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Combined use of an alkene and a phosphine as a nucleophilic catalyst system for the cyanosilylation of carbonyl compounds

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Chinese Science Bulletin 2010年第25期55卷 2820-2823页

作者： wang xiu fang Fan TIAN ShiKai Department of Chemistry University of Science and Technology of China Hefei 230026 China

The catalytic potential of carbon nucleophiles has seldom been disclosed due to their reactivity toward carbon electrophiles to form stable carbon-carbon bonds,which are too strong to be cleaved for the expected catalytic cycles. We have developed an efficient catalytic cyanosilylation of carbonyl compounds with an in situ generated alkene/phosphine adduct,which is tuned not to couple with a carbonyl compound or an electron-deficient alkene under the reaction conditions when its nucleophilicity is trans-lated into catalytic activity. In the presence of 3 mol% of methyl acrylate and 3 mol% of triphenylphosphine,a broad range of alkyl,alkenyl,and aryl ketones and aldehydes undergo cyanosilylation reaction with trimethylsilyl cyanide at room temperature to yield structurally diversified cyanohydrin silyl ethers in excellent yields. By using methyl acrylate/triphenylphosphine as a highly effective nucleophilic catalyst system for the cyanosilylation of carbonyl compounds,this study demonstrates a new concept for the development of useful organocatalysis utilizing the nucleophilicity of alkene/phosphine adducts generated in situ.

关键词：羰基化合物亲核试剂催化体系烯烃联合使用磷化氢甲基丙烯酸酯三苯基膦

基于VisuShrink小波阈值变换的甲烷检测降噪技术

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化工自动化及仪表 2024年第3期51卷 410-416页

作者：姜建国胡钧凯王秀芳东北石油大学电气信息工程学院

在利用可调谐半导体激光吸收光谱技术探测甲烷气体泄漏时,复杂的环境光干扰会降低浓度检测信号的信噪比使波形失真。为了抑制噪声,增强电信号与浓度值的线性相关度,提出一种以VisuShrink方法改善小波阈值函数的小波阈值去噪算法。该算... 详细信息

在利用可调谐半导体激光吸收光谱技术探测甲烷气体泄漏时,复杂的环境光干扰会降低浓度检测信号的信噪比使波形失真。为了抑制噪声,增强电信号与浓度值的线性相关度,提出一种以VisuShrink方法改善小波阈值函数的小波阈值去噪算法。该算法针对小波阈值去噪算法的软硬度不能平衡信号,存在失真的问题,利用统计方法对阈值进行计算,弱化间断点阈值跳变影响。通过仿真计算对比未加噪声前的信号与滤波后的信号,提出算法的信噪比为28.405 30,优于四阶巴特沃斯滤波器。VisuShrink方法在SNR和NCC参数上性能远优于巴特沃斯滤波器,与软阈值函数相近,在MSE均方误差分析上远小于软阈值精度,与巴特沃斯相近,具有较好的平滑特性。实际搭建检测平台对多个浓度样本采样进行多次采样,采用VisuShrink方法设计的滤波器将系统误差精度从4.14%提升至2.472%,算法可有效用于甲烷检测系统提高光谱数据的平滑性和准确性。

关键词：可调谐半导体激光吸收光谱气体浓度测量波长调制光谱技术小波阈值去噪甲烷泄漏

超声引导下QLB与TAPB在剖宫产术后镇痛中的应用

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海南医学 2024年第1期35卷 84-87页

作者：折甜甜王秀芳孙逸飞西电集团医院麻醉科陕西西安710003 兴平市妇幼保健院麻醉科陕西兴平713100

目的探讨超声引导下腰方肌阻滞(QLB)与腹横肌平面阻滞(TAPB)在剖宫产术后镇痛中的应用效果。方法选择2022年1月至2023年4月在西电集团医院行剖宫产的200例产妇作为研究对象,按照随机数表法将产妇分为观察组和对照组,每组100例。观察组... 详细信息

目的探讨超声引导下腰方肌阻滞(QLB)与腹横肌平面阻滞(TAPB)在剖宫产术后镇痛中的应用效果。方法选择2022年1月至2023年4月在西电集团医院行剖宫产的200例产妇作为研究对象,按照随机数表法将产妇分为观察组和对照组,每组100例。观察组产妇术后采用超声引导下QLB,对照组产妇术后采用超声引导下TAPB。比较两组产妇术后镇痛情况、术后恢复情况、术后4 h、12 h、24 h、48 h的视觉模拟评分法(VAS)评分,并比较两组产妇的不良反应发生率及对镇痛的满意度。结果观察组产妇首次按压静脉自控镇痛(PCIA)时间为(10.39±1.47)h,明显长于对照组的(7.85±1.59)h,术后24 h按压次数、舒芬太尼用量分别为(3.40±0.65)次、(41.83±5.73)μg,明显少于对照组的(5.18±0.49)次、(60.32±7.69)μg,差异均具有统计学意义(P0.05);观察组产妇的不良反应总发生率为4.00%,明显低于对照组的12.00%,观察组产妇对镇痛的总满意率为94.00%,明显高于对照组的83.00%,差异均有统计学意义(P<0.05)。结论超声引导下QLB在剖宫产术后的镇痛效果优于超声引导下TAPB,且更有助于促进产后恢复,并能降低不良反应,临床应用价值高。

关键词：剖宫产超声腰方肌阻滞腹横肌平面阻滞镇痛

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化瘀生新合剂联合雷火灸预防人流术后宫腔粘连的临床观察

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广州中医药大学学报 2024年第5期41卷 1202-1206页

作者：李淑华王秀芳刘玉兰广州中医药大学广东广州1510006 广东省清远市中医院妇科广东清远511599

【目的】观察化瘀生新合剂(由黄芪、当归、党参、川芎、桃仁、益母草、白术、炮姜、炙甘草等9味中药组成)联合雷火灸对促进人工流产术(简称人流术)后子宫内膜修复、预防宫腔粘连的临床疗效。【方法】将60例确诊为早期宫内妊娠并自愿行... 详细信息

【目的】观察化瘀生新合剂(由黄芪、当归、党参、川芎、桃仁、益母草、白术、炮姜、炙甘草等9味中药组成)联合雷火灸对促进人工流产术(简称人流术)后子宫内膜修复、预防宫腔粘连的临床疗效。【方法】将60例确诊为早期宫内妊娠并自愿行人流术的患者随机分为对照组和观察组,每组各30例。对照组给予雌激素疗法治疗,即于人流术后当天开始予以口服补佳乐治疗,观察组在对照组的基础上给予化瘀生新合剂联合雷火灸(取穴:中极、神阙、关元、双侧子宫、双侧归来)治疗。观察2组患者的子宫恢复情况、子宫动脉血流情况、子宫结合带连续性情况以及不良反应发生情况。【结果】(1)子宫恢复情况:与对照组相比,观察组的阴道流血时间和月经复潮时间明显缩短,子宫内膜厚度明显增厚,差异均有统计学意义(P0.05)。(3)子宫结合带连续性情况:与对照组相比,观察组的子宫结合带中断例数较对照组少,连续性情况明显优于对照组,差异有统计学意义(P<0.05)。(4)不良反应发生情况:治疗期间,2组患者均无出现严重的不良反应,具有较高的安全性。【结论】人流术后在雌激素疗法基础上加用化瘀生新合剂联合雷火灸治疗,能更有效促进子宫内膜修复,从而更好地预防宫腔粘连。

关键词：雌激素疗法补佳乐化瘀生新合剂雷火灸人工流产术后子宫内膜宫腔粘连

Synthesis, DNA-binding, and Photocleavage of 2,3-Di-2-pyridylquinoxaline-silver(Ⅰ) Complex

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Chemical Research in Chinese Universities 2008年第1期24卷 15-19页

作者： wang xiu-li fang Jia-ni BI Yan-feng LIN Hong-yan LIU Guo-cheng Faculty of Chemistry and Chemical Engineering Liaoning Key Laboratry of Applied Chemistry Bohai University Jinzhou 121000 P. R. China

A new dinuclear complex, [Ag（L）（CH3CN）]2（ClO4）2·2H2O（L=2,3-di-2-pyridylquinoxaline）, was prepared and characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction analyses. The interaction of the complex with calf thymus DNA（CT-DNA） was investigated by absorption, fluorescence spectroscopies, and viscosity measurement. The results suggested that the complex was bound to DNA via an intercalative mode. The intrinsic binding constant value Kb was found to be approximately 1.48×10^3 L·mol^-1. Moreover, the Ag（I） complex could cleave the plasmid pUC19 DNA from the supercoiled Form Ⅰto the nicked FormⅡ under irradiation at 365 nm.

关键词： DNA Ag-Polypyridyl complex Interaction Fluorescence Cleavage

双向接头型伸缩管连接喉罩在无痛支气管镜检查治疗中的应用

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海南医学 2024年第2期35卷 220-224页

作者：折甜甜王秀芳孙逸飞刘文雄西电集团医院麻醉科陕西西安710003 兴平市妇幼保健院麻醉科陕西兴平713100

目的探究双向接头型伸缩管连接喉罩在无痛支气管镜检查治疗中的应用价值。方法前瞻性选取2022年1月至2023年5月期间在西电集团医院行纤维支气管镜检查与治疗的80例患者作为研究对象。采用随机数表法将患者分为观察组和对照组各40例,观... 详细信息

目的探究双向接头型伸缩管连接喉罩在无痛支气管镜检查治疗中的应用价值。方法前瞻性选取2022年1月至2023年5月期间在西电集团医院行纤维支气管镜检查与治疗的80例患者作为研究对象。采用随机数表法将患者分为观察组和对照组各40例,观察组患者采用双向接头型伸缩管连接喉罩麻醉方式,对照组患者采用口腔气道表面喷洒丁卡因麻醉方式。比较两组患者在麻醉前(T0)、进镜前(T1)、支气管镜通过声门部(T2)、检查中(T3)和检查结束(T4)这5个时间点的血压(BP)、血氧饱和度(SpO2)、心率(HR)、血氧分压(PO2)等指标;比较两组患者的镜检时间和检查期间有无体动、中断操作、呛咳等情况以及术后咽喉部疼痛、不能发声、声嘶等不良反应;术后问卷调查患者对操作的满意度以及对内镜医师的麻醉满意度。结果两组患者T1时BP较T0时明显下降,差异有统计学意义(P0.05);对照组患者的SpO2在T2明显低于T0、T1、T3、T4,且明显低于观察组,对照组患者的HR、BP、MAP在T2明显高于T0、T1、T3、T4,且各指标明显高于观察组,差异均有统计学意义(P<0.05);观察组患者的术中体动、术中呛咳、中断操作、术后咽喉部疼痛、声嘶、不能发声情况发生率分别为7.50%、7.50%、5.00%、5.00%、2.50%、2.50%,明显低于对照组的45.00%、57.50%、25.00%、25.00%、15.00%、17.50%,差异均有统计学意义(P<0.05);观察组患者的镜检时间为(9.53±2.31) min,明显短于对照组的(18.65±3.51) min,患者对操作和医师的满意度得分分别为(96.52±2.34)分、(95.48±2.37)分,明显高于对照组的(54.60±1.38)分、(60.64±1.42)分,差异均有统计学意义(P<0.05)。结论双向接头型伸缩管连接喉罩在无痛支气管镜检查治疗中能有效解决检查过程中的通气问题,有助于稳定血流动力学,减少呼吸抑制,减少患者痛苦记忆,提升患者对操作和医师的满意度。

关键词：支气管镜检查喉罩双向接头型麻醉伸缩管血流动力学满意度

DGK5-mediated phosphatidic acid homeostasis interplays with reactive oxygen species in plant immune signaling

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Journal of Integrative Plant Biology 2024年第7期66卷 1263-1265页

作者： Dian wang Minhang Yuan Yamei Zhuang xiu-fang Xin Guang Qi Crop Research Institute Shandong Academy of Agricultural Sciences/National Engineering Research Center of Wheat and Maize/Shandong Technology Innovation Center of WheatJinan 252100China College of Agronomy Qingdao Agricultural UniversityQingdao 266109China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China

Plants have evolved a complex innate immune system that deploys two interconnected receptor layers to detect the invasion of various *** surface-resident pattern recognition receptors(PRRs)perceive pathogen-or microbeassociated molecular patterns(PAMPs/MAMPs),initiating a basal defense response called pattern-triggered immunity(PTI)(Zhou and Zhang,2020).

关键词： pattern homeostasis immunity

Oxidation behavior of 4774DD1 Ni-based single-crystal superalloy at 980℃ in air

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China Foundry 2024年第2期21卷 116-124页

作者： Yu fang Ya-zhou Li Qiang Yang Qun-gong He xiu-fang Gong Qian Duan Hai-yang Song Fu wang Qiong-yuan Zhang Hong Zeng State Key Laboratory of Long-Life High Temperature Materials Dongfang Turbine Co.Ltd.Deyang 618000SichuanChina State Key Laboratory for Manufacturing System Engineering School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China

The oxidation behavior of a novel Ni-based single-crystal 4774DD1 superalloy for industrial gas turbine applications was investigated by the isothermal oxidation at 980℃ and discontinuous oxidation weight gain *** phase constitution and morphology of surface oxides and the characteristics of the crosssection oxide film were analyzed by XRD,SEM and *** show that the oxidation kinetics of the 4774DD1 superalloy follows the cubic law,indicating its weak oxidation resistance at this *** the oxidation time increases,the composition of the oxide film evolves as following:One layer consisting of a bottom Al_(2)O_(3)sublayer and an upper(Al_(2)O_(3)+NiO)mixture sublayer after oxidized for 25 ***,two layers composed of an outermost small NiO discontinuous grain layer and an internal layer for 75 *** internal layer is consisted of the bottom Al_(2)O_(3)sublayer,an intermediate narrow CrTaO_(4)sublayer,and an upper(Al_(2)O_(3)+NiO)mixture *** two layers comprising an outermost relative continuous NiO layer with large grain size and an internal layer as the oxidation time increases to 125 *** internal layer is composed of the upper(Al_(2)O_(3)+NiO)mixture sublayer,an intermediate continuous(CrTaO_(4)+NiWO_(4))mixture sublayer,and a bottom Al_(2)O_(3)***,three layers consisting of an outermost(NiAl2O_(4)+NiCr2O_(4))mixture layer,an intermediate(CrTaO_(4)+NiWO_(4))mixture layer,and a bottom Al_(2)O_(3)layer for 200 h.

关键词： nickel-base single crystal superalloy oxidation kinetics oxide film microstructure mechanism

Sequential enantioselective Ugi-4CR/post-Ugi transformation strategy:a precise construction of structurally diverse azaspiro polycyclic scaffolds

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Science China Chemistry 2024年第2期67卷 576-586页

作者： Xiao-Bao Wu Jun-xiu Shi Yi-Ming Ou Hua-Jie Jiang Yi-Jun fang Qi-Ming wang Quan Gao Jie Yu Department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic *** diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis