2,053 research outputs found
Facile enhancement of the active catalytic sites of N-doped graphene as a high performance metal-free electrocatalyst for oxygen reduction reaction
No full textA simple and facile N-doping process has been developed to prepare graphene nanosheets with a high loading of active catalytic sites through the combination of hydrothermal and microwave processes. High resolution transmission electron microscopy, X-ray photoelectron spectroscopy and Raman analysis have been used to characterize the morphology and composition of the prepared materials. Also, linear sweep voltammetry (LSV) was conducted to investigate the electrocatalytic performance of the N-doped specimens toward oxygen reduction reaction (ORR). It was revealed that post-treatment of hydrothermally-treated N-doped graphenes under microwave irradiation in the presence of nitrogen precursor can result in the formation of a large content of quaternary nitrogen functionalities. Also, the LSV analysis revealed that fabrication of the graphene nanosheets under the proposed N-doping strategy resulted in potent electrocatalytic activity of graphene nanosheets toward ORR through a four electron pathway. © 20181
Diorganotin(IV) complexes with 2-furancarboxylic acid hydrazone derivative of benzoylacetone : synthesis, X-ray structure, antibacterial activity, DNA cleavage and molecular docking
No full textTwo new diorganotin(IV) complexes, Me2SnL and Ph2SnL, have been synthesized from the reaction of
Me2SnCl2 and Ph2SnCl2 with the hydrazone H2L [H2L 1⁄4 (Furan-2-yl) (5-hydroxy-3-methyl-5-phenyl-4,5-
dihydro-1H-pyrazol-1-yl)-methanone] derived from furan-2-carbohydrazide and benzoylacetone. The
new compounds have been characterized by elemental and spectroscopic analyses. The crystal structures
of the monohydrate form of the ligand and of the Me2SnL derivative have been also determined by X-ray
crystallography. Experimental evidences confirm the existence of the hydrazone ligand exclusively in
cyclic form in both solution and solid state. On coordination to tin the hydrazone undergoes a ring
opening reaction and a doubly deprotonation to act as a tridentate ligand via imine nitrogen and enolic
oxygens. The tin atom in the complexes is five coordinate with geometry between square-pyramidal and
trigonal-bipyramidal. The in vitro antibacterial activity of ligand and its complexes has been evaluated
against Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Escherichia coli
and Pseudomonas aeruginosa) bacteria. The interaction between compounds with bacterial DNA was also
studied by molecular docking. Our findings indicate that diphenyltin(IV) complex, by binding to DNA via
minor groove to TATA sequence in genes upstream, has good activities along with the standard antibacterial
drugs. Our agarose-gel electrophoresis experiments show that the ligand exert DNA cleavage,
while Me2SnL and Ph2SnL did not
Esperienza ed evento della verità. Pratica filosofica e astrazione scientifica nel pensiero di A.N. Whitehead
No full textThis article analyzes the relationship between philosophy, experience and event in A.N. Whitehead’s thought. From the critics of the concept of object, the author retraces and describes the peculiar “abstract-concrete dialectic”, at the center of the researches concerning the perceptual experience.
Furthermore, according to Whitehead’s later works, she demonstrates how the philosophical practice is different from all other kinds of science, although it requires science itself because of the co-implication of object and event, abstraction and recognition
Il "Guerrin Meschino" di Gesualdo Bufalino : un'"opra" in versi
No full textGesualdo Bufalino first published Il Guerrin Meschino in 1991 in a non-commercial edition. In 1993, after a deep revision, he re-published his work with publisher Bompiani: the novel has a modified plot, and the author decided to insert three new poems in addition to the opening and closing poems, formerly present in 1991’s edition. This paper, in its entirety supported by handwritten material preserved at Fondazione Gesualdo Bufalino (Comiso), is divided in two parts: the first part illustrates the differences between the first and the second edition, the second part provides a critical edition of the five poems
A FEW WORDS ABOUT THE TEACHER. IN MEMORY OF THE EXCELLENT TEACHER AND SCIENTIST M.R. SAPIN
No full textM.R. Sapin (1925–2015) was a professor at I.M. Sechenov First Moscow State Medical University, honorary academician of Russian academy of medical sciences (1988), and an outstanding representative of the Moscow anatomical school of the middle of XX – early XXI century. From the very beginning of his medical training, Mikhail Romanovich got interested in anatomy, especially in angiology and lymphology, and later concentrated on its studying. The author of more than 30 text books and guidelines for schools, universities, and colleges, Mikhail Romanovich was the doctoral and thesis advisor of 51 Ph.D. and approximately 70 MD dissertations. M.R. Sapin made a significant contribution to the development of anatomical education providing the departments with a various range of dry and wet specimens. His stunning and effective work as a tutor was highly appreciated by his students and colleagues, Russian and foreign anatomists. M.R. Sapin was the leader of the Laboratory of Functional Anatomy since 1972, president of the International Association of Morphologists (1992–2006), chairman of the expert commission of Higher Attestation Commission (1959–1994), etc. A man of a great willpower, M.R. Sapin faced a lot of obstacles in his life and research work but overcame that all successfully. The article presents the most important facts of anatomist’s career and lifetime.</jats:p
Verslag van het voorgevallene tijdens het hooge opperwater op de Nederlandsche rivieren in den winter van 1919 op 1920
No full textNadat de Rijn op 20 December 1919 tot even beneden den middelbaren zomerstand 1901-1910 (M.R.) was gedaald vertoonde zich op die rivier een sterke en vrij snelle was, waardoor het water te Keulen tot 6m +M.R. bij het einde van het jaar steeg. In de daarop volgende 11 dagen daalde de waterstand tot 1.5m +M.R. om daarna in 5 dagen weder te rijzen tot den zeer hoogen stand van 7m +M.R. Door een aanvankelijk sterken later flauweren val liep de stand weder terug tot 1.5m +M.R. op 30 Januari. Ook op de Maas vertoonden zich twee dicht op elkaar volgende sterke wassen. Bij den aanvang van den eersten was op 19 december stond het water te Maastricht op ruim 1m +M.R. en steeg het in 6 dagen tot 4.37m +M.R.; in de daaropvolgende 9 dagen bleef de stand steeds hoger dan 4m +M.R. en daalde toen tot ongeveer 2m +M.R. op 10 Januari 1920. De tweede was trad op laatsgenoemde datum in waarbij het water oplied tot 4.94m +M.R. op 15 Januari. Het water daalde daarna dadelijk en was op 29 Januari tot ongeveer 2m +M.R. weggevallen. Bij den tweeden was op Rijn en Maas werden de hoogst bekende waterstanden bij open rivieren overtroffen te Keulen met 7 cm en te Maastricht met 2 cm. De rivieren waren ijsvrij.Hoogwaterversla
Seismic prevention and rahabilitation of nonstructural elements. Criteria to define a post-seismic damage analysis procedure
No full textIt reports very briefly the research work, developed by the author during her Doctorate course, about a post-seismic damage analysis procedure for nonstructural elements of framed structure building system
The Ontology of the Causal Basis of Man : To the Theory of Time
No full textIn 2014, Amirbegov Y.M.'s monograph titled "Mechanics of Thinking" or "Ontological Basis of the Subject" was published, which dealt with a philosophical question: the relationship of matter with consciousness and time of our being. But since the monograph duplicated the thesis conceived by the author and did not go beyond the material presented in it, on the advice of the consultant the author of the monograph is preparing its second edition in an expanded version with a new title: " Ontology of Causal Basis of Man", attracting his mentor, the author of "The Theory of Time or Principle of Formation of Matter Forms" Amirbegov M.R., as a co-author of this book,
Adhering to the opinion that matter between past and future temporal conti-nuity of eternity is reduced to nothing and in reality there remains only a causeless "Nothing", the authors of this book from a clean sheet, but with baggage of knowledge about objective forms of being and causeless reality with its possibili-ties, build an unparalleled theoretical model of human integrity, answering the question: what does a man, his sensorium, consciousness, his thinking apparatus and thought itself, why and how? The authors submit this book to the judgment of the reader
The Ontology of the Causal Basis of Man : To the Theory of Time
No full textIn 2014, Amirbegov Y.M.'s monograph titled "Mechanics of Thinking" or "Ontological Basis of the Subject" was published, which dealt with a philosophical question: the relationship of matter with consciousness and time of our being. But since the monograph duplicated the thesis conceived by the author and did not go beyond the material presented in it, on the advice of the consultant the author of the monograph is preparing its second edition in an expanded version with a new title: " Ontology of Causal Basis of Man", attracting his mentor, the author of "The Theory of Time or Principle of Formation of Matter Forms" Amirbegov M.R., as a co-author of this book,
Adhering to the opinion that matter between past and future temporal conti-nuity of eternity is reduced to nothing and in reality there remains only a causeless "Nothing", the authors of this book from a clean sheet, but with baggage of knowledge about objective forms of being and causeless reality with its possibili-ties, build an unparalleled theoretical model of human integrity, answering the question: what does a man, his sensorium, consciousness, his thinking apparatus and thought itself, why and how? The authors submit this book to the judgment of the reader
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