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601.
Latif M. A. Tofaz Tania Chaki B. M. Tariqul Islam H. M. Hossain Md. Saddam Kudrat-E-Zahan Md. 《Russian Journal of General Chemistry》2019,89(6):1197-1201
Russian Journal of General Chemistry - A Schiff base containing the nitrogen-sulfur donor chain [(CH3)2N-C6H4-CH=N-NH-C(S)-SCH2C6H5] was prepared by the condensation of... 相似文献
602.
Monochura Saha Sheelbhadra Chatterjee Munshi Sahid Hossain Arijeet Ghude Subhajit Bandyopadhyay 《化学:亚洲杂志》2019,14(24):4659-4664
Metal ions often influence the photoswitching efficiency of a photochromic system. This article reports a one‐dimensional polymer having cyclic azobenzenes coordinated to silver ions that are bridged by nitrates. The coordination polymer (CP‐ 2 ) displays a photoresponsive behavior. The switching ability in the polymer form was faster compared to the parent azobenzene ligand without the metal ions. Azobenzenes are reported to be poorly conducting. Here, although the azobenzene ligand does not show significant electronic mobility, the coordination polymer (CP‐ 2 ) displays a modest conductivity. The conductance in the cis form of the polymer is significantly higher compared to the trans form. Upon exposure to visible light, the cis form undergoes photoisomerization to the trans form with a drastic drop in the electronic mobility. The trans form can be reverted to the cis form thermally or by using UV light. Thus, this system offers a reversible control of the conductivity using light. 相似文献
603.
M M Hossain 《Pramana》1990,34(6):565-573
The absorption characteristics of polyimide (PM) and polyimide fluorocarbon (PMF-2) polymer film were studied at temperatures
ranging from 20 to 230°C. The glass transition or critical temperature of PMF-2 was found at 160°C. Conduction of PMF-2 was
observed due to the upper fluorocarbon layer below the transition temperature while the middle PM layer is important above
this temperature. The time-dependent absorption/resorption current does not satisfy the traditional Curie-Von Schweidler law.
The experimental results of the absorption characteristics are analysed using a simple R-C circuit. 相似文献
604.
Morehouse P Hossain MA Llinares JM Powell D Bowman-James K 《Inorganic chemistry》2003,42(25):8131-8133
A tosylated azacryptand readily protonates at the bridgehead amines, becoming a potential ditopic anion receptor. The in-in conformation of the amines facilitates encapsulation of two bromide guests and represents the first structural evidence that a proton cage cryptate can bind two anions internally. 相似文献
605.
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608.
Ishii T Asai M Makishima A Hossain I Ogawa M Hasegawa J Matsuda M Ichikawa S 《Physical review letters》2000,84(1):39-42
In deep-inelastic collisions of 8 MeV/nucleon 70Zn projectiles with 198Pt, we have found an 8(+) isomer with T(1/2) = 23(1) ns at 4208 keV in 68Ni; the nug(9/2) E2 effective charge was determined to be 1. 5(1)e. In 69Cu, a 19/2(-) isomer with T(1/2) = 22(1) ns at 3691 keV was identified and its decay data were calculated quite accurately by a parameter-free shell model calculation using empirical input parameters. Proton 2p- 1h excitation, fed by another T(1/2) = 39(6) ns isomer at 3827 keV, induces large collectivity in 69Cu. 相似文献
609.
A new method for the separation of trace amounts of palladium from hydrochloric acid and potassium thiocyanate media has been established based on the formation of an ion-pair complex of palladium thiocyanate anion Pd(SCN)4(2-) and the cationic potassium complex of dicyclohexyl- 18-crown-6 (DC18C6) in chloroform. The effect of various factors (solvent, crown ether, potassium thiocyanate, hydrochloric acid, reagent concentration, shaking time, phase volume ratio, composition of the extracted species, foreign ions, etc.) on the extraction and back-extraction of palladium has been investigated. The method can be combined with subsequent FAAS determination of palladium. The procedure was applied to determine palladium traces in chloroplatinic acid and rhodium chloride. 相似文献
610.
Ali Edrissi Hossain Poorzahedy Habibollah Nassiri Mehdi Nourinejad 《European Journal of Operational Research》2013
Natural earthquake disasters are unprecedented incidents which take many lives as a consequence and cause major damages to lifeline infrastructures. Various agencies in a country are responsible for reducing such adverse impacts within specific budgets. These responsibilities range from before to after the incident, targeting one of the main phases of disaster management (mitigation, preparedness, and response). Use of OR in disaster management and coordination of its phases has been mostly ignored and highly recommended in former reviews. This paper presents a formulation to coordinate three main agencies and proposes a heuristic approach to solve the different introduced sub-problems. The results show an improvement of 7.5–24% when the agencies are coordinated. 相似文献