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The Thermal Decomposition of Calcium Carbonate

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Chinese Chemical Letters 2001年第8期12卷 745-746页

作者： yu Ting zhao tong Shan SUN Bing SUN Department of Chemistry Shandong UniversityJinan 250100

The thermogravimetry(TG) and derivative thermogravimetry(DTG) curves of the thermal decomposition reaction of calcium carbonate have been measured at five different heating rates. The kinetic parameters and the reaction mechanism of the reaction were evaluated from analysis of the TG and DTG curves by using the Ozawa method, the combined integral and differential methods and the reduced equations derived by us.

关键词： Calcium carbonate kinetic parameters non-isothermal kinetics TG-DTG

Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-Bo Li Qi Zhang Jun-zhao Xiao Yi-Fan Wang Tian-yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： Yan zhao Qiang yuan Liting Yang Guisheng Liang Yifeng Cheng Limin Wu Chunfu Lin Renchao Che College of Physics Donghua UniversityShanghai 201620People’s Republic of China School of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization

员工主动性人格与创新行为的关系:基于趋利-避害框架理论的实证研究

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管理工程学报 2025年第2期39卷 41-56页

作者：严鸣赵楚铃朱瑜邬金涛暨南大学管理学院中山大学岭南学院

员工的创新行为能为员工个体和组织带来益处,但同时也会给员工带来较大风险,而现有研究未解决员工在面对潜在风险时仍会表现出创新行为这个问题。本文基于趋利-避害框架理论,通过163个团队的489份数据,探讨了趋利型/避害型主动性人格影... 详细信息

员工的创新行为能为员工个体和组织带来益处,但同时也会给员工带来较大风险,而现有研究未解决员工在面对潜在风险时仍会表现出创新行为这个问题。本文基于趋利-避害框架理论,通过163个团队的489份数据,探讨了趋利型/避害型主动性人格影响员工不同类型创新行为的内在作用机制和边界条件。研究发现,趋利型主动性人格通过机会发掘动机间接影响增益型创新行为,而避害型主动性人格通过问题发掘动机间接影响避害型创新行为。团队内授权氛围不仅会调节趋利型主动人格与机会发掘动机的关系,还会进一步调节趋利型主动型人格通过机会发掘动机间接影响增益型创新行为的关系。同时,团队间竞争氛围可以调节避害型主动人格与问题发掘动机的关系,进一步调节避害型主动型人格通过问题发掘动机间接影响避害型创新行为的关系。本文在理论上有助于澄清主动性人格的实质及其对不同类型创新行为的影响效应和作用机制,为提高企业创新行为管理水平提供管理启示。

关键词：主动性人格创新行为趋利避害框架理论团队内授权氛围团队间竞争氛围

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Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2982-2997页

作者： Hongli Li Jianhua Huang Di zhao Lemei Zhu Zheyu Zhang Min Yi Weijun Peng Department of Integrated Traditional Chinese&Western Medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina National Clinical Research Center for Metabolic Diseases ChangshaHunan ProvinceChina Hunan Academy of Chinese Medicine ChangshaHunan ProvinceChina Academician Workstation Changsha Medical UniversityChangshaHunan ProvinceChina

Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut *** aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease *** do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of ***-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 ***,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 *** findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies.

关键词： Alzheimer’s disease APP/PS1 mice brain-kidney axis gut microbiota heart-brain axis liver-brain axis lung-brain axis microbiota-gut-brain axis peripheral organ metabolism spleen-brain axis

Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases

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Neural Regeneration Research 2025年第8期20卷 2373-2381页

作者： Lifang zhao Mingkai Zhang Qimeng Li Xuemin Wang Jie Lu Ying Han Yanning Cai Department of Clinical Biobank Xuanwu HospitalCapital Medical UniversityBeijingChina Beijing Geriatric Medical Research Center BeijingChina Department of Neurology Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Radiology and Nuclear Medicine Xuanwu HospitalCapital Medical UniversityBeijingChina Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics BeijingChina Key Laboratory of Neurodegenerative diseases Ministry of EducationBeijingChina School of Biomedical Engineering Hainan UniversityHaikouHainan ProvinceChina Center of Alzheimer’s Disease Beijing Institute for Brain DisordersBeijingChina National Clinical Research Center for Geriatric Diseases BeijingChina Institute of Biomedical Engineering Shenzhen Bay LaboratoryGaoke Innovation CenterShenzhenGuangdong ProvinceChina Department of Neurobiology Xuanwu HospitalCapital Medical UniversityBeijingChina

Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative ***,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°*** aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large *** samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline *** samples were stored at-80°C for up to 6 years before being used in this *** results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage ***,the level of total tau showed a negative correlation with sample storage ***,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage *** was not observed in individuals with cognitive ***,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage ***,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's ***,in cohort studies,it is important to consider the impact of storage time on the overall results.

关键词： Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein neurodegeneration neurofilament light chain plasma biomarkers single molecule array storage time tau

Preparation of Phenolic Resin/Silver Nanocomposites via in-situ Reduction

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Chinese Chemical Letters 2003年第4期14卷 426-428页

作者： Lin Jie ZHI Jin yue TANG tong zhao yun zhao yu State Key Laboratory of Engineering Plastics Institute of ChemistryThe Chinese Academy of SciencesBeijing 100080

Resol type phenolic resin/silver nanocomposite was prepared by in-situ reduction method, in which the curing of phenolic resin and the formation of silver nano-particles took place simultaneously. The silver ions were reduced completely to silver nanoparticles, which were dispersed homogeneously in the resin matrix with narrow size distribution.

关键词： Nanocomposite silver nanoparticle phenolic resin in-situ reduction.

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达卡巴嗪分子拉曼和紫外吸收光谱的理论研究

原子与分子物理学报 2025年第1期42卷 49-53页

作者：陈玉锋陈慧任黎英赵宁韩金玲李雨桐牡丹江师范学院化学化工学院黑龙江省光电功能材料重点实验室牡丹江157011

采用密度泛函理论(Density functionol theory,DFT),在B3LYP/6-31+g(d,p)基组水平上,对达卡巴嗪进行了结构优化,通过频率计算,获得达卡巴嗪的拉曼光谱,与实验获得的拉曼光谱进行对比,对400~2000 cm^(-1)频率范围内的拉曼光谱特征峰进行... 详细信息

采用密度泛函理论(Density functionol theory,DFT),在B3LYP/6-31+g(d,p)基组水平上,对达卡巴嗪进行了结构优化,通过频率计算,获得达卡巴嗪的拉曼光谱,与实验获得的拉曼光谱进行对比,对400~2000 cm^(-1)频率范围内的拉曼光谱特征峰进行了指认归属.计算分析前线分子轨道和表面静电势,预测了达卡巴嗪分子化学反应发生的位点.采用含时密度泛函理论(Time-dependent density functional theory,TDDFT)计算了该分子的紫外吸收光谱和激发态,获得电荷转移光谱,分析了达卡巴嗪分子间的电荷转移关系.

关键词：密度泛函理论达卡巴嗪拉曼光谱紫外光谱

Potential role and therapeutic implications of glutathione peroxidase 4 in the treatment of Alzheimer's disease

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Neural Regeneration Research 2025年第3期20卷 613-631页

作者： Yanxin Shen Guimei Zhang Chunxiao Wei Panpan zhao Yongchun Wang Mingxi Li Li Sun Department of Neurology and Neuroscience Center The First Hospital of Jilin UniversityJilin UniversityChangchunJilin ProvinceChina Cognitive Impairment Center Department of NeurologyThe First Hospital of Jilin UniversityJilin UniversityChangchunJilin ProvinceChina

Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxidative stress mediates excessive oxidative responses, and its involvement in Alzheimer's disease pathogenesis as a primary or secondary pathological event is widely accepted. As a member of the selenium-containing antioxidant enzyme family, glutathione peroxidase 4 reduces esterified phospholipid hydroperoxides to maintain cellular redox homeostasis. With the discovery of ferroptosis, the central role of glutathione peroxidase 4 in anti-lipid peroxidation in several diseases, including Alzheimer's disease, has received widespread attention. Increasing evidence suggests that glutathione peroxidase 4 expression is inhibited in the Alzheimer's disease brain, resulting in oxidative stress, inflammation, ferroptosis, and apoptosis, which are closely associated with pathological damage in Alzheimer's disease. Several therapeutic approaches, such as small molecule drugs, natural plant products, and non-pharmacological treatments, ameliorate pathological damage and cognitive function in Alzheimer's disease by promoting glutathione peroxidase 4 expression and enhancing glutathione peroxidase 4 activity. Therefore, glutathione peroxidase 4 upregulation may be a promising strategy for the treatment of Alzheimer's disease. This review provides an overview of the gene structure, biological functions, and regulatory mechanisms of glutathione peroxidase 4, a discussion on the important role of glutathione peroxidase 4 in pathological events closely related to Alzheimer's disease, and a summary of the advances in small-molecule drugs, natural plant products, and non-pharmacological therapies targeting glutathione peroxidase 4 for the treatment of Alzheimer's disease. Most prior studies on this subject used animal models, and relevant clinical studies are lacking. Future clinica

关键词： apoptosis ferroptosis inflammation lipid peroxidation natural plant products neurodegenerative disorder neuroprotection oxidative stress small-molecule drugs