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Tuning the cross-linked structure of basic poly(ionic liquid)to develop an efficient catalyst for the conversion of vinyl carbonate to dimethyl carbonate

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Chinese Journal of Chemical Engineering 2024年第8期72卷 106-116页

作者： Zhaoyang Qi Shiquan Zhong huiyun su Changshen Ye Limei Ren Ting Qiu Jie Chen College of Chemical Engineering Fuzhou UniversityFuzhou 350108China Department of Chemical Engineering Shijiazhuang UniversityShijiazhuang 050035China Qingyuan Innovation Laboratory Quanzhou 362801China Fuzhou University International Joint Laboratory of Thermochemical Conversion of Biomass Fuzhou UniversityFuzhou 350108China

Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other *** current primary industrial process employs a conventional sodium methoxide basic catalyst to produce DMC through the transesterification reaction between vinyl carbonate and ***,the utilization of this catalyst presents several challenges during the process,including equipment corrosion,the generation of solid waste,susceptibility to deactivation,and complexities in separation and *** address these limitations,a series of alkaline poly(ionic liquid)s,i.e.[DVBPIL][PHO],[DVCPIL][PHO],and[TBVPIL][PHO],with different crosslinking degrees and structures,were synthesized through the construction of cross-linked polymeric monomers and *** poly(ionic liquid)s exhibit cross-linked structures and controllable cationic and anionic *** was conducted to investigate the effect of the cross-linking degree and structure on the catalytic performance of transesterification in synthesizing *** was discovered that the appropriate cross-linking degree and structure of the[DVCPIL][PHO]catalyst resulted in a DMC yield of up to 80.6%.Furthermore,this catalyst material exhibited good stability,maintaining its catalytic activity after repeated use five times without significant *** results of this study demonstrate the potential for using alkaline poly(ionic liquid)s as a highly efficient and sustainable alternative to traditional catalysts for the transesterification synthesis of DMC.

关键词： Poly(ionic liquid) Cross-linking degree Dimethyl carbonate production Transesterification reaction Mechanism

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Tuning the cross-linked structure of basic poly(ionic liquid) to develop an efficient catalyst for the conversion of vinyl carbonate to dimethyl carbonate

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Chinese Journal of Chemical Engineering 2024年第08期 106-116页

作者： Zhaoyang Qi Shiquan Zhong huiyun su Changshen Ye Limei Ren Ting Qiu Jie Chen College of Chemical Engineering Fuzhou University Qingyuan Innovation Laboratory Department of Chemical Engineering Shijiazhuang University Fuzhou University International Joint Laboratory of Thermochemical Conversion of Biomass Fuzhou University

Dimethyl carbonate(DMC) is a crucial chemical raw material widely used in organic synthesis, lithiumion battery electrolytes, and various other fields. The current primary industrial process employs a conventional sodium methoxide basic catalyst to produce DMC through the transesterification reaction between vinyl carbonate and methanol. However, the utilization of this catalyst presents several challenges during the process, including equipment corrosion, the generation of solid waste, susceptibility to deactivation, and complexities in separation and recovery. To address these limitations, a series of alkaline poly(ionic liquid)s, i.e. [DVBPIL][PHO], [DVCPIL][PHO], and [TBVPIL][PHO], with different crosslinking degrees and structures, were synthesized through the construction of cross-linked polymeric monomers and functionalization. These poly(ionic liquid)s exhibit cross-linked structures and controllable cationic and anionic characteristics. Research was conducted to investigate the effect of the cross-linking degree and structure on the catalytic performance of transesterification in synthesizing DMC. It was discovered that the appropriate cross-linking degree and structure of the [DVCPIL][PHO] catalyst resulted in a DMC yield of up to 80.6%. Furthermore, this catalyst material exhibited good stability,maintaining its catalytic activity after repeated use five times without significant changes. The results of this study demonstrate the potential for using alkaline poly(ionic liquid)s as a highly efficient and sustainable alternative to traditional catalysts for the transesterification synthesis of DMC.

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海口市疏水工程的水力过渡过程及运行控制研究

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水利科学与寒区工程 2024年第1期7卷 27-31页

作者：苏惠云中水珠江规划勘测设计有限公司广东广州510610

针对海口市疏水工程中存在疏浚效率不高等问题,提出海口市疏水工程的运行控制方案,解决了流量增减和流量对水力过渡的影响问题。运行控制三个阶段的累计充水量分别为368.28万m 3、27.00万m^(3)、11.70万m^(3),累计充水时间分别为204.60 ... 详细信息

针对海口市疏水工程中存在疏浚效率不高等问题,提出海口市疏水工程的运行控制方案,解决了流量增减和流量对水力过渡的影响问题。运行控制三个阶段的累计充水量分别为368.28万m 3、27.00万m^(3)、11.70万m^(3),累计充水时间分别为204.60 h、14.30 h、33.00 h。阶段一的累计放水量为368.28万m^(3),累计放水时间为204.26 h,伴随着充水时间的增加,水位开始逐渐变化,并达到疏水的要求。另外,第一阶段任意时刻管道的流速均低于0.6 m/s,达到实际要求。研究结果表明,运行控制方案不仅可以分析水力过渡过程的影响因素,还能够准确地评估渠道和管道运行安全,研究结果可模拟疏水工程的水力过渡工程和运行控制。

关键词：海口市疏水工程水力过渡过程运行控制

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The behaviors of gas-liquid two-phase flow under gas kick during horizontal drilling with oil-based muds

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Petroleum 2024年第1期10卷 49-67页

作者： Yu su huiyun Ma Jianhua Guo Xinyu Shen Zhaoliang Yang Jie Wu Engineering Technology Research Institute PetroChina Southwest Oil & Gas Field Company

Natural gas is easily soluble in oil-based muds(OBM), leading to complex flow behavior in wellbores,especially in horizontal wells. In this study, a new transient flow model considering wellbore-formation coupling and gas solubility on flow behavior is developed to simulate gas kicks during horizontal drilling with OBM. Furthermore, the effect of gas solubility on parameters such as bottom-hole pressure(BHP),gas void fraction and mixture velocity in the flow behavior is analyzed. Finally, several critical factors affecting flow behavior are investigated and compared to gas kicks in water-based muds(WBM) where the effect of solubility is neglected. The results show that the invading gas exists as dissolved gas in the OBM and as free gas in the WBM. Before the gas escapes from the OBM, the pit gain is zero and there is barely any change in the BHP, annulus return flow rate and mixture velocity, which means that detecting gas kicks through these warning signs can be challenging until they get very close to the surface and develop rapidly. However, in WBM drilling, these parameters change quickly with the increasing gas kick time. Additionally, for both cases, the longer the horizontal length and the greater reservoir permeability,the greater the decrease in BHP, and the shorter the time for gas to migrate from the bottom-hole to the wellhead. A larger flow rate contributes to a greater initial BHP and a lesser BHP reduction. This research is of value in characterizing gas kick behavior and identifying novel ways for early gas kick detection during horizontal drilling with OBM.

关键词： Flow behavior Gas solubility Gas kick Horizontal drilling Oil-based muds Water-based muds

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基于灰色模糊理论的小型水利工程临时工程费测算

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水利技术监督 2023年第12期 175-178页

作者：苏惠云中水珠江规划勘测设计有限公司广东广州510610

为保障小型水利工程的正常施工,在充分考虑小型水利工程特点的基础上,采用灰色模糊理论建立小型水利工程临时工程费测算模型,通过实证研究。结果表明采用该模型测算出的临时工程费与实际发生的临时工程费误差小于5%,结果较为接近。临时... 详细信息

为保障小型水利工程的正常施工,在充分考虑小型水利工程特点的基础上,采用灰色模糊理论建立小型水利工程临时工程费测算模型,通过实证研究。结果表明采用该模型测算出的临时工程费与实际发生的临时工程费误差小于5%,结果较为接近。临时费用测算方法准确,可在项目成本估算中进行应用。研究结果为小型水利工程的临时工程费测算提供借鉴。

关键词：灰色模糊理论小型水利工程临时工程费

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有源约束网络的导纳矩阵分析

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天津大学学报 1992年第1期25卷 45-52页

作者：王慧云苏文钧天津大学电子工程系

给出了含有4种类型受控源、运算放大器及跨导运算放大器(OTA)的n端约束网络节点导纳矩阵(或不定导纳矩阵)的构成规则;利用这些规则,可以通过对无约束网络的不定导纳矩阵进行初等的行、列变换得到约束网络的导纳矩阵。

关键词：有源网络约束网络导纳矩阵

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Long-Term Patterns of Meningitis Mortality:A Continual Downward Trend and a Vulnerable Infant Population—China,1987–2021

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China CDC weekly 2023年第34期5卷 745-750页

作者： Yu Wu huiyun Fan Binbin su Chao Guo Luzhao Feng Department of Population Health and Aging Science School of Population Medicine and Public HealthChinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina APEC Health Science Academy(HeSAY) Peking UniversityBeijingChina Institute of Population Research Peking UniversityBeijingChina Department of Infectious Diseases School of Population Medicine and Public HealthChinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina.

summary What is already known about this topic?Meningitis,a life-threatening disease,presents a significant public health *** rate of progress in burden reduction notably lags behind other diseases that can be prevented through *** is added by this report?This research explored the changes in the mortality rate of meningitis in China over a span of 35 *** study further identified the effects of age,period,and cohort on the mortality trends.

关键词： mortality diseases vaccination

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老年非典型肺栓塞误诊为肺炎原因分析

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临床误诊误治 2024年第5期37卷 6-9页

作者：田慧芸苏卫华屈晓娜临汾市人民医院呼吸与危重症医学科山西临汾041000

目的探讨老年非典型肺栓塞的临床特点、误诊原因及防范措施。方法回顾性分析2018年1月—2023年1月收治的曾误诊为肺炎的老年非典型肺栓塞10例的临床资料。结果10例临床主要表现为胸痛、气促、发热和呼吸困难等症状,其中3例肺部可闻及干... 详细信息

目的探讨老年非典型肺栓塞的临床特点、误诊原因及防范措施。方法回顾性分析2018年1月—2023年1月收治的曾误诊为肺炎的老年非典型肺栓塞10例的临床资料。结果10例临床主要表现为胸痛、气促、发热和呼吸困难等症状,其中3例肺部可闻及干啰音,3例肺部听诊可闻及湿啰音。10例胸部X线和(或)CT检查皆提示肺部感染,均被误诊为肺炎。误诊时间3~9 d。10例按误诊疾病给予相应治疗病情反复或持续加重。后均经CT肺动脉造影检查确诊为非典型肺栓塞,给予抗凝、溶栓治疗后均病情好转出院。结论老年非典型肺栓塞患者临床表现无特异性,且大多数患病初期无典型症状,临床和影像学表现同肺炎具有较高重合度,极易误诊。临床上遇及胸闷、呼吸困难且治疗无明显效果的患者,需筛除非典型肺栓塞后,再对患者病情进行诊断,以尽量减少或避免误诊误治。

关键词：肺栓塞非典型老年人误诊肺炎体层摄影术,X线计算机体层摄影术,螺旋计算机血管造影术

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甘肃省成县退耕还林对核桃产业发展的影响

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中国资源综合利用 2015年第6期33卷 61-63页

作者：孟彦斌苏会云何九军王让军黄金泉张少飞陇南师范高等专科学校甘肃省成县农牧局甘肃成县742500

随着国际果品市场的进一步开放及果品产业结构的优化调整,甘肃省成县把握机遇,增加投入,近几年使核桃产业迎来新的发展机遇。退耕还林是国家为了改善一些地方恶劣的生态环境,遏制水土流失,实现人与自然和谐发展而实施的一项生态建设工... 详细信息

随着国际果品市场的进一步开放及果品产业结构的优化调整,甘肃省成县把握机遇,增加投入,近几年使核桃产业迎来新的发展机遇。退耕还林是国家为了改善一些地方恶劣的生态环境,遏制水土流失,实现人与自然和谐发展而实施的一项生态建设工程。分析了退耕还林对成县核桃产业发展的影响,总结了退耕还林给成县带来的利与弊。

关键词：甘肃省成县退耕还林核桃产业发展影响

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Anisotropy of the thermal and laser output properties in Yb,Nd:Sc_(2)SiO_(5) crystal

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Chinese Optics Letters 2021年第4期19卷 62-66页

作者： Yuqing Zhao Qiangguo Wang Lihua Meng Yongping Yao Shande Liu Na Cui Liangbi su Lihe Zheng huiyun Zhang Yuping Zhang College of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao 266590China Collaborative Innovation Center of Light Manipulations and Applications Shandong Normal UniversityJinan 250358China Key Laboratory of Transparent and Opto-functional Inorganic Materials Artificial Crystal Research CenterShanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China School of Physics and Astronomy Yunnan UniversityKunming 650091China

The anisotropy of thermal property in an Yb,Nd∶Sc_(2)SiO_(5) crystal is investigated from the temperature of 293 to 573 K. Based on the systematical study of thermal expansion, thermal diffusivity, and specific heat, the thermal conductivity in Yb,Nd∶Sc_(2)SiO_(5) crystals orientated at(100),(010),(001), and(406) is calculated to be 3.46, 2.60, 3.35, and 3.68 W=/(m·K),respectively. The laser output anisotropy of a continuous-wave(CW) and tunable laser is characterized, accordingly. A maximum output power of 6.09 W is achieved in the Yb,Nd∶Sc_(2)SiO_(5) crystal with(010) direction, corresponding to a slope efficiency of 48.56%. The tuning wavelength range in the Yb,Nd∶Sc_(2)SiO_(5) crystal orientated at(100),(010), and(001) is 68, 67,and 65 nm, separately. The effects of thermal properties on CW laser performance are discussed.

关键词： anisotropy thermal property tunable laser Yb Nd:Sc_(2)SiO_5 crystal

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