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排序方式: 共有1394条查询结果,搜索用时 281 毫秒
271.
Mohamed H. Hekal Fatma S. M. Abu El‐Azm Hanan A. Sallam 《Journal of heterocyclic chemistry》2019,56(3):795-803
A series of new N‐substituted isoquinolin‐1,3‐dione derivatives were prepared, starting from reaction of (Z)‐4‐((E)‐3‐phenylallylidene)isochromane‐1,3‐dione 4 with different nitrogen nucleophiles. The assigned structures of the prepared compounds were elucidated by spectral methods (IR, 1H NMR, 13C NMR, and mass spectroscopy). Some of the newly prepared compounds were tested in vitro against a panel of three human tumor cell lines, namely, hepatocellular carcinoma (liver) HepG2, colon cancer HCT‐116, and mammary gland breast MCF‐7. Also, they were tested as antioxidants. Some of the tested compounds showed very strong cytotoxic activity with respect to the standard. 相似文献
272.
Mat Mohamad Nur Hidayat Asmuin Nor Zelawati Md Basir Md Faisal Safaei Mohammad Reza Mohd Kasihmuddin Mohd Shareduwan Ahmad Khairuddin Taufiq Khairi Godarzi Marjan 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2159-2173
Journal of Thermal Analysis and Calorimetry - One of the important parameters in developing dry ice blasting nozzle is the high-speed dry ice pellets. However, many studies focus primarily only on... 相似文献
273.
Fixed-point theorems for complete intuitionistic fuzzy metric spaces are given. 相似文献
274.
This paper presents an experimental approach to study the capillary impregnation of a liquid across an array of parallel micro-cylinders. The technique presented successfully validates the theoretical findings of part I, and provides a methodology to calculate the fill time and the overall capillary impregnation dynamics for any arbitrary cylindrical sample made of aligned micro-cylinders, by taking into account the role of the trapped gas, which opposes and slows down the inward capillary flow. 相似文献
275.
Alkaline polymer electrolytes (ASPE) have been prepared by using poly(vinyl alcohol) (PVA) polymer and which different weight percentages of potassium hydroxide (KOH), ceramic filler (α-Al2O3), and propylene carbonate (PC) have been added. The pure PVA/H2O weight ratio (1.00:1.49), the PVA/KOH/H2O (1.00:0.67:2.22), the PVA/KOH/α-Al2O3/H2O (1.00:0.67:0.09:7.56), and PVA/KOH/α-Al2O3/PC/H2O (1.00:0.67:0.09:2.64:1.32) were studied. The hysteresis phenomena in the conductivity temperature of ASPE were investigated. The polymer electrolytes prepared were characterized using X-ray diffraction and scanning electron microscopy. 相似文献
276.
Lutz Lameyer Omar Abu Salah Stephan Deuerlein Thomas Stey Dietmar Stalke 《无机化学与普通化学杂志》2004,630(12):1801-1806
The magnesium, calcium, and strontium metal derivatives of 2, 2, 4, 4, 6, 6, 8, 8‐octamethylcyclotetrasilazane (OMCTS) have been synthesized and structurally characterized by X‐ray diffraction studies. These are the first complexes of the homologous series of alkaline earth metalated OMCTS. Similar to the homologous series of the corresponding alkali metal complexes, the structural properties show remarkable tendencies in the series from magnesium to strontium. The magnesium dication causes the most pronounced deformation along the transannular N‐···N‐ vector of the [(c‐N‐SiMe2‐NH‐SiMe2‐)2]2‐ dianionic ring. The lengths of the Si‐N bonds are correlated to the bond types, so that shorter distances result when the bonds become more ionic. The difference between the long Si‐N(H) bonds and the short Si‐N‐ bonds decreases gradually with the increasing mass of the alkaline earth metal dication. 相似文献
277.
Cylindrical pellets were made by mixing ion-exchange resin particles with binding powders and heating to 140°C. To compare catalytic activities of these resin pellets with those of resin particles and sulfuric acid, the esterification of palmitic acid with isobutyl alcohol was carried out in a batch reactor. The rate equation for sulfuric acid could be applied to ion-exchange resins although the values of parameters were different. 相似文献
278.
Mohamad K. Abdullah Suhairi Shaharudin Mohd Adzir Mahdi Rosdisham Endut 《Optics & Laser Technology》2004,36(7):313-570
This paper presents a tunable hybrid brillouin-erbium fiber laser system with a maximum tuning range of more than 36.7 nm. The system was configured in a ring set-up with another fiber laser used as the brillouin pump at about 8 mW maximum launched power. Stable Stokes signals at an average of about 0.08 nm wavelength shift were observed across the tuning range. The dependency of the Stokes signal tuning range on the laser's spectral gain is also elaborated. 相似文献
279.
Rahul Bhowmick Abu Saleh Musha Islam Mihir Sasmal Atul Katarkar 《Journal of Coordination Chemistry》2018,71(11-13):2065-2081
A new, highly sensitive probe L2 for the selective detection of Hg2+ in organo-aqueous (H2O:CH3CN, 1:1, v/v, HEPES buffer, pH 7.2) medium has been synthesized from rhodamine 6G-hydrazide and 4-nitroindole-3-carboxaldehyde. It was thoroughly characterized by physicochemical techniques including single crystal X-ray diffraction studies. The reaction of L2 with Hg2+ gives a 1:1 stoichiometry resulting in a 146 fold fluorescence enhancement and a binding constant (Kf) of 3?×?104 M?1. The spirolactam form of the probe is non-fluorescent; however, it shows dual channel (absorbance and fluorescence) recognition of Hg2+ via CHEF effect through the opening of the spirolactam ring. The quantum yields of L2 (0.00045) and L2-Hg2+ (0.29) show the higher stability of complex in the excited state over the free ligand. The 44.5?nM LOD value demonstrates the detection of Hg2+ at a very low concentration range. Cell imaging studies show the cytoplasmic recognition of Hg2+ by L2. Experimental results are comparable with theoretical values obtained by DFT studies. The fluorescence emission of the complex was completely quenched by I- and from the reversibility studies an advance level INHIBIT logic gate and memory device can be framed. 相似文献
280.
通过离子液体氯化1-苄基-3-甲基咪唑(BenzMeIm-Cl)与PtCl2的反应,合成了配合物(BenzMeIm)2[PtCl4],并用元素分析、红外光谱、紫外-可见光谱、1H NMR、13C NMR和单晶X射线衍射对其进行了表征。单晶X射线分析表明,配合物结构属于P21/c空间群,晶胞参数和结构解析参数为:a=0.981 80(5)nm,b=0.861 47(3)nm,c=0.144 332(7)nm,β=92.480(2)°,V=121.96(1)nm3,R1=0.014 4,wR2=0.038 8。 相似文献