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Scale up and stability test for oxidative coupling of methane over na_2WO_4-Mn/SiO_2 catalyst in a 200 ml fixed-bed reactor

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Journal of natural Gas Chemistry 2008年第1期17卷 59-63页

作者： Haitao Liu Xiaolai Wang Dexin Yang Runxiong Gao zhonglai Wang Jian Yang State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of ScienceLanzhou 730000 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

The study of scale up for the oxidative coupling of methane （OCM） has been carried out in a 200 ml stainless steel fixed-bed reactor over a 5wt% na2WO4-1.9wt% Mn/SiO2 （W-Mn/SiO2） catalyst. The effects of reaction conditions were investigated in detail. The results showed that, with increasing reaction temperature, the gas-phase reaction was enhanced and a significant amount of methane was converted into COx; with the CH4/O2 molar ratio of 5, the highest C2 （ethylene and ethane） yield of 25% was achieved; the presence of steam （as diluent） had a positive effect on the C2 selectivity and yield. Under lower methane gaseous hourly space velocity （GHSV）, higher selectivity and yield of C2 were obtained as the result of the decrease of released heat energy. In 100 h reaction time, the C2 selectivity of 66%-61% and C2 yield of 24.2%-25.4% were achieved by a single pass without any significant loss in catalytic performance.

关键词： scale up oxidative coupling of methane W-Mn/SiO2 200 ml fixed-bed reactor

Oxidative coupling of methane over BaCl_2-TiO_2-SnO_2 catalyst

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Journal of natural Gas Chemistry 2012年第1期21卷 49-55页

作者： zhonglai Wang Guojun Zou Xu Luo Hua Liu Runxiong Gao Lingjun Chou Xiaolai Wang State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000GansuChina Graduate University of the Chinese Academy of Sciences Beijing 10039China

The performance of BaC12-TiO2-SnO2 composite catalysts in oxidative coupling of methane reaction has been investigated. A series of BaC12-TiO2, BaC1E-SnO2, TiO2-SnO2, and BaC12-TiO2-SnO2 catalysts were prepared, and characterized by BET, XRD, XPS, CO2-TPD and H2-TPR, respectively. The synergistic effect among BaC12, SnO2 and TiO2 compositions enhances the catalytic performance. The best C2 selectivity and ethylene yield are obtained on the catalyst with the equal molar amount of the three compositions （BaC12 ： TiO2 ： SnO2 molar ratio of 1 ： 1 ： 1）. The optimal reaction conditions are as follows： 800 ℃, 44 ***-1 for methane, 22 ***-1 for oxygen and a space velocity of 5000 mL-h-1 .g-1, and the C2H4 yield over the catalyst is 20.1% with the CH4 conversion of 43.8% and C2 selectivity of 53.3%.

关键词： oxidative coupling of methane BaC12-TiO2-SnO2 catalyst synergistic effect na2WO4-Mn/SiO2 catalyst

Mutagenesis reveals that the rice OsMPT3 gene is an important osmotic regulatory factor

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The Crop Journal 2020年第3期8卷 465-479页

作者： Shengcai Huang Shichao Xin Guoqiang Xie Jiao Han zhonglai Liu Bing Wang Shuqing Zhang Qingyu Wu Xianguo Cheng Laboratory of Plant Nutrition and Biology Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Rubber Biology and Genetic Resources of the Ministry of Agriculture Rubber Research InstituteChinese Academy of Tropical Agricultural SciencesHaikou 571011HainanChina Jiujiang Academy of Agricultural Sciences Jiujiang 332101JiangxiChina Guangling No.5 Middle School Datong 037500ShanxiChina

Plant mitochondrial phosphate transporters regulate phosphate transport and ATP synthesis. Determining whether they function in abiotic stress response process would shed light on their response to salt stress. We used the CRISPR/Cas9 gene-editing system to mutagenize two mitochondrial phosphate transporters, OsMPT3;1 and OsMPT3;2, to investigate their regulatory roles under salt stress. Two cas9(CRISPR-associated protein9)-free homozygous mutants, mpt33 and mpt30, were confirmed to be stable. Both OsMPT3;1 and OsMPT3;2 were markedly induced by salt stress, and their mutagenesis strongly inhibited growth and development, especially under salt stress. Mutagenesis sharply reduced the accumulation of ATP, phosphate, calcium, soluble sugar, and proline and increased osmotic potential, malondialdehyde, and na^+ /K^+ ratio under salt stress. Both mutants demonstrate normal growth and development in the presence of ATP, revealing high sensitivity to exogenous ATP under salt stress. The mutants showed lowered rates of na^+ efflux but also of K^+ and Ca^(2+) influx under salt stress. Mutagenesis of OsMPT3;2 altered the enrichment profiles of differentially expressed genes involved mainly in synthesis of secondary metabolites, metabolism of glycolysis, pyruvate, tricarboxylic acid cycle, in response to salt stress. The mutant displayed significant accumulation differences in 14 metabolites involved in 17 metabolic pathways, and strongly up-regulated the accumulation of glutamine, a precursor in proline synthesis, under salt stress. These findings suggest that the OsMPT3 gene modulates phosphate transport and energy supply for ATP synthesis and triggers changes in accumulation of ions and metabolites participating in osmotic regulation in rice under salt stress, thus increasing rice salt tolerance. This study demonstrates the effective application of CRISPR/Cas9 gene-editing to the investigation of plant functional genes.

关键词： MPT ATP CRISPR Mutagenesis reveals that the rice OsMPT3 gene is an important osmotic regulatory factor

L-酪氨酸在732阳离子交换树脂上吸附平衡与动力学研究

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离子交换与吸附 2008年第1期24卷 55-63页

作者：王中来林森炜卢燕梅福州大学生物科学与工程学院福州大学生物科学与工程学院福州350002

研究搅拌槽中732阳离子交换树脂吸附L-酪氨酸的交换平衡和动力学特性,考查了搅拌速度、温度、料液初始pH值、树脂粒径和料液初浓度对离子交换过程的影响。在研究的温度和浓度范围内,该离子交换等温线符合Henry等温式。搅拌速度为350rpm... 详细信息

研究搅拌槽中732阳离子交换树脂吸附L-酪氨酸的交换平衡和动力学特性,考查了搅拌速度、温度、料液初始pH值、树脂粒径和料液初浓度对离子交换过程的影响。在研究的温度和浓度范围内,该离子交换等温线符合Henry等温式。搅拌速度为350rpm时,可以将外传质阻力忽略。料液初始pH值介于2.5~5.5时,对交换量影响不大,而料液中na+的存在会降低树脂的交换量。在忽略外传质阻力的条件下,采用不同粒径计算方法对动力学曲线影响很小。用间歇搅拌槽吸附动力学模型拟合出无外传质阻力条件下、不同初始浓度条件下离子交换的表面扩散系数DS。结果表明,随着初始浓度的增大,DS的数量级始终在10-8左右。

关键词：酪氨酸离子交换表面扩散系数数值模拟

纳米氧化铝提升海洋环境高速铁路桥梁混凝土结构服役寿命研究

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材料导报 2024年第7期38卷 89-96页

作者：杨志强王振黄法礼易忠来蒋金洋中国铁道科学研究院集团有限公司铁道建筑研究所高速铁路轨道系统全国重点实验室东南大学材料科学与工程学院东南大学江苏省土木工程材料重点实验室

氯离子传输并诱导内部钢筋锈蚀是海洋环境高速铁路桥梁混凝土结构耐久性失效的主要原因之一，增大混凝土氯离子传输阻力是提升混凝土结构服役寿命的根本途径。纳米技术与纳米材料的发展为混凝土材料高性能化提供了新的可能。本工作研究... 详细信息

氯离子传输并诱导内部钢筋锈蚀是海洋环境高速铁路桥梁混凝土结构耐久性失效的主要原因之一，增大混凝土氯离子传输阻力是提升混凝土结构服役寿命的根本途径。纳米技术与纳米材料的发展为混凝土材料高性能化提供了新的可能。本工作研究了纳米氧化铝（na）对砂浆氯离子电迁移系数(DRCM)与自然扩散系数的影响，基于氯离子等温吸附曲线，建立了考虑氯离子结合参数的氯盐传输模型，分析了na对氯盐侵蚀环境下混凝土结构服役寿命的影响。结果表明：适宜掺量的na可降低砂浆氯离子传输性能；承台桩基础混凝土钢筋保护层厚度为60 mm时，在C45混凝土中掺入2%（质量分数）na后，仅考虑氯离子侵蚀时混凝土预期服役寿命由68年提升至107年。na为提升海洋环境下高速铁路混凝土结构服役寿命提供了新的技术途径。

关键词：高速铁路混凝土氯离子纳米氧化铝服役寿命

赤泥基胶凝材料钙硅比对na^＋固化性能的影响

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金属矿山 2008年第6期37卷 130-137,144页

作者：孙文标冯向鹏易忠来河南工程学院首钢总公司清华大学

运用NMR、IR等分析手段,采用结构分析的方法研究了赤泥基胶凝材料的水化过程,揭示了胶凝材料钙硅比对水化产物na+固化性能的影响规律。结果表明,随着钙硅比的降低,在Al对Si的取代作用下,[Si(Al)O4]结构单元聚合度增大,桥[SiO4]、[AlO4]... 详细信息

运用NMR、IR等分析手段,采用结构分析的方法研究了赤泥基胶凝材料的水化过程,揭示了胶凝材料钙硅比对水化产物na+固化性能的影响规律。结果表明,随着钙硅比的降低,在Al对Si的取代作用下,[Si(Al)O4]结构单元聚合度增大,桥[SiO4]、[AlO4]四面体增多,Si以Q1、Q2结构形式存在的C-S-H凝胶转变为具有SiQ2、SiQ3和SiQ4结构单元的(na,Al)-C-S-H凝胶,利于na+以化学吸附和化学固溶形式的固化。

关键词：赤泥基胶凝材料 na^+的固化钙硅比