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不同比例百香果皮对发酵型全混合日粮品质和干物质消化率的影响

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饲料研究 2024年第15期47卷 19-23页

作者：吕仁龙蒋睿珂蒋博李茂周汉林高玲中国热带农业科学院热带作物品种资源研究所海南海口571101 东北农业大学动物科学技术学院黑龙江哈尔滨150030 海南博泰农业开发有限公司海南海口570000 中国热带农业科学院湛江实验站广东湛江524013

试验旨在探究不同比例百香果皮对发酵全混合日粮(FTMR)发酵品质和干物质消化率的影响。试验设定FTMR粗精比为7∶3,粗蛋白含量理论值为13%。各处理组百香果皮分别替代0(对照组,T0)、5%(T1)、10%(T2)和15%(T3)的王草。密封发酵60 d,使用... 详细信息

试验旨在探究不同比例百香果皮对发酵全混合日粮(FTMR)发酵品质和干物质消化率的影响。试验设定FTMR粗精比为7∶3,粗蛋白含量理论值为13%。各处理组百香果皮分别替代0(对照组,T0)、5%(T1)、10%(T2)和15%(T3)的王草。密封发酵60 d,使用体外瘤胃液培养方法测定干物质消化率及瘤胃发酵参数。结果表明:各处理组pH值、乙酸含量和氨态氮/总氮无显著差异(P>0.05),添加5%、10%和15%百香果皮的FTMR的乳酸含量均显著升高(P0.05)。当百香果皮添加量达到15%(T3)时,瘤胃产气量和干物质消化率均达到最高。研究表明,百香果皮可以作为发酵全日粮中的优质原料,具有促进发酵和提升干物质消化率的效果,添加量最高可达15%。

关键词：百香果皮发酵型全混合日粮干物质消化率瘤胃发酵

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《濒危语言政策与规划》评介

当代语言学 2018年第4期20卷 623-628页

作者： Mari C.jones 曾国才四川大学外国语学院

近年来，濒危语言问题不断引起语言学、社会学、政治学等多学科领域的关注。《濒危语言政策与规划》（Policy and Planning for Endangered languages）一书由***主编，2015年由剑桥大学出版社出版，展示了当前濒危语言复兴政策和规划... 详细信息

近年来，濒危语言问题不断引起语言学、社会学、政治学等多学科领域的关注。《濒危语言政策与规划》（Policy and Planning for Endangered languages）一书由***主编，2015年由剑桥大学出版社出版，展示了当前濒危语言复兴政策和规划的最新研究成果。***博士是剑桥大学法语系的高级讲师和彼得学院（Peterhouse）的研究员。她发表了大量关于诺曼第语（Norman）、威尔士语（Welsh）和布列塔尼语（Breton）的语言濒危现象研究论著，主要致力于濒危语言的复兴研究。

关键词：语言政策规划剑桥大学出版社评介濒危语言语言问题研究成果高级讲师

基于源荷匹配的梯级水风光蓄系统优化运行研究

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中国农村水利水电 2024年第3期 8-15页

作者：袁川李博李相锐张帅吕孟冉贺星棋国网四川省电力公司四川成都610041 四川大学四川成都610065 国网四川省电力公司经济技术研究院四川成都610041 四川新型电力系统研究院四川成都610041

在“双碳”目标下,我国亟需进行能源结构转型,提高可再生能源在电力系统中的比例。调节性水电站和抽蓄电站具有良好的调蓄能力,可以作为调节电源与风光电源联合运行,从前端减缓风光不稳定出力对电力系统的冲击,促进新能源集中上网消纳... 详细信息

在“双碳”目标下,我国亟需进行能源结构转型,提高可再生能源在电力系统中的比例。调节性水电站和抽蓄电站具有良好的调蓄能力,可以作为调节电源与风光电源联合运行,从前端减缓风光不稳定出力对电力系统的冲击,促进新能源集中上网消纳。因此,充分利用梯级水电站及抽水蓄能电站的调节性能,制定合理的一体化调度策略,有利于在发电侧实现水风光蓄打捆送出和协同消纳,助力“双碳”目标实现。基于对梯级水风光蓄互补发电系统在短期调度中电网侧负荷需求和梯级水电水资源利用率的考虑,构建以源荷差异最小、梯级水电蓄能增量最大为目标,以常规水电站、风光电站、抽水蓄能电站安全运行条件为约束的短期互补调度模型,并采用粒子群-动态规划内外层嵌套算法对模型进行求解。选取西南某流域常规梯级水电站、抽水蓄能电站及周边风光电站组成的水风光蓄互补发电系统为研究对象进行模拟计算,结果表明:(1)抽水蓄能电站倾向于在梯级电站水头较低时选择泄水发电,而在梯级电站水头较高时选择抽水或维持当前水位不变;(2)所构建模型有效提高了系统总出力曲线与电网负荷曲线的匹配度,实现了梯级水电站之间负荷与水量的合理分配,一定程度上减少了梯级水电站效益损耗,提高了水能利用率,增加了梯级水电蓄能增量,有利于源网协同运行和梯级电站之间的稳定运行。

关键词： “双碳”目标水风光蓄发电系统互补调度模型优化算法

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中小学生欺负问题中的性别差异的研究

心理科学 2000年第4期23卷 435-439+510-511页

作者：张文新,谷传华,王美萍,王益文,Kevin jones 山东师范大学教育系!济南 250014 山东师范大学教育系!济南 250014 山东师范大学教育系!济南 250014 山东师范大学教育系!济南 250014 University College Worcester!U.K.

本研究运用修订的Olweus欺负 /受欺负问卷对我国城乡 4 72 6名中小学生进行调查 ,考察了欺负与受欺负的性别差异问题 ,结果表明 :1 小学生和初中生受欺负的发生率不存在显著的性别差异 ,而男孩中欺负他人的比率却极显著地高于女孩 ;2 ... 详细信息

本研究运用修订的Olweus欺负 /受欺负问卷对我国城乡 4 72 6名中小学生进行调查 ,考察了欺负与受欺负的性别差异问题 ,结果表明 :1 小学生和初中生受欺负的发生率不存在显著的性别差异 ,而男孩中欺负他人的比率却极显著地高于女孩 ;2 中小学生对欺负问题的态度存在显著的性别差异 ,初中生对欺负的态度受性别和年级的交互作用的影响 ;3 中小学生不同欺负方式的发生率存在显著的性别差异 ,男生直接的身体欺负和间接欺负显著地高于女生 ,而言语欺负的性别差异并不显著。

关键词：中小学生欺负受欺负性别差异

Positive- and Zero-Sequence Impedance Estimation of YNyn0+d-Connected Main Power Transformers in Wind Power Applications

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CSEE Journal of Power and Energy Systems 2021年第1期7卷 57-65页

作者： Franklin l.Quilumba Robert E.Jimerson Ken Swift Rafael Garc´ıa with Oncor Electric Delivery Fort WorthTX 76102 USA

With the increased penetration of non-conventionalrenewable energy resources, such as wind power plants (WPPs),into the power system, a lot of interest has been placed on studyingtheir impact for system protection, planning and operationsto ensure continued reliability of the electric grid. The impactof WPPs on the grid is typically identified during generationinterconnection studies. One of the challenges faced by protectionand planning engineers, at an early stage in this process, isthat many of the studies involving these power plants must beperformed without specific data available because the equipmentis not built yet. Among all the needed data, a particular interest inthis study is placed on the positive- and zero-sequence impedancesof the main power transformer (MPT) that interconnects a windpower plant to the transmission system due to its contribution toshort-circuit current during ground faults. The most commonlyfound in practice MPT winding configurations is a high-voltagewinding in wye with neutral bushing;a low-voltage windingin wye with neutral bushing without phase shift between thesewindings, and a stabilizing tertiary winding connected in deltathat is not designed for external loading designated as YNyn0+***, this paper proposes a methodology to estimate the sequenceimpedances of YNyn0+d transformers from a statistical point ofview applying clustering and regression analyses on existing MPTtest report data.

关键词： Positive-and zero-sequence impedance estimation power transformers short-circuit analysis threewinding transformer with buried tertiary wind power integration

On large scale CFD-DEM simulation for gas-liquid-solid,three-phase flows

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Particuology 2021年第6期19卷 2-15页

作者： Kimiaki Washino Ei l.Chan Tetsushi Kaji Yoshiaki Matsuno Toshitsugu Tanaka Department of Mechanical Engineering Osaka UniversitySuitaOsaka 565-0871Japan

Particulate flows in a mixture of gas and liquid,***-liquid-solid three-phase flows,are frequently encountered both in nature and *** such flows,complex interactions between multiple phases,***-particle interactions,fluid-particle interactions and interfacial interactions(such as surface tension and particle wetting),play a crucial *** literature,simulations of three-phase flows are sometimes performed by incorporating interface capturing methods(*** method)into the CFD-DEM coupling ***,it is practically impossible to perform large(industrial)scale simulation because of the high computational *** of the strategies often employed to reduce the computational cost in CFD-DEM is to upscale particle size,which is applied mainly to particle single-phase and fluid-solid two-phase *** present work is focused on the scaled-up particle model for gas-liquid-solid three-phase *** interaction forces between multiple phases are scaled using the general criteria derived from the continuum assumption of particulate flow.A colour function based interface-capturing method with improved interface smoothness is developed,and the diffusion based coarse graining is employed to ensure sufficient space resolution in CFD even when particle size is *** is shown that the model developed is capable of predicting the both particles and fluid behaviour in the original system.

关键词： CFD-DEM Three-phase flow Scaled-up particle Surface tension and wetting

Crystallographic evidences for twin-assisted eutectic growth in undercooled Ni-18.7 at.%Sn eutectic melts

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Journal of Materials Science & Technology 2023年第4期135卷 65-79页

作者： Fan Zhang Jianbao Zhang Xinlei lü Ke Hua Yuhong Zhao Haifeng Wang State Key laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

Rapid solidification in undercooled Ni-18.7 at.%Sn eutectic melts was observed in-situ by a high-speed high-resolution camera and the microstructures were characterized in detail by electron backscattering *** the first time,the exact crystallographic orientation relations(ORs)between HCP-Ni_(3)Sn(α-Ni)subsets were *** HCP-Ni_(3)Sn,the{1121}and/or{1122}twin ORs(i.e.,HCP-Ni_(3)Sn twins)hold independently on undercooling,whereas forα-Ni,the{111}twin OR is the case at low undercooling and would hold initially at intermediate and high *** roles of twinning and allotropy transformation(i.e.,FCC-Ni_(3)Sn→HCP-Ni_(3)Sn)were integrated to reveal the formation mechanism of HCP-Ni_(3)Sn twins,and a reversed OR transition analysis was carried out for rep-resentative samples from low to high ***,novel twin-assisted eutectic growth was found to occur all *** this basis,we showed that the single nucleation mode of Herlach is followed,and speculated that primary and secondary coupled eutectic dendrite growth and un-coupled growth ofα-Ni and FCC-Ni_(3)Sn might all be the origins of anomalous *** work would shed some lights on the long-time controversies about the nucleation mode and the formation mechanism of anomalous eutectics in undercooled eutectic alloys.

关键词： Twin-assisted eutectic growth Allotropy transformation Nucleation mode Anomalous eutectics Undercooling

THEMIS observations of two substorms on February 26,2008

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Science China(Technological Sciences) 2010年第5期53卷 1328-1337页

作者： CHU XiangNing PU ZuYin CAO Xin WANG Jue V.MISHIN V.ANGElOPOUlOS lIU Jiang WEI Yong K.H.GlASSMEIER J.MCFADDEN D.lARSON S.MENDE H.FREY C.T.russell I.MANN D.SIBECK ZONG QiuGang FU SuiYan XIE lun T.I.SAIFUDINOVA M.V.TOlOCHKO l.A.SAPRONOVA H.REME E.lUCEK School of Earth and Space Sciences Peking UriiversityBeijing 100871China Institute of Solar-Terrestrial Physics Russian Academy of Sciences IGPP UCLA Instiute of Geophysics and Extraterrestrial Physics Technical University of BraunschweigBraunschweig and Max Planck Institute of Solar System Research Space Sciences laboratory University of California Department of Physics University of Alberta Code 674 NASA/GSFC Centre d'Etude Spatiale des Rayonnements Blackett laboratory Imperial College London

Two substorms occurred at ～04:05 and ～04:55 UT on February 26,2008 are studied with the in-situ observations of THEMIS satellites and ground-based aurora and magnetic field *** et *** made a comprehensive study of the 04:55 UT *** showed detailed features of the two substorms with much attention to the first event and to the rela-tionship between mid-tail magnetic reconnection(MR) and substorm *** was found that in the earlier stage of each substorm,a first auroral intensification occurred 2-3 min soon after the start of mid-tail MR,followed by a slow and very lim-ited *** auroral arcs were weak,short-lived,and localized,characterizing all features of a *** re-garded the first auroral brightening as the initial onset of the substorms.A few minutes later,a second stronger auroral intensification appeared,followed by quick and extensive *** was interesting to note that the second brightening and related poleward expansion happened almost simultaneously(within a couple of minutes) with the onset of earthward flow and dipolarization in the near-Earth tail and other phenomenon of the substorm expansion *** thus regarded the second auroral brightening as the major onset of the ***,it was seen that during the growth phase of the two substorms,the polar cap open flux Ψ kept increasing,while it quickly reduced during the substorm expansion and recovery *** variations of Ψ implied that the evolution of the two substorm expansion phases were closely related to MR of tail lobe open field *** of substorm activities revealed that the two events studied were small substorms;while estimate of MR rate indicated that the MR processes in the two substorms were *** aforementioned observations suggested that mid-tail MR initiated the pseudobreakup first;the earthward flow generated by MR transported magnetic flux and energy to the near-Earth tail to cause the formatio

关键词： substorm auroral intensification/brightening auroral expansion dipolarization magnetic reconnection

Multivariate extremes and max-stable processes:discussion of the paper by Zhengjun Zhang

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Statistical Theory and Related Fields 2021年第1期5卷 41-44页

作者： R.l.Smith Department of statistics and operations research university of north carolinachapel hillnc 27514usa

This discussion reviews the paper by Zhengjun Zhang in the context of broader research on multivariate extreme value theory and max-stable processes.

关键词： Brown-Resnick processes extreme value theory M4 processes max-stable processes maximum likelihood multivariate extremes