Preparation and flocculation properties of cationic starch/chitosan crosslinking-copolymer

A novel flocculant (CATCS) based on corn starch and chitosan was prepared and its flocculation behaviors were studied. The synthesis conditions of CATCS were discussed and the production obtained was characterized using Fourier infrared spectra and scanning electron microscopy. Flocculation properties of the products were evaluated in terms of transmittance, removal of organic contaminant and solid suspending substances. Influences of temperature, pH and flocculant dosage on flocculation efficiency of CATCS were examined. CATCS had better flocculation performance at lower temperature for the wastewater investigated. CATCS showed better flocculation performance than cationic starch and chitosan in 5 g/L kaolin suspension trended to performance well in acidic and alkaline solution. The comparison of the flocculation performance between CATCS, Fe₂ (SO₄)₃ and polyacrylamide showed CATCS had much efficient flocculation performance. In addition, cationic starch was prepared from corn starch using microwave-assisted method.     

透明导电ZnO∶Al(ZAO)纳米薄膜的性能分析

用直流反应磁控溅射法制备ZAO纳米薄膜 ,对这种薄膜进行了XRD分析 ,并对其光、电性能作了详细的研究。结果表明 :ZAO薄膜的结构为标准的ZnO纤锌矿相 ,没有Al2 O3 相出现 ;其最低电阻率为 4 5× 10 -4Ω·cm、可见光透射率在 80 %以上 ,红外波段的反射率达 70 %以上 ,是优质的透明导电膜     

基体温度对磁控溅射沉积ZAO薄膜性能的影响

利用中频交流磁控溅射方法 ,采用氧化锌铝陶瓷靶材 [w(ZnO) =98%、w(Al2 O3 ) =2 % ]制备了ZAO(ZnO∶Al)薄膜 ,观察了基体温度对ZAO薄膜的晶体结构、电学和光学性能的影响 ,采用X射线衍射仪对薄膜的结构进行了分析 ,采用光学分度计和电阻测试仪测量了薄膜的光学、电学特性 ,采用霍尔测试仪测量了薄膜的载流子浓度和霍尔迁移率。结果表明 :沉积薄膜时的基体温度对薄膜的结构、结晶状况、可见光透射率以及导电性有较大的影响。当基体温度为 2 5 0℃ ,Ar分压为 0 8Pa时 ,薄膜的最低电阻率为 4 6× 10 -4Ω·cm ,方块电阻为 35Ω时 ,可见光 (λ =5 5 0nm)透射率高达 92 0 %。     

功率密度对中频磁控溅射制备的氧化锌镓薄膜性能的影响

利用中频磁控溅射方法,溅射Ga2O3含量为6.7wt%的氧化锌镓陶瓷靶材,在低温下(约40℃)制备了ZGO薄膜.考察了溅射功率密度对ZGO薄膜的晶体结构、电学和光学性能的影响.结果表明:溅射功率密度对薄膜的结构、红外反射以及导电性能有较大影响.当溅射功率密度为3.58W/cm2,氩气压力为0.8Pa时,薄膜的电阻率低达1.5×10-3Ω·cm,方块电阻为23Ω时,可见光(λ＝400nm～800nm)平均透过率高于90%.     

不锈钢长丝嵌织密度对织物屏蔽效能的影响

探讨棉不锈钢长丝合股纱嵌织密度及电磁波辐射角度对棉不锈钢长丝嵌织织物屏蔽效果的影响。测试了不同棉不锈钢长丝合股纱纬密及不同电磁波入射角度条件下织物的屏蔽效果。测试结果表明:织物屏蔽效能随着棉不锈钢长丝合股纱嵌织密度的增大而增大,在达到临界值后基本稳定不变;织物电磁透过率随着电磁入射角度的变化呈余弦平方曲线变化。指出:实际生产中,在保证织物屏蔽效果的基础上,应合理选择金属纤维纱线嵌织密度以节省原料;尽量在织物经纬向都加入金属纤维纱线以达到理想的屏蔽效果。     

紫外线数字仪的设计

研究紫外光波对人眼的伤害是近年来国际眼科界关心的重点之一.由于防紫外线眼镜片的紫外透射比对人眼的健康至关重要,消费者、技术监督部门以及眼镜销售商都希望有相应的检测手段及仪器,因此,设计研制紫外线数字仪具有重要意义和市场前景.研究了紫外光波透射比的检测方法,采用合适的光源、单色器、光电探测器及单片机等构成一种能测量镀膜片及普通光学镜片紫外线透射比的紫外线数字仪.主要介绍仪器的测量原理及单片机软硬件设计.     

Study on the ion-exchange copper-loaded antibacterial glasses

In this paper, copper-loaded antibacterial glasses were prepared by an ion-exchange method with CuSO₄ or CuCl as copper sources. The effects of different molten salts and ion exchange duration on the antibacterial properties of copper-loaded glasses were investigated. The experimental results show that the glasses exchanged with CuSO₄/Na₂SO₄ mixed molten salts have a higher surface copper loading than that with CuCl/KCl mixed molten salts. The sample color results from the reduced Cu⁰. The equilibrium between Cu⁺ and Cu⁰ is related to the Sn²⁺ ions existed in the lower surface of float glass. Finally, the antibacterial function of glass samples was found to be related to the charge transfer between Cu⁺+e^??Cu⁰, and has a proportional correlation with the content of Cu⁺ ions on the glass surface.     

保险粉法合成紫外线吸收剂UV-326

以保险粉作还原剂,通过重氮化、偶合、还原反应合成了紫外线吸收剂UV-326。研究了还原反应的投料比、温度以及氢氧化钠溶液浓度等因素对反应收率和产品质量的影响。结果表明：较理想的反应条件是偶合物、保险粉与氢氧化钠的物质的量比为1：3．5：10．5,氢氧化钠溶液溶度为18％,在8l℃下反应0．5h,总产率达86％以上,产品纯度为99．9％。以该工艺合成的紫外线吸收剂具有优良的紫外吸收能力,且在500nm可见光处的透光率为99．7％。     

Aerosol-deposited Al2O3/PTFE hydrophobic coatings with adjustable transparency

With the wide range of requirements for architectural glass, such as transparency, opacity, and hydrophobicity, there is a need to address the issues in the complexity of convention methods. Thus, considering functionality and applicability in various architectural windows, hydrophobic alumina/polytetrafluoroethylene (Al₂O₃/PTFE) composite layers with transparency or opacity were transferred to commercial architectural glass using a facile aerosol deposition (AD) process. We successfully fabricated hydrophobic coating layers with high transmittance (only a 0.03% difference from sheet glass) by optimizing the PTFE content in Al₂O₃ using solution-based synthesized powders to enable a uniform surface topology. The opaque hydrophobic Al₂O₃/PTFE coating layers exhibit a transmittance of approximately 0% with excellent hydrophobicity of 130°. Remarkably, this opaque film was successfully employed onto a large deposition area, curved substrate, and micro-patterned regions. It is believed that our AD-prepared composite layers have great potential for architectural glass in terms of economic feasibility and versatility.     

Fabrication of highly transparent and superhydrophobic silica-based surface by TEOS/PPG hybrid with adjustment of the pH value

Preparation of superhydrophobic silica-based thin film with high transmittance (T%) in the visible light region by adjusting different pH value of mixing solution has been developed. The hybrid films were coated by the mixing solution which included precursor solution (sol–gel process) and polypropylene glycol (PPG) polymer solution. Rough surfaces were obtained by removing the organic polymer at high temperature and then the hydrophobic groups bonded onto the films were obtained by the reaction with hexamethyldisilazane (HMDS). Characteristic properties of the as-prepared surface of the films were analyzed by contact angle measurement, scanning electron microscopy (SEM), atom force microscopy (AFM), UV–VIS scanning spectrophotometer and Fourier transform infrared (FT-IR) spectrophotometer. The experimental parameters were mainly varied by the pH value (0, 1, 2.3, 6 and 8) of the mixing solution. The result showed that the contact angle of the film was greater than 150° and the transmittance of the film was greater than 90% simultaneously when the pH value of mixing solution was adjusted to 1. In addition, the highly transparent superhydrophobic surfaces was obtained by adding 20 μL acid solution into the mixing solution, which the contact angle of the film was 156.3° as well as the transmittance of the film at the 600 nm visible light was 97.9%.