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Frontiers of Environmental Science & Engineering 2017年第3期11卷 131-140页

作者： xiaoyan song Rui Liu Lujun Chen Baogang Dong Tomoki Kawagishi Zhejiang Provincial Key Laboratory of Water Science and Technology Department of Environment in Yangtze Delta Region Institute of Tsinghua University-Zhejiang Jiaxing 314006 China School of Environment Tsinghua University Beijing 100084 China Aqua Development Center Mitsubishi Rayon Co. Ltd. Toyohashi 4408601 Japan

An intermittently aerated sequencing batch reactor （IASBR） and a traditional sequencing batch reactor （SBR） were parallelly constructed to treat digested piggery wastewater, which was in high NH4＋ -N concentration but in a low COD/TN ratio. Their pollutant removal perfonnance was compared under COD/TN ratios of 1.6-3.4 d and hydraulic retention times of 5 3 d. The results showed that the IASBR removed TN, NH4＋-N and TOC more efficiently than the SBR. The average removal rates of TN, NH4＋-N and TOC were 83.1%, 96.5%, and 89.0%, respectively, in the IASBR, significantly higher than the corresponding values of 74.8%, 82.0%, and 86.2%. in the SBR. Mass balance of organic carbon revealed that the higher TN removal in the IASBR might be attributed to its efficient utilization of the organic carbon for denitrification, since that 48.7%- 52.2% of COD was used for denitrification in the IASBR, higher than the corresponding proportion of 43.1%-47.4% in the SBR. A prc-anoxic process in the IASBR would enhance the ammonium oxidation while restrict the nitrite oxidation. Anoxic duration of 40-80 min should be beneficial for achieving stable nitritation.

关键词： Anoxic stress Carbon source Digested piggery wastewater Intermittently aerated SBR （IASBR）Total nitrogen

A new Monte Carlo simulation of three-dimensional microstructures and their evolution in polycrystalline

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Chinese Science Bulletin 1999年第15期44卷 1432-1436页

作者： xiaoyan song Guoquan Liu Nanju Gu Hebei Univ Technol Sch Mat Sci & Engn Tianjin 300130 Peoples R China Beijing Univ Sci & Technol Sch Mat Sci & Engn Beijing 100083 Peoples R China

A new Monte Carlo simulation method for studying three-dimensional microstructures as well as their evolution in polycrystalline materials has been set up. The algorithm is simple and flexible to apply. With the present method, kinetics of three-dimensional grain growth is accurately reflected and the simulation efficiency is greatly improved. The simulation can not only be used reliably to analyze quantitatively the microstructures and their evolution, but also be used conveniently to observe microstructures as well as their evolution on the horizontal section and the sections at any angle to the horizontal plane, to measure the characteristic parameters in three dimensions and cross-sections, together with their relationships between the two systems, and to many other aspects.

关键词： three-dimensional microstructures of materials normal grain growth kinetics of microstructures evolution Monte Carlo simulation.

TI-RADS 4类甲状腺结节患者的超声弹性应变率比值与结节性质的关联

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中国耳鼻咽喉头颈外科 2024年第3期31卷 141-146,151页

作者：柯和平宋晓艳武汉科技大学附属汉阳医院超声科湖北武汉430051

目的探讨甲状腺影像报告和数据系统(TI-RADS)4类甲状腺结节患者的超声弹性应变率比值(strain ratio,SR)与结节性质的关联。方法选择2018年1月~2023年2月于武汉科技大学附属汉阳医院接受治疗的95例甲状腺结节患者(结节数共128枚)为研究对... 详细信息

目的探讨甲状腺影像报告和数据系统(TI-RADS)4类甲状腺结节患者的超声弹性应变率比值(strain ratio,SR)与结节性质的关联。方法选择2018年1月~2023年2月于武汉科技大学附属汉阳医院接受治疗的95例甲状腺结节患者(结节数共128枚)为研究对象,根据病理学检查结果分为良性组(n=50)和恶性组(n=45),比较两组患者的一般资料。利用最小绝对收缩选择算子(least absolute shrinkage and selection operator,LASSO)回归法和多因素Logistic回归分析影响患者结节性质的危险因素。按SR从低到高等分为五分位数组(Q1~Q5),比较5组患者的临床资料特征,并采用多因素Logistic回归分析SR与恶性结节风险的相关性,建立限制性立方样条Logistic回归模型分析其剂量-反应关系。采用限制性三次样条回归法分析SR与甲状腺恶性结节中央区淋巴结转移风险的非线性关联。建立回归方程y=1-1/(1+e-z)预测模型并进行验证。结果良性组与恶性组患者在舒张末期血流速度(end diastolic velocity,EDV)、促甲状腺激素(TSH)、收缩期峰值血流速度(peak systolic velocity,PSV)、阻力指数(resistance index,RI)、SR之间的差异均有统计学意义(P<0.05);LASSO回归和多因素Logistic回归分析显示调整潜在混杂因素后,发现TSH、PSV、RI增大、EDV及SR降低均为影响患者结节性质的独立危险因素(P<0.05);SR与恶性结节风险存在独立相关性(OR=0.60,95%CI 0.41~0.81,P<0.001),且SR从低到高五分位数组趋势性检验差异有统计学意义(P趋势<0.001);限制性立方样条模型分析显示,男性或女性的SR与恶性结节风险均不存在非线性关系。限制性三次样条回归分析显示,SR和甲状腺恶性结节中央区淋巴结转移风险存在显著相关性。SR=-2.1时,线性P<0.0001。经Bootstrap自抽样,预测模型区分度、准确度较好。结论TI-RADS4类甲状腺结节患者的SR和结节性质具有独立相关性,SR能够通过病灶组织的硬度判断结节性质,对患者结节性质具有较好的预测价值。

关键词：甲状腺结节危险因素甲状腺影像报告和数据系统超声弹性应变率

Short-term effects of nitrogen deposition on soil respiration components in two alpine coniferous forests, southeastern Tibetan Plateau

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Journal of Forestry Research 2019年第3期30卷 1029-1041页

作者： Jian Wang Genxu Wang Yu Fu Xiaopeng Chen xiaoyan song Land and Resource College China West Normal University Nanchong 637002SichuanPeople’s Republic of China Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences#9Block 4 Renminnanlu RoadWuhou DistrictChengdu 610041 People’s Republic of China Department of Politics and Administration China West Normal UniversityNanchong 637002SichuanPeople’s Republic of China Graduate University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Nitrogen (N) deposition to alpine forest ecosystems is increasing gradually, yet previous studies have seldom reported the effects of N inputs on soil CO2 flux in these ecosystems. Evaluating the effects of soil respiration on N addition is of great significance for understanding soil carbon (C) budgets along N gradients in forest ecosystems. In this study, four levels of N (0, 50, 100, 150 kg N ha^-1 a^-1) were added to soil in a Picea baifouriana and an Abies georgei natural forest on the Tibetan Plateau to investigate the effect of the N inputs on soil respiration. N addition stimulated total soil respiration (Rt) and its components including heterotrophic respiration (Rh) and autotrophic respiration (Ra);however, the promoted effects declined with an increase in N application in two coniferous forests. Soil respiration rate was a little greater in the spruce forest (1.05 μmol CO2 m^-2 s^-1) than that in the fir forest (0.97 μmol CO2 m^-2 s^-1). A repeated measures ANOVA indicated that N fertilization had significant effects on Rt and its components in the spruce forest and Rt in the fir forest, but had no obvious effect on Rh or Ra in the fir forest. Rt and its components had significant exponential relationships with soil temperature in both forests. N addition also increased temperature sensitivity (Q10) of Rt and its components in the two coniferous forests, but the promotion declined as N in put increased. Important, soil moisture had great effects on Rt and its components in the spruce forest (P0.05). Following N fertilization, Ra was significantly and positively related to fine root biomass, while Rh was related to soil enzymatic activities in both forests. The mechanisms underlying the effect of simulated N deposition on soil respiration and its components in this study may help in forecasting C cycling in alpine forests under future levels of reactive N deposition.

关键词： N addition Heterotrophic soil respiration Autotrophic soil respiration Q10 Alpine forest ecosystem

水分含量对轻腌大黄鱼贮藏期间细菌菌相和风味特征的影响

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食品科学 2024年第8期45卷 210-217页

作者：张曦鹏蒋中权郭全友宋晓燕无宁德师范学院生命科学学院福建宁德352100 中国水产科学研究院东海水产研究所上海200090 上海理工大学健康科学与工程学院上海200093

研究水分含量对轻腌大黄鱼在4℃条件下贮藏性的影响,分析整个贮藏期间总挥发性盐基氮含量变化、微生物群落组成、滋味和挥发性风味物质(volatile organic compounds,VOCs)差异,并对微生物组成和VOCs进行相关性分析。结果表明,3种水分质... 详细信息

研究水分含量对轻腌大黄鱼在4℃条件下贮藏性的影响,分析整个贮藏期间总挥发性盐基氮含量变化、微生物群落组成、滋味和挥发性风味物质(volatile organic compounds,VOCs)差异,并对微生物组成和VOCs进行相关性分析。结果表明,3种水分质量分数(60%、55%、50%)轻腌大黄鱼货架期依次为27、33、39 d;贮藏期间菌相发生明显的变化,货架期终点4株优势腐败菌占比较高,其中水分质量分数60%样品中蜂房哈弗尼菌(Hafnia alvei)(61.22%)和热杀索丝菌(Brochothrix thermosphacta)(19.39%)占比最高,55%水分质量分数样品中蜂房哈弗尼菌、热杀索丝菌、广布肉毒杆菌(Carnobacterium divergens)和弗氏柠檬酸杆菌(Citrobacter freundii)均占据较高比重,分别为31.13%、29.25%、17.92%、16.98%,50%水分质量分数轻腌大黄鱼货架期终点并未出现弗氏柠檬酸杆菌,但蜂房哈弗尼菌和热杀索丝菌分别高达43.96%和37.36%;电子舌结果分析发现3组样品滋味响应值变化趋势基本一致;气相色谱-离子迁移谱仪共检测出29种VOCs,主要包括醇类7种,酯类6种,酮类4种,醛类4种,胺类3种,杂环类2种,烯烃类、醚类和萜类各1种,指纹图谱结果分析发现各组样品在贮藏期间的VOCs组成上无显著差异;Pearson相关分析表明,3组样品贮藏期间蜂房哈弗尼菌和热杀索丝菌与一些胺类物质呈正相关。

关键词：轻腌大黄鱼水分含量货架期菌相挥发性风味物质

Three-Dimensional and Cross-sectional Characteristics of Normal Grain Growth Based on Monte Carlo Simulation

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 129-133,139页

作者： xiaoyan song Guoquan Liu(Material Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China)(Department of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China) Material Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Departments of Materials Science and Engineering Hebei University of Technology Tianjin 300130 China

An appropriate Monte Carlo method was developed to simulate the three-dimensional normal grain growth more completely. Comparative investigation on the three-dimensional and the cross-sectional characteristics of normal grain growth was done. It was found that the time exponent of grain growth determined from cross-section exhibits the same rule of increasing slowly with time and approaching the theoretical value n = 0.5 of steadygrain growth as the three-dimensional (3-D) system. From change of the number of grains per unit area with timemeasured in cross-section, the state of 3-D normal grain growth may be predicted. The gtain size distribution incross-section is different from that in 3-D system and can not express the evolution characteristic of the 3-D distribution. Furthermore, there exists statistical connection between the topological parameters in cross-section and thosein three-dimensions.

关键词： Monte Carlo simulation normal grain growth three-dimension cross-section characteristics

Anode material with Li-Si nano-domains in three-dimensional carbon network

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Progress in Natural Science:Materials International 2019年第6期29卷 310-315页

作者： Chao Hou Ke Yang Fawei Tang Haibin Wang Xuemei Liu xiaoyan song College of Materials Science and Engineering Key Laboratory of Advanced Functional Materials Education Ministry of China Beijing University of Technology

A micro-nano combined composite with Li-Si alloy nano-domains in three-dimensional carbon network was prepared as a novel electrode material.The carbon network constrained the volume contraction and promoted effectively charge transfer of the whole active material.Meanwhile,the abundant interfaces between Li-Si alloy and carbon bound by Li-C ionic bonds,not only enhanced the delithiation at interface but also ensured the structural integrity.The present composite exhibited excellent electrochemical performance.The specific capacity at the first lithiation was as high as 1133 mAh g-1at a current density of 0.1 A g-1,which is superior to those reported for the core-shell structured nanoparticles.The Coulombic Efficiency at the first cycle was 90.4%and kept stable at more than 99.0%after only 10 cycles.The capacity retention was nearly twice as that of the incompact mixture of Li-Si nanoparticles and carbon.The energy density of the full cell constructed by the present composite and sulfur was evaluated to be 3 times as high as that of the commercial lithium-ion batteries.This work provides a new universal strategy for developing Li-rich anode materials with high combination properties and low cost.

关键词： Li-Si alloy Three-dimensional carbon network Nano-domain Interface bond

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一种精密测量仪器的快速对接机构

宇航计测技术 2024年第2期44卷 74-77页

作者：王军宋小艳张海燕北京航天发射技术研究所北京100076

为了保证两精密测量仪器快速对接与分离的高精密性和稳定性,设计了一种高精密重复定位的快速对接机构。采用三点支撑[1]的方式,保证需要对接的两仪器拥有较高的重复定位误差,并且误差恒定。通过紧扣机构和旋钮构成对接紧扣装置,实现两... 详细信息

为了保证两精密测量仪器快速对接与分离的高精密性和稳定性,设计了一种高精密重复定位的快速对接机构。采用三点支撑[1]的方式,保证需要对接的两仪器拥有较高的重复定位误差,并且误差恒定。通过紧扣机构和旋钮构成对接紧扣装置,实现两仪器六自由度锁紧的高可靠性和稳定性,并且实现对接与分离的快速性。设计安装限位功能,以保证安装位置的重复性。分析了对接机构原理,并对重复定位误差的不确定度因素进行了简要分析。最后,通过设计试验来检测两精密测量仪器重复定位的误差,试验结果表明,快速对接机构具有较高的重复定位误差,证明设计合理。

关键词：重复定位三点支撑快速对接锁紧

Effect of Carbon Addition on Microstructure and Properties of WC-Co Cemented Carbides

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Journal of Materials Science & Technology 2012年第9期28卷 837-843页

作者： Chongbin Wei xiaoyan song Jun Fu Xiaosen Lv Haibin Wang Yang Cao ShixianZhao Xuemei Liu College of Materials Science and Engineering Key Lab of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 100124China Beijing Belying Hardalloy Co. Ltd.Beijing 100055China

Based on a unique method to synthesize WC-Co composite powder by in-situ reactions of metal oxides and carbon, the effects of the carbon addition in the initial powders on the phase constitution, microstructure and mechanical properties of the cemented carbides were investigated. It is found that with a suitable carbon addition the pure phase constitution can be obtained in the sintered bulk from the composite powder. The mechanical properties of the cemented carbides depend on the phase constitution and the WC grain structure. To obtain the excellent properties of the WC-Co bulk, it is important to obtain the pure phase constitution from the appropriate carbon addition in the initial powders and a suitable grain size.

关键词： Cemented carbides Carbon addition Composite powder Phase constitution Mechanical property

河南省应用型本科高校数字化教育资源共建共享现状研究

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太原城市职业技术学院学报 2024年第6期 56-58页

作者：宋晓燕郑州经贸学院河南郑州451191

近年来,中国高校数字化教育资源共享得到了长足发展。许多高校建立了自己的数字化教育资源共享平台,但跟国外相比,国内高校教育资源建设普遍落后,各层次教育资源的发展良莠不齐。文章基于目前高校数字化教育资源共享现状,进行了实证问... 详细信息

近年来,中国高校数字化教育资源共享得到了长足发展。许多高校建立了自己的数字化教育资源共享平台,但跟国外相比,国内高校教育资源建设普遍落后,各层次教育资源的发展良莠不齐。文章基于目前高校数字化教育资源共享现状,进行了实证问卷调查,发现其中存在的问题并给出解决方案,为后续高校数字化教育资源科学发展提供指导。

关键词：数字化教育资源共建共享高校