And other suggested answers – apeiron, air, number, fire, atoms, ideas …
Unusually, the rate of polymer formation turned out to be higher at a lower temperature, but this is understandable: the determining factor for polymer formation is the rate of adsorption of monomers and oxidant, which is higher at a lower substrate temperature. It is also important that the oxidants adsorbed on the substrate contributed to the formation of not only the molecular structure of the polymer, but also the supramolecular one: doping of polythiophene with iron trichloride led to the stabilization of quinoid structures, in which a carbon-carbon double bond binds two thiophene fragments, "fixing" the parallel orientation these rings. The presence of quinoid structures in the polymer, confirmed by ultraviolet and visible spectroscopy, is an important factor contributing to an increase in the thermal conductivity of the material. Quinoid structures lengthen the conjugation system in the polymer, and also provide the parallel orientation of the polymer strands, which is necessary for the formation of π-π stacking interactions between different polymer strands. The method proposed by the researchers made it possible to obtain polythiophene films with a high degree of ordering both at the molecular and supramolecular levels. Therefore, heat transfer in them is isotropic.
The thermal conductivity of the obtained polythiophene was investigated as follows. The polymer film was applied to aluminum foil, which was then heated, and the rate of change of the polymer surface temperature was measured. The film grown at 45 ° C has a maximum thermal conductivity of 2.2 V / (K × m). For a film grown at 85 ° C, the maximum thermal conductivity, however, remains at the level of conventional polymers (about 0.25 W / (K × m)). The researchers speculate that this is because at higher temperatures, the thermal movement of the polymer segments makes it difficult to form an ordered molecular structure.
Fig. 4. Dependence of the thermal conductivity of polythiophene films on the temperature of the substrate (aluminum foil). Green dots represent film grown at 45 ° C. Its maximum thermal conductivity is 2.2 V / (K × m). Film grown at 85 ° C (red squares) has a thermal conductivity similar to that of conventional polymers. Each value is obtained by averaging twenty measurements. Drawing from the discussed article in Science Advances
Scientists plan to further study the fundamental physical processes underlying heat transfer in polymeric materials, as well as attempts to use the chemical vapor deposition method to obtain samples of other polymers with conjugated multiple bonds that can act as heat conductors. They hope that this method can be scaled up and implemented in production.
Source: Yanfei Xu, Xiaoxue Wang, Jiawei Zhou, Bai Song, Zhang Jiang, Elizabeth M. Y. Lee, Samuel Huberman, Karen K. Gleason, Gang Chen. Molecular engineered conjugated polymer with high thermal conductivity // Science Advances. 2018. DOI: 10.1126 / sciadv.aar3031.
Gennady Gorelik"Trinity Option – Science" No. 4 (323), February 23, 2021
The largest mysteries of the world history of science are three rises in scientific activity (and two extinctions), clearly separated in time and space: Greco-Roman Antiquity, the Golden Age of Islam and the New Time of the West. These riddles do not have a generally accepted solution. The historian is particularly struck by the contrast between the small social scale and the enormous significance of the rise of science. The significance, however, became apparent only in the XX century, which, according to Andrei Sakharov (and not only him), has earned the title of "century of science." And the smallness of the social scale of each takeoff is clear to anyone who wants to count its main participants: enough fingers.
I have already talked about the mystery of the birth of modern science in modern times on the pages of "TrV-Science". Let me remind you briefly. This – the third – rise differed from the previous ones not only in power, but also in its mysterious Eurocentrism. Before Copernicus, Europeans successfully mastered the achievements of the Golden Age of Islam, which, in turn, successfully mastered the ancient heritage and innovations of the East. But modern science, having originated in Europe, developed only there until the 20th century. The cultures of the three great civilizations of the East – Islamic, Indian and Chinese, with their scientific and technical traditions – turned out to be immune to the new European science, although the possibilities became much greater thanks to printing and expanding contacts. Within Europe, there were mysterious differences: by the end of the 17th century, the leadership in science passed to researchers of Protestant origin, and in the 18th century Russia, without its own scientific traditions and with general cultural backwardness, relatively easily joined world science.
This "Euro-mystery" was formulated more sharply than others by the eminent British biochemist, historian and sinologist Joseph Needham (1900-1995):
Why did modern science, with its role in the creation of advanced technology, emerge only in the West during the time of Galileo, but did not develop in China, where, until the 15th century, knowledge about nature was applied to practical needs much more effectively than in the West? 1
To answer this heuristic question historically, it can and should be clarified by narrowing it down to physics and expanding it in time and space:
What prevented ancient and medieval scientists from taking the next, after Archimedes, step in the development of science, and scientists from the Islamic world, India and China – from getting involved in the development of physics after Galileo and up to the 20th century?
The answer to this question can be seen in the unique difference between European cultures, beginning in the 16th century, when, as a result of the invention of printing and the Reformation, the availability of the main common text of Europe increased dramatically. And accordingly, the role of the main moral postulate, historically generated by the biblical worldview, has increased. We are talking about the moral self-perception of a person, about the answer to the question "Who am I?", In the formulation of Raskolnikov-Dostoevsky: "A trembling creature or a person who has an inalienable right to freedom?" Biblical anthropocentrism has provided the fundamental cognitive optimism required for modern science.
The essence of the second riddle is not so much rise as fading. In the Golden Age of Islam (VIII-XIII centuries), Arabic became the language of advanced science and philosophy, leaving us with the words algebra, algorithm, chemistry, number and others; but by the 13th century, something went wrong, and scientific thought died out. This is especially convincingly written in the book Islam and science: religious orthodoxy and the battle for rationality with a foreword by Abdus Salam, the only Nobel laureate in physics who considered himself a Muslim. According to this book, in the world of Islam, science has died out due to the fact that one understanding of this religion suppressed all others, and the very idea of the indestructible laws of Nature was declared incompatible with the omnipotence of Allah3. At the same time, the question remained about the reason for such a change in Islamic theology, but the important and opposite role of religion in riddles No. 2 and No. 3 was revealed.
And what about riddle No. 1, which occupies a very special place in the dramatic history of science?
This is the name of the general rise of Ancient Greece – socio-cultural, economic and political. They explain it by different circumstances of history with geography or by a lucky coincidence of all circumstances. None of the specific explanations has become generally accepted, and the wording “lucky coincidence”, like “coincidence”, in fact, means the absence of an explanation.
Of all the components of the Greek miracle, the birth of Western philosophy-and-science stands out – a socially very small phenomenon, but better documented than others in the surviving texts. A fundamentally new intellectual tradition arose within a very narrow historical and geographical framework, which sharpens the question of the key factors of its emergence in the 6th century BC. e., flourishing in the III century BC. e. and extinction long before the collapse of ancient civilization.
Among the significant events, two ideological breakthroughs stand out, the authors of which were Thales of Miletus, the initiator of the Greek miracle, and Euclid, who provided an example of a convincing system of accurate theoretical knowledge.
In addition to the importance of their contribution to world history, these great Greeks are united by the paucity of biographical information and the absence of ideological predecessors, which is especially intriguing4. After all, the creation of a fundamentally new is the main difference between man and other living beings.
Only the biblical God created "out of nothing" the whole Universe, and man always relies on something. If only because by the time of creativity he already has years of life behind him and a sea of impressions, both conscious and unconscious, in which clues can be hidden.
According to Aristotle, one of the greatest philosophers of Ancient Greece, who lived three centuries later than Thales and barely survived to Euclid, “even now and before, surprise prompts people to philosophize, and at first they were surprised at what directly caused bewilderment, and then, little – gradually advancing in this way further, they wondered about more significant, for example, about the change in the position of the moon, sun and stars, as well as about the origin of the universe. "
With this clue, let’s look at the beginning of the beginnings of Greek philosophy-and-science and try to figure out what could have surprised Thales and Euclid.
Historians, having searched the scientific heritage of two neighboring, much more ancient civilizations – Egyptian and Babylonian – and finding there a lot of specific knowledge useful to the Greeks, did not find any hints that could help Thales and Euclid to generate their main ideas. Which, of course, speaks of their genius, but also gives room for imagination.
I took advantage of this space, although I do not know the languages of the three ancient cultures mentioned, but I am familiar with their history only in an amateurish way: almost all my life I have been studying the history of physics of the 20th century and only in the last decade has I been carried away by the mystery of the birth of modern science.
It was natural to start with a comparison of modern science and ancient Greek, but the stumbling block – the inexplicability of the Greek miracle – got in the way. Having climbed onto this stone, I gave free rein to my imagination, relying on the experience of investigating the course of thought of physicists of the 20th century and believing that a person in his psychological essence has not changed much over the past two or three thousand years – at least, a free-thinking and inquisitive person. Otherwise, the texts created in antiquity would not say anything to the mind or heart in our enlightened time.
There are always few thinking and inquisitive people, but only they strive for knowledge of the world. According to Aristotle, true wisdom is "the science that investigates the first principles." He was not only a great philosopher, but also the first historian of philosophy. If you believe him, “the majority of the first philosophers considered only material principles to be the beginning, namely, what all things consist of, from what as the first they arise and into what as the last they, perishing, turn, and the essence, although it remains, but it changes in its manifestations. " And at the beginning of the excerpt from 1984 beginning "Thales – the founder of this kind of philosophy – argued that the beginning is water."
Thales of Miletus began a new era in the knowledge of the world with the question: "What is the arche of all that exists?" (The meaning of the Greek word ἀρχή is ‘the beginning, the first principle, the first element’.) Thales’s answer is “Water!” – even his closest followers considered unconvincing, but the question itself became the main one for the development of Greek philosophy. And other suggested answers – apeiron, air, number, fire, atoms, ideas … – are milestones on the path of thinking aimed at knowing the world. On this path, the "origin" passed from the material form to the ideal and vice versa, multiplied in quantity, until it was fixed for two thousand years in the form of four earthly elements (Fire, Air, Water, Earth) and the fifth heavenly (Quintessence, or Ether). This "dry residue" of Greek philosophy was consolidated by Aristotle, but he began the history of philosophy with Thales, and in this all historians of antiquity agree with Aristotle (at least those whose books I have read). At the same time, it is completely unknown what led Thales to his question. How did it come to him that both the stone and the flower growing next to it, from which the butterfly fluttered, and the person looking at all this, can have a certain common "beginning"?
I invented the answer to this question, relying on two observations of physicists of the 20th century, which, I believe, are also true in other centuries: 1) science is not separated from life by an impenetrable barrier; 2) among freely and deeply thinking people there are both theists and atheists.
With the former, hardly anyone will argue, but with the latter, many may disagree both among atheists and among theists. (For the sake of clarity, I call any non-atheist a theist.5) For them, I will give only two reasons.
The oldest argument is given in the Bible, where two psalms begin with the phrase: “The madman said in his heart: there is no God!” 6 Disapproval of the psalmist is understandable, of course, by his theism, but more important is the word “in his heart”, which speaks of the depth of ancient and completely unscientific atheism …
The newest argument is given by the 20th century. Physicists have always been dominated by atheists, but the great transformers of twentieth century physics — Planck, Einstein, and Bohr — recognized the importance of religious tradition. And closer to us in time and space, the completely non-ecclesiastical Sakharov expressed his credo as follows:
“I cannot imagine the Universe and human life without some kind of meaningful beginning, without a source of spiritual“ warmth ”that lies outside matter and its laws. Perhaps this feeling can be called religious. "
Those familiar with the biblical view of man and the Universe can recognize this view in the words of a humanist physicist, whose expression “I can’t imagine” sounds stronger than just “I believe”.
Thales of Miletus (620? –540 BC)
Thales of Miletus
Aristotle called the first Greek philosophers physicists (literally translating – naturalists; in the current terminology, the term "physicalist" would be more suitable), from the Greek "phisis" – ‘nature’. They looked for the answer to Thales’ question within the limits of nature, without attracting extranatural principles, supernatural forces. Hence it is clear that in the Greek miracle it is impossible to separate philosophy from science, and that philosophy-and-physics itself should be called the greatest contribution of atheism (physicalism) to the development of mankind. Even those ancient Greek philosophers, who would later be called idealists, did not need numerous Greek gods with their legendary intrigues and ungodly ugliness. From the point of view of the average ancient Greek, they were atheists.
But what could lead Thales to his strange first question?
To begin with, the founder of Greek philosophy and first in the list of the "seven wise men" of Greece was himself not entirely Greek. He came from the Phoenicians, who, before giving the world the wisest of the Greeks, invented the alphabetical writing, gave the best sailors-entrepreneurs of the Mediterranean and the best civil engineers, with whose help, according to the Bible, King Solomon built the Temple in Jerusalem.
Having inherited a craving for travel and enterprise from his ancestors, Thales went to Egypt for knowledge – and did not return empty-handed. Miletus, where Thales lived, was on the territory of present-day Turkey, and Phenicia was on the coast of present-day Lebanon. So, traveling from Miletus to Egypt and back, Thales could well visit his historical homeland – stay for a couple of days with relatives, exchange news.