An Integrated Two Phases Approach to Zn2+ Ions Electroreduction on Hg

The following two numerical models have been applied to zinc cations electroreduction in 1 M NaClO₄ water solution: a classical EE model describing the concentration of involved species in solution (semi infinitive diffusion region), an extended EE model describing both: the concentration of involved species in solution and the concentration of metallic zinc inside mercury drop (in limited area of diffusion). In the latter model the inner part of mercury drop and surrounding solution were treated as dynamic interrelated system. Both models were applied to experimental cyclic voltammetric CV data in 1 M NaClO₄, the results compared and discussed. The concentration profiles of all species including metallic zinc inside mercury drop were performed. The presented integrated model is essential for theoretical and analytical aspects of the electrochemistry of mercury soluble metal cations and amalgams.     

一种基于J2EE服务器集群的中间件负载平衡系统

基于中间件的负载平衡服务是为J2EE服务器集群提供高可用性和高伸缩性的一种有效方法,针对目前的J2EE服务器集群负载平衡服务还存在客户端和服务器端透明性差、负载平衡策略简单和无自适应能力等缺陷,设计了一种基于J2EE服务器集群的中间件负载平衡系统-JCLBS,较好地解决了上述问题。     

Square‐wave Voltammetry of Two‐step Surface Electrode Mechanisms Coupled with Chemical Reactions – A Theoretical Overview

Square‐wave voltammetry (SWV) of so‐called “surface redox reactions” is seen as a simple and efficient tool to quantify large number of drugs, physiologically active substances and other important chemicals. It also provides elegant methods to get access to relevant kinetic and thermodynamic parameters related to many lipophilic compounds. Moreover, with this technique we can study activity of various enzymes by exploring the “protein‐film voltammetry” set up. In this work, we focus on theoretical SWV features of four complex surface electrode mechanisms, in which the electron exchange between the working electrode and the studied redox substrate takes place in two successive steps. While we present large number of calculated square‐wave voltammograms, we give hints to recognize particular two‐step surface mechanism, but also to distinguish it from other similar mechanisms. We present plenty of relevant aspects of surface two‐step surface EE, two‐step surface ECE and surface catalytic EEC’ mechanisms. Moreover, we present for the first time a series of theoretical results related to two‐step surface EECrev mechanism (i. e. two‐step surface reaction coupled to follow‐up reversible chemical step). The simulated voltammetric patterns presented in this work can bring relevant aspects to resolve some experimental situations met in voltammetry of many redox enzymes and other important substances whose electrochemical transformation occurs in two‐steps.     

基于Socket通信的工业机器人监控系统研究

针对Epson-G6和Staubli-TX90工业机器人,研究一种基于Socket通信的工业机器人监控系统。系统分为本地监控端和Web远程监控端。基于TCP协议和Socket通信技术,编写了机器人控制器服务端程序和MFC类库开发的客户端程序,客户端分为通讯功能模块,末端坐标轨迹存储模块和基于OpenGL类库的运动姿态展现模块。在此基础上, 基于J2EE架构和WebSocket通信协议编写了Web远程监控端程序,分为用户管理模块和实时监控模块。系统实现了机器人末端坐标轨迹的采集并远程存储至PostgreSQL数据库,同时通过逆运动学计算展现了机器人三维运动姿态,并在Web页面以动态曲线方式监控机器人的末端坐标轨迹。     

Monitoring of progestins: Development of immunochemical methods for purification and detection of levonorgestrel

A polyclonal antibody (Ab) for the progestin levonorgestrel (LNG) was generated, and immunochemical assays for its detection, clean-up and concentration were developed. A highly specific microplate diagnostic assay for the detection of LNG was developed that used the enzyme linked immunosorbent assay (ELISA) method. The LNG ELISA developed was sensitive and reproducible; it exhibited I₅₀ and I₂₀ values of 3.3 ± 1.8 ng mL⁻¹ and 0.6 ± 0.4 ng mL⁻¹, respectively, and the Abs did not cross react with any of the tested steroid hormones. The above Abs were used to develop a sol-gel-based immunoaffinity purification (IAP) method for concentration and clean-up of LNG that is compatible with subsequent immunochemical or instrumental chemical analytical procedures, such as liquid chromatography followed by mass spectrometry (LC-MS/MS). Development of the columns included successful entrapment of Abs within a tetramethoxysilane (TMOS)-based SiO₂ polymer network. The Abs could bind the free analyte from solution, and the bound analyte could be easily eluted from the sol-gel matrix at high recoveries. The Ab selectivity towards the antigen was high, in both ELISA and the sol-gel columns, but the entrapped Abs cross-reacted with two other steroid hormones - ethynylestradiol (EE2) and nortestosterone (NT) - which share similar epitopes with LNG, despite the lack of cross reactivity in the ELISA. The validity of the method was investigated by LC-MS/MS and a good analytical correlation was obtained.     

Effect of the γ-radiation on phenol fractions obtained from the leaves of Echinodorus macrophyllus Mich.

Echinodorus macrophyllus Mich. (Chapéu-de-couro) is popularly used as diuretic, anti-arrhythmic, anti-inflammatory, and anti-rheumatic agents. Leaves of this species are largely commercialized and show high level of microbiological contamination (bacteria and fungi). This work describes the effect of the ⁶⁰Co γ-radiation on the phenol fractions obtained from the leaves of E. macrophyllus. trans-Ferulic acid, (E)-caffeoyltartronic acid, 6-C-(1-hexitol)-apigenin, and 6-C-(1-hexitol)-luteolin were isolated by preparative HPLC. HPLC chromatograms showed concentration changes of some phenolic constituents, suggesting the formation of radiolytic products. The phenol fractions were active against Bacillus subitilis and Staphylococcus aureus and showed high antioxidant activity. However, the antibacterial and antioxidant activities reduced when the absorbed dose was increased.     

A rare ferromagnetically coupled asymmetric doubly azido bridged copper(II) dimer with an N,N, O donor Schiff base

A new end-to-end (EE) doubly azido bridged dinuclear complex [Cu₂L₂(μ_1,3-N₃)₂] (1) [where L = (E)-4-(2-(dimethylamino)ethylimino)-1,1,1-trifluoropentan-2-one)] has been synthesized and characterized by elemental and spectroscopic techniques. Single crystal X-ray diffraction analysis reveals that the dimeric complex possesses a center of inversion. Each copper atom in 1 is in a distorted square pyramidal geometry with a CuN₄O chromophore as revealed from the τ value, 0.19. The four basal positions are occupied by two imine N and one keto O atom of the Schiff base and one N atom from the azide anion. Another N atom from a coordinated azide occupies the apical position. Temperature dependent magnetic susceptibility of 1 was fitted using the Bleaney–Bowers expression which led to the parameters J = 13.6 cm⁻¹ and R = 3.4 × 10⁻⁵. It indicates a ferromagnetic interaction through the double azido bridges connecting the individual copper Schiff base units.     

Enhanced generalized space shift keying with search field based iterative MLD for 6G

This paper proposes the novel enhanced generalized space shift keying (EGSSK) to improve the spectral efficiency (SE) and energy efficiency (EE). In conventional GSSK, all of antenna combinations are not used because of power-of-two form. To overcome this problem, we suggest to exploit spare antenna combination for cell-edge users (CEUs). Concurrently, we propose the search field based iterative maximum likelihood detector (SFMLD) to reduce the complexity at the receiver. The simulated and analytical results are shown in terms of SE, average bit error rate (ABER), complexity and EE.     

Numerical Modeling of ECE‐ECE and Parallel EE‐EE Mechanisms in Cyclic Voltammetry. Reduction of 1,4‐Benzenedisulfonyl Difluoride and 1,4‐Naphthalenedisulfonyl Difluoride

A numerical model of the process where the ECE‐ECE sequence competes with the parallel EE‐EE mechanisms of reduction has been developed. The ECE‐ECE / EE‐EE model was applied to complex, experimentally observed processes, in which the parallel path of anion‐radical reduction could be expected. The applicability of the proposed model was examined experimentally for two chemical systems: (i) 1,4‐benzenedisulfonyl difluoride (1,4‐BDF) and (ii) 1,4‐naphthalenedisulfonyl difluoride (1,4‐NDF). For both model compounds the reduction processes on Hg and glassy carbon electrodes were investigated by means of cyclic voltammetry performed in DMF solutions containing 0.3 M of TBAP. In contrast to other reductive cleavage reactions such as the fragmentation of the C‐Hal–type bond, the electro‐reduction of anion‐radicals ArSO₂F^?. was evident. The elementary kinetic parameters of the process are determined and discussed.     

Synthesis and application on parallel image storage of bisfurylfulgide

The synthesis of photochromic compounds has received a great deal of attention because of their potential application in various areas such as optical information storage[1—5], photoswitches and molecular recognition[6—8]. One of the most important researches in this field is the synthesis of a variety of photochromic fulgides to establish basic correlation between their molecular structures and photochromic properties. Since 1978, Heller[9] firstly reported the synthesis of the heterocyclic…