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991.
Shu‐Kai Yeh Chien‐Hsiung Huang Chi‐Chun Su Kuo‐Chung Cheng Tsu‐Huang Chuang Wen‐Jeng Guo Sea‐Fue Wang 《Polymer Engineering and Science》2013,53(10):2061-2072
In this study, polystyrene/nanographite nanocomposite foams were made by different compounding methods, such as direct compounding, pulverized sonication compounding, and in situ polymerization, to understand the effect of the process variables on the morphology of the nanocomposites and their foam. The foam was made by batch foaming using CO2 as the blowing agent. Various foaming pressures and temperatures were studied. The results indicated that the cell size decreased and the cell morphology was improved with the advanced dispersion of the nanoparticles. Among the three methods, the in situ polymerization method provided the best dispersion and the resulting nanocomposite foam had the finest cell size and the highest cell density. In addition, adding nanoparticles as a nucleating agent can make foams of similar cell size and cell density at a much lower foaming pressure. This result can be explained by the classical nucleation theory. This discovery could open up a newroute to produce microcellular foams at a low foaming pressure. POLYM. ENG. SCI., 53:2061–2072, 2013. © 2013 Society of Plastics Engineers 相似文献
992.
Hsing‐I Hsiang Li‐Then Mei Chi‐Shiung Hsi Wei‐Cheng Wu Jer‐Hao Wu Fu‐Su Yen 《International Journal of Applied Ceramic Technology》2013,10(1):160-167
The Bi2O3–B2O3–ZnO–SiO2 (BB35SZ) glass effects on the sintering behavior and magnetic properties of Bi–Zn co‐doped Co2Y ferrites were investigated in developing low‐temperature‐fired ferrites. The results indicate that BB35SZ glass can be used as a sintering aid to reduce the densification temperature of Co2Y ferrites from 1300°C to 900°C. The 2(Ba0.9Bi0.1O)·2(Zn0.4Co0.4Cu0.2O)·6(Fe1.97Zn0.03O3) ferrite with 4 wt% BB35SZ glass can be densified below 900°C, exhibiting an initial permeability of 3.4 and quality factor of 55. This process provides a promising candidate for multilayer chip magnetic devices for microwave applications. 相似文献
993.
橡胶减摆器的环境适应性研究 总被引:1,自引:0,他引:1
采用电液伺服试验机进行了橡胶减摆器高低温动态特性测试,研究了橡胶减摆器在不同温度环境下动态特性的变化规律,为其在高寒和热带地区的应用提供依据;同时对其湿热、霉菌和盐雾环境适应性进行了测试,为其在潮湿和海洋环境中的应用提供了依据。研究结果表明,当温度在-55~20℃之间时,橡胶减摆器的低温动态刚度与室温下的比值在1~1.7之间;当温度在20~70℃之间时,橡胶减摆器的高温动态刚度与室温下的比值在0.86~1之间;橡胶减摆器具有较好的高低温动态性能;湿热、霉菌和盐雾试验结果表明,橡胶减摆器的环境适应性优良。 相似文献
994.
995.
采用新型分子印迹菌丝体(Penicillium chrysogenum)吸附树脂处理印刷电路板废水,当铜的初始质量浓度为120 mg/L,pH=5时,静态吸附容量为53 mg/g左右,比商业树脂732提高15%左右;解析率在1 min即达到85%以上,而商业树脂732仅为11%.在中试实验中,连续运行80 h后,出口废水中铜质量浓度仍低于1.0 mg/L左右.与传统处理方法相比较,该法简化了废水处理工艺,节省大量的化学药品,大大降低了废水处理成本. 相似文献
996.
Zhouchao Weng Ekkachai Kanchanatip Dwi Hantoko Mi Yan Hongcai Su Sicheng Zhang Guobin Wang 《中国化学工程学报》2020,28(1):293-298
The co-gasification of sewage sludge and palm oil empty fruit bunch (EFB) in supercritical water (SCW) was conducted at 400℃ with a pressure of over 25 MPa. This study aimed to investigate the influence of EFB addition on the syngas production and its composition. The heavy metal distribution and the leaching potential of the solid residue were also assessed. The results showed that syngas yield significantly increased with the addition of EFB into the feedstock. The cold gas efficiency (CGE) and carbon efficiency (CE) of co-gasification were higher than those of individual gasification. The actual syngas production from co-gasification of sludge and EFB was 45% higher than the theoretical total volume. The results indicated that the addition of EFB to sludge had the synergetic promotion effect on syngas production from sludge and EFB in supercritical water. This enhancement might be due to the dissolution of alkali metals from EFB and the adjustment of organic ratio. In addition, higher percentage of heavy metals were deposited and stabilized in the solid residue after SCWG. The leaching concentration of heavy metals from the solid residues was decreased to a level below the standard limit which enables it to be safely disposed of in landfill. In conclusion, the EFB addition has been proved to promote syngas production, as well as, stabilize the heavy metal in solid residues during co-SCWG. 相似文献
997.
998.
Peng Zhang Sihang Tian Yao Yang Zhengliang Huang Jingyuan Sun Zuwei Liao Binbo Jiang Jingdai Wang Yongrong Yang Lei Xie Hongye Su 《American Institute of Chemical Engineers》2019,65(5):e16552
This work investigated flow regimes identification in horizontal pneumatic conveying from the scope of particle motions based on acoustic emission detection. Results showed that the variation of acoustic energy and acoustic energy fraction could be used to identify the transition between suspension flow and stratified flow. Near the transition point, the acoustic energy was maximum, and the energy fraction of particle-wall collision mutated at high mass fluxes. Furthermore, the fluctuation distribution index (FI) was constructed learning from the concept of polymer molecular weight distribution index, and the “circumferential fluctuation difference (D)” was defined. Based on this, new identification criteria and flow regime diagram were established. In suspension flow, D >0. In stratified flow, D <0. While in slug flow, D ≈ 0. According to these criteria, flow regimes can be identified independently of changing trends of measurement parameters. The universality of above criteria was further verified under different operating conditions. 相似文献
999.
热塑性EVA半导电屏蔽料的研制 总被引:2,自引:0,他引:2
研究了基体树脂、导电材料、润滑剂、抗氧剂对热塑性乙烯-乙酸乙烯共聚物(EVA)半导电屏蔽料性能的影响,确立了EVA半导电屏蔽料配方:EVA100份,导电炭黑55份,润滑剂8.5份,抗氧剂0.80份。对产物性能的表征表明,该半导电屏蔽料20℃时的体积电阻率为48.3Ω·cm,拉伸强度为14.2MPa。 相似文献
1000.
Zhen-Yu Chen Ya-Lun Su Yu-Rong Bi Suk Ying Tsang Yu Huang 《Journal of the American Oil Chemists' Society》2000,77(1):73-78
There is an increasing interest in natural antioxidants present in traditional Chinese herbal medicines. The present study
examined the antioxidant activity of heane, acetone, and methanol extracts, as well as baicalein purified from the dry roots
of Scutellaria baicalensis Georgi (common name: Huangqin), in heated canola oil. Oxygen consumption and decreases in linoleic acid linolenic acid content
were monitored in canola oil held at 90–93°C. Among the three extracts, the acetone extract was most effective against oxidation
of canola oil, followed by the methanol extract of the dry roots. The antioxidant activity of these three extracts correlated
well with their content of baicalein, which provided strong protection to canola oil from oxidation. The antioxidant activity
of Huangqin acetone extract was dose-dependent. The acetone extract at 100 ppm or above was even more effective than butylated
hydroxytoluene at 200 ppm in protecting canola oil from oxidation. The present results suggest that the acetone extract of
these roots should be further explored as a potential source of natural antioxidants for use in the processed foods. 相似文献