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71.
Namita Singh Sana Ahmed Aliyah Fakim Somayah Qutub Othman Alahmed Omar El Tall Osama Shekhah Mohamed Eddaoudi Niveen M. Khashab 《Chemical science》2020,11(41):11280
Assembling well-defined MOF superstructures remains challenging as it requires easily removable hard templates or readily available immiscible solutions for an emulsion-based soft-template approach. In this work, a single-step emulsion-free soft templating approach is reported to spontaneously prepare hollow ZIF-8 and ZIF-67 colloidosomes with no further purification. These superstructures can load different enzymes regardless of the size and charge with a high encapsulation efficiency of 99%. We envisage that this work will expand the repertoires of MOF superstructures by the judicious selection of precursors and the reaction medium.An emulsion-free approach for the preparation of hollow ZIF-8 superstructures in a single step is established based on metal sulfate hydrates in methanol. 相似文献
72.
Ahmad Banihashemi C. S. Marvel 《Journal of polymer science. Part A, Polymer chemistry》1977,15(11):2667-2672
Polymers made from 2,2′-diiododiphenyl-4,4′-dicarbonyl dichloride, diphenyl ether, and isophthaloyl chloride have been made and converted to the 2,2′-diphenylethynyl derivatives. Introduction of units of isophthaloyl chloride reduced the melting point of these polymers to about 200°C, and they could then be cured by heating. A good glass laminate was prepared and cured from one of the polymers. 相似文献
73.
Analysis Mathematica - 相似文献
74.
Summary
Bis(cyclopentadienyl)titanium(IV) diisothiocyanate [(Cp)2-Ti(NCS)2] reacts with MCl2 (M = Cu, Pd or Pt), [CuCl(PPh3)3], [RuCl2(PPh3)3] and [RuCl2(DMSO)4] (DMSO = dimethylsulphoxide) giving solid compounds of stochiometry [(Cp)2Ti(-NCS)2MCl2] (M = Cu, Pd or Pt), [(Cp)2Ti(-NCS)2CuCl(PPh3)], [(Cp)2Ti(-NCS)2-RuCl(PPh3)2]Cl and [(Cp)2Ti(-NCS)2RuCl2(DMSO)2]. These products have been characterized by physicochemical and spectroscopic methods. 相似文献
75.
Lopez-Martens A Hannachi F Dossing T Schück C Collatz R Gueorguieva E Vieu C Leoni S Herskind B Khoo TL Lauritsen T Ahmad I Blumenthal DJ Carpenter MP Gassmann D Janssens RV Nisius D Korichi A Bourgeois C Astier A Ducroux L Le Coz Y Meyer M Redon N Sharpey-Schafer JF Wilson AN Korten W Bracco A Lucas R 《Physical review letters》1996,77(9):1707-1710
76.
77.
A. El Sayed S. S. Abd El Rehim H. Mansour 《Monatshefte für Chemie / Chemical Monthly》1991,122(12):1019-1027
Summary The electrochemical behaviour of pure indium in KOH solutions (1–4M) was studied at different temperatures (25–70°C) by potentiostatic techniques. Two anodic peaks corresponding to the formation of In(OH)3 and In2O3 were observed. The heights of the two peaks increased with the increase of alkali concentration. An increase of temperature increased the peak currents and shifted their corresponding potentials to more negative values. The variation of the peak currents and peak potentials with scan rate suggested that the anodic dissolution of indium was a diffusion controlled process. In cyclic voltammetry, the reverse scan consistently showed one peak which was attributed to the reduction of anodic oxidation products into indium. X-ray diffraction analysis confirmed the presence of In(OH)3 at the first anodic peak, In(OH)3 and In2O3 at the second anodic peak and In2O3 in the permanent passive region.
Zum elektrochemischen Verhalten einer Indium-Elektrode in konzentrierter Kalilauge bei verschiedenen Temperaturen
Zusammenfassung Es wurde das Verhalten von reinem Indium in 1 – 4M KOH-Lösungen bei Temperaturen zwischen 25 und 70°C mittels potentiostatischer Methoden untersucht. Zwei anodische Peaks, entsprechend der Bildung von In(OH)3 und In2O3, traten auf. Die Höhe der beiden Peaks wurde mit zunehmender Alkalikonzentration gesteigert. Eine Temperaturerhöhung verstärkte die Peakströme und verschob die entsprechenden Potentiale zu negativeren Werten. Die Abhängigkeit der Peakströme und Peakpotentiale von der Scangeschwindigkeit legte den Schluß nahe, daß die anodische Lösung von Indium in einem diffusionskontrollierten Prozeß stattfindet. Bei der cyclischen Voltammetrie zeigte der reverse Scan einheitlich einen Peak, der der Reduktion der anodischen Oxidationsprodukte zu Indium zugeschrieben wurde. Röntgendiffraktionsanalyse bestätigte die Präsenz von In(OH)3 beim ersten anodischen Peak, In(OH)3 beim zweiten Peak und In2O3 im permanent passiven Bereich.相似文献
78.
G. Vourlias N. Pistofidis D. Chaliambalias K. Chrissafis El. Pavlidou G. Stergioudis 《Journal of Thermal Analysis and Calorimetry》2007,87(2):401-409
Zinc coatings on ferrous substrates are possible to be applied with
thermal spraying. In the present work the corrosion behavior of zinc thermal
sprayed coatings deposited on low carbon steel St-37 was examined in a simulated
marine atmosphere (salt spray chamber-SSC) and in a dry atmosphere at elevated
temperature (400°C). The corrosion progress was examined by means of optical
microscopy, scanning electron microscopy, X-ray diffraction and thermogravimetric
analysis. From this investigation it was deduced that in the SSC the coating
is uniformly corroded, while the main corrosion products are hydrated zinc
oxides and chlorides. By contrast at 400°C only a thin, compact and continuous
film of ZnO is formed on top of the coating, which remains adherent to the
ferrous substrate. 相似文献
79.
A brief treatment of 2-thiopyrimidine nucleosides (s2U∗) with trans-2-phenylsulfonyl-3-phenyloxaziridine (PSO) results in efficient substrate desulfurization leading to the corresponding 4-pyrimidinone analogues (H2U∗). The key transformation proceeds through oxidation of the 2-thiocarbonyl group to a sulfur oxyacid derivative and subsequent elimination of sulfur dioxide. 4-Pyrimidinone 1-β-d-riboside (H2U) has been transformed into the respective phosphoramidite, a ready-to-use monomer for the introduction of a modified nucleoside into an oligonucleotide chain. Moreover, the effective desulfurization of the 2-thiouridine nucleotide could be achieved directly at the oligonucleotide level, by treatment of the TdA(s2U)dGdC oligonucleotide with PSO, as verified by MALDI-TOF mass spectrometry. 相似文献
80.