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Chinese Journal of Chemistry 2024年第14期42卷 1571-1581页

作者： Yongjie Chen yanwei wang Jun Nong Dan Yuan Yingming Yao Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceDushu Lake CampusSoochow UniversitySuzhouJiangsu215123 China

Eight zwitterionic rare earth metal complexes stabilized by amino-bridged tris(phenolato)ligands bearing quaternary ammonium side-arms were synthesized and *** complexes were used as single-component catalysts for the cycloaddition of CO_(2)and epoxides,and their catalytic activities are obviously higher than those of their binary *** studies revealed that the halide anions(Cl^(–),Br^(–),I^(–))and the metal complexes influenced the catalytic activity,and the lanthanum complex bearing iodide anion showed the highest catalytic activity for this addition reaction.A variety of mono-substituted epoxides were converted to cyclic carbonates in good to excellent yields(55%—99%)with high selectivity(>99%)at 30℃and 1 bar CO_(2),whereas internal epoxides required higher both reaction temperatures(60—120℃)and catalyst loading(2 mol%)for high *** catalyst was recyclable for four times without noticeable loss of catalytic *** on the results of kinetic studies and in℃situ IR reactions,a plausible reaction mechanism was proposed.

关键词： Bifunctional catalyst Carbon dioxide Cyclic carbonate Rare-earth metal Tris(phenolato)ligand Insertion Cycloaddition C1 building blocks

Selective nickel-electrocatalyzed benzylic C-H oxygenation of functionalized alkyl arenes

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Chinese Chemical Letters 2024年第2期35卷 396-401页

作者： Shunyao Tang Siyi wang Dongmei Zhang Xinxing Zhang Guang Yang yanwei wang Youai Qiu State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China College of Chemistry Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education)Renewable Energy Conversion and Storage Center (RECAST)Frontiers Science Center for New Organic MatterNankai UniversityTianjin 300071China

Herein, a site-selective paired electrochemical C–H oxidation of functionalized alkyl arenes promoted by nickel catalyst is disclosed. A Ni(Ⅱ)-dioxygen species formed in situ efficiently enable the oxidation process under mild conditions with a broad substrate scope with excellent functional group compatibilities,such as free carboxylic acid, aldehyde, halogen(including aryl iodide), amide and amino acid. The use of the nickel catalyst in combination with water provides a safe, green and economical method for oxidation of a range of molecules varying in complexity and drug derivatives, demonstrating its potential application in organic synthesis and the pharmaceutical industry. Reaction outcomes and mechanistic studies revealed the key role of the in situ Ni(Ⅱ)-dioxygen species for the subsequent oxidation of C(sp^(3))–H bonds,and short-lived reactive intermediates(aryl radical cation) was rapidly captured by the combination of a bipolar ultramicroelectrode(BUME) with nano-electrospray ionization mass spectrometry.

关键词： Electrochemical C-H oxidation Functionalized alkyl arenes Paired nickel-electrocatalysis H_(2)O oxidation Ketones

Selection of New Energy Development Models in Rural Jilin Province under Different Situations

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Proceedings of Business and Economic Studies 2024年第4期7卷 231-237页

作者： Lijuan Zhang Xuetao Tang Yiwen wang yanwei wang School of Economics and Management Northeast Electric Power UniversityJilin 132011Jilin ProvinceChina Jilin City No.1 Middle School Jilin 132000Jilin ProvinceChina

Jilin Province’s vast rural areas are endowed with abundant new energy resources,which provide a fundamental condition for the development of new energy in rural *** paper will explore the various possibilities of new energy development in rural Jilin under the background of grid infrastructure construction,the deepening of electricity market reform,the modernization of agriculture and rural areas,and the transformation of *** will draw conclusions on the reasonable development models of new energy in rural Jilin under different scenarios,providing a reference for the development of new energy in rural Jilin and rural revitalization.

关键词： Rural revitalization Rural areas New energy

Mutation in a non-force-bearing region of protein L influences force-dependent unfolding behavior

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Chinese Physics B 2024年第7期33卷 624-629页

作者：蒋环杰王艳伟陈家媛胡丹潘海郭子龙陈虎 Department of Physics Wenzhou UniversityWenzhou 325035China Center of Biomedical Physics Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhou 325000China Research Institute for Biomimetics and Soft Matter Fujian Provincial Key Laboratory for Soft Functional Materials ResearchDepartment of PhysicsXiamen UniversityXiamen 361005China

Single-molecule magnetic tweezers(MTs) have revealed multiple transition barriers along the unfolding pathway of several two-state proteins, such as GB1 and Csp. In this study, we utilized MTs to measure the force-dependent folding and unfolding rates of both protein L(PLWT) and its Y47W mutant(PLY47W) where the mutation point is not at the force-bearing β-strands. The measurements were conducted within a force range of 3–120 pN. Notably, the unfolding rates of both PLWT and PWY47W exhibit distinct force sensitivities below 50 pN and above 60 pN, implying a two-barrier free energy landscape. Both PLWT and PLY47W share the same force-dependent folding rate and the same transition barriers,but the unfolding rate of PLY47W is faster than that of PLWT. Our finding demonstrates that the residue outside of the force-bearing region will also affect the force-induced unfolding dynamics.

关键词： protein folding magnetic tweezers protein L

Association of a complete breast cancer pathologic response with axillary lymph node metastasis via neoadjuvant chemotherapy:Results from the CSBrS-012 study

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Chinese Medical Journal 2024年第11期137卷 1369-1371页

作者： Le Ma Pin Gao Zhenzhen Liu Dechuang Jiao Rui Ling Jingjing Xiao Yi Zhao Yitong wang Hongjian Yang Yunjiang Liu Ke Liu Jianguo Zhang Guangyan Li Dahua Mao Yinglei Deng Jianjun He Maimaitiaili Amina Zhigang Yu wang Fei Yinhua Liu Peifen Fu Minya Yao Jiandong wang Li Zhu Hongchuan Jiang Zuowei Zhao Xingsong Tian Zhongwei Cao Xinyu Ma Kejin Wu Shaomei Fu Ailin Song yanwei wang Jin Feng Zhimin Fan Department of Breast Surgery General Surgery CenterThe First Hospital of Jilin UniversityChangchunJilin 130021China Department of Breast Disease Henan Breast Cancer CenterAffiliated Cancer Hospital of Zhengzhou University&Henan Cancer HospitalZhengzhouHenan 450008China Department of Thyroid Breast and Vascular SurgeryXijing HospitalFourth Military Medical UniversityXi’anShaanxi 710032China Surgical Oncology Department Shengjing Hospital of China Medical UniversityShenyangLiaoning 110022China Department of Breast Surgery The Cancer Hospital of the University of Chinese Academy of Sciences(Zhejiang Cancer Hospital)Institute of Basic Medicine and Cancer(IBMC)Chinese Academy of SciencesHangzhouZhejiang 310022China Department of Surgery The Fourth Hospital of Hebei Medical UniversityShijiazhuangHebei 052360China Fourth Department of Breast Surgery Jilin Cancer HospitalChangchunJilin 130012China Department of Breast Surgery The Second Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjiang 150086China Department of Breast Surgery Affiliated Wudang Hospital of Guizhou Medical UniversityGuiyangGuizhou 550009China Department of Breast Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’anShaanxi 710061China Department of Breast Surgery The Second HospitalCheeloo College of MedicineShandong UniversityJinanShandong 250033China Breast Disease Center Peking University First HospitalBeijing 100034China Department of Breast Surgery The First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhouZhejiang 310003China Department of General Surgery The First Medical CenterChinese PLA General HospitalBeijing 100852China Department of Breast Surgery Beijing Chaoyang HospitalCapital Medical UniversityBeijing 100020China Department of Breast Surgery The Second Affiliated Hospital of Dalian Medical UniversityDalianLiaoning 116023China Department of Breast and Thyroid Surgery Shandong Provincial Hospital Affiliated to Shandong UniversityJinan

To the Editor:In the last decade,neoadjuvant chemotherapy(NAC)has become a well-accepted treatment option for breast cancer,although few detailed description of NAC in China has yet been reported.[1]A previous study found that among patients with clinically node-negative(cN0)breast cancer,97.7%(432/442)with breast pathologic complete response(bpCR)had ypN0(absence of metastases in the axillary lymph nodes);and 71.6%(882/1232)without bpCR achieved ypN0(P<0.001).As for human epidermal growth factor receptor 2(HER2)positive or triple-negative breast cancer(TNBC)that achieved bpCR.

关键词： breast pathologic chemotherapy

TaqMan多重实时定量PCR快速检测3种常见食源性病原菌

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中国食品学报 2024年第5期24卷 373-380页

作者：艾鹏飞王珊高辉明王雁伟庞艳荣张萌河北科技大学食品与生物学院石家庄050018

建立一种可同时快速检测大肠杆菌O157:H7、单增李斯特菌和蜡样芽孢杆菌的多重实时定量PCR(qPCR)方法。依据大肠杆菌O157:H7 tir基因、单增李斯特菌mpl基因和蜡样芽孢杆菌entFM基因的保守序列分别设计特异性引物和TaqMan探针,建立多重qPC... 详细信息

建立一种可同时快速检测大肠杆菌O157:H7、单增李斯特菌和蜡样芽孢杆菌的多重实时定量PCR(qPCR)方法。依据大肠杆菌O157:H7 tir基因、单增李斯特菌mpl基因和蜡样芽孢杆菌entFM基因的保守序列分别设计特异性引物和TaqMan探针,建立多重qPCR反应体系,进行灵敏度、特异性和稳定性试验,同步检测人工染菌牛奶样品中的病原菌并与国家标准方法作对比。结果表明,建立的多重qPCR方法灵敏度高,最低检出限为12 CFU/mL;特异性强,只对3种目标菌进行PCR扩增;稳定性好,各重复性试验中Ct值的变异系数<1%;所有受污染样品阳性检出率均为100%,与国家标准方法检测结果一致,且检测周期缩短至6 h。本研究建立的TaqMan多重qPCR方法能同时快速、准确地检测乳品中的大肠杆菌O157:H7、单增李斯特菌和蜡样芽孢杆菌,为食品安全提供技术支撑。

关键词： TaqMan探针多重实时定量PCR 大肠杆菌O157:H7 单增李斯特菌蜡样芽孢杆菌

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供给主体视角下红树林碳汇项目全生命周期风险测度与评价研究——以湛江红树林造林项目为例

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海洋通报 2024年第2期43卷 248-264页

作者：贺义雄王燕炜谢素美浙江海洋大学经济与管理学院浙江舟山316022 南方海洋科学与工程广东省实验室(珠海) 广东珠海519000 自然资源部南海发展研究院广东广州510310

发展海洋碳汇对于建设人与自然和谐共生的美好世界具有重要意义,红树林作为海洋碳汇的重要来源,拥有强大的固碳和储碳能力,具有较高的生态价值和经济价值,因此,加快开发红树林碳汇是应对气候变化的重要战略选择。本文基于三角模糊数和... 详细信息

发展海洋碳汇对于建设人与自然和谐共生的美好世界具有重要意义,红树林作为海洋碳汇的重要来源,拥有强大的固碳和储碳能力,具有较高的生态价值和经济价值,因此,加快开发红树林碳汇是应对气候变化的重要战略选择。本文基于三角模糊数和结构方程构建红树林碳汇项目风险测度模型,选取湛江红树林造林项目这一我国的代表性项目,采用净现值方法和肯定当量法对其进行实证对比分析,测度风险因素对项目价值及其投资决策的影响,从而助力红树林碳汇的高质量发展。结果表明:(1)红树林碳汇项目的开发存在一定的风险,各阶段风险按照影响由高到低,依次为核查备案阶段、决策阶段、施工阶段、运营维护阶段和设计阶段,核查备案阶段的技术风险、决策阶段的政策风险、施工阶段的市场风险、运营维护阶段的市场风险和设计阶段的人类行为风险是各阶段中影响较大的风险种类;(2)风险的发生会使红树林碳汇项目的价值降低,相比传统净现值法,肯定当量法更符合红树林碳汇项目的开发和运行情况。

关键词：红树林碳汇项目风险测度与评价供给主体全生命周期

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两性别分枝交互粒子系统以及相应的极限方程

应用概率统计 2024年第4期40卷 543-557页

作者：马儒刚王燕伟赵涵中财财经大学统计与数学学院北京100081

我们通过由泊松随机测度驱动的随机方程构造了一类两性别分枝交互粒子系统,系统中的粒子可以随机地与异性进行交配,其后产生的后代个数也是随机的,后代个数的分布由一个与粒子特征和整个系统有关的母函数决定.我们证明了在适当的条件下... 详细信息

我们通过由泊松随机测度驱动的随机方程构造了一类两性别分枝交互粒子系统,系统中的粒子可以随机地与异性进行交配,其后产生的后代个数也是随机的,后代个数的分布由一个与粒子特征和整个系统有关的母函数决定.我们证明了在适当的条件下,这个分枝交互粒子系统的重整化极限是一个确定的测度值函数,它满足某个特定的非线性常微分方程.最后我们得到了一个非线性常微分方程组来刻画各性别所属的亚种群的特征分布.

关键词：两性别分枝交互粒子系统随机积分方程重整化极限测度值函数

结构性货币政策工具对科技创新型企业融资的影响

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金融发展研究 2024年第7期 48-55页

作者：王延伟高晓改刘鹏中国人民银行山东省分行山东济南250021 中国人民银行济南分行营业管理部山东济南250021

近年来,货币政策工具在发挥总量调节功能的同时,也有力地支持了经济结构调整和转型升级。2013年起,为加强对“三农”、小微等重点领域及薄弱环节的金融信贷支持,中国人民银行创设了常备借贷便利、抵押补充贷款、定向降准等结构性货币政... 详细信息

近年来,货币政策工具在发挥总量调节功能的同时,也有力地支持了经济结构调整和转型升级。2013年起,为加强对“三农”、小微等重点领域及薄弱环节的金融信贷支持,中国人民银行创设了常备借贷便利、抵押补充贷款、定向降准等结构性货币政策工具,向实体经济精准释放流动性,以期达到优化调节经济结构的政策目的。本文从结构性货币政策工具与科技创新型企业融资间的关系出发,尝试对结构性货币政策工具支持科技创新型企业的效果进行评价,认为结构性货币政策工具能够促进科技创新型企业融资,且在不良贷款率较低、地区GDP增长率较高的金融机构中具有更强的政策传导效应,更能促进科技创新型企业贷款增量扩面。在此基础上,提出应从加强结构性货币政策工具支持力度,完善结构性货币政策工具设计,加强货币、财政、产业政策协调配合三个方面改善结构性货币政策工具传导效能。

关键词：结构性货币政策工具科技创新型企业政策传导

复杂地质条件下市政高架桥与盾构区间近接施工影响研究

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工程建设 2024年第8期56卷 61-65,90页

作者：王彦伟山东省交通科学研究院山东济南250014

为研究轨道交通工程与新建市政桥梁近接施工过程中的相互影响关系,文章以某新建市政高架桥与盾构区间近接施工为例,研究施工方案对高架桥及区间的影响效果,并对施工过程中的风险采取一定的措施,利用GTSNX岩土数值模拟软件,建立三维模型... 详细信息

为研究轨道交通工程与新建市政桥梁近接施工过程中的相互影响关系,文章以某新建市政高架桥与盾构区间近接施工为例,研究施工方案对高架桥及区间的影响效果,并对施工过程中的风险采取一定的措施,利用GTSNX岩土数值模拟软件,建立三维模型并模拟相关的施工顺序,对工程关键位置进行变形分析。同时结合类似工程,提出高架桥与其他市政工程近接施工过程中的风险把控重点。研究结果表明:桥梁上部结构施工后,区间竖向变形值与区间结构距桥梁桩基的距离正相关,以期对类似市政近接施工提供一定的参考价值。

关键词：近接施工高架桥盾构区间相互影响