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Corn straw-derived carbon/BiOBr composite:Synthesis and photocatalytic degradation performance for rhodamine B
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作者 ZHANG Jin WANG Yuting +2 位作者 YU Bin ZHONG Yuxin ZHANG Yufeng 《无机化学学报》 北大核心 2025年第7期1397-1408,共12页
A flower-like BiOBr photocatalyst(CS/BiOBr)was prepared by using the carbon material derived from corn straw(CS)as the carrier.The prepared composites were characterized by X-ray diffraction(XRD),Fourier transform inf... A flower-like BiOBr photocatalyst(CS/BiOBr)was prepared by using the carbon material derived from corn straw(CS)as the carrier.The prepared composites were characterized by X-ray diffraction(XRD),Fourier transform infrared(FIIR)spectra,scanning electron microscope(SEM),X-ray photoelectron spectra(XPS),and UV-Vis diffuse reflectance spectra(UV-Vis DRS).The SEM analyses indicate that the introduction of CS promotes the formation of a unique flower-like structure in BiOBr,which not only optimizes the efficiency of light capture but also increases the specific surface area of BiOBr.The bandgap of the composite was narrower compared with the pure BiOBr.The CS/BiOBr composites exhibited higher photocatalytic activity than pure CS and BiOBr under visible light irradiation,and a higher first-order reaction rate constant(k)of 0.0437 min-1 than BiOBr(0.0146 min^(-1)),and exhibited excellent stability and reusability during the cyclic run.The enhanced photocatalytic activity is attributed to the efficient separation of photoinduced electrons and holes.Superoxide radicals and holes were the major active species. 展开更多
关键词 corn straws agricultural waste BiOBr PHOTOCATALYSIS rhodamine B
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Elucidating the catalytic role of lithium(Li)in the glucose-to-fructose isomerization over Li-C_(3)N_(4) catalyst at 60℃ in water
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作者 WANG Yuxuan GUO Fenfen +7 位作者 JIANG Zhicheng TU Youjing ZHANG Xingyu TANG Aoyi WANG Junxia LIANG Yuan YAN Lishi KONG Lingzhao 《燃料化学学报(中英文)》 北大核心 2025年第9期1373-1384,共12页
Fully utilizing renewable biomass energy is important for saving energy,reducing carbon emissions,and mitigating climate change.As the main hydrolysate of cellulose,a primary component of lignocellulose,glucose could ... Fully utilizing renewable biomass energy is important for saving energy,reducing carbon emissions,and mitigating climate change.As the main hydrolysate of cellulose,a primary component of lignocellulose,glucose could be employed as a starting material to prepare some other functional derivatives for improving the value of biomass resources.The isomerization of glucose to produce fructose is an important intermediate process during numerous high-value-added chemical preparations.Therefore,the development of efficient and selective catalysts for glucose isomerization is of great significance.Currently,glucose isomerase catalysts are limited by the harsh conditions required for microbial activity,which restricts further improvements in fructose yield.Additionally,heterogeneous Bronsted-base and Lewis-acid catalysts commonly employed in chemical isomerization methods often lead to the formation of undesirable by-products,resulting in reduced selectivity toward fructose.This study has demonstrated that lithium-loaded heterogeneous catalysts possess excellent isomerization capabilities under mild conditions.A highly efficient Li-C_(3)N_(4) catalyst was developed,achieving a fructose selectivity of 99.9% and a yield of 42.6% at 60℃ within 1.0 h-comparable to the performance of the enzymatic method.Characterization using X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD),proton nuclear magnetic resonance(^(1)H NMR),and inductively coupled plasma(ICP)analyses confirmed that lithium was stably incorporated into the g-C_(3)N_(4) framework through the formation of Li-N bonds.Further investigations using CO_(2) temperature-programmed desorption(CO_(2)-TPD),in situ Fourier-transform infrared spectroscopy(FT-IR)and 7Li magic angle spinning nuclear magnetic resonance(^(7)Li MAS NMR)indicated that the isomerization proceeded via a base-catalyzed mechanism.The Li species were found to interact with hydroxyl groups generated through hydrolysis and simultaneously coordinated with nitrogen atoms in the C_(3)N_(4) matrix,resulting in the formation of Li-N_(6)-H_(2)O active sites.These active sites facilitated the deprotonation of glucose to form an enolate intermediate,followed by a proton transfer step that generated fructose.This mechanism not only improved the efficiency of fructose production but also provided valuable insight into the catalytic role of lithium within the isomerization process. 展开更多
关键词 GLUCOSE FRUCTOSE ISOMERIZATION hydrothermal catalysis Li-C_(3)N_(4)
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Sc-doped strontium iron molybdenum cathode for high-efficiency CO_(2)electrolysis in solid oxide electrolysis cell
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作者 LIU Zhen ZHANG Lihong +4 位作者 XU Chunming WANG Zhenhua QIAO Jinshuo SUN Wang SUN Kening 《燃料化学学报(中英文)》 北大核心 2025年第2期272-281,共10页
Solid oxide electrolysis cells(SOECs)can effectively convert CO_(2)into high value-added CO fuel.In this paper,Sc-doped Sr_(2)Fe_(1.5)Mo_(0.3)Sc_(0.2)O_(6−δ)(SFMSc)perovskite oxide material is synthesized via solid-p... Solid oxide electrolysis cells(SOECs)can effectively convert CO_(2)into high value-added CO fuel.In this paper,Sc-doped Sr_(2)Fe_(1.5)Mo_(0.3)Sc_(0.2)O_(6−δ)(SFMSc)perovskite oxide material is synthesized via solid-phase method as the cathode for CO_(2)electrolysis by SOECs.XRD confirms that SFMSc exhibits a stable cubic phase crystal structure.The experimental results of TPD,TG,EPR,CO_(2)-TPD further demonstrate that Sc-doping increases the concentration of oxygen vacancy in the material and the chemical adsorption capacity of CO_(2)molecules.Electrochemical tests reveal that SFMSc single cell achieves a current density of 2.26 A/cm^(2) and a lower polarization impedance of 0.32Ω·cm^(2) at 800°C under the applied voltage of 1.8 V.And no significant performance attenuation or carbon deposition is observed after 80 h continuous long-term stability test.This study provides a favorable support for the development of SOEC cathode materials with good electro-catalytic performance and stability. 展开更多
关键词 solid oxide electrolysis cells CATHODE PEROVSKITE ELECTRO-CATALYSIS element doping
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Enhancing energy density in planar micro-supercapacitors:The role of few-layer graphite/carbon black/NiCo_(2)O_(4) composite materials
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作者 ZHANG Wanggang HUANG Lei +3 位作者 WANG Menghu WANG Jian WEI Aili LIU Yiming 《燃料化学学报(中英文)》 北大核心 2025年第5期646-662,共17页
The advancement of planar micro-supercapacitors(PMSCs)for micro-electromechanical systems(MEMS)has been significantly hindered by the challenge of achieving high energy and power densities.This study addresses this is... The advancement of planar micro-supercapacitors(PMSCs)for micro-electromechanical systems(MEMS)has been significantly hindered by the challenge of achieving high energy and power densities.This study addresses this issue by leveraging screen-printing technology to fabricate high-performance PMSCs using innovative composite ink.The ink,a synergistic blend of few-layer graphene(Gt),carbon black(CB),and NiCo_(2)O_(4),was meticulously mixed to form a conductive and robust coating that enhanced the capacitive performance of the PMSCs.The optimized ink formulation and printing process result in a micro-supercapacitor with an exceptional areal capacitance of 18.95 mF/cm^(2)and an areal energy density of 2.63μW·h/cm^(2)at a current density of 0.05 mA/cm^(2),along with an areal power density of 0.025 mW/cm^(2).The devices demonstrated impressive durability with a capacitance retention rate of 94.7%after a stringent 20000-cycle test,demonstrating their potential for long-term applications.Moreover,the PMSCs displayed excellent mechanical flexibility,with a capacitance decrease of only 3.43%after 5000 bending cycles,highlighting their suitability for flexible electronic devices.The ease of integrating these PMSCs into series and parallel configurations for customized power further underscores their practicality for integrated power supply solutions in various technologies. 展开更多
关键词 graphite/carbon black composite NiCo_(2)O_(4) screen printing planar micro-supercapacitor energy density mechanical flexibility
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Multi-omics Analysis of NUDT19 Across Cancer Types and Its Functional Role in Leukemia
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作者 LI Xiao-Jin FENG Shuai +1 位作者 YUAN Zhong-Tao YANG Tong-Hua 《生物化学与生物物理进展》 北大核心 2025年第10期2627-2649,共23页
Objective Recent studies have highlighted the critical role of NUDT19 in the initiation,progression,and prognosis of specific cancer types.However,its involvement in pan-cancer analysis has not been fully characterize... Objective Recent studies have highlighted the critical role of NUDT19 in the initiation,progression,and prognosis of specific cancer types.However,its involvement in pan-cancer analysis has not been fully characterized.This study aims to systematically explore the expression patterns,clinical significance,and immune-related functions of NUDT19 in various cancer types through multi-omics analysis,further revealing its potential role in cancer,particularly its functional and therapeutic target value in leukemia.Methods To achieve this goal,various bioinformatics approaches were employed to evaluate the expression patterns,clinical significance,and immune-related functions of NUDT19 in tumors and normal tissues.Additionally,we analyzed the mutation characteristics of NUDT19 and its relationship with epigenetic modifications.Using the single-cell analysis tool SingleCellBase,we explored the distribution of NUDT19 across different cell subpopulations in tumors.To validate these findings,qRT-PCR was used to measure NUDT19 expression levels in specific tumor cell lines,and we established acute myeloid leukemia(AML)cell lines(HL-60 and THP-1)to conduct NUDT19 knockdown and overexpression experiments,assessing its effects on leukemia cell proliferation,apoptosis,and invasion.Results Pan-cancer analysis revealed the dysregulated expression of NUDT19 across multiple cancer types,which was closely associated with poor prognosis,clinical staging,and diagnostic markers.Furthermore,NUDT19 was significantly correlated with tumor biomarkers,immune-related genes,and immune cell infiltration in different cancers.Mutation analysis showed that multiple mutations in NUDT19 were significantly associated with epigenetic changes.Single-cell analysis revealed the heterogeneity of NUDT19 expression in cancer cells,suggesting its potentially diverse functional roles in different cell subpopulations.qRT-PCR experiments confirmed the significant upregulation of NUDT19 in various tumor cell lines.In AML cell lines,NUDT19 knockdown led to reduced cell proliferation and invasion,with increased apoptosis,while NUDT19 overexpression significantly enhanced cell proliferation and invasion while reducing apoptosis.Conclusion This study demonstrates the diverse roles of NUDT19 in various cancer types,with a particularly prominent functional role in leukemia.NUDT19 is not only associated with tumor initiation and progression but may also influence cancer progression through the regulation of immune microenvironment and epigenetic mechanisms.Our research highlights the potential of NUDT19 as a therapeutic target,particularly for targeted therapies in malignancies such as leukemia,with significant clinical application prospects. 展开更多
关键词 NUDT19 pan-cancer immunotherapeutic single-cell analysis
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Dual-surface capped hydroxyapatite nano-amendment with tuned alternate long-short chain configuration for efficient adsorption towards multi-heavy metal ions in complex-contaminated systems
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作者 GAO Mochou MENG Shan +7 位作者 ZHANG Jinzhong FENG Wenhua DONG Shuo CHEN Jianping ZHAO Yanbao YU Laigui YING Rongrong ZOU Xueyan 《无机化学学报》 北大核心 2025年第7期1427-1438,共12页
Hydroxyapatite nanoparticles(HAP NPs)were synthesized by a one‐step hydrothermal method.The surface of HAP NPs was grafted-SH and-COOH chelating groups via in situ surface‐modification with iminodiacetic acid(IDA)an... Hydroxyapatite nanoparticles(HAP NPs)were synthesized by a one‐step hydrothermal method.The surface of HAP NPs was grafted-SH and-COOH chelating groups via in situ surface‐modification with iminodiacetic acid(IDA)and 3‐mercaptopropyl trimethoxysilane(MPS)to afford dual surface‐capped nano‐amendment HAPIDA/MPS.The structure of HAP‐IDA/MPS was characterized,and its adsorption performance for Hg^(2+),Cu^(2+),Zn^(2+),Ni^(2+),Co^(2+),and Cd^(2+)was evaluated.The total adsorption capacity of 0.10 g HAP‐IDA/MPS nano‐amendment for Hg^(2+),Cu^(2+),Zn^(2+),Ni^(2+),Co^(2+),and Cd^(2+)with an initial mass concentration of 20 mg·L^(-1) reached 13.7 mg·g^(-1),about 4.3 times as much as that of HAP.Notably,HAP‐IDA/MPS nano‐amendment displayed the highest immobilization rate for Hg^(2+),possibly because of its chemical reaction with-SH to form sulfide,possessing the lowest solubility product constant among a variety of metal sulfides. 展开更多
关键词 heavy metal HYDROXYAPATITE nano-amendment configuration tuning synergistic adsorption
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Continuous-flow columns packed with zero-valent iron and iron sulfide as a feasible strategy to remediate the persistent contaminant nitroguanidine
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作者 Youngjae Yu Erika E.Rios-Valenciana +3 位作者 Robert A.Root Reyes Sierra-Alvarez Jon Chorover Jim A.Field 《Defence Technology(防务技术)》 2025年第1期26-34,共9页
The insensitive munitions compound nitroguanidine(NQ)is used by the U.S.Army to avoid unintended explosions.However,NQ also represents an emerging contaminant whose environmental emissions can cause toxicity toward aq... The insensitive munitions compound nitroguanidine(NQ)is used by the U.S.Army to avoid unintended explosions.However,NQ also represents an emerging contaminant whose environmental emissions can cause toxicity toward aquatic organisms,indicating the need for effective remediation strategies.Thus,we investigated the feasibility of treating water contaminated with NQ in continuous-flow columns packed with zero-valent iron(ZVI)or iron sulfide(FeS).Initially,the impact of pH on NQ transformation by ZVI or FeS was evaluated in batch experiments.The pseudo first-order rate constant for NQ transformation(k_(1,NQ))by ZVI was 8-10 times higher at pH 3.0 compared to pH 5.5 and 7.0,whereas similar k_(1,NQ)values were obtained for FeS at pH 5.5-10.0.Based on these findings,the influent p H fed to the ZVIand Fe S-packed columns was adjusted to 3.0 and 5.5,respectively.Both reactors transformed NQ into nitrosoguanidine(Nso Q).Further transformation of Nso Q by ZVI produced aminoguanidine,guanidine,and cyanamide,whereas Nso Q transformation by Fe S produced guanidine,ammonium,and traces of urea.ZVI outperformed Fe S as a reactive material to remove NQ.The ZVI-packed column effectively removed NQ below detection even after 45 d of operation(490 pore volumes,PV).In contrast,NQ breakthrough(removal efficiency<85%)was observed after 18 d(180 PV)in the Fe S-packed column.The high NQ removal efficiency and long service life of the ZVI-packed column(>490 PV)suggest that the technology is a promising approach for NQ treatment in packed-bed reactors and in situ remediation. 展开更多
关键词 Continuous water treatment Iron-based minerals Chemical reduction pH AMINOGUANIDINE GUANIDINE
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Utilizing the ozonation pathway for enhanced conversion of manganese dithionate to manganese dioxide from acid leaching solution:Insights into mechanism and kinetics
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作者 QU Bing LI Teng +4 位作者 YANG Zheng-zheng REN Li-ping WANG Ying-wu WU Meng-qiang CHEN Si-bei 《Journal of Central South University》 2025年第4期1340-1352,共13页
In response to the fact that the presence of manganese dithionate(MnS_(2)O_(6))leads to a series of adverse impacts,especially lower purity of manganese sulfate(MnSO_(4))and disruption of its recovery,advanced oxidati... In response to the fact that the presence of manganese dithionate(MnS_(2)O_(6))leads to a series of adverse impacts,especially lower purity of manganese sulfate(MnSO_(4))and disruption of its recovery,advanced oxidation methods such as ozonation system are used to manage MnS_(2)O_(6)in the leaching solution,replacing conventional methods.To ascertain the conversion rate and kinetics of MnS_(2)O_(6)during the ozonation process,we explored the factors influencing its removal rate,including ozone dosage,manganese dithionate concentration,sulfuric acid concentration,and reaction temperature.Batch experiments were conducted to determine the reaction rate constant of ozone(k)and activation energy(Ea)obtained from intermittent experimental data fitting,revealing a least-squares exponential conversion relationship between k and the MnS_(2)O_(6)removal amount,wherein an increase in the aforementioned factors led to an enhanced MnS_(2)O_(6)conversion rate,exceeding 99.3%.The formation mechanism of the ozone products proposed during the experiment was summarized and proposed as follows:1)Mn^(2+)was directly oxidized to MnO_(2),and 2)SO_(4)2−was obtained by the catalytic oxidation of S_(2)O_(6)^(2−)with HO•from O3 decomposition.According to the kinetics analysis,the pre-exponential factor and total activation energy of the ozonation kinetics equation were 1.0×10^(23) s^(−1) and 177.28 kJ/mol,respectively.Overall,the present study demonstrates that O_(3) as an oxidizing agent can effectively facilitate MnS_(2)O_(6)disproportionation while preventing the release of the secondary pollutant,SO_(2)gas. 展开更多
关键词 OZONATION manganese dithionate manganese dioxide CONVERSION mechanism and kinetics
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Arsenic removal in copper electrolyte:A review and future prospects
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作者 MA Jun DUAN Ning +2 位作者 XU Fu-yuan JIANG Lin-hua XIAO Ke 《Journal of Central South University》 2025年第5期1736-1759,共24页
Copper is a strategic metal that plays an important role in many industries.In copper metallurgy,electrolytic refining is essential to obtain high-purity copper.However,during the electrolytic refining process,impurit... Copper is a strategic metal that plays an important role in many industries.In copper metallurgy,electrolytic refining is essential to obtain high-purity copper.However,during the electrolytic refining process,impurities such as arsenic are introduced into the electrolyte,which significantly affect the subsequent production and quality of copper products.This paper first discusses the sources,forms,and transformation pathways of arsenic in copper electrolyte during the electrolytic process,then reviews various arsenic removal technologies in detail,including electrowinning,adsorption,solvent extraction,ion exchange,membrane filtration,and precipitation.Particular emphasis is placed on electrowinning,which is the most widely used and mature among these arsenic removal techniques.The paper evaluates these methods based on arsenic removal efficiency,cost effectiveness,technical maturity,environmental friendliness,and operation simplicity.In addition,the paper explores future trends in copper electrolyte purification,focusing on waste reduction at source,resource utilization,intelligent digitalization,and innovations in materials and processes.This review aims to provide researchers and practitioners with a comprehensive and in-depth reference on arsenic removal methods in copper electrolytes. 展开更多
关键词 arsenic removal removal techniques electrolyte purification copper electrorefining ELECTROWINNING
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Chalcopyrite bioleaching by an enriched microbial community in acidic artificial seawater
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作者 GU Chen-yun ZHANG Rui-yong +7 位作者 XIA Jin-lan LIU Hong-chang SAND Wolfgang WANG Yi-rong CHEN Lu NIE Zhen-yuan ZHANG Yan-sheng WANG Jun 《Journal of Central South University》 2025年第5期1802-1821,共20页
The enhancement of chalcopyrite bioleaching with an enriched microbial community by acidified seawater was studied,and the enhancing mechanism was analyzed.The microbial community was enriched at the Dabaoshan mine si... The enhancement of chalcopyrite bioleaching with an enriched microbial community by acidified seawater was studied,and the enhancing mechanism was analyzed.The microbial community was enriched at the Dabaoshan mine site,and the treated ore sample had high concentrations of chalcopyrite and galena.The experimental results show that copper extraction from chalcopyrite with an enriched microbial community in seawater was promoted from 13.1%to 62.1%by acidification in comparison with that without acidification.Further analyses of the solutions,solid residues and microbial compositions by scanning electron microscopy,X-ray diffraction,Raman spectroscopy,Fourier transform infrared spectroscopy and 16 S rDNA sequencing revealed the promoting effects of acidified seawater.This acidification can increase the biodissolution of chalcopyrite to increase the concentration of iron ions and maintain the redox potential in the range of 360−410 mV.The latter produces an optimal redox environment conducive to chalcopyrite dissolution via Cu_(2)S.The adaptability of the microbial community to a high-salt environment is improved.Chloride ions at 580 mmol/L improve the leaching kinetics of chalcopyrite by increasing the porosity and noncrystallinity of the intermediate elemental sulfur.This study provides a promising way to bioleaching copper minerals using seawater for areas with freshwater shortages. 展开更多
关键词 BIOLEACHING CHALCOPYRITE ACIDIFICATION seawater microbial community
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Phylogenomic analysis of bromodomain genes in cotton(Gossypium spp.) and their potential roles in abiotic stress tolerance
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作者 TAYYAB Muhammad TAJ Muhammad Hassan +8 位作者 AHMAD Ali Ijaz RANA Faiza Rehman SHAHZAIB Muhammad ATIF Rana Muhammad AZHAR Muhammad Tehseen KHAN Sultan Habibullah KAKAKHEL Ishaq Ahmad Mian HE Shoupu RANA Iqrar Ahmad 《Journal of Cotton Research》 2025年第3期333-351,共19页
Background The bromodomain(BRD) proteins play a pivotal role in regulating gene expression by recognizing acetylated lysine residues and acting as chromatin-associated post-translational modification-inducing proteins... Background The bromodomain(BRD) proteins play a pivotal role in regulating gene expression by recognizing acetylated lysine residues and acting as chromatin-associated post-translational modification-inducing proteins. Although BRD proteins have been extensively studied in mammals, they have also been characterized in plants like Arabidopsis thaliana and Oryza sativa, where they regulate stress-responsive genes related to drought, salinity, and cold. However, their roles in cotton species remain unexplored.Results In this genome-wide comparative analysis, 145 BRD genes were identified in the tetraploid species(Gossypium hirsutum and G. barbadense), compared with 82 BRD genes in their diploid progenitors(G. arboreum and G. raimondii), indicating that polyploidization significantly influenced BRD gene evolution. Gene duplication analysis revealed 78.85% of duplications were segmental and 21.15% were tandem among 104 in-paralogous gene pairs, contributing to BRD gene expansion. Gene structure, motif, and domain analyses demonstrated that most genes were intron-less and conserved throughout evolution. Syntenic analysis revealed a greater number of orthologous gene pairs in the Dt sub-genome than in the At sub-genome. The abundance of regulatory, hormonal, and defense-related cis-regulatory elements in the promoter region suggests that BRD genes play a role in both biotic and abiotic stress responses. Protein-protein interaction analysis indicated that global transcription factor group E(GTE) transcription factors regulate BRD genes. Expression analysis revealed that BRD genes are predominantly involved in ovule development, with some genes displaying specific expression patterns under heat, cold, and salt stress. Furthermore, qRT-PCR analysis demonstrated significant differential expression of BRD genes between the tolerant and sensitive genotype, underscoring their potential role in mediating drought and salinity stress responses.Conclusions This study provides valuable insights into the evolution of BRD genes across species and their roles in abiotic stress tolerance, highlighting their potential in breeding programs to develop drought and salinity tolerant cotton varieties. 展开更多
关键词 COTTON PHYLOGENETICS EPIGENETICS BROMODOMAIN
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Spatial distribution and environmental characterization of sediment-associated metals from middle-downstream of Xiangjiang River,southern China 被引量:9
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作者 郭朝晖 宋杰 +3 位作者 肖细元 明辉 苗旭锋 王凤永 《Journal of Central South University》 SCIE EI CAS 2010年第1期68-78,共11页
The contamination and environmental risk assessment of the toxic elements in sediments from the middle-downstream (Zhuzhou-Changsha section) of the Xiangjiang River in Hunan Province of China were studied. The results... The contamination and environmental risk assessment of the toxic elements in sediments from the middle-downstream (Zhuzhou-Changsha section) of the Xiangjiang River in Hunan Province of China were studied. The results show that As, Cd, Pb and Zn are major contaminants in sediments, and average concentrations of these elements significantly exceed both the Control Standards for Pollutants in Sludge of China (GB4284-84) for agricultural use in acidic soils and the effect range median (ERM) values. The average concentrations of As, Cd and Pb in the river water slightly exceed the limit of Surface Water Environment Quality Standard (GB3838-2002). The concentrations of As and Cr in depth profiles extensively change, but slight changes are observed in Pb and Zn. Cd and Zn in most sediment samples can easily enter the food-chain and bring possible ecotoxicological risk to organisms living in sediments according to the risk assessment code. 展开更多
关键词 SEDIMENT toxic elements spatial distribution environmental risk Xiangjiang River
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Energy consumption,indoor environmental quality,and benchmark for office buildings in Hainan Province of China 被引量:1
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作者 孔祥飞 吕石磊 +1 位作者 辛亚娟 吴薇 《Journal of Central South University》 SCIE EI CAS 2012年第3期783-790,共8页
With rapid economy growth,building energy consumption in China has been gradually increased.The energy consumption and indoor environmental quality of 51 office buildings in Hainan Province,a hot and humid area,were s... With rapid economy growth,building energy consumption in China has been gradually increased.The energy consumption and indoor environmental quality of 51 office buildings in Hainan Province,a hot and humid area,were studied through collection of verified data in site visits and field tests.The result revealed that,electricity accounted for 99.79% of the total energy consumption,natural gas 0.17%,and diesel 0.04%.The air conditioning dominated the energy use with a share of 43.18%,equipment in the particular areas 26.90%,equipment in the office rooms 11.95%,lighting system 8.67%,general service system 7.57%,and miscellaneous items 1.73%.Statistical method including six indicators obtained the energy consumption benchmark with upper limit of 98.31 kW-h/m2 and lower limit of 55.26 kW-h/m2.According to ASHRAE standard(comfortable standard) and GB/T 18883-2002(acceptable standard),the indoor environmental quality of 51 sampled office buildings was classified into three ranks:good,normal and bad.With benchmark of building energy consumption combined with indoor environmental quality,it was found that only 3.92% of sampled buildings can be identified as the best performance buildings with low energy consumption and advanced indoor environmental quality,and the buildings classified into normal level accounted for the maximum ratio. 展开更多
关键词 building energy consumption BENCHMARK indoor environmental quality energy use index Hainan Province
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The Environmental Impact of Industrial Agriculture in Rwanda:The Case of Mulindi Tea Plantations
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作者 Mupenzi jean de la Paix Habiyaremye Gabriel Bazimenyera Jean de Dieu 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期244-244,共1页
The aim of this study is to assess the impact of industrial agriculture on the environment in Rwanda taking Mulindi tea plantations as a case study.Tea is one of the three major crops of Rwandan industrial agriculture... The aim of this study is to assess the impact of industrial agriculture on the environment in Rwanda taking Mulindi tea plantations as a case study.Tea is one of the three major crops of Rwandan industrial agriculture apart from coffee and pyrethrum.The results of this study show clearly the impact of tea plantations on the environment in Rwandan in all aspects.Soil samples collected in three zones 展开更多
关键词 environment soil DEGRADATION DEFORESTATION TEA water POLLUTION Rwanda
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Multi-hierarchical fuzzy judgment and nested dominance relation of rough set theory-based environmental risk evaluation for tailings reservoirs
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作者 田森 陈建宏 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4797-4806,共10页
Environmental risk assessment of tailings reservoir assessment system is complex and has many index factors.In order to accurately judge surrounding environmental risks of tailings reservoirs and determinate the corre... Environmental risk assessment of tailings reservoir assessment system is complex and has many index factors.In order to accurately judge surrounding environmental risks of tailings reservoirs and determinate the corresponding prevention and control work,multi-hierarchical fuzzy judgment and nested dominance relation of rough set theory are implemented to evaluate them and find out the rules of this evaluation system with 14 representative cases.The methods of multi-hierarchical fuzzy evaluation can overall consider each influence factor of risk assessment system and their mutual impact,and the index weight based on the analytic hierarchy process is relatively reasonable.Rough set theory based on dominance relation reduces each index attribute from the top down,largely simplifies the complexity of the original evaluation system,and considers the preferential information in each index.Furthermore,grey correlation theory is applied to analysis of importance of each reducted condition attribute.The results demonstrate the feasibility of the proposed safety evaluation system and the application potential. 展开更多
关键词 environmental risk tailings reservoir fuzzy evaluation dominance relation rough set grey correlation theory
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西藏自治区发现不丹大鼯鼠和李氏小飞鼠 被引量:1
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作者 李权 李学友 +10 位作者 曾祥乐 白皓天 Stephen Jackson 胡哲畅 朱中旭 汪思远 罗康 罗京 普明进 普昌哲 蒋学龙 《兽类学报》 CAS CSCD 北大核心 2024年第5期574-586,共13页
2022—2023年,摄影爱好者和中国科学院昆明动物研究所科研人员先后在西藏自治区拍摄和采集到不丹大鼯鼠(Petaurista nobilis)(错那县、亚东县)和李氏小飞鼠(Priapomys leonardi)(巴宜区、墨脱县和错那县)的照片及标本。研究发现不丹大... 2022—2023年,摄影爱好者和中国科学院昆明动物研究所科研人员先后在西藏自治区拍摄和采集到不丹大鼯鼠(Petaurista nobilis)(错那县、亚东县)和李氏小飞鼠(Priapomys leonardi)(巴宜区、墨脱县和错那县)的照片及标本。研究发现不丹大鼯鼠西藏种群形态上与不丹大鼯鼠不丹亚种(Petaurista nobilis singhei Saha,1975)的描述一致;遗传上与米什米大鼯鼠(Petaurista mishmiensis)构成姊妹群,遗传距离较小(Cyt b:1.85%)。考虑到不丹大鼯鼠和米什米大鼯鼠之间的遗传差异过小,分布区连续且栖息地都为中低海拔的常绿阔叶林,故两者应视为同一物种;又因两者之间的毛色差异稳定存在,可作为不同亚种,根据优先律,使用不丹大鼯鼠Petaurista nobilis(Gray,1842)做为种名,米什米大鼯鼠降为不丹大鼯鼠米什米亚种(Petaurista nobilis mishmiensis Choudhury,2009)。李氏小飞鼠西藏种群毛色、头骨和颊齿特征与云南西北部种群一致,但体型较小,且阴茎长度、直径和形状有较大程度的变异;遗传上西藏种群是包含云南西北部种群的并系群,遗传距离较小(12S ribosomal RNA:0.45%~0.91%,16S ribosomal RNA:0.31%~1.05%)。不丹大鼯鼠为中国兽类新纪录,李氏小飞鼠为西藏自治区兽类新纪录。本研究扩展了不丹大鼯鼠和李氏小飞鼠的分布区,提示应进一步加强喜马拉雅地区兽类的调查与监测研究工作,以发现更多的新物种、新纪录。 展开更多
关键词 兽类 鼯鼠 新纪录 西藏自治区 错那县 墨脱县 巴宜区 亚东县
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考虑融雪及土壤冻融的新安江模型及其应用——以雅砻江上游径流模拟为例 被引量:7
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作者 董宁澎 王浩 +2 位作者 杨明祥 张居嘉 徐世琴 《水科学进展》 EI CAS CSCD 北大核心 2024年第4期530-542,共13页
寒区为中国大江大河的主要产流区,其径流预报精度直接影响下游水利工程调度和水资源科学管理。针对传统概念性水文模型较少考虑积雪融雪及土壤冻融过程对径流的叠加影响这一问题,以新安江模型为基础,以降水量和气温为驱动数据,提出了基... 寒区为中国大江大河的主要产流区,其径流预报精度直接影响下游水利工程调度和水资源科学管理。针对传统概念性水文模型较少考虑积雪融雪及土壤冻融过程对径流的叠加影响这一问题,以新安江模型为基础,以降水量和气温为驱动数据,提出了基于“等效土壤温度”和“土壤冻融特征曲线”的概念性土壤冻融模块来刻画积雪融雪及土壤冻融共同影响下的流域产流过程,构建了考虑融雪产流和土壤冻融的新安江模型。以雅砻江甘孜水文站以上流域为典型研究区,开展了流域2017—2022年冰雪消融期逐小时的径流模拟分析。结果表明,相比于HBV模型,考虑融雪产流和土壤冻融的模型可以显著提升流域冰雪消融期的水文模拟精度,各年份消融期径流的纳什效率系数中位数由0.69提升至0.83,相关系数中位数由0.88上升至0.92。本研究所提出的考虑融雪及土壤冻融的新安江模型可以为寒区的水文业务预报提供科学支撑。 展开更多
关键词 寒区 融雪产流 土壤冻融 新安江模型 水文预报
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青海喇家遗址极可能由地震导致的砂土液化泥流造成:“12·18”积石山地震的启示 被引量:3
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作者 李俊磊 张绪教 +5 位作者 鱼海麟 王一凡 张向格 李秋蓉 李彩虹 张丽蕾 《现代地质》 CAS CSCD 北大核心 2024年第1期248-259,共12页
形成于3900年前的青海省民和县喇家遗址,号称“东方庞贝”,是一处举世闻名的灾难遗址,但其成因争论由来已久、悬而未决。学者提出的多种“洪水成因”之说,已深入民众之心,但这次灾难事件真的和洪水有关么?2023年12月18日甘肃积石山县的... 形成于3900年前的青海省民和县喇家遗址,号称“东方庞贝”,是一处举世闻名的灾难遗址,但其成因争论由来已久、悬而未决。学者提出的多种“洪水成因”之说,已深入民众之心,但这次灾难事件真的和洪水有关么?2023年12月18日甘肃积石山县的6.2级地震的震中距喇家遗址仅16 km,不仅使喇家遗址博物馆损坏严重,而且触发的泥流在离遗址仅5 km处的民和县中川乡金田村和草滩村,造成了民房和村民被直接掩埋的灭顶之灾,可能是喇家灾难遗址形成过程的重现,成为对比研究喇家遗址成因的重要实证材料。通过对此次地震灾害的野外实地调查和综合研究,或许能解开喇家遗址成因之谜。积石山地震使黄土之下古河床砾石层中地下水沿地表破裂喷出上涌,进而造成黄土液化并顺冲沟快速往下游流动形成泥流,流经草滩村、金田村时泥流遇阻,漫出冲沟将部分房屋冲毁甚至导致村民被掩埋。特殊的地层结构及富集的地下水,在地震的触发之下造成砂土液化并形成泥流,是造成中川乡地震灾害的重要原因。现场调查表明,草滩村一家五口被掩埋的悲剧,并非典型的“砂涌”造成,更无“洪水”的痕迹,而是地震的次生泥流灾害所致。将今论古,结合喇家遗址的文化遗存保存状况及沉积物特征进一步推断,喇家遗址的形成可能与强降雨形成的山间洪流无关,更不是由所谓的“大洪水”造成的。3900年前的古地震及其造成的砂土液化和快速流动的泥流,极可能是造成喇家遗址瞬时灾难的主要成因。 展开更多
关键词 喇家遗址 积石山地震 液化泥流 瞬时灾难 拉脊山北缘断裂 黄河
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基于文献回顾的有色金属冶炼废渣的特征、资源化途径及其安全利用评价 被引量:8
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作者 徐则林 姚佳斌 付融冰 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第4期1178-1196,共19页
冶炼废渣作为冶炼过程中产生的工业副产物,由于其缺乏安全、合理的防护和管理措施可能导致环境问题。通过全面分析近年来发表的相关文献,本文对有色金属冶炼废渣的特性、资源化利用途径及安全利用评价等方面的最新研究进展进行了介绍。... 冶炼废渣作为冶炼过程中产生的工业副产物,由于其缺乏安全、合理的防护和管理措施可能导致环境问题。通过全面分析近年来发表的相关文献,本文对有色金属冶炼废渣的特性、资源化利用途径及安全利用评价等方面的最新研究进展进行了介绍。研究结果表明,不同的原生精矿、冶炼条件和冶炼类型决定了冶炼废渣的化学和矿物学特征。此外,冶炼废渣在各种资源化利用中表现出极高的灵活性,不仅可以用于金属回收和建筑材料,还可以作为农业肥料和修复剂。同时,本文强调了在各种利用情景下对废渣进行安全性评估的重要性,以降低其潜在环境风险。此外,本文还强调了未来的研究方向,包括建立一种综合且量化的土渣混合体中重金属环境风险评价方法,以及探索更多创新的冶炼废渣资源化利用方法。综上所述,本文对于推动冶炼废渣在环境保护和资源可持续利用方面的研究有重要意义。 展开更多
关键词 冶炼废渣 有色金属 废渣特征 资源化利用途径 安全利用评价
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A review of anode materials for sodium ion batteries 被引量:4
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作者 Syed Ali Riza XU Ri-gan +6 位作者 LIU Qi Muhammad Hassan YANG Qiang MU Dao-bin LI Li WU Feng CHEN Ren-jie 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期743-769,共27页
Lithium-ion batteries(LIBs)are used in electric vehicles and portable smart devices,but lithium resources are dwindling and there is an increasing demand which has to be catered for.Sodium ion batteries(SIBs),which ar... Lithium-ion batteries(LIBs)are used in electric vehicles and portable smart devices,but lithium resources are dwindling and there is an increasing demand which has to be catered for.Sodium ion batteries(SIBs),which are less costly,are a promising replacement for LIBs because of the abundant natural reserves of sodium.The anode of a SIB is a necessary component of the battery but is less understood than the cathode.This review outlines the development of various types of anodes,including carbonbased,metallic and organic,which operate using different reaction mechanisms such as intercalation,alloying and conversion,and considers their challenges and prospects.Strategies for modifying their structures by doping and coating,and also modifying the solid electrolyte interface are discussed.In addition,this review also discusses the challenges encountered by the anode of SIBs and the solutions. 展开更多
关键词 Sodium ion batteries ANODE Carbon material Metallic compound ORGANIC
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