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Characteristics of Submicron Aerosols (PM_(1)) in a Yangtze River Delta Megacity:Composition,Sources,and Light Absorption
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作者 Shiyue YANG Haifeng MENG +8 位作者 Ning ZHANG Shijie CUI Yuanjie SHAN Yu HUANG Yunlong XU Chongchong ZHANG Xinlei GE Mindong CHEN junfeng wang 《Advances in Atmospheric Sciences》 2026年第1期247-258,共12页
We conducted a field campaign to investigate the chemical composition,sources,and light absorption of submicron aerosols(PM_(1))from early 2022 in Nanjing,China.The average concentration of PM_(1) was 31μg m^(−3),org... We conducted a field campaign to investigate the chemical composition,sources,and light absorption of submicron aerosols(PM_(1))from early 2022 in Nanjing,China.The average concentration of PM_(1) was 31μg m^(−3),organics(33%)constituted the largest fraction,followed by nitrate(30%),sulfate(18%),ammonium(15%),chloride(3%),and rBC(2%).Four organic aerosol(OA)subcomponents were identified,including two primary OA(POA)and two secondary OA(SOA).The less-oxidized SOA(LO-OOA)contributes the most to the total OA mass(59%).LO-OOA is tightly correlated with the tracer ion C_(2)H_(4)O_(2)^(+)from levoglucosan,and another aged biomass-burning derived species,K_(3)SO_(4)^(+),suggesting it was likely influenced by aged biomass-burning OA.Our study also revealed that fireworks during the Spring Festival have a detrimental impact on air quality,contributing to secondary formation and accumulation under static winter meteorological conditions,prolonging the pollution duration.Also,LO-OOA was found to have the strongest light-absorbing ability.Our results highlight that the light absorption of LO-OOA can mainly be attributed to the C_(x)H_(y)N^(+) family,increased with the double-bond equivalent value.The more-oxidized SOA(MO-OOA)exhibited a negligible light absorption and was strongly correlated with daytime photochemical processes,implying a light-bleaching effect.This study enhances our understanding of the regional contribution of biomass combustion and fireworks to PM_(1) pollution in Nanjing,a typical megacity in the Yangtze River Delta region,during winter,aiding in the development of strategies for long-term air quality improvement in the region. 展开更多
关键词 PM_(1) source apportionment Yangtze River Delta Region brown carbon
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Chemical characteristics and sources apportionment of volatile organic compounds in the primary urban area of Shijiazhuang,North China Plain 被引量:2
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作者 Xiao Zhang junfeng wang +8 位作者 Jiangwei Zhao Junliang He Yali Lei Kai Meng RuiWei Xue Zhang Miaomiao Zhang Shuangying Ni Eleonora Aruffo 《Journal of Environmental Sciences》 2025年第3期465-475,共11页
VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effe... VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effective implementation of measures aimed at preventing and controlling atmospheric pollution.FromJuly to October 2020,onlinemonitoringwas conducted in the main urban area of Shijiazhuang to collect data on VOCs and analyze their concentrations and reactivity.Additionally,the PMF(positive matrix factorization)method was utilized to identify the VOCs sources.Results indicated that the TVOCs(total VOCs)concentration was(96.7±63.4μg/m^3),with alkanes exhibiting the highest concentration of(36.1±26.4μg/m^3),followed by OVOCs(16.4±14.4μg/m^3).The key active components were alkenes and aromatics,among which xylene,propylene,toluene,propionaldehyde,acetaldehyde,ethylene,and styrene played crucial roles as reactive species.The sources derived from PMF analysis encompassed vehicle emissions,solvent and coating sources,combustion sources,industrial emissions sources,as well as plant sources,the contribution of which were 37.80%,27.93%,16.57%,15.24%,and 2.46%,respectively.Hence,reducing vehicular exhaust emissions and encouraging neighboring industries to adopt low-volatile organic solvents and coatings should be prioritized to mitigate VOCs levels. 展开更多
关键词 Volatile organic compounds Pollution characteristics Ozone formation potential OH radical loss rate Source apportionment
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炼化反渗透浓水中有机物处理技术 被引量:4
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作者 王均凤 王毅霖 +5 位作者 张晓飞 王道广 李亚辉 何宏艳 李兴春 张锁江 《化学进展》 SCIE CAS CSCD 北大核心 2020年第10期1462-1481,共20页
双膜工艺作为一种有效的废水处理方法,已被炼化企业广泛采用。然而,该工艺在使用过程中会产生一定量的含有机物高盐反渗透浓水(ROCs)。在国家排放标准对废水外排指标日趋严格的情况下,反渗透浓水直接外排已被禁止。因此,含有机物高盐反... 双膜工艺作为一种有效的废水处理方法,已被炼化企业广泛采用。然而,该工艺在使用过程中会产生一定量的含有机物高盐反渗透浓水(ROCs)。在国家排放标准对废水外排指标日趋严格的情况下,反渗透浓水直接外排已被禁止。因此,含有机物高盐反渗透浓水处理技术成为研究的热点。本文对炼化反渗透浓水处理技术研究进展进行综述和讨论。首先本文对不同炼化企业反渗透浓水的组成进行了汇总和分析;其次,对反渗透浓水中有机物的去除技术,如物理化学方法、高级氧化法和生化方法等,进行了详细讨论,并深入分析了新兴高级氧化工艺的机理和优缺点;最后对炼化反渗透浓水中盐回收技术进行了讨论。 展开更多
关键词 双膜工艺 反渗透浓水 盐回收 氧化工艺 有机污染物
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The relationship between OPLL and metabolic disorders
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作者 junfeng wang Ziheng Wei +4 位作者 Qingjie Kong Yanqing Sun Zhichao Zhang Haiyuan Yang Xiongsheng Chen 《Bone Research》 2025年第6期1342-1352,共11页
Ossification of the posterior longitudinal ligament(OPLL)is a degenerative disease characterized by progressive ectopic bone formation process,which can lead to severe neurological impairments and reduced quality of l... Ossification of the posterior longitudinal ligament(OPLL)is a degenerative disease characterized by progressive ectopic bone formation process,which can lead to severe neurological impairments and reduced quality of life.While the etiology of OPLL is generally considered multifactorial,there is no consensus regarding these contributing factors including genetic,endocrine,biomechanical,immune and lifestyle factors.Through accumulating evidence from multidisciplinary investigations,the pathophysiological connection between OPLL and endocrine-metabolic dysregulation is becoming increasingly clear.Nevertheless,comprehensive understanding of the relationship between the two is hindered by several problems,such as methodological limitations and inadequate mechanistic studies.This review takes a deep dive into the possible factors contributing to OPLL from all aspects of metabolism,including glucose metabolism,lipid metabolism,bone and mineral metabolism,leptin,vitamin,growth hormone/IGF-1 and sex hormones,highlighting their potential roles in the onset and progression of OPLL.Clarifying the etiology of OPLL and elucidating the underlying pathogenesis are crucial for advancing both early intervention strategies and therapeutic approaches in clinical management.Therefore,the endocrine and metabolic disorders in OPLL patients should become a focus of future research. 展开更多
关键词 ossification posterior longitudinal ligament opll progressive ectopic bone formation processwhich glucose metabolism multidisciplinary investigationsthe pathophysiological connec endocrine metabolic dysregulation lipid metabolism degenerative disease
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Analysis of atmospheric pollutant characteristics and regional transport in coastal area along the East China Sea
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作者 Yangzhou Wu Dantong Liu +5 位作者 Honghui Xu Meng Shan Siyuan Li Ping Tian Kang Hu junfeng wang 《Journal of Environmental Sciences》 2025年第10期225-238,共14页
PM_(2.5) and black carbon(BC)are important air pollutants impacting radiation balance,air quality,health,and ecosystems.Ozone(O_(3))levels are increasing despite decreases in other pollutants,posing a challenge for po... PM_(2.5) and black carbon(BC)are important air pollutants impacting radiation balance,air quality,health,and ecosystems.Ozone(O_(3))levels are increasing despite decreases in other pollutants,posing a challenge for pollution control,especially in coastal cities like Zhoushan,where the monsoonal climate can exacerbate PM_(2.5) and ozone pollution.This study conducted continuous online measurements of major atmospheric pollutants in Zhoushan,Zhejiang Province,in 2020.The results indicate that the highest contribution from local air masses in Zhoushan is observed in spring,accounting for 17.7%,while the greatest average contribution from northern Zhejiang Province,Jiangsu Province,and Shanghai occurs in winter,at 18.5%.Pollutant concentrationswere seasonally variable,with PM_(2.5),BC,and sulfur dioxide concentrations 56.6%,36%,and 58.2%higher in the cold season compared to the warm season.The O_(3) in spring is approximately 50%higher than that in summer.Ship emissions significantly contributed to BC,nitrogen oxides(NO_(x)),and carbon monoxide in Zhoushan.In spring,PM_(2.5) sources included photochemical processes and northern air mass transport,while in winter,PM_(2.5) was due to regional transport.The inhibitory effect of PM_(2.5) on O_(3) formation in the Zhoushan area is relatively weak.Reducing NO_(x) emissions may increase O_(3),emphasizing the need for volatile organic compounds monitoring and regional control measures to improve air quality and ensure sustainable development in Zhoushan. 展开更多
关键词 Coastal city PM_(2.5) OZONE Black carbon Ship emission Seasonal variation
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Biophysical and NMR analysis reveals binding affinity between HAX1 and CLPB proteins
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作者 Huiqin Zhang Yong Liu +4 位作者 Yunyan Li Maosen Ruan Shu Zhou junfeng wang Jing Yang 《Magnetic Resonance Letters》 2025年第1期12-21,共10页
HCLS1-associated protein X-1(HAX1)is a multifunctional mitochondrial protein involved in the regulation of apoptosis,a crucial process of programmed cell death,and mRNA processing.Despite its significance,limited stru... HCLS1-associated protein X-1(HAX1)is a multifunctional mitochondrial protein involved in the regulation of apoptosis,a crucial process of programmed cell death,and mRNA processing.Despite its significance,limited structural data is available for HAX1,hindering a comprehensive understanding of its biological function.Notably,the caseinolytic mitochondrial matrix peptidase chaperone subunit B(CLPB)has been identified as an interacting partner of HAX1,yet the biophysical properties and binding affinity governing their interaction remain poorly defined.In this study,we present a thorough biophysical characterization of full-length human HAX1 and CLPB,accomplished through recombinant expression and purification.By employing size exclusion chromatography,dynamic light scattering,and circular dichroism spectroscopy,we successfully established their biophysical properties,revealing contrasting structural features,with CLPB displaying a-helical content and HAX1 exhibiting a disordered nature.Moreover,we employed solutionstate nuclear magnetic resonance(NMR)spectroscopy to probe their binding affinity.Our findings demonstrate the formation of stable multimeric complexes between HAX1 and CLPB,and we quantified a dissociation constant in the low range of micro-molar for their high affinity interaction.These results lay the foundation for further in-depth investigations into the dynamics and energetics governing the HAX1-CLPB interaction,ultimately contributing to a comprehensive understanding of their functional mechanisms. 展开更多
关键词 HAX1 CLPB Protein interaction Biophysical characterization NMR spectroscopy
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Tailoring cryogenic thermal conductivity in EuTiO_(3)-based magnetic refrigeration materials
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作者 Huicai Xie Jiaxin Jiang +5 位作者 Hao Sun Zhenxing Li Jun Liu junfeng wang Zhaojun Mo Jun Shen 《Journal of Rare Earths》 2025年第5期997-1002,共6页
As one of the core components of a magnetic refrigerator,magnetic refrigeration materials are expected to have not only a considerable magnetocaloric effect but also excellent thermal conductivity.The poor thermal con... As one of the core components of a magnetic refrigerator,magnetic refrigeration materials are expected to have not only a considerable magnetocaloric effect but also excellent thermal conductivity.The poor thermal conductivity of many competitive oxide-based magnetic refrigerants,exemplified by EuTiO3-based compounds,acts as a major limitation to their practical application.Therefore,improving the thermal conductivity of magnetic refrigeration materials has become a research emphasis of magnetic refrigeration in recent years.In this work,a series of EuTiO_(3)(ETO)/Cu composites with different copper additives was prepared using a solid-phase reaction method by introducing appropriate amounts of copper powder.The influence of the introduction of copper on the phase composition,microstructure,thermal conductivity,and magnetocaloric effect of the composites was systematically investigated.Unexpectedly,the thermal conductivity of the composites is enhanced by up to 260%due to copper addition,accompanied by only a 5%decrease in magnetic entropy change and refrigerating capacity.Copper additive forms localized thermal conductive networks and promotes the densification process,resulting in significantly enhanced thermal conductivity of the composites.This work demonstrates the feasibility of improving the thermal conductivity of oxide-base d magnetic refrigeration materials by introducing highly thermally conductive substances. 展开更多
关键词 Thermal conductivity EuTiO_(3) Magnetic refrigeration Rare earths Thermal conductive network
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Efficient synthesis of nano high-entropy compounds for advanced oxygen evolution reaction
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作者 Genxiang wang Linfeng Fan +3 位作者 Peng wang junfeng wang Fen Qiao Zhenhai Wen 《Chinese Chemical Letters》 2025年第4期216-220,共5页
Developing efficient electrocatalysts for oxygen evolution reaction(OER)is imperative to enhance the overall efficiency of electrolysis systems and rechargeable metal-air batteries operating in aqueous solutions.High-... Developing efficient electrocatalysts for oxygen evolution reaction(OER)is imperative to enhance the overall efficiency of electrolysis systems and rechargeable metal-air batteries operating in aqueous solutions.High-entropy materials,featured with their distinctive multi-component properties,have found extensive application as catalysts in electrochemical energy storage and conversion devices.However,synthesizing nanostructured high-entropy compounds under mild conditions poses a significant challenge due to the difficulty in overcoming the immiscibility of multiple metallic constituents.In this context,the current study focuses on the synthesis of an array of nano-sized high entropy sulfides tailored for OER via a facile precursor pyrolysis method at low temperature.The representative compound,Fe Co Ni Cu Mn Sx,demonstrates remarkable OER performance,achieving a current density of 10 m A/cm^(2) at an overpotential of merely 220 m V and excellent stability with constant electrolysis at 100 m A/cm^(2) for over 400 h.The in-situ formed metal(oxy)hydroxide has been confirmed as the real active sites and its exceptional performance can be primarily attributed to the synergistic effects arising from its multiple components.Furthermore,the synthetic methodology presented here is versatile and can be extended to the preparation of high entropy phosphides,which also present favorable OER performance.This research not only introduces promising non-noble electrocatalysts for OER but also offers a facile approach to expand the family of nano high-entropy materials,contributing significantly to the field of electrochemical energy conversion. 展开更多
关键词 High-entropy sulfides High-entropy phosphides Oxygen evolution reaction Efficient synthesis Nano structure
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Giant low-field magnetocaloric effect in unstable antiferromagnetic Tm_(1-x)Er_(x)Ni_(2)Si_(2)(x=0.2,0.4)compounds
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作者 Bo Xu Lu Tian +4 位作者 junfeng wang Mei Wu Xinqiang Gao Zhenxing Li Jun Shen 《Journal of Rare Earths》 2025年第2期312-318,I0003,共8页
Magnetic refrigeration(MR)technology is regarded as an ideal solution for cryogenic applications,relying on magnetocaloric materials which provide necessary chilling effect.A series of polycrystalline Tm_(1-x)Er_(x)Ni... Magnetic refrigeration(MR)technology is regarded as an ideal solution for cryogenic applications,relying on magnetocaloric materials which provide necessary chilling effect.A series of polycrystalline Tm_(1-x)Er_(x)Ni_(2)Si_(2)(x=0.2,0.4)compounds was synthesized,and their magnetic properties,magnetic phase transition together with magnetocaloric effect(MCE)were studied.The Tm_(1-x)Er_(x)Ni_(2)Si_(2)(x=0.2,0.4)compounds display a field-induced metamagnetic transition from antiferromagnetic(AFM)to ferromagnetism(FM)in excess of 0.2 T,respectively.Meanwhile,the AFM ground state is unstable.Under the field change of 0-2 T,the values of maximal magnetic entropy change(-ΔS_(M)^(max))and refrigerant capacity(RC)for Tm_(0.8)Er_(0.2)Ni_(2)Si_(2)compound are 17.9 J/(kg·K)and 83.5 J/kg,respectively.The large reversible MCE under low magnetic fields(≤2 T)indicates that Tm_(0.8)Er_(0.2)Ni_(2)Si_(2)compound can serve as potential candidate materials for cryogenic magnetic refrigeration. 展开更多
关键词 Magnetocaloric materials Magnetocaloric effects Cryogenic magnetic refrigeration TmNi_(2)Si_(2) Rare earths
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Transmembrane association of DDR1 and DDR2 mediated by Leucine zipper motifs
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作者 Feiyu Huang Yuzhe Li +4 位作者 Peng Zhang Jinqian Li Can Xie junfeng wang Tiantian Cai 《Magnetic Resonance Letters》 2025年第4期59-71,共13页
Discoidin domain receptors(DDRs)are single-pass transmembrane proteins belonging to receptor tyrosine kinases(RTKs)family,which are activated by collagen ligands with unusual slow,sustained kinetics,distinguishing the... Discoidin domain receptors(DDRs)are single-pass transmembrane proteins belonging to receptor tyrosine kinases(RTKs)family,which are activated by collagen ligands with unusual slow,sustained kinetics,distinguishing them from canonical RTKs.While DDRs play critical roles in cell adhesion,differentiation,and cancer progression,their activation mechanisms remain partly understood.Here,we investigated the transmembrane domains(TMDs)of DDR1 and DDR2 to elucidate their interaction dynamics in membrane.Using bacterial adenylate cyclase two-hybrid(BACTH)assays,we demonstrated robust homotypic interactions and even stronger heterotypic associations between DDRTMDs.NMR spectroscopy of DDR1TMD and DDR2TMD reconstituted in lipid bilayer-mimetic bicelles showed obvious chemical shift alterations,further validating the stability of their heterocomplex formation.Systematic mutagenesis identified leucine zipper motifs rather than GXXXA motifs mediated both homo-and hetero-associations of DDR1TMD and DDR2TMD.These findings demonstrated the TMD as a critical mediator of DDRs oligomerization and revealed their interaction patterns within membrane.Our study advances the understanding of DDR signaling regulation and highlights transmembrane domain interactions as potential targets for modulating DDR-related pathologies. 展开更多
关键词 Discoidin domain receptor(DDR) Transmembrane domain(TMD) Leucine zipper motif NMR
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Prognostic models for lung cancer in smokers and nonsmokers:an updated systematic review and meta-analysis
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作者 Xinyue Pan Boxing Feng +4 位作者 Ying Chen junfeng wang Xuanqi Pan Taihing Lam Jing Pan 《Oncology and Translational Medicine》 2025年第3期112-117,共6页
Background:Lung cancer is the leading cause of cancer-related mortality,and while low-dose computed tomography screening may reduce mortality,emerging prognostic models show superior discriminative efficacy compared t... Background:Lung cancer is the leading cause of cancer-related mortality,and while low-dose computed tomography screening may reduce mortality,emerging prognostic models show superior discriminative efficacy compared to age-and smoking history-based screening.However,further research is needed to assess their reliability in predicting lung cancer risk in high-risk patients.Methods:This study evaluated the predictive performance and quality of existing lung cancer prognostic models through a systematic review and meta-analysis.A comprehensive search was conducted in PubMed,Cochrane,Web of Science,CNKI,and Wanfang for articles published between January 1,2000,and February 13,2025,identifying population-basedmodels incorporating all available modeling data.Results:Among 72 analyzed studies,models were developed from Asian(28 studies,including 23 Chinese cohorts)and European/American(48 studies)populations,with only 6 focusing on nonsmokers.Twenty-one models included genetic markers,15 used clinical factors,and 40 integrated epidemiological predictors.Although 37 models underwent external validation,only 4 demonstrated minimal bias and clinical applicability.A meta-analysis of 11 repeatedly validated models revealed calibration and discrimination,though some lacked calibration data.Conclusions:Few lung cancer prognostic models exist for nonsmokers.Most models exhibit poor predictive performance in external validations,with significant bias and limited application scope.Widespread external validation,standardized model development,and reporting techniques are needed to accurately identify high-risk individuals and ensure applicability across diverse populations. 展开更多
关键词 Lung cancer Prognostic model SCREEN Risk factor
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Boosting Sensitivity of Cellulose Pressure Sensor via Hierarchically Porous Structure
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作者 Minzhang Chen Xiaoni An +4 位作者 Fengyan Zhao Pan Chen junfeng wang Miaoqian Zhang Ang Lu 《Nano-Micro Letters》 2025年第9期59-74,共16页
Pressure sensors are essential for a wide range of applica-tions,including health monitoring,industrial diagnostics,etc.However,achieving both high sensitivity and mechanical ability to withstand high pressure in a si... Pressure sensors are essential for a wide range of applica-tions,including health monitoring,industrial diagnostics,etc.However,achieving both high sensitivity and mechanical ability to withstand high pressure in a single material remains a significant challenge.This study introduces a high-performance cellulose hydrogel inspired by the biomi-metic layered porous structure of human skin.The hydrogel features a novel design composed of a soft layer with large macropores and a hard layer with small micropores,each of which contribute uniquely to its pressure-sensing capabilities.The macropores in the soft part facilitate significant deforma-tion and charge accumulation,providing exceptional sensitivity to low pressures.In contrast,the microporous structure in the hard part enhances pressure range,ensuring support under high pressures and preventing structural failure.The performance of hydrogel is further optimized through ion introduction,which improves its conductivity,and as well the sensitivity.The sensor demonstrated a high sensitivity of 1622kPa^(-1),a detec-tion range up to 160 kPa,excellent conductivity of 4.01 Sm^(-1),rapid response time of 33 ms,and a low detection limit of 1.6 Pa,outperforming most existing cellulose-based sensors.This innovative hierarchically porous architecture not only enhances the pressure-sensing performance but also offers a simple and effective approach for utilizing natural polymers in sensing technologies.The cellulose hydrogel demonstrates sig-nificant potential in both health monitoring and industrial applications,providing a sensitive,durable,and versatile solution for pressure sensing. 展开更多
关键词 Pressure sensor CELLULOSE HYDROGEL High sensitivity
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超临界二氧化碳布雷顿循环热力学优化研究 被引量:1
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作者 王俊峰 黄彦平 +1 位作者 臧金光 刘光旭 《核科学与技术》 2020年第2期53-60,共8页
超临界二氧化碳布雷顿循环是核能技术创新的重要选择。基于热力学第一定律,开展了超临界二氧化碳布雷顿循环热力学分析与优化研究。为进一步提高转换效率,提出了双级分流压缩循环方案,开展了热力学特性分析和评价,获得了间冷、再热对系... 超临界二氧化碳布雷顿循环是核能技术创新的重要选择。基于热力学第一定律,开展了超临界二氧化碳布雷顿循环热力学分析与优化研究。为进一步提高转换效率,提出了双级分流压缩循环方案,开展了热力学特性分析和评价,获得了间冷、再热对系统效率的影响规律,并与传统再压缩循环进行了定量比较。研究表明:本文提出的双级分流压缩循环比传统再压缩循环的热效率可提高1~2个百分点,带间冷和再热时热效率可提高近3个百分点。 展开更多
关键词 超临界二氧化碳 布雷顿循环 热力学优化
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周易视角探究未病之糖尿病
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作者 包额尔敦朝克图 王俊峰 《中国蒙医药(蒙)》 2025年第1期5-9,共5页
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Cloning and expression of the first gene for biodegrading microcystin LR by Sphingopyxis sp.USTB-05 被引量:7
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作者 Hai Yan Huasheng wang +4 位作者 junfeng wang Chunhua Yin Song Max Xiaolu Liu Xueyao Yin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第10期1816-1822,共7页
Harmful cyanobacterial blooms are a growing environmental problem worldwide in natural waters, the biodegradation is found to be the most efficient method for removing microcystins 0VICs) produced by harmful cyanobac... Harmful cyanobacterial blooms are a growing environmental problem worldwide in natural waters, the biodegradation is found to be the most efficient method for removing microcystins 0VICs) produced by harmful cyanobacteria. Based on the isolation of a promising bacterial strain of Sphingopyxis sp. USTB-05 for biodegrading MCs, we for the first time cloned and expressed a gene USTB-O5-A (HM245411) that is responsible for the first step in the biodegradation of microcystin LR (MC-LR) in E. coli DH5ct, with a cloning vector of pGEM-T easy and an expression vector of pGEX-4T-1, respectively. The cell-free extracts (CE) of recombinant E. coli DH5ct containing USTB-O5-A had high activity for biodegrading MC-LR. The initial MC-LR concentration of 40 mg/L was completely biodegraded within 1 hr in the presence of CE with a protein concentration of 0.35 mg/mL. Based on an analysis of the liquid chromatogram-mass spectrum (LC-MS), the enzyme encoded by gene USTB-O5-A was found to be active in cleaving the target peptide bond between 3-amino-9-methoxy-2,6, 8-trimethyl-10-phenyl-deca-4,6-dienoic acid (Adda) and arginine of MC-LR, and converting cyclic MC-LR to linear MC-LR as a first product that is much less toxic than parent MC-LR, which offered direct evidence for the first step on the pathway of MC-LR biodegradation by Sphingopyxis sp. USTB-05. 展开更多
关键词 microcystin LR Sphingopyxis sp. USTB-05 BIODEGRADATION GENE
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碳酸铈在NaCl-H_(2)O体系中的相平衡热力学模型
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作者 栾峰 王道广 +2 位作者 王均凤 张建伟 崔朋蕾 《过程工程学报》 CAS CSCD 北大核心 2022年第8期1103-1114,共12页
碳酸铈是生产CeO的重要前驱体,对其性质具有决定性影响。碳酸铈的结晶特征取决于反应结晶过程中过饱和度的控制,其在NaCl-H_(2)O体系中的相平衡数据是关键基础数据。本工作首先在298.15~363.15 K温度范围内合成了碳酸铈,XRD分析结果显示... 碳酸铈是生产CeO的重要前驱体,对其性质具有决定性影响。碳酸铈的结晶特征取决于反应结晶过程中过饱和度的控制,其在NaCl-H_(2)O体系中的相平衡数据是关键基础数据。本工作首先在298.15~363.15 K温度范围内合成了碳酸铈,XRD分析结果显示,323.15 K 及以下得到的产品为八水碳酸铈[Ce_(2)(CO_(3))_(3)·8H_(2)O], 343.15 K 及以上得到的产品为碱式碳酸铈[CeCO_(3)OH]。本工作采用经典等温法测定了这两种碳酸铈化合物在 NaCl-H_(2)O 体系中的相平衡数据,并利用 Aspen Plus 平台的ELEC-NRTL 方程建立了可准确预测 Ce_(2)(CO_(3))_(3)·8H_(2)O 和 CeCO_(3)OH 在 NaCl-H_(2)O 体系中相平衡数据的热力学模型。在无限稀释假设的基础上,通过回归Ce_(2)(CO_(3))_(3)·8H_(2)O 和 CeCO_(3)OH 在水中的溶解度数据,确定了这两种化合物的溶度积。采用赋存形态分析方法,将CeCO_(3)~+, CeOH, CeHCO等组分引入热力学模型。利用实验数据获得了新的离子对(Ce-HCO~-和Ce-Cl~-)参数,提高了新模型的预测能力,所建立的热力学模型预测值与实验数据吻合较好。 展开更多
关键词 碳酸铈 相平衡 溶解度 热力学模型
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A coupled DEM and LBM model for simulation of outbursts of coal and gas 被引量:9
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作者 Sheng Xue Liang Yuan +2 位作者 junfeng wang Yucang wang Jun Xie 《International Journal of Coal Science & Technology》 EI 2015年第1期22-29,共8页
An outburst of coal and gas is a major hazard in underground coal mining. It is generally accepted that an outburst occurs when certain conditions of stress, coal gassiness and physical-mechanical properties of coal a... An outburst of coal and gas is a major hazard in underground coal mining. It is generally accepted that an outburst occurs when certain conditions of stress, coal gassiness and physical-mechanical properties of coal are met. Outbursting is recognized as a two-step process, i.e., initiation and development. In this paper, we present a fully-coupled solid and fluid code to model the entire process of an outburst. The deformation, failure and fracture of solid (coal) are modeled with the discrete element method, and the flow of fluid (gas and water) such as free flow and Darcy flow are modeled with the lattice Boltzmann method. These two methods are coupled in a two-way process, i.e., the solid part provides a moving boundary condition and transfers momentum to the fluid, while the fluid exerts a dragging force upon the solid. Gas desorption from coal occurs at the solid-fluid boundary, and gas diffusion is implemented in the solid code where particles are assumed to be porous. A simple 2D example to simulate the process of an outburst with the model is also presented in this paper to demonstrate the capability of the coupled model. 展开更多
关键词 Coal and gas outburst Discrete element method Lattice Boltzmann method Solid-fluid coupling
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Towards magnetism in pigeon MagR: Iron- and iron-sulfur binding work indispensably and synergistically 被引量:6
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作者 Yajie Zhou Tianyang Tong +12 位作者 Mengke Wei Peng Zhang Fan Fei Xiujuan Zhou Zhen Guo Jing Zhang Huangtao Xu Lei Zhang Shun wang junfeng wang Tiantian Cai Xin Zhang Can Xie 《Zoological Research》 SCIE CAS CSCD 2023年第1期142-152,共11页
The ability to navigate long distances is essential for many animals to locate shelter,food,and breeding grounds.Magnetic sense has evolved in various migratory and homing species to orient them based on the geomagnet... The ability to navigate long distances is essential for many animals to locate shelter,food,and breeding grounds.Magnetic sense has evolved in various migratory and homing species to orient them based on the geomagnetic field.A highly conserved ironsulfur cluster assembly protein IscA is proposed as an animal magnetoreceptor(MagR).Iron-sulfur cluster binding is also suggested to play an essential role in MagR magnetism and is thus critical in animal magnetoreception.In the current study,we provide evidence for distinct iron binding and iron-sulfur cluster binding in MagR in pigeons,an avian species that relies on the geomagnetic field for navigation and homing.Pigeon MagR showed significantly higher total iron content from both iron-and ironsulfur binding.Y65 in pigeon MagR was shown to directly mediate mononuclear iron binding,and its mutation abolished iron-binding capacity of the protein.Surprisingly,both iron binding and iron-sulfur binding demonstrated synergistic effects,and thus appear to be integral and indispensable to pigeon MagR magnetism.These results not only extend our current understanding of the origin and complexity of MagR magnetism,but also imply a possible molecular explanation for the huge diversity in animal magnetoreception. 展开更多
关键词 Animal magnetoreception Iron-sulfur cluster binding Iron binding MAGNETISM Magnetoreceptor(MagR)
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The pulsed high magnetic field facility and scientific research at Wuhan National High Magnetic Field Center 被引量:6
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作者 Xiaotao Han Tao Peng +13 位作者 Hongfa Ding Tonghai Ding Zengwei Zhu Zhengcai Xia junfeng wang Junbo Han Zhongwen Ouyang Zhenxing wang Yibo Han Houxiu Xiao Quanliang Cao Yiliang Lv Yuan Pan Liang Li 《Matter and Radiation at Extremes》 SCIE EI CAS 2017年第6期278-286,共9页
Wuhan National High Magnetic Field Center(WHMFC)at Huazhong University of Science and Technology is one of the top-class research centers in the world,which can offer pulsed fields up to 90.6 T with different field wa... Wuhan National High Magnetic Field Center(WHMFC)at Huazhong University of Science and Technology is one of the top-class research centers in the world,which can offer pulsed fields up to 90.6 T with different field waveforms for scientific research and has passed the final evaluation of the Chinese government in 2014.This paper will give a brief introduction of the facility and the development status of pulsed magnetic fields research at WHMFC.In addition,it will describe the application development of pulsed magnetic fields in both scientific and industrial research. 展开更多
关键词 Pulsed high magnetic field Pulsed magnet Scientific research Electromagnetic technology
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One-step preparation of MoO_(x)/ZnS/ZnO composite and its excellent performance in piezocatalytic degradation of Rhodamine B under ultrasonic vibration 被引量:3
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作者 Song Zheng Xiaojing Li +5 位作者 Jiayu Zhang junfeng wang Chunran Zhao Xin Hu Ying Wu Yiming He 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第3期1-13,共13页
This paper synthesized a new type of ternary piezoelectric catalyst MoO_(x)/ZnS/ZnO (MZZ)by a one-step method.The catalytic degradation of Rhodamine B (RhB) solution (10μg/g,pH=7.0) shows that the composite catalyst ... This paper synthesized a new type of ternary piezoelectric catalyst MoO_(x)/ZnS/ZnO (MZZ)by a one-step method.The catalytic degradation of Rhodamine B (RhB) solution (10μg/g,pH=7.0) shows that the composite catalyst has excellent piezoelectric catalytic activity under ultrasonic vibration (40 k Hz).The piezoelectric degradation rate of the optimal sample reached 0.054 min^(-1),which was about 2.5 times that of pure ZnO.X-ray diffraction(XRD),X-ray photoelectron spectroscopy (XPS),Raman,transmission electron microscopy(TEM),scanning electron microscopy (SEM),and electrochemical impedance spectroscopy(EIS) technologies were used to analyze the structure,morphology,and interface charge transfer properties of the MZZ piezocatalysts.The results showed that the composite catalyst may have a core-shell structure.ZnS is coated on the surface of ZnO,while MoO_(x)adheres to the surface of ZnS.This structure endowed MZZ larger specific surface area than ZnO,which benefits the RhB adsorption.More importantly,the formed heterojunction structure between ZnS and ZnO promotes the separation of positive and negative charges induced by the piezoelectric effect.MoO_(x)species may act as a charge trap to further promote more carriers to participate in the reaction.In addition,MoO_(x)may also be beneficial in adsorbing dyes.Active species capture experiments show that superoxide radicals and holes are the main active species in piezoelectric catalytic reactions on MZZ catalysts. 展开更多
关键词 ZNO ZNS MoO_(x) Piezocatalytic Rhodamine B Core-shell structure
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