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基于机制砂棱角性表征的级配测量修正方法及实验研究

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仪表技术与传感器 2024年第4期 81-89页

作者：潘维俊房怀英杨建红黄斐智华侨大学机电及自动化学院

机制砂的形状特征和级配对混凝土性能有着重要影响,图像法可以同时测量颗粒的形态和级配。在机制砂的级配测量中,需要考虑颗粒的形态特征对级配的影响。因此,提出利用图像分析技术实现机制砂棱角性的表征和级配测量修正,分别进行了机制... 详细信息

机制砂的形状特征和级配对混凝土性能有着重要影响,图像法可以同时测量颗粒的形态和级配。在机制砂的级配测量中,需要考虑颗粒的形态特征对级配的影响。因此,提出利用图像分析技术实现机制砂棱角性的表征和级配测量修正,分别进行了机制砂的棱角性对比实验,级配重复性实验,图像法与筛分法级配测量对比实验以及修正前后的对比实验。实验结果表明,拟合椭圆棱角性算法可以独立地表征棱角性,不受粒径大小的影响。等效Feret椭圆短径作为等效粒径,粒度区间最大重复性误差出现在1.18~2.36 mm的尺寸区间,为1.26%。图像法测量的最大级配误差从修正前的6.29%减少到修正后的1.01%,细度模数的最大误差从0.17降低到0.04。相比传统的筛分方法,该测量系统具有良好的稳定性和功能性,满足测量的标准和要求。

关键词：图像法棱角性级配机制砂修正

基于演化博弈的乡村创业生态系统价值共创演化机理研究

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商业观察 2024年第23期10卷 38-42,55页

作者：杜娟张怀英童子萍吉首大学商学院湖南湘西416000

价值共创是乡村创业生态系统的核心驱动力,文章运用动态视角的演化博弈和计算机仿真分析的方法,考察乡村创业生态系统主体间价值共创的动态演化过程。研究结论表明:在乡村创业生态系统中,创业企业和相关主体在决定是否参与价值共创策略... 详细信息

价值共创是乡村创业生态系统的核心驱动力,文章运用动态视角的演化博弈和计算机仿真分析的方法,考察乡村创业生态系统主体间价值共创的动态演化过程。研究结论表明:在乡村创业生态系统中,创业企业和相关主体在决定是否参与价值共创策略时,会考虑到一个平衡点,被称为ESS点,它长期表现出动态稳定性。博弈双方选择策略的稳定性与动态方程参数的变化密切相关,选择参与价值共创策略的稳定性与成本呈反比关系,而与协同收益成正比,也就是说,当双方投入成本较低而协同收益较高时,双方参与价值共创策略的选择将在长期内保持相对稳定。

关键词：乡村创业生态系统价值共创演化博弈计算机仿真

Effect of lime application on microbial community in acidic tea orchard soils in comparison with those in wasteland and forest soils

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Journal of Environmental Sciences 2010年第8期22卷 1253-1260页

作者： Dong Xue Xiangdong Huang huaiying Yao Changyong Huang Zhejiang Provincial Key Laboratory of Subtropic Soil and Plant Nutrition College of Environmental and Resource Sciences Zhejiang University (Huajiachi Campus) Hangzhou 310029 China Department of Environmental and Chemical Engineering Luoyang Institute of Science and Technology Luoyang 471023 China

Lime application is a conventional technology to control acidification in tea orchard soils. We investigated the effect of lime application on soil microbial community diversity in the soils of three tea orchards, wasteland and forest. The BIOLOG data showed that both the average well color development of all carbon sources and the functional diversity index increased with the liming rate in the tea orchards and the forest, but decreased in the wasteland. The phospholipid fatty acid （PLFA） analysis showed that the structural diversity index of soil microbial community increased with the liming rate in all the tea orchards, the wasteland and the forest. Lime application also increased the soil-bacterial PLFA content in all the soils. Soil fungal and actinomycete PLFAs in the tea orchards showed an increasing trend from 0 to 3.2 g CaCO 3 /kg application and then a decreasing trend from 3.2 to 6.4 g CaCO 3 /kg application. The principal component analysis of BIOLOG and PLFA data suggested that lime application had a significant effect on soil microbial community structure, and land use had a greater effect on soil microbial community structure compared to lime application.

关键词： microbial community diversity phospholipid fatty acid lime tea orchard soil

Nitrification potentials of Chinese tea orchard soils and their adjacent wasteland and forest soils

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Journal of Environmental Sciences 2009年第9期21卷 1225-1229页

作者： XUE Dong GAO Yangmei YAO huaiying HUANG Changyong Zhejiang Provincial Key Laboratory of Subtropic Soil and Plant Nutrition College of Environmental and Resource Sciences Zhejiang University (Huajiachi Campus) Hangzhou 310029 China. Department of Environmental and Chemical Engineering Luoyang Institute of Science and Technology Luoyang 471023 China

To investigate the nitrifying activities of different soil types, soil samples collected from 8-, 50- and 90-year old tea orchards, the adjacent wasteland, and 90-year old forest were measured for their nitrification potentials using the conventional soil incubation and the liquid incubation method. Among different soil types, the nitrification potential of soil in tea orchards was higher than that of wasteland and forest soils. The slurry shaken liquid incubation method was confirmed to be more accurate and have reliable results than the soil incubation. Interestingly, experimental result revealed that the generally applied pH value of 7.2 for the liquid media was not the optimal pH for these acid soils with a strong buffer capacity. This suggested that tea orchard soils may have nitrifiers requiring pHneutral condition for the best activity. Our data also showed that treatment with the commonly used nitrogen fertilizer urea significantly improved nitrification potential of the soils; such enhancement effect was stronger on all of three tea orchard soils than on wasteland and forest soils, and also stronger on the younger （8- and 50-year old） tea orchard soils than on the older one （90-year old）.

关键词： tea orchard wasteland forest nitrification potential urea

Polyoxometalates-based heterogeneous catalysts in acid catalysis

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Science China Chemistry 2021年第7期64卷 1117-1130页

作者： Lifei Lian huaiying Zhang Sai An Wei Chen Yu-Fei Song State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Acid catalysis,one of the most important industrial processes,suffers from the toxicity,corrosion and recyclability problems of conventional homogeneous acid ***,the development of green heterogeneous acid catalysts becomes the focus of fundamental research and industrial *** a class of discrete anionic metal-oxygen clusters with tunable structure at the molecular and atomic scales,polyoxometalates(POMs)benefit from their super strong Br?nsted acidity,high proton mobility,and thermal ***-based heterogeneous catalysts have been used as the potential green alternatives to conventional homogeneous acid *** this review,we summarize recent progress on the design strategies of the POMs-based heterogeneous catalysts and their catalytic properties in acid-catalyzed reactions,where they are combined with functionalized cations,modified through covalent interactions,supported onto the non-precious metal support,and introduced into the framework of porous *** design,functional strategies and catalytic performance of these POMs-based heterogeneous catalysts in specific acid-catalyzed reactions are emphasized.

关键词： polyoxometalates solid acid catalyst acid catalysis heterogeneous catalysis esterification

鸡传染性喉气管炎病毒SYBR Green Ⅰ实时荧光定量PCR检测方法的建立与应用

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山东农业科学 2024年第6期56卷 128-132页

作者：张玉霞董雯雯袁小远孟凯徐怀英山东省农业科学院家禽研究所山东济南250100

鸡传染性喉气管炎病毒(Infectious laryngotracheitis virus,ILTV)以往多感染蛋鸡,近年来在蛋种鸡、商品肉鸡中连续多发,表明该病毒感染谱有扩大风险,因此有必要加强对ILTV的监测。为建立高效、灵敏的ILTV检测方法,本研究以ILTV的TK基... 详细信息

鸡传染性喉气管炎病毒(Infectious laryngotracheitis virus,ILTV)以往多感染蛋鸡,近年来在蛋种鸡、商品肉鸡中连续多发,表明该病毒感染谱有扩大风险,因此有必要加强对ILTV的监测。为建立高效、灵敏的ILTV检测方法,本研究以ILTV的TK基因为靶基因设计引物,扩增并构建pMD18-T-TK质粒标准品,建立SYBR GreenⅠ实时荧光定量PCR检测方法和标准曲线,对其特异性、敏感性和重复性进行验证,并对临床疑似病例进行检测。结果发现,该检测方法特异性良好,与其他常见症状相似病原无交叉反应;最低检测浓度为1.55拷贝/μL,灵敏度是普通PCR方法的10倍;重复性好,批内、批间变异系数在0.79%~1.83%之间。表明本研究建立的ILTV实时荧光定量PCR方法特异性强、灵敏度高,可为ILTV的临床诊断和流行病学研究等提供有效的检测方法。

关键词：鸡喉气管炎病毒 TK基因实时荧光定量PCR 特异性敏感性重复性

维普期刊数据库博看期刊

Effect of wheel speed on phase formation and magnetic properties of (Nd_(0.4)La_(0.6))-Fe-B melt-spun ribbons

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Journal of Rare Earths 2018年第11期36卷 1179-1183页

作者： Liang Wang Jiang Wang Maohua Rong Guanghui Rao huaiying Zhou School of Material Science and Engineering & Guangxi Key Laboratory of Information Materials Guilin University of Electronic Technology Guilin 541004China

The effect of wheel speed on phase formation and magnetic properties of （Ndo.4La0.6）lsFeTzsBzs and （Ndo.4La0.6）13.4Fe79.9B6.7 ribbons prepared by melt-spinning method was investigated experimentally. Based on X-ray diffraction results, all melt-spun ribbons consist of the main phase with the tetragonal 2：14：1 type structure and the minor α-Fe phase. Magnetic measurements show the maximum magnetic energy product （（BH）max） and the remanence （Mr） increases firstly and then decreases with the increase of wheel speed, while the coercivity （Hci） increases, resulting from the variation of the average volume fraction of the ^-Fe phase and the average grain size in the melt-spun ribbons. Using Henkel plots, the interaction between the 2：14：1 phase and the ^-Fe phase in the melt-spun ribbons was analyzed and the intergranular exchange coupling is manifested. Optimal magnetic properties of Hci - 7.27 kOe, Mr - 90.94 emu/g and （BH）max -- 12.10 MGOe are achieved in the （Ndo.4La0.6）lsFeTzsBT.s ribbon with the wheel speed of 26 m/s. It indicates that magnetic properties of Nd-Fe-B melt-spun ribbons with highly abundant rare earth element La can be improved by optimizing alloy composition and preparation process.

关键词： Nd-La-Fe-B ribbons Phase formation Melt-spinning Magnetic properties Rare earths

Main environmental drivers of abundance,diversity and community structure of comammox Nitrospira in paddy soils

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Pedosphere 2023年第5期33卷 808-818页

作者： Fuyun GAO Yaying LI Haoxin FAN Jiantao XUE huaiying YAO Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control CAS Haixi Industrial Technology Innovation Center in BeilunNingbo 315800China University of Chinese Academy of Sciences Beijing 100049China Research Center for Environmental Ecology and Engineering School of Environmental Ecology and Biological EngineeringWuhan Institute of TechnologyWuhan 430073China

The recently discovered complete ammonia oxidizers comammox Nitrospira contain clades A and B that can establish an independent one-step nitrification process;however,little is known about their environmental drivers or habitat distributions in agricultural *** studies on comammox Nitrospira in paddy soils have mainly focused on small-scale samples,and there is a lack of multisite research on comammox Nitrospira in paddy *** this study,we conducted a survey of 36 paddy soils to understand the community structure,abundance,and diversity of comammox Nitrospira and the degree to which they are affected by environmental factors at a large *** Nitrospira were found to be widely distributed among the paddy *** abundance of comammox Nitrospira clade A was mostly lower than that of clade B,whereas its diversity was mostly higher than that of clade *** analysis showed that multiple factors affected(P<0.05)the abundance of comammox Nitrospira,including soil pH,organic matter,total carbon,and total nitrogen,latitude,mean annual temperature,and mean annual ***,there was a clear relationship between the comammox Nitrospira community and habitat,indicating that some amplicon sequence variants(ASVs)had a unique dominant position in specific *** analysis showed that the ASVs of comammox Nitrospira clade A clustered with the known sequences in the paddy soils and were significantly different from the known sequences in other habitats,which may be related to the unique paddy field *** contrast,comammox Nitrospira clade B showed no clear habitat *** results support the wide distribution and high abundance of comammox Nitrospira in paddy soils and provide novel insights into nitrogen cycling and nutrient management in agricultural ecosystems.

关键词： ammonia-oxidizing archaea ammonia-oxidizing bacteria amplicon sequence variant complete ammonia oxidizer environmental factor habitat nitrification nitrogen cycling

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根际微生物增强水稻耐盐性研究进展

作物杂志 2024年第4期 8-13页

作者：顾怀应胡诗钦赵晴刘长华孟丽君黑龙江大学现代农业与生态环境学院黑龙江哈尔滨150080 佛山鲲鹏现代农业研究院广东佛山528225

土壤盐碱化对植物的生长发育造成不利影响,因而对水稻等盐敏感作物会造成严重的产量损失。随着对土壤中微生物认识的不断加深,根际微生物组在增加水稻耐盐性方面的能力已经得到证实。本文介绍了利用多组学研究微生物与水稻互作的概况、... 详细信息

土壤盐碱化对植物的生长发育造成不利影响,因而对水稻等盐敏感作物会造成严重的产量损失。随着对土壤中微生物认识的不断加深,根际微生物组在增加水稻耐盐性方面的能力已经得到证实。本文介绍了利用多组学研究微生物与水稻互作的概况、增强水稻耐盐性的根际微生物组以及盐胁迫下微生物增强水稻耐盐性的生理机制,并展望了微生物利用的研究方向,为揭示微生物增强水稻耐盐性的机理提供参考,为提高盐碱环境下水稻产量提供新的思路和方法。

关键词：水稻盐胁迫根际微生物生理机制