Getting rid of banana technologies
The word "nanotechnology" – in the plural – to denote the field of research and development (see, for example, the name of the State Corporation "Russian Corporation of Nanotechnology", or The Institute for Soldier Nanotechnologies at MIT – Massachusetts Institute of Technology, USA) falls out of the traditional names of the fields of science and technology. Compare: molecular biology studies many very different processes, but nevertheless it is one science and one area of research and development, in the singular. Is it possible to turn nanotechnology into nanotechnology – a science and a field of knowledge with clearly defined goals and the subject of research?
The term as such
According to the definition from Wikipedia, nanotechnology "includes two types of devices: those that are built bottom up (from molecular components, which are then assembled according to the principle of molecular recognition), and those that are built top-down (from larger objects without control at the atomic level), having dimensions between one and a hundred nanometers". To determine the scientific and technological discipline through the possibility of building a device and its size seems inadequate to the scale of the problem stated at the same time and investments estimated in billions of dollars. It is no coincidence that the quick–witted Russian people (in this case academic) dubbed nanotechnology bananotechnologies - with a simultaneous hint of the banana republic and other aphorisms in which this fruit is mentioned.
There are undoubtedly reasons for irony: after all, nanotechnology includes a wide variety of devices and fields of knowledge. Isn't it too wide? After all, this is about the same as calling kilotechnology any devices whose mass exceeds one kilogram. At the same time, there is no doubt about the strategic prospects for civilization of creating devices whose functioning is determined on a subatomic scale. It is only necessary to formulate correctly the priorities and key problems that arise along this path.
How, apart from the size, does the nanomir differ from, for example, the microcosm?
What effects exist at the nanoscale and are absent in the microcosm?
Is it possible to combine nanoscale processes into one or more scientific and technological disciplines; and if possible, into which ones and based on which criteria?
The formulation and answers to these questions seem to be much more meaningful and constructive than the term "nanotechnology" as such.
The term "nanotechnology" has another side: the vagueness of the term itself, which does not correspond to the scientific and technological tradition, which is characterized by the desire for clarity of definitions. In fact: the term "microelectronics" meant the creation of devices that do not just work on the scale of microns (10-6 m), but those in which the movement of electrons plays a fundamental role. Cybernetics meant (roughly speaking) the creation of information transformation and processing systems. Synergetics is the analysis of nonlinear systems and structures arising in them.
Nanotechnology does not limit the field of study and creation in this way. The name speaks only about the linear dimensions of the processes that determine the functioning of devices and the properties of materials: 1 nm = 10-9 m. Recall: the classical size of atoms is 0.1 nm in order of magnitude; the lengths of valence bonds and the distances between atoms in crystal lattices of the same order; the diameter of a double–spiral DNA molecule is 2 nm; the thickness of the cell membrane is 10 nm; the size of viruses is from 20 to 300 nm. The minimum size of carbon nanotubes currently synthesized is 0.4 nm; the characteristic sizes of proteins are from 10 to 100 nanometers.
Thus, nanotechnology can include such various processes as enzymatic catalysis and quantum electronics, the creation of monoatomic films and antibiotics. Strictly speaking, any biochemical process is a nanoprocess, so the creation of almost any medicine – from vitamins and contraceptives to painkillers and serums – can be attributed to nanotechnology.
On the other hand, which area should electronics and photochemistry belong to, given that the classical radius of the key functional element of the corresponding devices, the electron r = 2.82x10–15 m (3/1000 picometres), and the Borov radius is equal to (the electron orbit closest to the nucleus in a hydrogen atom), approximately 50 picometres. So, to introduce a new scientific discipline picotechnology – which sounds no less, and maybe even more fascinating than nanotech?
The sizes of the particles that make up the nuclei of atoms, nucleons, are even smaller (for example, the classical neutron radius is 1,1x10–15, that is, approximately 1 femtometer). Well, so let's introduce an even more impressive-sounding discipline for technologies that use, for example, the creation of holes in films when they are fired by nucleons: femtotech?!
If we follow this logic, then the production of computers, shovels and stools should be attributed to kilotechnology, because each of the listed objects weighs kilograms. But this is absurd!
A device with a size of 100 nm = 0.1 micrometer (comparable in order of magnitude to the size of a medium-sized virus) should be attributed to nanotechnology or microtechnology? And if the size of the device (for example) is 101 nanometers? Where is the border? After all, it is absolutely different for different physical processes! Where is the boundary between nano- and microcosm? And does this boundary coincide with that in other nanoeffects, for example, with physical processes occurring on the surface of nanocrystals?
Taking into account all of the above, one should be extremely careful about nanotechnology as a term. And speaking of nanotechnology, it is necessary to clarify every time what exactly they mean. At the same time, there cannot be one answer for all technological applications.
It is unconstructive and insufficient to consider the size of the product as a criterion of belonging (or not belonging) to the scientific and technological discipline, as well as the method of assembling its constituent blocks.
Biology and Nanotech: do not mix!
It is quite obvious that biological processes and their use in technologies (for example, in the creation of medicines) should be separated from nanotechnology as a field of science and industry. Not because the functioning of biologically active molecules does not occur at nanoscales, but because all molecular biological processes occur at nanoscales. Biochemistry, biophysics and molecular biology are rapidly developing sciences with established terminology and do not need to redefine the name.
Nanoprocesses can be reasonably divided into:
a) those that occur not only in nano-, but also on large spatial scales, and
b) those for which the presence of nanoscale is fundamentally essential.
It seems appropriate to give a special name to processes that occur only at nanoscales. The name "nanofundamental processes" seems to be the most adequate.
In this regard, the questions seem legitimate and relevant:
1) what physical processes that can be used in the creation of nanotechnological materials and devices can exist only at nanoscale;
2) what technologies can be created on the basis of nanofundamental processes for which the spatial scale, comparable to the size of atoms and molecules, is fundamentally essential?
The answer to these questions determines the strategic directions of the development of nanotechnology, and in a broader context, the civilization of the XXI century in general.
Silicon vs. Carbon
The fact that the processes in the nanowire are divided into:
1) occurring in vivo and
2) related to inanimate nature,
defines another strategically important area of research and development.
All living things are based on carbon, while almost all modern electronics are based on silicon. In sand (SiO 2), the mass of carbon is close to 50%. The percentage of silicon in any soil on which plants grow is also high. However, despite this, the percentage of silicon in any living organism – from bacteria to humans – is absolutely negligible: as a rule, each silicon atom is controlled in vivo.
What is the reason for the "antagonism" in the living nature of carbon – and the most similar to it in properties of all the elements available in the periodic table: silicon? Perhaps this is due to the fact that both silicon and carbon form chains. But these chains are different in structure: if in carbon compounds one carbon atom is connected to another carbon atom directly, then in silicon chains, as a rule, there are atoms of other chemical elements between silicon atoms.
Recently, materials consisting of silicon chains comprising up to one hundred silicon atoms have been synthesized. However, in addition and above all, silicon is characterized by the formation of organosilicon compounds in which silicon atoms are connected in a chain with the help of oxygen atoms.
The assumption that the ability of silicon to form chains inside living organisms is dangerous for their vital activity seems to be the most natural and worthy of consideration. In any case, it is obvious that silicon, silicon as an element, is the "enemy" of the living. And the few silicon atoms that are used in vivo are under the strictest, in fact, piece-by-piece control.
Nanotech and altera vitae
As long as electronics (based on silicon) and biological processes (for which carbon is the key element) are separated, there is no problem. However, when moving to nanoscales, there is a theoretical and practical possibility of creating hybrid devices in which electronics and organics are functionally interconnected. And that's where the fundamental problems arise.
Moreover, there is a real prospect of building altera vitae, another life based either on silicon, or on silicon-carbon hybrids, or only on carbon, but based on principles different from those on which all living things are based (for example, using other amino acids or not amino acids at all, a different genetic code or in general not DNA as a carrier of hereditary information). What are the risks and prospects of alternative revolutions?
Electronics by its very nature is based on the movement of electrons. Organic processes (with the exception of relatively few, such as photosynthesis, for example) are based on the movement of atoms as a whole, as well as (for example, in enzymatic reactions) groups of atoms. The main idea of progress in electronics is to increase the frequency. Meanwhile, in vivo, the frequencies characterizing the functioning of the system, as well as the speed of movement of information carriers, are many orders of magnitude lower than in modern electronic devices. Thus, the image in the human eye is formed several tens of times per second (that is, billions of times slower than the processes that determine the speed of modern computers and TV channels), the speed of propagation of a nerve impulse is tens of meters per second (that is, millions of times slower than the speed of light with which electromagnetic vibrations propagate).
It would seem that the world of carbon is hopelessly losing to the world of silicon. It didn't happen at all! The proof of this is not only the diversity of life, but also the efficiency of the brain, which in many respects remains unattainable for modern computers.
Is it possible to convert electronics from silicon to carbon?
How dangerous is the use of carbon electronics in medicine for living organisms?
How dangerous is the use of nonlinear molecules (spherical fullerenes, dendrimers with branching structure, and others) in pharmacology and medicine?
Shouldn't computer technology be transferred from Boolean algebra to some other basic system when switching to nanoscales (recall that nothing resembling a system of zeros and ones with the transfer of values from digit to digit during addition and multiplication of numbers has been found in living organisms)?
What are the risks and prospects of alternative nanotechnology revolutions?
What are the risks of hybrid organosilicon technologies for the environment and biocenosis?
And finally, which scientific and technological disciplines and areas of industry should be formed from the range of problems currently called nanotechnology?
The formulation of these issues seems legitimate and promising both from the scientific and technological, and from the state point of view.
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What is now called nanotechnology is taking its first steps. There is a danger that (as it often happens) the availability of serious financing, state support, as well as numerous funds and corporations interested in the development of the industry around the world can make the development of this – undoubtedly strategically important for humanity – area inharmonious and even dangerous. Some – obviously secondary areas – having developed first, may interfere with the development of other, much more promising developments. Therefore, from the very beginning – today! – it is necessary to determine not only the directions that can give immediate returns. Along with the financing of certain applications, it is necessary to focus on the development strategy, designated by the generalizing term "nanotechnology", the knowledge industry and the industry.
About the author: Yuri Borisovich Magarshak – President of MathTech, Inc., Chairman of the organizing committee of the international conference Environmental and Biological Risks of Nanobiotechnology, Nanobionics and Hybrid Organic-Silicon Nanodevices (Silicon vs Carbon).
Portal "Eternal youth" www.vechnayamolodost.ru12.03.2008