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Net energy of grains for dairy goats differed with processing methods and grain types
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作者 Xiaodong Su Lei Zhang +8 位作者 Yiyang Sun Yanbo Wu Jianrong Ren Shengru Wu Xinjian Lei Jun Zhang Dangdang Wang Hao Ren Junhu Yao 《Journal of Animal Science and Biotechnology》 2025年第2期729-740,共12页
Background The diverse types and processing methods of grains intricately influence the sites and digestibility of starch digestion,thereby impacting energy utilization.This study aimed to explore the impact of grain ... Background The diverse types and processing methods of grains intricately influence the sites and digestibility of starch digestion,thereby impacting energy utilization.This study aimed to explore the impact of grain variety and processing methods on the net energy(NE)in dairy goats,analyzing these effects at the level of nutrient digestion and metabolism.Methods Eighteen castrated Guanzhong dairy goats(44.25±3.59 kg BW)were randomly divided into 3 groups,each consisting of 6 replicates.The substitution method was employed to determine the NE values of the dry-rolled corn(DRC),dry-rolled wheat(DRW)or steam-flaked corn(SFC,360 g/L).Briefly,two phases were performed.Throughout the basal phase,all goats were fed the same basal diet.In the substitution phase,30%of the basal diet was replaced with DRC,DRW and SFC,respectively.Results In this study,the NE values of the DRC,DRW and SFC were 7.65,7.54 and 7.44 MJ/kg DM,respectively.Compared to the DRC group,the DRW group showed increased digestibility of starch and crude protein(CP).Similarly,the SFC group exhibited increased organic matter(OM)and starch digestibility and a trend towards higher dry matter(DM)digestibility,reduced fecal OM and starch content.Additionally,fecal volatile fatty acid(VFA)concentrations decreased in goats fed SFC.Correspondingly,digestible energy(DE)in the DRW and SFC groups tended to be higher than in the DRC group.DRW increased total VFA concentration compared to DRC,while SFC increased the proportion of propionate and decreased the acetate-to-propionate ratio in the rumen.Both the DRW and SFC diets elevated serum glucose levels.Furthermore,heat increment(HI)and gaseous energy(Gas E)related to fermentation were significantly higher in the DRW and SFC groups compared to the DRC group.Conclusion Our findings indicated that DRW and SFC increased rumen starch fermentation in goats,thereby improving total tract starch digestion and DE.However,DRW and SFC failed to improve NE value due to increased heat and gas energy production from fermentation.Therefore,excessively refined grains processing in the diet of dairy goats does not effectively improve energy efficiency. 展开更多
关键词 Dairy goats Energy metabolism grain types PROCESSING Starch digestion
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Relationship Between Plant Type and Grain Quality of Japonica Hybrid Rice in Northern China 被引量:4
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作者 HAO Xian-bin MA Xiu-fang +3 位作者 Hu Pei-song ZHANG Zhong-xu SUI Guo-min HUA Ze-tian 《Rice science》 SCIE 2010年第1期43-50,共8页
Plant type and grain quality are two major aspects in rice breeding. Using canonical correlation analysis and canonical redundancy analysis, the relationship between plant type traits and rice grain quality traits was... Plant type and grain quality are two major aspects in rice breeding. Using canonical correlation analysis and canonical redundancy analysis, the relationship between plant type traits and rice grain quality traits was studied with 100 crosses derived from 10 sterile lines × 10 restorer lines. There was a complex relationship between parts of the traits of the two aspects. The angle of the 2nd leaf from the top and single panicle weight played important roles in plant type system and amylose content and grain length in grain quality system. The angle of the 2nd leaf from the top, plant height and single panicle weight had a great effect on grain quality traits, and amylose content, brown rice rate and translucency were easily influenced by plant type traits. Selection index model indicated that japonica hybrid rice in Northern China with good quality was characterized by broad flag leaf and 2nd leaf from the top, narrow and short 3rd leaf from the top, low plant height, short culm, long and more panicles and low single panicle weight. 展开更多
关键词 japonica hybrid rice plant type grain quality canonical correlation selection index
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Grain Quality and Genetic Analysis of Hybrids Derived from Different Ecological Types in Japonica Rice (Oryza sativa) 被引量:2
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作者 LENGYan HONGDe-lin 《Rice science》 SCIE 2004年第4期165-170,共6页
The performance and inheritance of 7 quality traits were studied using F2 rice grain derived from 8×8 diallel crossing made by employing 8 parents of different ecological japonica rice types. Differences in each ... The performance and inheritance of 7 quality traits were studied using F2 rice grain derived from 8×8 diallel crossing made by employing 8 parents of different ecological japonica rice types. Differences in each trait among 8 parents were not obvious, but in F2 generation, transgressive phenomena were found in all the traits studied, indicating that the genes controlling these traits among parents were segregated. The inheritance of grain width, grain weight, chalkiness score (CS), gelatinization temperature (GT) and gel consistency (GC) were suitable to additive-dominant model, and dominant effect contributed mainly for the 5 traits. The inheritance of grain length (GL) and amylose content (AC) did not fit into additive-dominant model, existing epistatic interactions. Dominant genes for grain width and grain weight had the efficiency of decreasing effect, and dominant genes for CS, GT and GC had the efficiency of enhancing effect. Koshihikari contained more recessive genes for gelatinization temperature than other varieties. Zhendao 88 had more dominant genes in grain width and grain weight than other varieties. Xiushui 04 possessed more dominant genes for GL and GC, and more recessive genes for CS than other varieties. 展开更多
关键词 hybrid rice grain quality INHERITANCE ecological type
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Comparisons of Protein Composition of Grains at Different Positions in Panicles between Erect and Curved Panicle Type Japonica Rice
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作者 Shuqiang CHEN Jingfang XUE +7 位作者 Xiaodong DU Limin YANG Haixin ZHAO Tong ZHOU Lili SHAN Cui WANG Min LI Guojun PAN 《Agricultural Biotechnology》 CAS 2015年第6期1-6,9,共7页
Under field conditions, three erect panicle type japonica dee cultivars and three curved panicle type japonica rice cultivars were applied as experimental materials to investigate the differences of protein compositio... Under field conditions, three erect panicle type japonica dee cultivars and three curved panicle type japonica rice cultivars were applied as experimental materials to investigate the differences of protein composition of grains at different positions in panicles between two different panicle types of japonica rice. Accord- ing to the results, the panicle type of japonica rice had no direct correlation with albumin content, globulin content, prolamin content and glutelin content in rice, variations of protein composition of grains at different positions in panicles. There were certain correlations between soluble protein contents at different grain posi- tions in the same panicle and the flowering order of glumous flowers in the panicle. Albumin content, prolamin content and glutelin content in grains on secondary rachis branches of two panicle types (erect and curved) of japonica rice cuhivars were higher than that on primary rachis branches, while globulin content exhibited an opposite trend. Globulin content, prolamin content and glutelin content in grains at different positions demonstrated a descending order of bottom 〉 middle 〉 top, while albumin content exhibited an opposite trend. The interactions between primary and secondary rachis branches and among top, middle and bottom rachis branches significantly affected soluble protein contents. 展开更多
关键词 Japonica rice Panicle type grain position Protein composition
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Study on the Relationship of the Characteristics of Vascular Bundles in the First Internode and Grain-filling of Heavy Panicle Type Hybrid Rice 被引量:1
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作者 MA Jun, ZHOU Kai-da, MA Wen-bo, WANG Xue-dong, MING Dong-feng and YAN Zi-bing(Rice Research Institute of Sichuan Agricultural University, Wenjiang 611130, P. R . China) 《Agricultural Sciences in China》 CAS CSCD 2002年第6期631-635,共5页
The characteristics of vascular bundle in the first internode from top and grain-filling of heavy panicle type hybrid rice(HPTHR) were studied. The results were as follows: The HPTHR had more vascular bundles and a mu... The characteristics of vascular bundle in the first internode from top and grain-filling of heavy panicle type hybrid rice(HPTHR) were studied. The results were as follows: The HPTHR had more vascular bundles and a much bigger area of single vascular bundle, all vascular bundle, all phloem and all xylem in the first inter-node than Shanyou63. The vascular bundles had the similar load of spikelet number and sink capacity between the HPTHR and Shanyou63. The HPTHR had not only a larger sink but also normal grain-filling and sink-filling, high seed-setting rate and heavier panicle. Those characteristics of vascular bundle were the biological bases for the larger and heavier panicle of HPTHR. The results also indicated that the breeding model of HPTHR was an effective measure for the super high-yielding rice breeding. 展开更多
关键词 Heavy panicle type hybrid rice First internode Vascular bundle grain-FILLING
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基于多向扫描策略的嵌套命名实体识别模型
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作者 汪梦成 郝晓丽 雷鸣 《计算机工程与设计》 北大核心 2026年第2期503-510,共8页
为解决现有基于跨度的方法捕捉跨度间逻辑顺序和上下文信息不全面的问题,建立了一种基于多向扫描策略的嵌套命名实体识别模型。该模型通过多向扫描策略沿不同方向全面捕捉具有顺序关系的跨度特征,以便更加精确地表征跨度之间的内在联系... 为解决现有基于跨度的方法捕捉跨度间逻辑顺序和上下文信息不全面的问题,建立了一种基于多向扫描策略的嵌套命名实体识别模型。该模型通过多向扫描策略沿不同方向全面捕捉具有顺序关系的跨度特征,以便更加精确地表征跨度之间的内在联系。同时,该模型还引入了序列特征提取模块,用于捕捉距离当前跨度较远的其它跨度特征,进一步丰富了当前跨度的上下文信息。实验结果显示,相较于经典模型,该模型在特征提取方面有较大的提升。 展开更多
关键词 深度学习 自然语言处理 嵌套实体 信息抽取 实体多分类 实体词识别 预训练语言模型
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Drought Types and Impacts on Food Yield and Drought Resistant Countermeasures in Chaoyang
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作者 周广学 李普庆 周晓东 《Meteorological and Environmental Research》 CAS 2010年第7期75-77,81,共4页
The natural precipitation status in Chaoyang District was discussed from aspects of regional distribution,seasonal and annual variation.According to rainfall and evaporation data in recent 50 years from several typica... The natural precipitation status in Chaoyang District was discussed from aspects of regional distribution,seasonal and annual variation.According to rainfall and evaporation data in recent 50 years from several typical stations in Chaoyang,the drought status was analyzed.The drought in each season of Chaoyang was divided into different types,and by using decomposition principle and the scientific simulation method,the main crops' yield in recent 50 years in 5 counties of Chaoyang and precipitation anomaly from April to September was analyzed to find out the main weather restricting factors.Meanwhile,according to the basic principles of farmland water balance and multi-disciplinary theoretical knowledge,some countermeasures were put forward,such as improving eco-environment,culturing drought resistant varieties and adjusting crop layout,so as to improve the utilization of natural precipitation in Chaoyang District,fully tap the water resources,and fight for the full harvest of agricultural production. 展开更多
关键词 Drought type grain yield Drought response China
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有机肥配施氮肥对大粒香籽粒灌浆特性与穗型指数及产量的影响
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作者 雷月 宫彦龙 +1 位作者 唐会会 朱速松 《贵州农业科学》 2026年第2期61-70,共10页
【目的】探明有机肥与氮肥配施对大粒香籽粒灌浆特性、穗型指数和产量的影响,为生产大粒香减氮增效和优化栽培措施提供参考。【方法】以大粒香为试验材料,设置6个处理,分别为不施肥(对照,CK)、单施氮肥(N)、有机肥替代30%氮肥(NF_(1))... 【目的】探明有机肥与氮肥配施对大粒香籽粒灌浆特性、穗型指数和产量的影响,为生产大粒香减氮增效和优化栽培措施提供参考。【方法】以大粒香为试验材料,设置6个处理,分别为不施肥(对照,CK)、单施氮肥(N)、有机肥替代30%氮肥(NF_(1))、有机肥替代50%氮肥(NF_(2))、有机肥替代70%氮肥(NF_(3))和100%有机肥(F),测定不同比例有机肥配施氮肥处理的大粒香强势粒、弱势粒灌浆参数及穗型指数。【结果】与CK相比,随有机肥施用量增加,强势粒、弱势粒灌浆速率最大时的米粒重(Wmax)、籽粒最大灌浆速率(Gmax)、平均灌浆速率(Gmean)和活跃灌浆期(D)均整体呈先增大后减小趋势,到达最大灌浆速率的时间(Tmax)则呈先降低后增高趋势。NF_(1)处理大粒香强势粒的Wmax、Gmax、Gmean和D值均最大,分别为17.6307 mg/grain、1.7221 mg/(grain•d)、1.0892 mg/(grain•d)和26.52 d;Tmax分别比CK、N、NF_(2)、NF_(3)和F处理短1.61 d、0.04 d、0.07 d、1.35 d和0.91 d。NF_(1)处理大粒香弱势粒的Wmax、Gmax、Gmean和D值均最大,分别为12.6819 mg/grain、0.5622 mg/(grain•d)、0.3232 mg/(grain•d)和58.69 d;Tmax分别比CK、N、NF_(2)、NF_(3)和F处理短2.00 d、0.31 d、0.45 d、1.08 d和1.36 d。此外,有机肥配施氮肥明显影响大粒香的穗型指数,随有机肥用量增加呈先升后降趋势,NF_(1)处理显著高于其他处理,为0.53;产量呈下降趋势,NF_(1)处理产量最高,为530.09 kg/667m^(2)。每穗总粒数、有效穗数、结实率、穗型指数和强势粒Wmax为有机肥配施氮肥处理后综合评价产量性状的关键指标。产量与每穗总粒数、有效穗数、穗型指数和强势粒Wmax间呈显著正相关。【结论】合理配施有机肥与氮肥能显著提升大粒香产量,有机肥替代30%氮肥处理产量最高(530.09 kg/667m^(2)),主要通过增加每穗总粒数、有效穗数及穗型指数来提升产量。 展开更多
关键词 大粒香 有机肥 氮肥 灌浆特性 穗型指数
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四川白酒糟在肉牛养殖中的应用探析
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作者 刘超 万玉军 +8 位作者 周树峰 伍文丹 唐玮琦 梁卓 李万均 姚明久 王建文 李洪泉 程明军 《食品与发酵科技》 2026年第1期107-112,共6页
我国肉牛产业面临消费需求激增与养殖成本攀升的双重压力,亟须开发新型饲料资源。该文系统解析了四川白酒糟产量特征与饲用潜力,重点探究不同形态白酒糟(鲜酒糟、干酒糟、发酵酒糟)的营养特征及在肉牛养殖中的适配机制,旨在构建“香型-... 我国肉牛产业面临消费需求激增与养殖成本攀升的双重压力,亟须开发新型饲料资源。该文系统解析了四川白酒糟产量特征与饲用潜力,重点探究不同形态白酒糟(鲜酒糟、干酒糟、发酵酒糟)的营养特征及在肉牛养殖中的适配机制,旨在构建“香型-工艺-饲效”精准匹配技术体系,为缓解饲料短缺、发展节粮型畜牧业提供理论支撑与实践路径。未来需聚焦营养价值评定体系建立和菌种优化,建立“香型-工艺-饲效”精准适配体系,为节粮型畜牧业提供技术支撑。 展开更多
关键词 白酒糟 发酵工艺 肉牛养殖 饲料利用 香型差异
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“三型合醅蒸馏”操作法在复合香型唐山高粱酒中的应用研究
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作者 钱国友 《酿酒科技》 2026年第1期90-96,共7页
以微型窖池为发酵容器,以冀酿2号糯高粱为原料,分型发酵生产小曲清香酒醅(XQ)、浓香双轮酒醅(ND)及酱香第六轮次酒醅(JS)。利用XQ“酒多香少”、ND和JS“香多酒少”的显著特征在“合醅蒸馏”中产生的互补效应,酿造复合香型唐山高粱酒。... 以微型窖池为发酵容器,以冀酿2号糯高粱为原料,分型发酵生产小曲清香酒醅(XQ)、浓香双轮酒醅(ND)及酱香第六轮次酒醅(JS)。利用XQ“酒多香少”、ND和JS“香多酒少”的显著特征在“合醅蒸馏”中产生的互补效应,酿造复合香型唐山高粱酒。将三者分别置于同一甑桶的下、中、上不同甑位区,按不同比例上甑蒸馏。实验得出,XQ、ND、JS的最佳“甑位(_(ZW))区”分别为X_(ZW)∈[3.5,0]、N_(ZW)∈[5.5,3.5]、J_(ZW)∈[10,5.5],由此酿造的52%vol复合香型唐山高粱酒理化及卫生指标:酒精度52.4%vol、固形物0.09 g/L、总酸2.16 g/L、总酯4.25 g/L、己酸乙酯0.27 g/L、甲醇0.22 g/L(100%vol乙醇);酒体感官:无色透明,酱香明显,浓香、窖香、清香及焦香诸香协调舒适,酒体纯净,柔和协调,具有较好的丰满度和持久度,是复合香型唐山高粱酒的代表性产品。 展开更多
关键词 三型合醅蒸馏 复合香型 唐山高粱酒 微型窖池 冀酿2号糯高粱 应用研究
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A Study of Grain Growth Kinetics in Sintered NdFeB Magnets 被引量:1
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作者 刘湘涟 何建平 +1 位作者 董清飞 周寿增 《Journal of Rare Earths》 SCIE EI CAS CSCD 2001年第3期209-213,共5页
The Nd2Fe14 B grain growth kinetics in sintered NdFeB magnets with nominal compositions of Nd30+xDy1.5Fe67.08-xAl0.4B1.02 (%, x = 0, 3) was studied. The grain size parameters were determined by means of the linear int... The Nd2Fe14 B grain growth kinetics in sintered NdFeB magnets with nominal compositions of Nd30+xDy1.5Fe67.08-xAl0.4B1.02 (%, x = 0, 3) was studied. The grain size parameters were determined by means of the linear intercept method on SEM secondary electron images. It is observed that the grain growth process is more sensitive to sintering temperature than to sintering time although the grain size rises with both sintering temperature and time. It is also found that magnets prepared from the pre-alloy powder with a higher oxygen content exhibit a lower grain growth rate and magnets made from the pre-alloy powder with a broader particle size distribution demonstrate a higher grain growth rate. It is believed that the presence of appropriate amounts of Nd oxides effectively impedes the grain growth process and a larger difference in sizes between pre-alloy powder particles significantly accelerates the grain growth process. On the basis of experimental results, the grain growth exponent and the corresponding activation energy were obtained. A possible grain growth mechanism in NdFeB magnets during sintering was briefly discussed. 展开更多
关键词 rare earths NdFeB-type magnet SINTERING grain growth kinetics
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Determination of Optimum Seed Rate of Hybrid Rice (Oryza sativa L.) Varieties in Mat-Type Seedling Raising for Mechanical Transplanting
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作者 Md. Anwar Hossen Md. Kamruzzaman +3 位作者 Sharmin Islam Haimonti Paul Md. Mahir Shahriyar Arafat Ullah Khan 《Agricultural Sciences》 CAS 2022年第10期1031-1047,共17页
Rice is the most important and crucial to ensuring food and dietary energy security in most developing countries and is the staple food of more than half of the world’s population. This study was conducted to identif... Rice is the most important and crucial to ensuring food and dietary energy security in most developing countries and is the staple food of more than half of the world’s population. This study was conducted to identify the seed rate of hybrid rice varieties for mechanical transplanting during Boro (irrigated dry season), 2021-22 season at BRRI research field, Gazipur. Slender grain type BRRI hybrid dhan3, BRRI hybrid dhan5, Ishpahani hybrid dhan6, and BRRI dhan89 were used in the study. The same growth medium was used to establish mat-type seedlings on plastic trays (280 × 80 × 25 mm) at seed rates of 80, 90, 100, 110, and 120 g&#8729;tray<sup>&#8722;1</sup>. Walk-behind type 04 rows rice transplanter (Daedong, model-DP 488) was used during transplanting in the field at the set of the plant to plant spacing of 140 mm while line-to-line spacing was fixed to 300 mm. The result depicted that regardless of the variety, seedling density increased linearly as seed rate increased, except for the 21 days following sowing. However, the seedling density of BRRI dhan89 decreased after the seed rate of 100 g&#8729;tray<sup>&#8722;1</sup> due to mortality. The seedling height of the BRRI hybrids dhan5 and Ishpahani hybrid dhan6 was significantly higher than that of the BRRI hybrid dhan3 and BRRI dhan89. After 21 days, the seedling height decreased significantly with the increase in seed rate. For the seed rates of 100, 110, and 120 g&#8729;tray<sup>&#8722;1</sup>, identical numbers of hills per unit area and plants per hill were observed. On the other hand, regardless of the variety, the percentage of missing hills considerably decreased with the increased seed rate. The yield of the BRRI hybrid dhan5 variety was significantly higher at the seed rates of 100 and 110 g&#8729;tray<sup>&#8722;1</sup>, although the yield of the Ishpahani hybrid dhan6 variety was comparable. In terms of yield among the four varieties, BRRI hybrid dhan5 gave a higher yield followed by Ishpahani hybrid dhan6 while BRRI dhan89 gave a lower yield compared to the hybrid varieties irrespective of the seed rate. However, a seed rate of 110 g&#8729;tray<sup>&#8722;1</sup> gave a significantly higher yield followed by 120 g&#8729;tray<sup>&#8722;1</sup> while 80 and 90 g&#8729;tray<sup>&#8722;1</sup> gave lower grain yield. Generally, mat type seedling of inbred rice varieties is used in Bangladesh. The determination of seed rate of hybrid rice varieties may be increased by the use of rice transplanter in mechanical transplanting of hybrid rice varieties reducing the seed loss and increasing the grain yield. 展开更多
关键词 Slender type grain Seedling Density Seedling Height Missing Hill Plants Per Hill Yield
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Low loss Z-type Hexaferrites with Bi2O3 Additives for Ultra-high Frequency Antenna Applications
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作者 GUO Yongqiang NIE Yan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第5期1037-1042,共6页
The Z-type ferrites of nominal composition Ba3Co2 Fe24O41+x wt% Bi2O3, where x=0.25, 0.5, 1.0, 1.5, 2.0, were prepared by conventional ceramic processes. The influence of Bi2O3 content on the bulk densities, microstru... The Z-type ferrites of nominal composition Ba3Co2 Fe24O41+x wt% Bi2O3, where x=0.25, 0.5, 1.0, 1.5, 2.0, were prepared by conventional ceramic processes. The influence of Bi2O3 content on the bulk densities, microstructures, magnetic and dielectric properties of Z-type ferrite samples were systematically examined so as to obtain materials with low magnetic and dielectric loss tangent over a frequency ranging from 600 to 800 MHz. The experimental results showed that addition of Bi2O3 lowered the sintering temperature(1 020 ℃) and then reduced the average grain size(<2 μm) and enhanced the resistivity(>2.68×10^8 Ω·cm) dramatically, which consequently decreased the magnetic and dielectric loss. Additionally, the low loss factors were observed at the Bi2O3 content x = 1.0, i e, tan δμ/μ’=0.013 and tan δε/ε’= 0.001 at 800 MHz, and such materials could be used for antennas miniaturization from 600 to 800 MHz. 展开更多
关键词 low LOSS Z-type ferrites grain size ANTENNAS
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Accumulation of mercury in rice grain and cabbage grown on representative Chinese soils
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作者 Chun-fa LIU Cheng-xian WU +8 位作者 Muhammad T.RAFIQ Rukhsanda AZIZ Dan-di HOU Zhe-li DING Zi-wen LIN Lin-jun LOU Yuan-yuan FENG Ting-qiang LI Xiao-e YANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第12期1144-1151,共8页
A pot culture experiment was carried out to investigate the accumulation properties of mercury(Hg) in rice grain and cabbage grown in seven soil types(Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambos... A pot culture experiment was carried out to investigate the accumulation properties of mercury(Hg) in rice grain and cabbage grown in seven soil types(Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols) spiked with different concentrations of Hg(CK, 0.25, 0.50, 1.00, 2.00, and 4.00 mg/kg). The results of this study showed that Hg accumulation of plants was significantly affected by soil types. Hg concentration in both rice grain and cabbage increased with soil Hg concentrations, but this increase differed among the seven soils. The stepwise multiple regression analysis showed that pH, Mn(II), particle size distribution, and cation exchange capacity have a close relationship with Hg accumulation in plants, which suggested that physicochemical characteristics of soils can affect the Hg accumulation in rice grain and cabbage. Critical Hg concentrations in seven soils were identified for rice grain and cabbage based on the maximum safe level for daily intake of Hg, dietary habits of the population, and Hg accumulation in plants grown in different soil types. Soil Hg limits for rice grain in Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols were 1.10, 2.00, 2.60, 2.78, 1.53, 0.63, and 2.17 mg/kg, respectively, and critical soil Hg levels for cabbage are 0.27, 1.35, 1.80, 1.70, 0.69, 1.68, and 2.60 mg/kg, respectively. 展开更多
关键词 Mercury accumulation Soil safety Soil types Rice grain CABBAGE INTAKE
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超细磨协同氧化预处理强化类卡林型金矿浸出试验研究
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作者 郑玄 鹿峰宾 +4 位作者 秦香伟 宁霄峰 李新亮 石晓亮 殷传印 《黄金》 2026年第3期55-59,共5页
针对某类卡林型金矿中金嵌布粒度微细(<5μm)、包裹率高(67.11%),且砷(0.40%)以毒砂形式存在而导致的极难浸出问题,开展了系统的工艺矿物学表征与浸出试验研究。结果表明,在磨矿细度−0.074 mm占比90%的常规氰化工艺下,金浸出率仅为32... 针对某类卡林型金矿中金嵌布粒度微细(<5μm)、包裹率高(67.11%),且砷(0.40%)以毒砂形式存在而导致的极难浸出问题,开展了系统的工艺矿物学表征与浸出试验研究。结果表明,在磨矿细度−0.074 mm占比90%的常规氰化工艺下,金浸出率仅为32.14%,属于极难浸出矿石。为改善金矿物解离不充分及硫化矿物干扰问题,提出了“超细磨—氧化预处理—氰化浸出”联合工艺。该工艺通过超细磨将矿石细度提高至−0.010 mm占比80%,并结合纯氧气进行氧化预处理以分解硫化矿物。在溶解氧质量浓度为25 mg/L、氧化时间12 h的条件下,硫化矿物氧化率达60.24%。经预处理后开展氰化浸出试验,金浸出率由常规工艺的35.32%显著提升至64.29%。该工艺对微细粒包裹型难处理金矿资源的开发利用具有借鉴意义。 展开更多
关键词 类卡林型金矿 超细磨 预处理 工艺矿物学 微细粒金 包裹金
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Effect of martensitic transformation on nano/ultrafine-grained structure in 304 austenitic stainless steel 被引量:1
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作者 Na Gong Hui-bin Wu +3 位作者 Gang Niu Jia-ming Cao Da Zhang Tana 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2017年第12期1231-1237,共7页
304 austenitic stainless steel was cold rolled in the range of 20%-80%reductions and then annealed at 700-900°C for 60 sto obtain nano/ultrafine-grained(NG/UFG)structure.Transmission electron microscopy,electro... 304 austenitic stainless steel was cold rolled in the range of 20%-80%reductions and then annealed at 700-900°C for 60 sto obtain nano/ultrafine-grained(NG/UFG)structure.Transmission electron microscopy,electron backscatter diffraction and X-ray diffraction were used to characterize the resulting microstructures.The results showed that with the increase of cold reduction,the content of martensite was increased.The steel performed work hardening during cold-working owing to the occurrence of strain induced martensite which nucleated in single shear bands.Further rolling broke up the lath-type martensite into dislocation-cell type martensite because of the formation of slip bands.Samples annealed at 800-960°C for 60 swere of NG/UFG structure with different percentage of nanocrystalline(60-100 nm)and ultrafine(100-500 nm)grains,submicron size(500-1000 nm)grains and micron size(〉1000 nm)grains.The value of the Gibbs free energy exhibited that the reversion mechanism of the reversion process was shear controlled by the annealing temperature.For a certain annealing time during the reversion process,austenite nucleated first on dislocation-cell type martensite and the grains grew up subsequently and eventually to be micrometer/submicrometer grains,while the nucleation of austenite on lath-type martensite occurred later resulting in nanocrystalline/ultrafine grains.The existence of the NG/UFG structure led to a higher strength and toughness during tensile test. 展开更多
关键词 304 austenitic stainless steel Nano/ultrafine-grained structure Reversion mechanism Lath-type martensite Dislocation-cell type martensite Martensitic transformation
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Design and Experimentation of Multi-Rod Grain Sampling Machine
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作者 He Li Weijian Zhao +1 位作者 Ze Liu Qifeng Cao 《Open Journal of Applied Sciences》 2024年第4期809-817,共9页
In order to enhance grain sampling efficiency, in this work a truss type multi-rod grain sampling machine is designed and tested. The sampling machine primarily consists of truss support mechanism, main carriage mecha... In order to enhance grain sampling efficiency, in this work a truss type multi-rod grain sampling machine is designed and tested. The sampling machine primarily consists of truss support mechanism, main carriage mechanism, auxiliary carriage mechanism, sampling rods, and a PLC controller. The movement of the main carriage on the truss, the auxiliary carriage on the main carriage, and the vertical movement of the sampling rods on the auxiliary carriage are controlled through PLC programming. The sampling machine accurately controls the position of the sampling rods, enabling random sampling with six rods to ensure comprehensive and random sampling. Additionally, sampling experiments were conducted, and the results showed that the multi-rod grain sampling machine simultaneously samples with six rods, achieving a sampling frequency of 38 times per hour. The round trip time for the sampling rods is 33 seconds per cycle, and the sampling length direction reaches 18 m. This study provides valuable insights for the design of multi-rod grain sampling machines. 展开更多
关键词 grain Sampling Sampling Efficiency Truss-type Sampling Machine PLC Control
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Functional foods-based diet as a novel dietary approach for management of type 2 diabetes and its complications: A review 被引量:19
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作者 Parvin Mirmiran Zahra Bahadoran Fereidoun Azizi 《World Journal of Diabetes》 SCIE CAS 2014年第3期267-281,共15页
Type 2 diabetes is a complicated metabolic disorder with both short- and long-term undesirable complications. In recent years, there has been growing evidence that functional foods and their bioactive compounds, due t... Type 2 diabetes is a complicated metabolic disorder with both short- and long-term undesirable complications. In recent years, there has been growing evidence that functional foods and their bioactive compounds, due to their biological properties, may be used as complementary treatment for type 2 diabetes mellitus. In this review, we have highlighted various functional foods as missing part of medical nutrition therapy in diabetic patients. Several in vitro, animal models and some human studies, have demonstrated that functional foods and nutraceuticals may improve postprandial hyperglycemia and adipose tissue metabolism modulatecarbohydrate and lipid metabolism. Functional foods may also improve dyslipidemia and insulin resistance, and attenuate oxidative stress and inflammatory processes and subsequently could prevent the development of long-term diabetes complications including cardiovascular disease, neuropathy, nephropathy and retinopathy. In conclusion available data indicate that a functional foods-based diet may be a novel and comprehensive dietary approach for management of type 2 diabetes. 展开更多
关键词 type 2 diabetes Insulin resistance Functional foods Whole grain Legumes Nuts FRUITS HERBS or SPICES VEGETABLES PREBIOTICS PROBIOTICS
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齐家-古龙凹陷青山口组细粒沉积岩岩相类型、特征及分布规律
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作者 白云风 艾鑫 《大庆石油地质与开发》 北大核心 2025年第4期12-19,共8页
为明确齐家-古龙凹陷青山口组细粒沉积岩的岩相类型、特征及分布规律,基于岩心精描、薄片鉴定、元素分析等方法,建立了页岩岩相划分原则,深入分析古龙页岩岩相类型、地质特征、空间分布规律。结合古沉积环境研究,探讨齐家-古龙凹陷页岩... 为明确齐家-古龙凹陷青山口组细粒沉积岩的岩相类型、特征及分布规律,基于岩心精描、薄片鉴定、元素分析等方法,建立了页岩岩相划分原则,深入分析古龙页岩岩相类型、地质特征、空间分布规律。结合古沉积环境研究,探讨齐家-古龙凹陷页岩岩相形成的控制因素。结果表明:按照“沉积构造+岩石类型”的分类原则,将齐家-古龙凹陷青山口组页岩岩相划分为薄纹层状页岩相、厚纹层状页岩相、块状粉砂质岩相、块状灰质岩相及块状云质岩相共5类;受古地貌及物源供给的影响,各类岩相呈半环带状分布;从古物源、古地貌、古气候、古盐度、古水深及古氧化还原性等方面分析了松辽盆地青山口组沉积时期古沉积环境,此时松辽盆地为温暖湿润的古气候,促使生物勃发,大规模湖侵形成了陆源输入弱、缺氧、强还原的淡水—微咸水沉积环境,为有机质的富集以及页岩储层的形成提供良好的背景条件。研究成果丰富了松辽盆地成熟页岩油勘探理论,为下步松辽盆地北部的页岩油有利富集区优选、井位部署提供了理论依据。 展开更多
关键词 齐家-古龙凹陷 青山口组 细粒沉积岩 岩相类型 有利岩相 分布规律
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木结构销类连接横纹劈裂承载力试验研究
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作者 冯新 杨欣欣 +1 位作者 聂万龙 陈伯望 《土木工程学报》 北大核心 2025年第12期18-38,共21页
销类连接是现代木结构应用最广泛的连接方式,其木材横纹方向的劈裂破坏难以避免,但横纹方向劈裂承载力计算是我国木结构设计中尚未解决的问题。文章梳理总结已有劈裂承载力计算模型的特性及其相关性;开展5组共计266个木结构钢板螺栓连... 销类连接是现代木结构应用最广泛的连接方式,其木材横纹方向的劈裂破坏难以避免,但横纹方向劈裂承载力计算是我国木结构设计中尚未解决的问题。文章梳理总结已有劈裂承载力计算模型的特性及其相关性;开展5组共计266个木结构钢板螺栓连接试件的横纹劈裂性能试验,研究木构件材料、连接节点几何参数、连接节点数量和位置等因素对横纹劈裂承载力的影响。结果表明,横纹劈裂承载力与木构件材料密度、连接节点几何参数和数量呈正相关,在一定范围内,连接节点距外伸梁外伸端部的距离对横纹劈裂承载力有一定影响。基于5个劈裂承载力计算模型与试验结果的对比分析,证明所筛选的劈裂承载力计算模型均有其局限性;进而提出横纹劈裂承载力计算的修正模型,基于1 648个木结构销类连接横纹劈裂承载力的文献数据,验证修正模型的可靠性和适用性。 展开更多
关键词 木结构 销类连接 横纹方向受力 劈裂承载力 计算模型 适用性
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