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“~料”、“~費”、“~代”、“~賃”接尾词的用法区分
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作者 刘梅晴 《现代语言学》 2023年第8期3553-3557,共5页
日语中有“~料”、“~費”、“~代”、“~賃”这四个近义接尾词。这四个后缀的基本意思都是“钱”。但是,在使用的时候,往往存在一定的区别。经过笔者的初步调查发现,先前的研究者关于这个课题的研究存在断层,并且研究的数量也不多。因... 日语中有“~料”、“~費”、“~代”、“~賃”这四个近义接尾词。这四个后缀的基本意思都是“钱”。但是,在使用的时候,往往存在一定的区别。经过笔者的初步调查发现,先前的研究者关于这个课题的研究存在断层,并且研究的数量也不多。因此,笔者在本文中,将在前人研究的基础上,根据这四个后缀的语源和意义,对它们的使用方法进行区分和考察。希望日语学习者在看完本文后,能够正确地区分和使用它们。 展开更多
关键词 “~料” “~費” “~代” “~賃” 接尾词 用法区分
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生物降解塑料在厨余垃圾堆肥中厌氧降解性能研究
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作者 石添超 刘旭冉 +5 位作者 卢波 季君晖 王格侠 赵宏亮 毛海梅 黄丹 《塑料包装》 CAS 2024年第5期31-35,18,共6页
选取4种典型生物降解塑料PLA、PBAT、PBS和淀粉混合物,通过自主搭建厌氧生物降解性能检测平台,进行为期290天的厨余垃圾堆肥中厌氧降解性能评估。进一步通过监测PLA、PBAT薄膜降解过程中形貌尺寸、失重、分子量和结构变化,研究了厌氧降... 选取4种典型生物降解塑料PLA、PBAT、PBS和淀粉混合物,通过自主搭建厌氧生物降解性能检测平台,进行为期290天的厨余垃圾堆肥中厌氧降解性能评估。进一步通过监测PLA、PBAT薄膜降解过程中形貌尺寸、失重、分子量和结构变化,研究了厌氧降解过程机制。研究表明4种生物降解塑料在厌氧厨余垃圾堆肥中发生不同程度降解,但矿化率变化趋势都是先快后趋于缓慢,其中PLA最快,然后是PBS和淀粉混合物,PBAT最慢,在290天后累积矿化率依次分别达到33.8%,27.3%,20.1%和12.7%。相同的是,无论PLA还是PBAT,都存在微生物酶催化氧化作用,进而促进降解;不同的是,PLA薄膜经历快速本体水解过程,而PBAT薄膜经历表面腐蚀降解过程。本工作为生物降解塑料大面积推广应用的环境安全性评价,以及回收并厌氧堆肥处理可行性提供科学依据。 展开更多
关键词 污染 生物降解塑 厨余垃圾堆肥 厌氧降解 降解装置
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复配乳液聚合物水泥防水涂料防护效果研究
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作者 吕格云 付弯弯 +4 位作者 卢雨婷 周薇 刘杰胜 彭浩 徐闫 《湖北科技学院学报》 2023年第4期140-149,共10页
本文以丙烯酸酯乳液和氯丁橡胶乳液复配的方法制备聚合物水泥防水涂料,以解决单一聚合物乳液水泥防水涂料在应用过程中易开裂、柔性不足等问题。将其涂覆于水泥砂浆试块表面,探讨了涂层对氯盐侵蚀、硫酸盐侵蚀、冻融循环、自然环境侵蚀... 本文以丙烯酸酯乳液和氯丁橡胶乳液复配的方法制备聚合物水泥防水涂料,以解决单一聚合物乳液水泥防水涂料在应用过程中易开裂、柔性不足等问题。将其涂覆于水泥砂浆试块表面,探讨了涂层对氯盐侵蚀、硫酸盐侵蚀、冻融循环、自然环境侵蚀下水泥砂浆试块质量、抗压强度的影响,分析了涂层对试块的防护效果。结果显示涂层水泥砂浆试块均无开裂、剥落现象,试块的质量损失率、抗压强度损失率均较小。采用复配乳液并添加外加剂制得涂层对水泥砂浆试块的防护效果最优,试块在氯盐、硫酸盐侵蚀180天、冻融循环100次后的抗压强度损失率分别为9.45%、10.84%、12.16%,自然环境侵蚀120天后,试块抗压强度可保持为29.80MPa远高于无涂层试块。还以其中防护效果最优配方制备聚合物水泥防水涂料,探讨了涂层涂覆方法对自然环境侵蚀下涂层水泥砂浆试块抗压强度的影响。结果显示固定涂层厚度,分多次涂覆制得涂层更致密,交叉涂覆方法制得涂层厚度更均匀,沿十字交叉方向分三次涂覆制得涂层对水泥砂浆试块的防护效果更优。 展开更多
关键词 聚合物水泥防水涂 防水涂 建筑防水 防护效果
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“报料”与“爆料”的用法差异 被引量:1
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作者 邹雪 杨文全 《语言文字应用》 CSSCI 北大核心 2004年第2期70-73,共4页
本文对“报料”和“爆料”两词的意义、用法进行了分析比较 ,并从构词语素和造词理据两方面分析了两词的差别 ,同时简单论述了两词的出现和使用是符合汉语发展和汉语规范化的要求的。
关键词 用法差异
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影响酶法回收螯虾加工下脚料中虾青素及蛋白质的因素研究 被引量:16
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作者 姜启兴 夏文水 《食品工业科技》 CAS CSCD 北大核心 2004年第7期54-56,59,共4页
通过测定螯虾加工下脚料中虾青素和蛋白质在不同保藏条件、预处理条件和酶解条件下的含量变化,研究了这些因素对酶法回收虾青素和蛋白质的影响。结果表明,破碎的下脚料在空气中保藏12d后虾青素残留仅37.5%,在阳光下照射3d虾青素残留18.... 通过测定螯虾加工下脚料中虾青素和蛋白质在不同保藏条件、预处理条件和酶解条件下的含量变化,研究了这些因素对酶法回收虾青素和蛋白质的影响。结果表明,破碎的下脚料在空气中保藏12d后虾青素残留仅37.5%,在阳光下照射3d虾青素残留18.2%,在真空、冷冻、避光的保藏条件下虾青素损失较少;酶解前预热处理蛋白质回收率可提高5%,但虾青素回收率下降5.6%;破碎后虾青素及蛋白质的回收率大幅提高,超声波处理有助于二者的回收率;酶解反应的最适条件为温度55℃,pH8.5,反应时间2h,酶底比3750U/g蛋白质。 展开更多
关键词 螯虾下脚 酶解 影响因素 虾青素 蛋白质
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“不料”与“竟(然)”辨——兼谈二词的教学 被引量:4
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作者 肖治野 《语言与翻译》 北大核心 2003年第4期27-30,57,共5页
"不料"和"竟(然)"的用法有何区别与联系?本文针对一本汉语教材中出现的对二词释义的矛盾现象,从语义、功能等方面对其进行分析比较,并对教材和教法提出一些建议。
关键词 竟然 想不到
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Microstructure and properties of Cu matrix composites reinforced with surface-modified Kovar particles
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作者 Tao MENG Ri-chu WANG +1 位作者 Zhi-yong CAI Ying-jun YAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3251-3264,共14页
The thermal conductivity of Cu/Kovar composites was improved by suppressing element diffusion at the interfaces through the formation of FeWO_(4)coating on the Kovar particles via vacuum deposition.Cu matrix composite... The thermal conductivity of Cu/Kovar composites was improved by suppressing element diffusion at the interfaces through the formation of FeWO_(4)coating on the Kovar particles via vacuum deposition.Cu matrix composites reinforced with unmodified(Cu/Kovar)and modified Kovar(Cu/Kovar@)particles were prepared by hot pressing.The results demonstrate that the interfaces of Cu/FeWO_(4)and FeWO_(4)/Kovar in the Cu/Kovar@composites exhibit strong bonding,and no secondary phase is generated.The presence of FeWO_(4)impedes interfacial diffusion within the composite,resulting in an increase in grain size and a decrease in dislocation density.After surface modification of the Kovar particle,the thermal conductivity of Cu/Kovar@composite is increased by 110%from 40.6 to 85.6 W·m^(-1)·K^(-1).Moreover,the thermal expansion coefficient of the Cu/Kovar@composite is 9.8×10^(-6)K^(-1),meeting the electronic packaging requirements. 展开更多
关键词 electronic packaging material Cu/Kovar composite surface modification thermal conductivity
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Microstructure and ablation behavior of Zr-based ultra-high-temperature gradient composites
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作者 Qing-hua LIU Tian TIAN +2 位作者 Wei SUN Hong-bo ZHANG Xiang XIONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2889-2899,共11页
To obtain high-performance Zr-based ultra-high-temperature composites,Zr-based ultra-high-temperature gradient composites were prepared by changing the laying method of the infiltrant via reactive melt infiltration.Th... To obtain high-performance Zr-based ultra-high-temperature composites,Zr-based ultra-high-temperature gradient composites were prepared by changing the laying method of the infiltrant via reactive melt infiltration.The effects of different infiltrant laying methods on the microstructure and ablative properties of Zr-based ultrahigh-temperature gradient composites were investigated.The results showed that the gradient structure of the Zr-based ultrahigh-temperature gradient composites differed when the composition ratio of the infiltrant was changed.When the thicknesses of the Zr/Mo/Si layers were 6/4/12 mm and 8/2/12 mm,the SiMoZrC solid solution content in the samples increased and decreased along the infiltration direction,respectively.The gradient samples were ablated in an oxyacetylene flame at 3000°C for 40 s.The ablation resistance of the sample was the highest when the infiltrant was a powder and the thickness of the Zr/Mo/Si layer was 6/4/12 mm. 展开更多
关键词 reactive melt infiltration ceramic-matrix composites gradient material MICROSTRUCTURE ablation property
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Evolution of microstructure and mechanical properties in multi-layer 316L-TiC composite fabricated by selective laser melting additive manufacturing
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作者 Sasan YAZDANI Suleyman TEKELI +2 位作者 Hossein RABIEIFAR Ufuk TASCI Elina AKBARZADEH 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期2973-2991,共19页
In this study,the microstructure and mechanical properties of a multi-layered 316L-TiC composite material produced by selective laser melting(SLM)additive manufacturing process are investigated.Three different layers,... In this study,the microstructure and mechanical properties of a multi-layered 316L-TiC composite material produced by selective laser melting(SLM)additive manufacturing process are investigated.Three different layers,consisting of 316L stainless steel,316L-5 wt%TiC and 316L-10 wt%TiC,were additively manufactured.The microstructure of these layers was characterized by optical microscopy(OM)and scanning electron microscopy(SEM).X-ray diffraction(XRD)was used for phase analysis,and the mechanical properties were evaluated by tensile and nanoindentation tests.The microstructural observations show epitaxial grain growth within the composite layers,with the elongated grains growing predominantly in the build direction.XRD analysis confirms the successful incorporation of the TiC particles into the 316L matrix,with no unwanted phases present.Nanoindentation results indicate a significant increase in the hardness and modulus of elasticity of the composite layers compared to pure 316L stainless steel,suggesting improved mechanical properties.Tensile tests show remarkable strength values for the 316L-TiC composite samples,which can be attributed to the embedded TiC particles.These results highlight the potential of SLM in the production of multi-layer metal-ceramic composites for applications that require high strength and ductility of metallic components in addition to the exceptional hardness of the ceramic particles. 展开更多
关键词 multilayer metal-ceramic composites selective laser melting functionally graded materials 316 L stainless steel TIC
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Corrosion behavior of co-gasification slag of furfural residue and coal on alumina-silica refractories
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作者 MA Xiaotong WANG Zhigang +8 位作者 LU Hao LIU Wei WANG Yanxia ZHAO Jiangshan SUN Lingmin YAN Jingchong ZHUANG Shujuan LI Huaizhu KONG Lingxue 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第10期1387-1397,共11页
Gasification of furfural residue with coal can realize its efficient and clean utilization.But the high alkali metal content in furfural slag is easy to cause the corrosion of gasifier refractory.Two gasification coal... Gasification of furfural residue with coal can realize its efficient and clean utilization.But the high alkali metal content in furfural slag is easy to cause the corrosion of gasifier refractory.Two gasification coals with different silica alumina ratio and a furfural residue were selected in the study.The effects of furfural residue additions on corrosion of silica brick,corundum brick,high alumina brick and mullite brick were investigated by using XRD,SEM-EDS and Factsage Software,and the corrosion mechanism was analyzed.With increasing furfural residue addition,the permeability of the slags to high-aluminium-bearing refractories first decreases and then increases,while the permeability on silica brick shows a slight decrease trend.Leucite(KAlSi_(2)O_(6))with high-melting temperature is generated from the reaction of K_(2)O and SiO_(2)in slag with Al_(2)O_(3)in refractories after furfural residue is added,which hinders the infiltration of slag in refractories.Kaliophilite(KAlSiO_(4))of low-melting point is formed when K_(2)O content increases,and this contributes to the infiltration of slag in refractories.The acid-base reaction between slag and silica brick is distinctly occurred,more slag reacts with SiO_(2)in the silicon brick,resulting in a decrease in the amount of slag infiltrating into the silicon brick as furfural residue is added.The corrosion of silica brick is mainly caused by the acid-base reaction,while the corrosion of three alumina based refractory bricks of corundum,mullite and high alumina brick is determined by slag infiltration.A linear correlation between the percolation rate and slag viscosity is established,the slag permeability increases with decreasing viscosity,resulting in stronger permeability for the high Si/Al ratio slag with lower viscosity. 展开更多
关键词 furfural residue CO-GASIFICATION SLAG REFRACTORY corrosion
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Design,progress and challenges of 3D carbon-based thermally conductive networks
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作者 JING Yuan LIU Han-qing +2 位作者 ZHOU Feng DAI Fang-na WU Zhong-shuai 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期844-871,共28页
The advent of the 5G era has stimulated the rapid development of high power electronics with dense integration.Three-dimensional(3D)thermally conductive networks,possessing high thermal and electrical conductivities a... The advent of the 5G era has stimulated the rapid development of high power electronics with dense integration.Three-dimensional(3D)thermally conductive networks,possessing high thermal and electrical conductivities and many different structures,are regarded as key materials to improve the performance of electronic devices.We provide a critical overview of carbonbased 3D thermally conductive networks,emphasizing their preparation-structure-property relationships and their applications in different scenarios.A detailed discussion of the microscopic principles of thermal conductivity is provided,which is crucial for increasing it.This is followed by an in-depth account of the construction of 3D networks using different carbon materials,such as graphene,carbon foam,and carbon nanotubes.Techniques for the assembly of two-dimensional graphene into 3D networks and their effects on thermal conductivity are emphasized.Finally,the existing challenges and future prospects for 3D carbon-based thermally conductive networks are discussed. 展开更多
关键词 Carbon material 3D network GRAPHENE Thermal conductivity Heat transfer
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Research progress of permanent ferrite magnet materials
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作者 XU Bin CHEN Yu-feng +3 位作者 ZHOU Yu-juan LUO Bi-yun ZHONG Shou-guo LIU Xing-ao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期1723-1762,共40页
Permanent ferrite magnet materials are extensively employed due to their exceptional magnetic properties and cost-effectiveness.The fast development in electromobile and household appliance industries contributes to a... Permanent ferrite magnet materials are extensively employed due to their exceptional magnetic properties and cost-effectiveness.The fast development in electromobile and household appliance industries contributes to a new progress in permanent ferrite materials.This paper reviews the deveolpement and progress of permanent ferrite magnet industry in recent years.The emergence of new raw material,the advancement of perparation methods and manufacturing techniques,and the potential applications of permanent ferrite materials are introduced and discussed.Specifically,nanocrystallization plays a crucial role in achieving high performance at a low cost and reducing reliance on rare earth resources,and therefore it could be a promising development trendency. 展开更多
关键词 permanent ferrite magnetic materials HIGH-PERFORMANCE nanosizing
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Numerical study of directional heat transfer in composite materials via controllable carbon fiber distribution
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作者 SHI Lei HUANG Cun-wen +5 位作者 YE Jian-ling WEN Shuang LIU Su-ping LI Fen-qiang ZHOU Tian SUN Zhi-qiang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期1945-1955,共11页
Carbon fiber reinforced polyamide 12(CF/PA12),a new material renowned for its excellent mechanical and thermal properties,has drawn significant industry attention.Using the steady-state research to heat transfer,a ser... Carbon fiber reinforced polyamide 12(CF/PA12),a new material renowned for its excellent mechanical and thermal properties,has drawn significant industry attention.Using the steady-state research to heat transfer,a series of simulations to investigate the heat transfer properties of CF/PA12 were conducted in this study.Firstly,by building two-and three-dimensional models,the effects of the porosity,carbon fiber content,and arrangement on the heat transfer of CF/PA12 were examined.A validation of the simulation model was carried out and the findings were consistent with those of the experiment.Then,the simulation results using the above models showed that within the volume fraction from 0% to 28%,the thermal conductivity of CF/PA12 increased greatly from 0.0242 W/(m·K)to 10.8848 W/(m·K).The increasing porosity had little influence on heat transfer characteristic of CF/PA12.The direction of the carbon fiber arrangement affects the heat transfer impact,and optimal outcomes were achieved when the heat flow direction was parallel to the carbon fiber.This research contributes to improving the production methods and broadening the application scenarios of composite materials. 展开更多
关键词 heat transfer thermal conductivity carbon fiber-based composite
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Is platinum-loaded titania the best material for dye-sensitized hydrogen evolution under visible light?
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作者 Haruka Yamamoto Langqiu Xiao +5 位作者 Yugo Miseki Hiroto Ueki Megumi Okazaki Kazuhiro Sayama Thomas E.Mallouk Kazuhiko Maeda 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期124-132,共9页
A dye-sensitized photocatalyst combining Pt-loaded TiO_(2) and Ru(Ⅱ)tris-diimine sensitizer(RuP)was constructed and its activity for photochemical hydrogen evolution was compared with that of Pt-intercalated HCa_(2)N... A dye-sensitized photocatalyst combining Pt-loaded TiO_(2) and Ru(Ⅱ)tris-diimine sensitizer(RuP)was constructed and its activity for photochemical hydrogen evolution was compared with that of Pt-intercalated HCa_(2)Nb_(3)O_(10) nanosheets.When the sacrificial donor ethylenediaminetetraacetic acid(EDTA)disodium salt dihydrate was used,RuP/Pt/TiO_(2) showed higher activity than RuP/Pt/HCa_(2)Nb_(3)O_(10).In contrast,when NaI(a reversible electron donor)was used,RuP/Pt/TiO_(2) showed little activity due to back electron transfer to the electron acceptor(I_(3)-),which was gener-ated as the oxidation product of I-.By modification with anionic polymers(sodium poly(styrenesulfonate)or sodium polymethacrylate)that could inhibit the scavenging of conduction band electrons by I_(3)-,the H_(2) production activity from aqueous NaI was improved,but it did not exceed that of RuP/Pt/HCa_(2)Nb_(3)O_(10).Transient absorption measurements showed that the rate of semiconductor-to-dye back electron transfer was slower in the case of TiO_(2) than HCa_(2)Nb_(3)O_(10),but the electron transfer reaction to I3-was much faster.These results indicate that Pt/TiO_(2) is useful for reactions with sacrificial reductants(e.g.,EDTA),where the back electron transfer reaction to the more reducible product can be neglected.However,more careful design of the catalyst will be nec-essary when a reversible electron donor is employed. 展开更多
关键词 Artificial photosynthesis Solar fuel Water splitting Z-scheme
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The preparation and properties of N-doped carbon materials and their use for sodium storage
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作者 YUAN Ren-lu HOU Ruo-yang +4 位作者 SHANG Lei LIU Xue-wei LI Ang CHEN Xiao-hong SONG Huai-he 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期770-795,共26页
Defect engineering by heteroatom doping gives carbon materials some new characteristics such as a different electronic structure and a high electrochemical activity,making them suitable for high-performance applicatio... Defect engineering by heteroatom doping gives carbon materials some new characteristics such as a different electronic structure and a high electrochemical activity,making them suitable for high-performance applications.N-doping has been widely investigated because of its similar atom radius to carbon,high electronegativity as well as many different configurations.We summarize the preparation methods and properties of N-doped carbon materials,and discuss their possible use in sodium ion storage.The relationships between N content/configuration and crystallinity,electronic conductivity,wettability,chemical reactivity as well as sodium ion storage performance are discussed. 展开更多
关键词 N-doped carbon material N configuration Preparation method Performance Sodium storage
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Selenga River human dispersal path in Initial Upper Paleolithic
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作者 Evgeny P RYBIN Arina M KHATSENOVICH 《人类学学报》 CSSCI CSCD 北大核心 2024年第5期780-796,共17页
Here,we consider earlier Upper Paleolithic sites in the Selenga River Basin,the main fluvial input of Lake Baikal that flows through northern Mongolia and the southwestern Transbaikal region of Russia.Lithic industrie... Here,we consider earlier Upper Paleolithic sites in the Selenga River Basin,the main fluvial input of Lake Baikal that flows through northern Mongolia and the southwestern Transbaikal region of Russia.Lithic industries from these sites can be attributed to the laminar Initial Upper Paleolithic(IUP)technocomplex,widespread in southern Siberia and Central Asia.IUP industries appear in the Selenga Basin about 45 kaBP cal.Aspects of regional typological variability and the transport of exotic raw materials over long distances indicate that these populations participated in developed exchange networks and employed high mobility targeting the acquisition of necessary raw materials.Two site types are present:quarry-workshops in northern Mongolia and generalized activity settlements in the southwestern Transbaikal.Although faunal data are limited,we interpret available information as indicating a specialization on hunting,focusing on migrating steppe game species.The distribution of sites in the mid-altitudes and landscapes of the Selenga-Orkhon geographical region and the geomorphological homogeneity of this territory also supported interregional human moves during the IUP. 展开更多
关键词 Central Asia Initial Upper Paleolithic MIGRATION raw material HUNTING
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A review of anode materials for sodium ion batteries
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作者 Syed Ali Riza XU Ri-gan +6 位作者 LIU Qi Muhammad Hassan YANG Qiang MU Dao-bin LI Li WU Feng CHEN Ren-jie 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期743-769,共27页
Lithium-ion batteries(LIBs)are used in electric vehicles and portable smart devices,but lithium resources are dwindling and there is an increasing demand which has to be catered for.Sodium ion batteries(SIBs),which ar... Lithium-ion batteries(LIBs)are used in electric vehicles and portable smart devices,but lithium resources are dwindling and there is an increasing demand which has to be catered for.Sodium ion batteries(SIBs),which are less costly,are a promising replacement for LIBs because of the abundant natural reserves of sodium.The anode of a SIB is a necessary component of the battery but is less understood than the cathode.This review outlines the development of various types of anodes,including carbonbased,metallic and organic,which operate using different reaction mechanisms such as intercalation,alloying and conversion,and considers their challenges and prospects.Strategies for modifying their structures by doping and coating,and also modifying the solid electrolyte interface are discussed.In addition,this review also discusses the challenges encountered by the anode of SIBs and the solutions. 展开更多
关键词 Sodium ion batteries ANODE Carbon material Metallic compound ORGANIC
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Nitrogen⁃doped 3D graphene⁃carbon nanotube network for efficient lithium storage
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作者 XIE Jie XU Hongnan +3 位作者 LIAO Jianfeng CHEN Ruoyu SUN Lin JIN Zhong 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期1840-1849,共10页
A 3D nitrogen⁃doped graphene/multi⁃walled carbon nanotube(CS⁃GO⁃NCNT)crosslinked network mate⁃rial was successfully synthesized utilizing chitosan and melamine as carbon and nitrogen sources,concomitant with the incor... A 3D nitrogen⁃doped graphene/multi⁃walled carbon nanotube(CS⁃GO⁃NCNT)crosslinked network mate⁃rial was successfully synthesized utilizing chitosan and melamine as carbon and nitrogen sources,concomitant with the incorporation of multi⁃wall carbon nanotubes and employing freeze drying technology.The material amalgamates the merits of 1D/2D hybrid carbon materials,wherein 1D carbon nanotubes confer robustness and expedited elec⁃tron transport pathways,while 2D graphene sheets facilitate rapid ion migration.Furthermore,the introduction of nitrogen heteroatoms serves to furnish additional active sites for lithium storage.When served as an anode material for lithium⁃ion batteries,the CS⁃GO⁃NCNT electrode delivered a reversible capacity surpassing 500 mAh·g^(-1),mark⁃edly outperforming commercial graphite anodes.Even after 300 cycles at a high current density of 1 A·g^(-1),it remained a reversible capacity of up to 268 mAh·g^(-1). 展开更多
关键词 GRAPHENE carbon nanotube hybrid material ANODE lithium⁃ion battery
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农业强国背景下畜牧业循环经济发展的创新路径研究
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作者 丁玮 《饲料研究》 CAS 北大核心 2024年第16期191-194,共4页
畜牧业循环经济发展是我国农业经济发展的重要动力来源。农业强国背景下,畜牧业循环经济发展对实现农民增收致富、改善农村生态环境、解决农业资源约束问题具有重要意义。文章从畜牧业产业结构不断优化、资源利用水平日益提升、绿色循... 畜牧业循环经济发展是我国农业经济发展的重要动力来源。农业强国背景下,畜牧业循环经济发展对实现农民增收致富、改善农村生态环境、解决农业资源约束问题具有重要意义。文章从畜牧业产业结构不断优化、资源利用水平日益提升、绿色循环发展格局初步形成三方面阐述发展畜牧业循环经济的基础。在此基础上,立足农业强国背景,提出“理念为先,推动畜牧业可持续发展;价值为要,助力畜牧循环经济稳步增长;科技为核,驱动畜牧业科技创新融合”的创新路径,以期为畜牧业循环经济高质量发展提供参考。 展开更多
关键词 农业强国 循环经济 畜牧业 可持续发展
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Experimental and numerical investigations on acoustic damping of monoclinic crystalline wideband sound absorbing structures
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作者 XIE Su-chao HE Lei +3 位作者 YAN Hong-yu ZHANG Feng-yi HE Guan-di WANG Jia-cheng 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期1931-1944,共14页
In order to overcome the limitations of traditional microperforated plate with narrow sound absorption bandwidth and a single structure,two multi-cavity composite sound-absorbing materials were designed based on the s... In order to overcome the limitations of traditional microperforated plate with narrow sound absorption bandwidth and a single structure,two multi-cavity composite sound-absorbing materials were designed based on the shape of monoclinic crystals:uniaxial oblique structure(UOS)and biaxial oblique structure(BOS).Through finite element simulation and experimental research,the theoretical models of UOS and BOS were verified,and their sound absorption mechanisms were revealed.At the same time,the influence of multi-cavity composites on sound absorption performance was analyzed based on the theoretical model,and the influence of structural parameters on sound absorption performance was discussed.The research results show that,in the range of 100-2000 Hz,UOS has three sound absorption peaks and BOS has five sound absorption peaks.The frequency range of the half-absorption bandwidth(α>0.5)of UOS and BOS increases by 242% and 229%,respectively.Compared with traditional microperforated sound-absorbing structures,the series and parallel hybrid methods significantly increase the sound-absorbing bandwidth of the sound-absorbing structure.This research has guiding significance for noise control and has broad application prospects in the fields of transportation,construction,and mechanical design. 展开更多
关键词 monoclinic crystal microperforated plate acoustic metamaterials inclined cavity sound absorption
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