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Mass Spectrometric Studies on Metal-hexafluorobenzene Anionic Complexes(M=Ag, Au, Pd, Pt, Pb and Bi)

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Chemical Research in Chinese Universities 2009年第2期25卷 228-233页

作者： SUN Zhang SUN Shu-tao LIU Hong-tao zhu qi-he GAO Zhen TANG Zi-chao Beijing National Laboratory for Molecular Sciences（BNLMS） State Key Laboratory of Molecular Reaction Dynamics Center of Molecular Science Institute of Chemistry Chinese Academy of Sciences Beo＇ing 100080 P. R. China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 P R. China

The anionic products from the reactions between metal（M=Ag, Au, Pd, Pt, Pb and Bi） vapour produced by laser ablation and hexafluorobenzene seeded in carrier gas（Ar） were studied by means of a homemade reflectron time-of-flight mass spectrometry（RTOF-MS）. Experimental results show that the dominant products were [MmC6F6]^- complexes for the reactions ofAg, Au, Pd and Pt with C6F6, while the dominant products were [MmC6F5]^- complexes for the reactions of Pb and Bi with C6F6. The formation mechanisms of the products, including the adsorption of metal cluster anions on hexafluorobenzene and the C--F cleavage induced by metal cluster anions, were discussed.

关键词： Time-of-flight mass spectrometer Metal cluster Anionic complex Reaction mechanism

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铬/磷二元团簇的形成和光解

高等学校化学学报 2001年第4期22卷 622-625页

作者：韩春英邢小鹏高振朱起鹤中国科学院化学研究所分子反应动力学国家重点实验室北京100080

用 53 2 nm的 Nd∶ YAG激光直接溅射铬 /磷粉末混合物样品产生铬 /磷团簇 ,并用串级飞行时间质谱仪研究了二元团簇的组份分布及紫外激光光解规律 .实验表明 ,铬 /磷极易形成富磷的二元团簇离子 ,Cr P+ m团簇离子系列表现出明显的奇偶振... 详细信息

用 53 2 nm的 Nd∶ YAG激光直接溅射铬 /磷粉末混合物样品产生铬 /磷团簇 ,并用串级飞行时间质谱仪研究了二元团簇的组份分布及紫外激光光解规律 .实验表明 ,铬 /磷极易形成富磷的二元团簇离子 ,Cr P+ m团簇离子系列表现出明显的奇偶振荡效应 ,且 Cr P+ 4,Crn P+ 8(n=1～ 4 ) ,Cr4 P+ 9,Cr5P+ 11,Cr6P+ 12 和 Cr8P+ 14 等为质谱中丰度较大的离子 ,不随样品组成的变化而变化 ,光解时主要以失去中性 P2 和 P4 的方式进行解离 ,尝试对其电子结构进行推测 .并与铬

关键词：铬磷激光溅射激光光解形成机理二元团簇

Mn/Se,MnO_2/Se和Mn/SeO_2体系形成的团簇离子的质谱研究

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高等学校化学学报 2000年第5期21卷 743-746页

作者：陈云清邢小鹏刘鹏曾嵘高振朱起鹤分子反应动力学国家重点实验室分子科学中心中国科学院化学研究所北京100080

用飞行时间质谱法研究了激光直接溅射Ｍｎ／Ｓｅ混合样品产生的二元团簇、团簇的光解行为及溅射ＭｎＯ２／Ｓｅ和Ｍｎ／ＳｅＯ２样品产生的团簇正负离子．在Ｍｎ－Ｓｅ二元团簇中，（Ｍｕｓｅ）ｎ＋是正离子的主要组分，［（Ｍｕｓ... 详细信息

用飞行时间质谱法研究了激光直接溅射Ｍｎ／Ｓｅ混合样品产生的二元团簇、团簇的光解行为及溅射ＭｎＯ２／Ｓｅ和Ｍｎ／ＳｅＯ２样品产生的团簇正负离子．在Ｍｎ－Ｓｅ二元团簇中，（Ｍｕｓｅ）ｎ＋是正离子的主要组分，［（Ｍｕｓｅ）ｎＳｅ］－是负离子的主要组分．当ｎ<５时，（Ｍｕｓｅ）ｎ＋的紫外光解有多种通道；ｎ≥５时光解以剥落ＭｕＳｅ方式进行．激光直接溅射ＭｎＯ２／Ｓｅ，Ｍｎ／ＳｅＯ２两种体系产生的正负离子极为相似，符合团簇的气相聚合生长机理．正离子中（Ｍｎｏ）ｎ＋是主要组分，负离子中Ｓｅｎ－，（ＳｅＯ）－和（ＳｅｎＯ３）－是主要组分．

关键词：紫外光解锰二元团簇离子氧族元素质谱

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钪-硫团簇的形成和光解

化学学报 1998年第7期56卷 675-681页

作者：王文静胡东波刘鹏高振孔繁敖朱起鹤中国科学院化学研究所分子反应动力学国家重点实验室北京100080

报道了用激光直接溅射法产生钪硫团簇,并用串级飞行时间质谱仪研究了所产生的团簇离子的分布及紫外激光光解规律.钪硫二元团簇正负离子都是由周边硫原子包围团簇骨架而构成的,骨架是由包含着不同数目的Sc_2C_3这样的组份单元组成,它们... 详细信息

报道了用激光直接溅射法产生钪硫团簇,并用串级飞行时间质谱仪研究了所产生的团簇离子的分布及紫外激光光解规律.钪硫二元团簇正负离子都是由周边硫原子包围团簇骨架而构成的,骨架是由包含着不同数目的Sc_2C_3这样的组份单元组成,它们结合紧密,构成了稳定的钒硫团簇的核心.稳定的团簇正离子为ScS(Sc_2S_3)_n^+和Sc_2S_2(Sc_2S_3)_n^+.稳定的团簇负离子为ScS_2(Sc_2S_3)_n^-,S_3(Sc_2S_3)_n^-(Sc_2S_3)_n^-.周边硫原子数目随样品中硫的摩尔含量的增加而增多,它们结合较弱,易于剥离.在紫外光解时往往以失去S_2,S_4,S_6的方式解离.通过分析认为具有组份单元的Sc对于S团簇的结构可能是一种笼状结构.

关键词：团簇激光光解质谱钪硫团簇硫

Role of the globus pallidus in motor and non-motor symptoms of Parkinson's disease

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Neural Regeneration Research 2025年第6期20卷 1628-1643页

作者： Yimiao Jiang Zengxin qi Huixian zhu Kangli Shen Ruiqi Liu Chenxin Fang Weiwei Lou Yifan Jiang Wangrui Yuan Xin Cao Liang Chen qianxing zhuang Department of Physiology School of MedicineNantong UniversityNantongJiangsu ProvinceChina Department of Neurosurgery Huashan HospitalShanghai Medical CollegeFudan UniversityShanghaiChina National Center for Neurological Disorders ShanghaiChina Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration ShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institute of Brain ScienceFudan UniversityShanghaiChina

The globus pallidus plays a pivotal role in the basal ganglia circuit. Parkinson's disease is characterized by degeneration of dopamine-producing cells in the substantia nigra, which leads to dopamine deficiency in the brain that subsequently manifests as various motor and non-motor symptoms. This review aims to summarize the involvement of the globus pallidus in both motor and non-motor manifestations of Parkinson's disease. The firing activities of parvalbumin neurons in the medial globus pallidus, including both the firing rate and pattern, exhibit strong correlations with the bradykinesia and rigidity associated with Parkinson's disease. Increased beta oscillations, which are highly correlated with bradykinesia and rigidity, are regulated by the lateral globus pallidus. Furthermore,bradykinesia and rigidity are strongly linked to the loss of dopaminergic projections within the cortical-basal ganglia-thalamocortical loop. Resting tremors are attributed to the transmission of pathological signals from the basal ganglia through the motor cortex to the cerebellum-ventral intermediate nucleus circuit. The cortico–striato–pallidal loop is responsible for mediating pallidi-associated sleep disorders. Medication and deep brain stimulation are the primary therapeutic strategies addressing the globus pallidus in Parkinson's disease. Medication is the primary treatment for motor symptoms in the early stages of Parkinson's disease, while deep brain stimulation has been clinically proven to be effective in alleviating symptoms in patients with advanced Parkinson's disease,particularly for the movement disorders caused by levodopa. Deep brain stimulation targeting the globus pallidus internus can improve motor function in patients with tremordominant and non-tremor-dominant Parkinson's disease, while deep brain stimulation targeting the globus pallidus externus can alter the temporal pattern of neural activity throughout the basal ganglia–thalamus network. Therefore, the comp

关键词： anxiety basal ganglia bradykinesia deep brain stimulation depression globus pallidus externus globus pallidus internus lateral globus pallidus medial globus pallidus neural circuit Parkinson's disease

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： Jun Jiang Zhenjie Lu Yanwen Ding Shujun Liu Zhijie qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Ductility

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浅议“宽严相济”刑事政策与促进社会和谐

天津市政法管理干部学院学报 2007年第3期23卷 46-49页

作者：孙学文朱启鹤天津市武清区人民检察院天津武清301700

民主法制更加完善是和谐社会的重要目标,作为国家基本政策之一的刑事法律政策,理应遵循"和谐"目标的要求进行相应的调整。"宽严相济"的刑事政策与和谐社会之间存在着天然的契合关系,适合中国的国情特色和时代特征,对于今后惩治犯罪和遏... 详细信息

民主法制更加完善是和谐社会的重要目标,作为国家基本政策之一的刑事法律政策,理应遵循"和谐"目标的要求进行相应的调整。"宽严相济"的刑事政策与和谐社会之间存在着天然的契合关系,适合中国的国情特色和时代特征,对于今后惩治犯罪和遏制犯罪增多趋势有着很大的作为空间。贯彻"宽严相济"刑事政策,是检察工作落实科学发展观的客观要求,也是促进社会和谐与公正的重要保障,应本着求是务实、区分案情、以法为度,当宽则宽,当严则严,宽以济严,严以济宽,准确把握、慎重从事,力求法律效果、政治效果、社会效果的统一。

关键词：和谐和谐社会宽严相济

Epigenetics in the modern era of crop improvements

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Science China Life Sciences 2025年

作者： Yan Xue Xiaofeng Cao Xiangsong Chen Xian Deng Xingwang Deng Yong Ding Aiwu Dong Chengguo Duan Xiaofeng Fang Lei Gong Zhizhong Gong Xiaofeng Gu Chongsheng he Hang he Shengbo he Xinjian he Yan he Yuehui he Guifang Jia Danhua Jiang Jianjun Jiang Jinsheng Lai Zhaobo Lang Chenlong Li qing Li Xingwang Li Bao Liu Bing Liu Xiao Luo Yijun qi Weiqiang qian Guodong Ren qingxin Song Xianwei Song Zhixi Tian Jiawei Wang Yuan Wang Liang Wu Zhe Wu Rui Xia Jun Xiao Lin Xu Zhengyi Xu Wenhao Yan Hongchun Yang Jixian Zhai Yijing Zhang Yusheng Zhao Xuehua Zhong Daoxiu Zhou Ming Zhou Yue Zhou Bo zhu Jiankang zhu qikun Liu College of Life Sciences Institute of Life Science and Green Development Hebei University Biotechnology Research Institute Chinese Academy of Agricultural Sciences College of Biology Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation Hunan Engineering and Technology Research Center of Hybrid Rapeseed Hunan University Institute of Advanced Agricultural Sciences School of Advanced Agricultural Sciences Peking University State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural University National Institute of Biological Sciences Key Laboratory of Seed Innovation Institute of Genetics and Developmental Biology Chinese Academy of Sciences School of Advanced Agricultural Sciences Peking-Tsinghua Center for Life Sciences Peking University Synthetic and Functional Biomolecules Center Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Key Laboratory of Seed Innovation State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences State Key Laboratory of Wheat Improvement Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory of Advanced Agricultural Sciences in Weifang State Key Laboratory of Crop Stress Adaptation and Improvement School of Life Sciences Henan University State Key Laboratory of Maize Bio-breeding National Maize Improvement Center Department of Plant Genetics and Breeding China Agricultural University Frontiers Science Center for Molecular Design Breeding China Agricultural University Center for Crop Functional Genomics and Molecular Breeding China Agricultural University Sanya Institute of China Agricultural University Hainan Yazhou Bay Seed Laboratory Institute of Advan

Epigenetic mechanisms are integral to plant growth, development, and adaptation to environmental stimuli. Over the past two decades,our comprehension of these complex regulatory processes has expanded remarkably, producing a substantial body of knowledge on both locus-specific mechanisms and genome-wide regulatory patterns. Studies initially grounded in the model plant Arabidopsis have been broadened to encompass a diverse array of crop species, revealing the multifaceted roles of epigenetics in physiological and agronomic traits. With recent technological advancements, epigenetic regulations at the single-cell level and at the large-scale population level are emerging as new focuses. This review offers an in-depth synthesis of the diverse epigenetic regulations, detailing the catalytic machinery and regulatory functions. It delves into the intricate interplay among various epigenetic elements and their collective influence on the modulation of crop traits. Furthermore, it examines recent breakthroughs in technologies for epigenetic modifications and their integration into strategies for crop improvement. The review underscores the transformative potential of epigenetic strategies in bolstering crop performance, advocating for the development of efficient tools to fully exploit the agricultural benefits of epigenetic insights.

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THF/H_2O二元团簇中“幻数”现象研究

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化学学报 2000年第9期58卷 1107-1111页

作者：石土金王栩杨达林朱起鹤盛六四武国华张允武中国科学院化学研究所分子科学中心分子反应动力学国家重点实验室北京100080 中国科学技术大学国家同步辐射实验室合肥230027

利用分子束、同步辐射光源和飞行时间质谱研究了THF/H_2O二元团簇体系,观察到一系列组成为(THF)_n·(H_2O)_mH^+(n=2～5,m=0～n-1)离子峰,其中(THF)_n(H_2O)_(n-2)H^+(n=2～5)离子峰强为“幻数”峰.运用从头算(ab initio)分子轨道法,在H... 详细信息

利用分子束、同步辐射光源和飞行时间质谱研究了THF/H_2O二元团簇体系,观察到一系列组成为(THF)_n·(H_2O)_mH^+(n=2～5,m=0～n-1)离子峰,其中(THF)_n(H_2O)_(n-2)H^+(n=2～5)离子峰强为“幻数”峰.运用从头算(ab initio)分子轨道法,在HF/3-21G基组水平上对(THF)_n(H_2O)_(n-2)H^+(n=2～4)团簇几何构型进行了优化,计算结果表明团簇离子(THF)_n(H_2O)_(n-2)H^+具有较大的稳定性,解释了实验中观察到的“幻数”现象.

关键词：同步辐射光源四氢呋喃 “幻数” 水二元团簇