when married with the principles of slow light propagation, metamaterials – materials with regular structure on the same length scales as radiation propagating through them – can also stop a rainbow in its tracks. A new theoretical study by researchers at some universities in the UK proposes that a metamaterial structure can stop various frequencies of light altogether at different points: a trapped rainbow. The trick to the process is to exploit a phenomenon, in which polarized light encountering an interface between two media – in this case, the interface between normal and negative refractive index materials – can travel along the interface. A suitably designed interface can even force light to travel backwards. Before coming to a halt, the light effectively takes three steps forward and two steps backward while becoming slower and slower. At the critical width of the tapered layer the light is trapped. Such trapped light represents a great advance toward optical computing, which has until now been held back by the difficult nature of taming photons. The impressive advances in the nanotechnologies have and are providing a very fertile ground for the actual realization of the very proposed idea. The main challenge is to overcome inherent losses in metamaterials.


Источник: Нанометр



Комментарии
Semenenko Dmitry Alexandrovich, 02 апреля 2008 00:41 
Наша всеми любимая госпожа Сурганова (преподаватель английского на ФНМ) просила выбрать номинантов в следующих категориях:
1. The funniest one
2. The most incredible one
3. The most ‘scientific’ one
4. The most credible one
5. The most ‘april’ one ( both stylistically smart and inventive)
И сколько будет голосов?
Некоторые мило, но в целом слишком много букв...
Марихин Николай, 02 апреля 2008 12:38 
А вот в нашем подмосковном ВУЗе, затерявшемся в лесах Подмосковья, на 1-е апреля клали манекен на Савёловскую железную дорогу. По-моему и смешно, и английского не надо знать. Машинисты были в восторге, улыбались с ленинской хитринкой
Палии Наталия, 02 апреля 2008 13:57 
Интересно, а эту заметку: Cleaning fabrics with light, восприняли бы за Первоапрельскую шутку, и в какой категории ее можно было бы номинировать (?)
Палии Наталия, 02 апреля 2008 14:51 
Номинанты в категориях (на мой взгляд):
(5) 1. The funniest one
(1) 2. The most incredible one
(15) 3. The most ‘scientific’ one
(8) 4. The most credible one
(7) 5. The most ‘april’ one ( both stylistically smart and inventive)
На "А вот в нашем подмосковном ВУЗе, затерявшемся в лесах Подмосковья, на 1-е апреля клали манекен на Савёловскую железную дорогу. По-моему и смешно, и английского не надо знать. Машинисты были в восторге, улыбались с ленинской хитринкой" - физтехи красили рельсы в черный цвет. Но это не шутки, а вандализм...
Акбашев Андрей Рамирович, 12 апреля 2008 19:57 
(16) the funniest one
(4) the most incredible one
(12) the most "scientific" one
(9) the most credible one
(15) the most 'april' one

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