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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： Xu Liu xun wang Dingyong wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the *** this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at *** in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric *** showed that distinct variabilities among Masson pine tree-ring Hg concentration *** Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric *** found a distinct age effect that the tree ring of young trees had the higher Hg ***,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree *** modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in *** finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： Masson pine Tree-ring mercury Radial translocation Tree age effect

Modified electronic structure and enhanced hydroxyl adsorption make quaternary Pt-based nanosheets efficient anode electrocatalysts for formic acid-/alcohol-air fuel cells

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Journal of Energy Chemistry 2024年第5期92卷 142-150页

作者： Fengling Zhao Qiang Yuan Siyang Nie Liang Wu xun wang State-Local Joint Laboratory for Comprehensive Utilization of Biomass Center for R&D of Fine ChemicalsCollege of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025GuizhouChina Key Lab of Organic Optoelectronics&Molecular Engineering Tsinghua UniversityBeijing 100084China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Surface/interface engineering of a multimetallic nanostructure with diverse electrocatalytic properties for direct liquid fuel cells is desirable yet ***,using visible light,a class of quaternary Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)ultrathin nanosheets is fabricated and used as high-performance anode electrocatalysts for formic acid-/alcohol-air fuel *** modified electronic structure of Pt,enhanced hydroxyl adsorption,and abundant exterior defects afford Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C high intrinsic anodic electrocatalytic activity to boost the power densities of direct formic acid-/methanol-/ethanol-/ethylene glycol-/glycerol-air fuel cells,and the corresponding peak power density of Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C is respectively 129.7,142.3,105.4,124.3,and 128.0 mW cm^(-2),considerably outperforming Pt/*** in situ Fourier transform infrared reflection spectroscopy reveals that formic acid oxidation on Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C occurs via a CO_(2)-free direct *** functional theory calculations show that the presence of Ag,Bi,and Te in Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)suppresses CO^(*)formation while optimizing dehydrogenation steps and synergistic effect and modified Pt effectively enhance H_(2)O dissociation to improve electrocatalytic *** synthesis strategy can be extended to 43 other types of ultrathin multimetallic nanosheets(from ternary to octonary nanosheets),and efficiently capture precious metals(i.e.,Pd,Pt,Rh,Ru,Au,and Ag)from different water sources.

关键词： Pt-based nanosheets Modifiedelectronic structure Enhanced hydroxyl adsorption Formicacidand alcohol oxidation Direct liquid fuel cells

Versatile Organogels of Aluminum Oxide Subnanosheets for Locking Solvents and Adhesion

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Precision Chemistry 2024年第1期2卷 21-27页

作者： Wanyue Ouyang xun wang Key Lab of Organic Optoelectronics and Molecular Engineering Department of ChemistryTsinghua UniversityBeijing 100084China

Herein,we present a facile strategy to prepare versatile aluminum oxide subnanometer nanosheets with oleic acid and stearic acid ligands(OA-Al SNSs and SA-Al SNSs,respectively).The size effect endows subnanosheets with abundant acting sites,remarkable intermolecular interactions,and unique polymer-like properties,including flexibility,viscoelasticity,and sol-gel transitions,which is quite different from traditional inorganic ***,subnanosheets could form freestanding organogels and OA-Al SNSs exhibit satisfying semisolidification of various solvents,making it an intriguing candidate for the safe storage and transportation of ***,SA-Al SNSs exhibit excellent adhesive properties of high strength on diverse substrates,and it is easy to erase it without any damage,demonstrating the promising prospects in practical applications.

关键词： subnanometer nanomaterials self-assembly polymer-analogue organogel adhesive

Robust neutralization of SARS-CoV-2 variants including JN.1 and BA.2.87.1 by trivalent XBB vaccine-induced antibodies

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2359-2361页

作者： xun wang Shujun Jiang Wentai Ma Yanliang Zhang Pengfei wang Shanghai Pudong Hospital Fudan University Pudong Medical CenterState Key Laboratory of Genetic EngineeringMOE Engineering Research Center of Gene TechnologySchool of Life SciencesShanghai Institute of Infectious Disease and BiosecurityFudan UniversityShanghaiChina Department of Infectious Diseases Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese MedicineNanjing Research Center for Infectious Diseases of Integrated Traditional Chinese and Western MedicineNanjingJiangsuChina Beijing Institute of Genomics Chinese Academy of SciencesUniversity of Chinese Academy of Sciences and China National Center for BioinformationBeijingChina

Dear Editor,The rapid and widespread transmission of SARS-CoV-2 has led to the emergence of multiple variants of concern(VOCs),most notably the Omicron variant,which continues to evolve and diversify into a range of *** previous research has shown that these Omicron sub-lineages,spanning BA.1-BA.2.86,have been evolving to exhibit increased neutralization escape capabilities.

关键词： evolve neutralization variants

A Structural Measurement of the Valuation Effect of China's External Assets:Method and Application

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China & World Economy 2024年第2期32卷 97-124页

作者： Guowei Cai Xiaowei Chen xun wang Lingnan College Sun Yat-sen UniversityChina China Center for Economic Research National School of DevelopmentPeking UniversityChina

Existing research on the measurement of the valuation effect mainly follows the residual method proposed by Lane and Milesi-Ferretti(2001).This cannot be used to perform structural *** propose an aggregation approach rather than the residual method to measure structurally the investment flow and valuation effect of China's external *** results indicate that the valuation effect of China's external assets has been highly volatile and it was negative during the pandemic *** structural decomposition shows that portfolio investment and direct investment made the main contributions to the valuation *** impact of exchange rates on the valuation effect has generally been higher than that of asset price in terms of direct investment and total external assets but the opposite has been true for portfolio ***'s outward investments are currently more inclined to Asian countries and a few European countries but inflows to China still mainly come from developed countries.

关键词： external asset investment direction structural measurement valuation effect

Real-time identification of multiple nanoclusters with a protein nanopore in single-cluster level

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Nano Research 2024年第1期17卷 262-269页

作者： Ling Zhang Peilei He Huang Chen Qingda Liu Libo Li xun wang Jinghong Li Department of Chemistry Center for BioAnalytical ChemistryKey Laboratory of Bioorganic Phosphorus Chemistry&Chemical BiologyTsinghua UniversityBeijing 100084China School of Chemistry and Chemical Engineering Guangdong Prov Key Lab Green Chem Prod TechnolSouth China University of TechnologyGuangzhou 510640China New Cornerstone Science Laboratory Shenzhen 518054China Beijing Institute of Life Science and Technology Beijing 102206China Center for BioAnalytical Chemistry Hefei National Laboratory of Physical Science at MicroscaleUniversity of Science and Technology of ChinaHefei 230026China

It is important and challenging to analyze nanocluster structure with atomic ***,α-hemolysin nanopore was used to identify nanoclusters at the single molecule level by providing two-dimensional(2D)dwell time–current blockage spectra and translocation event frequency which sensitively depended on their *** such as Anderson,Keggin,Dawson,and a few lacunary Dawson polyoxometalates with very similar structures,even with only a two-atom difference,could be *** nanopore device could simultaneously measure multiple nanoclusters in a mixture qualitatively and ***,molecular dynamics(MD)simulations provided microscopic understandings of the nanocluster translocation dynamics and yielded 2D dwell time–current blockage spectra in close agreement with *** nanopore platform provides a novel powerful tool for nanocluster characterization.

关键词： nanopore single-molecule nanocluster polyoxometalates real-time detection

Control of GaN inverted pyramids growth on c-plane patterned sapphire substrates

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Journal of Semiconductors 2024年第6期45卷 92-96页

作者： Luming Yu xun wang Zhibiao Hao Yi Luo Changzheng Sun Bing Xiong Yanjun Han Jian wang Hongtao Li Lin Gan Lai wang Beijing National Research Center for Information Science and Technology Department of Electronic EngineeringTsinghua UniversityBei-jing 100084China Center for Flexible Electronics Technology Tsinghua UniversityBeijing 100084China

Growth of gallium nitride(GaN)inverted pyramids on c-plane sapphire substrates is benefit for fabricating novel devices as it forms the semipolar *** this work,GaN inverted pyramids are directly grown on c-plane patterned sapphire substrates(PSS)by metal organic vapor phase epitaxy(MOVPE).The influences of growth conditions on the surface morphol-ogy are experimentally studied and explained by Wulff *** competition of growth rate among{0001},{1011},and{1122}facets results in the various surface morphologies of GaN.A higher growth temperature of 985 ℃ and a lowerⅤ/Ⅲratio of 25 can expand the area of{}facets in GaN inverted *** the other hand,GaN inverted pyramids with almost pure{}facets are obtained by using a lower growth temperature of 930℃,a higherⅤ/Ⅲratio of 100,and PSS with pattern arrangement perpendicular to the substrate primary flat.

关键词： inverted pyramids GaN MOVPE crystal growth competition model

Exploring the vital role of microglial membrane receptors in Alzheimer’s disease pathogenesis: a comprehensive review

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BIOCELL 2024年第7期48卷 1011-1022页

作者： JUN-FENG ZHAO YI-RAN JIANG TIAN-LIN GUO YONG-QING JIAO xun wang Department of Neurointervention Center Dalian No.3 People’s HospitalDalian Medical UniversityDalianChina Department of Clinical Medicine China Medical UniversityShenyangChina

Neurodegenerative diseases constitute a broad category of diseases caused by the degeneration of the *** are mainly manifested by the gradual loss of neuron structure and function and eventually can cause death or loss of *** the global population ages rapidly,increased people are being diagnosed with neurodegenerative *** has been established that the onset of Alzheimer’s disease(AD)is closely linked with increasing age and its major pathological features include amyloid-beta plaques(Aβ),Tau hyperphosphorylation,Neuroﬁbrillary tangles(NFTs),neuronal death as well as synaptic *** involvement of microglia is crucial in the pathogenesis and progression of AD and exhibits a dual *** instance,in the early stage of AD,microglia surface membrane proteins or receptors can participate in immunophagocytosis,and anti-inﬂammatory functions and act as a physical barrier after recognizing various ligands such as Aβand ***,in the later stage of the disease,membrane receptors on the surface of microglia can cause its activation to release a substantial quantity of pro-inﬂammatory *** can amplify the neuroinﬂammatory *** rapid decline of normal immune phagocytosis can result in the continuous accumulation of abnormal proteins,leading to neuronal dysfunction and destruction of the formed physical barrier as well as the neurovascular *** can also increase the transformation of microglia from anti-inﬂammatory phenotype M2 to pro-inﬂammatory phenotype M1,induce severe neuronal injury or apoptosis,and aggravate the progression of *** to few articles have focused on the AD-related membrane protein receptors on microglia,thus in this paper,we have reviewed several representative microglial membrane proteins or receptors about their speciﬁc roles and functions implicated in AD,and expect that there will be more in-depth research and scientiﬁc research results in the treatment of AD by targeted regulation of mi

关键词： Neurodegeneration Glial cell Receptor Alzheimer’s disease

Impact of fluorine on crystal-melt separation in high-silica magma: Insights from muscovite in the Ramba leucogranite of Tethyan Himalaya

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Journal of Earth Science 2024年

作者： Li-Ran Chen wang-Chun Xu Lian-xun wang Hong-Fei Zhang Wuhan State Key Laboratory of Geological Processes and Mineral Resources， and School of Earth Sciences， China University of Geosciences

The process of crystal-melt separation in the high-silica magmatic mush is still a subject of debate. To explore the process， we conducted a detailed study of Late Miocene leucogranites (SiO2＞70 wt.%) in the Ramba Dome of the Tethyan Himalaya， focusing on the genesis and fluorine content of muscovite. The Ramba leucogranites consist of two-mica granite with minor garnet-bearing granite. Large and euhedral muscovites are found in both types of granite exhibiting different geochemical features. The muscovites from the two-mica granites exhibit lower F (mean value: ～0.41–0.43 wt.%)， FeO (mean value: ～1.75–1.81 wt.%)， but higher TiO2(mean value: ～0.61–0.73 wt.%) contents compared to those from the garnet-bearing granites (mean F value: ～0.72%; mean FeO value: 2.48 wt.%; mean TiO2value: ～0.23 wt.%). According to geochemical criteria， we categorized the muscovites from the two-mica granite as two groups: (1) crystallized from the early magma， and (2) formed from interstitial residual melt. In comparison， the muscovite from the garnet-bearing granite was likely crystallized from residual melt extracted from the same magmatic reservoir which underwent a higher degree of evolution. Accordingly， the two-mica granite represents the residual crystal mush consisting of early crystals crystallized from magma and trapped interstitial residual melt， while the garnet-bearing granite represents the aggregation of extracted residual melt. We examined the possibility of crystal-melt separation by estimating the variation of fluorine content and viscosity between the early magma and residual melt. Our results indicate a notable disparity in fluorine content between the residual melt (mean value: ～4364 ppm) and the early magma (mean value: ～2033 ppm). As a result， the estimated viscosity experiences a reduction from 106.52Pa s for the early magma to 105.87Pa s for the residual melt. The fluorine enrichment could have played a critical role in decreasing melt viscosity and initiating crys

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以改革促发展、以实干显情怀——北京大学药学院人才队伍建设的探索和实践

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Journal of Chinese Pharmaceutical Sciences 2024年第4期33卷 358-362页

作者：王珣北京大学医学部药学院北京100191

2015年下半年,为贯彻落实党中央、国务院关于加快世界一流大学和一流学科建设步伐,北京大学要求各院系根据自身情况,制定适合本单位发展的人事改革方案。药学院通过对人才队伍的梳理,发现存在教授对本科生教学投入不足,缺乏成绩突出的... 详细信息

2015年下半年,为贯彻落实党中央、国务院关于加快世界一流大学和一流学科建设步伐,北京大学要求各院系根据自身情况,制定适合本单位发展的人事改革方案。药学院通过对人才队伍的梳理,发现存在教授对本科生教学投入不足,缺乏成绩突出的中青年学科带头人,课题组长准入门槛低,近亲繁殖严重等问题。之后,在院党政班子的坚定支持指导下,结合学院发展目标和现状,学院制定了《北京大学药学院人事综合改革方案》,并成为医学部率先启动人事改革的试点单位。在方案实施过程中,同时加强了对人才队伍思想政治和师德师风建设,为预聘制青年人才尽可能营造了宽松且能够全身心投入工作的科研氛围。方案实施至今,药学院“重研轻教”的现象得到扭转,更多优秀科研人才投入本科生教学;青年人才发展势头强劲,争相崭露头角;人才创新活力得到激发,科研产出效率显著提升;学科带头人与团队骨干相得益彰,中青年学科带头人不断涌现。一支规模适度、结构优化、成效显著的北大药学人才队伍正在逐步形成。

关键词：人才队伍建设人事改革药学院