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稀土钙钛矿型催化剂对CO催化氧化活性及表面氧种的研究 被引量:10
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作者 徐菁利 李树本 +3 位作者 李茸 马建泰 任家荣 兰劲松 《环境工程》 CAS CSCD 北大核心 2000年第5期57-59,共3页
研究了CO在不同催化剂La1 -xSrxMn1 -xBxO3(B =Fe、Ni、Cr)上的氧化反应活性 ,并利用程序升温热脱附(TPD)的方法对不同x值催化剂表面氧种及其含量的变化规律进行了考察 ,结合反应活性及表面吸附氧种随x值的变化规律 ,研究了催化剂对CO... 研究了CO在不同催化剂La1 -xSrxMn1 -xBxO3(B =Fe、Ni、Cr)上的氧化反应活性 ,并利用程序升温热脱附(TPD)的方法对不同x值催化剂表面氧种及其含量的变化规律进行了考察 ,结合反应活性及表面吸附氧种随x值的变化规律 ,研究了催化剂对CO氧化反应的活性与表面活性氧种的关系。 展开更多
关键词 钙钛矿 表面氧种 催化化活性 车用催化剂
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甲烷氧化偶联La-Me-O(Me=Mg,Ca,Sr,Ba)系催化剂表面氧种的研究 被引量:5
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作者 吴波 远松月 于作龙 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 1995年第3期432-436,共5页
利用CO_2-TPD法考察了La-Me-O(Me=Mg,Ca,Sr,Ba)系催化剂的表面碱性,并用O_2-TPD、CH_4-TPD法对该体系的表面活性氧种进行了表征,并与催化性能相关联。结果表明,La-Ba-O催化剂由... 利用CO_2-TPD法考察了La-Me-O(Me=Mg,Ca,Sr,Ba)系催化剂的表面碱性,并用O_2-TPD、CH_4-TPD法对该体系的表面活性氧种进行了表征,并与催化性能相关联。结果表明,La-Ba-O催化剂由于表面强碱性中心数目多,产生活性氧种的数目也多,有利于甲烷的活化,因而具有最高的甲烷转化率和C_2烃选择性。脉冲反应表明,在无气相氧存在下,表面晶格氧参与了氧化偶联,而且是选择氧化的活性氧种。 展开更多
关键词 甲烷 化偶联 催化剂 表面氧种 碱土金属
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氧化铈、氧化铜表面氧种的TPR研究 被引量:2
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作者 卢冠忠 汪仁 《化学通报》 CAS CSCD 北大核心 1993年第10期35-37,共3页
在氧化物催化的氧化还原反应中,催化刘表面上的氧物种对整个催化反应起着关键的作用,不同的表面氧物种将对氧化还原反应的产物产生影响。目前人们普遍认为的表面氧物种有:O_2、O_2^-、O^-和O_3^-(在低温时存在),它们的关系是:O_2(吸附)... 在氧化物催化的氧化还原反应中,催化刘表面上的氧物种对整个催化反应起着关键的作用,不同的表面氧物种将对氧化还原反应的产物产生影响。目前人们普遍认为的表面氧物种有:O_2、O_2^-、O^-和O_3^-(在低温时存在),它们的关系是:O_2(吸附)→O_2^-(吸附)→O^-(吸附) 展开更多
关键词 催化剂 化铈 化铜 表面氧种
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非化学计量氧化物CeO_(2-x)表面氧种的ESR研究 被引量:3
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作者 张效龙 詹瑞云 吴越 《科学通报》 EI CAS CSCD 北大核心 1990年第12期911-914,共4页
在氧化物表面上发生的催化氧化反应中,由分子氧活化形成的表面氧种起着十分重要的作用。目前,已确证的表面氧种有O^-,O_2^-,O_3^-,这主要归功于电子自旋共振(ESR)方法。
关键词 自由基 化铈 表面氧种 ESR
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低温甲烷氧化偶联Li-ZnO/La_2O_3催化剂 被引量:9
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作者 侯思聪 刘凌涛 寇元 《物理化学学报》 SCIE CAS CSCD 北大核心 2006年第8期1040-1042,共3页
采用浸渍法制备了Li-ZnO/La2O3催化剂并考察了其低温催化甲烷氧化偶联反应性能.反应条件下,在考察的w(Li)=2%和w(ZnO)=20%的Li-ZnO/La2O3在680℃得到了甲烷转化率为27.3%,C2选择性为65.2%,C2收率为17.8%的结果;在700℃,C2收率达到21.8%.... 采用浸渍法制备了Li-ZnO/La2O3催化剂并考察了其低温催化甲烷氧化偶联反应性能.反应条件下,在考察的w(Li)=2%和w(ZnO)=20%的Li-ZnO/La2O3在680℃得到了甲烷转化率为27.3%,C2选择性为65.2%,C2收率为17.8%的结果;在700℃,C2收率达到21.8%.Raman和XPS表征结果表明,催化剂低温催化性能与表面的活性吸附氧物种含量相关;La2O2CO3物种可能是提高催化剂的C2选择性的关键. 展开更多
关键词 甲烷化偶联 低温 Li-ZnO/La2O3 吸附氧种 La2O2CO3
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La_(1-x)Sr_xCo_(1-x)B_xO_3(B=Fe,Ni,Cr)催化CO氧化活性及其表面氧研究 被引量:3
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作者 李茸 马建泰 +1 位作者 周霞 苏致兴 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2000年第4期57-60,共4页
研究了 L a1-x Srx Co1-x Bx O3 (B=Fe,Ni,Cr)复合氧化物催化剂催化 CO氧化活性 ,并通过氧的程序升温热脱附 (TPD)研究了该类催化剂的表面氧 ,结合活性与表面氧随
关键词 化碳 催化 表面氧种 表面 催化剂
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一次性综合检测钢铁中O、N、H三种元素含量的惰性气体熔融测定方法验证研究 被引量:1
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作者 廖雅倩 《中国标准化》 2020年第10期222-226,共5页
高效、快速、准确地对钢铁及合金中O、N、H三种元素含量进行测定具有重要的意义。本文提出了钢铁及合金中O、N、H三种元素含量的一次性综合测定方法验证,主要从方法原理及设备、空白试验及校准、试样分析及时间、方法验证进行了分析研究。
关键词 一次性综合检测 氮氢三元素 惰性气体熔融 方法验证
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稀土钙钛矿型催化剂LaBO_3对NO_x催化性能及反应机理的研究(Ⅱ)──催化剂表面结构及N_2O催化分解反应机理 被引量:8
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作者 宋崇林 沈美庆 +1 位作者 王军 秦永宁 《燃烧科学与技术》 EI CAS CSCD 1999年第2期186-191,共6页
采用程序升温还原(TPR)和X-光电子能谱(XPS)技术研究了稀土钙钛矿型催化剂LaBO3上氧种的化学势、B位元素的平均价态及催化剂氧种的分布及种类,同时分析了N2O的分解反应机理。实验结果表明,B位离子平均价态升高... 采用程序升温还原(TPR)和X-光电子能谱(XPS)技术研究了稀土钙钛矿型催化剂LaBO3上氧种的化学势、B位元素的平均价态及催化剂氧种的分布及种类,同时分析了N2O的分解反应机理。实验结果表明,B位离子平均价态升高,氧离子的化学势增大,反应能力增强,催化活性较好;在LaBO3化合物上有两类氧种,即低能位的吸附氧和高能位的晶格氧,催化剂表面吸附氧对N2O分解有阻抑作用,CH4的加入能与表面吸附氧反应,提供氧空位,促进反应进行; 展开更多
关键词 钙钛矿化合物 氧种 催化剂 化物 催化分解
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Variation of soda content in fine alumina trihydrate by seeded precipitation 被引量:2
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作者 刘桂华 王鹏 +4 位作者 齐天贵 李小斌 田侣 周秋生 彭志宏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第1期243-249,共7页
High soda content in fine alumina trihydrate(ATH) limits its application and increases the soda consumption. The variation of soda content in the fine ATH by seeded precipitation was determined by detection of elect... High soda content in fine alumina trihydrate(ATH) limits its application and increases the soda consumption. The variation of soda content in the fine ATH by seeded precipitation was determined by detection of electric conductivity of solution, soda content in ATH, measurement of particle size distribution and microscopic analysis. The results show that high concentration of sodium aluminate solution, ground circulative seed, low temperature or fast initial precipitation rate increases the soda content in ATH. Soda mainly exists in lattice soda and less soda in desilication product (DSP) exists in the fine ATH precipitated from sodium aluminate solution with concentration of Al2O3 (ρAl2O3) more than 160 g/L and mass ratio of alumina to silica (μSiO2) of 400, and lattice soda decreases with increasing initial precipitation temperature, aging seed, and low precipitation rate and precipitation time. Results also imply that -+ 4)Na Al(OH ion-pair influences lattice soda content in ATH on the basis of electric conductivity variation. 展开更多
关键词 alumina trihydrate seeded precipitation soda content lattice soda sodium aluminate solution
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Seed Germination of Eggplant (Solanum melongena L.) Luba 2 Treated with Hydrogen Peroxide 被引量:3
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作者 孟淑春 崔彦玲 +1 位作者 邢宝田 刘玲 《Agricultural Science & Technology》 CAS 2014年第7期1117-1119,共3页
[Objective] This study aimed to investigate the effect of hydrogen peroxide on the seed germination of eggplant (Solanum melongena L.) Luba 2.[Method] The seeds of Luba 2 were separately soaked in 20%,40%,60% and... [Objective] This study aimed to investigate the effect of hydrogen peroxide on the seed germination of eggplant (Solanum melongena L.) Luba 2.[Method] The seeds of Luba 2 were separately soaked in 20%,40%,60% and 80% hydrogen peroxide solution for 2,5 and 10 min before seed germination.The germination rate and days to reach the maximum germination rate were calculated.[Result] Treatment with low concentrations (20%) of hydrogen peroxide for 2 and 5 min made eggplant Luba 2 germinate in advance,and shortened the time to reach the maximum germination rate.Treatment with high concentrations (60% and 80%) of hydrogen peroxide solution for longer time (10 min) caused significant damage to the seeds,delayed seed germination,and reduced the germination rate.[Conclusion] This study will provide theoretical references for the production practices of eggplant. 展开更多
关键词 Hydrogen peroxide Eggplant seeds Seed germination
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Effects of Nitric Oxide on the Germination of Wheat Seeds and Its Reactive Oxygen Species Metabolisms Under Osmotic Stress 被引量:51
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作者 张华 沈文飚 徐朗莱 《Acta Botanica Sinica》 CSCD 2003年第8期901-905,共5页
Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even t... Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even the elongation of radicle and plumule were dramatically promoted by SNP treatments during the germination under osmotic stress. Meanwhile, activities of amylase and EP were enhanced, thus leading to the degradation of storage reserve in seeds. After osmotic stress was removed, higher viability of wheat seeds was also maintained. In addition, the activities of CAT, APX and the content of proline were increased by SNP treatment simultaneously, but activities of LOX were inhibited, and both of which were beneficial for improving the antioxidant capacity during the germination of wheat seeds under osmotic stress. It was also shown that the increase of the activity of amylase induced by SNP in embryoless half-seeds of wheat in the beginning period of germination (6 h) might be indirectly related to GA(3). 展开更多
关键词 nitric oxide (NO) wheat seed germination osmotic stress storage reserve degradation reactive oxygen species metabolism gibberellin (GA(3))
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Effect of Allelochemicals of Chinese-fir root extracted by supercritical CO_2 extraction on Chinese fir 被引量:9
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作者 林思祖 曹光球 +1 位作者 杜玲 王爱萍 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期122-126,共5页
Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of se... Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of seed germination. The results showed thatas to the available rate of allelochemicals, the pressure and temperature of extraction were themost important factors. The allelochemicals of Chinese-fir root extracted by pure CO_2 and ethanolmixed with CO_2 have different allelopathic activities to seed germination, and the allelochemicalsextracted by ethanol mixed with CO_2 had stronger inhibitory effects on seed germination than thatextracted by pure CO_2. 展开更多
关键词 chinese fir autointoxication supercritical CO_2 extraction BIOASSAY SEEDGERMINATION
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Acidthiobacillus ferrooxidans中磁小体的提取(英文) 被引量:12
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作者 谢建平 刘新星 +1 位作者 刘文斌 邱冠周 《生物磁学》 2005年第3期7-10,共4页
At.f和趋磁细菌在生理特性和生长环境有一定的相似性,而且镜检发现At.f具有趋磁性,所以本文采用了趋磁细菌中磁小体的提取方法尝试提取At.f中的磁小体,用超声波破碎At.f后,以磁铁吸取其体内的磁性颗粒,经过检测,发现其体内确实存在含铁... At.f和趋磁细菌在生理特性和生长环境有一定的相似性,而且镜检发现At.f具有趋磁性,所以本文采用了趋磁细菌中磁小体的提取方法尝试提取At.f中的磁小体,用超声波破碎At.f后,以磁铁吸取其体内的磁性颗粒,经过检测,发现其体内确实存在含铁元素的磁性颗粒。提取粗样品经过电镜分析,证实其体内存在着少量由脂质包裹的磁小体。磁小体悬浮液经过蔗糖密度梯度离心纯化后,对其作透射电镜,可以清晰的看到磁小体。实验结果表明,At.f体内存在少量的磁小体,正是由于磁小体的存在,才使得At.f在外加磁场作用下发生磁生物效应。这是首次发现从酸性矿坑水分离的At.f具有趋磁性,并从中提取到了磁小体,可以利用At.f的趋磁性将其按照不同磁性进行分离,从而获得活性高的、对不同磁性矿物有特异性的高效浸矿菌种。 展开更多
关键词 磁小体 提取方法 趋磁细菌 生长环境 磁性矿物 生物电磁学
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Antioxidase Activities of Tetraploid Lines and Diploid Control Line of Chrysanthemum cinerariifolium 被引量:5
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作者 刘蓁 高山林 《Agricultural Science & Technology》 CAS 2009年第6期84-86,共3页
Objective The SOD, POD and APX enzyme activities of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium in test-tube and field were determined in order to provide a reference for the selective b... Objective The SOD, POD and APX enzyme activities of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium in test-tube and field were determined in order to provide a reference for the selective breeding of high resistance good tetraploid varieties of C. cinerariifolium. Method The SOD, POD and APX activities of each sample were determined. Every material should have 3 replicates which been determined and calculated mean value to analyze. Result The various kinds of antioxidase activities in protective enzyme system of tetraploid lines were increased generally in comparison with that of diploid control line. And there is certain relativity between the samples in field and in test-tube of these lines. Conclusion The antioxidase activities of each line in test-tube could be considered as reference index to screen high resistance good tetraploid varieties of C. cinerariifolium. 展开更多
关键词 Chrysanthemum cinerariifolium (Trev.) Vis. Antioxidase activities Selective breeding of good varieties
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Analysis of Protein and Isoenzyme of LiLum davidii var.unicolor,Lilium Asiatic Hybrids and Their Hybrid F_1 被引量:1
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作者 李雪 杨彩玲 +2 位作者 张鸣 霍彩霞 朱彦荣 《Agricultural Science & Technology》 CAS 2011年第1期54-57,共4页
[Objective]The paper was to provide theoretical basis for selection of parental combination and early identification of hybrids.[Method]The soluble protein and peroxidase of LiLum davidii var.unicolor,Lilium Asiatic h... [Objective]The paper was to provide theoretical basis for selection of parental combination and early identification of hybrids.[Method]The soluble protein and peroxidase of LiLum davidii var.unicolor,Lilium Asiatic hybrids and their filial generations were analyzed using polyacrylamide gel electrophoresis technique.[Result]The protein spectrum of filial generation with L.davidii var.unicolor as parent not only appeared the homologous band as parent with darker coloring,but also had new bands compared with parent.Peroxidase zymogram of hybrid F1 mainly displayed incomplete complementary and hybrid type of parent.[Conclusion]Protein spectrum and peroxidase zymogram could be used as the biochemical markers for the identification of hybrids of lily,which could also detect the target traits of plant. 展开更多
关键词 LiLum davidii var.unicolor Lilium Asiatic hybrids Hybrid F1 PROTEIN PEROXIDASE
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Remote ischemic perconditioning prevents liver transplantation-induced ischemia/reperfusion injury in rats: Role of ROS/RNS and e NOS 被引量:19
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作者 Ning He Jun-Jun Jia +10 位作者 Jian-Hui Li Yan-Fei Zhou Bing-Yi Lin Yi-Fan Peng Jun-Jie Chen Tian-Chi Chen Rong-Liang Tong Li Jiang Hai-Yang Xie Lin Zhou Shu-Sen Zheng 《World Journal of Gastroenterology》 SCIE CAS 2017年第5期830-841,共12页
AIM To investigate the underlying mechanisms of the protective role of remote ischemic perconditioning (RIPerC) in rat liver transplantation. METHODS Sprague-Dawley rats were subjected to sham, orthotopic liver transp... AIM To investigate the underlying mechanisms of the protective role of remote ischemic perconditioning (RIPerC) in rat liver transplantation. METHODS Sprague-Dawley rats were subjected to sham, orthotopic liver transplantation (OLT), ischemic postconditioning (IPostC) or RIPerC. After 3 h reperfusion, blood samples were taken for measurement of alanine aminotransferase, aspartate aminotransferase, creatinine (Cr) and creatinine kinase-myocardial band (CK-MB). The liver lobes were harvested for the following measurements: reactive oxygen species (ROS), H2O2, mitochondrial membrane potential (Delta psi m) and total nitric oxide (NO). These measurements were determined using an ROS/H2O2, JC1 and Total NOx Assay Kit, respectively. Endothelial NO synthase (eNOS) was analyzed by reverse transcription-polymerase chain reaction (RTPCR) and western blotting, and peroxynitrite was semiquantified by western blotting of 3-nitrotyrosine. RESULTS Compared with the OLT group, the grafts subjected to RIPerC showed significantly improved liver and remote organ functions (P < 0.05). ROS (P < 0.001) including H2O2 (P < 0.05) were largely elevated in the OLT group as compared with the sham group, and RIPerC (P < 0.05) reversed this trend. The collapse of Delta psi m induced by OLT ischemia/reperfusion (I/R) injury was significantly attenuated in the RIPerC group (P < 0.001). A marked increase of NO content and phosphoserine eNOS, both in protein and mRNA levels, was observed in liver graft of the RIPerC group as compared with the OLT group (P < 0.05). I/R-induced 3-nitrotyrosine content was significantly reduced in the RIPerC group as compared with the OLT group (P < 0.05). There were no significant differences between the RIPerC and IPostC groups for all the results except Cr. The Cr level was lower in the RIPerC group than in the IPostC group (P < 0.01). CONCLUSION Liver graft protection by RIPerC is similar to or better than that of IPostC, and involves inhibition of oxidative stress and up-regulation of the PI3K/Akt/eNOS/NO pathway. 展开更多
关键词 Liver transplantation Ischemia/reperfusion injury Remote ischemic perconditioning Endothelial nitric oxide synthase Reactive oxygen species
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Seed-induced synthesis of small-crystal TS-1 using ammonia as alkali source 被引量:11
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作者 薛腾 刘华萍 +3 位作者 王一萌 吴海虹 吴鹏 何鸣元 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期1928-1935,共8页
Small-crystal TS-1 was synthesized via a seed-induced approach using ammonia as the alkali source and tetrapropylammonium bromide as an auxiliary structure-directing agent. The TS-1 samples were characterized using X-... Small-crystal TS-1 was synthesized via a seed-induced approach using ammonia as the alkali source and tetrapropylammonium bromide as an auxiliary structure-directing agent. The TS-1 samples were characterized using X-ray diffraction, N2 adsorption-desorption, Fourier-transform infrared spectroscopy, inductively coupled plasma atomic emission spectroscopy, scanning electron microscopy, and ultraviolet-visible spectroscopy. The use of the colloidal seed reduced the crystal size, and an appropriate amount of silicalite-1 seed assisted Ti incorporation into the TS-1 framework. This method reduces the cost of TS- 1 synthesis because a significantly smaller amount of tetrapropylammonium hydroxide is used. The catalytic performance of the synthesized small-crystal TS-1 samples in cyclohexanone ammoximation was better than that of bulk TS-1 as a result of improved diffusion and a larger number of active tetrahedral Ti centers. 展开更多
关键词 Small crystal TS- 1 molecular sieve Seed-induced synthesis Ammonia Catalytic oxidation Cyclohexanone ammoximation
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Autophagic cell death induced by reactive oxygen species is involved in hyperthermic sensitization to ionizing radiation in human hepatocellular carcinoma cells 被引量:4
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作者 Guang-Jin Yuan Jun-Jian Deng +4 位作者 De-Dong Cao Lei Shi Xin Chen Jin-Ju Lei Xi-Ming Xu 《World Journal of Gastroenterology》 SCIE CAS 2017年第30期5530-5537,共8页
AIM To investigate whether autophagic cell death is involved in hyperthermic sensitization to ionizing radiation in human hepatocellular carcinoma cells, and to explore the underlying mechanism.METHODS Human hepatocel... AIM To investigate whether autophagic cell death is involved in hyperthermic sensitization to ionizing radiation in human hepatocellular carcinoma cells, and to explore the underlying mechanism.METHODS Human hepatocellular carcinoma cells were treated with hyperthermia and ionizing radiation. MTT and clonogenic assays were performed to determine cell survival. Cell autophagy was detected using acridine orange staining and flow cytometric analysis, and the expression of autophagy-associated proteins, LC3 and p62, was determined by Western blot analysis. Intracellular reactive oxygen species(ROS) were quantified using the fluorescent probe DCFH-DA.RESULTS Treatment with hyperthermia and ionizing radiation significantly decreased cell viability and surviving fraction as compared with hyperthermia or ionizing radiation alone. Cell autophagy was significantly increased after ionizing radiation combined with hyperthermia treatment, as evidenced by increased formation of acidic vesicular organelles, increased expression of LC3 II and decreased expression of p62. Intracellular ROS were also increased after combined treatment with hyperthermia and ionizing radiation. Pretreatment with N-acetylcysteine, an ROS scavenger, markedly inhibited the cytotoxicity and cell autophagy induced by hyperthermia and ionizing radiation.CONCLUSION Autophagic cell death is involved in hyperthermic sensitization of cancer cells to ionizing radiation, and its induction may be due to the increased intracellular ROS. 展开更多
关键词 Autophagic cell death HYPERTHERMIA Ionizing radiation Hepatocellular carcinoma Reactive oxygen species
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Anti-apoptotic effect of banhasasim-tang on chronic acid reflux esophagitis 被引量:4
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作者 Mi-Rae Shin Hyo-Jin An +1 位作者 Bu-Il Seo Seong-Soo Roh 《World Journal of Gastroenterology》 SCIE CAS 2017年第25期4644-4653,共10页
To evaluate the anti-apoptotic effect of banhasasim-tang (BHSST) on chronic acid reflux esophagitis (CARE) using a rat model. METHODSA surgically-induced CARE model was established in Sprague-Dawley rats. The modeled ... To evaluate the anti-apoptotic effect of banhasasim-tang (BHSST) on chronic acid reflux esophagitis (CARE) using a rat model. METHODSA surgically-induced CARE model was established in Sprague-Dawley rats. The modeled rats were divided into a treatment group or untreated group, and given BHSST (1 g/kg body weight per day) or water, respectively, for 15 consecutive days (n = 7 each group). Changes in expression of proteins related to nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and apoptosis were assessed by western blotting. Changes in esophageal pathology were analyzed by gross and histological examinations. RESULTSThe CARE exposure modeled rats showed increased levels of the NADPH oxidase subunit, NOX4 and p47<sup>phox</sup> in the esophagus. The BHSST treatment completely resolved these CARE-related increases. The CARE rats also showed markers of cytokine stress, including elevated levels of TNF-α and reactive oxygen species as well as of the consequent increase in JNK activation, and subsequent decrease in pro-survival gene expression, such as of Bcl-2. BHSST treatment resolved the CARE-related changes. BHSST also exerted an anti-apoptotic effect, as evidenced by altered expression of the apoptosis-related genes for bax, cytochrome c, and caspase 3. Finally, the BHSST treatment markedly ameliorated the CARE-related esophageal mucosal ulcerations. CONCLUSIONIn the rat model of CARE, BHSST can suppress development of esophageal mucosal ulceration via regulation of reactive oxygen species-dependent apoptosis. 展开更多
关键词 Banhasasim-tang Chronic acid reflux esophagitis Reactive oxygen species Esophageal ulcer APOPTOSIS
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Promotion effects of nickel-doped Al2O3-nanosheet-supported Au catalysts for CO oxidation 被引量:8
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作者 Rao Lu Lei He +2 位作者 Yang Wang Xin-Qian Gao Wen-Cui Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第2期350-356,共7页
Supported gold catalysts show high activity toward CO oxidation, and the nature of the support significantly affects the catalytic activity. Herein, serial Ni doping of thin porous Al2 O3 nanosheets was performed via ... Supported gold catalysts show high activity toward CO oxidation, and the nature of the support significantly affects the catalytic activity. Herein, serial Ni doping of thin porous Al2 O3 nanosheets was performed via a precipitation-hydrothermal method by varying the amount of Ni during the precipitation step. The prepared nanosheets were subsequently used as supports for the deposition of Au nanoparticles(NPs). The obtained Au/Nix Al catalysts were studied in the context of CO oxidation to determine the effect of Ni doping on the supports. Enhanced catalytic performances were obtained for the Au/Nix Al catalysts compared with those of the Au supported on bare Al2 O3. The Ni content and pretreatment atmosphere were both shown to influence the catalytic activity. Pretreatment under a reducing atmosphere was beneficial for improving catalytic activity. The highest activity was observed for the catalysts with a Ni/Al molar ratio of 0.05, achieving complete CO conversion at 20 °C with a gold loading of 1 wt%. The in-situ FTIR results showed that the introduction of Ni strengthened CO adsorption on the Au NPs. The H2-TPR and O2-TPD results indicated that the introduction of Ni produced new oxygen vacancies and allowed the oxygen molecules to be adsorbed and activated more easily. The improved catalytic performance after doping Ni was attributed to the smaller size of the Au NPs and more active oxygen species. 展开更多
关键词 ALUMINA Gold catalyst Nickel doping CO oxidation Oxygen activation
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