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Rational design of Mns nanoparticles anchored on N,s-codoped carbon matrix as anode for lithium-ion batteries

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Progress in Natural science:Materials International 2021年第5期31卷 649-655页

作者： Weiqin Li Mengyuan Yue Huinan Guo Zhaoxia Yuan Yafei Liu Kai Chen Juming Gu Yijing Wang Key Laboratory of Advanced Energy Materials Chemistry Ministry of Education Renewable Energy Conversion and Storage Center College of Chemistry Nankai University Quick Gem Optoelectronic s and t Co. Ltd.

the manganese sulfide(Mns) has attracted more attention as anode material on energy storage and conversion field, owing to its high theoretical capacity(616 mA h g-1) and good electrochemical activity. However, low electronic conductivity and large volume expansion during charge-discharge processes have limited its further application. In order to address above mentioned problems, the composites, Mns nanoparticles embedded in N,scodoped porous carbon skeleton(named as Mns/N,s–C composites), herein have been prepared successfully using metal organic framework(Mn-NtA) as template. the porous carbon skeleton not only can enhance electrode conductivity, but also relieve volume expansion during charge-discharge processes. thus, the rational design towards electrode architectures has endowed Mns/N,s–C nanocomposites with superior electrochemical performance, which delivers the specific capacities of 676.7 mA h g-1at the current density of 100 mA g-1.

关键词： N,s-codoped Mns Nanocomposites Rods-like Lithium ion batteries

Cooling Curve's Effect on Hardening Behavior of steel

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材料热处理学报 2004年第5期25卷 462-464页

作者： Kazuto Fukuhara shigeru Asada Yoshihiro tomita syusaku Maeda Nippon Grease Co. Ltd. Osaka JapanNippon Grease Co. Ltd. Osaka JapanNippon Grease Co. Ltd. Osaka JapanNippon Grease Co. Ltd. Osaka Japan

Quenching Oils are comprised mostly of mineral oil as major component, but mineral oil alone result in lower cooling performance. therefore, various additives are formulated as required for each particular case. Cooling curves of mineral oil as determined by JIs method can be divided into three stages, vapor film stage, boiling stage and convection stage. And there are many types of additives used for quenching oil, one effective to shorten vapor film stage and another to shift boiling stage toward lower temperature side. As rapid quenching required temperature range for particular steel varies pending on its shape of CCt curve"1, it is possible to provide higher quench hardening performance using quenching oil formulated of adequate additives.

关键词：淬火油冷却效果硬化性能钢

Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

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traditional Medicine Research 2025年第1期10卷 73-81页

作者： Xiao-Long Zhou Wei-Jin Jiang Ji Yu Mao-Jun Yao Yun-tong Li Hunan Provincial Key Laboratory of Research Resource Mining and High-valued Utilization on Edible&Medicinal PlantCollege of Chemistry and Chemical EngineeringJishou UniversityJishou 416000China Hunan Gaoge dairy Co. Ltd.Changsha 410000China

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in *** vine tea processing,a large amount of broken tea is produced,which has low commercial ***:this study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(dMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea ***:A notable influence of extraction temperature on the yield of vine tea extracts(Pth BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the dMY content of the extracts(Ps dMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid *** chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted ***,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE *** vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest dPPH scavenging rate,URE leading in ABts•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant ***:the findings suggest that extraction methods signi

关键词： vine tea dihydromyricetin ultrasonic-assisted extraction volatile aroma components

single-step thermal carburization synthesis of supported molybdenum carbides from molybdenum-containing methyl-silica

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Journal of Natural Gas Chemistry 2011年第3期20卷 271-280页

作者： Juan Zou Minglin Xiang Bo How dong Wu Yuhan sun Hunan Changling Petrochemical s＆t developing Co. ltd. Yueyang 414012 Hunan China state Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi China

A novel synthesis route to obtain highly dispersed molybdenum carbides in porous silica is described. the synthesis was carried out by a single-step heat treatment of molybdenum-containing and methyl-modified silica （Mo-M-siO2） in argon atmosphere at 973 K. Mo-M-siO2 precursor was facilely obtained via a one-pot synthesis route, using （NH4）6Mo7O24 4H2O （AHM） as molybdenum sources and polymethylhydrosiloxane （PMHs） as silica sources at the initial synthetic step. the optimal C/Mo molar ratio in reaction system for complete carburization of molybdenum species was 7. the carburization process of molybdenum species followed a nontopotactic route involving a MoO2 intermediate phase, which was evidenced by XRd, N2 adsorption-desorption and in situ XPs. Formation mechanism of Mo-M-siO2 precursor was also proposed by observation of the reaction between AHM and PMHs with tEM. Furthermore, by adding tEOs into silica sources and adjusting tEOs/PMHs mass ratio, crystal phase of molybdenum carbides transferred from β-Mo2C to α-MoC1-x, and siO2 structure changed from microporous to micro/mesoporous. Catalytic performances of samples were tested using CO hydrogenation as a probe reaction. the supported molybdenum carbides exhibited high selectivity for higher alcohol synthesis compared with bulk β-Mo2C and α-MoC1-x.

关键词： molybdenum carbides porous silica single-step carburization one-pot synthesis CO hydrogenation

thrust estimate method of an on-orbit Hall thruster using Hall drift current

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Plasma science and technology 2024年第12期26卷 150-159页

作者： Ziying REN Liqiu WEI Zexin LIU Yanlin HU Liang HAN Hong LI Yongjie dING Xiufeng ZHONG school of Energy science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China Chang Guang satellite technology Co. Ltd.Changchun 130000People’s Republic of China Beijing Institute of Control Engineering Beijing 100190People’s Republic of China Beijing sunWise space technology ltd. Beijing 101300People’s Republic of China

In order to realize the thrust estimation of the Hall thruster during its flight mission,this study establishes an estimation method based on measurement of the Hall drift *** this method,the Hall drift current is calculated from an inverse magnetostatic problem,which is formulated according to its induced magnetic flux density detected by sensors,and then the thrust is estimated by multiplying the Hall drift current with the characteristic magnetic flux density of the thruster *** addition,a three-wire torsion pendulum micro-thrust measurement system is utilized to verify the estimate values obtained from the proposed *** errors were found to be less than 8%when the discharge voltage ranged from 250 v to 350 v and the anode flow rate ranged from 30 sccm to 50 sccm,indicating the possibility that the proposed thrust estimate method could be practically ***,the measurement accuracy of the magnetic flux density is suggested to be lower than 0.015 mt and improvement on the inverse problem solution is required in the future.

关键词： thrust estimation Hall effect thruster Hall drift current inverse problem tikhonov regularization

Accelerated Gas Carburizing (URX Gas Carburizing)

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材料热处理学报 2004年第5期25卷 378-381页

作者： Yoshikazu shimosato Mamoru Kamitani Hiroyuki Nakatsu Chugai Ro Co. Ltd. Osaka JapanChugai Ro Co. Ltd. Osaka JapanChugai Ro Co. Ltd. Osaka Japan

URX gas Carburizing is an accelerated gas Carburizing method with 50% CO + 50% H2 gas which comes from CFLt gas + CO2 gas. By using this gas composition, the Carburizing reaction rate increases to the maximum and the controllability of carbon potential improves. A carbon mass flow rate is the product of the Carburizing reaction rate multiplied by the difference of carbon percent between carbon potential of the gas and the carbon content of the surface of treated steel parts. We have obtained excellent results from the experimental tests at our laboratory as mentioned bellow. 1) Carburizing time can be shortened by 40% for 0.5 - 0.9 mm effective case depth. 2) Uniform Carburizing case depth 3) Less internal oxidation with the same case depth. We have already developed the new roller hearth type continuous Carburizing furnace and the new URX gas generator .

关键词：气体渗碳内部氧化质量流速反应速率系数

Fabricating functionally graded Fe-Cr-Co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and steel Research International 2024年第3期31卷 729-737页

作者： Ya-zhou He Ya-qing Hou Peng shen Hao Zhang dong Zhou Hang su Central Iron and steel Research Institute Co. Ltd.Beijing 100081China Material digital R&d Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and *** graded Fe-Cr-Co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and Co *** effects of different Fe,Cr and Co contents on the microstructure,magnetic properties and hardness of Fe-Cr-Co alloys prepared by LPBF were *** as-built Fe-Cr-Co alloys present a single body-centered-cubic phase and have a homogeneous distribution of *** mechanical properties and magnetic properties of the compositionally graded sample show a gradient *** the increase in Cr content,the vickers hardness of the sample increases,and the saturation magnetization of the sample *** optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 t and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder *** in-situ alloying technology has the potential to further explore Fe-Cr-Co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-Co alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property

Beginning from the end:the presynaptic terminal as a pathomechanism hub in frontotemporal dementia and amyotrophic lateral sclerosis

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Neural Regeneration Research 2025年第11期20卷 3217-3218页

作者： Laura Huggon Emma L.Clayton UK dementia Research Institute at King’s College London LondonUK department of Basic and Clinical Neuroscience Institute of Psychiatry Psychology&NeuroscienceKing’s College LondonLondonUK

Frontotemporal dementia and amyotrophic lateral sclerosis:Frontotemporal dementia(F t d)and amyo t rophic lateral sclerosis(ALs)are neurodegenerative diseases with significant overlapping *** these neurodegenerative diseases affect different neuronal populations(with Ftd affecting neurons of the frontal and temporal lobes,and ALs affecting upper and lower motor neurons),these two diseases are complexly *** and ALs exist on a disease spectrum,with shared genetic causes,clinical presentations,and pathologies.

关键词： diseases amyotrophic sclerosis

Mantle transects in Africa According to data of Mantle Xenocrysts and diamond Inclusions

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Acta Geologica sinica(English Edition) 2021年第S1期95卷 15-17页

作者： Igor v.AsHCHEPKOv vladimir N.ZINCHENKO Alexandr s.IvANOv v.s.sobolev Institute of Geology and Mineralogy sB RAs Novosibirsk 630090Russia CAtOCA Mining society СatocaMoscow 127473Russia ALROsA ltd. Mirny 678174Russia

We designed the mantle transects using the PtXFO2 diagrams(Ashchepkov et al.,2010,2013,2017)constructed(Figs.1 a–c)for mantle columns beneath kimberlite and sections of the lithospheric mantle(sCLM)under the Kaapvaal... 详细信息

关键词： mantle lithosphere craton transect monomineral thermobarometry oxygen fugacity peridotite eclogite garnet clinopyroxene