片式电容器用石墨浆料的分散稳定性

以石墨为导电填料,羧甲基纤维素钠(CMC)为分散剂,制备了片式电容器用石墨浆料。用吸光光度法对其进行了稳定性测试,讨论了CMC、聚乙烯醇(PVA)和苯丙乳液用量对浆料稳定性的影响和球磨时间对粒径的影响。结果表明:当CMC干料与石墨的质量比为0.035时,体系稳定性最好。苯丙乳液对体系稳定性影响不大,可作为成膜粘合剂使用。球磨90min为适宜时间,粒径集中在较小的范围,平均粒径6.374μm。     

Sol–gel fabrication and enhanced optical properties,photocatalysis, and surface wettability of nanostructured titanium dioxide films

TiO₂ photocatalytic film, annealed at temperatures of 500 °C and 700 °C, was prepared on SiO₂ pre-coated glass via sol–gel technique for photocatalytic purposes and effects of catalyst-type on its properties were investigated by an X-ray diffractometer (XRD), Scanning Electron Microscope, UV–vis spectrophotometer, and contact angle measurements. The XRD results showed that present phases depend upon catalyst used in the solution and phase transformation behaves in a temperature-dependent manner. For the layers derived from sols containing acidic catalysts, the anatase structure dominated and exhibited much better photocatalytic activity. The results indicated that the sample derived from sol comprises H₂SO₄ as catalyst, and exhibits anatase grains with the lowest size. This could be the reason for its better photocatalytic activity. Finally, samples derived from sol containing acidic catalysts showed superhydrophilicity and superior cleaning ability.     

Water Vapor Permeability of Whey Protein Emulsion Films as Affected by pH

The water vapor permeability (WVP) of whey protein isolate-beeswax emulsion films was investigated as related to pH. Lower WVP was observed for films cast from solutions at pH 7.0. When pH of the film-forming solution was lowered, resulting film WVP increased. At the isoelectric point, WVP was the highest. As pH of the emulsion approached pI, a sharp change in viscosity occurred due to an increase in protein aggregation. This increase in viscosity probably lowered lipid mobility and reduced interconnectivity among lipid droplets, resulting in the higher WVP. For minimum WVP, such films should be applied at pH different from pI.     

超低醛网印粘合剂的合成与应用

采用核壳聚合机理,用Ｎ,Ｎ‘－亚甲基双丙烯酰胺作互穿聚合物网络的交联剂,以达到盐－还原剂体系将高活性的环氧基单体接入高分子上,从而得到超低醛,核软壳硬,且各项性能较优的自交联网印粘合剂。     

Evaluation of antioxidative activity of vegetable extracts in linoleic acid emulsion and phospholipid bilayers

The antioxidative effects of vegetable extracts were evaluated using linoleic acid emulsion and liposomal phospholipid suspension systems. First, the antioxidative activities of water, ethanol and 2% metaphosphoric acid extracts of the vegetables were investigated by measuring the rate of oxygen consumption in the peroxidation of linoleic acid initiated by a radical generator, 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH), with a Clark electrode in the absence of metal chelators. Ethanol extracts of moroheiya and perilla exhibited the highest antioxidative activities. Without metal chelators, 12 ethanol extracts and one water extract acted as prooxidants, and this phenomenon could be attributed to the prooxidant action of ascorbic acid in the presence of free transition metal ions. Next, peroxyl radical-scavenging activities of vegetable extracts were examined by adding a metal chelator, diethylenetriaminepentaacetic acid (DTPA), to the linoleic acid emulsion system. The results were compared with their antioxidative activities in phospholipid bilayers by measuring the inhibition of lipid peroxidation in large unilamellar vesicles composed of egg yolk phosphatidylcholine (PC). A good correlation was observed between the antioxidative activities obtained from these two systems. The antioxidative activities in the liposomal phospholipid suspension system correlated with total contents of ascorbic acid and polyphenols in vegetable extracts. © 1999 Society of Chemical Industry     

航空煤油的羟丙基纤维素凝胶力学性能研究

采用软固体测定仪，研究了胶凝剂、表面活性剂、稳定剂用量对航空煤油凝胶力学性能的影响。结果表明在实验条件下，随胶凝剂用量和表面活性剂OP-10用量的增加，凝胶的屈服应力增加。引入稳定剂C可使凝胶形成时间显著缩短，抗剪切能力显著增强。     

乳肢基质抗冲击波性能研究

研究乳胶基质的抗冲击波性能对于认识乳化炸药的压力减敏机理有意义。乳胶基质受到冲击波作用后，添加一定量的空心玻璃微球，将其爆炸性能与预先加入相同含量空心玻璃微球做成的乳化炸药，受到冲击波作用后的爆炸性能作了比较。结果表明乳胶基质的抗冲击波性能优于乳化炸药，并对此作了分析，认为敏化剂的加入使炸药内部具有许多微小的界面，冲击波对乳化炸药作用时很容易使界面附近的乳胶体破乳，从而使炸药爆炸性能下降。     

功率型白光LED平面涂层技术研究

基于水溶性感光胶的白光LED表面涂层技术,阐述了含有荧光粉感光胶悬浮液的配比和封装结构对白光LED出光效率的影响,提出了相应的改进措施,通过实验证实提高了白光LED器件的整体性能.同时,对利用该法得到的功率型白光LED进行了光衰减测试,LED在700mA电流下点亮168 h后,光输出为初始光输出的95.95%,满足实用要求.     

Drawing a Pencil‐Trace Cathode for a High‐Performance Polymer‐Based Li–CO2 Battery with Redox Mediator

Lithium–carbon dioxide (Li–CO₂) batteries have received wide attention due to their high theoretical energy density and CO₂ capture capability. However, this system still faces poor cycling performance and huge overpotential, which stems from the leakage/volatilization of liquid electrolyte and instability of the cathode. A gel polymer electrolyte (GPE)‐based Li–CO₂ battery by using a novel pencil‐trace cathode and 0.0025 mol L^?1 (M) binuclear cobalt phthalocyanine (Bi‐CoPc)‐containing GPE (Bi‐CoPc‐GPE) is developed here. The cathode, which is prepared by pencil drawing on carbon paper, is stable because of its typical limited‐layered graphitic structure without any binder. In addition, Bi‐CoPc‐GPE, which consists of polymer matrix filled with liquid electrolyte, exhibits excellent ion conductivity (0.86 mS cm^?1), effective protection for Li anode, and superior leakproof property. Moreover, Bi‐CoPc acts as a redox mediator to promote the decomposition of discharge products at low charge potential. Interestingly, different from polymer‐shaped discharge products formed in liquid electrolyte–based Li–CO₂ batteries, the morphology of products in Li–CO₂ batteries using Bi‐CoPc‐GPE is film‐like. Hence, this polymer‐based Li–CO₂ battery shows super‐high discharge capacity, low overpotential, and even steadily runs for 120 cycles. This study may pave a new way to develop high‐performance Li–CO₂ batteries.     

笼统注入时弱凝胶穿透深度分析

弱凝胶驱油技术能够大幅提高采收率,已成为油田三次采油的一项重要技术。根据达西定律和质量守恒定律,建立了线性和径向流条件下弱凝胶在不同渗透率岩心里的穿透深度的数学模型,该模型可用于分析笼统注入条件下影响弱凝胶选择性进入地层能力的因素。结果表明,弱凝胶在低渗透层的穿透深度随渗透率级差增大而减少,随阻力系数增大而增加;在相同条件下,线性流时在低渗透层的穿透深度低于径向流。这些结论对弱凝胶的现场应用具有重要的指导意义。