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Dilute Aqueous-Aprotic Electrolyte Towards Robust Zn-Ion Hybrid Supercapacitor with High Operation Voltage and Long Lifespan 被引量:2
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作者 Shuilin Wu Yibing Yang +6 位作者 Mingzi Sun Tian zhang Shaozhuan Huang Daohong zhang Bolong Huang Pengfei Wang wenjun zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期1-12,共12页
With the merits of the high energy density of batteries and power density of supercapacitors,the aqueous Zn-ion hybrid supercapacitors emerge as a promising candidate for applications where both rapid energy delivery ... With the merits of the high energy density of batteries and power density of supercapacitors,the aqueous Zn-ion hybrid supercapacitors emerge as a promising candidate for applications where both rapid energy delivery and moderate energy storage are required.However,the narrow electrochemical window of aqueous electrolytes induces severe side reactions on the Zn metal anode and shortens its lifespan.It also limits the operation voltage and energy density of the Zn-ion hybrid supercapacitors.Using'water in salt'electrolytes can effectively broaden their electrochemical windows,but this is at the expense of high cost,low ionic conductivity,and narrow temperature compatibility,compromising the electrochemical performance of the Zn-ion hybrid supercapacitors.Thus,designing a new electrolyte to balance these factors towards high-performance Zn-ion hybrid supercapacitors is urgent and necessary.We developed a dilute water/acetonitrile electrolyte(0.5 m Zn(CF_(3)SO_(3))_(2)+1 m LiTFSI-H_(2)O/AN)for Zn-ion hybrid supercapacitors,which simultaneously exhibited expanded electrochemical window,decent ionic conductivity,and broad temperature compatibility.In this electrolyte,the hydration shells and hydrogen bonds are significantly modulated by the acetonitrile and TFSI-anions.As a result,a Zn-ion hybrid supercapacitor with such an electrolyte demonstrates a high operating voltage up to 2.2 V and long lifespan beyond 120,000 cycles. 展开更多
关键词 Zn-ion supercapacitors Zn metal anode Electrolyte engineering Hydrogen bonds Solvation structures
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通过调节碳自由基的反应活性调控偶联反应产物和羰基化合物的选择性合成
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作者 陈朝辉 邓军 +3 位作者 郑燕梅 张文君 董琳 陈祖鹏 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第6期135-143,共9页
在温和条件下,生物质(例如,生物质衍生醇、葡萄糖、木糖和木质素)通过光催化转化为高附加值化学品受到了广泛关注.目前,光催化氧化生物质衍生醇的主要产物是羰基化合物,即醛类化合物.相比之下,生物质衍生醇的C–C偶联产物(如氢化苯偶姻... 在温和条件下,生物质(例如,生物质衍生醇、葡萄糖、木糖和木质素)通过光催化转化为高附加值化学品受到了广泛关注.目前,光催化氧化生物质衍生醇的主要产物是羰基化合物,即醛类化合物.相比之下,生物质衍生醇的C–C偶联产物(如氢化苯偶姻和乙二醇)是制药和合成化学领域重要的中间体和原料,具有较大的应用价值.然而,由于对反应机理的理解不足,生物质衍生醇的选择性光催化氧化生成对应的C–C偶联产物和羰基化合物仍然具有挑战性.本文合成了不同金属助催化剂(Au,Pt,Pd和Ru)负载的Cd0.6Zn0.4S复合光催化剂(M-CZS)用于光催化生物质衍生醇的选择性氧化.高分辨透射电镜和X射线光电子能谱结果证明了M-CZS复合光催化剂的成功合成.紫外-可见漫反射光谱结果表明,金属Au和Ru引入后,催化剂可见光的吸收能力增强.采用光致发光光谱、时间分辨光致发光光谱、光电流强度曲线和电化学阻抗曲线研究了催化剂的载流子分离和重组行为,结果表明,金属Au和Ru的引入促进了光生载流子的分离.所制Au-CZS催化剂生成C–C偶联产物(氢化苯偶姻)的速率为40 mmol gcat.^(‒1)h^(‒1),选择性大于98%.Ru-CZS催化剂生成羰基化合物(苯甲醛)的速率为21 mmol gcat.^(‒1)h^(‒1),选择性高达99%.催化剂稳定性测试结果表明,Au-CZS和Ru-CZS催化剂具有良好的光催化稳定性.此外,所制Au-CZS和Ru-CZS催化剂对各种生物质衍生醇具有良好的光催化活性和较高的选择性.电子顺磁共振谱与中间体捕获实验结果表明,反应过程中主要的反应中间体是苯甲醇C_(α)–H键断裂产生的碳自由基中间体.通过密度泛函理论计算研究了Au-CZS和Ru-CZS光催化生物质衍生醇选择性氧化合成偶联产物和羰基化合物过程中,每一步所需的热力学自由能,结果表明,碳自由基中间体在Au和Ru的弱和强吸附,分别导致了C–C偶联产物和羰基化合物的选择性合成.综上,本文报道了一种在Cd0.6Zn0.4S固溶体中引入不同金属助催化剂的策略,通过调节相应碳自由基中间体的反应活性,实现生物质衍生醇的选择性氧化,为生物质衍生醇的高选择性转化提供了新见解. 展开更多
关键词 生物质增值 光催化 碳自由基反应性 选择性控制 吸附能
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Different ENSO Impacts on Eastern China Precipitation Patterns in Early and Late Winter Associated with Seasonally-Varying Kuroshio Anticyclonic Anomalies
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作者 Jingrui YAN wenjun zhang +1 位作者 Suqiong HU Feng JIANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1691-1703,共13页
Winter precipitation over eastern China displays remarkable interannual variability,which has been suggested to be closely related to El Niño-Southern Oscillation(ENSO).This study finds that ENSO impacts on easte... Winter precipitation over eastern China displays remarkable interannual variability,which has been suggested to be closely related to El Niño-Southern Oscillation(ENSO).This study finds that ENSO impacts on eastern China precipitation patterns exhibit obvious differences in early(November-December)and late(January-February)winter.In early winter,precipitation anomalies associated with ENSO are characterized by a monopole spatial distribution over eastern China.In contrast,the precipitation anomaly pattern in late winter remarkably changes,manifesting as a dipole spatial distribution.The noteworthy change in precipitation responses from early to late winter can be largely attributed to the seasonally varying Kuroshio anticyclonic anomalies.During the early winter of El Niño years,anticyclonic circulation anomalies appear both over the Philippine Sea and Kuroshio region,enhancing water vapor transport to the entirety of eastern China,thus contributing to more precipitation there.During the late winter of El Niño years,the anticyclone over the Philippine Sea is further strengthened,while the one over the Kuroshio dissipates,which could result in differing water vapor transport between northern and southern parts of eastern China and thus a dipole precipitation distribution.Roughly the opposite anomalies of circulation and precipitation are displayed during La Niña winters.Further analysis suggests that the seasonally-varying Kuroshio anticyclonic anomalies are possibly related to the enhancement of ENSO-related tropical central-eastern Pacific convection from early to late winter.These results have important implications for the seasonal-tointerannual predictability of winter precipitation over eastern China. 展开更多
关键词 precipitation eastern China ENSO early winter late winter Kuroshio anticyclone
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Efficient and Stable Inverted Perovskite Solar Modules Enabled by Solid-Liquid Two-Step Film Formation
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作者 Juan zhang Xiaofei Ji +13 位作者 Xiaoting Wang Liujiang zhang Leyu Bi Zhenhuang Su Xingyu Gao wenjun zhang Lei Shi Guoqing Guan Abuliti Abudula Xiaogang Hao Liyou Yang Qiang Fu Alex K.‑Y.Jen Linfeng Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期571-582,共12页
A considerable efficiency gap exists between large-area perovskite solar modules and small-area perovskite solar cells.The control of forming uniform and large-area film and perovskite crystallization is still the mai... A considerable efficiency gap exists between large-area perovskite solar modules and small-area perovskite solar cells.The control of forming uniform and large-area film and perovskite crystallization is still the main obstacle restricting the efficiency of PSMs.In this work,we adopted a solid-liquid two-step film formation technique,which involved the evaporation of a lead iodide film and blade coating of an organic ammonium halide solution to prepare perovskite films.This method possesses the advantages of integrating vapor deposition and solution methods,which could apply to substrates with different roughness and avoid using toxic solvents to achieve a more uniform,large-area perovskite film.Furthermore,modification of the NiO_(x)/perovskite buried interface and introduction of Urea additives were utilized to reduce interface recombination and regulate perovskite crystallization.As a result,a large-area perovskite film possessing larger grains,fewer pinholes,and reduced defects could be achieved.The inverted PSM with an active area of 61.56 cm^(2)(10×10 cm^(2)substrate)achieved a champion power conversion efficiency of 20.56%and significantly improved stability.This method suggests an innovative approach to resolving the uniformity issue associated with large-area film fabrication. 展开更多
关键词 Inverted perovskite solar cells Perovskite solar modules Two-step film formation CRYSTALLIZATION Defect passivation
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Achieving an ion-homogenizing and corrosion-resisting interface through nitro-coordination chemistry for stable zinc metal anodes
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作者 Jizhen Wang Long Jiao +14 位作者 Qiaoyun Liu Wei Xin Yechen Lei Tian zhang Leixin Yang Dengkun Shu Shuo Yang Kaihua Li Chenyang Li Chao Yi Hongyuan Bai Yuchao Ma Huan Li wenjun zhang Bowen'Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期10-18,共9页
Suppression of uncontrollable dendrite growth and water-induced side reactions of Zn metal anodes is crucial for achieving long-lasting cycling stability and facilitating the practical implementations of aqueous Zn-me... Suppression of uncontrollable dendrite growth and water-induced side reactions of Zn metal anodes is crucial for achieving long-lasting cycling stability and facilitating the practical implementations of aqueous Zn-metal batteries.To address these challenges,we report in this study a functional nitro-cellulose interfacial layer(NCIL)on the surface of Zn anodes enlightened by a nitro-coordination chemistry strategy.The NCIL exhibits strong zincophilicity and superior coordination capability with Zn^(2+)due to the highly electronegative and highly nucleophilic nature of the nitro functional group.This characteristic facilitates a rapid Zn-ion desolvation process and homogeneous Zn plating,effectively preventing H_(2) evolution and dendrite formation.Additionally,the negatively charged surface of NCIL acts as a shield,repelling SO_(4)^(2-)anions and inhibiting corrosive reactions on the Zn surface.Remarkably,reversible and stable Zn plating/stripping is achieved for over 5100 h at a current density of 1 mA cm^(-2),which is nearly 30 times longer than that of bare Zn anodes.Furthermore,the Zn/V_(2)O_(5) full cells with the functional interface layer deliver a high-capacity retention of 80.3%for over 10,000 cycles at 5 A g^(-1).This research offers valuable insights for the rational development of advanced protective interface layers in order to achieve ultra-long-lifeZnmetal batteries. 展开更多
关键词 Zinc metal anode Nitro-cellulose interfacial layer Coordination capability Dendrite-free deposition Long-term cycling
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Recent progress on copper catalysts with different surface states for CO_(2)electroreduction
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作者 wenjun zhang Yang Yang +1 位作者 Donggang Guo Lu Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期10-27,I0001,共19页
The electrochemical carbon dioxide reduction reaction(eCO_(2)RR),which converts CO_(2)into various hydrocarbons or alcohols,has been extensively researched because it promises a sustainable energy economy.However,only... The electrochemical carbon dioxide reduction reaction(eCO_(2)RR),which converts CO_(2)into various hydrocarbons or alcohols,has been extensively researched because it promises a sustainable energy economy.However,only copper(Cu)can currently achieve stable and efficient hydrocarbon conversion in the eCO_(2)RR.Therefore,understanding the catalytic mechanisms and summarizing the research progress on synthesis strategies of Cu catalysts are essential for the eCO_(2)RR.This paper reviews Cu catalysts with different surface states of Cu catalysts:oxide-derived Cu,Cu nanoparticles,Cu single atoms,and Cu nanoclusters.It then reviews the development and progress of different Cu-catalyst preparation methods in recent years,focusing on the activity and selectivity of materials.Besides revealing the tendencies of catalytic selection and deep reactive mechanisms of Cu catalysts with four different surface states,this review can guide the subsequent construction of catalysts and provides an understanding of catalytic mechanisms. 展开更多
关键词 eCO_(2)RR Oxide-derived Cu Cu nanoparticles Cu single atoms Cu nanoclusters
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Synergistic Impacts of Indian Ocean SST and Indo-China Peninsula Soil Moisture on the 2020 Record-breaking Mei-yu
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作者 Yinshuo DONG Haishan CHEN +2 位作者 Xuan DONG Wenjian HUA wenjun zhang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1735-1750,共16页
The Yangtze River basin(YRB)experienced a record-breaking mei-yu season in June‒July 2020.This unique long-lasting extreme event and its origin have attracted considerable attention.Previous studies have suggested tha... The Yangtze River basin(YRB)experienced a record-breaking mei-yu season in June‒July 2020.This unique long-lasting extreme event and its origin have attracted considerable attention.Previous studies have suggested that the Indian Ocean(IO)SST forcing and soil moisture anomaly over the Indochina Peninsula(ICP)were responsible for this unexpected event.However,the relative contributions of IO SST and ICP soil moisture to the 2020 mei-yu rainfall event,especially their linkage with atmospheric circulation changes,remain unclear.By using observations and numerical simulations,this study examines the synergistic impacts of IO SST and ICP soil moisture on the extreme mei-yu in 2020.Results show that the prolonged dry soil moisture led to a warmer surface over the ICP in May under strong IO SST backgrounds.The intensification of the warm condition further magnified the land thermal effects,which in turn facilitated the westward extension of the western North Pacific subtropical high(WNPSH)in June‒July.The intensified WNPSH amplified the water vapor convergence and ascending motion over the YRB,thereby contributing to the 2020 mei-yu.In contrast,the land thermal anomalies diminish during normal IO SST backgrounds due to the limited persistence of soil moisture.The roles of IO SST and ICP soil moisture are verified and quantified using the Community Earth System Model.Their synergistic impacts yield a notable 32%increase in YRB precipitation.Our findings provide evidence for the combined influences of IO SST forcing and ICP soil moisture variability on the occurrence of the 2020 super mei-yu. 展开更多
关键词 super mei-yu Indian Ocean SST soil moisture Indochina Peninsula
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初诊大肿块弥漫性大B细胞淋巴瘤患者临床特征及预后分析 被引量:3
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作者 王妍杰 张旭东 +4 位作者 葛晶晶 刘栋林 马珊珊 张文君 陈清江 《中国肿瘤临床》 CAS CSCD 北大核心 2023年第7期345-351,共7页
目的:分析初诊时伴有大肿块的弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)患者的临床特征与预后因素。方法:回顾性分析2018年1月至2021年9月郑州大学第一附属医院收治的194例大肿块DLBCL患者的临床资料,其中大肿块定义... 目的:分析初诊时伴有大肿块的弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)患者的临床特征与预后因素。方法:回顾性分析2018年1月至2021年9月郑州大学第一附属医院收治的194例大肿块DLBCL患者的临床资料,其中大肿块定义为肿瘤最大直径(maximum tumor diameter,MTD)≥7.5 cm,根据大肿块所在部位将患者分为:腹盆腔组、胸腔组、头颈部组。结果:194例大肿块DLBCL患者中位总生存(median overall survival,mOS)期为16(0~50)个月,患者1、3年总生存(overall survival,OS)率分别为75.6%、66.2%。1、3年无进展生存(progression-free survival,PFS)率分别为55.9%和44.1%。患者一线治疗后达到完全缓解(complete response,CR)、部分缓解(partial response,PR)、疾病稳定(stable disease,SD)、疾病进展(progressive disease,PD)分别为45例(23.2%)、78例(40.2%)、11例(5.7%)、60例(30.9%),一线治疗客观缓解率(overall response rate,ORR)为63.4%。单因素分析结果显示,年龄、Ann Arbor分期、β2-微球蛋白水平(β2-microglobulin,β2-MG)、有无中枢侵犯、是否放疗、大肿块所在部位是影响大肿块DLBCL患者OS的预后因素(P<0.05);Cox回归模型多因素分析结果显示,年龄>60岁、Ann Arbor分期Ⅲ/Ⅳ期、大肿块所在部位为腹盆腔组、头颈部组是大肿块DLBCL的独立不良预后因素(P<0.05)。腹盆腔组患者分期较晚、B症状多见、β2-微球蛋白水平多升高、C反应蛋白水平较高、Ki-67值较高;胸腔组年轻患者比例较高、临床分期较早、非GCB亚型更多见。腹盆腔组、胸腔组、头颈部组3组患者的3年OS率分别为60.4%、84.4%和54.2%,差异具有统计学意义(P<0.01)。结论:大肿块DLBCL患者肿瘤负荷高,一线治疗缓解率低、疾病进展率高,年龄>60岁、临床分期晚、大肿块所在腹盆腔组和头颈部组的患者预后较差。 展开更多
关键词 弥漫性大B细胞淋巴瘤 大肿块 临床特征 预后分析 肿瘤部位
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Solvent engineering towards scalable fabrication of high-quality perovskite films for efficient solar modules 被引量:4
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作者 Zhaoyi Jiang Binkai Wang +10 位作者 wenjun zhang Zhichun Yang Mengjie Li Fumeng Ren Tahir Imran Zhenxing Sun Shasha zhang Yiqiang zhang Zhiguo Zhao Zonghao Liu Wei Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期689-710,I0015,共23页
Over the last decade,remarkable progress has been made in metal halide perovskite solar cells(PSCs),which have been a focus of emerging photovoltaic techniques and show great potential for commercialization.However,th... Over the last decade,remarkable progress has been made in metal halide perovskite solar cells(PSCs),which have been a focus of emerging photovoltaic techniques and show great potential for commercialization.However,the upscaling of small-area PSCs to large-area solar modules to meet the demands of practical applications remains a significant challenge.The scalable production of high-quality perovskite films by a simple,reproducible process is crucial for resolving this issue.Furthermore,the crystallization behavior in the solution-processed fabrication of perovskite films can be strongly influenced by the physicochemical properties of the precursor inks,which are significantly affected by the employed solvents and their interactions with the solutes.Thus,a comprehensive understanding of solvent engineering for fabricating perovskite films over large areas is urgently required.In this paper,we first analyze the role of solvents in the solution-processed fabrication of large-area perovskite films based on the classical crystal nucleation and growth mechanism.Recent efforts in solvent engineering to improve the quality of perovskite films for solar modules are discussed.Finally,the basic principles and future challenges of solvent system design for scalable fabrication of high-quality perovskite films for efficient solar modules are proposed. 展开更多
关键词 Solvent engineering Scalable fabrication Perovskite film Solar cell Module
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Broad Learning System for Tackling Emerging Challenges in Face Recognition 被引量:1
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作者 wenjun zhang WenfengWang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期1597-1619,共23页
Face recognition has been rapidly developed and widely used.However,there is still considerable uncertainty in the computational intelligence based on human-centric visual understanding.Emerging challenges for face re... Face recognition has been rapidly developed and widely used.However,there is still considerable uncertainty in the computational intelligence based on human-centric visual understanding.Emerging challenges for face recognition are resulted from information loss.This study aims to tackle these challenges with a broad learning system(BLS).We integrated two models,IR3C with BLS and IR3C with a triplet loss,to control the learning process.In our experiments,we used different strategies to generate more challenging datasets and analyzed the competitiveness,sensitivity,and practicability of the proposed two models.In the model of IR3C with BLS,the recognition rates for the four challenging strategies are all 100%.In the model of IR3C with a triplet loss,the recognition rates are 94.61%,94.61%,96.95%,96.23%,respectively.The experiment results indicate that the proposed two models can achieve a good performance in tackling the considered information loss challenges from face recognition. 展开更多
关键词 Computational intelligence human-centric visual understanding
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New Continuum Observations of the Andromeda galaxy M31 with FAST
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作者 wenjun zhang Xiaohui Sun Jie Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第11期205-213,共9页
We present a new total intensity image of M31 at 1.248 GHz,observed with the Five-hundred-meter Aperture Spherical radio telescope(FAST)with an angular resolution of 4'and a sensitivity of about 16 mK.The new FAST... We present a new total intensity image of M31 at 1.248 GHz,observed with the Five-hundred-meter Aperture Spherical radio telescope(FAST)with an angular resolution of 4'and a sensitivity of about 16 mK.The new FAST image clearly reveals weak emission outside the ring due to its high sensitivity on large-scale structures.We derive a scale length of 2.7 kpc for the cosmic ray electrons and find that the cosmic ray electrons propagate mainly through diffusion by comparing the scale length at 4.8 GHz.The spectral index of the total intensity varies along the ring,which can be attributed to the variation of the spectra of synchrotron emission.This variation is likely caused by the change of star formation rates along the ring.We find that the azimuthal profile of the non-thermal emission can be interpreted by an axisymmetric large-scale magnetic field with varying pitch angle along the ring,indicating a complicated magnetic field configuration in M31. 展开更多
关键词 galaxies:ISM galaxies:magnetic fields radiation mechanisms:general (ISM:)cosmic rays
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幼儿园教师职前培养现状及其改革策略 被引量:23
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作者 张文军 管钰嫦 《学前教育研究》 CSSCI 北大核心 2019年第8期81-84,共4页
提升学前教育师资培养质量是保障学前教育事业健康发展的重要手段,幼儿园教师职前培养工作应进一步提升学生的培养层次和专业素质。针对当前幼儿园教师职前培养层次偏低、培养单位力量薄弱、教师队伍结构与质量不能满足师资培养要求、... 提升学前教育师资培养质量是保障学前教育事业健康发展的重要手段,幼儿园教师职前培养工作应进一步提升学生的培养层次和专业素质。针对当前幼儿园教师职前培养层次偏低、培养单位力量薄弱、教师队伍结构与质量不能满足师资培养要求、课程与教学体系建设滞后等问题,培养单位应进一步调整和完善人才培养结构与机制、强化师资队伍建设、深化课程与教学改革、改进人才培养评价方式,全方位提高幼儿园教师职前培养质量。 展开更多
关键词 幼儿园教师 职前培养 教师教育
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MRI and Transvaginal Ultrasound Findings of Atypical Polypoid Adenomyoma: A Case Report 被引量:6
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作者 Ya Tan Xue Hu +1 位作者 Xin Song wenjun zhang 《Chinese Medical Sciences Journal》 CAS CSCD 2022年第1期82-86,共5页
Atypical polypoid adenomyoma(APA)is an uncommon type of polypoid characterized by fibroid stroma and endometrial glands.It occurs mostly in premenopausal women and rarely in postmenopausal women with irregular vaginal... Atypical polypoid adenomyoma(APA)is an uncommon type of polypoid characterized by fibroid stroma and endometrial glands.It occurs mostly in premenopausal women and rarely in postmenopausal women with irregular vaginal bleeding.In our current case,a 76-year-old woman presented with irregular vaginal bleeding.The final pathological diagnosis of the mass was APA.APA is not easy to diagnose before surgery.On the one hand,there was no obvious particularity in imaging features and clinical features,especially for uncomfortably identifying endometrial cancer.On the other hand,APA has a pedicle,attaching to any part of the uterine cavity,which can cause pseudocoel between the mass with the uterine cavity wall.So,when it comes to getting the pathological tissue in the absence of hysteroscopy,it is easy to access to the pseudocoel and obtain endometrial tissue rather than the pathological tissue of the mass.Therefore,preoperative imaging examination is of great significance diagnosis way of thinking to clinicians for APA.In the meantime,pathological tissue of APA can be obtained by hysteroscopy in visual conditions. 展开更多
关键词 POSTMENOPAUSAL atypical polypoid adenomyoma irregular vaginal bleeding MRI transvaginal ultrasound
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Validation and application of soil moisture active passive sea surface salinity observation over the Changjiang River Estuary 被引量:3
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作者 Qiong Wu Xiaochun Wang +1 位作者 Wenhao Liang wenjun zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第4期1-8,共8页
Using sea surface salinity(SSS)observation from the soil moisture active passive(SMAP)mission,we analyzed the spatial distribution and seasonal variation of SSS around Changjiang River(Yangtze River)Estuary for the pe... Using sea surface salinity(SSS)observation from the soil moisture active passive(SMAP)mission,we analyzed the spatial distribution and seasonal variation of SSS around Changjiang River(Yangtze River)Estuary for the period of September 2015 to August 2018.First,we found that the SSS from SMAP is more accurate than soil moisture and ocean salinity(SMOS)mission observation when comparing with the in situ observations.Then,the SSS signature of the Changjiang River freshwater was analyzed using SMAP data and the river discharge data from the Datong hydrological station.The results show that the SSS around the Changjiang River Estuary is significantly lower than that of the open ocean,and shows significant seasonal variation.The minimum value of SSS appears in July and maximum SSS in December.The root mean square difference of daily SSS between SMAP observation and in situ observation is around 3 in both summer and winter,which is much lower than the annual range of SSS variation.In summer,the diffusion direction of the Changjiang River freshwater depicted by SSS from SMAP is consistent with the path of freshwater from in situ observation,suggesting that SMAP observation may be used in coastal seas in monitoring the diffusion and advection of freshwater discharge. 展开更多
关键词 soil moisture active passive mission in situ observation soil moisture and ocean salinity mission sea surface salinity Changjiang River(Yangtze River)Estuary freshwater plume
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Ultrafine Fe/Fe3C decorated on Fe-N_(x)-C as bifunctional oxygen electrocatalysts for efficient Zn-air batteries 被引量:2
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作者 Lingbo Zong Xin Chen +17 位作者 Siliang Liu Kaicai Fan Shuming Dou Jie Xu Xiaoxian Zhao wenjun zhang Yaowen zhang Weicui Wu Fenghong Lu Lixiu Cui Xiaofei Jia Qi zhang Yu Yang Jian Zhao Xia Li Yida Deng Yanan Chen Lei Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期72-79,共8页
Efficient bifunctional oxygen electrocatalysts for ORR and OER are fundamental to the development of high performance metal-air batteries.Herein,a facile cost-efficient two-step pyrolysis strategy for the fabrication ... Efficient bifunctional oxygen electrocatalysts for ORR and OER are fundamental to the development of high performance metal-air batteries.Herein,a facile cost-efficient two-step pyrolysis strategy for the fabrication of a bifunctional oxygen electrocatalyst has been proposed.The efficient non-preciousmetal-based electrocatalyst,Fe/Fe_(3)C@Fe-N_(x)-C consists of highly curved onion-like carbon shells that encapsulate Fe/Fe_(3)C nanoparticles,distributed on an extensively porous graphitic carbon aerogel.The obtained Fe/Fe_(3)C@Fe-N_(x)-C aerogel exhibited superb electrochemical activity,excellent durability,and high methanol tolerance.The experimental results indicated that the assembly of onion-like carbon shells with encapsulated Fe/Fe_(3)C yielded highly curved carbon surfaces with abundant Fe-Nxactive sites,a porous structure,and enhanced electrocatalytic activity towards ORR and OER,hence displaying promising potential for application as an air cathode in rechargeable Zn-air batteries.The constructed Zn-air battery possessed an exceptional peak power density of~147 mW cm^(-2),outstanding cycling stability(200 cycles,1 h per cycle),and a small voltage gap of 0.87 V.This study offers valuable insights regarding the construction of low-cost and highly active bifunctional oxygen electrocatalysts for efficient air batteries. 展开更多
关键词 Non-precious metal Nitrogen-rich carbon Fe/Fe_(3)C Fe-N_(x)-C Bifunctional oxygen electrocatalysts
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Molten salt assisted fabrication of Fe@Fe_(SA)-N-C oxygen electrocatalyst for high performance Zn-air battery 被引量:2
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作者 wenjun zhang Kaicai Fan +5 位作者 Cheng-Hao Chuang Porun Liu Jian Zhao Dongchen Qi Lingbo Zong Lei Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第10期612-621,I0016,共11页
Non-noble-metal-based electrocatalysts with superior oxygen reduction reaction(ORR)activity to platinum(Pt)are highly desirable but their fabrications are challenging and thus impeding their applications in metal-air ... Non-noble-metal-based electrocatalysts with superior oxygen reduction reaction(ORR)activity to platinum(Pt)are highly desirable but their fabrications are challenging and thus impeding their applications in metal-air batteries and fuel cells.Here,we report a facile molten salt assisted two-step pyrolysis strategy to construct carbon nanosheets matrix with uniformly dispersed Fe_(3) N/Fe nanoparticles and abundant nitrogen-coordinated Fe single atom moieties(Fe@Fe_(SA)-N-C).Thermal exfoliation and etching effect of molten salt contribute to the formation of carbon nanosheets with high porosity,large surface area and abundant uniformly immobilized active sites.Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)image,X-ray absorption fine spectroscopy,and X-ray photoelectron spectroscopy indicate the generation of Fe(mainly Fe_(3) N/Fe)and Fe_(SA)-N-C moieties,which account for the catalytic activity for ORR.Further study on modulating the crystal structure and composition of Fe_(3) N/Fe nanoparticles reveals that proper chemical environment of Fe in Fe_(3) N/Fe notably optimizes the ORR activity.Consequently,the presence of abundant Fe_(SA)-N-C moieties,and potential synergies of Fe_(3) N/Fe nanoparticles and carbon shells,markedly promote the reaction kinetics.The as-developed Fe@Fe_(SA)-N-C-900 electrocatalyst displays superior ORR performance with a half-wave potential(E_(1/2))of 0.83 V versus reversible hydrogen electrode(RHE)and a diffusion limited current density of 5.6 mA cm^(-2).In addition,a rechargeable Zn-air battery device assembled by the Fe@Fe_(SA)-N-C-900 possesses remarkably stable performance with a small voltage gap without obvious voltage loss after500 h of operation.The facile synthesis strategy for the high-performance composites represents another viable avenue to stable and low-cost electrocatalysts for ORR catalysis. 展开更多
关键词 Molten salt Oxygen reduction reaction Long-term durability Zn-air batteries
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The contribution of bacteria to organic matter in coal-measure source rocks 被引量:1
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作者 Qingsong Cheng Min zhang +1 位作者 Guanghui Huang wenjun zhang 《Acta Geochimica》 EI CAS CSCD 2019年第3期364-375,共12页
On the basis of GC–MS analysis, a suite of nine coal-measure source rocks(Ro 0.51%–0.63%) from the southern margin of Junggar basin was found to contain many biomarkers for bacterially-generated hydrocarbons:hopane,... On the basis of GC–MS analysis, a suite of nine coal-measure source rocks(Ro 0.51%–0.63%) from the southern margin of Junggar basin was found to contain many biomarkers for bacterially-generated hydrocarbons:hopane, sesquiterpene, C_(23)+ monomethyl alkanes(even carbon predominance), and C_(24)+ alkyl cyclohexane.Rock–eval and microscope analysis indicate that vitrinite(especially desmocollinite and homocollinite) plays a significant role in the generation of hydrocarbons in coalmeasure source rocks. Vitrinite performs this role by absorbing ultramicroscopic organic matter, generally in the form of resins or bacterial plastids. C_(23)+ monomethyl alkanes(even carbon predominance) and C_(24)+ alkyl cyclohexane series compounds are derived from bacterial metabolites of higher plants. The ultramicro organic matter adsorbed by vitrinite source rocks in the study area is probably ultramicro bacterial plastids. Because the organic matter of higher plants with low hydrogen content has been transformed into organic matter rich in hydrogen by bacteria, the hydrocarbon generation capacity of source rocks is greatly improved. In other words, in coal-measure source rocks, bacteria play an important role in hydrocarbon generation. 展开更多
关键词 Coal-measure source ROCKS Organic matter type BACTERIA Monomethyl ALKANES ALKYL CYCLOHEXANE
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Liposome cocktail activator modulates hepatocytes and remodels the microenvironment to mitigate acute liver failure 被引量:1
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作者 Na Yin wenjun zhang +4 位作者 Runxiu Wei Qiang Yang Fengming He Ling Guo Min Feng 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2022年第6期867-879,共13页
Acute liver failure(ALF)is a mortal and critical hepatic disease,in which oxidative stress,inflammation storm and hepatocyte death are crucial in the pathogenesis.Hence,in contrast to the control of a single link,a co... Acute liver failure(ALF)is a mortal and critical hepatic disease,in which oxidative stress,inflammation storm and hepatocyte death are crucial in the pathogenesis.Hence,in contrast to the control of a single link,a combination therapy targeting multiple pathogenic links of the disease will be a favorable means to control the progression of the disease.In this study,we constructed dimethyl itaconate-loaded liposomes modified with dodecyl gallate as a cocktail activator to investigate its functional role in acetaminophen(APAP)-induced ALF.Our results demonstrated that the cocktail activator acted on hepatocytes and triggered cocktail efficacy,thereby simultaneously attenuating APAP-induced hepatocyte damage and remodeling the damage microenvironment.The cocktail activator could effectively scavenge reactive oxygen species,inhibit excessive inflammatory responses and reduce cell death in impaired hepatocytes for detoxification.More importantly,the cocktail activator could remodel the damage microenvironment,thus further promoting hepatocyte expansion and specifically switching macrophages from the M1 to M2 phenotype for a favorable liver regeneration of ALF.Furthermore,in APAP-induced ALF mouse model,the cocktail activator improved liver function,alleviated histopathological damage and increased survival rate.In summary,these findings indicate that the cocktail activator may provide a promising therapeutic approach for ALF treatment as a nanomedicine. 展开更多
关键词 Cocktail activator Dimethyl itaconate Dodecyl gallate HEPATOCYTE Microenvironment modulation
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Distinctive MJO Activity during the Boreal Winter of the 2015/16 Super El Nino in Comparison with Other Super El Nino Events 被引量:1
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作者 Xuben LEI wenjun zhang +1 位作者 Pang-Chi HSU Chao LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第4期555-568,共14页
Many previous studies have demonstrated that the boreal winters of super El Nino events are usually accompanied by severely suppressed Madden-Julian oscillation(MJO) activity over the western Pacific due to strong des... Many previous studies have demonstrated that the boreal winters of super El Nino events are usually accompanied by severely suppressed Madden-Julian oscillation(MJO) activity over the western Pacific due to strong descending motion associated with a weakened Walker Circulation. However, the boreal winter of the 2015/16 super El Nino event is concurrent with enhanced MJO activity over the western Pacific despite its sea surface temperature anomaly(SSTA)magnitude over the Nino 3.4 region being comparable to the SSTA magnitudes of the two former super El Nino events(i.e.,1982/83 and 1997/98). This study suggests that the MJO enhanced over western Pacific during the 2015/16 super El Nino event is mainly related to its distinctive SSTA structure and associated background thermodynamic conditions. In comparison with the previous super El Nino events, the warming SSTA center of the 2015/16 super El Nino is located further westward, and a strong cold SSTA is not detected in the western Pacific. Accordingly, the low-level moisture and air temperature(as well as the moist static energy, MSE) tend to increase in the central-western Pacific. In contrast, the low-level moisture and MSE show negative anomalies over the western Pacific during the previous super El Nino events.As the MJO-related horizontal wind anomalies contribute to the further westward warm SST-induced positive moisture and MSE anomalies over the western tropical Pacific in the boreal winter of 2015/16, stronger moisture convergence and MSE advection are generated over the western Pacific and lead to the enhancement of MJO convection. 展开更多
关键词 super El Nino Madden-Julian oscillation moisture diagnosis
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Numerical Simulation and Moist Potential Vorticity Analysis of Torrential Rain in Jiangxi Province during June 2010 被引量:1
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作者 Zugang ZHOU Yongqiang JIANG +2 位作者 Gaoying zhang wenjun zhang Chaohui CHEN 《Asian Agricultural Research》 2014年第6期79-82,共4页
Based on the conventional ground observational data,a numerical simulation and moist potential vorticity( MPV) analysis has been carried on heavy rainfall event over Jiangxi province from 19 June to 20 June 2010,with ... Based on the conventional ground observational data,a numerical simulation and moist potential vorticity( MPV) analysis has been carried on heavy rainfall event over Jiangxi province from 19 June to 20 June 2010,with a meso-scale rainstorm model. The results show that this rare rainstorm is a typical heavy rainfall over Meiyu front. The cold air flow behind North China vortex joined up the southwestern flow located in the northwest part of the strong and stable subtropical high,thus the cold air and warm air converged and maintained over the northern part of Hunan and Jiangxi province. The simulated precipitation of the high resolution model is very similar to the observational rainfall. The model has a good predictive skill for the location,intensity and center of heavy rainfall. By moist potential vorticity analysis,it is found that the distribution characteristic of MPV which heavy rainfall happens ahead has an obvious indication for precipitation forecast. The vertical overlapping of the positive and negative MPV1 areas is favorable to the generation and development of rainstorm. This zone is also the conjoint area of convective instability and baroclinic instability. 展开更多
关键词 TORRENTIAL RAIN PRECIPITATION FORECAST NUMERICAL s
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