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How neonatal diet affects the long-term development of rumination behavior,rumen fermentation and feed digestion in dairy calves fed a high milk level?

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Animal Nutrition 2024年第1期16卷 326-337页

作者： Jianxin Xiao Tianyu Chen Rong Peng Gibson M.Alugongo Hui Yang Shuai Liu Yulin Ma jingjun wang Shengli Li Zhijun Cao State Key Laboratory of Animal Nutrition and Feeding International Calf and Heifer OrganizationCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Key Laboratory of Low Carbon Culture and Safety Production in Cattle in Sichuan Animal Nutrition InstituteSichuan Agricultural UniversityChengdu 611130China

This study was to investigate growth performance,rumination development,rumen fermentation and feed digestion in young calves provided high volumes(about 20%of calf birth weight)of milk with or without forage inclusion and how these parameters correlate with each *** after birth,160 newborn Holstein female calves(41.6±4.2 kg of initial BW)were randomly divided into 2 treatments:1)starter(CON,only starter)and 2)starter and hay(HAY,both starter and hay).The calves were fed their respective experimental diets from d 4 to 84,after which they were all introduced to similar diets until the end of the experiment on d *** had no effect on growth and structural measurements throughout the experimental ***,treatment had an effect on the other parameters,mainly during the post-weaning *** supplementation tended to reduce starter dry matter intake(P=0.05),while increasing the forage intake(P<0.01)and the feed-to-gain ratio(P<0.01).HAY calves had increased neutral detergent fiber(NDF)and physically effective NDF(peNDF)intakes(P<0.05)and tended to lower(P<0.01)starch intake compared to CON *** HAY calves had a higher rumination time(P<0.01),ruminal pH(P<0.01),and acetate-to-propionate ratio(P=0.05)compared to the CON *** correlation analysis showed that rumination time was positively related to the ruminal p H at d 84(P=0.01)and 196(P=0.02).The HAY calves had similar apparent total-tract digestibility of dry matter(DM),NDF and ether extract(EE),but lower digestibility of organic matter(OM,P=0.03),crude protein(CP,P<0.01)and starch(P<0.01)compared to those of the CON calves at week ***,there were no positive relationships between rumination time and nutrient digestibility or between rumination time per kilogram DM and nutrient *** conclusion,feeding hay to calves fed a high milk level improved rumination during the post-weaning period only,without a concomitant effect on growth performance thro

关键词： Neonatal calf Early forage feeding Rumination Rumen fermentation Nutrient digestibility

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“意象”思维在汉字设计中的研究

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鞋类工艺与设计 2024年第16期4卷 45-47页

作者：王景君郑州轻工业大学河南郑州450000

将汉字设计与“意象”思维相结合的发展成果进行研究论述,更深入地研究如何应用意象思维特征,在汉字的构造方式和运用法则中设计汉字的字体,让汉字字体设计依然保留汉字本身的特征。

关键词：汉字设计意象思维老子美学

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节段超高性能混凝土桥梁干接缝直剪性能研究

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森林工程 2024年第1期40卷 171-182页

作者：古金伦陈双庆王靖君裴必达广东省公路建设有限公司广州510032 京珠高速公路广珠段改扩建管理处广州510032 中南大学土木工程学院长沙410075 广深珠高速公路有限公司广州东莞523000 长沙理工大学土木工程学院长沙410114

为研究节段超高性能混凝土(Ultra-High Performance Concrete,UHPC)装配式桥梁干接缝的直接剪切性能,基于有限元分析理论,在通用有限元分析软件(ABAQUS)中建模分析UHPC干接缝,得到了UHPC接缝在直剪荷载作用下的受力性能;利用已有试验数... 详细信息

为研究节段超高性能混凝土(Ultra-High Performance Concrete,UHPC)装配式桥梁干接缝的直接剪切性能,基于有限元分析理论,在通用有限元分析软件(ABAQUS)中建模分析UHPC干接缝,得到了UHPC接缝在直剪荷载作用下的受力性能;利用已有试验数据对美国国家公路(American Association of State Highway and Transportation Officials,AASHTO)节段桥梁设计规范及多位学者所提出的UHPC干接缝抗剪承载力计算公式进行适用性及准确性评价;同时结合收集的实测数据拟合得到UHPC干接缝直剪承载力公式。结果表明,基于混凝土塑性损伤理论的ABAQUS计算模型可以较好模拟UHPC干接缝的直剪受力特征,各个模型试验结果与有限元结果的比值的平均值为0.970,变异系数为0.107;基于普通混凝土结构的美国AASHTO公式和西班牙ATEP公式不能准确预测UHPC干接缝的抗剪承载力,计算结果偏于不安全;前期学者提出的UHPC接缝计算公式预测结果偏保守,经济性较差;该研究给出的计算公式预测准确,可为实际节段UHPC装配式桥梁的接缝设计与计算提供参考。

关键词：桥梁工程 UHPC 干接缝有限元分析直剪承载力

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Pb induced dislocation defects of PtCo systems: Strain-triggered oxygen reduction reaction for PEMFC

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Nano Research 2024年第4期17卷 2462-2472页

作者： Chun Jin Qiheng wang jingjun Liu Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China Beijing University of Chemical Technology Beijing 100029China

Design and development of advanced electrocatalysts with high performance and low Pt consumption are crucial for reducing the kinetic energy barrier of the cathode oxygen reduction reaction(ORR)and improving the efficiency of proton exchange membrane fuel cells(PEMFC).In this study,we demonstrate a Pb-modulated PtCo system for efficient ORR,in which the inclusion of Pb in ternary alloys induces dislocation defects due to the significant difference in atomic ***-PtCoPb was confirmed to exhibit significantly higher ORR activity and stability in acidic *** practical PEMFC applications,it outperforms the corresponding commercial Pt/C with a mass activity of 0.58 A·mgPt^(-1),making it a promising alternative to state-of-the-art Pt-based *** combination of experimental results and density functional theory(DFT)calculations offers valuable atomic-level insights into the dislocation *** with a larger atomic radius is located in the lattice stretching region below the dislocation slip plane,forming a structure similar to a Cottrell atmosphere,which reduces the dislocation energy and puts the system in a lower energy *** Cottrell atmosphere pins the dislocation structure and stabilizes the ternary *** adjusting the amount of added Pb,a moderate level of dislocation density induces a tuned strain effect,thereby enhancing the electrocatalytic mechanism by optimizing the electronic structure of the alloy surface and the adsorption and desorption of oxygen *** work provides valuable insights into the design and development of lattice dislocation defect structures to trigger strain effects for improving ORR performance.

关键词： dislocation defect strain effect Pb-modulated oxygen reduction reaction

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出口智利的内燃电力双动力动车组研制

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铁道机车与动车 2024年第2期 7-10页

作者：王京军高洪镇李艳飞中车青岛四方机车车辆股份有限公司山东青岛266111

介绍了中车青岛四方股份公司出口智利的内燃电力双动力动车组的总体布置、技术参数以及主要技术特点等。

关键词：内燃电力双动力动车组

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Small amount but big impact:Trace oxygen interstitially inserted PtCu alloys by microalloying for efficient oxygen reduction catalysis

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Nano Research 2024年第8期17卷 7001-7012页

作者： Qiheng wang Zhiguo Chen Jingyan Zhang jingjun Liu Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China Beijing University of Chemical Technology Beijing 100029China

The introduction of small size non-metal elements(e.g.,oxygen)into solid solution alloys may be a promising strategy for fabricating efficient Pt-based catalysts with high activity and stability toward oxygen reduction reaction(ORR).Herein,oxygen interstitially inserted PtCu(O-PtCu)alloys are firstly designed by an oxygen-microalloying strategy,through ultraviolet(UV)irradiation-assisted galvanic replacement in an aqueous solution containing H_(2)PtCl_(6) and Cu_(2)O nanowires as sacrificial *** obtained O-PtCu alloys feature a typical face-centered cubic(FCC)structure with majority Pt,Cu atoms as building bricks and trace interstitial oxygen(1.65 wt.%)existed in the octahedral sites surrounding Cu atoms,leading to a short-range disordered *** alloy reaches a recorded half-wave potential of 0.96 V(*** hydrogen electrode(RHE))and mass activity of 0.48 A·mgPt^(−1),much higher than those of commercial Pt/*** the accelerated degradation test(ADT),the mass activity lost only 4.2%after 10k cycles,while the commercial Pt/C lost 66.7%under the same *** with pure Pt and undoped PtCu alloy,the remarkably improved performance can be attributed to the lattice distortion and energy band reconstruction caused by the interstitial oxygen atoms in form of Cu–O ***,the stable Cu–O bonds delay the possible place exchange between surface Pt atoms and surface-adsorbed oxygen species,thereby hindering Pt dissolution,providing a new paradigm to address Pt degradation ***,the introduction of interstitial oxygen into Pt-based alloys may be a facile and smart strategy for the development of advanced Pt-based alloys electrocatalysts.

关键词： oxygen-microalloying platinum alloys octahedral interstices oxygen reduction reaction

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The age at first consumption of forage in calves and its effect on growth and rumination in the short‑and long‑term

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畜牧与生物技术杂志:英文版 2023年第5期14卷 2143-2157页

作者： Jianxin Xiao Tianyu Chen Rong Peng Gibson Maswayi Alugongo Hui Yang Muhammad Zahoor Khan Shuai Liu Yulin Ma jingjun wang Wei wang Yajing wang Shengli Li Zhijun Cao Key Laboratory of Low Carbon Culture and Safety Production in Cattle in Sichuan Animal Nutrition InstituteSichuan Agricultural UniversityChengdu 611130People’s Republic of China State Key Laboratory of Animal Nutrition International Calf and Heifer OrganizationCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193People’s Republic of China

Background Previous investigations into the effect of dietary forage on calf performance have been inconsistent,and there is a paucity of information exploring the effect of age on the growth performance and rumination of ***-four female Holstein calves(41.5±4.2 kg)were enrolled at birth,a subset of the calves were fed calf starter only(CON,n=21)while the rest(n=63)were classified into three treatment groups:the early(EHAY,n=26,5.1±0.8 d),the middle(MHAY,n=21,7.9±0.8 d)and the late(LHAY,n=16,12.1±1.4 d)hay *** short-term effect of the age at first forage consump-tion(AFF)on calves’feed intake was monitored until d *** addition,the long-term effects of AFF on body weight,structural growth and rumination behavior were recorded until d *** samples were collected on d 1,7,35,84 and 196 to ana-lyze the rumen fermentation,while fecal samples were collected from d 78 to 84 to estimate digestibility *** Treatment had no effect on feed ***,the EHAY calves tended to have lower BW and ADG compared to LHAY and CON *** total-tract apparent digestibility parameters and digestible nutrients intake were significantly lower in EHAY calves compared with CON and LHAY *** in the EHAY group tended to begin ruminating ealier,while CON calves were the latest(12.3 vs.15.5 days of age).A treatment and time interaction was present for rumination time due to greater rumination in calves consuming hay compared to CON calves in week 10 to 12,the differences in rumination disappeared afterwards,no long-lasting significant differences in the rumina-tion and rumen fermentation parameters were found between *** In conclusion,this study showed that hay consumption earlier in life(in the first week,around 5 days of life)could negatively affect the growth of the calf in the short and long *** to consuming hay from the second week(around 12 days of life)or feeding concentrate only without hay,starting

关键词： Age at first forage consumption Dairy calf Growth Nutrient digestibility Rumen fermentation Rumination

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A DIRECT DISCONTINUOUS GALERKIN METHOD FOR TIME FRACTIONAL DIFFUSION EQUATIONS WITH FRACTIONAL DYNAMIC BOUNDARY CONDITIONS

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Journal of Computational Mathematics 2024年第1期42卷 156-177页

作者： jingjun Zhao Wenjiao Zhao Yang Xu School of Mathematics Harbin Institute of TechnologyHarbin 150001China

This paper deals with the numerical approximation for the time fractional diffusion problem with fractional dynamic boundary *** well-posedness for the weak solutions is studied.A direct discontinuous Galerkin approach is used in spatial direction under the uniform meshes,together with a second-order Alikhanov scheme is utilized in temporal direction on the graded mesh,and then the fully discrete scheme is ***,the stability and the error estimate for the full scheme are analyzed in *** experiments are also given to illustrate the effectiveness of the proposed method.

关键词： Time fractional diffusion equation Numerical stability Convergence

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台州地区厚皮甜瓜品种比较与筛选试验

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浙江农业科学 2024年第5期65卷 1092-1096页

作者：岳雅妮漆慧娟王颖徐竞成刘曙东王靖君陈伟强台州市农业科学研究院浙江台州318000

为筛选出适合台州地区设施栽培的高产优质厚皮甜瓜品种,给广大农户选种提供科学依据,试验以东方蜜1号为对照,对引进的9个厚皮甜瓜品种进行田间试验,考察生育期、品质、产量等性状。试验结果表明,脆肉型甜瓜丰登蜜25、浙甜401,软肉型甜... 详细信息

为筛选出适合台州地区设施栽培的高产优质厚皮甜瓜品种,给广大农户选种提供科学依据,试验以东方蜜1号为对照,对引进的9个厚皮甜瓜品种进行田间试验,考察生育期、品质、产量等性状。试验结果表明,脆肉型甜瓜丰登蜜25、浙甜401,软肉型甜瓜雅绿醇香这3个品种综合表现较好,适宜在台州地区推广栽培。丰登蜜25为浅绿色椭圆形网纹甜瓜,味道甘甜、爽脆可口,中心糖度17.5%,667 m^(2)产量1623.7 kg。浙甜401为白色光皮甜瓜,味道清甜、松脆多汁,中心糖度16.4%,667 m^(2)产量1548.3 kg。雅绿醇香为浅绿色圆形光皮甜瓜,甘甜多汁,细腻绵软,中心糖度17.8%,667 m^(2)产量1489.9 kg。此外,翠雪7号生育期短,浙甜105品质优异,这2个品种单项优势明显,可适当种植满足不同市场需求。

关键词：厚皮甜瓜品种比较台州地区

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Oxidation Resistance of In Situ Reaction/Hot Pressing Synthesized Ti_(2)AlC-20%TiB_(2) Composite at 600-900℃in Air

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 739-748页

作者： Wenting wang jingjun Xu Jun Zuo Ke Ma Yang Li Guangqi He Meishuan Li Shengyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

The oxidation behavior and kinetics of Ti_(2)AlC-20vol.%TiB_(2) composite at 600-900℃ in air were *** results showed that the oxidation kinetics of the composite followed a logarithmic law within the given temperature range,which indicated that the composites had excellent oxidation *** selective oxidation of Al in Ti_(2)AlC was greatly enhanced,which facilitated the formation of a continuous and dense protective layer of Al_(2)O_(3).Meanwhile,the existence of molten B_(2)O_(3) inhibited the outward diffusion of Ti and inward diffusion of oxygen,which prevented the growth of anatase TiO_(2) at 600℃ and rutile TiO_(2) at 700-900℃.Therefore,the incorporation of TiB_(2) completely inhibited the abnormally rapid oxidation of bulk Ti_(2)AlC at 600℃ and improved its oxidation resistance at 700-900℃.

关键词： MAX phase Ti_(2)AlC-TiB_(2)composite Intermediate temperature oxidation Oxidation kinetics

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