杂多阴离子柱撑锰铝水滑石的合成、表征及催化性能

杂多阴离子柱撑锰铝水滑石的合成、表征及催化性能刘继广，孙铁，蒋大振（吉林大学化学系，长春１３００２３）关键词杂多阴离子，柱撑，锰铝水滑石，异丁烷，烷基化类水滑石化合物属于阴离子型粘土‘’‘，其中心金属离子Ｍ２＋或Ｍ３＋及平衡阴离子可根据需要进行改变．...     

On directed diffusion with measurable background

We show that the ‘directed diffusion equation’ with periodic boundary conditions has a unique weak solution u whenever b is measurable and bounded above and below by positive constants. Also, lim_t→∞u(t,x) in L^p, 1?p≤∞.     

Crystal Structure and Catalytic Properties of Tetrakis（4-hydroxyphenyl）Porphyrinato Manganese （Ⅲ） Chloride （MnTHPPCI）

The crystal structure of meso-tetrakis （4-hydroxyphenyl） porphyrinato manganese chloride （MnTHPPC1） and its supramolecular architecture based on the hydrogen bonds of one counter C1 anion with four hydrogen atoms of four-OH groups from different MnTHPPC1 molecules cooperated by self-assembly of the porphyrin units were first repor-ted. This compound crystallized in the tetragonal space group 14/m with a = 1.39928（7） nm, b = 1.39928（7） nm, c =0.94498（10） nm, V= 1.8503（2） nm^3, and Z =2. As a catalyst, MnTHPPC1 also showed a high catalytic acti-vity in the conversion from 1-naphthylamine （1-NA） to his （4-oxo-benzo-2-cyclohexen-l-yl） amine （BOBCHA） v/a oxidative coupling under mild conditions.     

钨锗酸催化合成马来酸双酯

马来酸双酯与醋酸乙烯、苯乙烯、氯乙烯、丙烯酸酯等进行共聚,将可塑性基团直接接在分子链上,可起到内增塑的作用,也用作凝胶化促进剂、粘合剂原料、杀虫剂、杀菌剂和防锈添加剂等.杂多酸是一类性能优异的固体超强酸,广泛应用于催化领域。杂多酸催化化学进展迅速.本文研究钨锗杂多酸催化合成马来酸双酯.     

Two new α,β-unsaturated butyrolactone derivatives from Pleione bulbocodioides

Two newα,β-unsaturated butyrolactone derivatives,4-(4″-hydroxybenzyl)-3-(3′-hydroxy-phenethyl)furan-2(5H)-one(1)and 3-(3′-hydroxyphenethyl)furan-2(5H)-one(2),together with one known phenolic compound(3),were isolated from the tubers of Pleione bulbocodioides(Franch.)Rolfe.Their structures were elucidated by analysis of spectroscopic data.     

Survey on the Mechanical Properties of Lamellar Ag-MXA Supercluster Architectures

Lamellar nanomaterials with specific architectures and novel properties have received increasing attention from both scientific and technological fields in recent years because of their potential applications in catalysis, energy conversion, and storage devices. Bulk supercluster pellets with well-defined lamellar structures were fabricated by assembling silver clusters and mercaptoalkyl acids (MXA) to investigate the mechanical properties. The relationship between the assembled structure and pressure resistance was surveyed for the first time. The enhanced interlayer interactions were found to increase the elastic modulus of the Ag-MXA supercluster architectures.     

Passively Q-switched single-frequency output from a diffusion-bonded monolithic Nd:YAG non-planar ring oscillator

A compact monolithic Nd:YAG non-planar ring laser with diffusion-bonded Cr4+:YAG is demonstrated,and high stable pulsed single-frequency laser at 1.06 μm is realized.Theoretical analysis and simulation results of pulsed laser parameters are illustrated.14.96-kW maximum peak power,pulse-width of 4.8 ns is achieved for single-frequency operation.     

Global holomorphic 2-forms and pluricanonical systems on threefolds

The change of zero locus of a global holomorphic 2-form on a threefold under birational transformations is investigated. It is proved that existence of 2-forms with certain conditions on their zero loci on a threefold of nonnegative Kodaira dimension limits types of terminal singularities appearing on its minimal models. As a result of the restriction on the types of terminal singularities and Reid's Riemann-Roch formula, a universal bound N is found such that the linear system NK defines a birational map from a threefold of general type admitting those 2-forms, where K is the canonical bundle of the threefold. Received March 10, 2000 / Published online October 11, 2000     

Reactive blue 19 adsorption behaviors of magnesium hydroxide modified biochar derived from the traditional Chinese medical residual

This study examined the reactive blue 19 (RB-19) adsorption behaviors of magnesium hydroxide modified biochar (MBC) derived from the traditional Chinese medical residual. The obtained MBC was characterized using Scanning Electron Microscope (SEM), Fourier Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET). The static adsorption experiment was carried out to investigate the adsorption properties. The results indicated that pH 4 was best for the adsorption removal of RB-19 in the pH range of 4–9. Compared with the pseudo-first-order model and Elovich model, the pseudo-second-order equation was best to describe the adsorption process (R² > 0.995). The Langmuir model was better than the Freundlich model to fit the experimental data (R² > 0.990). The intra-particle diffusion model showed that film diffusion and intra-particle diffusion were involved in the adsorption process. Thermodynamic parameters showed that the RB-19 adsorption by MBC was spontaneous and endothermic. The adsorption mechanism might include electrostatic interaction, pore filling, and hydrogen bond, and the MBC was a promising adsorbent.