N, N''－双［(1－苯基－3－甲基－5－氧－4－吡唑啉基)亚苄基］乙二亚胺萃取钯的机理及钯－铂体系中钯的选择性萃取

本文首次报道了标题试剂Ｈ２Ａ对钯的萃取行为，确定了萃取物的组成，讨论了萃取机理，算出了萃取平衡常数，通过化学分析、红外及拉曼光谱，紫外光谱，研究得出了萃合物的结构，并且实现了Ｈ２Ａ从钯－铂混合溶液中选择性萃钯。     

Modeling Study on the Entrainment of Ambient Air into Subsonic Laminar and Turbulent Argon Plasma Jets

Modeling study is performed to reveal the special features of the entrainment of ambient air into subsonic laminar and turbulent argon plasma jets. Two different types of jet flows are considered, i.e., the argon plasma jet is impinging normally upon a flat substrate located in atmospheric air surroundings or is freely issuing into the ambient air. It is found that the existence of the substrate not only changes the plasma temperature, velocity and species concentration distributions in the near-substrate region, but also significantly enhances the mass flow rate of the ambient air entrained into the jet due to the additional contribution to the gas entrainment of the wall jet formed along the substrate surface. The fraction of the additional entrainment of the wall jet in the total entrained-air flow rate is especially high for the laminar impinging plasma jet and for the case with shorter substrate standoff distances. Similarly to the case of cold-gas free jets, the maximum mass flow-rate of ambient gas entrained into the turbulent impinging or free plasma jet is approximately directly proportional to the mass flow rate at the jet inlet. The maximum mass flow-rate of ambient gas entrained into the laminar impinging plasma jet slightly increases with increasing jet-inlet velocity but decreases with increasing jet-inlet temperature.     

广义簇合物在非均匀几率密度下的生长

采用族合物生长的自调整模型，并用扩散粒子的非均匀几率密度场模拟了簇合物和扩散粒子之间的非均匀相互作用势场,研究了广义簇合物在非均匀场下的生长形态，考察了深度因子α、粘附参数t等对簇合物生长形态及对非均匀场的影响，结果表明，非均匀场的性质是决定族合物生长几何形态的主要因素，深度因子α决定了簇合物中生长形态的紧密程度，粘附参数t决定了致密程度，α、t等参数对场的作用有一定的影响     

[Cu(dien)Cl]+与DNA及多核苷酸作用的平衡透析研究

用平衡透析法研究了37℃、pH=6.00,离子强度为0.005条件下的[Cu(dien)Cl]~+与DNA、多聚腺苷酸、多聚鸟苷酸以及多聚胞苷酸之间的相互作用。用McGhee和von Hippel法对实验数据进行了分析,求得其结合常数、反映键合过程中(Cu(dien)Cl]~+间相互作用的协同参数以及每个[Cu(dien)Cl]~+所键合的核苷酸残基数。     

Dual pH and glucose sensitive gel gated mesoporous silica nanoparticles for drug delivery

A low-molecular-weight gel with dual pH and glucose sensitivity was designed as the gate controller for mesoporous silica nanoparticles (MSNs) to fabricate a smart drug delivery system. The smart gel caped MSNs could control the antidiabetic drug release via the detection of glucose and pH levels.     

Comparison of Laminar and Turbulent Thermal Plasma Jet Characteristics—A Modeling Study

Modeling results are presented to compare the characteristics of laminar and turbulent argon thermal plasma jets issuing into ambient air. The combined-diffusion-coefficient method and the turbulence-enhanced combined-diffusion-coefficient method are employed to treat the diffusion of ambient air into the laminar and turbulent argon plasma jects, respectively. It is shown that since only the molecular diffusion mechanism is involved in the laminar plasma jet, the mass flow rate of ambient air entrained into the laminar plasma jet is comparatively small and less dependent on the jet inlet velocity. On the other hand, since turbulent transport mechanism is dominant in the turbulent plasma jet, the entrainment rate of ambient air into the turbulent plasma jet is about one order of magnitude larger and almost directly proportional to the jet inlet velocity. As a result, the characteristics of laminar plasma jets are quite different from those of turbulent plasma jets. The length of the high-temperature region of the laminar plasma jet is much longer and increases notably with increasing jet inlet velocity or inlet temperature, while the length of the high-temperature region of the turbulent plasma jet is short and less influenced by the jet inlet velocity or inlet temperature. The predicted results are reasonably consistent with available experimental observation by using a DC arc plasma torch at arc currents 80–250 A and argon flow rates (1.8–7.0)×10⁻⁴ kg/s.     

Dynamics of Hollow Nanofiber Formation During Solidification Subjected to Solvent Evaporation

Summary: To mimic the emergence of gradient morphology in polymer nanofibers, a new theoretical approach has been developed in the context of Cahn‐Hilliard time evolution equation, alternatively known as time‐dependent Ginzburg‐Landau equation (Model B) involving concentration order parameter. The effects of solvent evaporation on the morphology evolution of the nanofibers have been demonstrated. The numerical simulation showed that the formation of skin layers is governed by the competition between solvent evaporation rate and mutual diffusion rate. That is to say the skin layers are formed in the nanotube whenever the rate of evaporation exceeds a critical value; otherwise, a solid fiber is formed. In hollow nanofibers, the layer can grow to a substantial fraction of the fiber diameter, allowing it to remain intact, albeit often in a collapsed form.

The cross‐sectional concentration profile of the emerging fiber.     

Conformational Studies on Pentagastrin by 2D NMR and Restrained Molecular Dynamics

The present study uses 2D NMR to assign all resonance lines of pentagastrin completely. From 2D NOESY and coupling constants J_HNα, interproton distance and torsion angle Φ restraints were obtained. Based on them, the model of conformation for pentagastrin was proposed by restrained molecular dynamics calculation. It is shown that the C-terminal part of pentagastrin forms a Δ turn with a weak H-bond between the CO of Met and the NH of Phe. A strong H-bond between indole NH of Trp and β-carboxyl group of Asp stablizes the folded form in DMSO, which may result in a significant increase in the population of a favorable conformation for interaction with receptor.     

1H NMR Saturation Transfer Studies of Exogenous Ligands Binding to Metmyoglobin

Two-dimensional(2D) ¹H. nuclear magnetic resonance exchange spectroscopy, 1D saturation transfer have been utilized to study the binding of imidazole(lm), 1-Methylimidazole(Melm), 1-Ethylimidazole(Etlm) to the heme iron of metmyoglobin. Some heme peripheral proton resonance's of these complexes have been first time assigned. The rates and equilibrium constants for Im, Melrn, Etlm binding to metMb are calculated from the 2D peak amplitudes. Analysis of the heme methyl shifts indicates that the orientations of the binding Im, Melm, Etlm are very similar. The steric effects and hydrogen bonding between the distal histidine and bound ligand are important factors regulating affinity.