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Advances in fecal microbiota transplantation for the treatment of Helicobacter pylori infection
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作者 Wei Fu yu li +3 位作者 Hai-Yan Bi Xiao-yue Wu Yan Geng Hu-lin Wang 《Infectious Diseases Research》 2026年第1期4-9,共6页
Helicobacter pylori(H.pylori)infection remains a pivotal driver of chronic gastritis,peptic ulcer,gastric mucosa-associated lymphoid tissue lymphoma and gastric cancer,yet its eradication is increasingly frustrated by... Helicobacter pylori(H.pylori)infection remains a pivotal driver of chronic gastritis,peptic ulcer,gastric mucosa-associated lymphoid tissue lymphoma and gastric cancer,yet its eradication is increasingly frustrated by climbing antibiotic resistance and intolerable side-effects of standard triple or quadruple therapies.In recent years,fecal microbiota transplantation(FMT),a strategy that reconstructs the gut ecosystem by introducing a healthy donor microbiome,has emerged as a novel adjunct or alternative.By competitively excluding H.pylori,reinforcing mucosal barrier integrity,modulating host immunity and secreting bacteriocins,FMT can raise eradication rates,relieve dyspeptic symptoms and lower recurrence.This review synthesizes up-to-date pre-clinical,pilot and controlled clinical data,dissects underlying mechanisms,compares delivery routes,donor screening protocols and safety profiles,and discusses regulatory,ethical and standardization hurdles that must be overcome before large-scale clinical application. 展开更多
关键词 fecal microbiota transplantation Helicobacter pylori gut microbiota infection treatment mechanism research
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Antidepressant effects of Peiyuan Jieyu formula in a mouse model of chronic stress in conjunction with lipopolysaccharide-induced depression 被引量:1
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作者 Qin Tang yu li +3 位作者 Tao Yang Xiaoxu Fan lina li Hongsheng Chang 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期111-119,共9页
Objective:To explore the mechanism of the Peiyuan Jieyu formula in treating depression by assessing its impact on a lipopolysaccharide-induced(LPS-induced)depression mouse model.Methods:We created a mouse model of dep... Objective:To explore the mechanism of the Peiyuan Jieyu formula in treating depression by assessing its impact on a lipopolysaccharide-induced(LPS-induced)depression mouse model.Methods:We created a mouse model of depression by exposing mice that had previously received chronic stress to intraperitoneal LPS injections.The mice were divided into the following groups:control,model,fluoxetine,Tiansi Yin,Sini powder,and low-,medium-,and high-dose Peiyuan Jieyu formula groups.Forced swim and tail suspension tests were used to assess the efficacy of the depression(despair)model,and weight gain rates were also measured.Furthermore,serum levels of various depression and inflammation-associated molecules,including tumor necrosis factor-a(TNF-a),interferon-γ(IFN-γ),tryptophan,5-hydroxytryptamine,kynurenine(KYN),and kynurenic acid(KA)were assessed.Furthermore,the expression levels of ionic calcium-binding adaptor molecule-1(IBA-1)and indoleamine 2,3-dioxygenase(IDO)mRNA in hippocampal microglia were measured.Results:The model group displayed greater despair-associated immobility,which was shortened in response to various doses of Peiyuan Jieyu formula.Furthermore,formula administration significantly reduced serum TNF-a levels and hippocampal IDO mRNA expression.The high formula dose also reduced IFN-γand IBA-1 levels,the latter was also decreased in response to the medium formula dose.However,the low formula dose reduced serum KYN level and KYN/tryptophan(TRP)and KYN/KA ratios.Conclusion:The Peiyuan Jieyu formula holds immense potential in treating depression in a mouse model,potentially inhibiting inflammation and improving TRP-KYN metabolic disorders. 展开更多
关键词 Peiyuan Jieyu formula DEPRESSION Chronic stress LIPOPOLYSACCHARIDE Inflammation Tryptophan pathway
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Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw 被引量:2
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作者 Meng-Ying liu Zhe-Hui Zhang +7 位作者 Xue-Qi Wang Qian Sun Chen Zhang yu li Zhuohua Sun Katalin Barta Feng Peng Tong-Qi yuan 《Green Energy & Environment》 SCIE EI CAS 2025年第1期161-172,共12页
Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin f... Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps process.The key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene glycol.The utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling up.In the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%. 展开更多
关键词 Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural
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高速铁路隧道紧急救援站人员安全疏散可靠性研究
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作者 王明年 郭晓晗 +3 位作者 于丽 霍建勋 张晨妍 陈昕 《铁道标准设计》 北大核心 2026年第2期114-121,共8页
为实现高速铁路隧道紧急救援站人员安全疏散可靠性分析,提升高速铁路隧道防灾疏散救援安全性,采用资料调研、理论推导等方法,首先结合既有研究成果,分析影响高速铁路隧道紧急救援站人员可用安全疏散时间(ASET)及必需安全疏散时间(RSET)... 为实现高速铁路隧道紧急救援站人员安全疏散可靠性分析,提升高速铁路隧道防灾疏散救援安全性,采用资料调研、理论推导等方法,首先结合既有研究成果,分析影响高速铁路隧道紧急救援站人员可用安全疏散时间(ASET)及必需安全疏散时间(RSET)的随机因素;在此基础上,建立高速铁路隧道紧急救援站人员疏散可靠性评估模型;结合实际工程,评估人员安全疏散可靠性。研究结果表明:紧急救援站内横通道间距、紧急救援站范围内纵坡、紧急救援站排烟口间距、火灾发展速率及总排烟量是可用安全疏散时间(ASET)计算中的随机变量;疏散人员数量及紧急救援站横通道防护门通过速率是必需安全疏散时间(RSET)计算中的随机变量;排烟模式和不排烟模式下人员在紧急救援站疏散时的可用安全疏散时间理论计算模型分别为[T]_(d1)=A^(∗)+B^(∗)α+C^(∗)α^(2)+D^(∗)Q_(p)+E^(∗)Q_(p)^(2)和[T]_(d2)=F^(∗)+G^(∗)α+H^(∗)α^(2);包含人员下车、人员在紧急救援站站台上疏散及横通道口排队疏散三阶段的必需安全疏散时间理论计算模型为[T]_(d)=N^(∗)Q_(c)+O^(∗)/(P^(∗)-Q_(c))+R^(∗)Q_(c)/N_(d);结合既有工程实例,确定若要保证几乎不发生人员安全疏散失效情况,紧急救援站排烟量应≥285 m3/s。 展开更多
关键词 高速铁路 铁路隧道 紧急救援站 人员安全疏散 可靠性分析 理论推导 数值模拟
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二维大片径Ti_(3)C_(2)T_(x)薄膜的制备及其电磁屏蔽性能
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作者 夏斌 喻莉 +5 位作者 罗志娟 王众 周娅玲 杨帆 张剑桥 程诗慧 《功能材料》 北大核心 2026年第2期109-114,共6页
二维Ti_(3)C_(2)T_(x)具有特殊的微观层状结构和良好的物理化学性能,被视为新型高效的电磁屏蔽材料。Ti_(3)C_(2)T_(x)薄膜是通过二维纳米片堆叠制备,因此单个Ti_(3)C_(2)T_(x)纳米片的性能和薄膜中片层排列的有序性都决定了Ti_(3)C_(2)... 二维Ti_(3)C_(2)T_(x)具有特殊的微观层状结构和良好的物理化学性能,被视为新型高效的电磁屏蔽材料。Ti_(3)C_(2)T_(x)薄膜是通过二维纳米片堆叠制备,因此单个Ti_(3)C_(2)T_(x)纳米片的性能和薄膜中片层排列的有序性都决定了Ti_(3)C_(2)T_(x)薄膜的电磁屏蔽性能。基于差速离心的方法,筛选并制备了二维大片径的Ti_(3)C_(2)T_(x)薄膜。利用X射线衍射仪、透射电子显微镜和扫描电子显微镜对Ti_(3)C_(2)T_(x)的化学组成、晶体结构和微观形貌进行表征,利用四探针测试仪和矢量网络分析仪研究了Ti_(3)C_(2)T_(x)的电导率和电磁屏蔽性能。结果表明,大片径Ti_(3)C_(2)T_(x)纳米片在薄膜中呈现规则有序排列,且6μm以上片径Ti_(3)C_(2)T_(x)薄膜的电导率可达1.62×10^(5)S/m,是小片径薄膜的1.5倍,其电磁屏蔽性能最高可达64.8 dB。同时,在薄膜厚度为11μm时具有4.3×10^(6)dB/m的单位厚度电磁屏蔽效能。 展开更多
关键词 二维纳米材料 Ti_(3)C_(2)T_(x) 有序排列 电磁屏蔽 导电性
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A Dynamic Knowledge Base Updating Mechanism-Based Retrieval-Augmented Generation Framework for Intelligent Question-and-Answer Systems 被引量:1
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作者 yu li 《Journal of Computer and Communications》 2025年第1期41-58,共18页
In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilizati... In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilization of this information. This study proposes a novel framework for intelligent Question-and-Answer (Q&A) systems based on Retrieval-Augmented Generation (RAG) to address these issues. The system efficiently acquires domain-specific knowledge by leveraging external databases, including Relational Databases (RDBs) and graph databases, without additional fine-tuning for Large Language Models (LLMs). Crucially, the framework integrates a Dynamic Knowledge Base Updating Mechanism (DKBUM) and a Weighted Context-Aware Similarity (WCAS) method to enhance retrieval accuracy and mitigate inherent limitations of LLMs, such as hallucinations and lack of specialization. Additionally, the proposed DKBUM dynamically adjusts knowledge weights within the database, ensuring that the most recent and relevant information is utilized, while WCAS refines the alignment between queries and knowledge items by enhanced context understanding. Experimental validation demonstrates that the system can generate timely, accurate, and context-sensitive responses, making it a robust solution for managing complex business logic in specialized industries. 展开更多
关键词 Retrieval-Augmented Generation Question-and-Answer Large Language Models Dynamic Knowledge Base Updating Mechanism Weighted Context-Aware Similarity
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Exogenous Metals Indirectly Affect Human Semen Quality via Immune Cells at Single-Cell Resolution 被引量:1
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作者 Nian liu Guangming li +14 位作者 Guohuan Zhang yu li Tian-Qing Meng Cheng-liang Xiong An Pan Hua Guo Yingying li lihong liu Bin He Yongguang Yin Jianbo Shi Yong liang Yi-Xin Wang ligang Hu Guibin Jiang 《Environment & Health》 2025年第9期1083-1093,共11页
Immune modulation is crucial for male reproduction and fertility.Metals and metalloids(metals)have been extensively studied for their immunomodulatory effects.Whether metal exposure affects semen quality through immun... Immune modulation is crucial for male reproduction and fertility.Metals and metalloids(metals)have been extensively studied for their immunomodulatory effects.Whether metal exposure affects semen quality through immune modulation is unclear.In the present study,we explored the associations between exogenous metals within immune cells,immune cell proportions,and semen quality among 84 healthy men who repeatedly provided 266 semen samples over 90 days.We employed mass cytometry(CyTOF)technology to identify immune cells in semen and measured exogenous metals in these cells at the single-cell resolution.After adjusting for potential confounders,most detected metals in immune cells were inversely associated with the proportion of immune cells in semen samples(all p<0.05),indicating the adverse effects of exogenous metals on immune cells.The proportion of immune cells showed N-shaped,nonlinear associations with sperm concentration,total count,progressive motility,and total motility.Mediation analyses showed that the percentage of indirect effects of exogenous metals on sperm quality parameters via immune cells ranged from 15.11%to 54.29%.Overall,our findings unravel the indirect effects of exogenous metal exposure on male reproductive health via immune cells,contributing valuable insights into the complex interplay between environmental factors,immune cells,and human semen quality. 展开更多
关键词 exogenous metals immune cell semen quality indirect effects SINGLE-CELL
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Shenlian Extract Protects against Ultrafine Particulate Matter-Aggravated Myocardial Ischemic Injury by Inhibiting Inflammation and Cell Apoptosis 被引量:1
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作者 Shuiqing Qu Yan liang +7 位作者 Shuoqiu Deng yu li yue Dai Chengcheng liu Tuo liu Luqi Wang lina Chen yujie li 《Biomedical and Environmental Sciences》 2025年第2期206-218,共13页
Objective Emerging evidence suggests that exposure to ultrafine particulate matter(UPM,aerodynamic diameter<0.1μm)is associated with adverse cardiovascular events.Previous studies have found that Shenlian(SL)extra... Objective Emerging evidence suggests that exposure to ultrafine particulate matter(UPM,aerodynamic diameter<0.1μm)is associated with adverse cardiovascular events.Previous studies have found that Shenlian(SL)extract possesses anti-inflammatory and antiapoptotic properties and has a promising protective effect at all stages of the atherosclerotic disease process.In this study,we aimed to investigated whether SL improves UPM-aggravated myocardial ischemic injury by inhibiting inflammation and cell apoptosis.Methods We established a mouse model of MI+UPM.Echocardiographic measurement,measurement of myocardialinfarct size,biochemical analysis,enzyme-linked immunosorbent assay(ELISA),histopathological analysis,Transferase dUTP Nick End Labeling(TUNEL),Western blotting(WB),Polymerase Chain Reaction(PCR)and so on were used to explore the anti-inflammatory and antiapoptotic effects of SL in vivo and in vitro.Results SL treatment can attenuate UPM-induced cardiac dysfunction by improving left ventricular ejection fraction,fractional shortening,and decreasing cardiac infarction area.SL significantly reduced the levels of myocardial enzymes and attenuated UPM-induced morphological alterations.Moreover,SL significantly reduced expression levels of the inflammatory cytokines IL-6,TNF-α,and MCP-1.UPM further increased the infiltration of macrophages in myocardial tissue,whereas SL intervention reversed this phenomenon.UPM also triggered myocardial apoptosis,which was markedly attenuated by SL treatment.The results of in vitro experiments revealed that SL prevented cell damage caused by exposure to UPM combined with hypoxia by reducing the expression of the inflammatory factor NF-κB and inhibiting apoptosis in H9c2 cells.Conclusion Overall,both in vivo and in vitro experiments demonstrated that SL attenuated UPMaggravated myocardial ischemic injury by inhibiting inflammation and cell apoptosis.The mechanisms were related to the downregulation of macrophages infiltrating heart tissues. 展开更多
关键词 Ultrafine particulate matter Shenlian extract INFLAMMATION Apoptosis MACROPHAGE
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不同温度循环作用下花岗岩的渗透性
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作者 余莉 赵琨 +2 位作者 周杰 李沐宸 李皓楠 《河北大学学报(自然科学版)》 北大核心 2026年第1期13-21,共9页
为探究高温循环对岩石内部结构的影响,本文开展了不同温度循环作用下花岗岩的渗透性实验,分析了经历不同温度循环处理后岩样孔隙率与渗透率的变化规律,并通过回归分析建立了纵波波速与孔隙率、渗透率之间的关系.结果表明:1)在1~3次热循... 为探究高温循环对岩石内部结构的影响,本文开展了不同温度循环作用下花岗岩的渗透性实验,分析了经历不同温度循环处理后岩样孔隙率与渗透率的变化规律,并通过回归分析建立了纵波波速与孔隙率、渗透率之间的关系.结果表明:1)在1~3次热循环中,花岗岩孔隙率与渗透率均有所降低,且变化服从对数关系;随着循环增加至5~10次,二者下降速率逐渐减缓,该特征为深部地热资源的长期开发提供了有利条件.2)不同温度循环下,花岗岩纵波波速与渗透率、孔隙率均呈现对数关系.随循环次数增加,三者关系由1~3次循环时的对数关系逐渐转变为5~10次循环时的线性关系.因此,可通过测量纵波波速来无损估算花岗岩的孔隙率与渗透率.3)对400℃热循环10次后的花岗岩进行CT扫描与SEM电镜观测发现,孔隙结构中出现碎屑颗粒,表明温度循环作用导致岩石内部结构损伤.该现象揭示了深部地热能开采过程中岩石物理性质劣化的机制,为深部地热资源开发提供了理论依据. 展开更多
关键词 花岗岩 高温循环 物理性质 渗透率 微观结构
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组态视角下提高人工智能大模型用户持续使用意愿的路径研究
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作者 于力 候娜 《科技管理研究》 2026年第3期163-172,共10页
鉴于人工智能(AI)大模型用户高渗透率与低持续性使用的突出矛盾,本研究旨在探究用户持续使用意愿的形成机制,基于技术接受模型、信息系统成功模型与计划行为理论,通过对181份问卷样本进行组态分析,揭示了影响用户持续使用意愿的多种配... 鉴于人工智能(AI)大模型用户高渗透率与低持续性使用的突出矛盾,本研究旨在探究用户持续使用意愿的形成机制,基于技术接受模型、信息系统成功模型与计划行为理论,通过对181份问卷样本进行组态分析,揭示了影响用户持续使用意愿的多种配置路径。研究发现,用户持续使用意愿的达成并非依赖单一要素,而是存在3类等效的组态路径——信息与满意度双核协同型、易用性-系统质量-满意度三角基型及效用主导下的约束突破型,其中,用户满意度被识别为最关键的驱动因素。本研究揭示了感知有用性与主观规范之间存在替代关系,进一步证明了持续使用行为的并发因果特征。这些研究成果不仅深化了对AI大模型用户行为的理解,更为大模型企业在产品设计优化、用户精细化运营和留存策略制定方面提供了有力的实践指导。 展开更多
关键词 AI大模型 持续使用意愿 组态视角 技术接受模型 信息系统成功模型 计划行为理论
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Solidworks应用于《机械设计课程设计》课程教学 被引量:10
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作者 余丽 伍哲 +1 位作者 施冠羽 郭文勇 《机械设计与制造》 北大核心 2024年第1期20-22,29,共4页
在《机械设计课程设计》课程教学中引入计算机辅助设计软件Solidworks作为辅助教学手段,通过该软件特有的运动仿真功能,建立闭式齿轮传动、锥齿轮传动、开式齿轮传动、链轮绞盘机构的虚拟模型,装配各传动机构,检查、优化设计方案,实现... 在《机械设计课程设计》课程教学中引入计算机辅助设计软件Solidworks作为辅助教学手段,通过该软件特有的运动仿真功能,建立闭式齿轮传动、锥齿轮传动、开式齿轮传动、链轮绞盘机构的虚拟模型,装配各传动机构,检查、优化设计方案,实现了传动装置的运动仿真,完成了该锚机系缆装置的模拟设计,锻炼了学生的软件使用技能,增强了学生对理论知识的深入理解和应用,激发了学生对机械课程深入学习的兴趣,提高了学生的机械设计水平,同时有助于培养学生工程实践和综合应用能力,达到了预期的教学效果。 展开更多
关键词 机械设计课程设计 SOLIDWORKS 计算机辅助设计 课程教学 虚拟仿真 装配设计
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Corrigendum to“Multi-activity ferruginated carbon quantum dots nanozyme improves wheat seedling growth and Cd tolerance”[Crop J.13(2025)510–523]
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作者 Zhiwei Lu yu li +9 位作者 Keyu Chen Songyue Chai Gehong Su Chun Wu Mengmeng Sun Yanying Wang Shiling Feng Ming Hao Hanbing Rao Dengcai liu 《The Crop Journal》 2025年第5期1654-1654,共1页
The authors regret to report some missing information in the synthetic reagents and associated changes of the paper.On page 511,the author information reads:“5.0 mmol of citric acid(C_(6)H_(8)O_(7)),5.0 mmol of ferri... The authors regret to report some missing information in the synthetic reagents and associated changes of the paper.On page 511,the author information reads:“5.0 mmol of citric acid(C_(6)H_(8)O_(7)),5.0 mmol of ferric chloride hexahydrate(FeCl_(3)·6H_(2)O),and 10.0 mmol of o-phenylenediamine(C_(6)H_(8)N_(2))were combined with 40 mL of deionized water and magnetically stirred until fully dissolved.” 展开更多
关键词 magnetically stirred synthetic reagents associated changes carbon quantum dots ferric chloride hexahydrate fecl h o multi activity deionized water ferruginated nanozyme
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A two-stage scheduling algorithm based on pointer network with attention mechanism for micro-nano Earth observation satellite constellation
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作者 Hai li yuanhao liU +5 位作者 Boyu DENG Yongjun li Xin li yu li Taijiang ZHANG Shanghong ZHAO 《Chinese Journal of Aeronautics》 2025年第8期433-448,共16页
Micro-nano Earth Observation Satellite(MEOS)constellation has the advantages of low construction cost,short revisit cycle,and high functional density,which is considered a promising solution for serving rapidly growin... Micro-nano Earth Observation Satellite(MEOS)constellation has the advantages of low construction cost,short revisit cycle,and high functional density,which is considered a promising solution for serving rapidly growing observation demands.The observation Scheduling Problem in the MEOS constellation(MEOSSP)is a challenging issue due to the large number of satellites and tasks,as well as complex observation constraints.To address the large-scale and complicated MEOSSP,we develop a Two-Stage Scheduling Algorithm based on the Pointer Network with Attention mechanism(TSSA-PNA).In TSSA-PNA,the MEOS observation scheduling is decomposed into a task allocation stage and a single-MEOS scheduling stage.In the task allocation stage,an adaptive task allocation algorithm with four problem-specific allocation operators is proposed to reallocate the unscheduled tasks to new MEOSs.Regarding the single-MEOS scheduling stage,we design a pointer network based on the encoder-decoder architecture to learn the optimal singleMEOS scheduling solution and introduce the attention mechanism into the encoder to improve the learning efficiency.The Pointer Network with Attention mechanism(PNA)can generate the single-MEOS scheduling solution quickly in an end-to-end manner.These two decomposed stages are performed iteratively to search for the solution with high profit.A greedy local search algorithm is developed to improve the profits further.The performance of the PNA and TSSA-PNA on singleMEOS and multi-MEOS scheduling problems are evaluated in the experiments.The experimental results demonstrate that PNA can obtain the approximate solution for the single-MEOS scheduling problem in a short time.Besides,the TSSA-PNA can achieve higher observation profits than the existing scheduling algorithms within the acceptable computational time for the large-scale MEOS scheduling problem. 展开更多
关键词 Micro-nano earth observation satellite Observation scheduling Large-scale scheduling Two-stage optimization Pointer network Attention mechanism
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Long lifespan Li-Se battery:Advances,challenges and prospects
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作者 Hongyan li Thomas L.Madanu +6 位作者 Tarek Barakat Wen-Da Dong Alexandru Vlad Xikun Zhang Cheng-Bin Jin yu li Bao-lian Su 《Journal of Energy Chemistry》 2025年第3期712-733,共22页
Lithium-selenium(Li-Se)batteries have attracted increasing attention as one of the next-generation battery systems due to much higher electronic conductivity and comparable volumetric capacity of Se compared to the po... Lithium-selenium(Li-Se)batteries have attracted increasing attention as one of the next-generation battery systems due to much higher electronic conductivity and comparable volumetric capacity of Se compared to the popular sulfur cathode.However,its practical application still faces great challenges,especially the rapid capacity decay triggered by the loss of active Se species.A comprehensive review to uncover the in-depth failure mechanism and provide targeted solutions to promote the stable operation of Li-Se batteries is urgently needed.This review systematically summarizes the strategies in the new perspective,focusing on the optimization of Se utilization in Li-Se batteries by keeping a high Se maintenance in the cathode and accelerating the electrochemical kinetics of lithium polyselenides(LiPSe)conversion.On the basis of stru ctural design and Li_(2)Se active material introduction to accommodate volume expansion,blocking s huttle transport of LiPSe by physical/chemical adsorption,bonding Se with polymers or cathode electrolyte interphase(CEI)construction,and catalytic design to accelerate the conversion of LiPSe,different strategies for improving the utilization of Se have been evaluated and discussed.To address the inevitable loss of Se,prospects on inactive Se reactivation and Li protection are detailedly proposed and analyzed referring to the chemistry and corrosion science.Additionally,the perspectives on the future design and comprehensive parameter evaluations for the optimization of Li-Se batteries are recommended.This review comprehensively explains the causes and solutions of capacity fading and provides potential efforts for lifespan expansion of batteries,shedding light on the future development of Li-Se batteries. 展开更多
关键词 Lithium-selenium battery Shuttle effect Adsorption Catalysis Inactive Se reactivation Li protection
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Regulating defects in single crystal perovskite by coupling Ni-Fe for high-performance anion-exchange membrane electrolyzer
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作者 yu li Gao Chen +5 位作者 Yongxin li liangshuang Fei yuxing Gu Dongliang liu Wei Zhou Zongping Shao 《Journal of Energy Chemistry》 2025年第12期452-461,I0013,共11页
Transition-metal perovskite oxides,ABO_(3±δ),are promising alternatives to precious metal catalysts for water splitting due to their tunable structures and defect engineering potential.However,polycrystalline pe... Transition-metal perovskite oxides,ABO_(3±δ),are promising alternatives to precious metal catalysts for water splitting due to their tunable structures and defect engineering potential.However,polycrystalline perovskites often show variations in composition and surface structure,complicating the identification of their underlying structure-activity relationship.In this work,we propose a surface ion-exchange strategy that finely tunes anionic and cationic defects on the surface of single-crystal BaNiO_(3),while maintaining its bulk structure and introducing surface Ni-Fe pairs.Through in situ characterization,we reveal that surface defects and Ni-Fe pairs enhance OH^(-)adsorption at both oxygen vacancies and Ni/Fe sites,facilitating a synergistic adsorbate evolution mechanism and lattice oxygen mechanism.Notably,the unique surface structure enables the faster deprotonation of intermediates and oxygen evolution reaction(OER).Thanks to the optimized surface configuration and OER mechanism,the catalyst shows excellent water oxidation performance in both rotating disk electrode and membrane electrode assembly tests. 展开更多
关键词 PEROVSKITE OER Water splitting Membrane electrode assemblies DEFECTS Oxygen vacancies
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Robust protective SiO_(x) and dual carbon layers assisted Si anode achieving rapid kinetics for ultra-fast stable Li^(+) storage
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作者 Wen-Hua Shi liang Wu +9 位作者 Zhong-Bu Qin Ya-Wen Tian Yao liu Wen-Bei yu Run-Tian Zheng Jing liu Zhi-Yi Hu yu li li-Hua Chen Bao-lian Su 《Journal of Energy Chemistry》 2025年第11期466-475,I0012,共11页
Silicon(Si)has gained popularity as a potential anodic material for Li-ion batteries(LIBs)due to its large theoretical capacity.However,low conductivity,large volume expansion,and side reactions during alloying and de... Silicon(Si)has gained popularity as a potential anodic material for Li-ion batteries(LIBs)due to its large theoretical capacity.However,low conductivity,large volume expansion,and side reactions during alloying and de-alloying lead to poor cyclic and bad high-rate performance,which has severely hindered its practical large-scale application.Herein,a novel stamen-structured Si-based anode material with a protective SiO_(x)layer and dual carbon layers(Si@SiO_(x)/C@C)is designed for high-performance LIBs.The protective SiO_(x)layer reduces side reactions and dual carbon layers enhance charge transport to improve reaction kinetics,while the unique structure provides buffering space for volume expansion.Such Si@SiO_(x)/C@C anode demonstrates impressive Li storage properties for a half-battery,including a discharge capacity of 2935 mA h g^(-1)at a current density 0.1 A g^(-1),cyclic performance(814 mA h g^(-1)at 2 A g^(-1)over 500 cycles and 988 mA h g^(-1)over 200 cycles at 1 A g^(-1))and a rate performance(609 mA h g^(-1)at 5 A g^(-1)).It also maintains a high reversible capacity of 131 mA h g^(-1)at 0.25 C after100 cycles for a full battery.This work provides insights into the novel design of multiple protective layers on Si-based anode materials for fast-charging and highly stable LIBs. 展开更多
关键词 Li-ion batteries Silicon anode Protective SiO_(x) Dual carbon layers Reaction kinetics
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Hybrid CO_(2) thermal system for post-steam heavy oil recovery:Insights from microscopic visualization experiments and molecular dynamics simulations
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作者 Ning Lu Xiaohu Dong +4 位作者 Haitao Wang Huiqing liu Zhangxin Chen yu li Deshang Zeng 《Energy Geoscience》 2025年第2期233-248,共16页
The hybrid CO_(2) thermal technique has achieved considerable success globally in extracting residual heavy oil from reserves following a long-term steam stimulation process.Using microscopic visualization experiments... The hybrid CO_(2) thermal technique has achieved considerable success globally in extracting residual heavy oil from reserves following a long-term steam stimulation process.Using microscopic visualization experiments and molecular dynamics(MD)simulations,this study investigates the microscopic enhanced oil recovery(EOR)mechanisms underlying residual oil removal using hybrid CO_(2) thermal systems.Based on the experimental models for the occurrence of heavy oil,this study evaluates the performance of hybrid CO_(2) thermal systems under various conditions using MD simulations.The results demonstrate that introducing CO_(2) molecules into heavy oil can effectively penetrate and decompose dense aggregates that are originally formed on hydrophobic surfaces.A stable miscible hybrid CO_(2) thermal system,with a high effective distribution ratio of CO_(2),proficiently reduces the interaction energies between heavy oil and rock surfaces,as well as within heavy oil.A visualization analysis of the interactions reveals that strong van der Waals(vdW)attractions occur between CO_(2) and heavy oil molecules,effectively promoting the decomposition and swelling of heavy oil.This unlocks the residual oil on the hydrophobic surfaces.Considering the impacts of temperature and CO_(2) concentration,an optimal gas-to-steam injection ratio(here,the CO_(2):steam ratio)ranging between 1:6 and 1:9 is recommended.This study examines the microscopic mechanisms underlying the hybrid CO_(2) thermal technique at a molecular scale,providing a significant theoretical guide for its expanded application in EOR. 展开更多
关键词 Heavy oil Hybrid CO_(2)thermal system Microscopic visualization experiment Molecular dynamics simulation Microscopic mechanism
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Multi-activity ferruginated carbon quantum dots nanozyme improves wheat seedling growth and Cd tolerance
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作者 Zhiwei Lu yu li +9 位作者 Keyu Chen Songyue Chai Gehong Su Chun Wu Mengmeng Sun Yanying Wang Shiling Feng Ming Hao Hanbing Rao Dengcai liu 《The Crop Journal》 2025年第2期510-523,共14页
Excessive accumulation of cadmium (Cd) impairs crop growth by inducing oxidative damage through the generation of reactive oxygen species (ROS). In this study, a biocompatible ferruginated carbon quantum dots (Fe-CQDs... Excessive accumulation of cadmium (Cd) impairs crop growth by inducing oxidative damage through the generation of reactive oxygen species (ROS). In this study, a biocompatible ferruginated carbon quantum dots (Fe-CQDs) nanozyme is developed to target ROS, thereby reducing oxidative damage and improving the absorption and transfer of Cd ions in wheat. Notably, Fe-CQDs exhibit multi-enzyme activities mimicking peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD), enabling effective neutralization of active species such as hydroxyl radicals (•OH), hydrogen peroxide (H_(2)O_(2)), and superoxide anions (O_(2)•^(-)). Importantly, root application of 10 mg L^(-1) Fe-CQDs alleviates Cd stress and promotes wheat growth in both hydroponic and soil cultures. Specifically, the levels of O_(2)•^(-), H_(2)O_(2), and malondialdehyde (MDA) in leaf tissues decrease, whereas the non-enzyme antioxidant, reduced glutathione (GSH), increases. Cell wall thickness in the Fe-CQDs-treated group is reduced by 42.4% compared with the Cd group. Moreover, Fe-CQDs enhance the expression of genes related to antioxidants, stress resistance, Cd detoxification, and nutrient transport. Transcriptomic and metabolomic analyses show that Fe-CQDs stimulate the production of flavonoids and regulate the activity of metal transporter genes (YSL, ABC, ZIP) to maintain ROS homeostasis. These findings highlight the potential of Fe-CQDs nanozyme platforms in mitigating oxidative damage and enhancing crop growth, offering new insights into the application of nanobiotechnology in agriculture. 展开更多
关键词 Fe-CQDs nanozyme Oxidative damage Wheat seedling Heavy metal stress NANOBIOTECHNOLOGY
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Enhancement of ductility and resistance to hydrogen embrittlement in laser powder-bed fusion Ti−6Al−4V alloy by reversible transformation
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作者 Huan-qi MA yu li +1 位作者 Wei li Chun XU 《Transactions of Nonferrous Metals Society of China》 2025年第12期4101-4117,共17页
To simultaneously enhance the strength−plasticity synergy and resistance to hydrogen embrittlement(HE),the post-annealing treatment was conducted in a laser powder-bed fusion Ti−6Al−4V alloy to introduce reversible tr... To simultaneously enhance the strength−plasticity synergy and resistance to hydrogen embrittlement(HE),the post-annealing treatment was conducted in a laser powder-bed fusion Ti−6Al−4V alloy to introduce reversible transformation.The microstructure,mechanical properties,and HE behavior of the alloy were analyzed by electron back-scattered diffraction,transmission electron microscopy,slow-strain-rate tensile test,hydrogen permeation and thermal desorption spectroscopy.The as-printed sample exhibited high strength but limited elongation and high HE sensitivity.When annealed at 550℃,the elongation was improved but the hydrogen diffusion rate also increased,thus promoting the formation of brittle hydride.When annealed at 750℃,the reversible transformationα'→β→α'occurred and anα'/β/α'sandwich structure formed,thereby enhancing HE resistance(reducing the total elongation loss to 12%)while maintaining high strength(~1116 MPa).The introduction of nanoscaleβ-phase and soft-orientedα'grain significantly inhibited hydride formation and hydrogen-induced crack propagation. 展开更多
关键词 Ti−6Al−4V alloy hydrogen embrittlement strength−ductility synergy POST-ANNEALING reversible transformation
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