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一种带有比较器交错的2-bit/cycle高速SAR ADC
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作者 费秘 岳宏卫 韦善于 《微电子学》 北大核心 2025年第6期941-948,共8页
针对传统2-bit/cycle逐次逼近模数转换器(SAR ADC)中需要2^(N)个额外单位电容来提高速度的问题,基于CMOS 40 nm工艺提出了一种带有比较器交错的2-bit/cycle高速SAR ADC。该结构通过在最后一个比较周期自动切换不同尺寸大小的比较器来等... 针对传统2-bit/cycle逐次逼近模数转换器(SAR ADC)中需要2^(N)个额外单位电容来提高速度的问题,基于CMOS 40 nm工艺提出了一种带有比较器交错的2-bit/cycle高速SAR ADC。该结构通过在最后一个比较周期自动切换不同尺寸大小的比较器来等效减小参考电压的方法,将电容式数模转换器(CDAC)单位电容的使用量降低50%。此外,提出的比较器速度反馈系统能够在输入电压差较低时提高比较器的速度,并通过在采样保持电路中采用两段栅压自举和引入补偿电容的方法来降低噪声与失真。仿真结果表明,该ADC的分辨率为10 bit,采样频率为700 MS/s,在Nyquist输入频率下的SNDR为55.05 dB,SFDR为67.27 dB,整体功耗为2.91 mW,Walden FoM为9.20 fJ/conv.。 展开更多
关键词 2-bit/cycle 速度反馈 高速 SAR ADC 比较器交错
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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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Oxygen-Pressure Protocol Breaking Cycle Limit of Continuously Reversible Lithium-Oxygen Batteries
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作者 Xinhang Cui Fenglong Xiao +10 位作者 Guoliang Zhang Zhangliu Tian Qingshan Bao Yanlu Li Deliang Cui Qilong Wang Feng Dang Wei Chen Haohai Yu Huaijin Zhang Gang Lian 《Nano-Micro Letters》 2026年第5期391-404,共14页
Lithium-oxygen(Li-O_(2))battery is favored among“beyond lithiumion”technologies for sustainability because of its exceptional energy density.Major impediments are the poor cycle stability and grievous capacity degra... Lithium-oxygen(Li-O_(2))battery is favored among“beyond lithiumion”technologies for sustainability because of its exceptional energy density.Major impediments are the poor cycle stability and grievous capacity degradation at high current densities.We address these issues by a“killing two birds with one stone”O_(2)-pressure protocol.It first resolves efficient O_(2) mass transport at high rates..The accelerated reaction kinetics optimizes the composition and growth pathway of discharge products.This protocol secondly achieves protection of Li anodes via densifying corrosion layers on them.Consequently,the battery delivers both ultrahigh discharge capacity(>9,000 mAh g^(-1))at 3,000 mA g^(-1) and excellent cycling stability.Under a dual-strategy effect of high-pressure O_(2) and artificial protection layers,the battery actualizes over 11-fold increase in cycle life of 5,170 h(2,585 cycles).The strategy opens avenues for advancing Li-O_(2) batteries towards practical application and confers the extension to other gas-based batteries. 展开更多
关键词 Li-O_(2)batteries O_(2)pressure cycle life Li anode protection Rate performance
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p53、CyclinD1和MDM2在浸润性乳腺癌中的表达及临床意义
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作者 姚丽平 陈见昂 +3 位作者 王培珍 李玟 陈建荣 胡孟钧 《浙江医学》 2026年第1期26-31,共6页
目的探讨p53、细胞周期蛋白D1(CyclinD1)和双微体2(MDM2)在浸润性乳腺癌(IBC)中的表达情况及临床意义。方法回顾性收集2015年3月至2017年2月在温州医科大学附属第一医院经手术切除的原发性IBC组织石蜡标本111例及配对的癌旁组织石蜡标... 目的探讨p53、细胞周期蛋白D1(CyclinD1)和双微体2(MDM2)在浸润性乳腺癌(IBC)中的表达情况及临床意义。方法回顾性收集2015年3月至2017年2月在温州医科大学附属第一医院经手术切除的原发性IBC组织石蜡标本111例及配对的癌旁组织石蜡标本64例(47例无配对的癌旁组织),并收集记录患者详细的临床资料。采用组织微阵列结合免疫组化技术检测p53、CyclinD1和MDM2在癌组织及对应癌旁组织中的表达水平。分析这3种蛋白与临床病理特征和预后的关系。结果IBC组织p53、CyclinD1和MDM2表达阳性率均明显高于癌旁组织(P<0.05)。TNM分期Ⅲ~Ⅳ期、组织学分级Ⅱ~Ⅲ级、有脉管侵犯和淋巴结转移的患者IBC组织p53表达阳性率分别高于TNM分期Ⅰ~Ⅱ期、组织学分级Ⅰ级、无脉管侵犯和无淋巴结转移的患者(均P<0.05)。无淋巴结转移、雌激素受体(ER)阳性和孕激素受体(PR)阳性的患者IBC组织CyclinD1表达阳性率分别高于有淋巴结转移、ER阴性和PR阴性的患者(均P<0.05)。ER阳性、PR阳性的患者IBC组织MDM2表达阳性率分别高于ER阴性、PR阴性的患者(均P<0.05)。Cox回归分析显示,IBC组织MDM2表达阳性及CyclinD1表达阴性均是患者未达到3年无病生存时间的危险因素(均P<0.05)。结论p53、CyclinD1和MDM2在IBC组织中表达上调;MDM2表达上调是IBC患者预后不良的危险因素;CyclinD1表达上调是IBC患者预后良好的保护因素。 展开更多
关键词 浸润性乳腺癌 P53 细胞周期蛋白D1 双微体2 预后
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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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CMC-Zn hydrogel electrolyte with self-releasing Zn^(2+)achieves long cycle stability in aqueous zinc ion batteries
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作者 Nannan Zhong Ning Cao +5 位作者 Xinhui Chi Lin Yang Liya A Boyuan Liu Jingyi Guan Xiaobei Zang 《Energy Materials and Devices》 2025年第4期80-92,共13页
Zinc-ion batteries(ZIBs)have garnered significant interest owing to their intrinsic safety,environmental compatibility,and low cost.However,nonuniform Zn deposition and parasitic side reactions during cycling lead to ... Zinc-ion batteries(ZIBs)have garnered significant interest owing to their intrinsic safety,environmental compatibility,and low cost.However,nonuniform Zn deposition and parasitic side reactions during cycling lead to rapid capacity decay and potential short-circuiting.To address these challenges,we developed a carboxymethyl cellulose-zinc(CMC-Zn)hydrogel electrolyte with self-release capability using a metal-ion crosslinking approach.The dynamically reversible CMC-Zn network continuously supplies active Zn^(2+)during cycling,compensating for electrode consumption in real time.Abundant carboxylate and hydroxyl groups regulate uniform zinc nucleation and growth,while the hydrogen-bonding network synergistically suppresses side reactions,as reflected by a low hydrogen-evolution potential(−0.281 V)and reduced corrosion current density(0.03 mA cm^(−2)).With these advantages,Zn||Zn symmetric cells achieve an ultralong lifespan of 6,400 h at 0.5 mA cm^(−2),and Zn||Cu half-cells deliver a stable coulombic efficiency of 99.1%over 4,200 cycles.In fullcell testing,self-released Zn^(2+)contributes 29%of the overall capacity,enabling Zn||PANI cells to retain 75%capacity after 2,000 cycles and exhibit a rate-performance recovery of 97.4%.A corresponding flexible ZIB maintains stable operation under various deformation conditions,highlighting the strong potential of CMC-Zn hydrogel electrolytes for next-generation flexible energy-storage devices. 展开更多
关键词 CMC-Zn hydrogel self-releasing Zn^(2+) long cycle life aqueous zinc-ion battery
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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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Life Cycle Assessment of Solar-Assisted Post-Combustion CO_(2) Capture Using Hollow Fiber Membrane Contactors
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作者 Lei Wang Hongyang Zhou +5 位作者 Xiaofan Liu Junkun Mu Jinpeng Bi Youkang Jin Juan Ge Yuexia Lv 《Frontiers in Heat and Mass Transfer》 2025年第6期1811-1832,共22页
Membrane gas absorption and solar-assisted absorbent regeneration offer a sustainable approach to reduce the energy penalty of post-combustion CO_(2) capture.This study introduces a novel system integrating solar ther... Membrane gas absorption and solar-assisted absorbent regeneration offer a sustainable approach to reduce the energy penalty of post-combustion CO_(2) capture.This study introduces a novel system integrating solar thermal energy with membrane gas absorption to capture CO_(2) from a 580 MWe pulverized coal power plant.The environmental impacts across six scenarios at varying solar fractions are evaluated via life cycle assessment.Results show a 7.61%–13.04%reduction in global warming potential compared to a steam-driven CO_(2) capture system.Electricity and steam consumption dominate the operational phase,contributing 15%–64%and 18%–61%to environmental impacts in non-TES scenarios,respectively.While TES reduces most impacts,it increases stratospheric ozone depletion and marine eutrophication due to nitrate-based phase change materials and monoethanolamine.Higher solar fractions lower impacts in non-TES scenarios but elevate specific impacts in TES scenarios,highlighting trade-offs for sustainable CO_(2) capture deployment. 展开更多
关键词 Solar-assisted CO_(2)capture membrane gas absorption life cycle assessment thermal energy storage
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Catalytic Cracking of Crude Palm Oil-Based Biorefinery to Biogasoline overγ-Al_(2)O_(3):Study of Physico-Chemical Properties and Life Cycle Assessment
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作者 Hosta Ardhyananta Widyastuti Widyastuti +7 位作者 Maria Anityasari Sigit Tri Wicaksono Vania Mitha Pratiwi Rindang Fajarin Liyana Labiba Zulfa Komang Nickita Sari Ninik Safrida Haris Al Hamdi 《Journal of Renewable Materials》 2025年第10期1913-1934,共22页
The total replacement of old fossil fuels poses obstacles,making the production of efficient biogasoline vital.Despite its potential as an environmentally friendly fossil fuel substitute,the life cycle assessment(LCA)... The total replacement of old fossil fuels poses obstacles,making the production of efficient biogasoline vital.Despite its potential as an environmentally friendly fossil fuel substitute,the life cycle assessment(LCA)of palm oil-derived biogasoline remains underexplored.This study investigated the production of biogasoline fromcrude palm oil(CPO)based biorefinery using catalytic cracking over mesoporousγ-Al_(2)O_(3) catalyst and LCA analysis.High selectivity of converting CPO into biogasoline was achieved by optimizing catalytic cracking parameters,including catalyst dose,temperature,and contact time.γ-Al_(2)O_(3) and CPO were characterized by several methods to study the physical and chemical properties.The physical properties of biogasoline,such as density,calorific value,viscosity,and flash point,were investigated.An overall yield of 60.11%was achieved after catalytic cracking produced several C5-C11 short-chain hydrocarbons.Additionally,this research proposes innovative emission reduction strategies,including waste-to-biogasoline conversion and the use of biodegradable feedstocks that enhance the sustainability of biogasoline production.LCA ofγ-Al_(2)O_(3)’s energy and environmental implications reveals minor effects on global warming(0.0068%)and freshwater ecotoxicity(0.187%).LCAs show a 0.085%impact in the energy sector.This focus on both ecological impacts and practical mitigation strategies deepens the understanding of biogasoline production. 展开更多
关键词 Catalytic cracking crude palm oil biogasoline γ-Al_(2)O_(3) life cycle assessment
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Unravelling the electrochemical evolution mechanism of In_(2)O_(3) anode in long-cycle all-solid-state lithium batteries with sulfide electrolytes
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作者 Wan-Ping Liu Jun Liu +6 位作者 Xue-Lei Li Qing-Wen Li Zhi-Hui Xu Hui-Rong Liu Jia-Feng Cao Aruuhan Bayaguud Hexi Baoyin 《Rare Metals》 2025年第7期4582-4594,共13页
In sulfide-based all-solid-state lithium batteries(ASLBs),the development of high-capacity anode materials with stable interfaces to sulfide solid-state electrolytes(SSEs)is critical.Here,In_(2)O_(3)is explored as an ... In sulfide-based all-solid-state lithium batteries(ASLBs),the development of high-capacity anode materials with stable interfaces to sulfide solid-state electrolytes(SSEs)is critical.Here,In_(2)O_(3)is explored as an anode material for ASLBs for the first time,demonstrating exceptional interfacial stability and electrochemical performance.The In_(2)O_(3)anode,with a substantial mass loading of 7.64 mg cm^(-2),sustains a charge-specific capacity of528.0 mAh g^(-1)(4.03 mAh cm^(-2))at a current density of0.76 mA cm^(-2)over 500 cycles,with a capacity retention of 81.2%.Additionally,it exhibits remarkable long-term cycling stability(2900 cycles)under a high current density of 3.82 mA cm^(-2),with an exceptionally low decay rate of0.016%per cycle.The charge-discharge mechanism of the In_(2)O_(3)anode is elucidated in detail,revealing that the electrochemical evolution of In_(2)O_(3)in ASLBs involves notonly the alloying/dealloying process of indium(In)but also a conversion reaction between In and Li_(2)O.Notably,as cycling progresses,the conversion reaction of In and Li_(2)O diminishes,with the reversible alloy ing/dealloy ing process becoming predominant.This work offers valuable insights for advancing oxide anode materials in sulfide-based ASLBs. 展开更多
关键词 All-solid-state lithium batteries Sulfide solid-state electrolytes In_(2)O_(3)anode Long-term cycling Charge-discharge mechanism
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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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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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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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联合循环燃气轮机系统中低浓度CO_(2)捕集的双相吸收剂研究
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作者 于航 金理健 +3 位作者 孔思凝 张帆 何梓睿 杨林军 《中国电机工程学报》 北大核心 2026年第4期1530-1541,I0019,共13页
针对燃气轮机联合循环系统(combined-cycle gas turbine,CCGT)排放烟气中低浓度CO_(2)捕集效率低、能耗高的问题,该文开发一种基于3-二甲胺基丙胺(dimethylaminopropylamine,DMPDA)/N,N-二甲基环己胺(dimethylcyclohexylamine,DMCA)/H_(... 针对燃气轮机联合循环系统(combined-cycle gas turbine,CCGT)排放烟气中低浓度CO_(2)捕集效率低、能耗高的问题,该文开发一种基于3-二甲胺基丙胺(dimethylaminopropylamine,DMPDA)/N,N-二甲基环己胺(dimethylcyclohexylamine,DMCA)/H_(2)O体系的新型两相吸收剂。通过鼓泡反应器实验结合碳-13核磁共振(carbon-13 nuclear magnetic resonance,13C NMR)表征和量子化学计算,系统研究吸收剂的CO_(2)捕集性能、分相特性及反应机理。结果表明,当吸收剂组成为30 wt.%DMPDA且DMCA与H_(2)O质量比为6:4(DDH364)时,在313 K条件下CO_(2)吸收容量可达2.28 mol/kg,383 K解吸后循环容量达1.96 mol/kg;吸收后溶液自发分相,富相占比48%且黏度仅为44.6 mPa×s;反应后富相中的产物主要为DMPDACOO-,在质子化反应过程中,质子转移优先发生在分子内部;再生能耗低至2.74 GJ/tCO_(2),较传统30 %单乙醇胺(monoethanolamine,MEA)吸收剂降低38%。研究表明,DMPDA/DMCA/H_(2)O两相吸收剂具有吸收速率快、黏度低、再生能耗少等优势,可为CCGT系统低浓度CO_(2)高效捕集提供新型解决方案。 展开更多
关键词 CO_(2)捕集 燃气轮机联合循环 低浓度CO_(2) 两相吸收剂 再生能耗
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一种具有噪声整形功能的2bit/cycle SAR ADC的设计 被引量:2
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作者 陈志铭 高一格 +1 位作者 张蕾 王兴华 《北京理工大学学报》 EI CAS CSCD 北大核心 2022年第5期536-542,共7页
基于180nm CMOS工艺,设计了一种2 bit/cycle结构的8 bit、100 MS/s逐次逼近模数转换器(SAR ADC).采用两个DAC电容阵列SIG_DAC、REF_DAC实现了2 bit/cycle量化,其中SIG_DAC采用上极板采样大大减少了电容数目,分裂电容式结构和优化的异步... 基于180nm CMOS工艺,设计了一种2 bit/cycle结构的8 bit、100 MS/s逐次逼近模数转换器(SAR ADC).采用两个DAC电容阵列SIG_DAC、REF_DAC实现了2 bit/cycle量化,其中SIG_DAC采用上极板采样大大减少了电容数目,分裂电容式结构和优化的异步SAR逻辑提高了ADC的转换速度.应用一种噪声整形技术,有效提高了过采样时ADC的信噪失真比(SNDR).在1.8 V电源电压和100 MS/s采样率条件下,未加入噪声整形时,仿真得到ADC的SNDR为46.22 dB,加入噪声整形后,过采样率为10时,仿真得到的SNDR为57.49 dB,提高了11.27 dB,ADC的有效位数提高了约1.88 bit,达到9.26 bit. 展开更多
关键词 2 bit/cycle 逐次逼近型模数转换器 噪声整形
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跨临界CO_(2)驻车热泵空调最优排气压力研究
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作者 刘业凤 钟海辉 +3 位作者 罗志鹏 李洁 丁民淅 张华 《暖通空调》 2026年第3期86-90,65,共6页
以带回热器的跨临界CO_(2)热泵空调系统为基础,设计搭建了跨临界CO_(2)驻车热泵空调系统实验台,通过控制车内回风温度、压缩机频率和车内送风量等参数,研究了跨临界CO_(2)驻车热泵空调的最优排气压力。结果表明:跨临界CO_(2)系统对欠排... 以带回热器的跨临界CO_(2)热泵空调系统为基础,设计搭建了跨临界CO_(2)驻车热泵空调系统实验台,通过控制车内回风温度、压缩机频率和车内送风量等参数,研究了跨临界CO_(2)驻车热泵空调的最优排气压力。结果表明:跨临界CO_(2)系统对欠排气压力更为敏感,当车外环境温度为7℃,车内回风温度为20℃,车内、外风量分别为400 m^(3)/h和1000 m^(3)/h时,系统最优排气压力为7.77 MPa,该工况下将系统排气压力从7.42 MPa升至7.77 MPa,系统COP提升了1.1,而随着排气压力从7.77 MPa继续升高至9.41 MPa,COP仅下降了0.3;增大车内送风量可有效降低气冷器出口温度和最优排气压力,当车内送风量从300 m^(3)/h增大到400 m^(3)/h时,气冷器出口温度下降4℃,最优排气压力降低1.15 MPa;气冷器出口温度对最优排气压力的影响最为显著,当系统运行工况改变时,这2个参数总是同步变化;基于试验数据拟合了一个新的最优排气压力预测关联式,该关联式预测值与试验值的最大偏差仅为3.5%,准确性较高,可为跨临界CO_(2)热泵空调系统排气压力的控制提供参考,确保系统始终在最佳COP下运行。 展开更多
关键词 跨临界CO_(2)循环 热泵 驻车空调 最优排气压力 COP 关联式 气冷器出口温度
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Regulation of the cell cycle gene, BTG2, by miR-21 in human laryngeal carcinoma 被引量:41
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作者 Min Liu Haidong Wu Tao Liu Yixuan Li Fang Wang Haiying Wan Xin Li Hua Tang 《Cell Research》 SCIE CAS CSCD 2009年第7期828-837,共10页
MicroRNAs are short regulatory RNAs that negatively modulate gene expression at the post-transcriptional level, and are deeply involved in the pathogenesis of several types of cancers. To investigate whether specific ... MicroRNAs are short regulatory RNAs that negatively modulate gene expression at the post-transcriptional level, and are deeply involved in the pathogenesis of several types of cancers. To investigate whether specific miRNAs and their target genes participate in the molecular pathogenesis of laryngeal carcinoma, oligonucleotide microarrays were used to assess the differential expression profiles of microRNAs and mRNAs in laryngeal carcinoma tissues compared with normal tissues. The oncogeuic miRNA, microRNA-21 (miR-21), was found to he npregulated in laryngeal carcinoma tissues. Knockdown of miR-21 by specific antisense oligonucleotides inhibited the proliferation potential of HEp-2 cells, whereas overexpression of miR-21 elevated growth activity of the cells, as detected by the colony formation assay. The cell number reduction caused by miR-21 inhibition was due to the loss of control of the G1-S phase transition, instead of a noticeable increase in apoptosis. Subsequently, a new target gene of miR- 21, BTG2, was found to be downregulated in laryngeal carcinoma tissues. BTG2 is known to act as a pan-cell cycle regulator and tumor suppressor. These findings indicate that aberrant expression of miR-21 may contribute to the malignant phenotype of laryngeal carcinoma by maintaining a low level of BTG2. The identification of the oneogenic miR-21 and its target gene, BTG2, in laryngeal carcinoma is potentially valuable for cancer diagnosis and therapy. 展开更多
关键词 MICRORNA cell cycle BTG2 laryngeal carcinoma MICRORNA-21
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Carbon emissions in China’s steel industry from a life cycle perspective:Carbon footprint insights 被引量:9
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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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