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O. Schmitz-Du Mont 《Monatshefte für Chemie / Chemical Monthly》1968,99(4):1285-1288
Ohne ZusammenfassungMit 2 Abbildungen 相似文献
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Hrib CG Jeske J Jones PG du Mont WW 《Dalton transactions (Cambridge, England : 2003)》2007,(32):3483-3485
Formally uncharged two-coordinate tellurium atoms in trialkyl(telluroseleno)phosphonium salts [(tBu2iPrPSeTe-p-Tol)+ (p-TolTeI2)-] () and {[(iPr3PSeTeI)+]2 (TeI6)2-} () behave as soft acceptors towards iodotellurate anions, thus exhibiting a novel type of Te...Te anion-->cation donor-acceptor interaction () and a chelating TeIV(micro-I)2TeII anion-cation coordination () in the solid state. 相似文献
66.
Francisco J. Montáns Francisco Chinesta Rafael Gómez-Bombarelli J. Nathan Kutz 《Comptes Rendus Mecanique》2019,347(11):845-855
In the past, data in which science and engineering is based, was scarce and frequently obtained by experiments proposed to verify a given hypothesis. Each experiment was able to yield only very limited data. Today, data is abundant and abundantly collected in each single experiment at a very small cost. Data-driven modeling and scientific discovery is a change of paradigm on how many problems, both in science and engineering, are addressed. Some scientific fields have been using artificial intelligence for some time due to the inherent difficulty in obtaining laws and equations to describe some phenomena. However, today data-driven approaches are also flooding fields like mechanics and materials science, where the traditional approach seemed to be highly satisfactory. In this paper we review the application of data-driven modeling and model learning procedures to different fields in science and engineering. 相似文献
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Roxana M. Bîrzoi Dr. Delia Bugnariu Dr. Rafael Guerrero Gimeno Dr. Daniela Lungu Vera Zota Dr. Constantin Daniliuc Dr. Peter G. Jones Prof. Dr. Zoltán Benkõ Dr. László Könczöl László Nyulászi Prof. Dr. Rainer Bartsch Dr. Wolf‐W. du Mont Prof. Dr. Edgar Niecke Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(16):4843-4851
Deprotonation of aminophosphaalkenes (RMe2Si)2C?PN(H)(R′) (R=Me, iPr; R′=tBu, 1‐adamantyl (1‐Ada), 2,4,6‐tBu3C6H2 (Mes*)) followed by reactions of the corresponding Li salts Li[(RMe2Si)2C?P(M)(R′)] with one equivalent of the corresponding P‐chlorophosphaalkenes (RMe2Si)2C?PCl provides bisphosphaalkenes (2,4‐diphospha‐3‐azapentadienes) [(RMe2Si)2C?P]2NR′. The thermally unstable tert‐butyliminobisphosphaalkene [(Me3Si)2C?P]2NtBu ( 4 a ) undergoes isomerisation reactions by Me3Si‐group migration that lead to mixtures of four‐membered heterocyles, but in the presence of an excess amount of (Me3Si)2C?PCl, 4 a furnishes an azatriphosphabicyclohexene C3(SiMe3)5P3NtBu ( 5 ) that gave red single crystals. Compound 5 contains a diphosphirane ring condensed with an azatriphospholene system that exhibits an endocylic P?C double bond and an exocyclic ylidic P(+)? C(?)(SiMe3)2 unit. Using the bulkier iPrMe2Si substituents at three‐coordinated carbon leads to slightly enhanced thermal stability of 2,4‐diphospha‐3‐azapentadienes [(iPrMe2Si)2C?P]2NR′ (R′=tBu: 4 b ; R′=1‐Ada: 8 ). According to a low‐temperature crystal‐structure determination, 8 adopts a non‐planar structure with two distinctly differently oriented P?C sites, but 31P NMR spectra in solution exhibit singlet signals. 31P NMR spectra also reveal that bulky Mes* groups (Mes*=2,4,6‐tBu3C6H2) at the central imino function lead to mixtures of symmetric and unsymmetric rotamers, thus implying hindered rotation around the P? N bonds in persistent compounds [(RMe2Si)2C?P]2NMes* ( 11 a , 11 b ). DFT calculations for the parent molecule [(H3Si)2C?P]2NCH3 suggest that the non‐planar distortion of compound 8 will have steric grounds. 相似文献
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M. Bätcher W.-W. Du Mont S. Pohl W. Saak 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):147-150
Abstract Neutral species R3PX2 in equilibria with halogenophosphonium halides R3PX+X? do not always contain hypervalent phosphorus (10-P-5)! Iodophosphonium ions R3PI+ show R3P-I… X interaction in many cases, leading to hypervalent iodine (10-I-2). Evidence for secondary IX bonds is provided by n.m.r. spectra and X-ray crystal structure determinations. 相似文献
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Estela Lladosa Juan B. Montón MaCruz Burguet Javier de la Torre 《The Journal of chemical thermodynamics》2008,40(5):867-873
Isobaric (vapour + liquid + liquid) equilibria were measured for the (di-n-propyl ether + n-propyl alcohol + water) and (diisopropyl ether + isopropyl alcohol + water) system at 100 kPa.The apparatus used for the determination of (vapour + liquid + liquid) equilibrium data was an all-glass dynamic recirculating still with an ultrasonic homogenizer couple to the boiling flask.The experimental data demonstrated the existence of a heterogeneous ternary azeotrope for both ternary systems. The (vapour + liquid + liquid) equilibria data were found to be thermodynamically consistent for both systems.The experimental data were compared with the estimation using UNIQUAC and NRTL models and the prediction of UNIFAC model. 相似文献