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GGE biplot analysis of yield stability and test location representativeness in proso millet (Panicum miliaceum L.) genotypes 被引量:14
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作者 ZHANG Pan-pan SONG Hui +8 位作者 KE Xi-wang JIN Xi-jun YIN Li-hua LIU Yang QU Yang SU Wang FENG Nai-jie ZHENG Dian-feng FENG Bai-li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第6期1218-1227,共10页
The experiments were conducted for three consecutive years across 14 locations using 9 non-waxy proso millet genotypes and 16 locations using 7 waxy proso millet genotypes in China. The objectives of this study were t... The experiments were conducted for three consecutive years across 14 locations using 9 non-waxy proso millet genotypes and 16 locations using 7 waxy proso millet genotypes in China. The objectives of this study were to analyze yield stability and adaptability of proso millets and to evaluate the discrimination and representativeness of locations by analysis of vari- ance (ANOVA) and genotype and genotype by environment interaction (GGE) biplot methods. Grain yields of proso millet genotypes were significantly influenced by environment (E), genotype (G) and their interaction (GxE) (P〈0.1%). GxE inter- action effect was six times higher than G effect in non-waxy group and seven times in waxy group. N04-339 in non-waxy and Neimi 6 (NM6) in waxy showed higher grain yields and stability compared with other genotypes. Also, Neimi 9 (NM9, a non-waxy cultivar) and 90322-2-33 (a waxy cultivar) showed higher adaptability in 7 and in 11 locations, respectively. For non-waxy, Dalat, Inner Mongolia (E2) and Wuzhai, Shanxi (E5) were the best sites among all the locations for maximizing the variance among candidate cultivars, and Yanchi, Ningxia (El0) had the best representativeness. Wuzhai, Shanxi (e9) and Yanchi, Ningxia (e14) were the best representative locations, and Baicheng, Jilin (e2) was better discriminating location than others for waxy genotypes. Based on our results, El0 and e14 have enhanced efficiency and accuracy for non-waxy genotypes and waxy genotypes selection, respectively in national regional test of proso millet varieties. 展开更多
关键词 proso millet GGE biplot yield stability test location representativeness
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Influence of Humidity on Yield Stress Determination by Slump Test of Slip-Prone Clayey Soils and Their Relation with the Chemical Properties
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作者 Arturo F. Méndez-Sánchez Ana M. Paniagua-Mercado +3 位作者 Karen E. Nieto-Zepeda Leonor Pérez-Trejo Elvia Diaz Valdés Concepción Mejía García 《Advances in Materials Physics and Chemistry》 2012年第4期102-105,共4页
In this work, the yield stress evaluation as a function of water content for slip-prone clayey soils is studied in order to understand how yield stress decreases as water content increases, and their relation with the... In this work, the yield stress evaluation as a function of water content for slip-prone clayey soils is studied in order to understand how yield stress decreases as water content increases, and their relation with the chemical properties. The clayey soil samples were taken from the region of Teziutlán-Puebla-Mexico. Yield stress was calculated using the slump test in cylindrical geometry. Results show three zones. The first one shows an exponential decrement on yield stress due to lower water content in accord with clayey soils with high content of illita, followed by a second region where yield stress decreases dramatically at a certain critical water concentration, and the third one where yield stress dependence is not well-defined since the clayey soil flow is seen. Finally, it is discussed how yield stress variation due to the water increment influences the landslide risk increment. 展开更多
关键词 Clayey SOIL yield Stress SLUMP test Microstructure Illita
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Use of Random Regression Test-Day Model to Estimate Genetic Parameters of Milk Yield in Holstein Cows
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作者 Yaser Fazel Masoud Asadi Fozi +4 位作者 Ali Esmailizadeh Fatemeh Fazel Ahmad Massoud Niazi Shahpoor Rahmati Mohammad Ibrahim Qasimi 《Open Journal of Animal Sciences》 2018年第1期27-38,共12页
(Co) variance components and genetic parameters were estimated for milk yield of Iranian Holstein cows. A total number of 68,945 milk test-day records of first, second and third lactations of 8515 animals from 100 sir... (Co) variance components and genetic parameters were estimated for milk yield of Iranian Holstein cows. A total number of 68,945 milk test-day records of first, second and third lactations of 8515 animals from 100 sires and 7743 dams originated from 34 herds collected during 2007 to 2009 by Iranian animal breeding center were used. The ASReml computer program was used to analyze the milk test-day records using the random regression procedure. Herd test date (HTD), milking times per day (milking frequency), number of lactations, year of birth, year of calving, age of animal at calving and days in milk (DIM) considered as fixed effects and additive genetic effects and animal permanent environmental effects were considered as the random effects. Additive genetic variance, animal permanent environment variance, residual variance, phenotypic variance, heritability and repeatability were estimated during different months of lactation between 5.7 - 19.6, 15.3 - 27.1, 31.4 - 17.2, 45.8 - 64.83, 0.1 - 0.32 and 0.4 - 0.6, respectively. Genetic correlation and phenotypic correlation were also estimated between months of lactation in range of -0.35 - 0.98 and 0.03 - 0.67, respectively. Genetic correlation and phenotypic correlation both showed the same changing pattern and they decreased as the interval between months of lactation increased. 展开更多
关键词 GENETIC Parameters Random Regression Model test-Day RECORDS MILK yield HOLSTEIN COWS
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超声波-高压咖啡冷萃系统工艺设计与试验
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作者 苏微 翟国栋 +4 位作者 赖庆辉 董文江 张玉凝 阙煜 王晓阳 《农机化研究》 北大核心 2026年第3期202-210,共9页
针对传统冷萃工艺耗时、设备效率不足和冷萃咖啡关键制备工艺不成熟等问题,结合超声波萃取技术和高压萃取技术,设计和开发了一种超声波-高压咖啡冷萃系统和工艺。通过在萃取釜上增设可拆卸超声振动组件,将超声波萃取技术和高压萃取技术... 针对传统冷萃工艺耗时、设备效率不足和冷萃咖啡关键制备工艺不成熟等问题,结合超声波萃取技术和高压萃取技术,设计和开发了一种超声波-高压咖啡冷萃系统和工艺。通过在萃取釜上增设可拆卸超声振动组件,将超声波萃取技术和高压萃取技术在同一个容器中进行,缩短萃取工作时长,提高咖啡冷萃效率。利用单因素试验和混合水平正交试验,对超声波冷萃咖啡进行萃取率检测,确定处理1 kg咖啡粉萃取率的最佳超声参数方案为萃取时间30 min、功率1 800 W、频率20 kHz。在咖啡萃取率最佳超声方案的基础上,进行整机萃取试验,结果表明:萃取率随压力增加和萃取时间延长呈上升趋势,其中10~20 min内增速较好,超过20 min后萃取率超过20%,压力在0.6~0.8 MPa区间内萃取率提升显著,0.8 MPa以上增速趋缓;选用萃取压力和萃取时间作为因素进行均匀设计试验,结果表明:最优压力萃取参数为压力1.2 MPa、压力萃取时间10 min。研究可为咖啡精深加工和高值化产品研发提供理论依据和技术支撑。 展开更多
关键词 冷萃咖啡 超声波萃取 高压萃取 萃取率 混合水平正交试验 均匀设计试验
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利尿消炎合剂提取工艺优选
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作者 张飞 高珊 +2 位作者 李卓亚 刘锐锋 赵伟国 《中国药业》 2026年第3期73-76,共4页
目的优化利尿消炎合剂的提取工艺。方法以浸泡时间、加水量、煎煮时间、煎煮次数为考察因素,以盐酸小檗碱转移率和出膏率为综合评价指标,采用L_(9)(3^(4))正交试验法优选利尿消炎合剂的提取工艺,并进行验证。结果最佳提取工艺为加10倍量... 目的优化利尿消炎合剂的提取工艺。方法以浸泡时间、加水量、煎煮时间、煎煮次数为考察因素,以盐酸小檗碱转移率和出膏率为综合评价指标,采用L_(9)(3^(4))正交试验法优选利尿消炎合剂的提取工艺,并进行验证。结果最佳提取工艺为加10倍量水,浸泡1.0 h,煎煮3次,每次1.5 h。按此工艺制备的3批样品中,平均盐酸小檗碱转移率为15.99%,平均出膏率为17.73%。结论优选工艺稳定、合理、可行,可用于利尿消炎合剂的制备。 展开更多
关键词 利尿消炎合剂 L_(9)(3^(4))正交试验法 盐酸小檗碱 转移率 出膏率 提取工艺
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Initial Field Evaluation of the Agro-Economic Effects of Determining Nitrogen Fertilizer Rates with a Recently-Developed Soil Test Methodology 被引量:1
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作者 R. Daren Harmel Richard L. Haney 《Open Journal of Soil Science》 2013年第2期91-99,共9页
Although agriculture is not the only contributor of excess nutrients to US waters, agriculture is an important contributor and should do its part to reduce nutrient loading. One important step in reducing agricultural... Although agriculture is not the only contributor of excess nutrients to US waters, agriculture is an important contributor and should do its part to reduce nutrient loading. One important step in reducing agricultural contribution is to accurately account for all sources of plant available nutrients so that only needed nutrients are applied. In this study, three fertilizer rate treatments were evaluated: no fertilizer (control), traditional rate, and reduced rate based on a recently-developed enhanced soil test methodology. For each of nine sites in Texas, fertilizer data (formulation, rate, cost, and application date) and crop data (yield, price, and harvest date) were recorded, and economic throughput (profit) was determined. In this four year study, fertilizer rates were reduced 30%-50% (and fertilizer costs reduced 23%-39%) based on enhanced soil test methodology recommendations for wheat, corn, oats, and grain sorghum, but yields were not significantly reduced (0%-6%) and oat yields actually increased 5%. Profit decreased -18% for wheat, oats, and grain sorghum with reduced fertilizer rates. Although these changes were not statistically significant, they do represent benefit through increased profit potential and decreased input cost and production risk. In only 6% of the time was the traditional fertilizer rate the most profitable, compared to 51% for the unfertilized treatment and 43% for the enhanced soil test treatment. These results do not indicate that fertilizer application should be avoided but that fertilizer rates should be carefully chosen considering all sources of plant available nutrients (e.g., mineralization, irrigation water, nutrients deeper in the soil profile) to ensure that fertilizer is applied at the optimal rate. 展开更多
关键词 Soil tests CROP yieldS ON-FARM PROFIT Water Quality
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Screening Test of Maize Varieties in Mountainous Arid Areas
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作者 Xiaojun GUO Ping WANG +3 位作者 Chengjun XIE Guoyu WANG Jianping HU Long WEI 《Asian Agricultural Research》 2018年第1期48-50,共3页
Drought and water shortage are the biggest limiting factors of dry farming,and variety plays an important role in an increase in the yield of dryland maize.Screening high-yield maize varieties is helpful to the contin... Drought and water shortage are the biggest limiting factors of dry farming,and variety plays an important role in an increase in the yield of dryland maize.Screening high-yield maize varieties is helpful to the continuous increase and stable yield of dryland grain.In this experiment,the growth period,characters and yield of 12 maize varieties were analyzed.The results show that the yield of Ganyu series was low,while the yield of Lianda 169 was the highest(8 080.93 kg/ha),which was 31.40% higher than Jinsui 4.The yield of Dunyu 16 was6 621.06 kg/ha,7.64% higher than Jinsui 4.The two varieties had good comprehensive characters,so they could be popularized and planted in dry farming areas of Lanzhou City. 展开更多
关键词 DROUGHT Maize varieties yield Variety test
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Biaxial tensile behavior and yield loci of dual-phase steel sheets 被引量:2
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作者 Zhao-xuan Hou Min Wan +3 位作者 Xiang-dong Wu Zheng-yang Cai Xue-li Gong Hao Wang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2018年第5期589-597,共9页
The biaxial tensile tests were carried out to investigate the deformation behavior and yield loci of dual-phase (DP) steel sheets under biaxial tensile conditions. The true stress-true strain curves of DP steel shee... The biaxial tensile tests were carried out to investigate the deformation behavior and yield loci of dual-phase (DP) steel sheets under biaxial tensile conditions. The true stress-true strain curves of DP steel sheets for different loading ratios were obtained, and the experimental yield loci were determined based on the equivalent plastic work principle. The experimental yield loci were compared to the theoretical yield loci based on Hi1148, Hi1190, Hi1193, Hosford, Barlat89, Yld2000-2d and Gotoh yield criteria. It is found that Yld2000-2d yield criterion can describe the general trends of experimental yield loci of DP steel sheets with comparably higher accuracy. Hosford criterion has the maximum error for DP590, whereas Hi1148 and Barlat89 have the maximum errors for DP780 and DP980. 展开更多
关键词 Dual-phase steel sheet ·Biaxial tensile test Loading ratio yield locus Yld2000-2d yield criterion
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A METHOD TO QUANTIFY CRAZING DEFORMATION BY TENSILE TESTS FOR POLYSTYRENE/POLYOLEFIN ELASTOMER IMMISCIBLE BLENDS
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作者 方征平 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第4期387-392,共6页
A method to quantify crazing deformations by tensile tests for polystyrene (PS) and polyolefin elastomer (POE) blends was investigated. The toughness of PS/POE blends, reflected by the Charpy impact strength, incr... A method to quantify crazing deformations by tensile tests for polystyrene (PS) and polyolefin elastomer (POE) blends was investigated. The toughness of PS/POE blends, reflected by the Charpy impact strength, increased with the content of POE. SEM micrographs showed the poor compatibility between PS and POE. In simple tensile tests, it is very easy to achieve the ratio of crazing deformation, i.e. K by measuring the size changes of samples. The K values decreased with increasing the content of POE, and the deformations of PS/POE blends were dominated by crazing. The plots of the change of volume (△V) against longitudinal variation (△I) showed a linear relationship, and the slope of lines decreased with the content of POE. Measuring samples at the tensile velocities of 5 mm/min, 50 mm/min, and 500 mm/min respectively, the K values kept unchanged for each PS/POE blends. 展开更多
关键词 Crazing deformation Shear yielding deformation Tensile test Polystyrene (PS) Polyolefin elastomer (POE) Blend.
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Evaluation of Soil Potassium Test to Improve Fertilizer Recommendations for Corn 被引量:1
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作者 Manbir K. Rakkar David W. Franzen Amitava Chatterjee 《Open Journal of Soil Science》 2015年第5期110-122,共13页
The soil potassium (K) test methodology is under increased evaluation due to the soil sample drying effect, temporal variations of test results and inconsistent crop response to applied K fertilizers. Ten on-farm tria... The soil potassium (K) test methodology is under increased evaluation due to the soil sample drying effect, temporal variations of test results and inconsistent crop response to applied K fertilizers. Ten on-farm trials were conducted in 2014 in eastern North Dakota to determine the corn response to different K-fertilizer rates and to assess the variation of soil K test levels between air-dried (KDry) and field moist (KMoist) soil samples during the corn growing season. Significant differences were observed between KDry and KMoist soil K test results. The ratio of KDry/KMoist showed high correlation with cation exchange capacity (r = 0.63, p < 0.10), Organic matter (r = 0.61, p < 0.10) and (Ca + Mg)/K ratio (r = 0.64, p < 0.10) from the 1 M ammonium acetate extractant, while pH, electrical conductivity, clay (%), and soil moisture showed non-significant correlation. On average, KDry resulted in higher soil K test levels than KMoist and pattern of deviation was different for surface and sub-surface soil samples. Soil K analysis of samples collected during the fall and spring showed large enough variations to affect the soil test interpretation category which was used to make fertilizer recommendations. Corn yield increased significantly with applied K fertilizer at only three out of 8 sites with beginning K levels below the current critical level of 150 ppm, and one response was at a site with K level above the critical level. Therefore, use of either the KDry or KMoist method alone may not be adequate to predict K response in some North Dakota soils. 展开更多
关键词 POTASSIUM Soil test Methodology FERTILIZER RECOMMENDATIONS GRAIN yield
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江苏省糯玉米品种产量和品质性状及试点鉴别力分析 被引量:1
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作者 李小珊 黄忠勤 +1 位作者 刘红伟 苏在兴 《玉米科学》 北大核心 2025年第1期37-45,共9页
以2021-2022年江苏省区域试验中25个糯玉米品种在9个试点的鲜穗产量和品质性状数据为研究对象,应用GGE双标图法分析糯玉米品种的产量及区域适应性,对试点的区分力和代表性进行评价。应用GYT双标图法分析糯玉米品种的品质性状、产量和品... 以2021-2022年江苏省区域试验中25个糯玉米品种在9个试点的鲜穗产量和品质性状数据为研究对象,应用GGE双标图法分析糯玉米品种的产量及区域适应性,对试点的区分力和代表性进行评价。应用GYT双标图法分析糯玉米品种的品质性状、产量和品种×性状间的互作特性,并对参试品种进行综合评价。结果表明,2021年复试品种浙糯208、糯YH1113综合表现优良;2022年复试品种润扬白糯具有较强的地域性,适宜在徐州、淮安等地种植。连甜糯909适应性较强,综合表现优良。泰兴和海门试点的代表性和鉴别力较强,是较为理想的试验点。 展开更多
关键词 糯玉米 试验点 GGE双标图 丰产性 适应性
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Stress—strain curves for different loading paths and yield loci of aluminum alloy sheets
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作者 吴向东 万敏 +1 位作者 韩非 王海波 《中国有色金属学会会刊:英文版》 CSCD 2006年第A03期1460-1464,共5页
To carry out biaxial tensile test in sheet metal, the biaxial tensile testing system was established. True stress—true strain curves of three kinds of aluminum alloy sheets for loading ratios of 4:1, 4:2, 4:3, 4:4, 3... To carry out biaxial tensile test in sheet metal, the biaxial tensile testing system was established. True stress—true strain curves of three kinds of aluminum alloy sheets for loading ratios of 4:1, 4:2, 4:3, 4:4, 3:4, 2:4 and 1:4 were obtained by conducting biaxial tensile test in the established testing systems. It shows that the loading path has a significant influence on the stress—strain curves and as the loading ratio increases from 4:1 to 4:4, the stress—strain curve becomes higher and n-value becomes larger. Experimental yield points for three aluminum alloy sheets from 0.2% to 2% plastic strain were determined based on the equivalent plastic work. And the geometry of the experimental yield loci were compared with the yield loci calculated from several existing yield criteria. The analytical result shows that the Barlat89 and Hosford yield criterion describe the general trends of the experimental yield loci of aluminum alloy sheets well, whereas the Mises yield criterion overestimates the yield stress in all the contours. 展开更多
关键词 应力分析 铝合金 应变 机械性能
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基于结构屈服压力的黄土湿陷性评价
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作者 李同录 田志奇 +2 位作者 曹雄 李萍 付昱凯 《工程地质学报》 北大核心 2025年第1期1-9,共9页
随着黄土地区工程建设层次和标准的提高,对黄土湿陷性评价提出了更高的要求。本文以城际铁路西安-韩城线合阳段的湿陷性黄土为研究对象,现场开挖一30m深的探井,按1m间距取样,通过双线法湿陷试验测得12.5~4000kPa下的天然与饱和黄土的压... 随着黄土地区工程建设层次和标准的提高,对黄土湿陷性评价提出了更高的要求。本文以城际铁路西安-韩城线合阳段的湿陷性黄土为研究对象,现场开挖一30m深的探井,按1m间距取样,通过双线法湿陷试验测得12.5~4000kPa下的天然与饱和黄土的压缩曲线,计算得到湿陷系数-压力曲线。从曲线上可以看出黄土湿陷系数随压力变化呈先增大后减小的趋势,湿陷系数随压力变化存在着一个峰值,与峰值湿陷系数相应的压力为天然黄土的结构屈服压力,湿陷起始压力为饱和黄土的结构屈服压力。为此提出用天然黄土结构屈服压力下的峰值湿陷系数评价黄土地基的湿陷量。同时发现,黄土湿陷性随深度的变异性大,湿陷性、非湿陷性及弱膨胀黄土在剖面上都有出现,当少量湿陷性土夹在非湿陷性或弱膨胀黄土之间时,湿陷变形可能被周围土层吸收,为此建议湿陷土层底界深度不宜按湿陷性土样的最大深度来确定,以湿陷性明显的土层底面确定较为合适。 展开更多
关键词 黄土 湿陷性 结构屈服压力 双线法 湿陷土层深度
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滇东光叶紫花苕品种比较试验报告
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作者 张昌兵 文兴金 +9 位作者 陈莉敏 罗欣 罗国清 周靖文 欧才龙 闫利军 李达旭 游明鸿 张健 张建波 《草学》 2025年第3期26-29,共4页
以国家审定品种凉山光叶紫花苕和原始群体为对照,在布拖县特木里镇开展了滇东光叶紫花苕新品系的品种比较试验。试验结果表明:滇东光叶紫花苕年均生育周期222.5d,分别比对照原始群体和凉山光叶紫花苕长4d和2.5d;干草产量为12459.95kg/hm... 以国家审定品种凉山光叶紫花苕和原始群体为对照,在布拖县特木里镇开展了滇东光叶紫花苕新品系的品种比较试验。试验结果表明:滇东光叶紫花苕年均生育周期222.5d,分别比对照原始群体和凉山光叶紫花苕长4d和2.5d;干草产量为12459.95kg/hm^(2),分别比对照原始群体和凉山光叶紫花苕增产14.17%和10.76%;茎叶比为1:1.41,比对照原始群体和凉山光叶紫花苕均小;总体上看滇东光叶紫花苕适应性强、产量高、叶量丰富,适宜在该区域推广。 展开更多
关键词 光叶紫花苕 品种比较试验 物候期 产量 茎叶比
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皖西大别山典型土地利用类型坡面产流产沙与氮磷流失特征
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作者 张艺 田昌园 +4 位作者 汪文 李嘉宁 汪军红 张晓霞 查同刚 《水土保持通报》 北大核心 2025年第4期62-70,共9页
[目的]探究不同坡度和不同土地利用类型条件下,径流冲刷对坡面产流产沙和氮磷流失的影响,以期为皖西大别山的水土流失治理提供理论支撑。[方法]选取皖西大别山区的安徽省霍山县江子河小流域典型土地利用类型(裸地、草地、茶园、林地和竹... [目的]探究不同坡度和不同土地利用类型条件下,径流冲刷对坡面产流产沙和氮磷流失的影响,以期为皖西大别山的水土流失治理提供理论支撑。[方法]选取皖西大别山区的安徽省霍山县江子河小流域典型土地利用类型(裸地、草地、茶园、林地和竹林)的15°和20°坡面进行野外原位放水冲刷试验,基于该区域多暴雨的特点,设置冲刷流量为9 L/min,以探究坡面产流产沙和养分流失对土地利用类型和坡度的响应。[结果]①在放水冲刷过程中,15°坡面产流稳定时,平均产流率表现为:裸地>茶园>草地>林地>竹林,20°坡面产沙率表现为:裸地>草地>茶园>林地>竹林;相较于15°,在20°坡面除裸地产流率有明显增加以外,其余土地利用类型坡面变化不明显;当坡面产沙稳定时,20°坡面产沙率略高于15°坡面,且均表现为:裸地>茶园>草地>竹林>林地;②20°坡面的TN,TP流失量相较于15°坡面流失量略有增加,在同一坡度条件下,TN,TP流失规律为:茶园>裸地>竹林>草地>林地。③整个冲刷过程中,径流对全氮贡献率较高,泥沙对全磷的贡献率相对较高。[结论]在皖西大别山区扩大竹林面积能有效提升水源涵养和水土保持功能,在面源污染防治中,应对茶园进行重点管理,以减少氮磷等养分的流失。 展开更多
关键词 皖西大别山 冲刷试验 坡面产流产沙 养分流失
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室温拉伸试验方法实践探讨
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作者 李军伟 王丽晖 +3 位作者 赵启斌 潘英胜 冷松洋 吕政赫 《鞍钢技术》 2025年第1期67-71,共5页
阐述了2021版金属材料室温拉伸试验变更的主要内容,并对试验中出现的常见问题进行了原因分析,同时给出了切实可行的解决措施:对于呈现连续屈服的材料,方法A1、A2均可采用。对于呈现不连续屈服或在加工硬化阶段呈锯齿状的材料,应该采用... 阐述了2021版金属材料室温拉伸试验变更的主要内容,并对试验中出现的常见问题进行了原因分析,同时给出了切实可行的解决措施:对于呈现连续屈服的材料,方法A1、A2均可采用。对于呈现不连续屈服或在加工硬化阶段呈锯齿状的材料,应该采用开环的位移控制,推荐采用方法A2;若试验机在控制软件上设置了引伸计控制向横梁控制转变的转变点,且引伸计并不脱离应变跟踪,把该转变点设置在屈服之前,仍可采用方法A1进行测试。弹性模量的测试结果对塑性屈服强度影响不是很大。 展开更多
关键词 室温拉伸试验 引伸计 屈服强度 弹性模量
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Fuzzy Varying Coefficient Bilinear Regression of Yield Series
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作者 Ting He Qiujun Lu 《Journal of Data Analysis and Information Processing》 2015年第3期43-54,共12页
We construct a fuzzy varying coefficient bilinear regression model to deal with the interval financial data and then adopt the least-squares method based on symmetric fuzzy number space. Firstly, we propose a varying ... We construct a fuzzy varying coefficient bilinear regression model to deal with the interval financial data and then adopt the least-squares method based on symmetric fuzzy number space. Firstly, we propose a varying coefficient model on the basis of the fuzzy bilinear regression model. Secondly, we develop the least-squares method according to the complete distance between fuzzy numbers to estimate the coefficients and test the adaptability of the proposed model by means of generalized likelihood ratio test with SSE composite index. Finally, mean square errors and mean absolutely errors are employed to evaluate and compare the fitting of fuzzy auto regression, fuzzy bilinear regression and fuzzy varying coefficient bilinear regression models, and also the forecasting of three models. Empirical analysis turns out that the proposed model has good fitting and forecasting accuracy with regard to other regression models for the capital market. 展开更多
关键词 FUZZY VARYING COEFFICIENT BILINEAR Regression Model FUZZY Financial Assets yield LEAST-SQUARES Method Generalized Likelihood Ratio test Forecast
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免疫抑制剂环孢菌素A高产菌株发酵中试放大研究 被引量:1
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作者 林仙菊 张祝兰 +4 位作者 温耀明 严凌斌 邱观荣 黄洪祥 连云阳 《药物生物技术》 2025年第1期14-20,共7页
以实验室筛选得到的产环孢菌素A高产菌株雪白白僵菌FIM-1809-7为研究对象,确定其中试发酵放大工艺及生产水平。采用单因素试验研究环孢菌素A最佳发酵工艺条件,并通过中试放大100 L及1吨发酵罐验证其发酵生产水平。结果确定最佳发酵工艺... 以实验室筛选得到的产环孢菌素A高产菌株雪白白僵菌FIM-1809-7为研究对象,确定其中试发酵放大工艺及生产水平。采用单因素试验研究环孢菌素A最佳发酵工艺条件,并通过中试放大100 L及1吨发酵罐验证其发酵生产水平。结果确定最佳发酵工艺条件:种子菌龄72 h,种子装料系数250 mL每2 L,二级种子接种量0.2%~0.4%,发酵接种量10~15%,发酵pH 5.6,消泡剂泡敌添加量0.05%,发酵周期7 d。并通过5批次中试1吨发酵罐放大生产发酵环孢菌素A,其效价水平略有波动,效价平均值达到11913μg/mL,最高效价值可达到12586μg/mL。通过本试验建立雪白白僵菌FIM-1809-7稳定生产环孢菌素A中试发酵工艺,为环孢菌素A的工业化生产应用奠定了基础。 展开更多
关键词 雪白白僵菌 环孢菌素A 免疫抑制剂 发酵 高产 中试放大
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微磁检测技术在Cr12MoV钢和3Cr13钢屈服/抗拉强度检测中的应用
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作者 王贤贤 何存富 +3 位作者 刘秀成 李鹏 宁梦帅 邢智翔 《北京工业大学学报》 CAS 北大核心 2025年第1期32-41,共10页
利用微磁无损检测方法对Cr12MoV钢和3Cr13钢的屈服强度(R_(p0.2))和抗拉强度(R_(m))进行无损定量预测。首先,采用先淬火后回火的工艺改变材料的拉伸力学性能,得到不同屈服/抗拉强度的拉伸试样;其次,对2种材料先后进行微磁特征参量测试... 利用微磁无损检测方法对Cr12MoV钢和3Cr13钢的屈服强度(R_(p0.2))和抗拉强度(R_(m))进行无损定量预测。首先,采用先淬火后回火的工艺改变材料的拉伸力学性能,得到不同屈服/抗拉强度的拉伸试样;其次,对2种材料先后进行微磁特征参量测试和屈服/抗拉强度的测定;然后,分别利用格拉布斯(Grabbs)准则和ReliefF特征筛选方法,剔除系统误差并得到对强度指标敏感的微磁特征参量;最后,通过神经网络模型寻优,构建BP神经网络预测模型,实现Cr12MoV钢和3Cr13钢屈服强度和抗拉强度定量预测。研究结果表明:微磁检测方法可以对Cr12MoV钢和3Cr13钢屈服强度和抗拉强度进行无损定量预测,模型得到的屈服强度和抗拉强度预测平均误差分别小于3%和5%。提出的研究方法和结论可为铁磁性材料屈服强度和抗拉强度的微磁无损检测提供参考。 展开更多
关键词 微磁检测 抗拉强度 屈服强度 BP神经网络 无损检测 RELIEFF
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饱和软黏土的ESF弹塑性模型及其验证
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作者 徐日庆 俞天赐 +3 位作者 吴明明 张岗平 鞠露莹 徐启良 《湖南大学学报(自然科学版)》 北大核心 2025年第3期151-160,共10页
为描述饱和软黏土的强度变形特性并解决传统弹塑性模型中屈服面角点处塑性应变增量方向不够明确的问题,建立了一种饱和软黏土的蛋形屈服面弹塑性本构模型.首先,基于蛋形函数(ESF),采用相关联流动法则,以塑性体应变作为内变量,建立了饱... 为描述饱和软黏土的强度变形特性并解决传统弹塑性模型中屈服面角点处塑性应变增量方向不够明确的问题,建立了一种饱和软黏土的蛋形屈服面弹塑性本构模型.首先,基于蛋形函数(ESF),采用相关联流动法则,以塑性体应变作为内变量,建立了饱和软黏土的ESF弹塑性模型.模型通过引入封闭光滑的蛋形屈服面,克服了传统屈服面的角点缺陷.通过调整蛋形形状控制参数,将屈服面灵活转化为包括子弹形、椭圆形在内的多种形式,体现了模型的可退化性及通用性.然后,开展了杭州地区饱和软黏土的应力路径三轴不排水剪切试验,分析了软黏土的力学特征,并据此研究了模型参数在不同围压下的稳定性;最后,编制隐式积分算法有限元程序,利用杭州地区饱和软黏土和相关文献中饱和高岭土在不同围压下的等压固结不排水三轴试验验证模型的有效性.对比结果表明:模型计算值与实测值吻合良好,说明该模型能够合理预测不同类型饱和软黏土的不排水剪切特性. 展开更多
关键词 饱和软黏土 蛋形屈服面 弹塑性本构模型 不排水三轴试验 有限元程序
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