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农用货车在木材运输中适用性的探讨

林业勘察设计 2002年第1期22卷 100-102页

作者：叶永长大田县林业局 366100

随着市场经济的发展,长期以来使用的EQ140、CA141等较大型汽车在我省木材运输中的局限性已逐渐显露出来,文章从林区道路和经济效益的角度进行分析探讨,认为农用货车更适用于当前的林区运材作业。

关键词：木材运输农用货车林区道路林区运材行业技术参数

Spatiotemporal evolution of Ediacaran-Cambrian(ca. 551–523 Ma)sponges in South China and their simulated contributions to marine oxygenation

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Science China Earth Sciences 2025年

作者： Yan ye Lei ZHANG Can CHEN Shan chang Yuhao YI Qinglai FENG State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Wuhan) School of Earth Science China University of Geosciences(Wuhan) Department of Geology Lund University Institute of Sedimentary Geology Chengdu University of Technology Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of Technology Second Geological Brigade of Hubei Geological Bureau College of Urban and Environmental Sciences Hubei Normal University Exploration and Development Research Institute SINOPEC Jianghan Oilfield Company

The origin and evolution of sponges have attracted interest, not only because they are among the most basal metazoans, but also because they act as important ecological engineers in the ocean. Previous research suggested that sponge groups diversified quickly during the Cambrian Series 2, while Terreneuvian sponge fossils are conspicuously rare and poorly substantiated. yet, an increasing number of sponge spicules have been reported from the Ediacaran-Cambrian(E-C, ca.551–523 Ma) transitional carbonates/cherts worldwide, particularly in South China, which calls for updated discussions. Ocean oxygenation has been widely proposed to play a critical role in organismal evolution, but its relationship with sponges is unclear and falls into a “chicken-egg” dilemma. In this study, we summarize reported sponge spicule distributions from five E-C sections in South China to investigate the early evolutionary pattern of siliceous sponges. According to current stratigraphic correlation,monaxons first appear in the late Ediacaran in the intrashelf basin-slope area, and then potentially expand to the continental shelf and deep basin in the lower Cambrian. In these sections, the abundance, size, and diversity of monaxons increase upwards,followed by the appearance of diaxons, triaxons and then polyactines. Despite the uncertain affinity of the sponge fossils, it is possible that siliceous hexactinellids evolved later than siliceous demosponges, given that the earliest spicule assemblages are exclusively composed of monaxons, which commonly form bundles comparable to modern demosponges. New geochemical data from the Sifangjing section, Guizhou Province and the Yanziqiao section, Hunan Province, South China show that the appearance of sponges usually corresponds to anoxic environment. In addition, we applied the recently proposed Biological Pump, Oxygen and Phosphorus(BPOP) model to trace the evolution of oceanic oxygen concentrations with the radiation of sponges. The results indic

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米碎花种子繁殖正交试验模糊分析

种子 2014年第8期33卷 95-97页

作者：叶耀雄叶永昌黄倩琳翟欣周永东东莞市林业科学研究所广东东莞523106

采用正交试验的模糊分析方法研究了不同播种深度,浸种时间,光照强度以及培养土等因素对米碎花(Eurya chinensis)播种发芽率的影响。结果表明:米碎花播种育苗以浸种时间影响最大,其余依次为光照强度、播种深度和培养土;以混合土为培养土... 详细信息

采用正交试验的模糊分析方法研究了不同播种深度,浸种时间,光照强度以及培养土等因素对米碎花(Eurya chinensis)播种发芽率的影响。结果表明:米碎花播种育苗以浸种时间影响最大,其余依次为光照强度、播种深度和培养土;以混合土为培养土、浸种48 h、播在表土、盖1层遮阳网的发芽率最高。

关键词：米碎花种子繁殖正交试验模糊分析

Multivariate synergy for heightening ionic HOF robustness and proton conductivity

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Science China Chemistry 2025年

作者： Xiang-Tian Bai Li-Hui Cao Xu-yong Chen Jia-Yu Wang Zi-ye Zhou Shaanxi Key Laboratory of Chemical Additives for Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and Technology

Multicomponent crystalline materials construct more complex and diversified structures with different combinations and modes,which expands the material structure space and application *** this work,we have successfully synthesized two twocomponent ionic hydrogen-bonded organic frameworks （iHOF-32 and iHOF-33） and a three-component iHOF （iHOF-34）.Guanidine hydrochloride which is rich in N and H and has a short chain length strengthens the hydrogen bonding network of iHOF,thereby aiding in the efficient migration of *** rigid architecture of 1,1'-diamino-4,4'-bipyridine diiodide furnishes additional scaffolding for the iHOFs and enhances its robustness under harsh ***-34 accomplishes the combination of the ultra-high proton conductivity of iHOF-32 and the robustness of iHOF-33 by the synergistic interaction among the three components of *** addition,iHOF-34 was fabricated as a composite membrane with a peak proton conductivity of 1.55×10-1S cm-1,which is 3.8 times higher than that of recast Nafion,and has extensive potential in fuel *** self-assembly strategy of multicomponent HOFs opens up new avenues for constructing diverse structures while promising new opportunities for applications in the fields of proton conduction and energy storage.

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Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： Wei Xiong Xuan ye Hongzhang Cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

Prussian Blue Analogue‑Templated Nanocomposites for Alkali‑Ion Batteries:Progress and Perspective

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Nano-Micro Letters 2025年第1期17卷 216-261页

作者： Jian‑En Zhou Yilin Li Xiaoming Lin Jiaye ye Key Laboratory of Theoretical Chemistry of Environment Ministry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006People’s Republic of China School of Chemistry and Physics Faculty of ScienceQueensland University of Technology2 George StreetBrisbaneQLD 4000Australia Centre for Materials Science Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia

Lithium-ion batteries(LIBs)have dominated the portable electronic and electrochemical energy markets since their commercialisation,whose high cost and lithium scarcity have prompted the development of other alkali-ion batteries(AIBs)including sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs).Owing to larger ion sizes of Na^(+)and K^(+)compared with Li^(+),nanocomposites with excellent crystallinity orientation and well-developed porosity show unprecedented potential for advanced lithium/sodium/potassium *** enticing open rigid framework structures,Prussian blue analogues(PBAs)remain promising self-sacrificial templates for the preparation of various nanocomposites,whose appeal originates from the well-retained porous structures and exceptional electrochemical activities after thermal *** review focuses on the recent progress of PBA-derived nanocomposites from their fabrication,lithium/sodium/potassium storage mechanism,and applications in AIBs(LIBs,SIBs,and PIBs).To distinguish various PBA derivatives,the working mechanism and applications of PBA-templated metal oxides,metal chalcogenides,metal phosphides,and other nanocomposites are systematically evaluated,facilitating the establishment of a structure–activity correlation for these *** on the fruitful achievements of PBA-derived nanocomposites,perspectives for their future development are envisioned,aiming to narrow down the gap between laboratory study and industrial reality.

关键词： Prussian blue analogues Self-sacrificial template Lithium-ion batteries Sodium-ion batteries Potassium-ion batteries

Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 329-355页

作者： Yufeng Xing ye Yuan Gen Li Institute of Solid Mechanics Beihang University(BUAA)Beijing100191China

The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical *** taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue ***,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are *** is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.

关键词： Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method

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东莞林科园土壤养分状况分析

华南农业大学学报 2006年第2期27卷 88-91页

作者：龚弘娟苏志尧朱剑云叶永昌华南农业大学林学院广东广州510642 东莞林业科学研究所广东东莞511700

依据对东莞林科园20个土壤剖面的调查取样,用电位法、碱解扩散法、氟化氨-盐酸浸提法、乙酸铵浸提-原子吸收法、重铬酸钾氧化-远红外加热法分别测定了土壤pH、速效N、速效P、速效K和有机质.在分析土壤养分总体特征的基础上,运用系统聚... 详细信息

依据对东莞林科园20个土壤剖面的调查取样,用电位法、碱解扩散法、氟化氨-盐酸浸提法、乙酸铵浸提-原子吸收法、重铬酸钾氧化-远红外加热法分别测定了土壤pH、速效N、速效P、速效K和有机质.在分析土壤养分总体特征的基础上,运用系统聚类的方法将东莞林科园土壤划分为6种养分类型:类Ⅰ为低肥力土壤;类Ⅱ为中氮土壤;类Ⅲ为高氮低磷土壤;类Ⅳ为富有机质的缺氮缺磷土壤;类Ⅴ属富磷高氮土壤;类Ⅵ属富氮土壤.其中,前3类是林科园的主要土壤养分类型.所划分的养分类型能反映各网格单元的地形特征及土地利用方式.

关键词：土壤养分土壤肥力养分分级聚类分析

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米碎花茶扦插繁殖的正交试验模糊分析

广东农业科学 2010年第4期37卷 39-41页

作者：叶耀雄叶永昌王登良朱剑云吕浩荣东莞市林业科学研究所广东东莞523106 华南农业大学茶业科学研究所广东广州510642

采用正交试验的模糊分析方法,研究了不同插穗大小、培养基质、ABT生根剂浓度以及扦插时间等因素对米碎花茶扦插繁殖的影响。结果表明:米碎花茶扦插育苗以红壤土为培养基质、2000倍浓度的生根剂(10%可溶性粉剂)、直径为0.1cm的插穗在2月... 详细信息

采用正交试验的模糊分析方法,研究了不同插穗大小、培养基质、ABT生根剂浓度以及扦插时间等因素对米碎花茶扦插繁殖的影响。结果表明:米碎花茶扦插育苗以红壤土为培养基质、2000倍浓度的生根剂(10%可溶性粉剂)、直径为0.1cm的插穗在2月份扦插成活率最高。

关键词：米碎花茶扦插繁殖正交试验模糊分析