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Fast Growth of Polycrystalline 3C-SiC on Si （100） by High Temperature Carbonization Process

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Fast Growth of Polycrystalline 3C-SiC on Si （100） by High ...

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

2002年中国材料研讨会

作者： L. Wang G. S. Sun W. S. Zhao m. C. Luo Y. L. Sun j. m. li Y. P. Zeng L.Y. lin (Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, P. R. China)

＜正＞ Growth of polycrystalline 3C-SiC on S i（100） substrate was carried out at substrate temperature of about 1450℃, which is higher than the melting point of Si substrate, by carbonization process in a horizontal CVD chamber. The growth rate is about 30 - 40 μm/h. The average grain size ranges from 2 -15 μm and most of the grains have the different oriental from the Si （100） substrate. X-ray diffraction patterns have confirmed that 3C-SiC polycrystals were obtained. The surface morphology and the back-side interface morphology of 3C-SiC were investigated by using scanning electron microscope. The crystallinity was investigated by the plane view transmission electron microscope. This work provides a possible method for preparation of pure SiC source materials used for modified Lely method.

关键词： 3C-SiC polycrystal carbonization process

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International journal of minerals,metallurgy and materials 2025年第1期32卷 127-135页

作者： Tongyue li Ziliang Xie Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping Song State Key Laboratory for Advanced metals and materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/m(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kj·mol^(-1)and an entropy change(ΔS)of-119.14 j·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kj·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/m was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/m ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

Reversing anther thermotolerance by manipulating the cis-elements in the promoter of a high-temperature upregulated gene Casein Kinase I in upland cotton

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Science China life Sciences 2025年

作者： Yanlong li Yinuo Fu Yaoyao li Rui Zhang jing Yang Huanhuan ma ling min Xianlong Zhang National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University

High temperature (HT) stress causes male sterility,leading to reduced upland cotton ***,we identified a key gene,Casein Kinase I (GhCKI),that negatively regulates male fertility in upland cotton under ***,conventional genetic manipulations of GhCKI would result in male sterility,hindering its utilization in breeding ***,we engineered quantitative variation for anther thermotolerance-related traits in upland cotton by creating weak promoter alleles of GhCKI genes,using CRISPR/Cas9 and CRISPR/Cpf1genome ***,we screened and identified two new upland cotton plant lines exhibiting a HT-tolerant phenotype with edited GhCKI promoters,and characterized their corresponding heat-tolerant allelic *** research revealed that the primary reason for the HT tolerance of the GhCKI promoter editing mutants is that the trans-acting factors GhmYB73 and GhmYB4,which positively regulate GhCKI expression under HT,failed to bind and activate the expression of ***,our study not only provides a rapid strategy to generate new beneficial alleles but also offers novel germplasm resources and molecular insights for crop HT tolerance breeding.

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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

liver as a new target organ in Alzheimer's disease:insight from cholesterol metabolism and its role in amyloid-beta clearance

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Neural Regeneration Research 2025年第3期20卷 695-714页

作者： Beibei Wu Yuqing liu Hongli li Lemei Zhu lingfeng Zeng Zhen Zhang Weijun Peng Department of Integrated Traditional Chinese&Western medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Academician Workstation Changsha Medical UniversityChangshaHunan ProvinceChina Yangsheng College of Traditional Chinese medicine Guizhou University of Traditional Chinese MedicineGuiyangGuizhou ProvinceChina Qinhuangdao Shanhaiguan Pharmaceutical Co. LtdQinhuangdaoHebei ProvinceChina National Clinical Research Center for mental Disorder The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

Alzheimer's disease,the primary cause of dementia,is characterized by neuropathologies,such as amyloid plaques,synaptic and neuronal degeneration,and neurofibrillary *** amyloid plaques are the primary characteristic of Alzheimer's disease in the central nervous system and peripheral organs,targeting amyloid-beta clearance in the central nervous system has shown limited clinical efficacy in Alzheimer's disease *** abnormalities are commonly observed in patients with Alzheimer's *** liver is the primary peripheral organ involved in amyloid-beta metabolism,playing a crucial role in the pathophysiology of Alzheimer's ***,impaired cholesterol metabolism in the liver may exacerbate the development of Alzheimer's *** this review,we explore the underlying causes of Alzheimer's disease and elucidate the role of the liver in amyloid-beta clearance and cholesterol ***,we propose that restoring normal cholesterol metabolism in the liver could represent a promising therapeutic strategy for addressing Alzheimer's disease.

关键词： ABCA1 Alzheimer's disease amyloid-beta apolipoprotein E cholesterol metabolism liver liver X receptor low-density lipoprotein receptor-related protein 1 peripheral clearance tauroursodeoxycholic acid

Unraveling post-growth mechanisms of monolayer CsPbBr3 nanocubes:Laser-enhanced transformations and cathodoluminescence-electron microscopy correlations

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journal of Energy Chemistry 2025年第1期100卷 146-156页

作者： mingxing li Xiaoge Wang Xiaofan Cao Zhiqun He Chunjun liang mingxing Chen jing ju Fangtian You Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic Technology Beijing Jiaotong University Beijing National Laboratory for molecular Sciences (BNLmS) College of Chemistry and Molecular Engineering Peking University

Lead-halide perovskite nanoparticles（LHP NPs） are highly promising materials for next-generation displays and solid-state lighting due to their exceptional optical properties. However, their inherent instability presents a significant challenge. Recent advances have demonstrated that optoelectronic devices based on monolayer nanoparticle films exhibit both high luminescence efficiency and long-term *** research demonstrates that mobility limitations and anisotropic alignments in CsPbBr3nanocube monolayer films are key to their stabilization, hindering spontaneous growth through face-to-face fusion and resulting in the formation of connecting necks in a diagonal direction. Introducing laser irradiation confirmed this by significantly accelerating nanocubes growth, increasing mobility, and enhancing local structural ordering, leading to larger and more regularly shaped nanosheets. Fourier transform infrared spectroscopy and energy dispersive spectroscopy line-scan analyses indicated that laser irradiation did not disrupt the ligand structure. Transmission electron microscopy and correlative cathodoluminescence electron microscopy revealed the effects of post-growth and heterogeneous structures, including enhanced luminescence and inhomogeneous intensity in the nanosheets. These findings deepen the understanding of the post-growth mechanism of monolayer nanoparticles and the structure-emission correlation and highlight the unique role of laser irradiation in directing the formation of well-defined and regular nanostructures.

关键词： Energy dispersive spectroscopy

High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

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journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun Zhang Xiaoyun Wang Shuai Wang Yan li libo Chen Handong jiao Zhijing Yu jiguo Tu State Key Laboratory of Advanced metallurgy University of Science and Technology Beijing Research Institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Institute of Advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (limnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** limnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of limnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of limnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable limnxFe1-xPO4materials,to achieve practical energy storage requirements.

关键词： Semiconductor doping

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期 233-240页

作者： Peipei liu Yantong li meng-Xiang Wu Hao Kang Xiao-li Zhao lin Xu linlin liu Xiaodong li junfeng Fang Zhiwei Fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/mm and 1-Pm, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/mm was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-mm were characterized by circular dichroism. Interestingly, it was found that 1-PP/mm could be completely isomerized to 1-Pm upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-Pm exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-Pm by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m j cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

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mechanism of inflammatory response and therapeutic effects of stem cells in ischemic stroke:current evidence and future perspectives

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Neural Regeneration Research 2025年第1期20卷 67-81页

作者： Yubo Wang Tingli Yuan Tianjie Lyu ling Zhang meng Wang Zhiying He Yongjun Wang Zixiao li Vascular Neurology Department of NeurologyBeijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Shanghai Engineering Research Center of Stem Cells Translational medicine ShanghaiChina National Center for Healthcare Quality management in Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Institute for Regenerative medicine Shanghai East HospitalSchool of Life Sciences and TechnologyTongji UniversityShanghaiChina Chinese Institute for Brain Research BeijingChina Research Unit of Artificial Intelligence in Cerebrovascular Disease Chinese Academy of Medical SciencesBeijingChina Beijing Engineering Research Center of Digital Healthcare for Neurological Diseases BeijingChina

Ischemic stroke is a leading cause of death and disability worldwide,with an increasing trend and tendency for onset at a younger ***,in particular,bears a high burden of stroke *** recent years,the inflammatory response after stroke has become a research hotspot:understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its *** review summarizes several major cells involved in the inflammatory response following ischemic stroke,including microglia,neutrophils,monocytes,lymphocytes,and ***,we have also highlighted the recent progress in various treatments for ischemic stroke,particularly in the field of stem cell ***,understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient *** cell therapy may potentially become an important component of ischemic stroke treatment.

关键词： cell therapy immune cell inflammatory ischemic stroke stem cell