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991.
993.
为提高聚氨酯泡沫(PUF)的疏水性能,首先采用十六烷基三甲氧基硅烷(HDTMS)对花生壳粉末(PSP)进行改性,得到疏水改性花生壳粉末(H-PSP)。水接触角测试结果表明,改性后H-PSP的水接触角由PSP的0°提高至145.2°。然后采用预聚体法制备了PUF负载H-PSP复合材料(H-PSP-PUF-n,n为H-PSP占聚氨酯预聚体PPU的质量分数)。对H-PSP-PUF-n的结构和性能进行了表征与测试。结果表明,H-PSP的负载提高了泡沫材料的表面粗糙度和力学性能,H-PSP的最佳负载量为PPU质量的10%(H-PSP-PUF-10)。与PUF相比,H-PSP-PUF-10的静态水接触角达到142.4°,较PUF提高了50.4°。对二氯甲烷、石油醚、煤油、二甲苯、环己烷五种油品进行油水分离实验,结果表明,H-PSP-PUF-10对不同油品的吸油倍率在7~9 g/g,而且具有良好的油水选择性。经15次吸附-脱附循环后,H-PSP-PUF-10对各油品的吸油倍率在6.5~8.0 g/g,具有良好的循环利用性。 相似文献
994.
Lanting Ke Xiaobin Liu Bingqing Du Yuanpeng Wang Yanmei Zheng Qingbiao Li 《中国化学工程学报》2022,44(4):182-191
Massive amounts of biogas slurry are produced due to the development of biogas plants. The pollution features and the risk of biogas slurry were fully evaluated in this work. Thirty-one biogas slurry samples were collected from sixteen different cities and five different raw materials biogas plants (e.g. cattle manure, swine manure, straw-manure mixture, kitchen waste and chicken manure). The chemical oxygen demand (COD), ammonia nitrogen (NH4+ - N), anions (e.g. Cl-,SO42-, NO3- and PO4-3), antibiotics (e.g. sulphonamides, quinolones, β2-receptor agonists, macrolides, tetracyclines and crystal violet) and heavy metals (e.g. Cu, Cd, As, Cr, Hg, Zn and Pb) contents from these biogas slurry samples were systematically investigated. On this basis, risk assessment of biogas slurry was also performed. The concentrations of COD, NH4+ and PO4-3 in biogas slurry samples with chicken manure as raw material were significantly higher than those of other raw materials. Therefore, the biogas slurry from chicken manure raw material demonstrated the most serious eutrophication threat. The antibiotic contents in biogas slurry samples from swine manure were the highest among five raw materials, mostly sulphonamides, quinolones and tetracyclines. Biogas slurry revealed particularly serious arsenic contamination and moderate potential ecological risk. The quadratic polynomial stepwise regression model can quantitatively describe the correlation among NH4+ - N, PO4-3 and heavy metals concentration of biogas slurry. This work demonstrated a universal potential threat from biogas slurry that can provide supporting data and theoretical basis for harmless treatment and reuse of biogas slurry. 相似文献
995.
Pascal Habimana Yanjun Jiang Jing Gao Jean Bernard Ndayambaje Osama M. Darwesh Jean Pierre Mwizerwa Xiaobing Zheng Li Ma 《中国化学工程学报》2022,48(8):66-75
The continuous use of chemical dyes in various industries, and their discharge into industrial effluents, results in severe problems to human life and water pollution. Laccases have the ability to decolorize dyes and toxic chemicals in industrial effluents as green biocatalysts. Their possible industrial applications have been limited by poor reusability, low stability, and loss of free laccase action. In this research, laccase was immobilized on zeolitic imidazolate framework coated multi-walled carbon nanotubes (Laccase@ZIF-8@MWCNTs) via metal affinity adsorption to develop an easy separable and stable enzyme. The optimum reaction conditions for immobilized laccase are at a pH of 3.0 and a temperature of 60?℃. The immobilized laccase was enhanced in storage and thermal stability. The results indicated that Laccase@ZIF-8@MWCNTs still maintained 68% of its original activity after 10 times of repeated use. Most importantly, the biocatalytic system was applied for decolorization of different dyes (20?mg·L?1) without a mediator, and up to 97.4% for Eriochrome black T and 95.6% Acid red 88 was achieved in 25 min. Biocatalysts with these properties may be used in a variety of environmental and industrial applications. 相似文献
997.
Zhang Yu Dong Yi Zou Renzhi Zhou Zhiying Hu Wenshuo Ran Mingchu Song Hao Liu Shaojun Zheng Chenghang Gao Xiang 《Catalysis Letters》2022,152(4):1140-1144
Catalysis Letters - Investigation of the low-temperature (LT) selective catalytic reduction (SCR) of NOx has adsorbed extensive efforts, and is now a hot topic in environmental catalysis. In this... 相似文献
998.
Catalysis Letters - The attractive challenge in green chemistry is exploring novel heterogeneous catalyst system for catalyst-controlled product selectivity for oxidation of olefins. Hence, we... 相似文献
999.
Hang Wang Yumin M. Li Liang Zheng Jianjiang Bian 《International Journal of Applied Ceramic Technology》2022,19(4):2064-2072
Structural evolution and microwave dielectric properties of LiNb0.6(Ti1-x[Co1/3Nb2/3]x)0.5O3 (.05≤x≤.2) ceramics have been studied in this paper. Although the doped compositions maintain the M-phase solid solutions, compositional fluctuation due to nonuniform dispersion of minor dopants could be observed as x < .05, and trace amount of Li2TiO3-based solid solution (Li2TiO3ss) secondary phase presents in the x > .05 compositions. The microwave dielectric properties could be remarkably improved by the doping of (Co1/2Nb1/2)4+ in comparison to the undoped counterpart. Optimized microwave dielectric properties with Q × f = ∼6500 GHz, εr = ∼74 and τf = +8.2 ppm/°C could be obtained at x = .10 after sintering at 1050°C/2 h. The sintering temperature could be further reduced to 900°C/2 h by adding .2 wt% B2O3 without affecting significantly its microwave dielectric properties: εr = 73, Q × f = 6000 GHz, τf = +8.5 ppm/°C. The LiNb0.6(Ti1-x[Co1/3Nb2/3]x)0.5O3 ceramics obtained in this case exhibit large dielectric permittivity coupled with much improved Q × f values, near zero τf, and low sintering temperature simultaneously, which makes it a promising high-k microwave dielectric material for low temperature cofired ceramic applications. 相似文献
1000.
文章考虑地基土厚度的影响,对水平动荷载作用下下卧基岩黏弹性地基上刚性条形基础的动力响应问题进行了理论研究。通过傅里叶积分变换求解土的动力控制方程,并结合基底和地基的混合边界条件及土层刚性基岩边界条件,得到了一组对偶积分方程,使用雅可比正交多项式将对偶积分方程转化为线性方程组并进行数值求解。将文章所得解退化至黏弹性半空间情况,与已有文献进行对比,验证了本文解的合理性。参数研究表明:地基土层厚度对条形基础动力柔度系数和地基表面位移的影响显著;由于驻波在地基土层中的共振,使得基础和土体动力响应的变化规律相较于半空间情况更为复杂。 相似文献