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Modeling and analysis of a novel oxygen production approach with full-spectrum solar energy for the lunar human base
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作者 Wei Zhu Maobin Hu 《中国科学技术大学学报》 北大核心 2025年第2期2-17,1,I0001,共18页
Building a lunar human base is one of the important goals of human lunar exploration.This paper proposes a method for the production of oxygen by combining photothermal synergistic water decomposition with high-temper... Building a lunar human base is one of the important goals of human lunar exploration.This paper proposes a method for the production of oxygen by combining photothermal synergistic water decomposition with high-temperature carbon dioxide electrolysis,utilizing the full solar spectrum.The optimal oxygen production rates under different solid oxide electrolysis cell inlet temperatures T_(e),ultraviolet(UV)separation wavelengths λ_(2),infrared(IR)separation wavelengths,and photovoltaic cell materials were explored.The results indicate that the inlet temperature of the solid oxide electrolysis cell should be as high as possible so that more carbon dioxide can be converted into carbon monoxide and oxygen.Furthermore,when the ultraviolet separation wavelength is approximately 385 nm,the proportion of solar energy allocated to the photoreaction and electrolysis cell is optimal,and the oxygen production rate is highest at 2.754×10^(-4) mol/s.Moreover,the infrared separation wavelength should be increased as much as possible within the allowable range to increase the amount of solar radiation allocated to the electrolysis cell to improve the rate of oxygen generation.In addition,copper indium gallium selenide(CIGS)has a relatively large separation wavelength,which can result in a high oxygen production rate of 3.560×10^(-4) mol/s.The proposed integrated oxygen production method can provide a feasible solution for supplying oxygen to a lunar human base. 展开更多
关键词 lunar oxygen production full-spectrum solar energy photovoltaic and photon-enhanced thermionic emission electrolysis of carbon dioxide photothermal synergistic reaction solid oxide electrolysis cell
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The association between daily temperature extremes and human biomarkers:heterogeneous effects of occupation and season
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作者 Yang Zhao Chunmei Yang +3 位作者 Yina Li Haiou Hong Rui Wang Jiuchang Wei 《中国科学技术大学学报》 北大核心 2025年第3期53-66,52,I0002,共16页
The impact of extreme temperatures on the health of individuals in different organizations remains uncertain.We employed stratified analyses to examine the impacts of summer(April-September)daily maximum temperatures ... The impact of extreme temperatures on the health of individuals in different organizations remains uncertain.We employed stratified analyses to examine the impacts of summer(April-September)daily maximum temperatures and winter(October-March)daily minimum temperatures on blood pressure and lipid profiles across government staff,com-pany employees,and researchers.We examined 209,477 physical examination records from a physical examination center in the First Affiliated Hospital of USTC from 2017 to 2021.Employing a segmented regression model within the frame-work of generalized linear regression(GLM),we examined the causal impact of extreme temperatures on health outcomes.Additionally,sensitivity analyses were conducted via distributed lag nonlinear models(DLNMs),with a focus on ob-serving the long-term effects over a period of 21 days.Our findings indicate that government staff face increased health risks during extremely low temperatures,regardless of the season.Compared with participants experiencing median tem-peratures,government staff exposed to extremely low temperatures(below the 10th percentile,below 24℃)in the sum-mer presented maximum increases of 2.32 mmHg(95%CI:1.542-3.098)in diastolic blood pressure and 6.481 mmHg(95%CI:5.368-7.594)in systolic blood pressure.In winter,government staff exposed to temperatures below the 10th per-centile(below 1℃)demonstrated maximum increases of 0.278 mmol/L(95%CI:0.210-0.346)in total cholesterol,0.153 mmol/L(95%CI:0.032-0.274)in triglycerides,and 0.077 mmol/L(95%CI:0.192-0.134)in low-density lipoprotein.Conversely,warm winters benefit company employees,whereas researchers exhibit lower sensitivity to temperature changes in winter.The maximum temperatures in summer and minimum temperatures in winter had greater impacts on in-dividuals.Small temperature fluctuations impact health more than large changes do.Notably,both the maximum and min-imum temperatures were better predictors of health outcomes than the daily average temperature was.Blood pressure con-sistently displayed significant associations with temperature across all three groups,with extremely low temperatures in-creasing the risk and extremely high temperatures reducing it.However,the relationship between temperature and blood lipids is complex. 展开更多
关键词 extreme temperature stress response organizational members temperature fluctuation SUBTROPICAL
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A literature review and outlook of advertising avoidance:An integrated theoretical framework based on the SOMR model
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作者 Shengliang Zhang Jianhui Jin Xiaodong Li 《中国科学技术大学学报》 北大核心 2025年第1期2-16,1,I0001,共17页
Advertising avoidance is resistance to advertising intrusion.This issue has been the subject of much academic research in recent years.To guide scholars to better carry out relevant research and promote enterprises to... Advertising avoidance is resistance to advertising intrusion.This issue has been the subject of much academic research in recent years.To guide scholars to better carry out relevant research and promote enterprises to better implement advertising activities,this study intends to summarize the relevant research on advertising avoidance in recent years.The specific method is to use the core literature meta-analysis method to identify,filter,and screen relevant literature published in core journals from 1997 to 2020 with the keywords advertising avoidance and advertising resistance.We review the collected articles from the following perspectives:the definition and classification,external stimulating factors,internal perception factors,and moderating factors of advertising avoidance.On this basis,the SOMR model of advertising avoidance is constructed according to the SOR model.Finally,some prospects for future related research are presented. 展开更多
关键词 ADVERTISING advertising avoidance SOMR model perceived value perceived infringement
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Effect of tantalum doping on the microstructure and photoelectrical properties of transparent conductive zinc oxide films
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作者 Kai Yi Hongxu Jiang +3 位作者 Yanbo Cai Guangwei Wang Fei Liu Deliang Wang 《中国科学技术大学学报》 北大核心 2025年第4期49-57,48,I0002,共11页
ZnO thin films with varying Ta concentrations were fabricated through magnetron sputtering.The crystallinity and surface morphology of the ZnO films are significantly influenced by the incorporation of Ta,as evidenced... ZnO thin films with varying Ta concentrations were fabricated through magnetron sputtering.The crystallinity and surface morphology of the ZnO films are significantly influenced by the incorporation of Ta,as evidenced by the X-ray diffraction and scanning electron microscopy results.The lattice constants,as determined by X-ray diffraction,contradict the disparity in Ta and Zn ion radii,which is attributed to the impact of interstitial defects.This inconsistency introduces variations in carrier concentration in this experiment compared with prior studies.Subsequent exploration of the luminescent characteristics and emission mechanism of defect levels in Ta-doped ZnO films was conducted through photoluminescence.Furthermore,the factors influencing the bandgap are discussed. 展开更多
关键词 tantalum-doped zinc oxide RF magnetron sputtering MICROSTRUCTURE PHOTOLUMINESCENCE
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Leverage or crowd out:the National Independent Innovation Demonstration Zone policies and green innovation efficiency of enterprises
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作者 Haonan He Jiaxin Sun +2 位作者 Richard Samuel Freeman Dehong Li Shanyong Wang 《中国科学技术大学学报》 北大核心 2025年第1期32-44,31,I0001,共15页
The National Independent Innovation Demonstration Zone has been assigned the unique mission of demonstrating and leading national innovation and playing a key supportive role in enhancing green innovation.Based on the... The National Independent Innovation Demonstration Zone has been assigned the unique mission of demonstrating and leading national innovation and playing a key supportive role in enhancing green innovation.Based on the sample data of A-share listed companies in China from 2007 to 2021,we apply a multi-period difference-in-differences model to analyze whether the implementation of the National Independent Innovation Demonstration Zone policies plays a leverage effect or a crowd out effect on the green innovation efficiency of enterprises and systematically test the regulatory mechanism of government grants and media attention in the process of this influence.The empirical results show that the imple-mentation of the National Independent Innovation Demonstration Zone policies has a positive impact on the green innovation efficiency of enterprises and that the green innovation induced by this reform is not the leverage effect of additional R&D investment on the basis of the existing innovation activities of enterprises but rather the result of the reallocation of resources to crowd out existing non-green innovation.It is further found that government grants and media attention positively moderate the positive driving effect of National Independent Innovation Demonstration Zone policies on the green innovation efficiency of enterprises. 展开更多
关键词 National Independent Innovation Demonstration Zone policies green innovation efficiency leverage effect crowd out effect
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Influencing factor of the characterization and restoration of phase aberrations resulting from atmospheric turbulence based on Principal Component Analysis
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作者 WANG Jiang-pu-zhen WANG Zhi-qiang +2 位作者 ZHANG Jing-hui QIAO Chun-hong FAN Cheng-yu 《中国光学(中英文)》 北大核心 2025年第4期899-907,共9页
Restoration of phase aberrations is crucial for addressing atmospheric turbulence in light propagation.Traditional restoration algorithms based on Zernike polynomials(ZPs)often encounter challenges related to high com... Restoration of phase aberrations is crucial for addressing atmospheric turbulence in light propagation.Traditional restoration algorithms based on Zernike polynomials(ZPs)often encounter challenges related to high computational complexity and insufficient capture of high-frequency phase aberration components,so we proposed a Principal-Component-Analysis-based method for representing phase aberrations.This paper discusses the factors influencing the accuracy of restoration,mainly including the sample space size and the sampling interval of D/r_(0),on the basis of characterizing phase aberrations by Principal Components(PCs).The experimental results show that a larger D/r_(0)sampling interval can ensure the generalization ability and robustness of the principal components in the case of a limited amount of original data,which can help to achieve high-precision deployment of the model in practical applications quickly.In the environment with relatively strong turbulence in the test set of D/r_(0)=24,the use of 34 terms of PCs can improve the corrected Strehl ratio(SR)from 0.007 to 0.1585,while the Strehl ratio of the light spot after restoration using 34 terms of ZPs is only 0.0215,demonstrating almost no correction effect.The results indicate that PCs can serve as a better alternative in representing and restoring the characteristics of atmospheric turbulence induced phase aberrations.These findings pave the way to use PCs of phase aberrations with fewer terms than traditional ZPs to achieve data dimensionality reduction,and offer a reference to accelerate and stabilize the model and deep learning based adaptive optics correction. 展开更多
关键词 phase aberration atmospheric turbulence principal component analysis Zernike polynomials
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A Tentative Research on the National Recognition Mechanism on Chinese Scientists -- A Case Study of the Correlations Between the Academician System and the State Natural Science Award in China
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作者 XU Fei Zhao Ming 《学术界》 CSSCI 北大核心 2011年第11期266-273,共8页
关键词 英文摘要 内容介绍 编辑工作 期刊
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Effects of content and particle size of TiH2 powders on the energy output rules of RDX composite explosives 被引量:3
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作者 Hao Wang Yangfan Cheng +2 位作者 Shoujun Zhu Zihan Li Zhaowu Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期297-308,共12页
In order to improve the detonation characteristics of RDX,a RDX-based composite explosive with TiH_(2)powders was prepared.The effects of content and particle size of TiH_(2)powders on thermal safety,shock wave parame... In order to improve the detonation characteristics of RDX,a RDX-based composite explosive with TiH_(2)powders was prepared.The effects of content and particle size of TiH_(2)powders on thermal safety,shock wave parameters and thermal damage effects of RDX-based composite explosive were studied with the C80 microcalorimeter,air blast experiment system and colorimetric thermometry method.Experimental results showed that TiH_(2)powders could enhance the thermal stability of RDX-based composite explosive and increase its ultimate decomposition heat.The content and particle size of TiH_(2)powders also had significant effects on the thermal safety,detonation velocity,shock wave parameters,fireball temperature and duration of RDX-based composite explosives.Furthermore,the differences of TiH_(2)and Ti powders on the detonation energy output rules of RDX-based composite explosives were also compared,showing that TiH_(2)powders had better influences on improving the explosion power and thermal damage effect of RDX-based composite explosives than Ti powders,for the participation of free H_(2)released by TiH_(2)powders in the detonation process.TiH_(2)powders have important research values as a novel energetic additive in the field of military composite explosives. 展开更多
关键词 RDX Hydrogen storage alloy Air blast After-burn reaction Colorimetric thermometry
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Dietary oleic acid intake,olive oil consumption,and risk of cardiovascular and all-cause mortality 被引量:2
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作者 Huihui Lu Buyun Liu +3 位作者 Wenjun Fu Kaiwen Ji Shuang Rong Wei Bao 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第9期45-53,69,70,共11页
Objective:Oleic acid,a subtype of monounsaturated fatty acid(MUFA),is present in abundance in certain edible oils,particularly olive oils.Epidemiological evidence concerning dietary oleic acid intake and the long-term... Objective:Oleic acid,a subtype of monounsaturated fatty acid(MUFA),is present in abundance in certain edible oils,particularly olive oils.Epidemiological evidence concerning dietary oleic acid intake and the long-term risk of mortality is lacking.This study aimed to evaluate the associations of the dietary intake of oleic acid and other specific subtypes of MUFAs,olive oil,and other vegetable oils with cardiovascular disease(CVD)and all-cause mortality.Methods:This prospective cohort study included adults aged 40 years or older who participated in the included U.S.adults National Health and Nutrition Examination Survey(NHANES).Dietary MUFA intake was assessed via 24-h dietary recall interviews in NHANES 1999–2018,and the consumption of olive oil and other vegetable oils was assessed via a food frequency questionnaire in NHANES 2003–2006.Deaths and underlying causes of death were ascertained by linkage to the National Death Index through December 31,2019.Weighted Cox proportional hazards regression models were used to estimate the hazard ratio(HR)and 95%CIs.Results:Dietary intake of total MUFAs and oleic acid was associated with a lower risk of CVD mortality,with HRs(95%CI)of 0.62(0.39–0.99)and 0.61(0.39–0.97),respectively.Total MUFA and oleic acid intake were inversely associated with all-cause mortality;the multivariable-adjusted HRs were 0.77(95%CI:0.60–0.99)and 0.78(95%CI:0.62–0.99),respectively.There was no significant association between palmitoleic acid intake and all-cause mortality.The habitual consumption of olive oil,but not the consumption of other vegetable oils,was inversely associated with the risk of cardiovascular mortality.In the joint association analysis,the HRs(95%CI)of cardiovascular mortality were 0.36(0.19–0.69)for people who exclusively consumed olive oil,0.59(0.27–1.32)for people who consumed both olive oil and other vegetable oils,and 0.73(0.46–1.14)for people who exclusively consumed other vegetable oils compared with people who never consumed vegetable oils.Conclusions:In a U.S.nationally representative prospective cohort,higher dietary oleic acid intake and olive oil consumption were associated with a lower risk of cardiovascular mortality. 展开更多
关键词 oleic acid monounsaturated fatty acid olive oil cardiovascular mortality all-cause mortality
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The chitosan encapsulation strategy inhibits the dissolution of MoS_(2)/ZnO nanoparticles in water disinfection
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作者 Yutao Xie Yunpeng Yu Feng Gao 《中国科学技术大学学报》 北大核心 2025年第3期28-38,27,I0002,共13页
The combination of solar disinfection and photocatalysis technology presents a viable solution for eliminating harmful pathogenic microorganisms from water.However,some photocatalysts(e.g.,zinc oxide-based composites)... The combination of solar disinfection and photocatalysis technology presents a viable solution for eliminating harmful pathogenic microorganisms from water.However,some photocatalysts(e.g.,zinc oxide-based composites)are susceptible to pH-dependent dissolution in water,which can result in the loss of photocatalysts and additional environ-mental pollution.To obtain zinc oxide-based composites with low dissolution and high antibacterial efficiency for pho-tocatalytic water disinfection,we prepared MoS_(2)/ZnO@CS composites via a precipitation method to encapsulate chitosan(CS)around MoS_(2)/ZnO.The amino groups in the CS molecules act as storerooms for hydrogen ions,which inhibits the dissolution of zinc oxide.In addition,the MoS_(2)/ZnO@CS composites exhibit high production of reactive oxygen species(ROS)and broad-spectrum antibacterial activity under simulated solar irradiation(0.1 W·cm^(-2)).This makes it an excellent antibacterial agent for solar disinfection in water treatment. 展开更多
关键词 ZnO MoS_(2) CHITOSAN ANTIBACTERIAL water disinfection
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Unbiased test of the hyperon CP violation in terms of detector resolution at STCF
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作者 Ming Xu Liang Liu +2 位作者 Yupeng Pei Xiaorong Zhou Yingchun Zhu 《中国科学技术大学学报》 北大核心 2025年第4期41-47,40,I0002,共9页
The study of the charge conjugation and parity(CP)violation of hyperon is the precision frontier for probing possible new CP violation sources beyond the standard model(SM).With the large number of quantum entangled h... The study of the charge conjugation and parity(CP)violation of hyperon is the precision frontier for probing possible new CP violation sources beyond the standard model(SM).With the large number of quantum entangled hyperonantihyperon pairs to be produced at Super Tau-Charm Facility(STCF),the CP asymmetry of hyperon is expected to be tested with a statistical sensitivity of 10−4 or even better.To cope with the statistical precision,the systematic effects from various aspects are critical and need to be studied in detail.In this paper,the sensitivity effects on the CP violation parameters associated with the detector resolution,including those of the position and momentum,are studied and discussed in detail.The results provide valuable guidance for the design of STCF detector. 展开更多
关键词 BESIII experiment STCF hyperon CP violation detector resolution unbiased test
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Effects of the oxygen transport properties of electrolytes on the reaction mechanisms in lithium-oxygen batteries
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作者 Aijing Yan Zhuojun Zhang +1 位作者 Xu Xiao Peng Tan 《中国科学技术大学学报》 北大核心 2025年第2期35-42,34,I0001,I0002,共11页
Lithium-oxygen batteries attract considerable attention due to exceptionally high theoretical energy density,while the development remains in its early stage.As is widely suggested,the solution mechanism induces great... Lithium-oxygen batteries attract considerable attention due to exceptionally high theoretical energy density,while the development remains in its early stage.As is widely suggested,the solution mechanism induces greater discharge capacity,while the surface mechanism induces greater cycle stability.Therefore,battery performance can be improved by adjusting the reaction mechanism.Previous studies predominantly focus on extremely thin or flat electrodes.In contrast,this work utilizes thick electrodes,emphasizing the importance of mass transport.Given that the electrolyte solvent is the main site of mass transport,the effects of two typical solvents on mass transport and battery performance are investigated:dimethyl sulfoxide with low viscosity and a high O_(2) diffusion rate and tetraethylene glycol dimethyl ether with high O_(2) solubility and high Li+transport capability.The results reveal a novel pathway for reaction mechanism induction where the mechanism varies with the spatial position of the electrode.As the spatial distribution of the electrode progresses,a layered appearance of solution mechanism products,transition state products,and surface mechanism products emerges,which is attributed to the increase in the mass transfer resistance.This work presents a distinct perspective on the way solvents influence reaction pathways and offers a new approach to regulating reaction pathways. 展开更多
关键词 Li-O_(2)battery nonaqueous electrolyte oxygen transport property solution mechanism surface mechanism
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Evolution of the volume expansion of SiO/C composite electrodes in lithium-ion batteries during aging cycles
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作者 Haosong Yang Kai Sun +2 位作者 Xueyan Li Peng Tan Lili Gong 《中国科学技术大学学报》 北大核心 2025年第2期27-33,26,I0001,共9页
As a negative electrode material for lithium-ion batteries,silicon monoxide(SiO)suffers from dramatic volume changes during cycling,causing excessive stress within the electrode and resulting in electrode deformation ... As a negative electrode material for lithium-ion batteries,silicon monoxide(SiO)suffers from dramatic volume changes during cycling,causing excessive stress within the electrode and resulting in electrode deformation and fragmentation.This ultimately leads to a decrease in cell capacity.The trends of volume expansion and capacity change of the SiO/graphite(SiO/C)composite electrode during cycling were investigated via in situ expansion monitoring.First,a series of expansion test schemes were designed,and the linear relationship between negative electrode expansion and cell capacity degradation was quantitatively analyzed.Then,the effects of different initial pressures on the long-term cycling performance of the cell were evaluated.Finally,the mechanism of their effects was analyzed by scanning electron microscope.The results show that after 50 cycles,the cell capacity decreases from 2.556 mAh to 1.689 mAh,with a capacity retention ratio(CRR)of only 66.08%.A linear relationship between the capacity retention ratio and thickness expansion was found.Electrochemical measurements and scanning electron microscope images demonstrate that intense stress inhibits the lithiation of the negative electrode and that the electrode is more susceptible to irreversible damage during cycling.Overall,these results reveal the relationship between the cycling performance of SiO and the internal pressure of the electrode from a macroscopic point of view,which provides some reference for the application of SiO/C composite electrodes in lithium-ion batteries. 展开更多
关键词 lithium-ion batteries in situ expansion measurement initial stress cycle life SiO/C composite electrode
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Effects of the wavy leading-edge wavelength on the reduction in the noise of the rod-airfoil configuration
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作者 Fuyang Yu Zhenhua Wan +1 位作者 Yasen Hu Dejun Sun 《中国科学技术大学学报》 北大核心 2025年第2期19-25,18,I0001,共9页
Rod-airfoil interaction noise becomes a major issue in some aeronautical applications.The design of four wavy leading edges(WLEs)with varying wavelengths,bioinspired by the tubercles on humpback whales’flippers,aims ... Rod-airfoil interaction noise becomes a major issue in some aeronautical applications.The design of four wavy leading edges(WLEs)with varying wavelengths,bioinspired by the tubercles on humpback whales’flippers,aims to mitigate far-field noise.Among these cases,a reduction in the wavelength is found to be advantageous for noise suppression,with the smallest wavelength case achieving a maximum noise reduction of 1.9 dB.Furthermore,the noise radiation induced by WLEs is suppressed mainly at medium frequencies.The theory of multiprocess aeroacoustics is applied to reveal their underlying mechanisms.The dominant factor is the source cutoff effect,which significantly decreases the source strength on hills.Additionally,spanwise decoherence with phase interference serves as another crucial mechanism,particularly for reducing mid-frequency noise. 展开更多
关键词 rod-airfoil wavy leading edge WAVELENGTH multiprocess acoustic theory
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The use of a ternary metal sulfide loading on carbon fibers as the sulfur host for high performance low-temperature lithium sulfur batteries
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作者 HE Xin ZUO Huai-yang +4 位作者 XIAO Ru QU Zhuo-yan SUN Zhen-hua WANG Bao Li Feng 《新型炭材料(中英文)》 北大核心 2025年第1期167-177,共11页
The use of lithium-sulfur(Li-S)batteries is limited by sulfur redox reactions involving multi-phase transformations,especially at low-temperatures.To address this issue,we report a material(FCNS@NCFs)consisting of nit... The use of lithium-sulfur(Li-S)batteries is limited by sulfur redox reactions involving multi-phase transformations,especially at low-temperatures.To address this issue,we report a material(FCNS@NCFs)consisting of nitrogen-doped carbon fibers loaded with a ternary metal sulf-ide((Fe,Co,Ni)_(9)S_(8))for use as the sulfur host in Li-S batteries.This materi-al was prepared using transfer blot filter paper as the carbon precursor,thiourea as the source of nitrogen and sulfur,and FeCl_(3)·6H_(2)O,CoCl_(2)·6H_(2)O and NiCl_(2)·6H_(2)O as the metal ion sources.It was synthesized by an impreg-nation method followed by calcination.The nitrogen doping significantly in-creased the conductivity of the host,and the metal sulfides have excellent catalytic activities.Theoretical calculations,and adsorption and deposition experiments show that active sites on the surface of FCNS@NCFs selectively adsorb polysulfides,facilitate rapid adsorption and conversion,prevent cathode passivation and inhib-it the polysulfide shuttling.The FCNS@NCFs used as the sulfur host has excellent electrochemical properties.Its initial dis-charge capacity is 1639.0 mAh g^(−1) at 0.2 C and room temperature,and it remains a capacity of 1255.1 mAh g^(−1) after 100 cycles.At−20~C,it has an initial discharge capacity of 1578.5 mAh g^(−1) at 0.2 C,with a capacity of 867.5 mAh g^(−1) after 100 cycles.Its excellent performance at both ambient and low temperatures suggests a new way to produce high-performance low-temper-ature Li-S batteries. 展开更多
关键词 Lithium sulfur batteries Low temperature Transition metal sulfides Sulfur conversion kinetics
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Three-dimensional localization of the individual shallow NV center in diamond using a gold tip
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作者 Jiarui Qi Xinghang Chen +1 位作者 Mengqi Wang Ya Wang 《中国科学技术大学学报》 北大核心 2025年第4期35-39,34,I0002,共7页
This work presents a method for the three-dimensional localization of individual shallow NV center in diamond,leveraging the near-field quenching effect of a gold tip.Our experimental setup involves the use of an atom... This work presents a method for the three-dimensional localization of individual shallow NV center in diamond,leveraging the near-field quenching effect of a gold tip.Our experimental setup involves the use of an atomic force microscope to precisely move the gold tip close to the NV center,while simultaneously employing a home-made confocal microscope to monitor the fluorescence of the NV center.This approach allows for lateral super-resolution,achieving a full width at half maximum(FWHM)of 38.0 nm and a location uncertainty of 0.7 nm.Additionally,we show the potential of this method for determining the depth of the NV centers.We also attempt to determine the depth of the NV centers in combination with finite-difference time-domain(FDTD)simulations.Compared to other depth determination methods,this approach allows for simultaneous lateral and longitudinal localization of individual NV centers,and holds promise for facilitating manipulation of the local environment surrounding the NV center. 展开更多
关键词 NV center super-resolution localization atom force microscopy
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Dynamic behavior of a battery pack based on single reference impact testing of a secondary cell
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作者 Zhen Xiao Wen-rong Fan Wei-song Hu 《中国科学技术大学学报》 北大核心 2025年第2期44-50,43,I0002,共9页
The mechanical properties of secondary cells are crucial to the safety and reliability of battery packs,which can fail due to extrusion and vibration in a vehicle crash.To analyze the structural response of the second... The mechanical properties of secondary cells are crucial to the safety and reliability of battery packs,which can fail due to extrusion and vibration in a vehicle crash.To analyze the structural response of the secondary cell and its other dynamic behaviors,the experiment and some numerical simulations were carried out based on single reference impact testing.Then,an equivalent constitutive relationship of the secondary cell was proposed to reveal the dynamic properties and used to guide the safety estimation of the battery pack.As the input parameter to the finite element model,the equivalent constitutive relationship,including but not limited to the elastic modulus and stain-stress curve,determines the simulation precision of the battery packs.Compared to the experimental results of the natural frequency of the battery pack,the simulation error is below 2%when the elastic modulus of the secondary cell in the battery pack has been verified. 展开更多
关键词 equivalent constitutive relationship secondary cell dynamic property
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Study on the effects of combustion characteristics of pyrotechnic charges on pyrotechnic shocks
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作者 Jingcheng Wang Shihui Xiong +2 位作者 Huina Mu Xiaogang Li Yuquan Wen 《Defence Technology(防务技术)》 2025年第4期79-98,共20页
This study calculates the combustion characteristics of various gas-generating and micro gas pyrotechnic charges,including aluminium/potassium perchlorate,boron/potassium nitrate,carbon black/potassium nitrate,and sil... This study calculates the combustion characteristics of various gas-generating and micro gas pyrotechnic charges,including aluminium/potassium perchlorate,boron/potassium nitrate,carbon black/potassium nitrate,and silicon-based delay compositions,using thermodynamic software.A multiphase flowthermal-solid coupling model was established,and the combustion process of the pyrotechnic charges within a closed bomb was simulated.The pyrotechnic shock generated by combustion was predicted.The combustion pressures and pyrotechnic shocks were measured.The simulation results demonstrated good agreement with experimental results.Additionally,the mechanism of shock generation by the combustion of pyrotechnic charges in the closed bomb was analyzed.The effects of the combustion characteristics of the pyrotechnic charges on the resulting pyrotechnic shocks were systematically investigated.Notably,the shock response spectrum of the gas-generating pyrotechnic charges is greater than that of the micro gas compositions at most frequencies,particularly in the mid-field pyrotechnic shocks(3-10 kHz).Furthermore,the pyrotechnic shocks increase approximately linearly with the impulse of the gas-generating pyrotechnic charges. 展开更多
关键词 Pyrotechnic charges Pyroshock Closed bomb tests Combustion characteristics Multiphase flow-thermal-solid coupling
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Effect of substrate temperature and oxygen plasma treatment on the properties of magnetron-sputtered CdS for solar cell applications
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作者 Runxuan Zang Haolin Wang +9 位作者 Xiaoqi Peng Ke Li Yuehao Gu Yizhe Dong Zhihao Yan Zhiyuan Cai Huihui Gao Shuwei Sheng Rongfeng Tang Tao Chen 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第6期22-33,I0010,共13页
Cadmium sulfide(CdS)is an n-type semiconductor with excellent electrical conductivity that is widely used as an electron transport material(ETM)in solar cells.At present,numerous methods for preparing CdS thin films h... Cadmium sulfide(CdS)is an n-type semiconductor with excellent electrical conductivity that is widely used as an electron transport material(ETM)in solar cells.At present,numerous methods for preparing CdS thin films have emerged,among which magnetron sputtering(MS)is one of the most commonly used vacuum techniques.For this type of technique,the substrate temperature is one of the key deposition parameters that affects the interfacial properties between the target film and substrate,determining the specific growth habits of the films.Herein,the effect of substrate temperature on the microstructure and electrical properties of magnetron-sputtered CdS(MS-CdS)films was studied and applied for the first time in hydrothermally deposited antimony selenosulfide(Sb_(2)(S,Se)_(3))solar cells.Adjusting the substrate temperature not only results in the design of the flat and dense film with enhanced crystallinity but also leads to the formation of an energy level arrangement with a Sb_(2)(S,Se)_(3)layer that is more favorable for electron transfer.In addition,we developed an oxygen plasma treatment for CdS,reducing the parasitic absorption of the device and resulting in an increase in the short-circuit current density of the solar cell.This study demonstrates the feasibility of MS-CdS in the fabrication of hydrothermal Sb_(2)(S,Se)_(3)solar cells and provides interface optimization strategies to improve device performance. 展开更多
关键词 magnetron sputtering CDS substrate heating plasma treatment Sb_(2)(S Se)_(3) thin film solar cell
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Characterization and synthetic biology elements of nonmodel bacteria,Acetobacteraceae
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作者 Yanmei Gao 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第9期55-67,70,共14页
Acetobacteraceae has garnered significant attention because of its unique properties and the broad applications of the bacterial cellulose it produces.However,unlike model strains,Acetobacteraceae have few synthetic b... Acetobacteraceae has garnered significant attention because of its unique properties and the broad applications of the bacterial cellulose it produces.However,unlike model strains,Acetobacteraceae have few synthetic biology applications because they are difficult to manipulate genetically and have insufficient genetic regulatory elements,among other factors.To address this limitation,this study characterized the fundamental properties and synthetic biology elements of three commonly used bacterial cellulose-producing strains.First,the basic characteristics of the three strains,including their cellulose film production ability,division time,antibiotic susceptibility,and plasmid features,were analyzed.Two inducible promoters(pTrc and pLux101)were subsequently characterized within the three strains.The inducibility of the pTrc promoter was relatively low across the three strains(induction ratio:1.98–6.39),whereas the pLux101 promoter demonstrated a significantly greater level of inducibility within the three strains(induction ratio:87.28–216.71).Finally,through gene knockout experiments,this study identified four genes essential for bacterial cellulose film production in the genome of the Gluconacetobacter hansenii ATCC 5358 strain.This study not only enriches the library of synthetic biology elements in nonmodel strains,but also lays the foundation for the synthetic biology applications of Acetobacteraceae. 展开更多
关键词 synthetic biology ACETOBACTERACEAE bacterial cellulose inducible promoter nonmodel bacteria
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