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Effect of AMPS(2-acrylamido-2-methylpropane sulfonic acid) content on the properties of polymer gels 被引量:2
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作者 Tian-Ci Zhang Ji-Jiang Ge +3 位作者 Hao Wu Hong-Bin Guo Bao-Lei Jiao Zhen Qian 《Petroleum Science》 SCIE CAS CSCD 2022年第2期697-706,共10页
The BST oilfield in the northwestern Taklamakan Desert is a fractured carbonate reservoir,but issues of water breakthrough are becoming increasingly severe with the development of water flooding.Unfortunately,the high... The BST oilfield in the northwestern Taklamakan Desert is a fractured carbonate reservoir,but issues of water breakthrough are becoming increasingly severe with the development of water flooding.Unfortunately,the high-temperature and high-salt conditions(130°C,71695 mg/L)of the BST oilfield pose challenges for the development of plugging agents.In this study,the effects of 2-acrylamido-2-methylpropane sulfonic acid(AMPS)content on AM/AMPS copolymers and gels were studied through viscosity measurements,nuclear magnetic resonance(NMR),and cryo-scanning electron microscope(Cryo-SEM).Moreover,the AMPS stabilization mechanism of the polymers and gels was explained.Heatresistant and salt-tolerant gel systems were developed,and their gelation properties,thermal stability,injection capacity,and plugging ability were evaluated.Experimental results showed inconsistencies between the effects of AMPS content on the polymers and gels.For the polymers,the thermal stability increased with increased AMPS content in the polymer.However,excessive AMPS content resulted in poor gelation and low strength.The developed gel systems with S30 polymer(AMPS content is approximately 26%)exhibited excellent thermal stability,controllable gelation time,good injection capacity,and plugging ability.The field application results indicated that most production wells had a positive response,with reduced water-cut and increased daily oil production. 展开更多
关键词 GELS 2-Acrylamido-2-methylpropane sulfonic acid Enhanced oil recovery HYDROLYSIS SYNERESIS
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Preparation and Acid Catalytic Activity of TiO2 Grafted Silica MCM-41 with Sulfate Treatment
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作者 Dai-shi Guo Zi-feng Ma +1 位作者 Chun-sheng Yin Qi-zhong Jiang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第1期21-26,共6页
TiO2 grafted silica MCM-41 catalyst with and without sulfate treatment were prepared. The structural and acid properties of these materials were investigated by XRD, N2 adsorption-desorption, element analysis, thermal... TiO2 grafted silica MCM-41 catalyst with and without sulfate treatment were prepared. The structural and acid properties of these materials were investigated by XRD, N2 adsorption-desorption, element analysis, thermal analysis, Raman and FTIR measurements. Their acid-catalytic activities were evaluated using the cyclization reaction of pseudoionone. It was found that the obtained materials possess well-ordered mesostructure, and the grafted TiO2 components were in highly dispersed amorphous form. T/MCM41 without sulfation contained only Lewis acid sites, while Brφnsted and Lewis acidities were remarkably improved for the sulfated materials ST/MCM41 and d-ST/MCM41. T/MCM-41 was not active for the cyclization reaction of pseudoionone, but ST/MCM-41 and d-ST/MCM-41 possessed favorable catalytic activities. The catalytic performance of ST/MCM-41 was comparable with that of the commercial solid acid catalyst of Amberlyst-15, and better than that of d-ST/MCM-41, although the latter underwent a second TiO2 grafting process and accordingly had higher Ti and S content. The specific surface structure of Si-O-Ti-O-S=O in ST/MCM-41 and the bilateral induction effect of Si and S=O on Si-O-Ti bonds were speculated to account for its higher acid catalytic activity. 展开更多
关键词 TiO2 grafting sulfate treatment Silica MCM-41 acid catalytic activity Cyclization of pseudoionone
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Solubilities of 2-Naphthalenesulfonic Acid Monohydrate and Sodium 2-Naphthalenesulfonate in Sulfuric Acid Solution and Their Application for Preparing Sodium 2-Naphthalenesulfonate
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作者 张凤宝 景晖 +4 位作者 朱文宇 张林 刘博 张国亮 夏清 《Transactions of Tianjin University》 EI CAS 2016年第3期273-278,共6页
The solubilities of 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate in sulfuric acid solutions were measured at temperatures ranging from 278,15 to 338.15 K by using a dynamic method. The conc... The solubilities of 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate in sulfuric acid solutions were measured at temperatures ranging from 278,15 to 338.15 K by using a dynamic method. The concentration of sulfuric acid solution ranged from 0 to 80wt%. The solubilities of 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate increased with temperature, and both of them were the lowest at 70wt% of sulfuric acid solution ( w3 0 = 0.70) while the highest in pure water. The solubility data were correlated by the modified Apelblat equation. Based on the solubility difference between 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate, a new technique in which sodium sulfate was used to replace sodium sulfite in the neutralization reaction was developed. The suitable mole ratio of H20 to Na2SO4 in the neutralization reaction was 80 : 1, and that of 2-naphthalenesulfonic acid monohydrate to Na2SO4 was 3.2 : 1. The material balance under the suitable mole ratios was given and discussed. 展开更多
关键词 2-naphthalenesulfonic acid monohydrate sodium 2-naphthalenesulfonate SOLUBILITY modified Apelblat equation sodium sulfate
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3,6-dichlorobenzo[b]thiophene-2-carboxylic acid alleviates ulcerative colitis by suppressing mammalian target of rapamycin complex 1 activation and regulating intestinal microbiota
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作者 Qiong-Zi He Peng Wei +5 位作者 Jun-Zhi Zhang Tong-Tong Liu Kun-Qun Shi Huan-Huan Liu Jing-Wei Zhang Shi-Jia Liu 《World Journal of Gastroenterology》 SCIE CAS 2022年第46期6522-6536,共15页
BACKGROUND 3,6-dichlorobenzo[b]thiophene-2-carboxylic acid(BT2)is a benzothiophene carboxylate derivative that can suppress the catabolism of branched-chain amino acid(BCAA)-associated mammalian target of rapamycin co... BACKGROUND 3,6-dichlorobenzo[b]thiophene-2-carboxylic acid(BT2)is a benzothiophene carboxylate derivative that can suppress the catabolism of branched-chain amino acid(BCAA)-associated mammalian target of rapamycin complex 1(mTORC1)activation.Previous studies have demonstrated the therapeutic effects of BT2 on arthritis,liver cancer,and kidney injury.However,the effects of BT2 on ulcerative colitis(UC)are unknown.AIM To investigate the anti-UC effects of BT2 and the underlying mechanism.METHODS Mouse UC models were created through the administration of 3.5%dextran sodium sulfate(DSS)for 7 d.The mice in the treated groups were administered salazosulfapyridine(300 mg/kg)or BT2(20 mg/kg)orally from day 1 to day 7.At the end of the study,all of the mice were sacrificed,and colon tissues were removed for hematoxylin and eosin staining,immunoblot analyses,and immunohistochemical assays.Cytokine levels were measured by flow cytometry.The contents of BCAAs including valine,leucine,and isoleucine,in mouse serum were detected by liquid chromatography-tandem mass spectrometry,and the abundance of intestinal flora was analyzed by 16S ribosomal DNA sequencing.RESULTS Our results revealed that BT2 significantly ameliorated the inflammatory symptoms and pathological damage induced by DSS in mice.BT2 also reduced the production of the proinflammatory cytokines interleukin 6(IL-6),IL-9,and IL-2 and increased the anti-inflammatory cytokine IL-10 level.In addition,BT2 notably improved BCAA catabolism and suppressed mTORC1 activation and cyclooxygenase-2 expression in the colon tissues of UC mice.Furthermore,highthroughput sequencing revealed that BT2 restored the gut microbial abundance and diversity in mice with colitis.Compared with the DSS group,BT2 treatment increased the ratio of Firmicutes to Bacteroidetes and decreased the abundance of Enterobacteriaceae and Escherichia-Shigella.CONCLUSION Our results indicated that BT2 significantly ameliorated DSS-induced UC and that the latent mechanism involved the suppression of BCAA-associated mTORC1 activation and modulation of the intestinal flora. 展开更多
关键词 3 6-dichlorobenzo[b]thiophene-2-carboxylic acid Ulcerative colitis Mechanistic target of rapamycin complex 1 Intestinal flora Dextran sodium sulfate Cyclooxygenase-2
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L-四氢噻唑-2-硫酮-4-羧酸乙酯的合成 被引量:1
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作者 黄化民 李叶芝 +4 位作者 胡学山 田颜青 郎美东 李惟 王玉宏 《吉林大学自然科学学报》 CAS CSCD 1993年第1期119-120,共2页
在硫酸铁水合物催化下由L-四氢噻唑-2-硫酮-4-羧酸与乙醇反应得到L-四氢噻唑-2-硫酮-4-羧酸乙酯.
关键词 四氢噻唑 硫酮 羟酸乙酯 合成
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Fe_2(SO_4)_3/SiO_2催化合成环己酮1,2—丙二醇缩酮 被引量:2
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作者 任立国 张晓丽 余济伟 《辽宁石油化工大学学报》 CAS 2010年第1期37-40,共4页
采用溶胶-胶凝法和浸渍法制备了二氧化硅负载的硫酸铁[Fe_2(SO_4)_3/SiO_2]固体酸催化剂,以环己酮和1,2-丙二醇为原料,在无溶剂条件下合成了环己酮1,2-丙二醇缩酮。考察了Fe_2(SO_4)_3/SiO_2固体酸催化剂的焙烧温度、Fe_2(SO_4)_3在SiO_... 采用溶胶-胶凝法和浸渍法制备了二氧化硅负载的硫酸铁[Fe_2(SO_4)_3/SiO_2]固体酸催化剂,以环己酮和1,2-丙二醇为原料,在无溶剂条件下合成了环己酮1,2-丙二醇缩酮。考察了Fe_2(SO_4)_3/SiO_2固体酸催化剂的焙烧温度、Fe_2(SO_4)_3在SiO_2上的负载量、醇酮物质的量比、催化剂质量和反应时间等因素对产品收率的影响。实验结果表明,Fe_2(SO_4)_3/SiO_2固体酸是合成环己酮1,2-丙二醇缩酮的理想催化剂,较适宜的反应条件为:催化剂的焙烧温度300℃、Fe_2(SO_4)_3在SiO_2上的负载量20%、环己酮与1,2-丙二醇的物质的量比1:1、催化剂质量分数5%和反应时间70 min。在此条件下,环己酮1,2-丙二醇缩酮收率达到98.21%。Fe_2(SO_4)_3/SiO_2催化剂具有良好的稳定性,重复使用5次后环己酮1,2-丙二醇缩酮的收率为88.90%。 展开更多
关键词 溶胶-胶凝 硫酸铁 固体酸 缩酮化反应 环己酮1 2-丙二醇缩酮
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2,3-环氧丙磺酸钠催化合成与表征 被引量:8
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作者 张荣明 马喜凤 《河北化工》 2007年第1期10-11,共2页
以环氧氯丙烷、亚硫酸氢钠为原料,采用两步法合成2,3-环氧丙磺酸钠;考察了催化剂、溶剂、反应温度对反应的影响。通过条件和正交实验得出最佳反应条件:反应温度55℃,磷酸钠与3-氯-2-羟基丙磺酸钠为1∶(1摩尔比)时,每0.1mol反应物加50mL... 以环氧氯丙烷、亚硫酸氢钠为原料,采用两步法合成2,3-环氧丙磺酸钠;考察了催化剂、溶剂、反应温度对反应的影响。通过条件和正交实验得出最佳反应条件:反应温度55℃,磷酸钠与3-氯-2-羟基丙磺酸钠为1∶(1摩尔比)时,每0.1mol反应物加50mL水。在最佳反应条件下,收率达85%以上。 展开更多
关键词 3-氯-2-羟基丙磺酸钠 2 3-环氧丙磺酸钠 合成 催化剂
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2-(9-蒽基)-2-羟基乙酸的毛细管电泳分离研究 被引量:3
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作者 杜丽丽 王伟 +2 位作者 李宝林 李锦 温俊峰 《分析科学学报》 CAS CSCD 2006年第2期202-204,共3页
以β-环糊精及其衍生物为手性选择试剂,采用高效毛细管电泳法对外消旋的2-(9-蒽基)-2-羟基乙酸进行了手性分离。研究了手性选择剂的种类、浓度,背景电解质的pH值等因素对对映体分离的影响。实验结果表明,采用55 g/L的磺化-β-环糊精为... 以β-环糊精及其衍生物为手性选择试剂,采用高效毛细管电泳法对外消旋的2-(9-蒽基)-2-羟基乙酸进行了手性分离。研究了手性选择剂的种类、浓度,背景电解质的pH值等因素对对映体分离的影响。实验结果表明,采用55 g/L的磺化-β-环糊精为手性选择试剂,在pH 2.5的10 mmol/L三羟甲基氨基甲烷(Tris)-磷酸缓冲体系中,2-(9-蒽基)-2-羟基乙酸对映体可得到良好的分离。 展开更多
关键词 毛细管电泳 手性分离 2-(9-蒽基)-2-羟基乙酸 磺化-β-环糊精
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2,4,6-三硝基苯磺酸和葡聚糖硫酸钠诱导的大鼠肠炎模型比较 被引量:3
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作者 曾健梅 黄敏聪 +2 位作者 李杨玲 张博 林能明 《中国药房》 CAS 北大核心 2017年第10期1353-1357,共5页
目的:比较2,4,6-三硝基苯磺酸(TNBS)和葡聚糖硫酸钠(DSS)诱导的两种肠炎大鼠模型。方法:SD大鼠随机分为正常对照组、TNBS模型组和DSS模型组,每组10只。TNBS模型组大鼠采用TNBS 50%乙醇溶液以100 mg/kg一次性灌肠法建立肠炎模型,DSS模型... 目的:比较2,4,6-三硝基苯磺酸(TNBS)和葡聚糖硫酸钠(DSS)诱导的两种肠炎大鼠模型。方法:SD大鼠随机分为正常对照组、TNBS模型组和DSS模型组,每组10只。TNBS模型组大鼠采用TNBS 50%乙醇溶液以100 mg/kg一次性灌肠法建立肠炎模型,DSS模型组大鼠采用4%DSS水溶液连续7 d自由饮用建立肠炎模型。观察各组大鼠一般情况,检测血清总胆固醇(TC)和三酰甘油(TG)含量、结肠长度及质量、结肠组织中髓过氧化物酶(MPO)活性,肉眼观察结肠大体外观形态,苏木精-伊红染色观察结肠病理学变化。结果:与正常对照组比较,TNBS模型组大鼠体质量明显减轻,结肠长度明显缩短、单位长度质量明显增加,粪便性状评分、血清TG含量、MPO活性、结肠大体外观评分和病理学评分均明显增加(P<0.05或P<0.01);DSS模型组大鼠体质量明显减轻,结肠长度明显缩短,粪便性状和结肠病理学评分均明显增加(P<0.05或P<0.01)。与DSS模型组比较,TNBS模型组大鼠结肠长度明显缩短、单位长度质量明显增加,血清TC、TG含量和结肠大体外观评分、病理学评分明显增加(P<0.05或P<0.01),组织病理学检查可见明显肠道溃疡与粘连。结论:DSS诱导肠炎模型大鼠粪便评分较TNBS诱导模型低,TNBS诱导肠炎模型大鼠在肠道组织损伤方面较DSS诱导模型更严重、恢复更慢。 展开更多
关键词 2 4 6-三硝基苯磺酸 葡聚糖硫酸钠 结肠炎 大鼠 5-氨基水杨酸
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Solvent extraction of zinc from zinc sulfate solution 被引量:2
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作者 龙怀中 柴立元 +1 位作者 覃文庆 唐双华 《Journal of Central South University》 SCIE EI CAS 2010年第4期760-764,共5页
The extraction of zinc from zinc sulfate solution was investigated, using 20% saponified D2EHPA as an extractam and 260^# sulfonate kerosene as a diluent. The solution was stirred for 8 min at phase ratio (Vσ/Va) o... The extraction of zinc from zinc sulfate solution was investigated, using 20% saponified D2EHPA as an extractam and 260^# sulfonate kerosene as a diluent. The solution was stirred for 8 min at phase ratio (Vσ/Va) of 1.0:1.0, initial pH of 2.0 and stirring speed of 200 r/min. The results show that 75% zinc can be extracted from the zinc sulfate solution when the concentration of zinc is 18.7 g/L after being settled for 10 min. 88.60% zinc can be stripped by 196 g/L sulfuric acid, and zinc ion can be separated from ferric ion. 展开更多
关键词 zinc sulfate solution saponified bi(2-ethylhexyl) phosphoric acid (D2EHPA) ZINC solvent extraction
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衣康酸/2-丙烯酰胺-2-甲基丙磺酸共聚物性能研究 被引量:1
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作者 郝敬相 石文艳 《广州化工》 CAS 2022年第15期94-96,120,共4页
采用静态阻垢法,评价了衣康酸/2-丙烯酰胺-2-甲基丙磺酸(IA/AMPS)共聚物对碳酸钙、硫酸钙、磷酸钙的阻垢性能以及温度对IA/AMPS共聚物阻垢性能的影响。结果表明:随着加药量增加,阻垢率升高,最终趋于平稳。加药量为20 mg/L时,IA/AMPS共... 采用静态阻垢法,评价了衣康酸/2-丙烯酰胺-2-甲基丙磺酸(IA/AMPS)共聚物对碳酸钙、硫酸钙、磷酸钙的阻垢性能以及温度对IA/AMPS共聚物阻垢性能的影响。结果表明:随着加药量增加,阻垢率升高,最终趋于平稳。加药量为20 mg/L时,IA/AMPS共聚物对碳酸钙和硫酸钙的阻垢率分别达到88.28%和96.9%;在加药量为16 mg/L时,该药剂对磷酸钙的阻垢率达到93%。温度升高,IA/AMPS共聚物的阻垢率稍有下降,该药剂具有一定的耐温性。 展开更多
关键词 静态阻垢法 衣康酸/2-丙烯酰胺-2-甲基丙磺酸 硫酸钙垢 阻垢效率
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SO_(4)^(2-)/M_(x)O_(y)型固体酸抗硫流失的稳定性研究进展
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作者 吴臻煜 佘洁 +4 位作者 马娜 索娜 高尔东 李倩倩 李力成 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2023年第6期1453-1463,共11页
SO_(4)^(2-)/M_(x)O_(y)型固体酸催化剂具有酸强度高、制备方法简便、成本低、无腐蚀性等优点,但其在催化反应过程中却表现出稳定性差、易失活的问题,严重地限制了其大规模应用。硫物种流失是造成SO_(4)^(2-)/M_(x)O_(y)型固体酸失活的... SO_(4)^(2-)/M_(x)O_(y)型固体酸催化剂具有酸强度高、制备方法简便、成本低、无腐蚀性等优点,但其在催化反应过程中却表现出稳定性差、易失活的问题,严重地限制了其大规模应用。硫物种流失是造成SO_(4)^(2-)/M_(x)O_(y)型固体酸失活的最主要原因。硫物种与载体间的S—O—M键受到水的影响而容易发生断裂,进而使得硫物种浸出、脱落,造成固体酸的酸强度降低和酸量减少。调研了关于SO_(4)^(2-)/M_(x)O_(y)型固体酸抗硫流失的稳定性研究进展文献的基础上,针对其结构设计、表面调控和技术改进3方面进行概述,并展望了未来研究方向。 展开更多
关键词 SO_(4)^(2-)/M_(x)O_(y) 固体酸 稳定性 失活 流失 硫物种
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Introduction manner of sulfate acid for improving the performance of SO_4^(2–)/CeO_2 on selective catalytic reduction of NO by NH_3 被引量:10
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作者 宋忠贤 张秋林 +3 位作者 宁平 刘昕 樊洁 黄真真 《Journal of Rare Earths》 SCIE EI CAS CSCD 2016年第7期667-674,共8页
A series of sulfated CeO2 catalysts were synthesized by impregnation and sol-gel methods and used for selective catalytic reduction (SCR) of NOx by NH3. The results showed that the sulfated CeO2 catalysts prepared b... A series of sulfated CeO2 catalysts were synthesized by impregnation and sol-gel methods and used for selective catalytic reduction (SCR) of NOx by NH3. The results showed that the sulfated CeO2 catalysts prepared by sol-gel method showed excellent catalytic activity at 150-50 ℃, and more than 90% NOx conversion was obtained at 232-450 ℃ with a gas hourly space velocity of 60000 h-1. The catalysts were characterized by X-ray diffraction (XRD), N2 adsorption, Raman, thermogravimetry (TG), H2-tem- perature-programmed reduction (H2-TPR) and Py-infrared spectroscopy (Py-IR). The excellent SCR performance was associated with the surface acidity and the micro-structure. The introduction of sulfate acid into CeO2 could increase the amount of BrOnsted and Lewis acid sites over the catalysts, resulting in the improvement of the low temperature activity. The sulfated CeO2 catalysts prepared by sol-gel method possessed lower crystallization degree, excellent redox property and larger specific surface areas, which were responsible for the superior SCR performance. 展开更多
关键词 sulfated CeO2 selective catalytic reduction surface acidity MICRO-STRUCTURE rare earthsO
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Roles of Lewis and Brnsted acid sites in NO reduction with ammonia on CeO_2-ZrO_2-NiO-SO_4^(2-) catalyst 被引量:12
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作者 司知蠢 翁端 +1 位作者 吴晓东 江洋 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第5期727-731,共5页
Nickel and sulfate co-modified CeO2-ZrO2 catalysts were prepared by sol-gel method. The catalysts were characterized by XRD, FTIR, XPS, NH3 chemisorption and NH3-SCR activity tests. The results showed that the enhance... Nickel and sulfate co-modified CeO2-ZrO2 catalysts were prepared by sol-gel method. The catalysts were characterized by XRD, FTIR, XPS, NH3 chemisorption and NH3-SCR activity tests. The results showed that the enhanced acidity of CeO2-ZrO2 catalysts by nickel and sulfate co-modification was responsible for the broadened temperature window and improved the selectivity to N2 in NH3-SCR deNOx. The introduction of nickel to CeO2-ZrO2 solid solutions resulted in more Ce3+ on surface of catalyst, leading to an in... 展开更多
关键词 CEO2-ZRO2 nickel sulfate acid sites rare earths
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Sulfation of chondroitin and bile acids converges to antagonize Wnt/β-catenin signaling and inhibit APC deficiency-induced gut tumorigenesis
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作者 Pengfei Xu Yue Xi +7 位作者 Jong-Won Kim Junjie Zhu Min Zhang Meishu Xu Songrong Ren Da Yang Xiaochao Ma Wen Xie 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2024年第3期1241-1256,共16页
Sulfation is a crucial and prevalent conjugation reaction involved in cellular processes and mammalian physiology.3’-Phosphoadenosine 5’-phosphosulfate(PAPS)synthase 2(PAPSS2)is the primary enzyme to generate the un... Sulfation is a crucial and prevalent conjugation reaction involved in cellular processes and mammalian physiology.3’-Phosphoadenosine 5’-phosphosulfate(PAPS)synthase 2(PAPSS2)is the primary enzyme to generate the universal sulfonate donor PAPS.The involvement of PAPSS2-mediated sulfation in adenomatous polyposis coli(APC)mutation-promoted colonic carcinogenesis has not been reported.Here,we showed that the expression of PAPSS2 was decreased in human colon tumors along with cancer stages,and the lower expression of PAPSS2 was correlated with poor prognosis in advanced colon cancer.Gut epithelial-specific heterozygous Apc deficient and Papss2-knockout(Apc^(Δgut-Het)Papss2^(Δgut))mice were created,and the phenotypes were compared to the spontaneous intestinal tumorigenesis of Apc^(Δgut-Het)mice.Apc^(Δgut-Het)Papss2^(Δgutmice) were more sensitive to gut tumorigenesis,which was mechanistically accounted for by the activation of Wnt/β-catenin signaling pathway due to the suppression of chondroitin sulfation and inhibition of the farnesoid X receptor(FXR)-transducin-like enhancer of split 3(TLE3)gene regulatory axis.Chondroitin sulfate supplementation in Apc^(Δgut-Het)Papss2^(Δgutmice) alleviated intestinal tumorigenesis.In summary,we have uncovered the protective role of PAPSS2-mediated chondroitin sulfation and bile acids-FXR-TLE3 activation in the prevention of gut carcinogenesis via the antagonization of Wnt/β-catenin signaling.Chondroitin sulfate may be explored as a therapeutic agent for Papss2 deficiency-associated colonic carcinogenesis. 展开更多
关键词 Colon cancer APC Wnt/b-catenin PAPSS2 Chondroitin sulfate sulfatION Bile acids FXR
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壳聚糖和丙烯酰胺基甲基丙磺酸接枝共聚及表征 被引量:9
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作者 丁德润 刘鸿志 《精细化工》 EI CAS CSCD 北大核心 2004年第1期72-75,共4页
以硫酸铈铵为引发剂,醋酸为溶剂,用2 丙烯酰胺基 2 甲基丙磺酸(AMPS)与壳聚糖(CTS)制备CTS-AMPS接枝改性产品。正交实验优化出较佳的工艺条件为:反应时间3h,反应温度40℃,m(CTS)∶m(AMPS)=1∶5,引发剂用量5g(相对于1g壳聚糖)。用IR和X... 以硫酸铈铵为引发剂,醋酸为溶剂,用2 丙烯酰胺基 2 甲基丙磺酸(AMPS)与壳聚糖(CTS)制备CTS-AMPS接枝改性产品。正交实验优化出较佳的工艺条件为:反应时间3h,反应温度40℃,m(CTS)∶m(AMPS)=1∶5,引发剂用量5g(相对于1g壳聚糖)。用IR和X射线衍射对产物进行了表征。 展开更多
关键词 壳聚糖 2-丙烯酰胺基-2-甲基丙磺酸 硫酸铈铵 接枝共聚
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产酸脱硫反应器中碳硫比对群落生态特征的影响 被引量:22
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作者 任南琪 王爱杰 《环境科学》 EI CAS CSCD 北大核心 2002年第4期52-56,共5页
通过产酸脱硫反应器处理高浓度含硫酸盐废水的连续流试验 ,从群落动态的角度研究碳硫比 (COD/SO2 - 4)从 4 2降低到 2 0的过程中 ,pH值、氧化还原电位 (ORP)、碱度 (ALK)和末端产物 (VFAs)组成、优势种群分布等群落生态特征的变化规律 ... 通过产酸脱硫反应器处理高浓度含硫酸盐废水的连续流试验 ,从群落动态的角度研究碳硫比 (COD/SO2 - 4)从 4 2降低到 2 0的过程中 ,pH值、氧化还原电位 (ORP)、碱度 (ALK)和末端产物 (VFAs)组成、优势种群分布等群落生态特征的变化规律 .试验证明 ,在此过程中ORP和ALK提高 ,而 pH值和VFAs中乙酸的分布比例降低 ,群落类型由高碳硫比稳定型转化为低碳硫比亚稳定型 。 展开更多
关键词 产酸脱硫反应器 碳硫比 群落生态特征 硫酸盐 废水处理
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改性聚天冬氨酸共聚物的合成及其阻硫酸钙垢性能的研究 被引量:14
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作者 赵彦生 李一清 彭璐 《化学与生物工程》 CAS 2011年第3期81-84,共4页
以马来酸酐(MA)、氨水、柠檬酸(CA)和牛磺酸(AES)为原料,在水体系中采用热缩聚方法制备了一种含有羧基、磺酸基和羟基的聚琥珀酰亚胺共聚物中间体(SHPSI),经碱解得到改性的聚天冬氨酸(PASP)共聚物(SHPASP)。探讨了牛磺酸用量、反应温度... 以马来酸酐(MA)、氨水、柠檬酸(CA)和牛磺酸(AES)为原料,在水体系中采用热缩聚方法制备了一种含有羧基、磺酸基和羟基的聚琥珀酰亚胺共聚物中间体(SHPSI),经碱解得到改性的聚天冬氨酸(PASP)共聚物(SHPASP)。探讨了牛磺酸用量、反应温度及反应时间对SHPASP阻硫酸钙垢性能的影响。确定SHPASP的最佳合成条件为:n(MA)∶n(AES)=1∶0.050,反应温度180℃,反应时间2 h。当SHPASP用量为8 mg.L-1时,其对硫酸钙的阻垢率达到100%。采用红外光谱对SHPASP结构进行了表征;通过XRD对SHPASP阻硫酸钙垢的结构进行分析,结果表明,SHPASP的加入对硫酸钙垢晶体的生长起到了抑制作用。 展开更多
关键词 聚天冬氨酸 牛磺酸 共聚物 硫酸钙 阻垢性能
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零价铁活化过硫酸钠降解2-萘磺酸 被引量:6
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作者 贾冬梅 万立之 +1 位作者 姚海波 李长海 《环境工程》 CAS CSCD 北大核心 2016年第9期9-12,共4页
近几年来,基于SO-4·的新型高级氧化技术逐渐成为水处理领域的研究热点。利用零价铁活化过硫酸钠产生SO-4·对水溶液中2-萘磺酸开展了降解研究。考察了零价铁投加量、过硫酸钠浓度、温度、p H值、腐殖酸、富里酸、硫酸盐及2-萘... 近几年来,基于SO-4·的新型高级氧化技术逐渐成为水处理领域的研究热点。利用零价铁活化过硫酸钠产生SO-4·对水溶液中2-萘磺酸开展了降解研究。考察了零价铁投加量、过硫酸钠浓度、温度、p H值、腐殖酸、富里酸、硫酸盐及2-萘磺酸初始浓度对2-萘磺酸降解效果的影响。结果表明:温度升高,酸性或中性环境下有利于2-萘磺酸的降解;零价铁投加量为0.1 g/L、过硫酸钠浓度为3.0 mmol/L时,2-萘磺酸的降解率高达96.8%;腐殖酸和富里酸的存在有利于2-萘磺酸降解,硫酸钠的存在会抑制2-萘磺酸降解。研究表明:采用零价铁活化过硫酸盐降解技术去除水溶液中2-萘磺酸具有广阔的应用前景。 展开更多
关键词 2-萘磺酸 零价铁 过硫酸盐 氧化 硫酸根自由基
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硫酸氧钛液相法制备纳米二氧化钛 被引量:5
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作者 郑典模 陈早明 陈喜蓉 《无机盐工业》 CAS 北大核心 2005年第3期17-19,共3页
以硫酸氧钛为原料,液相法在水醇体系中制备纳米二氧化钛.讨论了表面活性剂、硫酸氧钛浓度、反应温度、体系pH、煅烧温度等因素对纳米粒子生成及性能的影响,用X射线衍射仪和透射电镜检测,证明实验获得的产物为粒径20~40nm的锐钛型二氧化... 以硫酸氧钛为原料,液相法在水醇体系中制备纳米二氧化钛.讨论了表面活性剂、硫酸氧钛浓度、反应温度、体系pH、煅烧温度等因素对纳米粒子生成及性能的影响,用X射线衍射仪和透射电镜检测,证明实验获得的产物为粒径20~40nm的锐钛型二氧化钛.研究表明,通过改变工艺条件可控制纳米二氧化钛粒径及尺寸分布.工艺流程简单,制备成本低,易实现工业化. 展开更多
关键词 二氧化钛 硫酸氧钛 硫酸
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