eBooks de Historia de la ciencia, página 10 de 61

La nozione di orientabilita di una superficie, quale fisiologica generalizzazione dellorientabilita di una curva, viene affrontato in questo ebook utilizzando i metodi della geometria differenziale. Vengono presi in considerazione "casi patologici" come il nastro di Mobius e la bottiglia di Klein, passando per le "singolarita di Van Hove", di estrema importanza nella fisica dello stato condensato.Marcello Colozzo, laureato in Fisica si occupa sin dal 2008 di didattica online di Matematica e Fisica attraverso il sito web Extra Byte dove vengono eseguite "simulazioni" nellambiente di calcolo Mathematica. Negli ultimi anni ha pubblicato vari articoli di fisica matematica e collabora con la rivista Elettronica Open Source. Appassionato lettore di narrativa cyberpunk, ha provato ad eseguire una transizione verso lo stato di "scrittore cyber", pubblicando varie antologie di racconti.

Industrial Applications of Soil Microbes is a compilation of reviews on the industrial usage of soil microorganisms. Readers will be updated about recent applications of soil bacteria, fungi and viruses in sectors such as agriculture, biotechnology, environmental management. Volume 4 includes review on mycorrhizal fungi, endophytes and a range of microbial chemicals and processes beneficuall at industrial scale. The 19 chapters start with an overview of mycorrhizae as biofertilizers, their symbiosis with plants, and their applications in improving crop yield, stress management, and soil health. Case studies on Lycopersicon esculentum highlight practical benefits. Soil microbes, endophytes, and microbial proteases are discussed for their role in biocontrol, disease management, and crop improvement. The volume also explores eco-friendly nematicides, viruses in temperate fruit crops, mushrooms nutritional value, and metagenomics for bioinoculants. Overall, the volume emphasizes sustainable practices and future prospects involving microbes and microbe-assisted processes. Readership General readers, microbiology and biotechnology enthusiasts, science students and industrial trainees

Fur Pflanzenfreunde und Naturliebhaber: Der Schnabelhut ist mehr als eine botanische Raritat - er ist ein faszinierendes Naturwunder aus dem Amazonas, das Wissenschaft und Mythologie auf einzigartige Weise vereint. Dieses Buch ladt Sie ein, die Geheimnisse dieser besonderen Pflanze zu entdecken, deren Blutenstaub eine sanfte Wirkung auf die Sinne entfaltet und in den spirituellen Ritualen des indigenen Volkes der Karara eine zentrale Rolle spielt.Erleben Sie die tiefe Verbundenheit der Karara zur Natur und erfahren Sie, wie der Schnabelhut als Symbol fur die Harmonie zwischen Mensch und Umwelt steht. Ob als faszinierender Blick auf die Ethnobotanik oder als Inspiration fur das eigene grune Zuhause - diese Reise in die Welt des Schnabelhuts wird Sie mit einem neuen Verstandnis fur die Kraft und das Geheimnis der Pflanzenwelt erfullen.

Landamento del caldo e freddo umido nel capoluogo felsineo e le sue implicazioni sanitarie

A few lines will suffice to explain why we have compiled the present volume, to what wants it responds, and what its sphere of usefulness may possibly embrace.In our teaching of plastic anatomy, especially at the Ecole des Beaux-Artswhere, for the past nine years, we have had the very great honour of supplementing the teaching of our distinguished master, Mathias Duval, after having been prosector for his course of lectures since 1881it is our practice to give, as a complement to the study of human anatomy, a certain number of lessons on the anatomy of those animals which artists might be called on to represent.Now, we were given to understand that the subject treated in our lectures interested our hearers, so much so that we were not surprised to learn that a certain number repeatedly expressed a desire to see these lectures united in book form.Edouard CuyerGENERALITIES OF COMPARATIVE ANATOMYOf the animals by which we are surrounded, there are some which, occupying a place in our lives by reason of their natural endowments, are frequently represented in the works of artistseither as accompanying man in his work or in his amusements, or as intended to occupy the whole interest of the composition.The necessity of knowing, from an artistic point of view, the structure of the human body makes clear the importance we attach, from the same point of view, to the study of the anatomy of animalsthat is, the study of comparative anatomy. The name employed to designate this branch of anatomy shows that the object of this science is the study of the relative position and form which each region presents in all organized beings, taking for comparison the corresponding regions in man. The head in animals compared with the human head; the trunk and limbs compared to the trunk and limbs of the human beingthis is the analysis we undertake, and the plan of the subject we are about to commence.Our intention being, as we have just said, the comparison of the structure of animals with that of man, should we describe the anatomy of the human being in the pages which follow? We do not think so. Plastic human anatomy having been previously studied in special works, we take it for granted that these have been studied before undertaking the subject of comparative anatomy. We will therefore not occupy time with the elementary facts relative to the skeleton and the superficial layer of muscles. We will not dilate on the division of the bones into long, short, large, single, paired, etc. All these preliminary elements we shall suppose to have been already studied.This being granted, it is, nevertheless, necessary to take a rapid birds-eye view of organized beings, and to recall the terms used in their classification.Animals are primarily classed in great divisions, based on the general characters which differentiate them most. These divisions, or branches, allow of their being so grouped that in each of them we find united the individuals whose general structure is uniform; and under the name of vertebrates are included man and the animals with which our studies will be occupied. The vertebrates, as the name indicates, are recognised by the presence of an interior skeleton formed by a central axis, the vertebral column, round which the other parts of the skeleton are arranged.The vertebrate branch is divided into classes: fishes, amphibians or batrachians, reptiles, birds, and mammals.

Die Kosmologie befindet sich zur Zeit in einer Krise. Die Welt ist homogen und isotrop, also uberall gleich. Unser beobachtbarer Kosmos ist fur jeden Beobachter ein raumlich, zeitlich und energetisch begrenzter kugelformiger Ausschnitt des unendlichen Universums. Jeder Beobachter befindet sich immer im Zentrum seines beobachtbaren Teils des Universums. Er ist in seinem Kosmos. Es gibt also so viele Kosmen wie Beobachter im Universum. Wir Menschen auf der Erde sehen nur alle dasselbe (unseren Kosmos), weil wir und unser Ausgangspunkt im Vergleich zu den kosmischen Raumdimensionen so extrem klein sind. Ein beobachtbarer Kosmos kann mathematisch mit den drei Koordinaten (Raum, Zeit und Energie) als Einheitskugel mit relativen Koordinaten im unendlichen Universum beschrieben werden. Jede relative Koordinate hat dann eine untere und eine obere Grenze von (0 bis 1). Jedes Phanomen hat einen zeitlichen Anfang und muss auch ein zeitliches Ende haben. Die zeitliche Anderung innerhalb eines Zeitintervalls (Dauer) und der relativistische Energie-Impuls-Erhaltungssatz sind die Konstanten. Aus dem kleinsten Planckschen Wirkungsquantum h und der neuen kosmischen Zeitkonstanten T ergibt sich eine weitere Feinstruktur, die die Quantentheorie um viele Groenordnungen an Kleinheit ubertrifft.

"Comment se forment et évoluent les galaxies? Pour tenter de répondre à cette interrogation, jai développé un nouveau concept dinstrument pour analyser la lumières des astres. Cette invention a donné

Un Monde Sans Plastique : Des Solutions dAvenirLe plastique, autrefois symbole de progrès, est aujourdhui lun des plus grands défis environnementaux. "Un Monde Sans Plastique : Des Solutions dAvenir"

Niels Bohr (18851962) was a Danish physicist who played a key role in the development of atomic theory and quantum mechanics, he was awarded the Nobel Prize for Physics in 1922. First published in 1924, this second edition of a 1922 original contains three essays by Bohr dealing with the application of quantum theory to problems of atomic structure: the first essay is on the spectrum of hydrogen; the second is on the series spectra of the elements; the third is on the structure of the atom and the physical and chemical properties of the elements. The essays do not aim at a comprehensive treatment of their subjects, instead providing the reader with a more accessible, generalised viewpoint. This book will be of value to anyone with an interest in Bohrs contribution to physics.

« Le plateau central et ses volcans un Etna français » de Stanislas Meunier et Philippe Glangeaud est un ouvrage captivant qui plonge le lecteur au coeur de la géologie fascinante du Massif Central.

Neste momento crucial, em que a intersecção entre ciência, tecnologia e sociedade molda nosso futuro, Luiz Ricardo Mantovani da Silva nos oferece uma obra indispensável, com um olhar aguçado e a prof

Part of the ensuing Discourse about Light was written at the Desire of some Gentlemen of the Royal-Society, in the Year 1675, and then sent to their Secretary, and read at their Meetings, and the rest was added about twelve Years after to complete the Theory; except the third Book, and the last Proposition of the Second, which were since put together out of scatterd Papers. To avoid being engaged in Disputes about these Matters, I have hitherto delayed the printing, and should still have delayed it, had not the Importunity of Friends prevailed upon me. If any other Papers writ on this Subject are got out of my Hands they are imperfect, and were perhaps written before I had tried all the Experiments here set down, and fully satisfied my self about the Laws of Refractions and Composition of Colours. I have here publishd what I think proper to come abroad, wishing that it may not be translated into another Language without my Consent.The Crowns of Colours, which sometimes appear about the Sun and Moon, I have endeavoured to give an Account of; but for want of sufficient Observations leave that Matter to be farther examined. The Subject of the Third Book I have also left imperfect, not having tried all the Experiments which I intended when I was about these Matters, nor repeated some of those which I did try, until I had satisfied my self about all their Circumstances. To communicate what I have tried, and leave the rest to others for farther Enquiry, is all my Design in publishing these Papers.In a Letter written to Mr. Leibnitz in the year 1679, and published by Dr. Wallis, I mentiond a Method by which I had found some general Theorems about squaring Curvilinear Figures, or comparing them with the Conic Sections, or other the simplest Figures with which they may be compared. And some Years ago I lent out a Manuscript containing such Theorems, and having since met with some Things copied out of it, I have on this Occasion made it publick, prefixing to it an Introduction, and subjoining a Scholium concerning that Method. And I have joined with it another small Tract concerning the Curvilinear Figures of the Second Kind, which was also written many Years ago, and made known to some Friends, who have solicited the making it publick.In this Second Edition of these Opticks I have omitted the Mathematical Tracts publishd at the End of the former Edition, as not belonging to the Subject. And at the End of the Third Book I have added some Questions. And to shew that I do not take Gravity for an essential Property of Bodies, I have added one Question concerning its Cause, chusing to propose it by way of a Question, because I am not yet satisfied about it for want of Experiments.This new Edition of Sir Isaac Newtons Opticks is carefully printed from the Third Edition, as it was corrected by the Authors own Hand, and left before his Death with the Bookseller. Since Sir Isaacs Lectiones Optic, which he publickly read in the University of Cambridge in the Years 1669, 1670, and 1671, are lately printed, it has been thought proper to make at the bottom of the Pages several Citations from thence, where may be found the Demonstrations, which the Author omitted in these Opticks.

IN connexion with the discussion of the physical interpretation of the quantum theoretical methods developed during recent years, I should like to make the following general remarks regarding the principles underlying the description of atomic phenomena, which I hope may help to harmonise the different views, apparently so divergent, concerning this subject.The content of this paper is essentially the same as that of a lecture on the present state of the quantum theory delivered on Sept. 16, 1927, at the Volta celebration in Como. For a summary of the theory just previous to the development of the new methods the reader is referred to a lecture of the author, Atomic Theory and Mechanics, published in this periodical (NATURE, 116, 809; 1925).The rapid development which has taken place since has given rise to a considerable number of publications. The present paper is confined to a few references to recent articles which have a special bearing on the subject now under discussion.

IN a series of papers in this periodical the present writer has attempted to give the outlines of a theory of the constitution of atoms and molecules by help of a certain application of the Quantum theory of radiation to the theory of the nucleus atom. As the theory has been made a subject of criticism, and as experimental evidence of importance bearing on these questions has been obtained in the meantime, an attempt will be made in this paper to consider some points more closely.

Niels Bohrs atomic theory of 1913 is one of the absolute highlights in the history of modern science. It was only with this work that physicists realized that quantum theory is an essential ingredient in atomic physics, and it was also only with this work that Rutherfords nuclear model dating from 1911 was transformed into a proper theory of atomic structure. In a longer perspective, Bohrs quantum atom of 1913 gave rise to the later Heisenberg-Schrodinger quantum mechanics and all its marvellous consequences. This book is a detailed account of the origin of the Bohr atom centred around his original scientific articles of 1913 which are here reproduced and provided with the necessary historical background. In addition to the so-called trilogy the three papers published in Philosophical Magazine also two other and less well-known yet important papers are included.The present work proceeds with a chapter outlining earlier ideas of atomic structure and tracing Bohrs route from his doctoral dissertation in 1911 over his stays in Cambridge and Manchester to the submission in April 1913 of the first part of the trilogy. The reproduction of Bohrs five articles is followed by notes and comments directly related to the texts, with the aim of clarifying some of the textual passages and to explicate names and subjects that may not be clear or well known. The reception of Bohrs radically new theory by contemporary physicists and chemists is discussed in a final chapter, which deals with the immediate reactions to Bohrs theory 1913-1915 mostly among British, German and American scientists.Historians of science have long been occupied with Bohrs atomic theory, which was the subject of careful studies in connection with its centenary in 2013. The present work offers an extensive source-based account of the original theory aimed at a non-specialist audience with an interest in the history of physics and the origin of the quantum world. In 1922 Bohr was awarded the Nobel Prize for his theory. The coming centenary will undoubtedly cause an increased interest in how he arrived at his revolutionary picture of the constitution of atoms and molecules.

Em Estrada para lugar nenhum , o jornalista, podcaster e crítico Paris Marx desafia as visões utópicas do Vale do Silício sobre o futuro do transporte. Desvendando as falhas nas promessas de carros a

Nel terzo volume della collana I manuali dellaspirante scienziato viene fornita una guida per orientarsi nel complesso mondo della gestione dei rifiuti alla luce delle recenti disposizioni riguardanti leconomia circolare.Paradossalmente la gestione dei rifiuti, importantissima nellottica della tutela dellambiente e del pianeta, e contemporaneamente uno degli argomenti che piu appassionano riflessioni, in particolare quelle socio-politiche e, nello stesso tempo, un tema nel quale la discussione di massa e caratterizzata da grande approssimazione, forte inconsapevolezza e, troppo spesso, solamente da affermazioni ideologiche e/o demagogiche destituite di alcun fondamento tecnico-scientifico.In questo manuale, lautore riesce a condensare, in poche pagine, molte delle conoscenze indispensabili per poter correttamente approcciare il tema, in particolare dal punto di vista della corretta gestione dei rifiuti e della buona pratica operativa ai fini dellattuazione dei principi delleconomia circolare

IN a previous paper(On the constitution of atoms and molecules) the writer has shown that an explanation of some of the laws of line spectra may be obtained by applying Plancks theory of black radiation to Rutherfords theory of the structure of atoms. In the present paper these considerations will be further developed, and it will be shown that it seems possible on the theory to account for some of the characteristic features of the recent discovery by Stark[ of the effect of an electric field on spectral lines, as well as of the effect of a magnetic field first discovered by Zeeman. It will also be shown that the theory seems to offer an explanation of the appearance of ordinary double spectral lines

THE discovery. of the aberration of light was soon followed by an explanation according to the emission theory. The effect was attributed to a simple composition of the velocity of light with the velocity of the earth in its orbit. The difficulties in this apparently sufficient explanation were overlooked until after an explanation on the undulatory theory of light was proposed. This new explanation was at first almost as simple as the former. But it failed to account for the fact proved by experiment that the aberration was unchanged when observations were made with a telescope filled with water. For if the tangent of the angle of aberration is the ratio of the velocity of the earth to the velocity of light, then, since the latter velocity in water is three-fourths its velocity ill a vacuum, the aberration observed with a water telescope should be fourthirds of its true value.t * This research was carried out with the aid of the Bache Fund. t It may be noticed that most writers admit the sufficiency ot the explanation according to the emission theory of light; while in fact the difficulty is even greater than according to the undulatory theory. For on the emission theory the velocity of light !!lnst be greater in the water telescope, and therefore the angle of aberration should be less; hence, in order to reduce it to its Lrue value, we must make the absurd hypothesis that the motion of the water in the telescope carries the ray of light in the opposite direction

The probability that the most accurate method of determining the solar parallax now available is that resting on the measurement of the velocity of light, has led to the acceptance of the following paper as one of the series having in view the increase of our knowledge of the celestial motions. The researches described in it, having been made at the United States Naval Academy, though at private expense, were reported to the Honorable Secretary of the Navy, and referred by him to this Office. At the suggestion of the writer, the paper was reconstructed with a fuller general discussion of the processes, and with the omission of some of the details of individual experiments.To prevent a possible confusion of this determination of the velocity of light with another now in progress under official auspices, it may be stated that the credit and responsibility for the present paper rests with Master Michelson.Simon Newcomb,Professor, U.S. Navy,Superintendent Nautical Almanac.Nautical Almanac Office,Bureau of Navigation,Navy Department,Washington, February 20, 1880.