Photodiode Circuit Macro-model for SPICE Simulation

An accurate photodiode circuit macro-model is proposed for SPICE simulation. The definition and implementation of the macro-model is based on carrier stationary continuity equation. In this macro-model, the photodiode is a device of three pins, one for light intensity input and the other two for photocurrent output, which represent the relationship between photocurrent and incident light. The validity of the proposed macro-model is demonstrated with its PSPICE simulation result compared with reported experimental data.     

网络入侵防御系统高可用性研究

本文分析了NIPS实用化面临的诸多挑战,给出了一些提高NIPS可用性的设计原则,并在简单比较了两种常 用NIPS硬件平台,即网络处理器和专用集成电路的特性后,给出了一种基于网络处理器、负载平衡器和IDS集群的NIPS 框架结构设计。     

E_m函数类中Nevanlinna-Pick插值与广义Stieltjes矩量问题

令E\-m=(-∞,∞)＼∪[DD(]m[]j=1[DD)](α\-j,β\-j).函数类[WTHT]N[WTBX](E\-m)表示在上半复平面解析且虚部非负,在诸(α\-j,β\-j)(j=1,…,m)内解析且为实值的函数全体.该文用Hankel 向量方法建立[WTHT]N[WTBX](E\-m)函数类 中含有限(或无限可数)插值点的Nevanlinna Pick 问题与集合E\-m上 相关的非标准截断(或全)广义Stieltjes 矩量问题解集之间的一一对应.用类似于Riesz的办法建立E\-m上非标准截断广义Stieltjes矩量问题的可解性准则,从而获得了[WTHT]N[WTBX](E\-m)函数类中Nevanlinna Pick问题的可解性准则.     

利用网络处理器构建弹性分组环模块

弹性分组环作为解决城域网的问题的一个方案被提出后,迅速成为研究的热点,但专用的RPR芯片还未商品化。提出了一种利用不支持RPR协议的网络处理器借助协议转换器来构建RPR模块的设计方案。协议转换器的主要功能是RPR/Ethernet帧转换和接口转换。文章介绍了RPR模块的结构和功能,并讨论了协议转换器的实现。     

Three theorems regarding testing graph properties

Property testing is a relaxation of decision problems in which it is required to distinguish YES ‐instances (i.e., objects having a predetermined property) from instances that are far from any YES ‐instance. We presents three theorems regarding testing graph properties in the adjacency matrix representation. More specifically, these theorems relate to the project of characterizing graph properties according to the complexity of testing them (in the adjacency matrix representation). The first theorem is that there exist monotone graph properties in ???? for which testing is very hard (i.e., requires to examine a constant fraction of the entries in the matrix). The second theorem is that every graph property that can be tested making a number of queries that is independent of the size of the graph can be so tested by uniformly selecting a set of vertices and accepting iff the induced subgraph has some fixed graph property (which is not necessarily the same as the one being tested). The third theorem refers to the framework of graph partition problems, and is a characterization of the subclass of properties that can be tested using a one‐sided error tester making a number of queries that is independent of the size of the graph. © 2003 Wiley Periodicals, Inc. Random Struct. Alg., 23: 23–57, 2003     

Fabrication of Ag nanoparticle/ZnO thin films using dual-plasma-enhanced metal-organic chemical vapor deposition (DPEMOCVD) system incorporated with photoreduction method and its application

We report a novel method to grow silver nanoparticle/zinc oxide (Ag NP/ZnO) thin films using a dual-plasma-enhanced metal-organic chemical vapor deposition (DPEMOCVD) system incorporated with a photoreduction method. The crystalline quality, optical properties, and electrical characteristics of Ag NP/ZnO thin films depend on the AgNO₃ concentration or Ag content and annealing temperature. Optimal Ag NP/ZnO thin films have been grown with a AgNO₃ concentration of 0.12 M or 2.54 at%- Ag content and 500 °C- rapid thermal annealing (RTA); these films show orientation peaks of hexagonal-wurtzite-structured ZnO (002) and face-center-cubic-crystalline Ag (111), respectively. The transmittance and resistivity for optimal Ag NP/ZnO thin films are 85% and 6.9×10⁻⁴ Ω cm. Some Ag NP/ZnO transparent conducting oxide (TCO) films were applied to InGaN/GaN LEDs as transparent conductive layers. The InGaN/GaN LEDs with optimal Ag NP/ZnO TCO films showed electric and optical performance levels similar to those of devices fabricated with indium tin oxide.     

Quaternized Silicon Nanoparticles with Polarity‐Sensitive Fluorescence for Selectively Imaging and Killing Gram‐Positive Bacteria

With the emergence of antibiotic resistance, developing new antibiotics and therapies for combating bacterial infections is urgently needed. Herein, a series of quaternized fluorescent silicon nanoparticles (SiNPs) are facilely prepared by the covalent reaction between amine‐functionalized SiNPs and carboxyl‐containing N‐alkyl betaines. It is found that the bactericidal efficacy of these quaternized SiNPs increases with the length of the N‐alkyl chain, and SiNPs conjugated with N,N‐dimethyl‐N‐octadecylbetaine (BS‐18), abbreviated as SiNPs‐C₁₈, show the best antibacterial effect, whose minimum inhibitory concentrations for Gram‐positive bacteria are 1–2 μg mL^?1. In vivo tests further confirm that SiNPs‐C₁₈ have excellent antibacterial efficacy and greatly reduce bacterial load in the infectious sites. The SiNPs‐C₁₈ exhibit low cytotoxicity toward mammalian cells (including normal liver and lung cells, red blood cells, and macrophages), enabling them to be useful for clinical applications. Besides, the quaternized SiNPs exhibit polarity‐dependent fluorescence emission property and can selectively image Gram‐positive bacteria, thereby providing a simple method to successfully differentiate Gram‐positive and Gram‐negative bacteria. The present work represents the first example that successfully turns fluorescent SiNPs into metal‐free NP‐based antibiotics with simultaneous bacterial imaging and killing capability, which broadens the applications of fluorescent SiNPs and advances the development of novel antibacterial agents.     

New potential anti-SARS-CoV-2 and anti-cancer therapies of chitosan derivatives and its nanoparticles: Preparation and characterization

Chitosan (CS) is a biopolymer and has reactive amine/hydroxyl groups facilitated its modifications. The purpose of this study is improvement of (CS) physicochemical properties and its capabilities as antiviral and antitumor through modification with 1-(2-oxoindolin-3-ylidene)thiosemicarbazide (3A) or 1-(5-fluoro-2-oxoindolin-3-ylidene)thiosemicarbazide (3B) via crosslinking of poly(ethylene glycol)diglycidylether (PEGDGE) using microwave-assisted as green technique gives (CS-I) and (CS-II) derivatives. However, (CS) derivatives nanoparticles (CS-I NPs) and (CS-II NPs) are synthesized via ionic gelation technique using sodium tripolyphosphate (TPP). Structures of new (CS) derivatives are characterized using different tools. The anticancer, antiviral efficiencies and molecular docking of (CS) and its derivatives are assayed. (CS) derivatives and its nanoparticles show enhancement in cell inhibition toward (HepG-2 and MCF-7) cancer cells in comparison with (CS). (CS-II NPs) reveals the lowest IC₅₀ values are 92.70 ± 2.64 μg/mL and 12.64 µ g/mL against (HepG-2) cell and SARS-CoV-2 (COVID-19) respectively and the best binding affinity toward corona virus protease receptor (PDB ID 6LU7) ?5.71 kcal / mol. Furthermore, (CS-I NPs) shows the lowest cell viability% 14.31 ± 1.48 % and the best binding affinity ?9.98 kcal/moL against (MCF-7) cell and receptor (PDB ID 1Z11) respectively. Results of this study demonstrated that (CS) derivatives and its nanoparticles could be potentially employed for biomedical applications.     

辨微识源: 纳米颗粒物溯源技术的新进展※

随着纳米技术在医药、工业催化、食品及农业生产等领域的广泛应用, 人造纳米颗粒被大量生产并最终不可避免地进入自然环境, 进而造成潜在的环境和健康风险. 目前, 纳米材料已经被认为是一类潜在的环境污染物. 准确示踪纳米颗粒的来源和环境转化过程是评价其毒理学效应和进行精准污染管控的重要前提. 综述了近年来纳米颗粒溯源技术的新进展, 包括多维化学指纹技术、非传统稳定同位素技术、同位素标记技术和环境DNA标记技术等, 并对纳米颗粒溯源技术的未来发展方向进行了展望.     

Application of magnetic and core–shell nanoparticles to determine enrofloxacin and its metabolite using laser induced fluorescence microscope

A unique analytical method using nanoparticles and laser-induced fluorescence microscopy (LIFM) was developed to determine enrofloxacin in this work. For sample pretreatment, two different kinds of particles, i.e., synthesized dye-doped core–shell silica nanoparticles and magnetic micro-particles (MPs), were used for fluorescent tagging and concentrating the enrofloxacin, respectively. The antibody of enrofloxacin was immobilized on the synthesized FITC-doped core–shell nanoparticles, and the enrofloxacin target was extracted by the MPs. At this moment, the average number of antibodies on each core–shell silica nanoparticle was ∼0.9, which was determined by the fluorescence ratiometric method. The described method was demonstrated for a meat sample to determine enrofloxacin using LIFM, and the result was compared with enzyme-linked immunosorbent assay (ELISA). The developed technique allowed the simplified analytical procedure, improved the detection limit about 54-fold compared to ELISA.