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71.
Hashmi AS Rivas Nass A Bats JW Bolte M 《Angewandte Chemie (International ed. in English)》1999,38(22):3370-3373
Unexpected stability is observed for the palladacycloheptane rac-2, which is obtained as major product and single diastereomer from the cyclization of 1 and Pd(0). Up to a temperature of 50 degrees C 2 shows neither reductive elimination nor intramolecular insertion of another olefin. 相似文献
72.
The kinetics of electron transfer between chromium(VI) and H3PO3, yielding chromium(III), have been investigated in HClO4
and H2SO4 media by visible spectrophotometry. The rate of reaction increased with increasing [H2SO4] and [HClO4]. A rate law
based on ester formation preceding the electron transfer has been established and a possible mechanism has been proposed.
The mechanism and the derived rate law are consistent with the observed kinetics.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
73.
M. H. Hashmi A. A. Ayaz Maqbool Ahmad Shahid 《Fresenius' Journal of Analytical Chemistry》1965,211(6):417-419
Summary A simple, accurate and rapid method is described for the determination of hydrazine by direct titration with hypobromite using Bordeaux B as indicator. The procedure can also be employed for the determination of hypobromite and bromate by titration with standard hydrazine.
Zusammenfassung Zur Bestimmung von Hydrazin wird die direkte Titration mit Hypobromitlösung und Bordeaux B als Indicator empfohlen. Das Verfahren ist einfach, rasch durchführbar und liefert genaue Ergebnisse. Es kann auch zur Bestimmung von Hypobromit und Bromat durch Titration mit Hydrazinlösung verwendet werden.相似文献
74.
Rajkumar Joshi Guruaribam Shashikumar Sharma Vikrant Kumar Athar Adil Hashmi Satyendra Kumar R. Achila M. Ejaz Hussain 《应用有机金属化学》2006,20(11):740-746
A heteroscorpionate ligand, potassium hydrobis(benzoato)(salicylaldehyde)borate (KL), has been synthesized. This was converted into organotin complexes R2SnL2 and R3SnL complexes by mixing and stirring with a methanolic solution/suspension of organotin chloride. The ligand and its complexes were characterized by elemental analyses and spectral studies (IR, 1H NMR, 13C NMR, ESI mass spectra and Thermo gravimetric analysis (TGA)). Antibacterial and antifungal studies of these compounds were evaluated by the disc diffusion method at variable concentration against three species of bacteria (Staphylococcus aureus, Klebsiella pneumonia and Bacillius subtillis) and two species of fungi (Asperjillius fiavus and Candida albicans). It was found that triorganotin derivatives (R3SnL) of the ligand were more effective as compared with diorganotin derivatives (R2SnL2). The organotin complexes of borates were tested for their algicidal activity on the cyanobacterial strains Aulosira fertilissma, Anabaena species, Anabaena variabilis and Nostoc muscorum and showed high to moderate toxicity towards the above species. The ligand and its complexes were also tested for its pH effect on soil in vitro for a duration of more than one month and it was found that they are able to kill pests without damaging the soil quality. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
75.
M. H. Hashmi Manzoor Ahmad Chaudhry N. A. Chughtai Riaz-ur-Rehman 《Mikrochimica acta》1970,58(2):200-206
Summary The effect of various factors such as thickness of layer, acidity, activation of layer, amount of sample spotted, time interval for the flow of solvent, saturation of developing chamber, etc. have been studied using circular TLC apparatus and suitable conditions for micro-analysis by circular thin-layer chromatography are recorded. Comparative study with linear TLC is made to evaluate advantages of circular TLC in microanalysis.
Zusammenfassung Der Einfluß der Schichtdicke, der Acidität, der Aktivierung des Schichtmaterials, der aufgetragenen Probenmenge, der Dauer des Lösungsmittelflusses, der Sättigung der Kammeratmosphäre usw. auf die Dünnschicht Ringchromatographie wurde geprüft und geeignete Arbeitsbedingungen ausgearbeitet. Im Vergleich zur linearen DC wurden die Vorteile hervorgehoben.相似文献
76.
Manzur-ul-Haque Hashmi Gul Akhtar Minhas Mohammad Iqbal Durrani Riaz-ur-Rehman 《Mikrochimica acta》1969,57(2):286-289
Summary A method for the preparation of ore solutions by grinding the ore with distilled water is developed for the analysis of minerals and ores in the field by the circular thin-layer Chromatographic technique.
Zusammenfassung Die Herstellung von Erzlösungen durch Mahlen des Erzes mit dest. Wasser zur Feldanalyse von Mineralen und Erzen durch Ring-Dünnschichtchromatographie wird empfohlen.相似文献
77.
78.
79.
Jan W. Bats Andreas Rivas Nass A. Stephen K. Hashmi 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):814-817
The crystal structure of the title compound, (2,2′‐bipyridyl‐κ2N,N′)(tetraallyl 3,3,3′,3′‐tetramethyl‐1,1′‐bicyclopropane‐1,1′,2,2′‐tetracarboxylato‐κ2C2,C2′)palladium(II), [Pd(C26H32O8)(C10H8N2)], is disordered above 194 K. A doubling of the unit cell is observed on cooling. The structure at 143 K contains two ordered molecules related by a pseudo‐translation vector of approximately (0.44,0.00,0.50) or a pseudo‐inversion center at approximately (0.22,0.00,0.25). Weak intermolecular C—H?O interactions are enhanced in the low‐temperature structure. 相似文献
80.
Dr. Kohei Sekine Jürgen Schulmeister Dr. Fabian Paulus Dr. Katelyn P. Goetz Dr. Frank Rominger Dr. Matthias Rudolph Prof. Dr. Jana Zaumseil Prof. Dr. A. Stephen K. Hashmi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(1):216-220
The gold-catalyzed facile synthesis of U-shaped and S-shaped bispentalenes is described from easily available tetra(arylethynyl)-benzenes and -naphthalenes. The optoelectronic and transistor properties were also investigated. The selectivity between the U-shaped and S-shaped bispentalene isomers can be tuned by the bulkiness of the ligand and the substrates. The S-shaped naphthalene-based bispentalene shows a one-dimensional face-to-face packing pattern in solid state and a good hole mobility, indicating that the S-shaped bispentalene core is highly suitable for transistor applications. The gold-catalyzed annulation of tetraynes provides a useful protocol in the synthesis of bispentalenes for organic semiconductors. 相似文献