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以掺氢天然气为燃料直接内重整固体氧化物电池堆的稳定性
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作者 汤亚飞 武安祺 +6 位作者 韩贝贝 刘华 包善军 林王林 陈铭 官万兵 Subhash C.Singhal 《电化学(中英文)》 CAS 北大核心 2024年第1期46-54,共9页
本文研究了掺氢天然气直接内重整平管型固体氧化物电池短堆的长期稳定性和衰减机理。通过约3000小时的实测实验,结果显示,电堆的总体衰减率为2.3%·kh^(-1),电堆中三个金属连接板的面积比电阻分别增加了0.276Ω·cm^(2)、0.254... 本文研究了掺氢天然气直接内重整平管型固体氧化物电池短堆的长期稳定性和衰减机理。通过约3000小时的实测实验,结果显示,电堆的总体衰减率为2.3%·kh^(-1),电堆中三个金属连接板的面积比电阻分别增加了0.276Ω·cm^(2)、0.254Ω·cm^(2)和0.249Ω·cm^(2),但电堆中两个电池的电压反而分别增加了3.38 m V·kh^(-1)和3.78 m V·kh^(-1)。电堆衰减主要由金属连接件表层氧化及其与阴极集流层材料反应生成Sr CrO_(4)物质,两者共同作用增大了电池与金属连接体间的界面电阻所致。结果表明,以掺氢天然气为燃料直接内重整平管型固体氧化物燃料电池电堆具有良好的稳定性。本文工作为掺氢天然气在固体氧化物燃料电池堆中的直接内重整应用提供了理论参考与实验依据。 展开更多
关键词 掺氢天然气 内重整 稳定性 固体氧化物电堆
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Genome-wide association study of seedling nitrogen-use efficiency-associated traits in common wheat(Triticum aestivum L.)
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作者 Huawei Shi Weichong Wang +14 位作者 Lifeng Gao Jirong Wu chengmei Hu Huishu Yan Yugang Shi Ning Li Youzhi Ma Yongbin Zhou Zhaoshi Xu Jun chen Wensi Tang Kai chen Daizhen Sun Yuxiang Wu ming chen 《The Crop Journal》 SCIE CSCD 2024年第1期222-231,共10页
Nitrogen(N)fertilizer application is essential for crop-plant growth and development.Identifying genetic loci associated with N-use efficiency(NUE)could increase wheat yields and reduce environmental pollution caused ... Nitrogen(N)fertilizer application is essential for crop-plant growth and development.Identifying genetic loci associated with N-use efficiency(NUE)could increase wheat yields and reduce environmental pollution caused by overfertilization.We subjected a panel of 389 wheat accessions to N and chlorate(a nitrate analog)treatments to identify quantitative trait loci(QTL)controlling NUE-associated traits at the wheat seedling stage.Genotyping the panel with a 660K single-nucleotide polymorphism(SNP)array,we identified 397 SNPs associated with N-sensitivity index and chlorate inhibition rate.These SNPs were merged into 49 QTL,of which eight were multi-environment stable QTL and 27 were located near previously reported QTL.A set of 135 candidate genes near the 49 QTL included TaBOX(F-box family protein)and TaERF(ethylene-responsive transcription factor).A Tabox mutant was more sensitive to low-N stress than the wild-type plant.We developed two functional markers for Hap 1,the favorable allele of TaBOX. 展开更多
关键词 WHEAT NUE Genome-wide association study Nitrogen sensitive index Chlorate inhibition rate
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Development of D_α band symmetrical visible optical diagnostic for boundary reconstruction on EAST tokamak
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作者 陈明 沈飊 +4 位作者 Shinichiro KADO 郭笔豪 陈大龙 蔡福瑞 肖炳甲 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期44-53,共10页
To investigate the potential of utilizing visible spectral imaging for controlling the plasma boundary shape during stable operation of plasma in future tokamak, a D_α band symmetric visible light diagnostic system w... To investigate the potential of utilizing visible spectral imaging for controlling the plasma boundary shape during stable operation of plasma in future tokamak, a D_α band symmetric visible light diagnostic system was designed and implemented on the Experimental Advanced Superconducting Tokamak(EAST). This system leverages two symmetric optics for joint plasma imaging. The optical system exhibits a spatial resolution less than 2 mm at the poloidal cross-section, distortion within the field of view below 10%, and relative illumination of 91%.The high-quality images obtained enable clear observation of both the plasma boundary position and the characteristics of components within the vacuum vessel. Following system calibration and coordinate transformation, the image coordinate boundary features are mapped to the tokamak coordinate system. Utilizing this system, the plasma boundary was reconstructed, and the resulting representation showed alignment with the EFIT(Equilibrium Fitting) results. This underscores the system's superior performance in boundary reconstruction applications and provides a diagnostic foundation for boundary shape control based on visible spectral imaging. 展开更多
关键词 visible optical diagnostic plasma boundary reconstruction EAST
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跟骨钉中钉与跗骨窦入路钢板内固定治疗Sanders Ⅱ-Ⅲ型跟骨骨折的疗效分析
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作者 明晨 王承良 +1 位作者 郑凯夫 陈金武 《中国医刊》 CAS 2024年第1期60-64,共5页
目的 探讨钉中钉系统髓内固定治疗SandersⅡ-Ⅲ型跟骨骨折的临床疗效。方法 选取2020年10月至2022年10月在武汉科技大学附属华润武钢总医院住院治疗并获随访的80例SandersⅡ-Ⅲ型闭合性跟骨骨折患者,根据手术方式的不同分为髓内组(采用... 目的 探讨钉中钉系统髓内固定治疗SandersⅡ-Ⅲ型跟骨骨折的临床疗效。方法 选取2020年10月至2022年10月在武汉科技大学附属华润武钢总医院住院治疗并获随访的80例SandersⅡ-Ⅲ型闭合性跟骨骨折患者,根据手术方式的不同分为髓内组(采用钉中钉系统髓内固定治疗,40例)和钢板组(采用传统钢板内固定治疗,40例)。比较两组患者的手术情况(手术时间、术中透视次数、术中失血量、住院时间和骨折愈合时间)、影像学指标(跟骨B?hler角、Gissane角,跟骨宽度、高度和内外翻角度)、临床疗效[疼痛视觉模拟量表(VAS)评分、美国矫形外科足踝协会(AOFAS)评分、优良率]及术后并发症发生情况。结果 髓内组患者的手术时间、术中透视次数、术中失血量、住院时间和骨折愈合时间均少于钢板组,差异有统计学意义(P<0.05)。术后6个月两组患者的跟骨B?hler角、Gissane角、跟骨高度和内外翻角度较术前增加,跟骨宽度较术前降低,差异均有统计学意义(P<0.05),但以上影像学指标两组间比较差异均无统计学意义(P>0.05)。髓内组患者术后2 d的VAS评分低于钢板组,术后6个月的AOFAS评分和优良率高于钢板组,差异均有统计学意义(P<0.05)。髓内组术后并发症发生率(5.0%)低于钢板组(25.0%),差异有统计学意义(P<0.05)。结论 钉中钉系统髓内固定治疗SandersⅡ-Ⅲ型跟骨骨折可恢复根骨的解剖结构,且具有手术时间短、术中透视次数少、术中失血量少、骨折愈合时间短、术后切口并发症少等优势,值得临床应用。 展开更多
关键词 跟骨骨折 钉中钉系统髓内固定 跗骨窦入路钢板内固定
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Research on Work-Life Balance of Female Employees
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作者 ming chen 《Proceedings of Business and Economic Studies》 2024年第1期145-149,共5页
Nowadays,the pace of work and life is accelerating rapidly,accompanied by significant changes in work content and family structure.Enterprises and employees are encountering various pressures and conflicts.Female empl... Nowadays,the pace of work and life is accelerating rapidly,accompanied by significant changes in work content and family structure.Enterprises and employees are encountering various pressures and conflicts.Female employees,in particular,are experiencing increasing pressure in both social labor and family affairs,resulting in ongoing conflicts between work and life.Achieving a balance between these two domains is crucial for female employees.This article aims to analyze the influencing factors of work-life balance for female employees and to propose useful strategies to help them improve it. 展开更多
关键词 Work-life balance Work-life conflict Female employees
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妊娠高血压合并急性心肌梗死救治1例并文献复习
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作者 金智丽 曾子悦 +5 位作者 熊维 荣凌 柴玉琼 陈明 王海蓉 鲁志兵 《医学新知》 CAS 2023年第6期457-462,共6页
妊娠高血压合并急性心肌梗死的救治具有一定挑战性。本文讨论1例34岁妊娠高血压患者突发急性ST段抬高型心肌梗死(下壁)时的救治难点,提供成功救治危及该高龄孕产妇与胎儿的心血管重疾的经验与依据。本文同时检索国内外类似病例报道,冀... 妊娠高血压合并急性心肌梗死的救治具有一定挑战性。本文讨论1例34岁妊娠高血压患者突发急性ST段抬高型心肌梗死(下壁)时的救治难点,提供成功救治危及该高龄孕产妇与胎儿的心血管重疾的经验与依据。本文同时检索国内外类似病例报道,冀以探讨此类少见但风险极高的孕产妇合并心血管疾病的处理策略。 展开更多
关键词 急性心肌梗死 妊娠高血压 冠脉瘤样扩张 血栓
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An efficient microreactor with continuous serially connected micromixers for the synthesis of superparamagnetic magnetite nanoparticles 被引量:1
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作者 Wenting Fan Fang Zhao +2 位作者 ming chen Jian Li Xuhong Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第7期85-91,共7页
A new microreactor with continuous serially connected micromixers(CSCM)was tailored for the coprecipitation process to synthesize Fe_(3)O_(4) nanoparticles.Numerical simulation reveals that the two types of CSCM micro... A new microreactor with continuous serially connected micromixers(CSCM)was tailored for the coprecipitation process to synthesize Fe_(3)O_(4) nanoparticles.Numerical simulation reveals that the two types of CSCM microchannels(V-typed and U-typed)proposed in this work exhibited markedly better mixing performances than the Zigzag and capillary microchannels due to the promotion of Dean vortices.Complete mixing was achieved in the V-typed microchannel in 2.7 s at an inlet Reynolds number of 27.Fe_(3)O_(4) nanoparticles synthesized in a planar glass microreactor with the V-typed microchannel,possessing an average size of 9.3 nm and exhibiting superparamagnetism,had obviously better dispersity and uniformity and higher crystallinity than those obtained in the capillary microreactor.The new CSCM microreactor developed in this work can act as a potent device to intensify the synthesis of similar inorganic nanoparticles via multistep chemical precipitation processes. 展开更多
关键词 MICROREACTOR Continuous serially connected micromixers MIXING Nanoparticles
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COF-derived Co nanoparticles@N-doped carbon electrocatalysts for high performance Zn-air batteries
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作者 Jie Wei chengcai Zhao +4 位作者 ming chen Fengying Liu Limin Zhao Hui Zhao Zhong-Yong Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期43-50,共8页
Precise modulation of the structure and composition of electrocatalysts is critical for promoting the kinetically sluggish process of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).Covalent organic f... Precise modulation of the structure and composition of electrocatalysts is critical for promoting the kinetically sluggish process of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).Covalent organic frameworks(COF)offer a novel way to create highly efficient electrocatalysts due to their tunable composition,structure and surface area.Herein,we report a high-efficiency bifunctional electrocatalyst comprising Co nanoparticles embedded within N-doped carbons(Co@NCs)for Zn-air batteries(ZABs).The Co@NC is yielded via the coordination of a triazine COF with Co-containing precursors and subsequent calcination under inert atmosphere.The as-prepared Co@NC exhibits remarkable ORR/OER performance and great potential in rechargeable ZABs.The liquid ZAB constructed with Co@NC provides both high specific capacity and power density.Remarkably,the ZAB exhibits a voltage gap of 0.8 V during discharge and charge cycles and high stability for 220 h compared to the Pt/C-assembled battery.This strategy for regulating electrocatalytic activities of COF-derived carbon materials could be expanded for creating various carbon catalysts. 展开更多
关键词 COF Co@NC Composites ELECTROCHEMISTRY CATALYSIS Zn-air battery
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Real-world effectiveness and safety of goserelin 10.8-mg depot in Chinese patients with localized or locally advanced prostate cancer
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作者 Nanhui chen Zengjun Wang +27 位作者 ming chen Qi Ma Yi He Yujie Wang Xin Li mingxing Qiu Lei Shi Shaoxing Zhu Qun Xie Xiuheng Liu Benkang Shi Guowen Lin Weizhong Yang Yongbin Liao Haibin Zhang Shusheng Wang Jiexian Li Shaogang Wang Lijun Dong Hui chen Jiaju Lu Yongyicheng Xiaoping Zhang Lulin Ma Liqun Zhou He Wang Shen Li Dingwei Ye 《Cancer Biology & Medicine》 SCIE CAS CSCD 2023年第12期1047-1059,共13页
Objective:Real-word data on long-acting luteinizing hormone-releasing hormone(LHRH)agonists in Chinese patients with prostate cancer are limited.This study aimed to determine the real-world effectiveness and safety of... Objective:Real-word data on long-acting luteinizing hormone-releasing hormone(LHRH)agonists in Chinese patients with prostate cancer are limited.This study aimed to determine the real-world effectiveness and safety of the LHRH agonist,goserelin,particularly the long-acting 10.8-mg depot formulation,and the follow-up patterns among Chinese prostate cancer patients.Methods:This was a multicenter,prospective,observational study in hormone treatment-na?ve patients with localized or locally advanced prostate cancer who were prescribed goserelin 10.8-mg depot every 12 weeks or 3.6-mg depot every 4 weeks with or without an anti-androgen.The patients had follow-up evaluations for 26 weeks.The primary outcome was the effectiveness of goserelin in reducing serum testosterone and prostate-specific antigen(PSA)levels.The secondary outcomes included testosterone and PSA levels,attainment of chemical castration(serum testosterone<50 ng/d L),and goserelin safety.The exploratory outcome was the monitoring pattern for serum testosterone and PSA.All analyses were descriptive.Results:Between September 2017 and December 2019,a total of 294 eligible patients received≥1 dose of goserelin;287 patients(97.6%)were treated with goserelin 10.8-mg depot.At week 24±2,the changes from baseline[standard deviation(95%confidence interval)]in serum testosterone(n=99)and PSA(n=131)were-401.0 ng/d L[308.4 ng/d L(-462.5,-339.5 ng/d L)]and-35.4 ng/m L[104.4 ng/m L(-53.5,-17.4 ng/m L)],respectively.Of 112 evaluable patients,100(90.2%)achieved a serum testosterone level<50 ng/d L.Treatment-emergent adverse events(TEAEs)and severe TEAEs occurred in 37.1%and 10.2%of patients,respectively.The mean testing frequency(standard deviation)was 1.6(1.5)for testosterone and 2.2(1.6)for PSA.Conclusions:Goserelin 10.8-mg depot effectively achieved and maintained castration and was well-tolerated in Chinese patients with localized and locally advanced prostate cancer. 展开更多
关键词 GOSERELIN hormone-sensitive luteinizing hormone-releasing hormone prostate cancer China real-world
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Numerical simulation of fracturing and imbibition in shale oil horizontal wells
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作者 Rong-Li Xu Tian-Kui Guo +4 位作者 Xiao-Jia Xue Wen-Bin chen Zhan-Qing Qu ming chen Zun-Peng Hu 《Petroleum Science》 SCIE EI CSCD 2023年第5期2981-3001,共21页
The shale oil reservoir is characterized by tight lithology and ultra-low permeability,and its efficient exploitation requires the technology of multi-stage and multi-cluster hydraulic fracturing in horizontal wells a... The shale oil reservoir is characterized by tight lithology and ultra-low permeability,and its efficient exploitation requires the technology of multi-stage and multi-cluster hydraulic fracturing in horizontal wells and shut-in imbibition.After multi-stage and multi-cluster hydraulic fracturing,a complex fracture network is formed,and a large volume of frac fluid is stored within the fracture network.During shut-in,imbibition and exchange between oil and water occurs under the action of the capillary force and osmotic pressure,and the formation pressure builds up in the shale reservoir.On basis of the characteristics of shale oil reservoir,we establish a model of imbibition during fracturing injection and shut-in by coupling oilewater two-phase flow and saline ion diffusion in the hydraulic fractures(HFs)network,natural fractures(NFs)and matrix system under the action of capillary force and osmotic pressure.The DFN method and the multiple continuum method are introduced to characterize fluid flow between the HF and the NF and that between the NF and the matrix respectively,which avoids the problem of a large amount of computation of seepage within the complex fracture.Then,the discrete fracture network(DFN)model and the multiple continuum model are solved with the finite element method,and it is verified in flow field,saturation field and concentration field that the models are accurate and reliable.We propose the imbibition exchange volume for quantitative evaluation of the imbibition degree and a method of calculating the imbibition exchange volume.Simulation of oil and water flow in the fracturing and shut-in stages is performed based on these models.It is found that imbibition in the shale reservoir is driven by mechanisms of pressure difference,capillary force and osmotic pressure.The osmotic pressure and capillary force only cause an increase in the imbibition rate and a reduction in the imbibition equilibrium time and do not lead to variation in the peak of imbibition exchange volume.The imbibition equilibrium time under the action of the capillary force and osmotic pressure is reduced from 150 to 45 d compared with that under the action of the pressure difference.If imbibition equilibrium is reached,low initial water saturation,strong rock compressibility,high formation water salinity and high matrix permeability enhance imbibition and exchange of oil and water in the reservoir.The leakoff volume of frac fluid is generally larger than the imbibition exchanged volume.Leakoff equilibrium occurs slightly earlier than imbibition equilibrium.The imbibition equilibrium time is mainly affected by reservoir permeability and NF density.The number of interconnected fractures mainly affects the frac fluid volume within the hydraulic fracture in the fracturing process.The stimulated reservoir volume(SRV)mainly affects frac fluid imbibition exchange in the shut-in process. 展开更多
关键词 Shale oil Hydraulic fracturing Imbibition exchange volume Oilewater two-phase flow Shut-in time
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Study on liquid–liquid two-phase mass transfer characteristics in the microchannel with deformed insert
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作者 Qinyan Wang Yang Jin +2 位作者 Jun Li Yongbo Zhou ming chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期114-126,共13页
In this work, the liquid-liquid two-phase mass transfer characteristics in the microchannel with deformed insert were studied. The experiment used di-(2-ethylhexyl) phosphoric acid/kerosene-Cu^(2+)as the mass transfer... In this work, the liquid-liquid two-phase mass transfer characteristics in the microchannel with deformed insert were studied. The experiment used di-(2-ethylhexyl) phosphoric acid/kerosene-Cu^(2+)as the mass transfer evaluation system. The effects of some key factors such as the total flow velocity,channel inner diameter, channel length, insert diameter, extractant concentration on the extraction efficiency and mass transfer coefficient were systematically investigated. Compared with a simple microreactor, the liquid-liquid mass transfer enhancement effect of the insert was quantitatively analyzed. The study found that the regular deformation of the insert could cause fluid interface deformation and promote flow state chaos, effectively increasing the mass transfer rate. And the enhancement effect of the insert was more significant at high flow velocities. The highest mass transfer coefficient in the microchannel with deformed insert was 7.886 s^(-1), the enhancement factor could reach 4.17. And only needed 0.095 s to approach the extraction equilibrium. The deformed center insert exhibited an effective liquid-liquid mass transfer enhancement effect, which can be used as a micro-chemical process enhancement method to be applied in the fields of higher throughput mass transfer and chemical synthesis,and at the same time provide ideas for development and structural optimization of microreactors. 展开更多
关键词 MICROCHANNEL INSERT DEFORMATION Liquid–liquid extraction Mass transfer enhancement
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Numerical study on the hydrodynamics behavior of a central insert microchannel
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作者 Yongbo Zhou Yang Jin +2 位作者 Jun Li Qinyan Wang ming chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期361-373,共13页
In this work, the computational fluid dynamics method is used to study the liquid hydrodynamics behavior in the microchannel without central insert(MC1) and the central insert microchannel(MC2), respectively. The maxi... In this work, the computational fluid dynamics method is used to study the liquid hydrodynamics behavior in the microchannel without central insert(MC1) and the central insert microchannel(MC2), respectively. The maximum deviation between simulation and experiment is 24%. The formations of flow patterns are explained based on contours and force analysis where the flow pattern maps are established by two-phase flow rate. The effects of aqueous phase viscosity and two-phase flow rate on the characteristic sizes of each flow pattern are also explored. Specifically, four unconventional flow patterns are found in MC2, namely the unique droplet flow, the unique slug flow, the unique coarse annular flow and the unique film annular flow. Though the insert occupies part of the channel, the pressure difference in the channel is significantly reduced compared with MC1. Moreover, the insert significantly changes the formation velocity range of each flow pattern, greatly broadens the formation range of annular flow and also has an important influence on the characteristic size of the flow pattern. The organic-phase dimensionless axial size(Lo/W) and the dimensionless radial size(Do/W) of the droplet(slug) are negatively related to the aqueous-phase viscosity(μa) and flow rate(ua). The Do/W of the annular is negatively correlated with μaand positively correlated with organic-phase flow rate(uo). This study provides direct numerical evidence that the insert is key to the formation of bicontinuous phase flow pattern, as well as further strengthens our understanding of the flow characteristics and optimization design of insert microchannels. 展开更多
关键词 MICROCHANNEL Process intensification Computational fluid dynamics Liquid–liquid flow pattern Central insert
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杂化泛函HSE和PBE0计算CsPbI3缺陷性质的比较研究
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作者 吴晓维 张涵 +2 位作者 曾彪 明辰 孙宜阳 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2023年第9期1110-1116,I0011,I0012,共9页
在卤族钙钛矿材料的缺陷研究中,密度泛函理论计算发挥着重要作用。传统的半局域泛函(如PBE)虽然能够得到与实验接近的禁带宽度,但是已有研究表明其不能准确描述材料的带边位置。采用更准确的杂化泛函,结合自旋轨道耦合(SOC)效应与充分... 在卤族钙钛矿材料的缺陷研究中,密度泛函理论计算发挥着重要作用。传统的半局域泛函(如PBE)虽然能够得到与实验接近的禁带宽度,但是已有研究表明其不能准确描述材料的带边位置。采用更准确的杂化泛函,结合自旋轨道耦合(SOC)效应与充分的结构优化开展缺陷研究十分必要。可以选择两种杂化泛函,即屏蔽的杂化泛函HSE和非屏蔽的杂化泛函PBE0。本研究以正交相CsPbI3为例,系统比较了两种方法在缺陷性质计算上的差异。计算结果表明,对于体相性质,两种杂化泛函并无明显的差别。但是,对于缺陷性质,两种泛函出现定性的差别。HSE计算中预测的浅能级缺陷,在PBE0计算中大部分变为深能级缺陷,且缺陷转变能级和Kohn-Sham能级均出现定性差别。上述差别的本质在于,Hartree-Fock交换势具有长程作用特征,因而普通的杂化泛函如PBE0在计算量允许的超胞尺寸上无法得到收敛的结果,而HSE对上述交换势具有屏蔽作用,可采用相对小尺寸的超胞得到收敛的缺陷能级。本研究结果表明,尽管HSE杂化泛函需要较大的Hartree-Fock混合参数(约0.43),其仍是准确计算卤族钙钛矿缺陷性质的有效方法。 展开更多
关键词 钙钛矿 本征缺陷 CsPbI3 杂化泛函 第一性原理计算
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The discovery of TiO_(2)-Ⅱ,the α-PbO_(2)-structured high-pressure polymorph of rutile,in the Suizhou L6 chondrite
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作者 Xiande Xie Xiangping Gu ming chen 《Acta Geochimica》 EI CAS CSCD 2023年第1期1-8,共8页
We report the discovery of TiO_(2)-Ⅱ in the unmelted rock of the shocked Suizhou L6 chondrite.Natural TiO_(2)-Ⅱ was previously found in ultrahigh-pressure metamorphic and mantle-derived rocks,terrestrial impact stru... We report the discovery of TiO_(2)-Ⅱ in the unmelted rock of the shocked Suizhou L6 chondrite.Natural TiO_(2)-Ⅱ was previously found in ultrahigh-pressure metamorphic and mantle-derived rocks,terrestrial impact structures,and tektite.Our microscopic,Raman spectroscopic,electron microprobe and transmission electron microscopic investigations have revealed:(1) All observed TiO_(2)-Ⅱ grains are related with ilmenite and pyrophanite;(2) TiO_(2)-Ⅱ occurs as needle-and leaf-shaped inclusions in llmenite and patch-,tape-shaped body in pyrophanite;(3)The composition of TiO_(2)-Ⅱ is identical with that of its precursor rutile;(4) The Raman spectrum of TiO_(2)-Ⅱ is in good agreement with that of natural and synthesized α-PbO_(2)-type TiO_(2);(5) TiO_(2)-Ⅱ occurs mainly in the form of well-ordered nano-domains and small mis-orientation among the domains can be observed.(6) All electron diffraction reflections from TiO_(2)-Ⅱ can be indexed to α-PbO_(2)structure in space group Pbcn with lattice parameters of a=4.481 ?,b=5.578 A and c=4.921 A;(7) The exsolution inclusions of rutile from host ilmenite are mostly connected with an alternation process along the lamellar twinning plane of ilmenite induced by shockinduced high pressure and high temperature;(8) The P-T regime of 20-25 GPa and 1000 ℃ estimated for the Suizhou unmelted rock is suitable for phase transition of rutile into TiO_(2)-Ⅱ phase. 展开更多
关键词 RUTILE TiO_(2)-Ⅱ High-pressure polymorph Shock metamorphism Suizhou meteorite
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Genomic analysis of isopentenyltransferase genes and functional characterization of TaIPT8 indicates positive effects of cytokinins on drought tolerance in wheat
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作者 Na Wang Jun chen +5 位作者 Yuan Gao Yongbin Zhou ming chen Zhaoshi Xu Zhengwu Fang Youzhi Ma 《The Crop Journal》 SCIE CSCD 2023年第1期46-56,共11页
Cytokinins(CKs)function in plant development and during stress responses,but their role in drought tolerance in wheat is unknown.In the present study,24 isopentenyltransferase(IPT)genes,encoding ratelimiting enzymes i... Cytokinins(CKs)function in plant development and during stress responses,but their role in drought tolerance in wheat is unknown.In the present study,24 isopentenyltransferase(IPT)genes,encoding ratelimiting enzymes in CK biosynthesis were identified in the wheat genome.The chromosomal locations and structures of the genes,protein properties,and phylogenetic relationships were characterized.ATP/ADP TaIPT genes showed tissue-specific expression.TaIPT2,TaIPT7,and TaIPT8 expression was rapidly induced by 0.5–1 h drought treatments,which decreased to low levels after 2 h drought treatment,as did most other TaIPT genes.TaIPT8-5a/5b/5d triple mutants showed decreased levels of tZtype CK under normal and drought conditions and reduced drought tolerance,which,however,did not manifest as phenotype alterations.By contrast,transgenic wheat plants with drought-induced TaIPT8showed increased drought tolerance.Our study provides a foundation for further investigation of TaIPT genes and novel insights into the role of CKs in the drought response of wheat. 展开更多
关键词 TaIPT PHYTOHORMONE Abiotic stress Cytokinin biosynthesis WHEAT
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Liquid-liquid two-phase flow in a wire-embedded concentric microchannel: Flow pattern and mass transfer performance
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作者 ming chen Huiyan Jiao +3 位作者 Jun Li Zhibin Wang Feng He Yang Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期281-289,共9页
In this work, flow pattern and mass transfer of liquid-liquid two-phase flow in a wire-embedded concentric microchannel are studied using toluene-water system. Droplet flow, slug flow, oval flow and annular flow are o... In this work, flow pattern and mass transfer of liquid-liquid two-phase flow in a wire-embedded concentric microchannel are studied using toluene-water system. Droplet flow, slug flow, oval flow and annular flow are observed in the wire-embedded concentric microchannel. The effects of embedded wires and physical properties on flow patterns are investigated. The embedded wire insert is conducive to the formation of annular flow. The flow pattern distribution regions are distinguished by the Caaq(capillary number)±We_(org)(Weber number) flow pattern map. When Weorg<0.001, slug flow is the main flow pattern, and when Weorg>0.1, annular flow is the main flow pattern. Oval flow and droplet flow are between We_(org)= 0.001-0.1, and oval flow is transformed into droplet flow with the increase of Caaq. The effect of flow rate, phase ratio, initial acetic acid concentration, insert shape and flow patterns on mass transfers are studied. Mass transfer process is enhanced under annular flow conditions, the volumetric mass transfer coefficient is up to 0.36 s^(-1) because of the high interfacial area and interface renewal rate of annular flow. 展开更多
关键词 Flow pattern Mass transfer Microchannels Two-phase flow
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Lipoprotein(a)and Benefit of PCSK9 Inhibition in Emergency Complex Higher-risk and Indicated Patients
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作者 Zhi-li JIN Tao HE +7 位作者 Li PENG Xiao-yan WU Di FAN ming chen Yong-zhen FAN Yuan-lin GUO Zhi-bing LU Hai-rong WANG 《Current Medical Science》 SCIE CAS 2023年第6期1206-1212,共7页
Objective There is a large population of patients classified as complex higher-risk and indicated patients(CHIPs)in China with a poor prognosis.The treatment of these patients is complex and challenging,especially whe... Objective There is a large population of patients classified as complex higher-risk and indicated patients(CHIPs)in China with a poor prognosis.The treatment of these patients is complex and challenging,especially when acute cardiac events occur,such as acute coronary syndrome(ACS)or heart failure.Pharmacotherapy and some mechanical circulatory support(MCS)therapeutic devices can provide stable hemodynamic support for CHIPs-percutaneous coronary intervention(PCI).LDL-C is an important pathogenic factor in atherosclerosis,and the target of blood lipid control.Recent studies have revealed that lipoprotein(a)[Lp(a)],which is formed when a covalent bond between apolipoprotein(a)and apolipoprotein B-100 is made,produces an LDL-like particle.This particle is an independent risk factor for the development of atherosclerosis,and is closely correlated to stent thrombosis and restenosis.Furthermore,this requires active intervention.PCSK9 inhibitors have been used in lipid-lowering treatment,and preventing atherosclerosis.The present study explores the efficacy of PCSK9 inhibitors in CHIPs-ACS,and the association between the change in Lp(a)and survival after 2 years of follow-up.Methods The present real-world,prospective control study enrolled 321 CHIPs-ACS who underwent emergency PCI from August 2019 to November 2020,and these patients were followed up for 2 years.These patients were divided into two groups:PCSK9 group(n=161)given the combined PCSK9 inhibitor(140 mg of evolocumab every 2 weeks)and statins-based therapy,and SOC group(n=160)treated with statin-based lipid-lowering therapy alone.Then,the change in lipid index was measured,and the cardiovascular(CV)event recurrence rate was evaluated after one month and 2 years.Afterwards,the contribution of serum lipid parameters,especially the Lp(a)alteration,in patients with earlier initiation of the PCSK9 inhibitor to the CV outcome was analyzed.Results The LDL-C level was significantly reduced in both groups:52.3%in the PCSK9 group and 32.3%(P<0.001)in the SOC group.It is noteworthy that the Lp(a)level decreased by 13.2%in the PCSK9 group,but increased by 30.3%in the SOC group(P<0.001).Furthermore,the number of CV events was not significantly different between the PCSK9 and SOC groups after the 2-year follow-up period.In the PCSK9 group,the Lp(a)reduction was associated with the baseline Lp(a)levels of the patients(r2=−0.315,P<0.001).Moreover,the decrease in Lp(a)contributed to the decline in CV events in patients who received ACS CHIPs-PCI,and the decrease in Lp(a)level was independent of the LDL-C level reduction.Conclusion The early initiation of PCSK9 inhibitors can significantly reduce the LDL-C and Lp(a)levels in ACS CHIPs-PCI.However,further studies are needed to confirm whether PCSK9 inhibitors can reduce the incidence of CV disease in CHIPs. 展开更多
关键词 PCSK9 inhibitor complex higher-risk and indicated patients lipoprotein(a)level low-density lipoprotein cholesterol level 2-year cardiovascular event rate
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Extraction method of nanoparticles concentration distribution from magnetic particle image and its application in thermal damage of magnetic hyperthermia
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作者 汤云东 陈鸣 +1 位作者 Rodolfo C.C.Flesch 金涛 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期304-311,共8页
Magnetic particle imaging(MPI)technology can generate a real-time magnetic nanoparticle(MNP)distribution image for biological tissues,and its use can overcome the limitations imposed in magnetic hyperthermia treatment... Magnetic particle imaging(MPI)technology can generate a real-time magnetic nanoparticle(MNP)distribution image for biological tissues,and its use can overcome the limitations imposed in magnetic hyperthermia treatments by the unpredictable MNP distribution after the intratumoral injection of nanofluid.However,the MNP concentration distribution is generally difficult to be extracted from MPI images.This study proposes an approach to extract the corresponding concentration value of each pixel from an MPI image by a least squares method(LSM),which is then translated as MNP concentration distribution by an interpolation function.The resulting MPI-based concentration distribution is used to evaluate the treatment effect and the results are compared with the ones of two baseline cases under the same dose:uniform distribution and MPI-based distribution considering diffusion.Additionally,the treatment effect for all these cases is affected by the blood perfusion rate,which is also investigated deeply in this study.The results demonstrate that the proposed method can be used to effectively reconstruct the concentration distribution from MPI images,and that the weighted LSM considering a quartic polynomial for interpolation provides the best results with respect to other cases considered.Furthermore,the results show that the uniformity of MNP distribution has a positive correlation with both therapeutic temperature distribution and thermal damage degree for the same dose and a critical power dissipation value in the MNPs.The MNPs uniformity inside biological tissue can be improved by the diffusion behavior after the nanofluid injection,which can ultimately reflect as an improvement of treatment effect.In addition,the blood perfusion rate considering local temperature can have a positive effect on the treatment compared to the case which considers a constant value during magnetic hyperthermia. 展开更多
关键词 magnetic hyperthermia magnetic nanoparticles distribution thermal damage blood perfusion rate
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Uncovering the degradation mechanism induced by ion-diffusion kinetics in large-format lithium-ion pouch cells
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作者 Shi Zhou Xiaohong Zhang +4 位作者 Cong chen ming chen Fanpeng Kong Yingjie Qiao Jiajun Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期98-105,I0005,共9页
Battery electrochemistry in an actual cell is a complicated behavior influenced by the current density,uniformity,and ion-diffusion distance,etc.The anisotropism of the lithiation/delithiation degree is usually inevit... Battery electrochemistry in an actual cell is a complicated behavior influenced by the current density,uniformity,and ion-diffusion distance,etc.The anisotropism of the lithiation/delithiation degree is usually inevitable,and even worse,due to a trend of big-size cell design,typically such as 4680 and blade cells,which accelerated a battery failure during repeat lithiation and delithiation of cathodes.Inspire by that,two big-size pouch cells with big sizes,herein,are selected to reveal the ion-diffusion dependency of the cathodes at different locations.Interestingly,we find that the LiCoO_(2) pouch cell exhibits ~5 A h loss after 120 charge-discharge cycles,but a 15 A h loss is verified in a LiNixMnyCO_(1-x)-yO_(2)(NCM) cell.Synchrotron-based imaging analysis indicates that higher ion-diffusion rates in the LiCoO_(2)than that in the LiNixMnyCO_(1-x)-yO_(2)is the determined factor for the anisotropic cathode fading,which is responsible for a severe mechanical issue of particle damage,such as cracks and even pulverization,in the cathode materials.Meanwhile,we verify the different locations at the near-tab and bottom of the electrode make it worse due to the ion-diffusion kinetics and temperature,inducing a spatially uneven electrochemistry in the big-size pouch cell.The findings give an in-depth insight into pouch cell failure and make a guideline for high-energy cell design and development. 展开更多
关键词 Ah-level lithium-ion pouch cells Cathode materials lon-diffusion kinetics X-ray tomography
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Influence of Dowel Center Spacing on Chamfered-Joint Components Made byCupressus funebris Wood
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作者 Jianhua Lyu Jialei Wang +1 位作者 Ziqiang chen ming chen 《Journal of Renewable Materials》 SCIE EI 2023年第1期309-319,共11页
The traditional tenon and mortise joint has low processing efficiency and a weak theoretical basis,making the structure easy to deform and damage,reducing the safety,and increasing waste of resources.This study aims t... The traditional tenon and mortise joint has low processing efficiency and a weak theoretical basis,making the structure easy to deform and damage,reducing the safety,and increasing waste of resources.This study aims to determine the optimum dowel center spacing parameter for chamfered-joint components and the maximum value of the strength of joints loaded into bending strength and tensile strength.In this study,an integrated opti-mization method combining the single-factor test and one-way ANOVA analysis was proposed to study the influ-ence of the dowel center spacing on the bending strength and the tensile strength of chamfered-joint components made by Cupressus funebris wood.The results revealed that the bending strength of chamfered-joint components decreases linearly with the increase of the dowel center spacing.In addition,the tensile strength of chamfered-joint components increases first and then decreases with the increase of the dowel center spacing,showing para-bola change.The relational expression between dowel center spacing,the bending strength,dowel center spacing and the tensile strength were obtained. 展开更多
关键词 Dowel center spacing chamfered-joint bending strength tensile strength Cupressus funebris wood
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