A tangent-plane marker-particle method for the computation of three-dimensional solid surfaces evolving by surface diffusion on a substrate

We introduce a marker-particle method for the computation of three-dimensional solid surface morphologies evolving by surface diffusion. The method does not use gridding of surfaces or numerical differentiation, and applies to surfaces with finite slopes and overhangs. We demonstrate the method by computing the evolution of perturbed cylindrical wires on a substrate. We show that computed growth rates at early times agree with those predicted by the linear stability analysis. Furthermore, when the marker particles are redistributed periodically to maintain even spacing, the method can follow breakup of the wire.     

Fe48Co52 Alloy Nanowire Arrays： Effects of Magnetic Field Annealing

The effects of magnetic field annealing on the properties of Fe48Co52 alloy nanowire arrays with various interwire distances （Di=30-60 nm） and wire diameters （Dw=22-46 nm） were investigated in detail. It was found that the array＇s best annealing temperature and crys- talline structure did not show any apparent dependence on the treatment of applying a 3 kOe magnetic field along the wire during the annealing process. For arrays with small Dw or with large Di, the treatment of magnetic field annealing also had no obvious influence on their magnetic performances. However, such a magnetic field annealing constrained the shift of the easy magnetization direction and improved the coercivity and the squareness obviously for arrays with large Dw or with small Di. The difference in the intensity of the effective anisotropic field within the arrays was believed to be responsible for this different variation of the array＇s magnetic properties after magnetic field annealing.     

交叉流聚丙烯中空纤维膜式氧合器的传质研究Ⅰ结构因子α、β的测定和氧合器传质效果评价

在膜式氧合器水气传递实验装置上分别对二种不同的交叉流微孔聚丙烯中空纤维膜式氧合器进行了水气传递实验，测得了氧合器的结构因子α、β，并用Ｍｏｃｋｒｏｓ和Ｌｅｏｎａｒｄ对Ｏ２传递建立的半经验数学模型拟合了血气传递实验中氧气在血中的传递速率。结果表明，理论计算与实验数据十分吻合，偏差小于１０％。讨论了α、β与膜式氧合器的传递效果的关系。     

Lagrangian approach for dark soliton in nonlocal nonlinear media

We theoretically investigate the dynamics of dark solitons as well as their interaction in nonlocal media. Approximate equations describing the evolution of the beams are obtained via suitable trial functions of amplitude u and refractive index n in an averaged Lagrangian. Our results reveal that out-of-phase dark solitons can evolve into stable bound states in nonlocal materials. Moreover, it is found that the separations in the bound state monotonically increase with the degree of nonlocality in nonlocal limit. These results are in excellent agreement with the numerical simulations.     

A Novel Nanoparticle‐Based Disposable Electrochemical Immunosensor for Diagnosis of Exposure to Toxic Organophosphorus Agents

A novel disposable electrochemical immunosensor for highly selective and sensitive detection of organophosphorylated butyrylcholinesterase (OP‐BChE), a specific biomarker for exposure to toxic organophosphorus agents, is presented. In this new approach, zirconia nanoparticles (ZrO₂) were employed to selectively capture the OP moiety of OP‐BChE adducts, followed by quantum dot (QD)‐tagged anti‐BChE antibodies for amplified quantification. The captured CdSe‐QD tags can be sensitively detected by stripping voltammetry using an in situ bismuth‐plating method. The OP agent, diisopropylfluorophosphate (DFP), was selected to prepare OP‐BChE adducts in various matrices. The formation of OP‐BChE adducts in plasma sample was confirmed using mass spectroscopy. The developed electrochemical immunosensor demonstrates a highly linear voltammetric response over the range of 0.1 to 30 nM OP‐BChE, with a detection limit of 0.03 nM (based on signal/noise = 3), coupled with a good reproducibility (relative standard deviation 4.5%). Moreover, the immunosensor has been validated with biomonitoring of OP‐BChE adducts in the plasma samples. This novel nanoparticle‐based electrochemical immunosensor thus provides an alternative way for designing a sensitive and cost‐effective sensing platform for on‐site screening/evaluating exposure to a variety of OP agents.     

浅析门户式数字图书馆资源与服务的技术实现

门户式数字图书馆是一种新兴的数据库资源管理模式,其目的在于解决分布式异构数据库资源的"孤岛"问题,实现分布式数据库资源的整合与统一检索,本文对门户式数字图书馆的用户界面设计、资源与服务布局以及层次结构进行了剖析,提出数字图书馆的建设标准和技术要求。     

Effects of Surfactant and Salt Species in Reverse Micellar Forward Extraction Efficiency of Isoflavones with Enriched Protein from Soy Flour

Suitability of reverse micelles of anionic surfactant sodium bis(2-ethyl hexyl) sulfosuccinate (AOT) and sodium dodecyl sulfate (SDS), cationic surfactant hexadecyl trimethyl ammonium bromide (CTAB) and nonionic surfactant polyoxyethylene p-t-octylphenol (TritonX-100) in organic solvent isooctane for extraction of soy isoflavone-enriching proteins was investigated. The results showed that the order of combined isoflavone contents was SDS>CTAB>Triton X-100>AOT, while the order of protein recovery was SDS>AOT>TritonX-100>CTAB. As compared with ACN-HCl extraction, the total amount of isoflavones was lower than reverse micellar extraction. Ion strength was one of the important conditions to control extraction of isoflavone-enriching proteins with AOT reversed micelles. For the six salt systems, KNO₃, KCl, MgCl₂, CaCl₂, NaCl, and Na₂SO₄, extracted fraction of isoflavone-enriching proteins was measured. Salt solutions greatly influenced the extraction efficiency of isoflavones in an order of KNO₃>MgCl₂>CaCl₂>KCl>NaCl>Na₂SO₄, while protein in an order of MgCl₂>CaCl₂>NaCl>KNO₃>Na₂SO₄>KCl.