ZnO－Li_2O－V_2O_5系湿敏电阻材料感湿机理研究

借助扫描式电子显微镜发现ＺｎＯ－Ｌｉ２Ｏ－Ｖ２Ｏ５系湿敏材料是由ＬｉＺｎＶＯ４玻璃包裹ＺｎＣｒ２Ｏ４晶粒并相互粘结而成，根据ＬｉＺｎＶＯ４玻璃的形成过程及其微观结构，提出了该系湿敏材料的感湿机理，认为嵌在玻璃相空穴中的Ｌｉ＋和Ｌｉ２Ｏ分别构成了玻璃本体电导和感湿点；由此解释了实测的电阻－湿度特性曲线，并提出可以分别通过调节Ｌｉ＋和Ｌｉ２Ｏ的浓度改变材料的本体电阻和感湿灵敏度．     

表层静电植入与贴伏石墨烯的湿敏聚氨酯纤维制备及其性能

为制备性能优良、环保且适合编织的湿敏纤维,采用表层静电植入法,在静电场中将石墨烯快速植入熔融状态的聚氨酯纤维表层,经快速辊压贴伏制备出类羊毛鳞片状、湿度敏感的聚氨酯湿敏纤维。通过对纤维的制备工艺进行优化,同时对纤维的结构和性能进行分析。结果表明:聚氨酯湿敏纤维的最佳制备工艺为电极板接收距离为15 cm,电压为45 kV,温度为50 ℃,植入时间为15 s;当石墨烯质量分数为4.1%时,湿敏纤维的电导率为7.0 S/m, 断裂强度为94.9 MPa,断裂伸长率91.5%;该湿敏纤维具有良好的湿度敏感稳定性,在高湿环境下具有良好的电阻敏感性,在低湿下具有更短的响应时间(16 s)和恢复时间(26 s);该湿敏纤维在腐蚀性气体环境和柔性智能电子纺织品上具有广泛的应用潜力。     

钛掺杂的α-Fe2O3-K2O系纳米湿敏陶瓷的复阻抗谱

采用硬脂酸凝胶法这种化学新工艺制备了α Fe2 O3 TiO2 K2 O复合氧化物纳米湿敏陶瓷元件 ;研究了该元件在不同湿度下的复阻抗谱 ,并建立相应的模拟等效电路 ;材料晶粒电阻、晶界电阻等特征参数计算结果表明 ,晶粒电阻基本不随湿度变化 ,晶界电阻随湿度升高而降低 .从晶界电阻角度探讨了本系材料的湿敏导电机制 ,低湿阶段导电载流子为电子和自由H ,自由H 以氢桥键过渡态机制迁移 ,中、高湿阶段导电载流子以H3O 为主 .     

ZnCr2O4-V2O5-Li2O-ZnO湿敏材料本体电导成因

研究了ZnCr2O4-V2O5-Li2O-ZnO湿敏材料在干燥状态下的电导类型和在感湿状态下的导电离子类型,对样品在不同湿度下的电子电导和离子电导进行分离测试并与纯水相应量的测试结果作对比,提出该系材料的本体电导只有电子电导,没有离子电导;本体电导所对应的电子电导值取决于晶粒和粒间玻璃相的电导,不因感湿而改变,这为调节相应湿敏元件本体电阻提供了便利.     

添加石墨粉对锐钛矿型TiO_2－V_2O_5系湿敏材料的影响

研究了添加石墨粉、烧结温度及时间对锐铁矿型ＴｉＯ＿２－Ｖ＿２Ｏ＿５系多孔湿敏材料的微结构及湿敏性能等的影响。结果表明：添加石墨粉改善了材料的微结构，提高了湿敏元件的湿度灵敏度和长期稳定性；材料以添加ｗ为５％～１０％的石墨粉，９００℃烧结２ｈ湿敏性能最好。     

溶胶-凝胶法制备的硅掺杂α-Fe2O3-K2O多孔陶瓷的湿敏性能

采用溶胶 凝胶工艺在α Fe2 O3 K2 O复合体系中掺入SiO2 .XRD、BET比表面吸附、Archimede排水法等对α Fe2 O3 K2 O SiO2 陶瓷表征结果表明 ,适量掺杂SiO2 ,材料仍以刚玉结构的α Fe2 O3为主晶相 ,但抑制了主晶相晶粒粗化 ,增大了材料比表面积及孔隙率 .湿敏性能测试发现 ,掺杂摩尔分数 6%的SiO2 ,可获得全湿区范围内阻—湿特性曲线线性关系良好、灵敏度适中、湿滞小、稳定性较高的新型湿敏材料 .其中 ,K 被吸收分散在主晶相晶界硅玻璃相中是改善材料湿滞效应及性能稳定性的主要原因 .     

α-Fe_2O_3-Al_2O_3-Na_2O纳米陶瓷制备及其湿敏特性

采用溶胶－凝胶法制备了α－Ｆｅ２Ｏ３－Ａｌ２Ｏ３－Ｎａ２Ｏ复合超微粉,对微粉及其烧结后的物相及粒度进行了分析。湿敏特性测试结果表明：纳米级α－Ｆｅ２Ｏ３－Ａｌ２Ｏ３－Ｎａ２Ｏ陶瓷元件的感湿灵敏度高于简单氧化物机械混合后制成的α－Ｆｅ２Ｏ３－Ａｌ２Ｏ３－Ｎａ２Ｏ陶瓷元件,并具有较快的响应特性及较好的稳定性。     

硼掺杂对α-Fe2O3-K2O湿敏半导体陶瓷结构与性能的影响

用硬脂酸凝胶法工艺合成不同配比的α Fe2 O3 K2 O B2 O3复合氧化物超微粉 ,经液相烧结法制得多孔陶瓷材料 .采用XRD技术、Archimede排水法及压汞法等研究了材料物相、晶粒度及微孔结构 ;电导测试实验表明 ,B2 O3掺杂相可能以非晶态均匀包覆在主晶相晶粒表面及晶界处 ,K 被吸收包埋在B2 O3非晶相中 ;湿敏特性测试结果表明 ,硼掺杂 5% (摩尔分数 )左右 ,全湿区内材料阻 湿特性曲线线性关系良好 ,且感湿灵敏度较高、湿滞小 ,改变掺杂配比 ,可获得不同湿敏转变点的阻 湿特性曲线 ;初步探讨了材料多孔结构与湿敏性能之间的关系 ,得出通过硼掺杂调控材料微结构 ,可明显提高材料湿敏性能稳定性的结论 .     

北京市亚都环境测控工程公司系列产品介绍

北京市亚都环境测控工程公司是北京亚都企业发展总公司的全资子公司,注册于北京市新技术产业开发试验区,是具有独立法人地位的公司.目前公司拥有50余名科技人员,开发领域涵盖机械、电子、化工、材料、计算机、环境及气象科学诸多学科.主要产品是各种温、湿度传感器、控制器、测量仪表、工业用大型加湿器系列.MS型湿度传感器MS-1 型湿度传感器是由湿敏电阻和热敏电阻组成.本品具有灵敏度高,响应速度快等优点.不仅适用于加湿器的自动控制,而且适用于其它设备的湿度测量与控制.MS-2型湿度传感器采用感湿特性优越的湿敏材料浸在具有独特结构的多孔陶瓷基片内,成为具有良好稳定性和耐环境污染能力高的可     

北京市亚都环境测控工程公司系列产品介绍

北京市亚都环境测控工程公司是北京亚都企业发展总公司的全资子公司,注册于北京市新技术产业开发试验区,是具有独立法人地位的公司.目前公司拥有50余名科技人员,开发领域涵盖机械、电子、化工、材料、计算机、环境及气象科学诸多学科.主要产品是各种温、湿度传感器、控制器、测量仪表、工业用大型加湿器系列.MS型湿度传感器MS-1型湿度传感器是由湿敏电阻和热敏电阻组成.本品具有灵敏度高,响应速度快等优点.不仅适用于加湿器的自动控制,而且适用于其它设备的湿度测量与控制.MS-2型湿度传感器采用感湿特性优越的湿敏材料浸在具有独特结构的多孔陶瓷基片内,成为具有良好稳定性和耐环境污染能力高的可靠湿敏电阻,并配以高精度的补偿温度用热敏电阻.具有测量精度高,响应速度快,耐环境污染能力强,长期稳定性好等特点,可广泛用于电子、纺织、烟草、环保、食品、仓储、建筑、印刷等行业中的湿度测量与控制.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of     

The Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.