A straightforward and environmentally benign method for the synthesis of silver nanoparticles (AgNPs) is reported in this paper. A sustainable and nontoxic polysaccharide carboxy methyl cellulose (CMC) was used as both reducing agent and stabilizer in the process of synthesizing AgNPs. By varying the precursor concentration, solution pH value, reaction temperature and duration, the highly stable and smaller sized AgNPs with narrow size distribution were obtained. The as-synthesized AgNPs were characterized using UV–Vis absorption spectroscopy, high resolution transmission electron microscopy, X-ray diffraction and zeta potential and size analyzer. Measurements of optical spectra showed that the surface plasmon resonance was localized around 404 nm. The TEM images showed that the particles are well dispersed and spherical in shape with an average particle diameter of 11.64 ± 2.32 nm which is less than the value (13.12 ± 1.54 nm) measured by dynamic light scattering. The zeta potential value of AgNPs was measured to be − 62.8 mV which indicated that CMC coated on the surface of as-synthesized AgNPs resulting in the negatively charged surface and the stable in nature. The prepared silver nanoparticles are effective in inhibiting the growth of both gram positive Staphylococcus aureus and gram negative Escherichia coli.

As a core part of the training program, graduation design plays an irreplaceable role in cultivating the ability of students to independently analyze and solve problems as well as enhancing students' comprehensive ability and professionalism. The current situation of graduation design quality for Material Chemistry specialty was analyzed from three aspects of students, instructors and security system. In order to improve the quality of undergraduate graduation design, four suggestions of attaching importance to preparatory work, optimizing time arrangement, strengthening the leading role of instructor and establishing reliable guarantee system were put forward.

研究生党支部是高校思想政治工作的重要阵地,其设置模式直接影响支部战斗堡垒作用的发挥.本文探讨了研究生党支部传统建设模式和工科学院研究生纵向党支部建设模式的利弊,并就如何增强工科学院研究生纵向党支部影响力提出了对策和建议.

The green synthesis of gold nanoparticles, using carboxymethyl cellulose as both capping agents and reducing agents, is an environmental friendly, simple and efficient route for synthesis of metallic nanoparticles. The optimal conditions, such as the ratio of 0.5 mM HAuCl4 against 0.4% CMC; temperature 80 °C; solution pH 9.0 and reaction duration 50 min, were established to produce the narrower distribution, the smaller and more stable AuNPs-CMC. The spherical gold nanoparticles-carboxymethyl cellulose nanocomposites (AuNPs-CMC) with an average particle size of 20.3 ± 5.5 nm was confirmed by the techniques such as high transmission electron microscopy, energy dispersive X-ray spectroscopy, selected area electron diffraction pattern and dynamic light scattering. The as-synthesized AuNPs-CMC with a SPR absorption band of 522 nm can be used as fluorescent probes for the detection of Hg(II) in the range of 0.05–0.32 μM with a detection limit of 3.6 nM. This study essentially paves the way for the generation of functional materials with coupled optical properties and as an analytical platform for rapid and selective detection of metal ions.

The bell-less top charging system is widely used for the blast furnace in ironmaking industry .As a critical component of the bell-less top charging system , the central throat has long been under the effection of impact abrasion and high temperature erosion .Firstly, the 3D model of the central throat was established , and the static mechanical analysis was performed by using the finite element software .Secondly , the static mechani-cal analysis results employed as the boundary conditions , the thermal-structural coupling analysis of the central throat was carried out .The analysis result illustrates that there is stress concentration around the corner of the upper part of the central throat .After structural improvements , the thermal stress is effectively reduced , and the impact abrasion and high temperature erosion of the central throat were declined too .

为了解决传统标定过程中标定困难、标定精度不高等难题,基于六自由度机器人面向带有旋转特征的曲面零件,提出一种八点标定方法.该方法利用带有旋转特征这一特点,准确找到工件坐标系原点,从而提高了标定精度.该方法通过实例论证,可以对带有旋转曲面特征的零件坐标系进行标定.使用该方法进行标定可以提高曲面工件坐标系与机器人坐标系匹配精度.

In the era of knowledge-driven economy, independent talents are urgently needed. Colleges and universities shoulder the unshirkable responsibility in developing independent talents. In this paper, current problems of culturing independent talents in colleges and universities will be analysed from the perspective of material subject. Methods in developing independent talents will be discussed from the scopes of following the basic rules of developing talents, enriching teaching methods, introducing group discussion, letting cultivation of innovative ability go through the whole educative process and attaching importance to the power of role models.

Palladium nanoparticles (PdNPs) were synthesized through friendly environmental method using PdCl2 and carboxymethyl cellulose (CMC) in an aqueous solution (pH 6) at controlled water bath (80 degrees C) for 30 min. CMC functioned as both reducing and stabilizing agent. The characterization through high resolution-transmission electron microscopic (HRTEM) and X-ray Fluorescence Spectrometry (XRF) inferred that the as-synthesized PdNPs were spherical in shape with a face cubic crystal (FCC) structure. The results from dynamic light scattering (DLS) suggested the PdNPs had the narrow size distribution with an average size of 2.5 nm. The negative zeta potential (-52.6 mV) kept the as-synthesized PdNPs stable more than one year. The PdNPs showed the excellent catalytic activity by reducing degradation of azo-dyes, such as p-Aminoazobenzene, acid red 66, acid orange 7, scarlet 3G and reactive yellow 179, in the present of sodium borohydride. (C) 2016 Elsevier B.V. All rights reserved.

Chromium(VI) is one of the forbidden heavy metals in the ecological textiles. It is vitally important to develop methods for the sensitive and selective detection of CAD in textile samples. In this work, gold nano particles -sodium alginate clusters (AuNPs-SA) was prepared with sodium alginate in one-step synthesis route and its fluorescent property was investigated. The strongest fluorescence intensity of AuNPs-SA clusters located at the max emission wavelength lambda(em) =415 nm under the excitation wavelength of lambda(em) =360 nm. A fluorimetric method was developed based on the fluorescent AuNPs-SA nanocomposites selectively quenched in the presence of Cr(VI). The possible quenching mechanism was discussed on the basis of the interaction of positive AuNPs-SA with negative Cr (VI). Under the optimized experimental conditions, The ratiometric fluorescence was linearly proportional to the concentration of CAD ranging from 1.0x10(-8) moUL to 9.0x10(-8) moUL. The limit of determination (LOD) was estimated at 5.0 x10(-9) moUL based on the regression calculations. This method was used for the determination of chromium (VI) in textile samples, and the obtained result had no significant difference compare to the results based on the National Standard of the People's Republic of China (GB/T 17593.3-2006)

新时期,随着高校研究生扩招、教育体制改革以及网络新媒体快速发展等环境的变化,高校研究生党员的价值取向和研究生党支部的组织建设随之发生了改变,研究生党建凝聚力建设工作面临新机遇和挑战.本文对新时期高校研究生党支部凝聚力建设与运行过程中出现的问题进行了初步分析与探讨,结合我校多年党建工作经验,从基层党组织制度建设、组织生活建设等方面做出了对策研究,为增强高校研究生党支部的创造力、凝聚力和战斗力提供助力.

A green synthesis of gold nanoparticles (AuNPs) using aqueous solution of sodium alginate (SA) has been demonstrated in this work. The SA plays the roles of both reducing and stabilizing agent. The surface plasmon resonance (SPR) band of UV-Vis spectrum around 532[Formula: see text]nm confirmed the formation of AuNPs. The characterization through high resolution-transmission electron microscopic (HRTEM), energy dispersive X-ray (EDX) spectroscopy and X-ray diffraction (XRD) infer the as-synthesized AuNPs which were spherical in shape with a face cubic crystal (FCC) structure. The results obtained from zeta potential and dynamic light scattering (DLS) suggest the good stability and narrow size distribution of the AuNPs. The size-controlled AuNPs were obtained through adjusting the reaction parameters such as the concentration of SA, pH of the reaction mixture, temperature and the time of incubation. The as-synthesized AuNPs–SA conjugates were employed to prepare AuNPs–SA beads easily based on SA high affinity toward divalent metal ions. The resulting AuNPs–SA beads function as an efficient heterogeneous catalyst in reducing decoloration of azo-dye model compounds, acidic orange 7 (AO7) and reactive orange 5 (RO5), in the presence of sodium borohydride. The reaction rate constants, estimated based on the reduction reactions followed pseudo-first-order kinetics, suggest the high catalytic activity and stability of the AuNPs–SA beads.

研究生党支部建设是研究生思想政治教育的重要环节,是高层次人才培养的重要抓手.针对当前高校研究生党支部普遍存在的凝聚力弱化同题,本文探讨了影响研究生党支部凝聚力的因素,并从完善机制、学习教育和活动开展三个方面提出了提高研究生党支部凝聚力的创新机制.

创新型企业和人才是创新型产业集群的主体,培育创新型企业和人才是发展创新型产业集群的基础手段.本文在阐述创新型产业集群的内涵与特征基础上,分析了创新型产业集群发展过程中人才支撑的重要意义,给出了促进创新型产业集群发展的人才支撑对策.

China locates at the region of water shortage, domestic water environment pollution is getting worse, so water-saving and wa-ter-reuse is crucial. Water supply and drainage system includes water supply system, greywater system and drainage system, as an important part of the construction project. A series of corresponding laws and regulations should be issued to strengthen daily management and propa-ganda. The water supply and drainage engineering is expounded on its strategic significance of water-saving and energy-saving. The existing difficulties are researched from multi-angle perspective, as well as architectural energy-saving technical measures.

文中通过对我国高校后勤水电管理模式、存在的问题进行了分析,认为通过水电指标定额目标管理,能有效解决高校水电被动管理的局面,同时认为通过不断的摸索,在高校水电指标制定过程中,能探索出比较合适的科学制定办法,最终达到节约能源的目的。

With the continuous development of science and technology and the continuous improvement of the economic level, so that the construction techniques continue to improve and enhance, which also brought the drainage works continue to pursue large-scale systems and high parameters, this also makes housing construction with more stringent requirements for drainage construction technology design, construction basis and maintenance.In addition, building water supply and drainage system, which only a small part of the pipe network is significantly exposed, and most of the pipe network are very subtle.Therefore, once there are problems in water supply and drainage system of Housing construction , which will have a significant impact on people's lives and production methods , and it is very difficult to repair and the maintenance cost is also very high.This subject of our study is to explore on the construction technologies and measures of water supply and drainage in Housing construction.Combin with his own worhing experience to a certain extent ,the author elaborates and analyzes the process of drainage construction technology and handling measures for pipeline laying to a certain extent.

竞争价值链就是企业与同行业企业的竞争合作链条,竞争价值链协同就是分析如何与同行业企业进行竞争合作,从而获取竞争优势.文章以中小企业为研究对象,运用价值链理论与协同理论,阐述了中小企业竞争价值链协同的内涵,探索了中小企业竞争价值链的协同模式,并提出了中小企业价值链协同机制,为中小企业借助价值链协同来降低成本和提升竞争力提供理论指导和实践借鉴.

An example was used to a residential area of Jinan city domestic miscellaneous rainwater reuse project,on this basis of the example,a general district miscellaneous rainwater reuse planning mode is established,including analyzing the determine the range of rainwater harvesting,the planning rainwater resource potential and miscellaneous water consumption,and then selecting the volume of the storage tank,reasonable rain water purification methods and rainwater harvesting facilities layout,and finally domestic miscellaneous of the planning area economic benefit analysis of rainwater utilization project.Some suggestions about urban rainwater utilization and management for China are put forward.

创新型产业集群在区域产业链中的作用越来越重要,知识传导是其中最为活跃的关键环节.本文对创新型产业集群知识传导驱动力机理的结构进行了分析,并探讨了驱动力机理的要素构成和体系构建.研究表明,知识传导主体、知识传导资源、知识传导能力和知识传导目标是创新型产业集群知识传导的关键要素,其驱动力来自内在动力和外在动力两个方面

随着高校的发展壮大,用电需求不断增长;本文结合高校用电环境的特点探讨分析如何做好高校供配电管理工作。