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991.
Journal of Thermal Analysis and Calorimetry - The fire behavior of one flame-retardant PVC cable used as building wire is investigated in this work. Bench scale tests were performed using a cone... 相似文献
992.
993.
Hosseini Seyed Ghorban Khodadadipoor Zahra Mahyari Mojtaba Zinab Javad Mohebbi 《Journal of Thermal Analysis and Calorimetry》2019,135(2):963-979
Journal of Thermal Analysis and Calorimetry - The present study reports numerical simulations of water-based Al2O3 nanofluid flowing in a 2D channel with a heated wall-mounted obstacle. The... 相似文献
994.
Mikhailovskii A. G. Peretyagin D. A. Dmitriev M. V. 《Russian Journal of Organic Chemistry》2019,55(5):633-639
Russian Journal of Organic Chemistry - The reaction of 6,6-dialkyl-5,6-dihydrobenzo[f]pyrrolo[2,1-a]isoquinoline-8,9-diones with hydrazine is used to prepare enaminoketohydrazides of the... 相似文献
995.
Majchrzak-Kucęba Izabela Ściubidło Aleksandra 《Journal of Thermal Analysis and Calorimetry》2019,138(6):4139-4144
Journal of Thermal Analysis and Calorimetry - The paper presents the effect of the tabletting pressure and time on the chemical structure and crystallinity of the CuBTC and MIL-53(Al)... 相似文献
996.
Shweta Bhagat Minhajul Arfeen Gourav Das Neha Patel Prasad V. Bharatam 《Journal of computational chemistry》2019,40(5):726-733
Carbocyclic carbenes (CCCs) are a class of nucleophilic carbenes which are very similar to N-heterocyclic carbenes (NHCs) in terms of their reactivity, but they do not contain a stabilizing heteroatom in their cyclic ring system. In this study, 17 representative known CCCs and 34 newly designed CCCs are evaluated using quantum chemical methods, and the results are compared in terms of their stability, nucleophilicity, and proton affinity (PA) parameters. The results are divided on the basis of ring size of the known and reported CCCs. The stability, nucleophilicity, PA, complexation energy, and bond strength–related parameters were estimated using M06/6-311++G(d,p) method. The results indicated that the CCCs known in the literature are strong σ-electron donating species and have considerable π-accepting properties. This study led to the design and identification of a few new CCCs with dimethylamine and diaminomethynyl substituents which can be singlet stable and are substantially nucleophilic. © 2018 Wiley Periodicals, Inc. 相似文献
997.
Monoester‐diterpenoid alkaloids are the main bioactive components of Sini decoction, which is a well‐known traditional Chinese medicine formula for the treatment of myocardial infarction (MI) and heart failure in China. In this work, an ultra‐high‐performance liquid chromatography–mass spectrometry combined with microdialysis method was successfully established and applied for investigating for the first time comparative plasma pharmacokinetics of three monoester‐diterpenoid alkaloids (benzoylmesaconitine, benzoylaconitine and benzoylhypacoitine) in normal and MI rats after oral administration of Sini decoction. The statistical results of pharmacokinetic parameters demonstrated that benzoylmesaconitine, benzoylaconitine and benzoylhypacoitine showed lower peak concentration, longer half‐life, smaller area under the concentration–time curve, slower clearance, time to peak concentration and mean residence time in MI rats than in normal rats (p < 0.05), which indicated that monoester‐diterpenoid alkaloids exhibited lower systemic exposure and slower elimination in the MI rats. The results provided the experimental basis for understanding the metabolic fate and therapeutic effects of Sini decoction. 相似文献
998.
Cavalcanti André D. D. Melo Bruna A. G. Oliveira Rhelvis C. Santana Maria H. A. 《Applied biochemistry and biotechnology》2019,188(2):527-539
Applied Biochemistry and Biotechnology - The effects of ethanol/broth proportions and the number of steps at varying pH in the presence or absence of sodium chloride (NaCl) were studied as... 相似文献
999.
Gatto Claudia C. Chagas Marcio A. S. Lima Iariane J. Mello Andrade Francyelli Silva Hugo D. Abrantes Gabrielly R. Lacerda Elisângela P. S. 《Transition Metal Chemistry》2019,44(4):329-340
Transition Metal Chemistry - The present study reports the synthesis and crystal structures of Cu(II) complexes with pyridoxal S-allyldithiocarbazate (H2L1) and pyridoxal thiosemicarbazones... 相似文献
1000.
The kinetics of the dissipation of chlortetracycline in the aquatic environment was studied over a period of 90 days using microcosm experiments and distilled water controls. The distilled water control experiments, carried out under dark conditions as well as exposed to natural sunlight, exhibited biphasic linear rates of dissipation. The microcosm experiments exhibited triphasic linear rates of degradation both in the water phase (2.7 × 10−2, 7 × 10−3, 1.3 × 10−3 μg g−1 day–1) and the sediment phase (3.4 × 10−2, 6 × 10−3, 1 × 10−3 μg g−1 day–1). The initial slow rate of dissipation in the dark control (3 × 10−3 μg g−1 day–1) was attributed to a combination of evaporation and hydrolysis, whereas the subsequent fast rate (1.8 × 10−3 μg g−1 day–1) was attributed to a combination of evaporation, hydrolysis, and microbial degradation. For the sunlight-exposed control, the initial slow rate of dissipation (1.5 × 10−3 μg g−1 day–1) was attributed to a combination of evaporation, hydrolysis, and photolysis, whereas the subsequent fast rate was attributed to a combination of evaporation, hydrolysis, photolysis, and microbial degradation (5.1 × 10−3 μg g−1 day–1). The initial fast rate of dissipation in the water phase of the microcosm experiment is attributed to a combination of evaporation, hydrolysis, photolysis, and microbial degradation, whereas all subsequent slow rates in the water phase and all rates of degradation in the sediment phase are attributed to microbial degradation of the colloidal and sediment particle adsorbed antibiotic. A multiphase zero-order kinetic model is presented that takes into account (a) dissipation of the antibiotic via evaporation, hydrolysis, photolysis, microbial degradation, and adsorption by colloidal and sediment particles and (b) the dependence of the dissipation rate on the concentration of the antibiotic, type and count of microorganisms, and type and concentration of colloidal particles and sediment particle adsorption sites within a given aquatic environment. 相似文献