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Enhancing Cycle Life of Graphite‖LiFePO_(4)Batteries via Copper Substituted Li_(2)Ni_(1-x)Cu_(x)O_(2)Cathode Prelithiation Additive
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作者 Jian-Ming Zheng Jing-Wen Zhang Tian-Peng Jiao 《电化学(中英文)》 北大核心 2025年第2期17-27,共11页
Lithium nickel oxide(Li_(2)NiO_(2)),as a sacrificial cathode prelithiation additive,has been used to compensate for the lithium loss for improving the lifespan of lithium-ion batteries(LIBs).However,high-cost Li_(2)Ni... Lithium nickel oxide(Li_(2)NiO_(2)),as a sacrificial cathode prelithiation additive,has been used to compensate for the lithium loss for improving the lifespan of lithium-ion batteries(LIBs).However,high-cost Li_(2)NiO_(2)suffers from inferior delithiation kinetics during the first cycle.Herein,we investigated the effects of the cost-effective copper substituted Li_(2)Ni_(1-x)Cu_(x)O_(2)(x=0,0.2,0.3,0.5,0.7)synthesized by a high-temperature solid-phase method on the structure,morphology,electrochemical performance of graphite‖LiFePO_(4)battery.The X-ray diffraction(XRD)refinement result demonstrated that Cu substitution strategy could be favorable for eliminating the NiO_(x)impurity phase and weakening Li-O bond.Analysis on density of states(DOS)indicates that Cu substitution is good for enhancing the electronic conductivity,as well as reducing the delithi-ation voltage polarization confirmed by electrochemical characterizations.Therefore,the optimal Li_(2)Ni_(0.7)Cu_(0.3)O_(2)delivered a high delithiation capacity of 437 mAh·g^(-1),around 8%above that of the pristine Li_(2)NiO_(2).Furthermore,a graphite‖LiFePO_(4)pouch cell with a nominal capacity of 3000 mAh demonstrated a notably improved reversible capacity,energy density and cycle life through introducing 2 wt%Li_(2)Ni_(0.7)Cu_(0.3)O_(2)additive,delivering a 6.2 mAh·g^(-1)higher initial discharge capacity and achieving around 5%improvement in capacity retentnion at 0.5P over 1000 cycles.Additionally,the post-mortem analyses testified that the Li_(2)Ni_(0.7)Cu_(0.3)O_(2)additive could suppress solid electrolyte interphase(SEI)decomposition and homogenize the Li distribution,which benefits to stabilizing interface between graphite and electrolyte,and alleviating dendritic Li plating.In conclusion,the Li_(2)Ni_(0.7)Cu_(0.3)O_(2)additive may offer advantages such as lower cost,lower delithiation voltage and higher prelithiation capacity compared with Li_(2)NiO_(2),making it a promising candidate of cathode prelithiation additive for next-generation LIBs. 展开更多
关键词 Li_(2)Ni_(1-x)Cu_(x)O_(2) Cathode prelithiation additive LiFePO_(4)battery cycle life Grid energy storage
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The Role of GSPT2 in Tumor Cell Cycle Regulation: Mechanisms and Clinical Significance
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作者 Yu Cai Yumei Wu 《Journal of Cancer Therapy》 2025年第1期18-27,共10页
GSPT2 (G1 to S phase transition protein 2) has emerged as a critical regulator of the cell cycle and has garnered increased attention for its role in tumor biology in recent years. This review explores the multifacete... GSPT2 (G1 to S phase transition protein 2) has emerged as a critical regulator of the cell cycle and has garnered increased attention for its role in tumor biology in recent years. This review explores the multifaceted functions of GSPT2, highlighting its involvement in cell cycle regulation and signaling pathways, as well as its potential as a tumor biomarker. By analyzing the latest research findings, we examine the expression patterns of GSPT2 across various tumor types and its correlation with clinical outcomes, underscoring its significance in tumor initiation and progression. Furthermore, we discuss the prospects of GSPT2 as a therapeutic target, providing new insights for future research directions. 展开更多
关键词 GSPT2 TUMOR BIOMARKER Cell cycle SIGNALING
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CO_(2)mineralization curing steel slag-fly ash-Portland cement ternary paste:Mechanical properties,microstructure and life cycle assessment
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作者 YI Guo-yang TIAN Wei +2 位作者 SHI Jun-jie GUO Jian CHENG Xu 《Journal of Central South University》 2025年第7期2487-2510,共24页
Using solid waste as a substitute for conventional cement has become an important way to reduce carbon emissions.This paper attempted to utilize steel slag(SS)and fly ash(FA)as supplementary cementitious material by u... Using solid waste as a substitute for conventional cement has become an important way to reduce carbon emissions.This paper attempted to utilize steel slag(SS)and fly ash(FA)as supplementary cementitious material by utilizing CO_(2)mineralization curing technology.This study examined the dominant and interactive influences of the residual water/cement ratio,CO_(2)pressure,curing time,and SS content on the mechanical properties and CO_(2)uptake rate of CO_(2)mineralization curing SS-FA-Portland cement ternary paste specimens.Additionally,microstructural development was analyzed.The findings demonstrated that each factor significantly affected compressive strength and CO_(2)uptake rate,with factor interactions becoming more pronounced at higher SS dosages(>30%),lower residual water/cement ratios(0.1-0.15),and CO_(2)pressures of 0.1-0.3 MPa.Microscopic examinations revealed that mineralization primarily yielded CaCO_(3)and silica gel.The residual w/c ratio and SS content significantly influenced the CaCO_(3)content and crystallinity of the mineralization products.Post-mineralization curing,the percentage of pores larger than 50 nm significantly decreased,the proportion of harmless pores smaller than 20 nm increased,and pore structure improved.This study also found that using CO_(2)mineralization curing SS-FA-Portland cement solid waste concrete can significantly reduce the negative impact on the environment. 展开更多
关键词 ternary paste CO_(2)curing response surface methodology life cycle assessment
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The role of sulfur cycle in new particle formation:Cycloaddition reaction of SO_(3)to H_(2)S
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作者 Haijie Zhang Wei Wang +5 位作者 Liang Fan Junling Li Yanqin Ren Hong Li Rui Gao Yisheng Xu 《Journal of Environmental Sciences》 2025年第2期489-501,共13页
The chemistry of sulfur cycle contributes significantly to the atmospheric nucleation process,which is the first step of new particle formation(NPF).In the present study,cycloaddition reaction mechanism of sulfur trio... The chemistry of sulfur cycle contributes significantly to the atmospheric nucleation process,which is the first step of new particle formation(NPF).In the present study,cycloaddition reaction mechanism of sulfur trioxide(SO_(3))to hydrogen sulfide(H_(2)S)which is a typical air pollutant and toxic gas detrimental to the environment were comprehensively investigate through theoretical calculations and Atmospheric Cluster Dynamic Code simulations.Gas-phase stability and nucleation potential of the product thiosulfuric acid(H_(2)S_(2)O_(3),TSA)were further analyzed to evaluate its atmospheric impact.Without any catalysts,the H_(2)S+SO_(3)reaction is infeasible with a barrier of 24.2 kcal/mol.Atmospheric nucleation precursors formic acid(FA),sulfuric acid(SA),and water(H_(2)O)could effectively lower the reaction barriers as catalysts,even to a barrierless reaction with the efficiency of cis-SA>trans-FA>trans-SA>H_(2)O.Subsequently,the gas-phase stability of TSA was investigated.A hydrolysis reaction barrier of up to 61.4 kcal/mol alone with an endothermic isomerization reaction barrier of 5.1 kcal/mol under the catalytic effect of SA demonstrates the sufficient stability of TSA.Furthermore,topological and kinetic analysis were conducted to determine the nucleation potential of TSA.Atmospheric clusters formed by TSA and atmospheric nucleation precursors(SA,ammonia NH_(3),and dimethylamine DMA)were thermodynamically stable.Moreover,the gradually decreasing evaporation coefficients for TSA-base clusters,particularly for TSA-DMA,suggests that TSA may participate in NPF where the concentration of base molecules are relatively higher.The present new reaction mechanismmay contributes to a better understanding of atmospheric sulfur cycle and NPF. 展开更多
关键词 New particle formation(NPF) Atmospheric sulfur cycle Nucleation process Reaction mechanism Hydrogen sulfide(H_(2)S) Atmospheric Cluster Dynamic Code (ACDC)
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Anchoring oxygen on LiNi_(0.94)Co_(0.05)Mn_(0.01)O_(2)surface by coating Ti_(x)NbB_((1−x))C_(2)boosts long-cycle stability of all-solid-state lithium batteries
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作者 Jingchi Zhang Ze Hua +6 位作者 Ziqi Wu Xinting Cao Wen Yang Ruiwen Shao Yu Bai Zhenhua Wang Kening Sun 《Journal of Energy Chemistry》 2025年第8期183-193,共11页
To satisfy the demands of modern society for high-energy–density sulfide-based all-solid-state lithium batteries(ASSLBs),Ni-rich cathode materials have gained much attention for their high capacity and energy density... To satisfy the demands of modern society for high-energy–density sulfide-based all-solid-state lithium batteries(ASSLBs),Ni-rich cathode materials have gained much attention for their high capacity and energy density.However,their practical deployment is hindered by accelerated interface degradation and capacity decay originating from surface oxygen release and lattice oxygen activation during prolonged cycling.In this study,Ti_(x)NbB_((1−x))C_(2)was successfully coated on the surface of LiNi_(0.94)Co_(0.05)Mn_(0.01)O_(2).Density functional theory(DFT)calculations first elucidate a“point-to-point”anchoring mechanism where each surface oxygen atom coordinates with single species(Ti/Nb/B)offered by Ti_(x)NbB_((1−x))C_(2),which forms robust O–M bonds and sustain a stable interface structure.The electron energy loss spectroscopy(EELS)reveals the segregation of Ti/Nb toward subsurface layers during cycling,creating an optimized lattice oxygen coordination environment and suppressing oxygen activation.The dual oxygen stabilization mechanism dramatically improves the reversibility of phase transition and the structural stability of the Ni-rich cathode materials.Moreover,Ti_(x)NbB_((1−x))C_(2)as the protective layer decreases mechanical strain and suppresses the parasitic reactions.Consequently,the engineered cathode delivers 91%capacity retention after 1000 cycles at 0.3 C,suggesting excellent cycling stability.The research delivers a new design philosophy for the coating layer that can stabilize surface oxygen.Furthermore,the atomistic understanding of the structure–property relationship of the Ni-rich cathode materials provides valuable guidance for the future design of new cathode materials with superior structural stability in ASSLBs. 展开更多
关键词 Ni-rich cathode Ti_(x)NbB_((1−x))C_(2)coating "Point-to-point"anchoring Element segregation All-solid-state lithium batteries Long cycle stability
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一种具有2-bit/cycle结构的400-MS/s 8-bit逐次逼近型模数转换器设计 被引量:1
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作者 代国宪 陈迟晓 +1 位作者 叶凡 任俊彦 《复旦学报(自然科学版)》 CAS CSCD 北大核心 2014年第4期446-451,F0002,共7页
设计了一种高速的逐次逼近型模数转换器(Successive Approximated Register Analog-Digital Converter,SAR ADC),与传统SAR ADC相比,该ADC除了采样电容阵列,额外使用了一个辅助数模转换器(Auxiliary Digital-Analog Converter,AUX-DAC)... 设计了一种高速的逐次逼近型模数转换器(Successive Approximated Register Analog-Digital Converter,SAR ADC),与传统SAR ADC相比,该ADC除了采样电容阵列,额外使用了一个辅助数模转换器(Auxiliary Digital-Analog Converter,AUX-DAC)来实现2-bit/cycle.系统设计的SAR ADC使用了一个共享的内插预放大器,可以将输入信号和比较器隔离开,减小了比较器的回踢噪声.为了进一步提高转换速度,采用比较器交替工作模式,其输出结果直接送给电容阵列进行处理,与传统SAR ADC相比大大减小了逻辑延时.由于架构中使用了多路比较器,因此采用前台校准技术用来校正比较器的失调电压.后仿结果表明该ADC在400M采样速率和1.2V的电源电压下,可以实现48dB的SNDR,功耗为5.6mW,优值FoM为67fJ/conversion-step. 展开更多
关键词 2-bit/cycle SAR ADC 内插预放大器 交替工作比较器 前台校准
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Carbon emissions in China’s steel industry from a life cycle perspective:Carbon footprint insights 被引量:4
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作者 Xiaocong Song Shuai Du +5 位作者 Chenning Deng Peng Shen Minghui Xie Ci Zhao Chen Chen Xiaoyu Liu 《Journal of Environmental Sciences》 2025年第2期650-664,共15页
China is the most important steel producer in the world,and its steel industry is one of themost carbon-intensive industries in China.Consequently,research on carbon emissions from the steel industry is crucial for Ch... China is the most important steel producer in the world,and its steel industry is one of themost carbon-intensive industries in China.Consequently,research on carbon emissions from the steel industry is crucial for China to achieve carbon neutrality and meet its sustainable global development goals.We constructed a carbon dioxide(CO_(2))emission model for China’s iron and steel industry froma life cycle perspective,conducted an empirical analysis based on data from2019,and calculated the CO_(2)emissions of the industry throughout its life cycle.Key emission reduction factors were identified using sensitivity analysis.The results demonstrated that the CO_(2)emission intensity of the steel industry was 2.33 ton CO_(2)/ton,and the production and manufacturing stages were the main sources of CO_(2)emissions,accounting for 89.84%of the total steel life-cycle emissions.Notably,fossil fuel combustion had the highest sensitivity to steel CO_(2)emissions,with a sensitivity coefficient of 0.68,reducing the amount of fossil fuel combustion by 20%and carbon emissions by 13.60%.The sensitivities of power structure optimization and scrap consumption were similar,while that of the transportation structure adjustment was the lowest,with a sensitivity coefficient of less than 0.1.Given the current strategic goals of peak carbon and carbon neutrality,it is in the best interest of the Chinese government to actively promote energy-saving and low-carbon technologies,increase the ratio of scrap steel to steelmaking,and build a new power system. 展开更多
关键词 Iron and steel industry Life cycle Carbon dioxide(CO_(2))emissions Carbon footprint China
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Multi-objective optimization and evaluation of supercritical CO_(2) Brayton cycle for nuclear power generation 被引量:4
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作者 Guo-Peng Yu Yong-Feng Cheng +1 位作者 Na Zhang Ping-Jian Ming 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期183-209,共27页
The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayto... The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear energy.Parametric analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic indexes.Results show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic performance.Among the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to optimization.The performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,respectively.The performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited funds.For the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully. 展开更多
关键词 Supercritical CO_(2)Brayton cycle Nuclear power generation Thermo-economic analysis Multi-objective optimization Decision-making methods
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Involvement of the ABA-and H_(2)O_(2)-Mediated Ascorbate-Glutathione Cycle in the Drought Stress Responses of Wheat Roots 被引量:1
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作者 Mengyuan Li Zhongye Gao +2 位作者 Lina Jiang Leishan Chen Jianhui Ma 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期329-342,共14页
Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and th... Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and the AsA–GSH cycle under drought stress in wheat has not been studied.In this study,a hydroponic experiment was conducted in wheat seedlings subjected to 15%polyethylene glycol(PEG)6000–induced dehydration.Drought stress caused the rapid accumulation of endogenous ABA and H_(2)O_(2) and significantly decreased the number of root tips compared with the control.The application of ABA significantly increased the number of root tips,whereas the application of H_(2)O_(2) markedly reduced the number of root tips,compared with that under 15%PEG-6000.In addition,drought stress markedly increased the DHA,GSH and GSSG levels,but decreased the AsA levels,AsA/DHA and GSH/GSSG ratios compared with those in the control.The activities of the four enzymes in the AsA–GSH cycle were also markedly increased under drought stress,including glutathione reductase(GR),ascorbate peroxidase(APX),monodehydroascorbate reductase(MDHAR)and dehydroascorbate reductase(DHAR),compared with those in the control.However,the application of an ABA inhibitor significantly inhibited GR,DHAR and APX activities,whereas the application of an H_(2)O_(2) inhibitor significantly inhibited DHAR and MDHAR activities.Furthermore,the application of ABA inhibitor significantly promoted the increases of H_(2)O_(2) and the application of H_(2)O_(2) inhibitor significantly blocked the increases of ABA,compared with those under 15% PEG-6000.Taken together,the results indicated that ABA and H_(2)O_(2) probably interact under drought stress in wheat;and both of them can mediate drought stress by modulating the enzymes in AsA–GSH cycle,where ABA acts as the main regulator of GR,DHAR,and APX activities,and H_(2)O_(2) acts as the main regulator of DHAR and MDHAR activities. 展开更多
关键词 ABA H_(2)O_(2) AsA-GSH cycle drought stress wheat roots
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NCAPD2 serves as a potential prognostic biomarker for lung adenocarcinoma and promotes cell proliferation,migration,invasion and cell cycle in vitro
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作者 PEILING WU LIFANG ZHAO +5 位作者 HONGYAN ZHANG YUEYAN LOU DONGFANG CHEN SHAN XUE XUEQING LIU HANDONG JIANG 《Oncology Research》 SCIE 2024年第9期1439-1452,共14页
Objectives:The pro-oncogenic effects of NCAPD2 have been extensively studied across various tumor types;however,its precise role within the context of lung adenocarcinoma(LUAD)remains elusive.This study aims to elucid... Objectives:The pro-oncogenic effects of NCAPD2 have been extensively studied across various tumor types;however,its precise role within the context of lung adenocarcinoma(LUAD)remains elusive.This study aims to elucidate the biological functions of NCAPD2 in LUAD and unravel the underlying mechanistic pathways.Methods:Utilizing bioinformatics methodologies,we explored the differential expression of NCAPD2 between normal and tumor samples,along with its correlations with clinical-pathological characteristics,survival prognosis,and immune infiltration.Results:In the TCGA-LUAD dataset,tumor samples demonstrated significantly elevated levels of NCAPD2 expression compared to normal samples(p<0.001).Clinically,higher NCAPD2 expression was notably associated with advanced T,N,and M stages,pathologic stage,gender,smoking status,and diminished overall survival(OS).Moreover,differentially expressed genes(DEGs)associated with NCAPD2 were predominantly enriched in pathways related to cell division.Immune infiltration analysis revealed that NCAPD2 expression levels were linked to the infiltration of memory B cells,naïve CD4+T cells,activated memory CD4+T cells,and M1 macrophages.In vitro experiments demonstrated that silencing NCAPD2 suppressed LUAD cell proliferation,migration,invasion,epithelial-mesenchymal transition(EMT),and cell cycle progression.Conclusions:In summary,NCAPD2 may represent a promising prognostic biomarker and novel therapeutic target for LUAD. 展开更多
关键词 NCAPD2 LUAD Prognosis Immune infiltration Cell cycle
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Mechanical response of Q_(2)loess stratum surrounding a hydraulic tunnel under dry-wet cycles
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作者 Sen Peng Caihui Zhu +5 位作者 Letian Zhai Haoding Xu Yubo Li Guohua Deng Miaomiao Ge Yuan Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第12期4955-4970,共16页
Understanding the mechanical response of Q2 loess subjected to dry-wet cycles(DWCs)is the premise for the rational design of a hydraulic tunnel.Taking the Hanjiang-to-Weihe south line project in China as the research ... Understanding the mechanical response of Q2 loess subjected to dry-wet cycles(DWCs)is the premise for the rational design of a hydraulic tunnel.Taking the Hanjiang-to-Weihe south line project in China as the research background,the microstructure evolution,strength degradation and compression characteristics of Q2 loess under different DWCs were investigated,and the fluid-solid coupling analysis of the hydraulic tunnel was carried out using the FLAC3D software.The amplification effect of tunnel surrounding soil pressure(SSP)and its influence on the long-term stability of the tunnel under different DWCs were obtained.The results showed that the pore microstructure parameters of the undisturbed and remolded loess basically tend to be stable after the number of DWCs exceeds 3.The porosity of Q2 loess is increased by 26%.The internal friction angle and cohesion of Q2 loess are decreased by 35%and 31%,respectively.The vertical strain of Q2 loess is increased by 55%after considering the DWCs.After the DWCs stabilized,the SSP ratio is increased between 10%and 25%.With the increase in buried depth of the tunnel,the SSP ratio is increased by 8%e10%.The SSP is reduced from 8%to 16%by the rise in groundwater level.As the number of DWCs increases and the burial depth of the tunnel decreases,the distribution of SSP becomes progressively more non-uniform.Based on the amplification factor and the modified compressive arch theory,the SSP distribution model of loess tunnel was proposed,which can be preliminarily applied to the design of supporting structures considering DWCs. 展开更多
关键词 Q2 loess Hydraulic tunnel Surrounding soil pressure(SSP) Dry-wet cycles(DWCs) Amplification effect
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Leucine-rich repeat-containing protein 19 suppresses colorectal cancer by targeting cyclin-dependent kinase 6/E2F1 and remodeling the immune microenvironment
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作者 Si-Si Huang Wei Chen +5 位作者 Deep K Vaishnani Li-Juan Huang Ji-Zhen Li Shi-Rui Huang Yan-Zhen Li Qi-Peng Xie 《World Journal of Gastroenterology》 2025年第25期91-121,共31页
BACKGROUND Colorectal cancer(CRC)is a leading cause of cancer-related mortality worldwide,primarily due to tumor heterogeneity and treatment resistance.The leucine-rich repeat-containing protein 19(LRRC19)has been lin... BACKGROUND Colorectal cancer(CRC)is a leading cause of cancer-related mortality worldwide,primarily due to tumor heterogeneity and treatment resistance.The leucine-rich repeat-containing protein 19(LRRC19)has been linked to immune regulation and tumor suppression,yet its specific role in CRC remains poorly understood.AIM To investigate the tumor-suppressive role of LRRC19 in CRC,focusing on cell cycle,immune microenvironment,and chemotherapy response.METHODS Bioinformatics analyses of Gene Expression Omnibus and The Cancer Genome Atlas databases identified differentially expressed genes in CRC.LRRC19 exp-ression was validated in CRC tissues and cell lines by quantitative PCR,immuno-histochemistry,and Western blotting.Functional assays,including proliferation,soft agar colony formation,flow cytometry,and xenograft models,assessed biological effects.Mechanistic studies with dual-luciferase reporter assays,molecular docking,and drug sensitivity testing explored LRRC19’s interaction with the cyclin-dependent kinase 6(CDK6)/E2F1 axis and oxaliplatin(OXA)response.Single-cell sequencing and immune infiltration analyses assessed its impact on the immune microenvironment.RESULTS LRRC19 expression was significantly downregulated in CRC and associated with poor prognosis.Overexpression of LRRC19 inhibited CRC cell proliferation,induced G0/G1 phase arrest,and suppressed tumor growth in vivo.Mechanistically,LRRC19 suppressed CDK6 transcription by downregulating E2F1,leading to cell cycle arrest.Additionally,LRRC19 promoted immune cell infiltration,particularly B cells and CD4+T cells,while decreasing immunosuppressive cells.LRRC19 also sensitized CRC cells to OXA,enhancing chemotherapy efficacy.CONCLUSION LRRC19 suppresses CRC by targeting the CDK6/E2F1 axis,modulating the immune microenvironment,and enhancing chemotherapy sensitivity,making it a promising therapeutic target for precision medicine in CRC. 展开更多
关键词 Colorectal cancer Tumor suppressor Cell cycle arrest Immune microenvironment Chemotherapy sensitivity cyclin-dependent kinase 6/E2F1 axis Oxaliplatin response Leucine-rich repeat-containing protein 19 Immune infiltration Precision medicine
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A Review on Technologies for the Use of CO2 as a Working Fluid in Refrigeration and Power Cycles
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作者 Orelien T. Boupda Hyacinthe D. Tessemo +3 位作者 Isidore B. Nkounda Fongang Francklin G. Nyami Frederic Lontsi Thomas Djiako 《Energy and Power Engineering》 2024年第6期217-256,共40页
The use of carbon dioxide as a working fluid has been the subject of extensive studies in recent years, particularly in the field of refrigeration where it is at the heart of research to replace CFC and HCFC. Its ther... The use of carbon dioxide as a working fluid has been the subject of extensive studies in recent years, particularly in the field of refrigeration where it is at the heart of research to replace CFC and HCFC. Its thermodynamic properties make it a fluid of choice in the efficient use of energy at low and medium temperatures in engine cycles. However, the performance of transcritical CO2 cycles weakens under high temperature and pressure conditions, especially in refrigeration systems;On the other hand, this disadvantage becomes rather interesting in engine cycles where CO2 can be used as an alternative to the organic working fluid in small and medium-sized electrical systems for low quality or waste heat sources. In order to improve the performance of systems operating with CO2 in the field of refrigeration and electricity production, research has made it possible to develop several concepts, of which this article deals with a review of the state of the art, followed by analyzes in-depth and critical of the various developments to the most recent modifications in these fields. Detailed discussions on the performance and technical characteristics of the different evolutions are also highlighted as well as the factors affecting the overall performance of the systems studied. Finally, perspectives on the future development of the use of CO2 in these different cycles are presented. 展开更多
关键词 Refrigeration cycle Power cycle System Performance Transcritical CO2 cycles Working Fluid
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Numerical Models and Methods of Atmospheric Parameters Originating in the Formation of the Earth’s Climatic Cycle
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作者 Wend Dolean Arsène Ilboudo Kassoum Yamba +1 位作者 Windé Nongué Daniel Koumbem Issaka Ouédraogo 《Atmospheric and Climate Sciences》 2024年第2期277-286,共10页
Atmospheric models are physical equations based on the ideal gas law. Applied to the atmosphere, this law yields equations for water, vapor (gas), ice, air, humidity, dryness, fire, and heat, thus defining the model o... Atmospheric models are physical equations based on the ideal gas law. Applied to the atmosphere, this law yields equations for water, vapor (gas), ice, air, humidity, dryness, fire, and heat, thus defining the model of key atmospheric parameters. The distribution of these parameters across the entire planet Earth is the origin of the formation of the climatic cycle, which is a normal climatic variation. To do this, the Earth is divided into eight (8) parts according to the number of key parameters to be defined in a physical representation of the model. Following this distribution, numerical models calculate the constants for the formation of water, vapor, ice, dryness, thermal energy (fire), heat, air, and humidity. These models vary in complexity depending on the indirect trigonometric direction and simplicity in the sum of neighboring models. Note that the constants obtained from the equations yield 275.156˚K (2.006˚C) for water, 273.1596˚K (0.00963˚C) for vapor, 273.1633˚K (0.0133˚C) for ice, 0.00365 in/s for atmospheric dryness, 1.996 in<sup>2</sup>/s for humidity, 2.993 in<sup>2</sup>/s for air, 1 J for thermal energy of fire, and 0.9963 J for heat. In summary, this study aims to define the main parameters and natural phenomena contributing to the modification of planetary climate. . 展开更多
关键词 Atmospheric Parameter 1 Climatic cycle 2 Numerical Models 3
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Effects of Low Dose Radiation on Tumor Apoptosis, Cell Cycle and Apoptosis-Related Protein Bcl-2 in Tumor-Bearing Mice 被引量:2
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作者 于洪升 宋爱琴 +2 位作者 费从合 王卓敏 邱文生 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第2期89-92,共4页
To study the effects of low dose radiation (LDR) on tumor apoptosis, cellcycle progression and changes of apoptosis-related protein Bcl-2 in tumor-bearing mice. Methods:Male mice of Kunming strain were implanted subcu... To study the effects of low dose radiation (LDR) on tumor apoptosis, cellcycle progression and changes of apoptosis-related protein Bcl-2 in tumor-bearing mice. Methods:Male mice of Kunming strain were implanted subcutaneously with S180 sarcoma cells in the left inguenas an in situ experimental animal model. Seven days later, the mice were subjected to 75 mGywhole-body γ-irradiation. At 24 and 48 h after the irradiation, all mice were sacrificed. The tumorsizes were measured, and tumor cell apoptosis and cell cycle progression were analyzed by flowcytometry. The expression of apoptosis-related protein Bcl-2 and the apoptotic rate of tumor cellswere observed by immunohistochemistry and electron microscopy. Results: Tumors grew significantlyslower after LDR (P 【 0.05). The tumor cells were arrested in G1 phrase and the expression of Bcl-2protein decreased at 24 h. Apoptotic rate of tumor cells was increased significantly at 48 h afterLDR (P 【 0.01). Conclusion: LDR could cause a G1-phase arrest and increase the apoptosis of tumorcells through the low level of apoptosis-related protein bcl-2 in the tumor-bearing mice. Theorganized immune function and anti-tumor ability are markedly increased after LDR. Our studyprovides practical evidence of clinical application to cancer treatment. 展开更多
关键词 low dose radiation S180 sarcoma APOPTOSIS cell cycle BCL-2
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CO_(2)-ESGR技术全生命周期碳排放分析 被引量:1
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作者 周军平 董志强 +5 位作者 鲜学福 旷年杰 徐程浩 彭毅凡 李森圣 薛元杰 《天然气工业》 北大核心 2025年第1期195-206,共12页
在页岩气井开采后期,将CO_(2)注入页岩气藏可在提高页岩气采收率的同时实现CO_(2)地质封存(CO_(2)-ESGR),但目前对于CO_(2)-ESGR技术减碳潜力尚缺乏从全生命周期角度进行的研究。为此,分别以重庆市双槐电厂、涪陵页岩气田作为CO_(2)源和... 在页岩气井开采后期,将CO_(2)注入页岩气藏可在提高页岩气采收率的同时实现CO_(2)地质封存(CO_(2)-ESGR),但目前对于CO_(2)-ESGR技术减碳潜力尚缺乏从全生命周期角度进行的研究。为此,分别以重庆市双槐电厂、涪陵页岩气田作为CO_(2)源和汇,采用全生命周期评价方法,建立了CO_(2)-ESGR技术全过程CO_(2)排放量核算模型,进而基于多场耦合作用下CO_(2)、CH_(4)渗流数学模型得到了CO_(2)封存量及页岩气产量,并系统核算了CO_(2)-ESGR全过程CO_(2)排放量,分析了CO_(2)注入压力、页岩中CO_(2)相对CH_(4)的吸附选择性系数(α_(CO_(2)/CH_(4)))等参数对CO_(2)净减排量的影响。研究结果表明:①CO_(2)注入压力和α_(CO_(2)/CH_(4))对于CO_(2)净减排量具有重要影响,α_(CO_(2)/CH_(4))越大,CO_(2)净减排量越大,CO_(2)注入压力增加,CH_(4)累计产量、CO_(2)封存量、CO_(2)净减排量均越大,不同CO_(2)注入压力条件下CO_(2)净减排量为0.85~2.06 tCO_(2)/tCH_(4),而在不同α_(CO_(2)/CH_(4))条件下可达1.59~5.45 tCO_(2)/tCH_(4);②CO_(2)捕集、运输、注入环节是影响CO_(2)-ESGR技术全生命周期CO_(2)净减排量的关键因素,需要考虑不同行业组合、源汇匹配情况对CO_(2)净减排量的影响,进而对全流程CCUS工程实施方案进行优化。结论认为:①该CO_(2)-ESGR工程CO_(2)封存量大于CO_(2)捕集、运输、注入及页岩气生产与利用环节的CO_(2)总排放量,可实现CO_(2)-ESGR全过程CO_(2)负排放,说明CO_(2)-ESGR是实现中国“碳中和”的重要技术路径之一;②下一步研究应综合考虑CO_(2)注入时机、压力、速率等工程参数以及页岩气储层条件等地质因素对于CO_(2)封存量和净减排量的影响,对CO_(2)-ESGR系统进行优化。 展开更多
关键词 页岩气 CCUS CO_(2)封存潜力 碳中和 全生命周期评价 CO_(2)-ESGR CO_(2)净减排
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Expressions of MMP-2,-9,TIMP-1,-2,-3 mRNA in Rat Uterus during Estrous Cycle 被引量:1
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作者 赵云阁 曹秀梅 +1 位作者 肖爱珍 祝诚 《Developmental and Reproductive Biology》 1999年第2期1-10,共10页
Zymography and in situ hybridization were used to investigate matrixmetalloproteinase -2, -9 (MMP -2, MMP-9) activities and expressions of MMP -2, -9 and TIMP1, -2, -3 (tissue inhibitors of matrix metallo-proteinases)... Zymography and in situ hybridization were used to investigate matrixmetalloproteinase -2, -9 (MMP -2, MMP-9) activities and expressions of MMP -2, -9 and TIMP1, -2, -3 (tissue inhibitors of matrix metallo-proteinases) mRNA in the rat uterus during estrouscycle. The relative activity was semiquanted by using densitometric analysis. The MMP-2(67 kDa) activity in every stage during estrpus cycle was detected by zymography. MMP-2activity was highest at proestrus; higher at estrus and metaestrus; lowest at diestrus. Throughin situ hybridization, MMP -2, -9, TIMP -1~ -3 mRNA mainly in hasal stroma cells of uterineendometrium were detected. The positive signals of MMP -2 and -9 mRNAs in hasal stromacells were shown stronger at proestrus, estrus and metaestrus while they showed the weakest atdiestrus. The expression of MMP -2 mRNA coincided with MMP -2 activity change. MMP-2and -9 mRNAs were also highly expressed in uterine circular muscle at estrus. Weak signals ofMMP -9 mRNA were detected in uterine luminal and glandular epithelial cells at estrus.TIMP -1 mRNA in hasal stroma cells was shown as the strongest expression at estrus andmetaestrus; stronger at proestrus and the weakest at diestrus. TIMP-2 mRNA in basal stromacells was stronger at estrus and diestrus; weaker at proestrus and metaestrus. TIMP -1 and -2mRNAs were also highly expressed in uterine luminal and glandular epithelial cells at estrus.TIMP -3 mRNA in hasal stroma cells revealed the strongest expression at estrus; stronger atdiestrus and metaestrus and showed the weakest at proestrus. The mRNA was also highlyexpressed in uterine circular muscle at estrus. In short, our present results provide evidencethat MMP -2, -9 and TIMP -1~ -3 were involved in rat uterine endometrium reconstructionduring estrous cycle. 展开更多
关键词 MMP -2 -9 TIMP-1 -2 and -3 activity gene expression estrous cycle rat UTERUS
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α-Fe_(2)O_(3)/还原氧化石墨烯(RGO)的制备及应用
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作者 王宏智 包赛赛 +2 位作者 苏展 于金山 张卫国 《化学工业与工程》 北大核心 2025年第1期88-97,共10页
为实现非对称超级电容器(ASC)的高电化学性能,以FeCl_(3)·6H_(2)O为铁源,通过水热法将α-Fe_(2)O_(3)纳米颗粒均匀分散在还原的氧化石墨烯(RGO)薄片上,成功制备α-Fe_(2)O_(3)/RGO复合材料。该复合材料采用SEM、TEM、XRD和XPS进行... 为实现非对称超级电容器(ASC)的高电化学性能,以FeCl_(3)·6H_(2)O为铁源,通过水热法将α-Fe_(2)O_(3)纳米颗粒均匀分散在还原的氧化石墨烯(RGO)薄片上,成功制备α-Fe_(2)O_(3)/RGO复合材料。该复合材料采用SEM、TEM、XRD和XPS进行表征,并利用标准三电极体系进行电化学性能测试。结果显示:高度组装的α-Fe_(2)O_(3)/RGO在1 A·g^(-1)下具有740.8 F·g^(-1)的大比电容,并且于5 A·g^(-1)下实现80.0%的长循环稳定性(10000圈)。以制备的α-Fe_(2)O_(3)/RGO为负极,NiCo_(2)O_(4)为正极组装了NiCo_(2)O_(4)//α-Fe_(2)O_(3)/RGO非对称超级电容器,不仅在792.8 W·kg^(-1)下获得47.8 Wh·kg^(-1)的能量密度,而且在5 A·g^(-1)下仍然维持78.6%的循环稳定性(10000圈)。这极大地促进了ASC在储能系统的应用。 展开更多
关键词 α-Fe_(2)O_(3) 石墨烯 非对称超级电容器 循环性能
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面向新型电力系统的S-CO_(2)循环发电技术进展
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作者 李红智 张一帆 +6 位作者 白文刚 杨玉 李凯伦 周毓佳 孙山 张旭伟 倪依柯 《中国电机工程学报》 北大核心 2025年第14期5342-5357,I0001,共17页
超临界二氧化碳(supercritical CO_(2),S-CO_(2))循环发电是以CO_(2)为工质、整个循环系统均在CO_(2)临界点以上运行的新型动力循环发电技术,具有高参数效率高、全负荷灵活性好、机组占地面积小和热源适用性广等优点,是国内外普遍认可... 超临界二氧化碳(supercritical CO_(2),S-CO_(2))循环发电是以CO_(2)为工质、整个循环系统均在CO_(2)临界点以上运行的新型动力循环发电技术,具有高参数效率高、全负荷灵活性好、机组占地面积小和热源适用性广等优点,是国内外普遍认可的变革性热力发电技术。该技术在高效灵活火电、高参数光热发电和液态金属小型核电等应用领域,相比传统蒸汽动力循环更具优势,对我国构建新型电力系统意义重大。该文重点分析S-CO_(2)循环系统构建、核心设备设计、动态仿真和运行控制等关键技术国内外的最新研究进展及下一步亟待解决的技术难点,可为S-CO_(2)循环发电的技术迭代和示范应用提供一定参考。 展开更多
关键词 超临界二氧化碳动力循环 循环构建 新型换热设备 旋转机械 运行控制策略 新型电力系统
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带喷射器的跨临界CO_(2)热泵系统动态特性研究
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作者 徐肖肖 何智梅 +2 位作者 郝云樱 张申 骆名文 《天津大学学报(自然科学与工程技术版)》 北大核心 2025年第9期914-922,共9页
带喷射器的跨临界CO_(2)热泵循环系统由两个耦合子循环组成,具有高度非线性特性,且喷射器对工况变化敏感,独特的热力学行为导致该系统动态响应较为复杂.针对上述问题,建立带喷射器的跨临界CO_(2)热泵系统的动态模型,模型中换热器采用有... 带喷射器的跨临界CO_(2)热泵循环系统由两个耦合子循环组成,具有高度非线性特性,且喷射器对工况变化敏感,独特的热力学行为导致该系统动态响应较为复杂.针对上述问题,建立带喷射器的跨临界CO_(2)热泵系统的动态模型,模型中换热器采用有限体积法构建空间离散化模型,喷射器采用基于实际气体的计算模型.并对该动态模型进行了验证,稳定后的模拟结果与实验数据基本吻合,其误差小于5%.通过MATLAB/Simulink求解计算,研究了内部参数(蒸发温度)及外部参数(冷却水流量)阶跃变化扰动下的系统各参数的动态响应.结果表明,相较于外部参数变化引起的动态响应,系统对内部参数的变化更为敏感,且响应初期系统压力出现逆向响应现象.当内部参数蒸发温度降低时喷射系数快速降低后达到稳定,升压比在蒸发温度较低时波动较大,随着蒸发温度提高,波动较小.蒸发温度从-0.45℃降至-4.80℃,喷射系数较初始工况降幅可达45.95%.而外部参数(冷却水流量)阶跃变化扰动对系统的制热系数(COPh)影响更为明显,当外部参数(冷却水流量)增加时,系统压力均下降,喷射系数总体呈下降趋势,系统制热系数增加.冷却水流量从3.3 L/min增至4.6 L/min时,系统制热系数增幅达13.86%.系统各部分耦合作用强烈,在相同操作工况下模型趋于稳定后的结果与实验结果的趋势一致,为改进带喷射器的跨临界CO_(2)热泵系统控制策略、增强系统稳定性奠定基础. 展开更多
关键词 喷射器 CO_(2) 跨临界热泵循环 动态特性
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