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Valley-Chiral Edge States of Antisymmetric Plate Wave in Phononic Crystals with Linear Defect

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Acta Mechanica Solida Sinica 2021年第6期34卷 810-819页

作者： Jinfeng Zhao weitao yuan Fan Yang Zheng Zhong School of Aerospace Engineering and Applied Mechanics Tongji University100 Zhangwu RoadShanghai200092China School of Science Harbin Institute of TechnologyShenzhen518055China

In this work,two typical interfaces are established for the antisymmetric plate wave by introducing linear defect in between phononic crystals with opposite valley Hall *** evolution of projected curves is demonstrated as the defect width increases,which magnifies the occurrence of multiple edge states on both *** mapping of transmission coefficient is obtained upon the incidence of transversely symmetric and antisymmetric sources,*** is shown that the first edge state contains only symmetric or antisymmetric component regardless the defect width modulation,while other edge states contain both *** void cavity occurs on the interfaces,the mapping of transmission coefficient shows that the first edge state is topologically protected and its transverse symmetry or antisymmetry is almost unperturbed by the void cavity,while other edge states do not perform the same *** work provides useful guidance for the design of topological edge states,and bridges the topological edge states and linear defect modes on the same interface.

关键词： Topological edge state Valley Transverse symmetry Plate wave

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两株耐热有机质降解芽孢杆菌分离鉴定

饲料工业 2024年第13期45卷 112-120页

作者：袁伟涛张婷马翠柳王凯英刘晗璐中国农业科学院特产研究所特种动物饲养及综合利用创新中心吉林省特种动物微生物饲料工程研究中心吉林长春130112 赤峰学院内蒙古赤峰024000

试验旨在筛选得到耐高温可降解多种有机质的芽孢杆菌。在中国农业科学院特产研究所左家试验基地采集貉子粪堆样,经富集培养后在高温条件下分离得到两株芽孢杆菌,通过形态学鉴定、生理生化试验、16S rRNA测序分析确定分离株种属,并对分... 详细信息

试验旨在筛选得到耐高温可降解多种有机质的芽孢杆菌。在中国农业科学院特产研究所左家试验基地采集貉子粪堆样,经富集培养后在高温条件下分离得到两株芽孢杆菌,通过形态学鉴定、生理生化试验、16S rRNA测序分析确定分离株种属,并对分离菌株进行生长曲线、抗逆性、耐药性和有机质分解测试。结果表明:两株芽孢杆菌分别为解硫胺素芽孢杆菌(ZJFD007)和暹罗芽孢杆菌(ZJFD011),具有较好的生长性能、耐高温和蛋白质水解能力,其中暹罗芽孢杆菌表现出对pH变化的适应性、耐盐以及水解蛋白质、淀粉、纤维素的能力,药敏试验显示,两株分离株均对多黏菌素B耐药,解硫铵素芽孢杆菌还对丁胺卡那、卡那霉素耐药,暹罗芽孢杆菌还对青霉素、氨苄西林、哌拉西林和呋喃唑酮具耐药性。表明两株芽孢杆菌在制备有机废弃物降解高效复合菌剂上,具有良好的应用前景和经济价值。

关键词：芽孢杆菌菌株分离鉴定耐热有机质降解

Lifting scheme of symmetric tight wavelets frames

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Science in China(Series F) 2008年第8期51卷 1117-1124页

作者： ZHUANG BoJin yuan weitao PENG LiZhong Laboratory of Mathematics and Applied Mathematics School of Mathematical Sciences Peking UniversityBeijing 100871 China

This paper proposes a method to realize the lifting scheme of tight frame wavelet filters. As for 4-channel tight frame wavelet filter, the tight frame transforms＇ matrix is 2×4, but the lifting scheme transforms＇ matrix must be 4×4. And in the case of 3-channel tight frame wavelet filter, the transforms＇ matrix is 2×3, but the lifting scheme transforms＇ matrix must be 3×3. In order to solve this problem, we introduce two concepts： transferred polyphase matrix for 4-channel filters and transferred unitary matrix for 3-channel filters. The transferred polyphase matrix is symmetric/antisymmetric. Thus, we use this advantage to realize the lifting scheme.

关键词： lifting scheme tight frame wavelet transform

维生素D_(3)对10~12月龄梅花鹿生长性能、营养物质表观消化率及血清生化指标的影响

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中国畜牧兽医 2024年第10期51卷 4336-4342页

作者：张婷黄姚袁伟涛郭肖兰王凯英徐超中国农业科学院特产研究所长春130112

【目的】探究饲粮维生素D_(3)(VD_(3))添加水平对10~12月龄梅花鹿生长性能、营养物质表观消化率及血清生化指标的影响。【方法】选取24头10月龄、平均体重为(45.32±5.23)kg的健康雄性梅花鹿,随机分成4组,每组6头,每个重复1头,分别饲喂... 详细信息

【目的】探究饲粮维生素D_(3)(VD_(3))添加水平对10~12月龄梅花鹿生长性能、营养物质表观消化率及血清生化指标的影响。【方法】选取24头10月龄、平均体重为(45.32±5.23)kg的健康雄性梅花鹿,随机分成4组,每组6头,每个重复1头,分别饲喂在基础饲粮中添加0(对照组)、2000、4000和8000 IU/kg VD_(3)的试验饲粮。试验期共90 d。试验结束后统计梅花鹿体重、采食量,计算生长性能;采集血液样本,测定血清谷胱甘肽过氧化物酶、总超氧化物歧化酶(T-SOD)、碱性磷酸酶水平及丙二醛、免疫球蛋白A、免疫球蛋白G、免疫球蛋白M、甲状腺旁素、降钙素、1,25羟基维生素D_(3)、钙和磷含量。试验第75天起连续采集3 d粪便样本,测定干物质、粗蛋白质、粗脂肪、酸性洗涤纤维、中性洗涤纤维、钙及磷含量。【结果】(1)与对照组相比,饲粮添加4000 IU/kg VD_(3)显著提高了梅花鹿平均日增重(P0.05)。(2)4000 IU/kg组梅花鹿Ca表观消化率显著高于对照组(P0.05)。(3)3个试验组梅花鹿血清T-SOD水平均显著高于对照组(P0.05);饲粮添加8000 IU/kg VD_(3)显著提高了梅花鹿血清1,25羟基维生素D_(3)水平(P0.05)。【结论】饲粮添加适量VD_(3)有利于提高梅花鹿生长性能和机体抗氧化能力,增加血清1,25羟基维生素D_(3)含量。综合试验结果,4000 IU/kg VD_(3)在10~12月龄梅花鹿应用效果较好。

关键词：维生素D_(3) 梅花鹿生长性能血清生化指标

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Rainbow guiding of the lowest-order antisymmetric Lamb mode in phononic crystal plate

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Science China(Technological Sciences) 2019年第3期62卷 458-463页

作者： ZHAO JinFeng yuan weitao BONELLO Bernard DJAFARI-ROUHANI Bahram PAN YongDong ZHONG Zheng School of Aerospace Engineering and Applied Mechanics Tongji University INSP UMR CNRS 7588 Sorbonne Université UPMC Université Paris 06 Institut d'Electronique de Microélectronique et de Nanotechnologie (IEMN-UMR CNRS 8520) Université de Lille Sciences et Technologies School of Science Harbin Institute of Technology

The modern acoustic circuits have experienced significant progress with the development of artificial structures, including phononic crystals, metamaterials or metasurfaces. Among the most intensive topics, the reconfigurable acoustic guides are achieved through several mechanisms. In this work, we report on the rainbow guiding for the lowest-order antisymmetric Lamb(A_0) mode in a phononic crystal plate, where the linear waveguides are constituted by erecting aligned pillars either solid or hollow. We show both numerically and experimentally that the whispering gallery modes(WGMs) in the hollow pillars can be generated by the defect mode that propagates in the waveguide. Then, the reemission of A_0 mode by the WGMs to the outer lateral areas can lead to spatial control of frequency selective wave guidance called "rainbow guiding". Our approach allows for an accurate control of the wave guiding and facilitates the integration of waveguides within other devices in the acoustic circuits.

关键词： whispering gallery mode rainbow guiding phononic crystal

Market Operation of Energy Storage System in Smart Grid:A Review

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Energy Engineering 2024年第6期121卷 1403-1437页

作者： Li Deng Jiafei Huan Wei Wang weitao Zhang Liangbin Xie Lun Dong Jingrong Guo Zhongping Li yuan Huang Yue Xiang North China Dispatching Center North China Branch of State Grid Corporation of ChinaBeijing100053China College of Electrical Engineering Sichuan UniversityChengdu610065China

As a flexible resource,energy storage plays an increasingly significant role in stabilizing and supporting the power system,while providing auxiliary ***,the current high demand for energy storage contrasts with the fuzzy lack of market-oriented mechanisms for energy storage,the principle of market-oriented operation has not been embodied,and there is no unified and systematic analytical framework for the business ***,the dispatch management model of energy storage in actual power system operation is not ***,the specific scheduling process and energy storage strategy on the source-load-network side could be more specific,and there needs to be a greater understanding of the collaborative scheduling process of the multilevel scheduling *** this basis,this paper reviews the energy storage operation model and market-based incentive mechanism,For different functional types and installation locations of energy storage within the power system,the operational models and existing policies for energy storage participation in the market that are adapted to multiple operating states are *** the point of view of the actual scheduling and operation management of energy storage in China,an energy storage regulation and operation management model based on“national,provincial,and local”multilevel coordination is proposed,as well as key technologies in the interactive scenarios of source-load,network and storage.

关键词： Energy storage operation marketization scheduling management national-branch-provincial local dispatch

Simulation on dynamic characteristics of TC4 cutting with crack defects

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Journal of Measurement Science and Instrumentation 2024年第3期15卷 387-396页

作者： SHI Lichen WANG Jian DOU weitao yuan Jiageng School of Mechanical and Electrical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China College of Aeronautical Manufacturing Engineering Xi’an Aeronautical Polytechnic InstituteXi’an 710089China

Titanium alloys play an important role in aerospace and other ***,after precision forging and cold rolling process,some defects will appear on the subsurface of titanium alloy bars,thus reducing the surface quality and precision of turning *** study aimed at exploring the effect of crack defects on TC4 ***,the finite element cutting simulation model of TC4 material with crack defects was established in ***,the cutting parameters such as cutting force,stress concentration,chip morphology,residual stress were obtained by changing the variables such as the size and height of crack ***,the turning experiment was carried out on centerless *** results show that the cutting force changes abruptly when the defect position is located on the cutting path,the maximal stress occurs at the tip of the defect,and the mutation of stress value is more serious with the increase of defect size;the buckling deformation of chip morphology occurs and becomes less serious with the increase of the distance between the defect position and the workpiece surface;the surface residual stress near the defect is related to the stress when the tool is close to the defect,the larger defect size and the closer to the machined surface,the greater the residual ***,under certain processing conditions,the TC4 material should avoid large size defects or increase the distance between defects and the machined surface,so as to obtain better and stable surface quality.

关键词： crack defect TC4 ABAQUS centerless lathe

氮空位调控晶格畸变度强化(NbMoTaW)N_(x)薄膜的力学性质和耐磨损性

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无机材料学报 2024年第6期39卷 715-725页

作者：张睿张侃袁梦雅谷鑫磊郑伟涛吉林大学材料科学与工程学院超硬材料国家重点实验室长春130012

高熵过渡金属氮化物(HENs)具有热稳定性,抗腐蚀、抗氧化性以及优异的力学性质,可用作结构部件及运动部件的表面防护薄膜。然而,受HENs组元多样性的影响,宽泛可调的金属组分与HENs力学性质之间的映射关系相当复杂。本工作以(NbMoTaW)N_(x... 详细信息

高熵过渡金属氮化物(HENs)具有热稳定性,抗腐蚀、抗氧化性以及优异的力学性质,可用作结构部件及运动部件的表面防护薄膜。然而,受HENs组元多样性的影响,宽泛可调的金属组分与HENs力学性质之间的映射关系相当复杂。本工作以(NbMoTaW)N_(x)薄膜为研究对象,基于磁控溅射方法调节薄膜生长过程中氮气流量,制备了不同氮含量的(NbMoTaW)N_(x)(x=0,0.59,0.80,0.95)薄膜,研究了(NbMoTaW)N_(x)薄膜的成分、结构、形貌与性能,并对薄膜力学性质的主要影响机制进行了系统探究。结果表明,通过调节氮空位,实现了对氮原子及金属原子亚晶格畸变度的协同调控,得益于氮原子和金属原子亚晶格的高畸变度,(NbMoTaW)N_(0.80)样品具有最高的硬度与最好的耐磨损性能。排除电子结构、残余应力、晶粒尺寸等力学性质影响因素后,进一步确认了HENs薄膜晶格畸变度与力学性质之间的直接关系。本研究寻找到一条简洁的晶格畸变度调控策略,为调节、优化氮化物薄膜性能,进而更好地解决复杂服役环境下防护薄膜的机械损伤问题提供了新的思路。

关键词：晶格畸变度氮空位力学性质高熵过渡金属氮化物耐磨损性

乳酸菌和果寡糖对育成早期北极狐生长性能、营养物质消化率及血清生化指标的影响

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动物营养学报 2023年第4期35卷 2571-2579页

作者：张婷袁伟涛郭肖兰王凯英徐超中国农业科学院特产研究所特种动物饲养及综合利用创新工程中心吉林省特种动物微生物饲料工程研究中心长春130112

本试验旨在研究饲粮添加乳酸菌和果寡糖对育成早期北极狐生长性能、营养物质消化率及血清生化指标的影响。选取60只平均体重为(1.16±0.15)kg的分窝后雄性北极狐[(45±3)日龄],随机分成4组,每组3个重复,每个重复5只,分别饲喂以下饲粮:... 详细信息

本试验旨在研究饲粮添加乳酸菌和果寡糖对育成早期北极狐生长性能、营养物质消化率及血清生化指标的影响。选取60只平均体重为(1.16±0.15)kg的分窝后雄性北极狐[(45±3)日龄],随机分成4组,每组3个重复,每个重复5只,分别饲喂以下饲粮:基础饲粮(对照组)、基础饲粮+3×10^(9) CFU/kg乳酸菌(LAB组)、基础饲粮+5 g/kg果寡糖(FOS组)、基础饲粮+3×10^(9) CFU/kg乳酸菌+5 g/kg果寡糖(LAB+FOS组)。试验期30 d。结果显示:1)在试验第1~15天,LAB组和LAB+FOS组腹泻率较对照组和FOS组显著降低(P0.05);LAB+FOS组北极狐腹泻率显著低于对照组和FOS组(P0.05);与FOS组相比,LAB+FOS组蓝狐料重比显著下降(P0.05);各组食入氮、粪氮、尿氮、氮沉积、净蛋白质利用率和蛋白质生物学效价差异不显著(P>0.05)。3)LAB+FOS组血清总蛋白(TP)含量显著高于FOS组(P0.05);LAB组血清白蛋白(ALB)含量显著高于对照组和FOS组(P0.05);与对照组相比,LAB+FOS组血清尿素氮(UN)含量显著降低(P<0.05)。综上所述,饲粮中同时添加3×10^(9) CFU/kg乳酸菌和5 g/kg果寡糖有利于降低育成早期北极狐的腹泻率,提高干物质消化率,改善机体免疫水平,进而促进生长。

关键词：北极狐乳酸菌果寡糖生长性能营养物质消化率