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以复合的醋酸镁和醋酸钙(CMA)为主要原料自制除冰融雪剂(PSMA),同时添加缓蚀剂和对植物生长有益的植物钙剂,并使融雪剂显色,通过正交试验法确定最佳配比为a(乙酸钙镁比)∶b(苯甲酸钠)∶c(苯酚)=16∶4∶4∶3。对融雪剂进行性能测定,融雪除冰能力达到了105.44%,最佳融冰时间为80min,最佳融雪比为3∶25,并测定出融雪剂对植物生长无影响,对道路有防锈能力。 相似文献
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以矿粉和工业废醋酸为原料,合成了5种不同钙镁比的矿粉醋酸钙镁(CMA)。研究了矿粉CMA中钙镁比与融冰性能的关系,考察了矿粉CMA及其与五种常规融冰盐添加剂复配后的三元CMA产物的融冰能力及耐腐蚀性。结果表明,五种矿粉CMA具有良好的耐钢铁腐蚀性;醋酸钙、醋酸镁各自的溶解度和溶解放热共同影响CMA的融冰性能,钙镁比在5~0.45间的矿粉CMA产物20%水溶液的冰点均低于-8.5℃;三元CMA复合物的冰点低于二元CMA产物;KAc对CMA产物的冰点降低和融冰速率贡献最大;尿素、NaNO_2、Ca(NO_3)_2能有效提高三元复合融冰剂的耐腐蚀性能。 相似文献
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木醋液制环保型融雪剂技术与应用研究 总被引:1,自引:0,他引:1
木醋液的应用研究主要围绕农业、林业、养殖业、新型环保型融雪剂等方面。重点论述了木醋液制备醋酸钙镁盐(CMA)环保型融雪剂技术。醋酸钙镁盐类融雪剂是替代高速公路除冰剂(氯化钠)而开发的一种新型环保型产品,对公路基础设施中的混凝土与金属的腐蚀性小,基本上对土壤和水源不造成污染,同时具有水溶性好,熔点低,可生物降解等优点。以木醋液为原料,可制得低成本的醋酸钙镁盐类融雪剂,使木醋液变废为宝,既达到了生物质资源的二次利用、又减少了对环境的污染,具有较好的经济效益和社会效益。 相似文献
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综述了国内外融雪剂的种类、优缺点,环保型融雪剂的技术指标以及研究进展与发展动态,重点阐述了低成本醋酸钙镁盐(CMA)类环保型融雪剂的工艺方法与开发工业废液生产无氯融雪剂技术,使废物得到资源化利用并对应用前景做了展望。 相似文献
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为合理利用乳酪和乳酪素的副产品乳清,研究了一种新的厌氧发酵方法将乳清中的乳糖发酵成醋酸,以此醋酸与CaO/MgO反应制备得到环保型融雪剂醋酸钙镁盐(CMA)。第一步用植物乳杆菌将乳清中的乳糖发酵成乳酸,乳酸的转化率是47.47%;第二步用丙酸杆菌将乳酸发酵成醋酸与丙酸,用气相色谱法将二者分离,得到醋酸的转化率为5.643%;用红外光谱法验证了此醋酸与CaO/MgO反应制备得到的CMA的结构。该法既有效地利用了乳酪和乳酪素的副产品乳清,又降低了环保型融雪剂醋酸钙镁盐的生产成本,具有很好的应用前景。 相似文献
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采用对比试验法,以菊科植物为研究对象,研究了CMA(醋酸钙镁盐)环保型融雪剂及氯化钠融雪剂不同浓度下对植物生长生理特性的影响。采用蒽酮比色法研究了融雪剂对植物叶片中可溶性糖含量的影响,采用硫代巴比妥酸法研究了融雪剂对植物叶片中丙二醛的含量的影响,采用分光光度法研究了叶绿素含量的变化。结果表明:CMA融雪剂溶液浇灌过植物叶片中的可溶性糖含量和丙二醛含量均低于NaCl溶液浇灌的植物,与空白实验(水浇灌)的含量相差不大。低浓度(质量浓度≤2g/L)CMA融雪剂处理后叶绿素含量有明显增加,高浓度的浇灌后叶绿素含量略微下降,但明显高于NaCl型融雪剂浇灌过的植物,其含量平均上是空白实验叶绿素含量的1.32倍。 相似文献
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《精细化工原料及中间体》2016,(7)
醋酸钙镁盐(CMA)替代氯盐,用于公路、铁路、机场等道路除雪,是一种环保型融雪(冰)剂。本文介绍了融雪(冰)剂的分类、技术指标,重点介绍了醋酸钙镁法(CMA)的研究进展及应用瓶颈,为CMA的实际应用奠定基础。 相似文献
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Cellulose monoacetate/polycaprolactone and cellulose monoacetate/polycaprolactam blended nanofibers for protease immobilization
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Enzymes can be used multiple times when they are immobilized on a support. More enzymes can be immobilized on a surface when nanofibers are used as a supporting surface because the specific surface area increases tremendously. In this regard, polycaprolactam/cellulose monoacetate (PA6/CMA) and polycaprolactone/cellulose monoacetate (PCL/CMA) blended nanofibers (NFs) were prepared via an electrospinning process. Protease enzymes were immobilized on neat PA6, PCL, PA6/CMA, and PCL/CMA nanofibers and glutaraldehyde (GA) activated analogs through the physical adsorption method. The immobilized enzyme activity was measured by using a casein substrate, and the results were compared with free enzyme activity. Among all of the samples, the highest immobilization yield of about 82% was obtained with GA‐activated neat PCL NF samples. The best remaining activity of the immobilized enzymes on pure CMA NFs was found to be 59% after seven reuses. Even after nine reuses, enzyme activities are still observed on the CMA NF samples. It was expected that the addition of CMA in PCL and PA6 NFs would increase the reusability number to reach the reusability of CMA NFs, but it was not significantly enhanced. If CMA chains could be mostly collected on the sheath or close to the sheath of the NFs during the electrospinnig process, this target could be achieved. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45479. 相似文献
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用NaBH4作还原剂,制备了中性氧化铝(n-Al2O3)负载的Pt-M(M=Fe,Co,Ni,Cu,Mn,Sn)双金属催化剂。考察了过渡金属及反应条件对Pt-M/n-Al2O3催化肉桂醛加氢制肉桂醇的影响。结果表明,Fe改性的Pt/n-Al2O3对催化肉桂醛加氢制肉桂醇具有较好的催化性能,当Pt-Fe/n-Al2O3(中性)催化剂中Pt、Fe的含量均为0.3%时,在70℃,2 MPa氢气条件下反应1.5 h,肉桂醛的转化率为100%,肉桂醇选择性高达84.8%。 相似文献
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Cao Shuang Zhang Haixiang Wang Xueman Peng Miquan Huang Renhua Hong Wei Fu Hailu Chen Xiongbo Lin Zejian 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2023,98(2):506-515
In SCR denitrification technology, the conventional coprecipitation method has the disadvantages of high temperature and difficulty in controlling the precipitation rate. Various CexCuTiO2 catalysts were synthesized using ice-melting (CexCuTi-Ice) and conventional coprecipitation (CexCuTi-Con) methods for the selective catalytic reduction (SCR) of NO with NH3. Ce0.4CuTi-Ice catalyst exhibited excellent catalytic activity among the CexCuTiO2 catalysts, and 80% NOx conversion was achieved within a temperature range of 250–375 °C, exceeding that of Ce0.4CuTi-Con catalyst by 20%; in addition, N2 selectivity was nearly 100%. To elucidate the release characteristics of the precursor solution during ice-melting synthesis, the changes of Cu and Ce concentrations in the solution were investigated by ICP-OES. The precursor solution was released at a slow rate via the ice-melting method, resulting in a large surface area, small crystallite sizes, and effective uniform nanoparticles with abundant active species and increased surface acidity. The promoted mechanism could be attributed to the enhanced oxidation of NO to NO2 at low temperatures and the rapid reaction between NO species and coordinated NH3 at high temperatures. © 2022 Society of Chemical Industry (SCI). 相似文献