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131.
二乙胺基乙腈分別与苯邻二酰亚胺、丁二酰亚胺或邻-磺酰苯酰亚胺反应后,可生成相应的N-氰甲基苯邻二酰亚胺、N-氰甲基丁二酰亚胺,N-氰甲基邻磺酰苯酰亚胺及O-氰甲基邻磺酰苯酰亚胺。酰亚胺或磺酰苯酰亚胺的氰甲基化反应活性,随氮负离子的稳定性及其酸性增强而增大。  相似文献   
132.
133.
谌丛菊  邓风  岳勇 《物理化学学报》1998,14(10):940-944
The relaxation properties of water saturated in porous core are discussed and the distribution of proton transverse relaxation time and bi-exponential model of longitudiual relaxation time are obtained, which provide an illustration for two-model of fluids saturated in porous media. The cutoff value of T_1 based on relaxation specific property of fluids in porous core is adopted to improve the correlation between permeability and ?4T1b2.  相似文献   
134.
Novel functional microspheres with multistimuli-responsive properties have been prepared and characterized. The as-prepared microspheres respond to an external magnetic field, environmental temperature, and ultraviolet radiation. The in vitro drug-loading efficiency and drug-release behavior of these microspheres demonstrated that they could be used as drug carriers for drug controlled release. The results of in vivo distribution investigations of these microspheres showed that they exhibit a high magnetic-targeting effect, which holds promise for applications in various fields such as magnetic drug targeting and tissue labeling, among others.  相似文献   
135.
Four distinct biochars were employed to remove three typical pollutants, meanwhile, path analysis, a multi-statistical regression method, was performed to elucidate the dominant factors of biochar adsorption. This work can provide a new insight to prepare a targeted biochar as adsorbents.  相似文献   
136.
铽与邻氨基苯基苯甲酸配合物的合成、表征及荧光性质   总被引:2,自引:0,他引:2  
选择不同的pH值,在乙醇-水溶液中合成了铽与邻氨基苯基苯甲酸固体配合物.通过元素分析、摩尔电导、热分析、红外光谱、紫外光谱,表征并确定了配合物的化学组成为TbL4K·nH2O(n=1,2).同时,在不同pH值下合成得到的配合物的荧光性质也得到了测试和讨论,表明pH=10.0时配合物TbL4K·2H2O在544 nm处5D4→7F5跃迁的发射峰为最强.  相似文献   
137.
Upon the Liu, Siegbahn, Truhlar, Horowitz (LSTH) potential energy surface, the reaction probabilities of the three-dimensional (3-D) state-to-state H + H2 (v, j) →H 2(v′, j′) + H reaction are calculated with the linear combination of arrangement channels-scattering wavefunction (LCAC-SW) method. In the calculation, the vibration function of H2 and the radial propagating wave functions are expanded by the real Gauss functions. The calculated threshold energy and the resonating structure are consistent with the results of the accurate quantum scattering calculations, which shows the accuration, simplicity and practicability of the LCAC-SW method. Project supported by the National Natural Science Fondation of China and the Doctoral Foundation of the State Education Commission of China.  相似文献   
138.
Isomeric structures and energies of three kinds of lithofluorosilylenoids, R2SiLiF (R = NH2, OH, F) were studied using theab initio molecular orbital theory. The calculations show that thermal stability of the three-membered ring structures of these three kinds of silylenoids decreases in the order of substituents NH2 > OH > F because of the conjugation between NH2, OH or F and Si atom. The interaction of substituents R with Li atom makes R2SiLiF have a structure with two Li-A-Si-F (A = N, O, F) four-membered rings, which is the most stable of the isomers of each of three kinds of silylenoids and whose stability decreases in the order of substituents F > OH > NH2. Inductive effect of substituents influences the thermal stability of the linear structure of silylenoids.  相似文献   
139.
The merocyanine dye 3-ethyl-5-(2-(3-ethyl-2-benzothiazolinylidene)-ethylidene)-rhodanine (BTER) known as Agfa-10 has been found to have a good photoconductivity as solution cast film. In this paper iodine-doped BTER was obtained by doping with iodine vapor. Its structure was investigated with the following characteristies. 1 The doped iodine had been excited as I_3~- anion. 2 Because the electron located on the sulphur atom was transferred to iodine, the charge transfer complex of (BTER-I_3) formed. 3 During the iodine doping process, BTER changed from α-form to β-modification. These had been identified by X-ray diffraction, VIS-absorption spectra and SEM picture.4 From the volt-Ampere curve obtained from sandwich cell, when E≤2.2×10~(-1) V·cm~(-1), the room temperature electrical conductivity of BTER and BTER-I_3 were found to be 2.22×10~(-10) s·cm~(-1) and 2.6×10~(-7) S·cm~(-1), respectively.  相似文献   
140.
The principle of methyl scanning is proposed for determination of the sites of interaction between biologically active small molecules and their macromolecular target(s). It involves the systematic preparation of a family of methylated derivatives of a compound and their biological testing. As a functional assay, the method can identify the regions of a molecule that are important (and unimportant) for biological activity against even unknown targets, and thus provides an excellent complement to structural biology. Methyl scanning was applied to demethylasterriquinone B1, a small-molecule mimetic of insulin. A new, optimal total synthesis of this natural product was developed that enables the family of methyl scan derivatives to be concisely prepared for evaluation in a cellular assay. The results of this experiment were used to design a biotin-demethylasterriquinone conjugate for use as an affinity reagent. This compound was prepared in tens of milligram quantities in a four-step synthesis.  相似文献   
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