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31.
32.
The preparation and initial in vitro evaluation of a series of potent arachidonate epoxygenase inhibitors and heteroatom analogues of epoxyeicosatrienoic acid are described.  相似文献   
33.
In this article, we construct a commutative unital Banach algebra, in which the property 6a26=6a62 is true for the invertible elements, but cannot be extended to the whole algebra.  相似文献   
34.
From rehydration experiments the hydrates Ba(OH)2 · 8 H2O, Ba(OH)2 · 3 H2O β-Ba(OH)2, · 1 H2O, and γ-Ba(OH)2 · 1 H2O have been found in the system Ba(OH)2-H2O. Thermoanalytical measurements (DTA, TG, DTG, high temperature X-ray diffraction, high temperature Raman scattering) on these hydrates are reported. Thermal decomposition of Ba(OH)2 · 8 H2O and Ba(OH)2 · 3 H2O always results in the formation of β-Ba(OH)2 · 1 H2O, the stable form of the monohydrates at ambient temperature. Dehydration of β- and γ-Ba(OH)2 · 1 H2O, both of which form anhydrous β-Ba(OH)2 as the first product of decomposition, starts at 105 and 115°C, respectively. Single crystals of Ba(OH)2 · 3 H2O and γ-Ba(OH)2 · 1 H2O were prepared from Ba(OH)2 · 8 H2O meltings and from ethanolic solutions of Ba(OH)2 , respectively. The crystal data are: Ba(OH)2 · 3 H2O (orthorhombic, Pnma): a = 764.0(2), b = 1140,3(5), c = 596.5(1) pm, Z = 4; γ-Ba(OH)2 · 1 H2O (monoclinic, P21/m or P21): a = 704.9(2), b = 418.4(1), c = 633.3(1) pm, β = 111.45(2)°, Z = 2.  相似文献   
35.
A series of indolylidinepyrazolones were synthesized using a simple, green, and effective route and evaluated as anti-bacterial agents. The compounds were further studied via structure-guided docking study. One of the compounds exhibiting H-bonding interactions with conserved residue Arg144 turned out to be the most potent compound of the series. The minimum inhibitory concentration values ranged from 50 to 25 μg/mL against Staphylococcus aureus in their anti microbial evaluation.  相似文献   
36.
Polycondensation of the diacid chloride of 2-(3-carboxy vinyl)phenyl-1,3-dioxoisoindoline-5-carboxylic acid with m-phenylenediamine and the diacid chloride of 2-(4-carboxy phenyl)-1,3-dioxoisoindoline-5-carboxylic acid with 1,5-bis(3-aminophenyl)1,4-pentadien-3-one was carried out in polar solvents to produce new unsaturated polyamide–imides. The solution and the thermal, electrical, and a few other properties of the polymers were studies. The polymers were soluble in highly polar solvents. The solubility parameter of the polymers was calculated from the Small's group contribution. The polymers were fairly thermostable and underwent crosslinking creaction when heated, preferably in the presence of a suitable catalyst. The crosslinked polymers were in soluble even in highly polar solvents and possessed higher thermal stability. The swelling behavior of the polymers was studied and the molecular weight between two consecutive crosslinks was determined. X-ray diffraction and the dielectric properties of the polymers and their crosslinked products were also studied.  相似文献   
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38.
Amino endgroups have been incorporated in poly(methyl methacrylate) by two methods: (a) initiation with systems producing amine radicals and (b) chain transfer with amines. A new dye-partition technique with the use of disulfine blue was developed for qualitative and in some cases quantitative estimation of amino endgroups in the polymer.  相似文献   
39.
The possible existence of charmed multiquark hadrons are investigated using phenomenologicalmit bag model and the SU(4) flavour symmetry. The masses of 6q, 9q and 15q systems having the same quantum numbers as the physically interesting ordinary nuclei, hypernuclei and supernuclei are estimated. We find that several new states with distinct signatures are predicted.  相似文献   
40.
Journal of Thermal Analysis and Calorimetry - In this work, the performance enhancement of a HFO-1234yf mobile air conditioning (MAC) system with a suction/liquid line heat exchanger (SLHX) was...  相似文献   
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