期刊文献+
共找到9篇文章
< 1 >
每页显示 20 50 100
Electron-deficient Cu site catalyzed acetylene hydrochlorination
1
作者 Bolin wang Chunxiao Jin +7 位作者 Shujuan Shao Yuxue Yue Yuteng Zhang saisai wang Renqin Chang Haifeng Zhang Jia Zhao Xiaonian Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第4期1128-1140,共13页
Rational design of catalytic sites to activate the C≡C bond is of paramount importance to advance acetylene hydrochlorination. Herein, Cu sites with electron-rich and electron-deficient states were constructed by con... Rational design of catalytic sites to activate the C≡C bond is of paramount importance to advance acetylene hydrochlorination. Herein, Cu sites with electron-rich and electron-deficient states were constructed by controlling the impregnation solutions. The π electrons flowing from acetylene to Cu site are facilitated over the electron-deficient Cu sites, achieving high activation of C≡C bond. The contradiction between the increased activation of acetylene required for enhanced catalytic activity and the resistance of Cu site to reduction by acetylene required for maintaining catalytic stability can be balanced by establishing strong interactions of Cu site with pyrrolic-N species. The catalytic activity displays a volcano shape scaling relationship as a function of Cu particle size. Tribasic copper chloride is concomitantly generated with the construction of electron-deficient Cu sites. The H–Cl bond of HCl can be activated over the tribasic copper chloride, accelerating the surface reaction of vinyl chloride production. This strategy of inducing electron deficiency provides new insight into the rational design of catalysts for the synthesis of vinyl chloride with a high catalytic performance. 展开更多
关键词 C≡C bond Acetylene hydrochlorination Cu sites Tribasic copper chloride ELECTRON-DEFICIENT
下载PDF
乙炔氢氯化反应中的负载金-离子液体催化剂:离子态金物种的稳定机制 被引量:5
2
作者 赵佳 王赛赛 +9 位作者 王柏林 岳玉学 金春晓 陆金跃 方正 庞祥雪 丰枫 郭伶伶 潘志彦 李小年 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第2期334-346,共13页
聚氯乙烯(PVC)作为世界通用工程塑料之一,具有优异的物理、化学和机械性能,在工业、农业、建筑、包装、电力等行业中应用广泛.氯乙烯是生产聚氯乙烯的重要单体.氯乙烯的生产主要有电石法和乙烯法两种工艺路线,由于我国“贫油、富煤、少... 聚氯乙烯(PVC)作为世界通用工程塑料之一,具有优异的物理、化学和机械性能,在工业、农业、建筑、包装、电力等行业中应用广泛.氯乙烯是生产聚氯乙烯的重要单体.氯乙烯的生产主要有电石法和乙烯法两种工艺路线,由于我国“贫油、富煤、少气”的资源现状,电石法产能占全部产能的83%以上.电石法生产氯乙烯的原理是在氯化汞催化剂存在下,将电石水解精制后的乙炔气与氯化氢加成直接合成氯乙烯.随着节能减排及环保要求的逐渐提高和国际涉汞公约的实施,开发新一代绿色无汞催化剂具有重要的战略意义.近年来,金基催化剂是无汞催化剂基础研究和技术开发中最重要的方向.在之前的工作中,我们课题组首先报道了负载离子液体-金催化剂体系(Au-SILP)在电石法生产氯乙烯工艺中的应用,并发现离子液体的存在可以显著提高金活性物种在载体表面的分散度和稳定其化学价态.在后续研究中,我们在负载离子液体-金催化体系中引入金属铜离子(Cu^2+),利用反应过程中Au-Cu之间的氧化还原循环,设计并制备了金属铜基配位离子液体,构建了负载离子液体-金-铜催化剂体系.铜离子的引入形成了一个催化剂自身维持氧化态的微环境,实现了被还原金物种的原位氧化再生.本文在上述研究基础上,利用配位离子液体[Bmim][N(CN)2]中[N(CN)2^–]阴离子和阳离子金之间的强配位作用,构建出比Au-Cl键更稳定的Au–N键,并通过X射线光电子能谱(XPS)、球差校正-扫描透射电镜(AC-STEM)和扩展X射线吸收精细结构(EXAFS)表征证明了Au以单原子状态存在于载体表面.制备的Au-N(CN)2/AC催化剂在乙炔氢氯化反应中表现出比Au-Cl/AC和Au/AC催化剂更高的稳定性和催化活性以及更短的诱导期.进一步表征分析发现,[N(CN)2^–]配体促进了阳离子金和配体之间的电子转移,提高了阳离子金的电子云密度,削弱了乙炔在阳离子金上的吸附强度,抑制了其还原,提高了催化剂的稳定性.更重要的是,与阳离子金配位的[N(CN)2^–]配体使得反应过程中的氯化氢在氮位点发生化学解离,促进了氯化氢活化,同时降低了反应能垒.对负载配位离子液体-金催化体系反应诱导期的分析结果表明,反应诱导期与反应物(乙炔、氯化氢)分子在离子液体层中的溶解度无关,而主要取决于催化剂中Au(Ⅲ)物种的含量和反应物分子在离子液体中的扩散速率.上述研究结果进一步深化了离子液体和活性金物种之间电子的作用机理,建立了负载离子液体-金催化剂体系对反应物的活化机制和反应机理,为进一步开发具有工业应用价值的乙炔氢氯化反应无汞催化剂提供了科学基础和参考. 展开更多
关键词 乙炔氢氯化 电子密度 氯化氢活化 稳定机理 金基负载离子液体相催化剂
下载PDF
Stabilizing supported gold catalysts in acetylene hydrochlorination by constructing an acetylene–deficient reaction phase
3
作者 Bolin wang Yuxue Yue +7 位作者 saisai wang Shujuan Shao Zhi Chen Xianhua Fang Xiangxue Pang Zhiyan Pan Jia Zhao Xiaonian Li 《Green Energy & Environment》 SCIE CSCD 2021年第1期9-14,共6页
In the process of acetylene hydrochlorination,the rapid deactivation of supported gold(Au)catalysts by acetylene is still a huge challenge.Here,we provide an innovative strategy for constructing an acetylene–deficien... In the process of acetylene hydrochlorination,the rapid deactivation of supported gold(Au)catalysts by acetylene is still a huge challenge.Here,we provide an innovative strategy for constructing an acetylene–deficient reaction phase on the active site by coating an ionic liquid film on the Au(H2O)/C surface.The reactant ratio of C2H2 to HCl in this acetylene–deficient reaction phase is 1:132,in contrast to the 1:1 M ratio in the gas phase,thus boosting the catalytic stability of Au(H2O)/C catalysts.The kinetic and theoretical analysis showed that the reduction of cationic gold by C2H2 and the generation of carbon deposition can be inhibited in this constructed reaction phase during reaction.The current work not only broadens the scope of supported Au catalysts in acetylene hydrochlorination,but also verifies the perspective of the tunability of stoichiometric balance,which can be used in other catalytic applications. 展开更多
关键词 Supported Au catalysts Acetylene-deficient Reaction phase Acetylene hydrochlorination
下载PDF
Application of endoscopic mucosal advancement in the treatment of chronic anastomotic leakage:A case report
4
作者 Qunmin wang Feixia wang +1 位作者 saisai wang Hanju Hua 《Laparoscopic, Endoscopic and Robotic Surgery》 2022年第3期124-127,共4页
Anastomotic leakage is one of the most serious postoperative complications after colorectal surgery.A fistula or chronic sinus formation is one kind of anastomotic leakage.Most fistulas may heal after conservative tre... Anastomotic leakage is one of the most serious postoperative complications after colorectal surgery.A fistula or chronic sinus formation is one kind of anastomotic leakage.Most fistulas may heal after conservative treatment,but some patients will develop a chronic anastomotic leakage,which definitely requires elective surgery due to the formation of a sinus tract or an internal fistula.This study reports a case of an 88-year-old man with sigmoid colon cancer who developed a chronic anastomotic leakage after colorectal surgery.Endoscopic mucosal advancement combined with titanium clips was success-fully performed to close the fistula.The patient was discharged 12 days after the operation and resumed a normal diet 1 week after discharge.Endoscopic mucosal advancement could be an alternative choice for the treatment of chronic anastomotic leakage and can prevent a secondary surgery;however,good bowel preparation and strict inclusion criteria are required. 展开更多
关键词 ENDOSCOPY Elderly colon cancer Anastomotic leakage Titanium clip
下载PDF
Analysis on the Cy-Pres Doctrine in the Public Benefit Trust
5
作者 saisai wang 《International Journal of Technology Management》 2013年第6期108-110,共3页
关键词 信托 福利 公益事业 公共利益 合理利用 发展趋势 中国 适用性
下载PDF
Effects of theophylline/chitosan/β-cyclodextrin microspheres for oral drug delivery on an asthmatic rat model
6
作者 saisai wang Haijing Zhang +5 位作者 Xiaoming Cui Liping Zhao Mingxia Jiang Zhilu Xu Dongzhen Mu Weifen Zhang 《TMR Modern Herbal Medicine》 2020年第2期66-76,共11页
Objective:This study aimed to investigate the effects of TH/CTS/β-CD microspheres by oral administration on ovalbumin allergic asthma of a rat model.Methods:Spray drying method was applied for preparing the TH/CTS/β... Objective:This study aimed to investigate the effects of TH/CTS/β-CD microspheres by oral administration on ovalbumin allergic asthma of a rat model.Methods:Spray drying method was applied for preparing the TH/CTS/β-CD microspheres,which were used in treatment of asthmatic rats.At a predetermined time,the levels of eosinophil(Eos),protein,lactate dehydrogenase(LDH),aspartate transaminase(AST),glutamic pyruvic transaminase(GPT),and creatinine(Cr)were ascertained by automatic hematology and biochemical analyzers.Lung tissue histology was performed by hematoxylin-eosin staining.Results:No significant differences were found about the contents of Eos in the blood,and the contents of Eos,protein and LDH in the bronchoalveolar lavage fluid between the microsphere-treated and dexamethasone-treated groups,but the levels were lower in both treated groups than in the model group.In the microsphere-treated group,the levels of Cr,AST,and GPT in the serum of rats showed no significant differences compared with the normal group.Based on lung histopathological findings,the microspheres attenuated inflammatory cell infiltration and mucus hypersecretion compared with the model group.Conclusion:This study demonstrated that TH/CTS/β-CD microspheres exerted an anti-inflammatory effect and could serve as a novel promising drug delivery system for asthma treatment. 展开更多
关键词 CHITOSAN THEOPHYLLINE Asthma MICROSPHERES PHARMACODYNAMICS
下载PDF
基于Mg/MgO阈值转变忆阻器的柔性生物可降解人工伤害感受器
7
作者 曹亚雄 王赛赛 +8 位作者 王瑞 辛昱含 彭雅倩 孙静 杨眉 马晓华 吕玲 王宏 郝跃 《Science China Materials》 SCIE EI CAS CSCD 2023年第4期1569-1577,共9页
由于忆阻器能简化人工伤害系统,其在实现人工伤害感受器中引起越来越多的关注.然而,开发具有生物相容性和可降解的人工伤害感受器仍面临挑战.本文提出基于W/MgO/Mg/W结构的生物相容性、可降解的人工伤害感受器.该器件在弯曲条件下具有... 由于忆阻器能简化人工伤害系统,其在实现人工伤害感受器中引起越来越多的关注.然而,开发具有生物相容性和可降解的人工伤害感受器仍面临挑战.本文提出基于W/MgO/Mg/W结构的生物相容性、可降解的人工伤害感受器.该器件在弯曲条件下具有稳定单向阈值转变特性,并模拟了阈值、弛豫、不适应、超敏和超痛的伤害感受行为.器件在可降解衬底上的整体可在去离子水中完全溶解,模仿了皮肤坏死分解过程.本工作为开发生物相容性和可降解的人工伤害感受器提供了一条新途径,有望应用于植入式和可穿戴式电子、安全生物集成系统. 展开更多
关键词 忆阻器 生物可降解 植入式 集成系统 生物相容性 伤害感受器 去离子水 阈值
原文传递
猪esr基因反转录转座子插入多态性及其与大白猪生产性能的关联性分析 被引量:4
8
作者 迟诚林 安亚龙 +6 位作者 李凯媛 顾浩 王赛赛 陈才 高波 宋成义 王宵燕 《生物工程学报》 CAS CSCD 北大核心 2021年第8期2794-2802,共9页
雌激素受体(Estrogen receptor,esr)介导雌激素影响相关基因表达,从而调控哺乳动物的生长和繁殖机能。为了探讨esr基因的反转录转座子多态性对猪生长性能的影响,文中应用比较基因组学和生物信息学方法,预测猪esr基因的反转录转座子插入... 雌激素受体(Estrogen receptor,esr)介导雌激素影响相关基因表达,从而调控哺乳动物的生长和繁殖机能。为了探讨esr基因的反转录转座子多态性对猪生长性能的影响,文中应用比较基因组学和生物信息学方法,预测猪esr基因的反转录转座子插入位点,采用PCR方法验证不同品种猪中插入多态性,并将该基因型与大白猪性能进行关联分析。结果显示,esr1和esr2基因验证后得到4个反转录转座子多态性位点,分别是位于esr1基因内含子2的esr1-SINE-RIP1、位于内含子5的esr1-LINE-RIP2和esr1-SINE-RIP3,以及位于esr2基因内含子1的esr2-LINE-RIP。其中esr1-SINE-RIP1的287 bp SINE插入对大白猪的活体背膘厚和100 kg体重背膘厚有显著影响(P<0.05),纯合有插入(SINE^(+/+))的活体背膘厚和100kg体重背膘厚显著高于杂合有插入(SINE^(+/-))和无插入(SINE^(-/-))型。这表明esr1-SINE-RIP1位点可作为分子标记辅助选育大白猪的背膘厚性状。 展开更多
关键词 雌激素受体 反转录转座子 反转录转座子插入多态 关联分析
原文传递
Orderly defective superstructure for enhanced pseudocapacitive storage in titanium niobium oxide 被引量:4
9
作者 Le Yang Jinfeng Zeng +6 位作者 Lei Zhou Ruiwen Shao Wellars Utetiwabo Muhammad Khurram Tufail saisai wang Wen Yang Jiatao Zhang 《Nano Research》 SCIE EI CSCD 2022年第2期1570-1578,共9页
Artificial defect engineering in transition metal oxides is of important terms for numerous applications.In the present work,we proposed an in-situ gas reduction strategy to introduce ordered defects into titanium nio... Artificial defect engineering in transition metal oxides is of important terms for numerous applications.In the present work,we proposed an in-situ gas reduction strategy to introduce ordered defects into titanium niobium oxide embedding on vapor grew carbon fibers(Ti_(2)Nb_(10)O_(29-x)@VGCFs).High-resolution transmission electron microscopy(HRTEM)and fast Fourier transform(FFT)simulation indicate that the ordered oxygen defects locate at interval layers,which leads to a new superstructure in Ti_(2)Nb_(10)O_(29).The ordered defects could provide extra active sites for lithium-ion storage and modulate ionic migration,resulting an enhanced pseudocapacitive performance.In addition,the excellent structural stability of the superstructure was proved by in-situ HRTEM under a harsh electrochemical process.Our work provides a directly observation of orderly defective superstructure in transition metal oxide,and its functionality on electrochemistry was revealed. 展开更多
关键词 Ti_(2)Nb_(10)O_(29) in-situ gas reduction ordered defect lithium-ion hybrid capacitor PSEUDOCAPACITANCE
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部