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天府肉鸡配套系纯系选育进展

四川农业大学学报 2024年第3期42卷 645-651页

作者：彭蕾蕾孙鑫田尧夫刘哲良翟晨灿杨建华赵小玲四川农业大学动物科技学院/猪禽种业全国重点实验室成都611130 四海三联农业开发有限公司四川广元628021

【目的】对天府肉鸡3个品系的选育情况进行分析,以优化天府肉鸡的选育。【方法】对天府肉鸡13个世代的体重增长、料重比、体尺性状以及屠宰性状数据进行比较分析。【结果】第13世代TF03系的70日龄体重增长显著高于TF01系和TF02系(P<0.01... 详细信息

【目的】对天府肉鸡3个品系的选育情况进行分析,以优化天府肉鸡的选育。【方法】对天府肉鸡13个世代的体重增长、料重比、体尺性状以及屠宰性状数据进行比较分析。【结果】第13世代TF03系的70日龄体重增长显著高于TF01系和TF02系(P<0.01);65日龄公鸡的龙骨长、胸围和胸宽等体尺性状以及屠体重、半净膛重和瘦肉重等屠宰性状也显著大于TF01系和TF02系(P<0.05)。与第6世代相比,第13世代3个品系的70日龄重极显著增高(P<0.01),且变异系数在10%以内。【结论】持续13个世代的选育对天府肉鸡配套系3个纯系的性状选择效果明显。

关键词：天府肉鸡品系选育生长性能

SCALE EFFECT OF I MPINGING PRESSURE CAUSED BY SUBMERGED JET

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Journal of Hydrodynamics 2005年第4期17卷 478-482页

作者： tian Zhong XU wei-lin WANG wei LIU Shan-jun DONG Jian-wei State Key Hydraulics Laboratory of High Speed Flows Sichuan University Chengdu 610065 China Military Oil Supply Engineering Department Logistical Engineering University Chongqing 400016China

The characteristics of the impinging pressure at the jet equipment where the maximum jet velocity can reach 50m/s were studied. By comparing the impinging pressure with the one measured at the low velocity conditions, two conclusions of the scale effect are drawn： firstly, the velocity attenuation degree is smaller than that of low velocity jet, and secondly, the relative impinging width is narrower than that of low-velocity jet. The reasons of the scale effect of the impinging pressure were elucidated through numerical simulation.

关键词： scale effect impinging pressure high-velocity jet numerical simulation

Evaluation, prediction, and protection of water quality in Danjiangkou Reservoir, China

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Water Science and Engineering 2015年第1期8卷 30-39页

作者： Xiao-kang xin Ke-feng Li Brian Finlayson wei Yin State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Changjiang Water Resources Protection Institute Changjiang Water Resources Commission Department of Resource Management and Geography the University of Melbourne

The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project （SNWDP）, which commenced transferring water in 2014. Integrated research on the evaluation, prediction, and protection of water quality in the Danjiangkou Reservoir was carried out in this study in order to improve environmental management. Based on 120 water samples, wherein 17 water quality indices were measured at 20 monitoring sites, a single factor evaluation method was used to evaluate the current status of water quality. The results show that the main indices influencing the water quality in the Danjiangkou Reservoir are total phosphorus （TP）, permanganate index （CODM,）, dissolved oxygen （DO）, and five-day biochemical oxygen demand （BODs）, and the concentrations of TP, BODs, ammonia nitrogen （NH3--N）, CODM,, DO, and anionic surfactant （Surfa） do not reach the specified standard levels in the tributaries. Seasonal Mann--Kendall tests indicated that the CODMn concentration shows a highly significant increasing trend, and the TP concentration shows a significant increasing trend in the Danjiangkou Reservoir. The distribution of the main water quality indices in the Danjiangkou Reservoir was predicted using a two-dimensional water quality numerical model, and showed that the sphere of influence from the tributaries can spread across half of the Han Reservoir if the pollutants are not controlled. Cluster analysis （CA） results suggest that the Shending River is heavily polluted, that the Jianghe, Sihe, and Jianhe rivers are moderately polluted, and that they should be the focus of environmental remediation.

关键词： Water quality Single factor evaluation method Mann--Kendall test Numerical modeling Cluster analysis Dangjiangkou Reservoir

Numerical Approach for Atmospheric Corrosion Monitoring Based on EIS of a Weathering Steel

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Acta Metallurgica Sinica(English Letters) 2015年第2期28卷 261-271页

作者： Ch.Thee Long Hao Jun-Hua Dong xin Mu wei Ke State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences

Electrochemical impedance spectroscopy （EIS） and film thickness measurement have been employed to study the atmospheric corrosion of a weathering steel covered with a thin electrolyte layer in a simulated coastal-industrial atmosphere. The results indicate that the corrosion rate is a function of the covered electrolyte thickness and the wet/dry cycle. Within each wet/dry cycle, the increased corrosion rate is related to the increased Cl^- and SO4^2- concentration and an enhancement of oxygen diffusion rate with the evaporation of the electrolyte. In addition, the corrosion rate increases during the initial corrosion stage and then decreases as the wet/dry cycle proceeds. Moreover, one mathematical approach based on the numerical integration method to obtain corrosion mass loss of steel from the measurements of EIS has been developed, and this would be useful for the development of indoor simulated atmospheric corrosion tests.

关键词： Weathering steel Atmospheric corrosion Electrochemical impedance spectroscopy Steel rust Coastal-industrial atmosphere

对抗环境中基于种群多样性的鲁棒策略生成方法

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计算机工程与科学 2024年第6期46卷 1081-1091页

作者：庄述鑫陈永红郝一行吴巍炜徐学永王万元东南大学计算机科学与工程学院江苏南京211189 沈阳飞机设计研究所扬州协同创新研究院有限公司江苏扬州210016 北方信息控制研究院集团有限公司江苏南京211189

在对抗博弈环境中,目标智能体希望生成具有高鲁棒性的博弈策略,使得目标智能体在面对不同对手策略时,始终具有较高的收益。现有的基于自我博弈的策略生成方法通常会过拟合到针对对手某个特定策略进行学习,所学习到的策略鲁棒性低且容易... 详细信息

在对抗博弈环境中,目标智能体希望生成具有高鲁棒性的博弈策略,使得目标智能体在面对不同对手策略时,始终具有较高的收益。现有的基于自我博弈的策略生成方法通常会过拟合到针对对手某个特定策略进行学习,所学习到的策略鲁棒性低且容易受到其他对手策略的攻击。此外,现有的结合深度强化学习和博弈论方法迭代生成对手策略的方法在复杂且具有庞大决策空间的对抗场景下收敛效率低。鉴于此,提出一种基于种群多样性的鲁棒策略生成方法,其中对抗双方各自维护一个种群策略池,并且需要保证种群中的策略是具有多样性的,以此生成鲁棒的目标策略。为了保证种群多样性,将从策略的行为和质量2个视角度量策略的多样性,其中行为多样性是指不同策略状态-动作轨迹的差异性,质量多样性是指不同策略面对相同对手时最终获得的收益的差异性。最后,在典型的具有连续状态、连续动作的对抗环境中验证了所提出的基于种群多样性所生成的策略的鲁棒性。

关键词：对抗环境深度强化学习种群多样性 Shapley value 行为表征

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外阴硬化性苔藓病变中的抗氧化酶变化

临床与病理杂志 2024年第1期44卷 1-7页

作者：徐倩倩王威石洪爽武昕中国医科大学附属第一医院妇科沈阳110001

目的:外阴硬化性苔藓(vulvar lichen sclerosus,VLS)是一种外阴皮肤瘙痒、变白的自身免疫性慢性炎症性疾病。目前VLS的发病机制尚不清楚,有研究表明其可能与氧化应激有关。本研究旨在通过探讨锰超氧化物歧化酶(Mn superoxide dismutase,... 详细信息

目的:外阴硬化性苔藓(vulvar lichen sclerosus,VLS)是一种外阴皮肤瘙痒、变白的自身免疫性慢性炎症性疾病。目前VLS的发病机制尚不清楚,有研究表明其可能与氧化应激有关。本研究旨在通过探讨锰超氧化物歧化酶(Mn superoxide dismutase,MnSOD)、细胞质内过氧化物酶2(peroxidase 2,PRDX2)、硫氧还蛋白1(thioredoxin 1,TRX1)3种抗氧化酶在VLS中的表达情况及其与VLS发生和发展的关系。方法:选取中国医科大学附属第一医院妇科门诊手术切除的VLS组织标本40例(其中早期20例,进展期20例),外阴整形术切除的正常外阴皮肤组织标本20例。采用免疫组织化学SP方法检测MnSOD、PRDX2和TRX1蛋白在外阴皮肤组织中的表达情况,并在高倍显微镜下测定平均光密度值。采用Pearson相关分析计算VLS组织中MnSOD、PRDX2、TRX1三者之间的相关性。结果:VLS组织中MnSOD的平均光密度值低于正常外阴皮肤组织(P<0.05),早期VLS组织中MnSOD平均光密度值高于进展期VLS组织(P<0.05);VLS组织中PRDX2的平均光密度值高于正常外阴皮肤组织(P<0.05),早期VLS组织中PRDX2的平均光密度值低于进展期VLS组织(P<0.05);VLS组织中TRX1的平均光密度值高于正常外阴皮肤组织(P<0.05),早期VLS组织中TRX1平均光密度值低于进展期VLS组织(P<0.05)。Pearson相关分析结果显示:MnSOD和PRDX2(r=-0.615)、MnSOD和TRX1(r=-0.881)的表达均呈负相关(均P<0.05);PRDX2和TRX1表达呈正相关(r=0.670,P<0.05)。结论:在VLS病变进展中,抗氧化酶MnSOD表达减少,PRDX2和TRX1表达增加。

关键词：外阴硬化性苔藓超氧化物歧化酶过氧化物酶2 硫氧还蛋白1

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The whole-genome survey of Acer griseum,its polymorphic simple sequence repeats development and application

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BIOCELL 2023年第8期47卷 1907-1913页

作者： XIAO-JUN ZHOU YU-wei tian RUI-HAN LI Life Science College Luoyang Normal UniversityLuoyang471934China The Second Institute of Resources and Environment Investigation of Henan Province Luoyang471000China

Background:Acer griseum Pax is an endangered species endemic to China with both ornamental and economic ***,the lack of information on its genome size and characteristics hinders further work at the genome ***:This paper applied bioinformatics methods to predict the characteristics and patterns of the *** genome,providing an important basis for formulating its whole-genome sequencing *** study also characterized the simple sequence repeats(SSRs)of ***,laying the foundation for the development and application of genome-wide SSR *** this study,PE150 sequencing was performed by the BGI MGISEQ platform,and the sequence files were analyzed by the K-mer method to estimate the characteristic information by GCE ***:The genome size was finally determined to be 739.63 Mb,its heterozygosity ratio was 1.33%,and the repetition ratio was 65.68%.A total of 825,960 SSR loci were identified in the assembled genome sequence,and primers were successfully designed for 526,020 *** verify the effectiveness of these primers,100 pairs of primers were randomly selected and synthesized,and 81 pairs successfully amplified the target *** pairs of primers with good polymorphism were selected for principal component analysis of 31 *** individuals from two populations,showing favorable heterozygosity and PIC *** to the findings,these SSRs might identify genetic variations based on geographic ***:It is suggested that Illumina+PacBio assembly strategy should be used for whole-genome sequencing due to the high heterozygosity rate and high repetition rate of the *** addition,the SSR primers designed in batches in this study laid a foundation for the in-depth study of population structure and population maintenance mechanism of ***,which is helpful for the effective conservation and sustainable utilization of this germplasm resource.

关键词： Endangered plant Paperbark maple Genome Genetic conservation

STUDY OF VORTEX CHARACTERISTICS OF THE FLOW AROUND A HORIZONTAL CIRCULAR CYLINDER AT VARIOUS GAP-RATIOS IN THE CROSS-FLOW

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Journal of Hydrodynamics 2006年第3期18卷 334-340页

作者： QI E-rong LI Guo-ya LI wei WU Jian ZHANG xin State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan430072 China China Three Gorges Project Corporation Yichang 443002 China Central South Building Design Institute Wuhan 430071 China

In the gap-ratio range of 0.0≤G≤7.0, a particle image velocimetry PIV is applied to conduct a systematic experimental research of the flow around a horizontal circular cylinder in the cross-flow of shallow water. The velocity distribution of transient flow field at various gap-ratios is obtained. Based on these data, the phenomena and rules of the vortex and its course of generation, development and evolvement at various gap-ratios are analyzed, and it is found that there are similar unshedding vortex structures at G = 0.0 and G = 7.0, and others are structures of shedding vortex. The figures of typical vortex movements are given. Based on this, the differences between the transient flow field and the time-averaged flow field and the characteristics of the vortex structures are analyzed. In addition when the Strouhal number keeps constant （about 0.2） concerning vortex shedding have been discussed. The findings of this paper are of guiding significance for engineering issues with similar flowing features.

关键词： PIV flow around a circular cylinder vortex structure Strouhal number

Influence of carbon content on microstructure and mechanical properties of 1000 MPa deposited metal by gas metal arc welding

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Journal of Iron and Steel Research International 2019年第5期26卷 512-518页

作者： Tong-bang An Jin-shan wei Lin Zhao Ji-guo Shan Zhi-ling tian Central Iron & Steel Research Institute Beijing 100081 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

The effects of carbon content (0.078-0.100 wt.%) on the microstructure and properties of 1000 MPa grade deposited metal produced by gas metal arc welding have been investigated. Experimental results show that the microstructure of the deposited metal was mainly composed of martensite, bainite and retained austenite. With increasing carbon content, the proportion of martensite increased, and the amount of bainite was reduced. High carbon content is beneficial to strength, but harmful to impact toughness, and thus, carbon reductions lead to the increase in impact toughness. When the carbon content was 0.100 wt.%, the lowest Charpy absorbed energy of 47 J at — 40℃ for the deposited metal was achieved, the highest yield strength of 1038 MPa was attained, and the yield-to-tensile ratio was more than 0.88, while the highest Charpy absorbed energy of 55.7 J at — 40℃ and the lowest yield strength of 915 MPa were obtained when the deposited metal contains 0.078 wt.% C, and the yield-to-tensile ratio was less than 0.85. It is concluded that bainite fraction and fine effective grain size were the dominant factors to achieve good comprehensive mechanical properties (the required strength and an acceptable toughness) of deposited metals with various carbon contents.

关键词： 1000 MPa grade deposited metal Carbon content Microstructure Strength Gas metal arc welding Impact toughness