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A Monte Carlo Study of the Evolution of the Scale Height of Normal Pulsars in the Galaxy

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Chinese Journal of Astronomy and Astrophysics 2005年第6期5卷 610-618页

作者： Ying-chun Wei Xin-ji wu Qiu-He Peng Na Wang jin Zhang National Astronomical Observatories/Urumqi Observatory Chinese Academy of SciencesUrumqi 830011 Department of Astronomy Peking University Beijing 100871 Department of Astronomy Nanjing University Nanjing 210093

Based on the undisturbed, finite thickness disk gravitational potential, we carried out 3-D Monte Carlo simulations of normal pulsars. We find that their scale height evolves in a similar way for different velocity dispersions （δv）： it first increases linearly with time, reaches a peak, then gradually decreases, and finally approaches a stable asymptotic value. The initial velocity dispersion has a very large influence on the scale height. The time evolution of the scale height is studied. When the magnetic decay age is used as the time variable, the observed scale height has a similar trend as the simulated results in the linear stage, from which we derive velocity dispersions in the range 70 - 178km s^-1, which are near the statistical result of 90 - 270km s^-1 for 92 pulsars with known transverse velocities. If the characteristic age is used as the time variable, then the observed and theoretical curves roughly agree for t 〉 10^8 yr only if av 〈 25km s^-1.

关键词： pulsar general - stars evolution - Galaxy structure - Galaxy disk

Palladium-Catalyzed Intramolecular Dehydrogenative Arylboration of Alkenes

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Chinese Journal of Chemistry 2022年第20期40卷 2437-2444页

作者： Chenchen Zou Hongli wu Yuqi ji Penglin Zhang Huanhuan Cui Genping Huang chun Zhang Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic ScienceDepartment of ChemistrySchool of ScienceTianjin UniversityTianjin300072 China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin300071 China

The palladium-catalyzed borylative cyclization via C—H activation has been *** this chemistry,the indole-fused dihydro-pyrrole motif,which is a kind of important unit in natural products and bio-active molecules,could be constructed and installed with a boric ester ***,the utilities of products have been illustrated by the study of further ***,by using chiral ligand,the enantioselectivity of this borylative cyclization reaction could be ***,the borylative mechanism,which should proceed through a Pd(II)/Pd(IV)catalytic cycle,has been proposed based on the DFT calculations.

关键词： Palladium Dehydrogenative coupling reaction Indole-fused dihydro-pyrrole Boron

PEDOT:Fundamentals and Its Nanocomposites for Energy Storage

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Chinese Journal of Polymer Science 2020年第5期38卷 435-448,I0005页

作者： Hong-wu Chen chun Li Department of Chemistry Ministry of Education Key Laboratory ofBioorganic Phosphorous Chemistry and Chemical BiologyTsinghua UniversityBeijing 100084China

PEDOT,or poly(3,4-ethylenedioxythiophene),is among the most successful conducting polymer products because of its stable conductivity,colloidal processability,and rich assembly *** the very first patents on PEDOT filed in 1988,the material has been widely explored for decades in many *** this review,a comprehensive summary on the synthesis,processing and post-treatment of PEDOT will be presented for the sake of the discussion on PEDOT and its nanocomposites for energy *** what PEDOT lends itself to the electrode materials is of importance to the rational design of energy storage devices that maximize the real-world *** on these discussions,a roadmap for the development of PEDOT as promising multifunctional electrode component is presented.

关键词： PEDOT Energy storage Nanomaterials Capacitor Battery

The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study

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Neural Regeneration Research 2025年第5期20卷 1505-1512页

作者： jieying wu Shan Ye Xiangyi Liu Yingsheng Xu Dongsheng Fan Department of Neurology Peking University Third HospitalBeijingChina Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases BeijingChina Key Laboratory for Neuroscience National Health Commission/Ministry of EducationPeking UniversityBeijingChina

Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor *** bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to ***,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is *** address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral *** used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis *** factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb *** results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis *** findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.

关键词： amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread

A mild, configurable, flexible CoNi-LDH（v）/Zn battery based on H-vacancy-induced reversible Zn2+ intercalation

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Journal of Energy Chemistry 2025年第1期100卷 498-508页

作者： Xinyue Cheng Dingsheng wu Hao Gao Qingqing Wang Pengfei Lv Sam S.Yoon Qufu Wei Key Laboratory of Eco-textiles Ministry of Education Jiangnan University School of Mechanical Engineering Korea University

Flexible Zn-based batteries have attracted increasing research interest as essential components of wearable energy storage ***,the advancement of flexible aqueous Zn-based batteries based on Co-Ni layered double hydroxide （CoNi-LDH） as the cathode material is hampered by their poor cycling stability and the corrosiveness of alkaline ***,CoNi-LDH nanosheets enriched with H vacancies (CoNi-LDH（v）) were constructed on a flexible carbon cloth （CC） substrate via electrochemical deposition and *** Zn-based battery comprising CoNi-LDH（v）@CC as the cathode exhibited highly reversible conversion reactions and stable operation in 3 M ZnSO4electrolyte （pH=4）.The battery delivered an excellent specific capacity (225 mA h g-1,0.26 mA h cm-2),acceptable cycling stability（53.9%,900 cycles）,and high discharging *** abundant H vacancies served as active sites for the reversible intercalation of Zn2+and the extravasation of NO3-generated channels and space for Zn2+transport and storage,together enabling an excellent Zn2+storage ***,a sandwich-structured solid-state CoNi-LDH（v）@CC//Zn@CC battery was fabricated and was found to exhibit a noteworthy electrochemical performance and mechanical *** a proof of concept,the unencapsulated battery powered a digital watch under various deformation conditions and operated stably for 80 ***,the flexible battery displayed outstanding customizability,maintaining an open-circuit voltage of 1.42 V even after being cut *** proposed engineering strategy contributes to the realization of textiles with truly wearable energy-storage devices.

关键词： CoNi/Zn battery H vacancies Mild aqueous electrolyte Tailorable battery Wearable energy storage device

Glycolytic dysregulation in Alzheimer's disease:unveiling new avenues for understanding pathogenesis and improving therapy

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Neural Regeneration Research 2025年第8期20卷 2264-2278页

作者： You wu Lijie Yang Wanrong jiang Xinyuan Zhang Zhaohui Yao Department of Geriatrics Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Alzheimer's disease poses a significant global health challenge owing to the progressive cognitive decline of patients and absence of curative *** current therapeutic strategies,primarily based on cholinesterase inhibitors and N-methyl-Daspartate receptor antagonists,offer limited symptomatic relief without halting disease progression,highlighting an urgent need for novel research directions that address the key mechanisms underlying Alzheimer's *** studies have provided insights into the critical role of glycolysis,a fundamental energy metabolism pathway in the brain,in the pathogenesis of Alzheimer's *** in glycolytic processes within neurons and glial cells,including microglia,astrocytes,and oligodendrocytes,have been identified as significant contributors to the pathological landscape of Alzheimer's *** changes impact neuronal health and function,thus offering promising targets for therapeutic *** purpose of this review is to consolidate current knowledge on the modifications in glycolysis associated with Alzheimer's disease and explore the mechanisms by which these abnormalities contribute to disease onset and *** focus on the pathways through which glycolytic dysfunction influences Alzheimer's disease pathology should provide insights into potential therapeutic targets and strategies that pave the way for groundbreaking treatments,emphasizing the importance of understanding metabolic processes in the quest for clarification and management of Alzheimer's disease.

关键词： Alzheimer’s disease glial cells glycolysis neuronal metabolism pathogenesis therapeutic targets

A new horizon for neuroscience:terahertz biotechnology in brain research

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Neural Regeneration Research 2025年第2期20卷 309-325页

作者： Zhengping Pu Yu wu Zhongjie Zhu Hongwei Zhao Donghong Cui Shanghai Key Laboratory of Psychotic Disorders Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Department of Psychiatry Kangci Hospital of JiaxingTongxiangZhejiang ProvinceChina Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghaiChina Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of ScienceShanghaiChina National Facility for Protein Science in Shanghai Shanghai Advanced Research InstituteChinese Academy of SciencesShanghaiChina

Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain *** this article,we review the development of terahertz biotechnology and its applications in the field of *** evidence indicates promising prospects for the use of terahertz spectroscopy and terahertz imaging techniques in the diagnosis of amyloid disease,cerebrovascular disease,glioma,psychiatric disease,traumatic brain injury,and myelin *** vitro and animal experiments have also demonstrated the potential therapeutic value of terahertz technology in some neuropsychiatric *** the precise underlying mechanism of the interactions between terahertz electromagnetic waves and the biosystem is not yet fully understood,the research progress in this field shows great potential for biomedical noninvasive diagnostic and therapeutic ***,the biosafety of terahertz radiation requires further exploration regarding its two-sided efficacy in practical *** review demonstrates that terahertz biotechnology has the potential to be a promising method in the field of neuropsychiatry based on its unique advantages.

关键词： biological effect brain neuron neuropsychiatry neuroscience non-thermal effect terahertz imaging terahertz radiation terahertz spectroscopy terahertz technology

Effect of droplet heat content distribution on humping formation in high speed GMAW

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Acta Metallurgica Sinica(English Letters) 2011年第6期24卷 457-465页

作者： ji CHEN Chuansong wu MOE Key Laboratory for Liquid-Solid Structure Evolution and Materials Processing Institute of Materials Joining Shandong University Jinan 250061 China State Key Laboratory for Advanced Welding ＆ Joining Harbin Institute of Technology Harbin 150001 China BAM Federal Institute for Materials Research and Testing Division V.5 Safety of Joined Components Berlin 12205 Germany

The momentum of strong backward flowing melt jet and the thermal action from transferred droplets are two dominating factors affecting the formation of humping bead in high speed gas metal arc welding （GMAW）. Appropriate describing the influ- ence of the distribution mode of droplet heat content in the weld pool is essential to understand the physical mechanism of humping bead formation. Based on the exper- imental results, four kinds of droplet heat content distribution modes are proposed and employed to calculate the transient evolution of the temperature field and weld pool during high speed GMAW process. Through making comparison of predicted and measured weld bead dimensions, a suitable and adaptive distribution mode of droplet heat content is found, i.e., droplet heat content is distributed in bottom layer of gouging region at the front of weld pool, and is averagely distributed in the whole layer at the rear of weld pool. The proposed mode is also validated by experimental observation of the weld pool images and measured by geometric dimensions of the weld bead.

关键词： High speed GMAW Hump forming mechanism Droplet heat content Numerical analysis

Metapelitic Garnet-Muscovite-Al_2SiO_5-Quartz(GMAQ) Geothermobarometry

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Journal of Earth Science 2018年第5期29卷 977-988页

作者： chun-Ming wu College of Earth and Planetary Sciences University of Chinese Academy of Sciences

The garnet-muscovite geothermometer and garnet-muscovite-Al2SiO5 -quartz （GMAQ） geobarometer have been empirically calibrated under P-T conditions of 1-12 kbar and 460-760 ℃ using natural metapelitic rocks. The chemical compositions of the calibrant muscovite are in the ranges of Fe=0.03-0.21 atoms, Mg=0.02-0.32 atoms and AI VI=1.62-1.96 atoms, respectively, on the ll-oxygen basis per formula unit. The garnet-muscovite thermometer yields similar temperature estimates to the well calibrated garnet-biotite thermometer within error of 4-55 ℃, and successfully discriminates the systematic temperature change of the different zones of either the prograde or inverted metamorphic terranes or thermal contact aureoles. The six formulations of GMAQ barometry yield similar pressure estimates to the well calibrated GASP barometer within error of ±1.2 kbar, and plot the Al2SiOs-bearing metapelite into the correct stability field of the AI2SiOs polymorphs. Moreover, the GMAQ thermobarometers show that the pressure is almost constant for every thermal contact aureole within limited geographic region, which reflects geological condition. The random errors are estimated to be of ca. 4-60 ℃ and 4-1.4 kbar for the geothermometer and geobarometer, respectively. A spreadsheet for applying GMAQ geothermo- barometry is supplied in the Electronic Supplementary Materials.

关键词： Al2SiO5 application calibration garnet geothermobarometry muscovite.