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Combing the Entropy Weight Method with Fuzzy Mathematics for Assessing the Quality and Post-Ripening Mechanism of High-Temperature Daqu during Storage 被引量:1
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作者 YANG Junlin YANG Shaojuan +8 位作者 WU Cheng YIN Yanshun YOU Xiaolong ZHAO Wenyu ZHU Anran WANG Jia HU Feng HU Jianfeng WANG Diqiang 《食品科学》 北大核心 2025年第9期48-62,共15页
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar... This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu. 展开更多
关键词 microbial community high-temperature Daqu comprehensive quality evaluation entropy weight method maturation process
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Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2 被引量:1
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作者 Qing He Zhen Wang +5 位作者 Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu Gong Chen 《Neural Regeneration Research》 SCIE CAS 2025年第6期1801-1815,共15页
Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders.... Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain. 展开更多
关键词 AQUAPORIN-4 Ascl1 ASTROCYTE cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 REPROGRAMMING
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Novel entropy-stabilized spinel materials and their potential application in high-temperature industry:[(Mg_(x)Zn_((1-x)/2)Cu_((1-x)/2))(Al_(0.9)Fe_(0.1))_(2)O_(4)](x=0.5,0.6,0.7,and 0.8) 被引量:1
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作者 Bo-Kang Li Lv-Ping Fu +2 位作者 Hua-Zhi Gu Ao Huang Shuang Yang 《Rare Metals》 2025年第8期5844-5858,共15页
High-temperature industries,as the primary consumers of energy,are greatly concerned with energy savings.Designing refractory linings with low thermal conductivity to reduce heat dissipation through high-temperature f... High-temperature industries,as the primary consumers of energy,are greatly concerned with energy savings.Designing refractory linings with low thermal conductivity to reduce heat dissipation through high-temperature furnace linings is a critical concern.In this study,a series of novel entropy-stabilized spinel materials are reported,and their potential applications in high-temperature industries are investigated.XRD and TEM results indicate that all materials possess a cubic spinel crystal structure with the■space group.Furthermore,these materials exhibit good phase stability at high temperatures.All entropy-stabilized spinel aggregates demonstrated high refractoriness(>1800℃)and a high load softening temperature(>1700℃).The impact of configurational entropy on the properties of entropy-stabilized spinel materials was also studied.As configurational entropy increased,the thermal conductivity of the entropy-stabilized spinel decreased,while slag corrosion resistance deteriorated.For the entropy-stabilized spinel with a configurational entropy value of 1.126R,it showed good high-temperature stability,reliable resistance to slag attack,and a low thermal conductivity of 2.776 W·m^(-1)·K^(-1)at 1000℃. 展开更多
关键词 Entropy-stabilized spinel Thermal conductivity high-temperature performance Configurational entropy
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Conversion treatment for advanced intrahepatic cholangiocarcinoma:Opportunities and challenges 被引量:2
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作者 Jun-Jie Liu Mi Zhou +2 位作者 Tong Yuan Zhi-Yong Huang Zun-Yi Zhang 《World Journal of Gastroenterology》 2025年第15期24-41,共18页
The prevalence of intrahepatic cholangiocarcinoma(ICC)is increasing globally.Despite advancements in comprehending this intricate malignancy and formulating novel therapeutic approaches over the past few decades,the p... The prevalence of intrahepatic cholangiocarcinoma(ICC)is increasing globally.Despite advancements in comprehending this intricate malignancy and formulating novel therapeutic approaches over the past few decades,the prognosis for ICC remains poor.Owing to the high degree of malignancy and insidious onset of ICC,numerous cases are detected at intermediate or advanced stages of the disease,hence eliminating the chance for surgical intervention.Moreover,because of the highly invasive characteristics of ICC,recurrence and metastasis postresection are prevalent,leading to a 5-year survival rate of only 20%-35%following surgery.In the past decade,different methods of treatment have been investigated,including transarterial chemoembolization,transarterial radioembolization,radiotherapy,systemic therapy,and combination therapies.For certain patients with advanced ICC,conversion treatment may be utilized to facilitate surgical resection and manage disease progression.This review summarizes the definition of downstaging conversion treatment and presents the clinical experience and evidence concerning conversion treatment for advanced ICC. 展开更多
关键词 Intrahepatic cholangiocarcinoma conversion treatment DOWNSTAGING Combination therapy Chemotherapy IMMUNOTHERAPY Locoregional therapies
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Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni_(2)P for lithium-sulfur batteries 被引量:2
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作者 Lin Peng Yu Bai +3 位作者 Hang Li Meixiu Qu Zhenhua Wang Kening Sun 《Journal of Energy Chemistry》 2025年第1期760-769,共10页
Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish ... Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox dynamics.Herein,we supply a strategy to optimize the electron structure of Ni_(2)P by concurrently introducing B-doped atoms and P vacancies in Ni_(2)P (Vp-B-Ni_(2)P),thereby enhancing the bidirectional sulfur conversion.The study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni_(2)P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides (LiPSs) as well as expediting the bidirectional conversion kinetics of sulfur species.Meanwhile,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni_(2)P selectively promotes Li2S dissolution and nucleation processes.Thus,the Li-S batteries with Vp-B-Ni_(2)P-separators present outstanding rate ability of 777 m A h g^(-1)at 5 C and high areal capacity of 8.03 mA h cm^(-2)under E/S of 5μL mg^(-1)and sulfur loading of 7.20 mg cm^(-2).This work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion. 展开更多
关键词 B-doped atoms P vacancies Nickel phosphide Bidirectional sulfur conversion Lithium-sulfur batteries
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Solvent engineering in perovskite nanocrystal colloid inks for super-fine electrohydrodynamic inkjet printing of color conversion microstructures in micro-LED displays 被引量:2
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作者 Shuli Wang Xuemin Kong +7 位作者 Siting Cai Yunshu Luo Yuxuan Gu Xiaotong Fan Guolong Chen Xiao Yang Zhong Chen Yue Lin 《Chinese Chemical Letters》 2025年第8期554-559,共6页
Super-fine electrohydrodynamic inkjet(SIJ)printing of perovskite nanocrystal(PNC)colloid ink exhibits significant potential in the fabrication of high-resolution color conversion microstructures arrays for fullcolor m... Super-fine electrohydrodynamic inkjet(SIJ)printing of perovskite nanocrystal(PNC)colloid ink exhibits significant potential in the fabrication of high-resolution color conversion microstructures arrays for fullcolor micro-LED displays.However,the impact of solvent on both the printing process and the morphology of SIJ-printed PNC color conversion microstructures remains underexplored.In this study,we prepared samples of CsPbBr3PNC colloid inks in various solvents and investigated the solvent's impact on SIJ printed PNC microstructures.Our findings reveal that the boiling point of the solvent is crucial to the SIJ printing process of PNC colloid inks.Only does the boiling point of the solvent fall in the optimal range,the regular positioned,micron-scaled,conical PNC microstructures can be successfully printed.Below this optimal range,the ink is unable to be ejected from the nozzle;while above this range,irregular positioned microstructures with nanoscale height and coffee-ring-like morphology are produced.Based on these observations,high-resolution color conversion PNC microstructures were effectively prepared using SIJ printing of PNC colloid ink dispersed in dimethylbenzene solvent. 展开更多
关键词 SOLVENT Perovskite nanocrystal Electrohydrodynamic inkjet printing Color conversion microstructures arrays Micro-LED display
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Impact of Burial Dissolution on the Development of Ultradeep Fault-controlled Carbonate Reservoirs:Insights from High-temperature and High-pressure Dissolution Kinetic Simulation 被引量:1
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作者 TAN Xiaolin ZENG Lianbo +6 位作者 SHE Min LI Hao MAO Zhe SONG Yichen YAO Yingtao WANG Junpeng LU Yuzhen 《Acta Geologica Sinica(English Edition)》 2025年第1期228-242,共15页
Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temper... Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temperature and highpressure dissolution kinetic simulations were conducted.The results demonstrate that the intensity of burial dissolution is controlled by temperature and pressure,while tectonic-fluid activity influences the development pattern of burial dissolution,ultimately determining the direction of its differential modification.Extensive burial dissolution is likely to occur primarily at relatively shallow depths,significantly influencing reservoir formation,preservation,modification,and adjustment.The development of faults facilitates the maintenance of the intensity of burial dissolution.The maximum intensity of burial dissolution occurs at the tips and overlap zones of faults and intersections of multiple faults.The larger the scale of the faults,the more conducive it is to the development of burial dissolution.Burial dissolution fosters the formation of fault networks characterized by enhanced reservoir capacity and permeability.Burial dissolution controlled by episodic tectonic-fluid activity is a plausible explanation for forming the Tarim Basin's ultra-deep fault-controlled“stringbead-like”reservoirs. 展开更多
关键词 burial dissolution tectonic-fluid ultra-deep carbonate reservoirs high-temperature and high-pressure dissolution kinetic simulation
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In Situ Partial-Cyclized Polymerized Acrylonitrile-Coated NCM811 Cathode for High-Temperature≥100℃ Stable Solid-State Lithium Metal Batteries 被引量:1
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作者 Jiayi Zheng Haolong Jiang +13 位作者 Xieyu Xu Jie Zhao Xia Ma Weiwei Sun Shuangke Liu Wei Xie Yufang Chen ShiZhao Xiong Hui Wang Kai Xie Yu Han Maoyi Yi Chunman Zheng Qingpeng Guo 《Nano-Micro Letters》 2025年第8期399-415,共17页
High-nickel ternary cathodes hold a great application prospect in solid-state lithium metal batteries to achieve high-energy density,but they still suffer from structural instability and detrimental side reactions wit... High-nickel ternary cathodes hold a great application prospect in solid-state lithium metal batteries to achieve high-energy density,but they still suffer from structural instability and detrimental side reactions with the solid-state electrolytes.To circumvent these issues,a continuous uniform layer polyacrylonitrile(PAN)was introduced on the surface of LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2) via in situ polymerization of acrylonitrile(AN).Furthermore,the partial-cyclized treatment of PAN(cPAN)coating layer presents high ionic and electron conductivity,which can accelerate interfacial Li+and electron diffusion simultaneously.And the thermodynamically stabilized cPAN coating layer cannot only effectively inhibit detrimental side reactions between cathode and solid-state electrolytes but also provide a homogeneous stress to simultaneously address the problems of bulk structural degradation,which contributes to the exceptional mechanical and electrochemical stabilities of the modified electrode.Besides,the coordination bond interaction between the cPAN and NCM811 can suppress the migration of Ni to elevate the stability of the crystal structure.Benefited from these,the In-cPAN-260@NCM811 shows excellent cycling performance with a retention of 86.8%after 300 cycles and superior rate capability.And endow the solid-state battery with thermal safety stability even at hightemperature extreme environment.This facile and scalable surface engineering represents significant progress in developing high-performance solid-state lithium metal batteries. 展开更多
关键词 Solid-state lithium metal battery Ni-rich cathode Interface engineering In situ partial-cyclized PAN high-temperature resistance
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Hierarchical porous SiC_(nws)/SiC composites with one-dimensional oriented assemblies for high-temperature broadband wave absorption 被引量:1
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作者 Huiying Ouyang Xiao You +6 位作者 Yuanhang Yang Meihan Ren Qiuqi Zhang Ruixiang Deng Xiangyu Zhang Jinshan Yang Shaoming Dong 《Journal of Materials Science & Technology》 2025年第11期1-10,共10页
The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(S... The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(SiC_(nws))/SiC composites are fabricated with in-situ SiC interface on one-dimensional oriented SiC_(nws)skeleton,which collaborative configuration by 3D printing and freeze casting assembly.The con-structed porous structure optimizes the impedance matching degree and scattering intensity,the maximum effective absorption bandwidth(EAB_(max))of 5.9 GHz and the minimum reflection loss(RL_(min))of−41.4 dB can be realized.Considering the inherent oxidation resistance of SiC,the composites present well-maintained absorption performance at 600℃.Even at 1100℃,the EAB_(max)of 4.9 GHz and RLmin of−30.4 dB also demonstrate the high-temperature absorption stability of the composites,indicating exceptional wave absorption properties and thermal stability.The slight attenuation can be attributed to the decrease in impedance matching capability accompanying the elevated dielectric constant.This work clarifies the impact of structure and component synergy on wave absorption behavior,and offers a novel approach to producing high-performance and high-temperature resistance ceramic-based electromagnetic wave absorption materials suitable for extreme environments. 展开更多
关键词 Electromagnetic wave absorption Porous structure INTERFACE SiC_(nws)/SiC composites high-temperature resistance
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Preparation and High-Temperature Oxidation Performance of TiC-NiCr Cermet
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作者 Zhang Lei Huang Bensheng +4 位作者 Xie Chuandi Chen Gen Du Jiao Sun Haishen Zuo Hanyang 《稀有金属材料与工程》 北大核心 2025年第5期1194-1206,共13页
Powder metallurgy was used to fabricate TiC-NiCr cermets and the oxidation behavior at 900℃ was investigated.Results reveal that TiC-NiCr cermets have uniform structures with excellent mechanical properties,whose har... Powder metallurgy was used to fabricate TiC-NiCr cermets and the oxidation behavior at 900℃ was investigated.Results reveal that TiC-NiCr cermets have uniform structures with excellent mechanical properties,whose hardness is 65 HRC and flexural strength is 1450 MPa.The high-temperature oxidation mechanism of TiC-based cermets was investigated through an X-ray diffractometer and scanning electron microscope.The added elements Ni and Cr along with their solid solutions not only bond with the hard phase TiC to ensure the physical performance of the cermet,but also impede the internal diffusion during oxidation by forming a dense composite oxide layer,thereby enhancing the oxidation resistance.The TiC-NiCr cermet exhibits a dense protective oxide layer at 900℃ and can endure continuous oxidation for approximately 1000 h.A methodology for fabricating TiC-NiCr metal matrix composites is proposed,and their oxidation resistance is evaluated,providing a theoretical and practical basis for simultaneously enhancing the mechanical properties and oxidation resistance and reducing production costs. 展开更多
关键词 TiC-NiCr microstructure high-temperature oxidation thermodynamics and kinetics
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Diamond related materials for energy storage and conversion applications
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作者 YU Si-yu WANG Xi-yan YANG Nian-jun 《新型炭材料(中英文)》 北大核心 2025年第4期973-992,共20页
Diamond combines many unique properties,including high stability,strong optical dispersion,excellent mechanical strength,and outstanding thermal conductivity.Its structure,surface groups,and electrical conductivity ar... Diamond combines many unique properties,including high stability,strong optical dispersion,excellent mechanical strength,and outstanding thermal conductivity.Its structure,surface groups,and electrical conductivity are also tunable,increasing its functional versatility.These make diamond and its related materials,such as its composites,highly promising for various applications in energy fields.This review summarizes recent advances and key achievements in energy storage and conversion,covering electrochemical energy storage(e.g.,batteries and supercapacitors),electrocatalytic energy conversion(e.g.,CO_(2)and nitrogen reduction reactions),and solar energy conversion(e.g.,photo-(electro)chemical CO_(2)and nitrogen reduction reactions,and solar cells).Current challenges and prospects related to the synthesis of diamond materials and the technologies for their energy applications are outlined and discussed. 展开更多
关键词 Diamond related materials Electrochemical energy storage Electrocatalytic energy conversion Solar energy conversion Future energy application directions
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A thermally-cyclized electrospun GO/PAN nanofiber piezoelectric sensor for high-temperature applications
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作者 LI Wei-dong LI Yin-hui +5 位作者 YIN Rong-yan FAN Kai GAO Fei LIANG Jian-guo LI Peng-wei BIAN Gui-bin 《新型炭材料(中英文)》 北大核心 2025年第5期1154-1168,I0051-I0057,共22页
High-temperature piezoelectric sen-sors are very important in severe environments such as fire safety,aerospace and oil drills,however,most current sensors are not heat res-istant(<300℃)and are fragile,which limit... High-temperature piezoelectric sen-sors are very important in severe environments such as fire safety,aerospace and oil drills,however,most current sensors are not heat res-istant(<300℃)and are fragile,which limits their use,especially in high-temperature environ-ments.A high-temperature resistant flexible piezoelectric film based on graphene oxide(GO)/polyacrylonitrile(PAN)composites was prepared by electrospinning and thermal treat-ment.It was packed into a micro-device,which could work continuously at 500℃.The intro-duction of GO significantly increased the mechanical properties of the PAN nanofibers because the oxygen-containing func-tional groups(electronegative groups)on the surface of the GO initiated a nucleophilic attack on the PAN molecule during heat treatment,enabling the GO to initiate the cyclization of the PAN at lower heat-treatment temperatures.In addition,the abund-ant oxygen-containing functional groups on GO acted as pro-oxidants to hasten the oxidation of PAN during heat treatment.The effects of GO content and heat treatment temperature on the properties of the nanofiber films were investigated.A GO/PAN nanofiber piezoelectric sensor heat-treated at 300℃had a 9.10 V and 2.25μA peak output,which are respectively 101.3%and 78.6%higher than those of the untreated films.Cyclic testing over 5000 cycles at 350℃confirmed the stable out-put performance of the GO/PAN nanofiber piezoelectric sensor.Furthermore,a sensor heat-treated at 400℃had a sensitivity of 1.7 V/N,which is 83.5%higher than that of an untreated one.The results show that the prepared GO/PAN nanofiber piezo-electric sensor combines high temperature resistance,high flexibility,stability and high sensitivity,and may have broad applic-ations in high temperature environments such as the aerospace and petroleum industries. 展开更多
关键词 GO/PAN nanofiber PIEZOELECTRIC high-temperature Thermal-cyclization Fully flexible
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Effect of Co Content on Microstructure and Mechanical Properties of High-Entropy High-Temperature Shape Memory Alloy
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作者 Zhao Yanchun Jin Bo +4 位作者 Feng Yuanfei Ma Huwen Yu Zhiqi Feng Li Liaw Peter K 《稀有金属材料与工程》 北大核心 2025年第1期10-16,共7页
(TiZrHf)_(50)Ni_(30)Cu_(20-x)Co_(x)(x=2,4,6,at%)high-entropy high-temperature shape memory alloys were fabricated by watercooled copper crucible in a magnetic levitation vacuum melting furnace,and the effects of Co co... (TiZrHf)_(50)Ni_(30)Cu_(20-x)Co_(x)(x=2,4,6,at%)high-entropy high-temperature shape memory alloys were fabricated by watercooled copper crucible in a magnetic levitation vacuum melting furnace,and the effects of Co content on microstructure and mechanical properties were investigated.The results indicate that the grain size of the alloy decreases with increasing the Co content.In the as-cast state,the alloy consists primarily of the B19′phase,with a trace of B2 phase.The fracture morphology is predominantly composed of the B19′phase,whereas the B2 phase is nearly absent.Increasing the Co content or reducing the sample dimensions(d)markedly enhance the compressive strength and ductility of the alloy.When d=2 mm,the(TiZrHf)_(50)Ni_(30)Cu_(14)Co_(6) alloy demonstrates the optimal mechanical properties,achieving a compressive strength of 2142.39±1.8 MPa and a plasticity of 17.31±0.3%.The compressive cyclic test shows that with increasing the compressive strain,the residual strain of the(TiZrHf)_(50)Ni_(30)Cu_(14)Co_(6) alloy increases while the recovery ability declines.The superelastic recovery capability of the alloy is continuously enhanced.The superelastic recovery rate increases from 1.36%to 2.12%,the residual strain rate rises from 1.79%to 5.52%,the elastic recovery rate ascends from 3.86%to 7.36%,while the total recovery rate declines from 74.48%to 63.20%. 展开更多
关键词 high-temperature shape memory alloy high-entropy alloy MICROSTRUCTURE mechanical property
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Solar-driven methane-to-ethanol conversion by “intramolecular junction” with both high activity and selectivity 被引量:1
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作者 Qijun Tang Wenguang Tu Zhigang Zou 《Chinese Journal of Structural Chemistry》 2025年第6期6-7,共2页
Methane(CH4),the predominant component of natural gas and shale gas,is regarded as a promising carbon feedstock for chemical synthesis[1].However,considering the extreme stability of CH4 molecules,it's quite chall... Methane(CH4),the predominant component of natural gas and shale gas,is regarded as a promising carbon feedstock for chemical synthesis[1].However,considering the extreme stability of CH4 molecules,it's quite challenging in simultaneously achieving high activity and selectivity for target products under mild conditions,especially when synthesizing high-value C2t chemicals such as ethanol[2].The conversion of methane to ethanol by photocatalysis is promising for achieving transformation under ambient temperature and pressure conditions.Currently,the apparent quantum efficiency(AQE)of solar-driven methane-to-ethanol conversion is generally below 0.5%[3,4].Furthermore,the stability of photocatalysts remains inadequate,offering substantial potential for further improvement. 展开更多
关键词 natural gas shale gasis target products carbon feedstock chemical synthesis howeverconsidering intramolecular junction solar driven methane ethanol conversion
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Microstructure and High-Temperature Oxidation Resistance of Cr-Al-Y Co-deposition Coating on TiAlNb9 Alloy Surface
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作者 Hao Qingrui Li Yongquan +1 位作者 Li Ning Gao Yang 《稀有金属材料与工程》 北大核心 2025年第11期2739-2748,共10页
To improve the high-temperature oxidation resistance of TiAlNb9 alloy,a Cr-Al-Y co-deposition coating was prepared on the alloy surface by the pack cementation method.The microstructure of the coating was analyzed by ... To improve the high-temperature oxidation resistance of TiAlNb9 alloy,a Cr-Al-Y co-deposition coating was prepared on the alloy surface by the pack cementation method.The microstructure of the coating was analyzed by scanning electron microscope,energy dispersive spectrometer,and X-ray diffractometer,and the high-temperature oxidation properties of the substrate and coating at 1273 K were compared and studied.The results show that the Cr-Al-Y coating is about 30μm in thickness,and it has a dense structure and good film-substrate bonding.The coating includes an outer layer composed of TiCr_(2),TiCr,Ti4Cr,and(Ti,Nb)Cr4 phases as well as an inner layer composed of Ti_(2)Al,and Nb-richγ-TiAl interdiffusion zone.The TiAlNb9 substrate forms an oxide layer composed of TiO2 and Al_(2)O_(3) at 1273 K.Due to its loose and porous structure,TiO2 oxide film cannot effectively isolate the internal diffusion of element O,resulting in continuous oxidation damage to the substrate.The Cr-Al-Y co-deposition coating forms a dense Cr2O3 and Al_(2)O_(3) oxide layer during oxidation,effectively preventing the internal diffusion of element O and significantly improving the high-temperature oxidation resistance of the substrate alloy. 展开更多
关键词 pack cementation TiAlNb9 alloy Cr-Al-Y co-deposition coating high-temperature oxidation resistance
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High-Temperature Oxidation Property and Corrosion and Wear Resistance of Laser Cladding Co-based Coatings on Pure Zr Surface
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作者 Xia Chaoqun Yang Bo +3 位作者 Liu Shuguang Zhang Bo Zhong Hua Li Qiang 《稀有金属材料与工程》 北大核心 2025年第6期1397-1409,共13页
Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,a... Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,as well as the wear resistance of the coatings.Besides,the effect of changing the laser melting process on the coatings was also investigated.The oxidation mass gain at 800–1200℃and the high-temperature oxidation behavior during high-temperature treatment for 1 h of two coated Zr alloy samples were studied.Results show that the Co coating and the Co-T800 coating have better resistance against high-temperature oxidation.After oxidizing at 1000℃for 1 h,the thickness of the oxide layer of the uncoated sample was 241.0μm,whereas that of the sample with Co-based coating is only 11.8–35.5μm.The friction wear test shows that the depth of the abrasion mark of the coated sample is only 1/2 of that of the substrate,indicating that the hardness and wear resistance of the Zr substrate are greatly improved.The disadvantage of Co-based coatings is the inferior corrosion resistance in 3.5wt%NaCl solution. 展开更多
关键词 Zr metal laser cladding Co-based coating high-temperature oxidation resistance wear resistance
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A review of 3D graphene materials for energy storage and conversion
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作者 WU Zi-yuan XU Chi-wei +2 位作者 ZENG Jin-jue JIANG Xiang-fen WANG Xue-bin 《新型炭材料(中英文)》 北大核心 2025年第3期477-518,共42页
Three-dimensional(3D)graphene monoliths are a new carbon material,that has tremendous potential in the fields of energy conversion and storage.They can solve the limitations of two-dimensional(2D)graphene sheets,inclu... Three-dimensional(3D)graphene monoliths are a new carbon material,that has tremendous potential in the fields of energy conversion and storage.They can solve the limitations of two-dimensional(2D)graphene sheets,including interlayer restacking,high contact resistance,and insufficient pore accessibility.By constructing interconnected porous networks,3D graphenes not only retain the intrinsic advantages of 2D graphene sheets,such as high specific surface area,excellent electrical and thermal conductivities,good mechanical properties,and outstanding chemical stability,but also enable efficient mass transport of external fluid species.We summarize the fabrication methods for 3D graphenes,with a particular focus on their applications in energy-related systems.Techniques including chemical reduction assembly,chemical vapor deposition,3D printing,chemical blowing,and zinc-tiered pyrolysis have been developed to change their pore structure and elemental composition,and ways in which they can be integrated with functional components.In terms of energy conversion and storage,they have found broad use in buffering mechanical impacts,suppressing noise,photothermal conversion,electromagnetic shielding and absorption.They have also been used in electrochemical energy systems such as supercapacitors,secondary batteries,and electrocatalysis.By reviewing recent progress in structural design and new applications,we also discuss the problems these materials face,including scalable fabrication and precise pore structure control,and possible new applications. 展开更多
关键词 GRAPHENE 3D network SYNTHESIS Energy storage Energy conversion
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Preparation Cu_(x)Co_(1-x)for photocatalytic conversion of CO_(2)
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作者 WANG Jingzhou YAO Chenzhong +1 位作者 ZHANG Xisheng MA Ziwei 《燃料化学学报(中英文)》 北大核心 2025年第4期462-471,共10页
Metal nanoparticles with high surface area and high electrochemical activity exhibit excellent catalytic performance in the photocatalytic reduction of carbon dioxide(CO_(2)).However,poor stability,small specific surf... Metal nanoparticles with high surface area and high electrochemical activity exhibit excellent catalytic performance in the photocatalytic reduction of carbon dioxide(CO_(2)).However,poor stability,small specific surface area,and less active sites limits its solar energy utilization.Hydrothermal method was utilized to synthesize the bimetallic material of Cu_(x)Co_(1-x)in this work.Co was loaded onto the Cu surface due to the electrons generated by the surface plasmon resonance(SPR)effect occurring on the Cu surface.Cu_(x)Co_(1-x)exhibits high photocatalytic conversion of CO_(2)efficiency under irradiation,which mainly because the Co nanoparticles on the surface of Cu can be used as cocatalysts to enhance the photocharge transfer.Cu_(0.6)Co_(0.4)exhibits the comparatively best photocatalytic conversion efficiency of CO_(2)in the first 6 h light irradiation.The yields of CO and CH_(4)reached 35.26 and 2.71μmol/(g·h),respectively.Upon illumination,electrons were produced,with the majority of them moving towards the interface.This movement contributes to the increased lifetime of photogenerated electron-hole pairs,which in turn boosts the photocatalytic efficiency.The findings of this research provide significant insights for creating photocatalysts that are both highly effective and stable in CO_(2)reduction processes. 展开更多
关键词 photocatalytic conversion hydrothermal technique surface plasmon resonance bimetallic material photoinduced charge
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Superstructured carbon materials:Progress and challenges in energy storage and conversion technologies
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作者 ZUO Ming-xue HU Xia +6 位作者 KONG De-bin WEI Xin-ru QIN Xin LV Wei YANG Quan-Hong KANG Fei-yu ZHI Lin-jie 《新型炭材料(中英文)》 北大核心 2025年第4期962-972,共11页
Carbon materials are a key component in energy storage and conversion devices and their microstructure plays a crucial role in determining device performance.However,traditional carbon materials are unable to meet the... Carbon materials are a key component in energy storage and conversion devices and their microstructure plays a crucial role in determining device performance.However,traditional carbon materials are unable to meet the requirements for applications in emerging fields such as renewable energy and electric vehicles due to limitations including a disordered structure and uncontrolled defects.With an aim of realizing devisable structures,adjustable functions,and performance breakthroughs,superstructured carbons is proposed and represent a category of carbon-based materials,characterized by precisely-built pores,networks,and interfaces.Superstructured carbons can overcome the limitations of traditional carbon materials and improve the performance of energy storage and conversion devices.We review the structure-activity relationships of superstructured carbons and recent research advances from three aspects including a precisely customized pore structure,a dense carbon network framework,and a multi-component highly coupled interface between the different components.Finally,we provide an outlook on the future development of and practical challenges in energy storage and conversion devices. 展开更多
关键词 Carbon material application Superstructured carbons Energy storage and conversion
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A new technical approach for real-time tensile strength testing of high-temperature granite based on micro-tensile testing technology
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作者 Xianzhong Li Yinnan Tian +3 位作者 Zhenhua Li Shuai Heng Xiaodong Zhang Bing Liu 《International Journal of Mining Science and Technology》 2025年第8期1323-1339,共17页
The tensile strength of rocks under real-time high-temperatures is essential for enhanced geothermal system development.However,the complex occurrence and deep burial of hot dry rocks limit the quantity and quality of... The tensile strength of rocks under real-time high-temperatures is essential for enhanced geothermal system development.However,the complex occurrence and deep burial of hot dry rocks limit the quantity and quality of standard samples for mechanical testing.This paper compared the tensile strengths obtained from Brazilian splitting tests on standard samples(with a diameter of 50 mm and a thickness of 25 mm)and micro-tensile samples(with a diameter of 50 mm and a thickness of 25 mm)of two types of granites.A power-law size effect model was established between the two sets of data,validating the reliability of the testing method.Then,miniature Brazilian splitting under real-time high-temperature,combined with X-ray diffraction(XRD)revealed temperature-dependent strength variations and microstructural damage mechanisms.The results show that:(1)The comparison error between the tensile strength obtained by the fitting model and that of the measured standard samples was less than 6%.(2)In real-time high-temperature conditions,tensile strength of granite exhibited non-monotonic behavior,increasing below 300°C before decreasing,with sharp declines at 400–500°C and 600–700°C.(3)Thermal damage stems from the differences in the high-temperature behavior of minerals,including dehydration,phase transformation,and differential expansion. 展开更多
关键词 Dry hot rock development Real-time high-temperature tensile strength Micro-tensile testing high-temperature microscopic mechanism Size effect
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