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Search Results: 1 - 10 of 136632 matches for " QIN Zhang-feng "
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Synthesis and characterization of CoAPO-5 and MnAPO-5 for selective oxidation of cyclohexane
CoAPO-5和MnAPO-5分子筛的合成、表征及在环己烷选择氧化反应中的应用

ZHANG Rui-zhen,DONG Mei,QIN Zhang-feng,WANG Jian-guo,
张瑞珍
,董梅,秦张峰,王建国

燃料化学学报 , 2007,
Abstract: 合成一系列具有不同质量分数Co、Mn的磷铝分子筛CoAPO-5和MnAPO-5;通过X-衍射、扫描电镜、氮气物理吸附、热重分析以及紫外可见漫反射光谱等技术对分子筛的结构、形貌以及Co、Mn原子在分子筛骨架中的存在状态进行了表征;考察了氧气作氧化剂时分子筛在环己烷低温液相氧化反应中的催化性能。结果表明,所合成的CoAPO-5和MnAPO-5具有典型的AlPO4-5分子筛结构,金属Me/P比小于0.1时,分子筛结晶度较高。金属的种类、价态、质量分数及存在形式决定了模板剂与分子筛骨架作用的强度及方式,而有机模板剂的脱附、燃烧温度与这种作用密切相关;部分模板剂需在高温下脱除,说明分子筛骨架与模板剂之间存在着强相互作用。在CoAPO-5和MnAPO-5分子筛的骨架结构中,存在四配位的Co(Ⅱ)和Mn(Ⅱ),经过焙烧可以部分氧化为Co(Ⅲ)和Mn(Ⅲ),说明在焙烧样中存在着氧化还原活性中心。对于环己烷选择氧化反应,CoAPO.5和MnAPO-5分子筛都具有适中的催化活性,氧化反应产物分布均随反应时间而变化。虽然MnAPO-5的催化活性比CoAPO.5高,但其深度氧化能力也较强;采用MnAPO-5为催化剂,环己烷氧化反应的环己酮选择性及深度氧化产物的量都较高。同时,骨架Co质量分数对环己烷氧化反应活性具有显著影响,Co/P比为0.05的CoAPO-5分子筛催化活性最高,130℃反应24h,主要目的产物环己醇和环己酮的选择性可达88.5%。
Deactivation of catalyst in benzene alkylation with propene under different reaction conditions
不同条件下苯与丙烯烷基化反应的催化剂失活研究

TIAN Zhen,QIN Zhang-feng,WANG Guo-fu,DONG Mei,WANG Jian-guo,
田震
,秦张峰,王国富,董梅,王建国

燃料化学学报 , 2006,
Abstract: 对不同条件下苯与丙烯烷基化反应HB催化剂的寿命、失活催化剂的积炭量和积炭性质进行了研究。在5.7MPa下,随反应温度变化,反应介质在反应过程中所经历的相态变化不同,导致催化剂的寿命、失活催化剂的积炭量和积炭的性质也存在着较大差异。300℃时,反应介质处于接近于体系临界点的超临界相或高压液相状态,催化剂寿命最长,积炭量大。失活催化剂积炭的元素分析及TPO-MS表征结果发现,积炭的碳氢比与反应温度有关,温度越高,碳氢比越高;而积炭的脱炭温度与反应时间(催化剂寿命)相关,催化剂寿命越长,相应的脱炭温度也越高。
ACYLATION OF TOLUENE WITH ACETIC ANHYDRIDE OVER H β ZEOLITE
Hβ分子筛催化的甲苯与乙酸酐(AA)酰化反应研究

HU Tuo-ping,QIN Zhang-feng,WANG Jian-guoChinese Academy of Sciences,Taiyuan,China,
胡拖平
,秦张峰,王建国

燃料化学学报 , 2003,
Abstract: 以Hβ分子筛为催化剂,对甲苯与乙酸酐(AA)的酰化反应进行了研究。通过研究反应温度、压力、甲苯与乙酸酐(AA)摩尔比、催化剂用量、以及溶剂的种类和用量等因素对反应转化率和选择性的影响,确定了较优的反应条件。结果表明,Hβ分子筛对甲苯与乙酸酐(AA)酰化反应具有较好的催化活性和选择性,适宜的反应条件为:温度130℃、甲苯/乙酸酐(AA)摩尔比20、催化剂/乙酸酐(从)重量比0.8,极性溶剂如硝基苯等对酰化反应有一定的促进作用,但选择性有所下将,而非极性溶剂如二氧化碳可部分抑制催化剂的失活。
Synthesis of diphenyl carbonate from phenol and CO2 with mesoporous SiMCM-41 supported catalysts
介孔催化剂上苯酚和二氧化碳直接合成碳酸二苯酯

LI Zhen-huan,QIN Zhang-feng,WANG Jian-guo,
李振环
,秦张峰,王建国

燃料化学学报 , 2007,
Abstract: 采用等体积浸渍法制备了介孔分子筛SiMCM-41负载的ZnCl2、ZnO、FeCl3和Fe2O3催化剂,并用于苯酚与二氧化碳在CCl4溶液中合成碳酸二苯酯.采用29SiNMR、ICP、XRD和UV-Raman等技术对催化剂的结构性质、活性组分和载体间的相互作用以及反应前后催化剂结构变化等进行了研究.结果表明,载体SiMCM-41在反应过程中表现出较高的稳定性,ZnCl2、ZnO、FeCl3及Fe2O3负载到介孔SiMCM-41上,金属离子和载体表面硅羟基结合生成固载型活性中心,防止了金属离子在反应过程中从催化剂表面的流失.以二氧化碳、苯酚和碳酸钾为原料,在四氯化碳溶液中反应合成碳酸二苯酯(DPC)时,锌负载催化剂具有较高的催化活性和DPC选择性.
Alkylation of benzene with propene over Hβ zeolite modified with citric acid
柠檬酸改性Hβ分子筛上的苯与丙烯烷基化反应

TIAN Zhen,QIN Zhang-feng,WANG Guo-fu,DONG Mei,WANG Jian-guo,
田 震
,秦张峰,王国富,董 梅,王建国

燃料化学学报 , 2006,
Abstract: 研究了柠檬酸改性对Hβ分子筛上苯与丙烯烷基化反应性能的影响。通过比较分析改性前后催化剂寿命、二异丙苯选择性及其异构体组成分布等的变化。结果表明,二异丙苯的选择性及各异构体的分布与催化剂的酸密度和酸强度有关;较高酸密度和酸强度有利于烷基转移反应的进行,但却加快了催化剂的失活。柠檬酸改性处理可调节Hβ分子筛的酸密度和酸强度,改善苯烷基化的催化反应性能。经0.50mol/L的柠檬酸处理后,Hβ催化剂的寿命比原来延长30%,正丙苯的质量分数减少90%。
Acylation of anisole with acetic anhydride over Hβ/MCM-41 composite molecular sieves
Hβ/MCM-41复合分子筛催化剂上苯甲醚与乙酸酐酰化反应研究

JI Xiang-fei,QIN Zhang-feng,DONG Mei,WANG Guo-fu,WANG Jian-guo,
吉向飞
,秦张峰,董梅,王国富,王建国

燃料化学学报 , 2008,
Abstract: 以β沸石为硅源,制备了不同硅铝比的Hβ/MCM-41复合分子筛,考察了该复合分子筛对苯甲醚与乙酸酐酰化反应的催化效果,并与介孔MCM-41、微孔Hβ分子筛的催化效果进行了比较,研究了分子筛硅铝比、酸性及孔道结构对酰化反应催化性能的影响.结果表明,对于苯甲醚和乙酸酐酰化反应,Hβ/MCM-41复合分子筛具有较好的催化稳定性,反应过程中的积炭量较少,积炭的碳氢比较低.该复合分子筛不仪具有微孔沸石的强酸性,而且具有较大孔径的介孔,产物分子能及时从孔道中扩散出来,催化活性位不易中毒失活.
Selective oxidation of methanol to dimethoxymethane over V2O5/TiO2-ZrO2 catalyst
V2O5/TiO2-ZrO2催化剂上甲醇选择氧化制甲缩醛

WU Jian-bing,WANG Hui,QIN Zhang-feng,WU Zhi-wei,HUANG Li-chun,ZHAO Qi,WANG Jian-guo,
武建兵
,王辉,秦张峰,吴志伟,黄礼春,赵启,王建国

燃料化学学报 , 2011,
Abstract: The composite TiO2-ZrO2 support was prepared through co-precipitation of Ti(SO4)2 and Zr(SO4)2 solution and V2O5/TiO2-ZrO2 catalysts with different vanadium loadings were obtained by incipient impregnation with ammonium metavanadate solution.The catalytic performance of V2O5/TiO2-ZrO2 in the selective oxidation of methanol to dimethoxymethane(DMM) was investigated under mild reaction conditions.The V2O5/TiO2-ZrO2 catalyst performs better in the selective oxidation of methanol than V2O5 supported on the sing...
Tumorigenesis role and clinical significance of DJ-1, a negative regulator of PTEN, in supraglottic squamous cell carcinoma
Zhu Xiao-Lin,Wang Zhang-Feng,Lei Wen-Bin,Zhuang Hui-Wen
Journal of Experimental & Clinical Cancer Research , 2012, DOI: 10.1186/1756-9966-31-94
Abstract: Background DJ-1 can induce the tumor cell proliferation and invasion via down-regulating PTEN in many malignant tumors, and correlated to prognostic significance. However, the tumorigenesis role and clinical significance of DJ-1 in supraglottic squamous cell carcinoma (SSCC) is unclear. We aimed to evaluate the DJ-1 the relationship between DJ-1 and clinicopathological data including patient survival. Methods The expression of DJ-1 and PTEN in SSCCs (52) and adjacent non-cancerous tissues (42) was assessed by immunohistochemistry (IHC), and the relationship between DJ-1 and clinicopathological data was analyzed. Results DJ-1 was detected mainly in SSCCs (88.5%) and less frequently in adjacent non-cancerous tissues (21.0%). PTEN expression was detected in 46.2% of SSCCs and in 90.5% of adjacent non-cancerous tissues. DJ-1 expression was linked to nodal status (P = 0.009), a highly significant association of DJ-1 expression with shortened patient overall survival (5-year survival rate 88.0% versus 53.9%; P = 0.007; log rank test) was demonstrated. Conclusions Our data suggested that DJ-1 over-expression was linked to nodal status, and might be an independent prognostic marker for patients with SSCC.
In Vitro and In Vivo Effect of 5-FC Combined Gene Therapy with TNF-α and CD Suicide Gene on Human Laryngeal Carcinoma Cell Line Hep-2
Li-Ping Chai, Zhang-Feng Wang, Wei-Ying Liang, Lei Chen, Dan Chen, An-Xun Wang, Zhao-Qiang Zhang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0061136
Abstract: This study was aimed to investigate the effect of combined cancer gene therapy with exogenous tumor necrosis factor-alpha (TNF-α) and cytosine deaminase (CD) suicide gene on laryngeal carcinoma cell line Hep-2 in vitro and in vivo. Transfection of the recombinant eukaryotic vectors of pcDNA3.1 (+) containing TNF-α and/or CD into Hep-2 cells resulted in expression of TNF-α and/or CD gene in vitro. The significant increase in apoptotic Hep-2 cells and decrease of Hep-2 cell proliferation were observed using 5-FC treatment combined with TNF-a expression by CD/5-FC suicide system. Moreover, bystander effect was also observed in the TNF-α and CD gene co-expression group. Laryngeal squamous cell carcinoma (LSCC) mice model was established by using BALB/c mice which different transfected Hep-2 cells with pcDNA3.1 (+) containing TNF-α and/or CD were applied subcutaneously. So these mice are divided into four groups, namely, Hep-2/TIC group; Hep-2/CD group; Hep-2/TNF-α group; Hep-2/0 group. At day 29 after cell inoculation, volume of grafted tumor had significant difference between each two of them (P<0.05). These results showed that the products of combined CD and TNF-α genes inhibited the growth of transplanted LSCC in mice model. So by our observed parameters and many others results, we hypothesized that 5-FC combined gene therapy with TNF-αand CD suicide gene should be an effective treatment on Laryngeal carcinoma.
Comparative study of SNP diversity and calculation of the effective size of population in chicken
鸡SNP多样性的比较研究与群体有效规模的估算

RAO You-Sheng,WANG Zhang-Feng,ZHOU Min,SHEN Xu,XIA Meng-Na,ZHANG Xi-Quan,
饶友生
,王樟凤,周敏,沈栩,夏梦娜,张细权

遗传 , 2007,
Abstract: A region (200 kb) of Contig. 060226.1 on GGA1 was selected to study the average diversity of Red Jungle Fowl (RJF), Taihe Silk chicken (TS), and White Recessive Rock (WRR), and estimate the effective population size (Ne) of chicken. The mean heterozygosities of RJF, TS and WRR were 0.28533+/-0.034747, 0.32926+/-0.039191 and 0.30168+/-0.040382, respectively. Significant test indicted that there is not significant difference between them (P=0.2368>0.05). The initial chicken effective population size was estimated to be about 20 000-150 000. Chicken has undergone serious population bottleneck effect during the first stage of domestication. However, this bottleneck effect did not result in a substantial loss of diversity as revealed by SNP. The possible explanations for similar SNP diversity between domesticated chicken and Red Jungle Fowl might due to many factors, such as a big Ne in earlier phase of domestication, population expending in breed differentiation, abroad crossing between breeds (especially crossing with RJF), together with high recombination rate in chicken genome.
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