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Production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller's grains 被引量:2
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作者 李新社 陆步诗 唐伟 《Journal of Central South University》 SCIE EI CAS 2011年第5期1738-1743,共6页
Abstract: Daqu distiller's grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The singl... Abstract: Daqu distiller's grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1:1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller's grains is possible. The research provides a new idea for the reuse of Daqu distiller's grains and also provides a new way for the development of microbial oils. 展开更多
关键词 Daqu distiller's grains Trichoderma.koningii Trichosporon cutaneum CO-FERMENTATION microbial oils
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Rice Grains from Slightly Saline Field Exhibited Unchanged Starch Physicochemical Properties but Enhanced Nutritional Values
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作者 Supranee SANTANOO Wichian SANGWONGCHAI +4 位作者 Maysaya THITISAKSAKUL Suphatta PHOTHISET Paweena PONGDONTRI Noppawan NOUNJAN Piyada THEERAKULPISUT 《Rice science》 SCIE CSCD 2024年第3期343-360,I0055-I0057,共21页
This study aims to investigate grain quality and nutritional values of rice(Pokkali,a salt-tolerant cultivar;RD73,a new cultivar improved from KDML105 introgressed with Saltol QTL from Pokkali,and KDML105,a moderately... This study aims to investigate grain quality and nutritional values of rice(Pokkali,a salt-tolerant cultivar;RD73,a new cultivar improved from KDML105 introgressed with Saltol QTL from Pokkali,and KDML105,a moderately salt-susceptible cultivar)grown under non-saline(0.04–0.87 dS/m)and slightly saline(1.08–4.83 dS/m)field conditions.The results revealed that salinity caused significant reduction in grain size but significant increments in reducing sugar and total protein contents in the grains.Nevertheless,the amounts of starch in the grains of KDML105 and Pokkali rice genotypes were unaffected by the stress.The starch granule size distribution was also unaffected by salinity.Interestingly,only starch from Pokkali was significantly diminished in amylose content,from 19.18%to 16.99%.Accordingly,parameters relating to starch gelatinization,retrogradation,and pasting properties of KDML105 and RD73 were unaffected by salinity;only Pokkali showed a significant increase in percentage of retrogradation along with a significant reduction in gelatinization enthalpy.In the saline field,total phenolic content and antioxidant capacity in the grains of all rice cultivars tended to increase,particularly in Pokkali.On average,essential element contents in grains from the saline-treated plants showed a 33%,32%,32%,22%,20%,11%,and 10%increase in total P,N,K,Mg,Zn,Fe,and Ca content,respectively.Interestingly,total Fe content exhibited the greatest percentage of increments in KDML105(187%).Taken together,cultivation of rice in the slightly saline field did not alter its eating and cooking qualities,while enhanced some nutritional properties such as proteins,minerals,and secondary metabolites like phenolic compounds. 展开更多
关键词 antioxidant capacity elemental composition GELATINIZATION grain morphology RETROGRADATION rice salt stress starch granule
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Research on Heredity of Coarse Ferrite Grains
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作者 Wangzhan FAN Weimin GUI Youfeng CHEN 《Research and Application of Materials Science》 2024年第1期5-8,共4页
The changes in austenite grain size of the specimens with coarse ferrite grains under different heat treatment process were investigated.The focus was on studying the effect of annealing on refining coarse ferrite gra... The changes in austenite grain size of the specimens with coarse ferrite grains under different heat treatment process were investigated.The focus was on studying the effect of annealing on refining coarse ferrite grains,as well as the influence of the ferrite grain size on the main technical indicators of gas carburizing.The results show that coarse ferrite grains may not necessarily cause the coarse austenite grains,but may result in mixed austenite grains.After annealing treatment,the coarse ferrite grains can be significantly refined and homogenized.Moreover,the coarse ferrite grains have no significant effects on hardnessand intergranular oxidationof gas carburizing. 展开更多
关键词 grain size coarse ferrite grains AUSTENITE gas carburizing
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Understanding of Five Grains for YANG:a way to straighten Asians’dietary structure
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作者 Jing-Chao Ma Cai-Jie Zhang +1 位作者 Wen-Li Zhao Ye Zhao* 《Food and Health》 2024年第3期18-19,共2页
According to the general opinion,grains should occupy the largest amount of human food each day,but this grain-based eating habit does not allow human life to be extended.Grains are high in carbohydrates and five comm... According to the general opinion,grains should occupy the largest amount of human food each day,but this grain-based eating habit does not allow human life to be extended.Grains are high in carbohydrates and five commonly recognized plant hormones,namely auxin,gibberellin,cytokinin,abscisic acid,and ethylene.Through in-depth analysis of ancient books,it was found that five grains for support:support is a restriction,and it means the essence,which means that grains should be eaten less,and it is the essence of the least daily intake.To correctly understand the Chinese dietary concept of"five grains for support"is the basis for improving Asian dietary health and promoting Asian human health. 展开更多
关键词 grains HORMONES Carbohydrates Eating habits
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粮食气味物质的提取、关键组分判别及其在储藏中的应用研究进展
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作者 李慧 洪习文 +1 位作者 王争艳 王艳艳 《食品科学》 EI CAS 北大核心 2025年第1期266-273,共8页
粮食气味物质受粮食种类、储藏条件、储藏时间及是否受有害生物污染等多种因素影响,气味物质种类及含量能够及时反映粮食是否变质或受有害生物危害。首先,本文概述目前常用的粮食气味物质的提取和鉴定技术,总结不同状态粮食气味物质组成... 粮食气味物质受粮食种类、储藏条件、储藏时间及是否受有害生物污染等多种因素影响,气味物质种类及含量能够及时反映粮食是否变质或受有害生物危害。首先,本文概述目前常用的粮食气味物质的提取和鉴定技术,总结不同状态粮食气味物质组成,发现烷烃类、酸类、醛类和醇类等物质赋予粮食特有的气味,而不同的储藏环境和粮食状态下,其气味物质存在较大差异。其次,探讨粮食中特征气味物质的分析方法,梳理粮食关键气味物质可能的代谢途径,归纳水稻和小麦中特征气味物质,其中稻谷中特征气味物质2-乙酰基-1-吡咯啉的生成机制也已得到初步确认。最后,对气味物质在粮食安全储藏领域的应用进行概述,提出深入分析、挖掘粮食气味物质数据,构建新型预测模型以快速、精准检测粮食品质将成为未来粮食气味物质研究领域的重要方向;同时,部分气味物质也被证实对粮仓中有害生物具有防控作用,将成为未来研发新型绿色储粮药剂的重要来源。 展开更多
关键词 粮食 气味物质 判别方法 代谢途径 安全储藏
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有机肥替代化肥氮对谷子氮素累积、产量及品质的影响
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作者 王媛 许佳茵 +4 位作者 董二伟 王劲松 刘秋霞 黄晓磊 焦晓燕 《作物学报》 CAS 北大核心 2025年第1期149-160,共12页
有机肥部分替代化肥是一种实现化肥减量的可持续农业生产措施。本研究于2020和2021连续2年以“沁黄2号”为供试材料,设不施氮(CK)、常量化肥氮(NPK)、有机肥替代25%化肥氮(25%M)、有机肥替代50%化肥氮(50%M)、有机肥替代75%化肥氮(75%M... 有机肥部分替代化肥是一种实现化肥减量的可持续农业生产措施。本研究于2020和2021连续2年以“沁黄2号”为供试材料,设不施氮(CK)、常量化肥氮(NPK)、有机肥替代25%化肥氮(25%M)、有机肥替代50%化肥氮(50%M)、有机肥替代75%化肥氮(75%M)和有机肥替代100%化肥氮(100%M) 6个处理,研究不同替代率对谷子产量构成和氮素吸收的影响,并分析氮素吸收调控小米米色、糊化特性和类胡萝卜素组分的效应,明确谷子生产中有机肥最佳替代率。结果表明,2年中较低的有机肥替代化肥氮率显著提高了谷子植株氮素累积,但随着替代率的持续增加,植株氮素累积量呈降低趋势,最终影响谷子产量和小米品质。2020年, 25%M处理显著提高了谷子地上部氮素累积量,较NPK处理提高9.6%;2021年,25%M处理谷子地上部氮素累积量、生物量、穗粒数和产量达到最高,较NPK处理分别提高6.1%、12.0%、15.4%和12.0%。50%M处理显著影响了小米的米色、糊化特征和类胡萝卜素含量,与NPK相比,小米籽粒红绿值、橘色值、支链淀粉含量、总淀粉含量、小米糊化最终黏度、叶黄素含量、玉米黄质含量和黄色素含量的增幅分别可达6.0%、6.0%、7.4%、4.3%、7.8%、20.7%、17.4%和2.8%。但有机肥完全替代化肥降低了谷子地上部氮素吸收、地上部生物量、穗粒数及谷子产量,也抑制了小米叶黄素和玉米黄质含量的提升。2年均表现出谷子地上部氮吸收量与小米单粒重、直链淀粉含量和小米糊化回升值呈显著的负相关。且2021年谷子地上部氮吸收量还与小米总淀粉含量、蛋白质含量、小米粉糊化峰值黏度和小米黄色素含量呈显著的负相关,与小米糊化峰谷黏度呈显著的正相关。综上,施氮总量120 kg hm^(–2)下,有机肥替代25%~50%化肥氮能通过促进植株氮素的吸收,实现产量、米色、蒸煮特性及类胡萝卜素的协同提升,为谷子化肥减量和提质增效生产提供技术支撑。 展开更多
关键词 谷子 有机肥替代化肥氮率 氮素累积 产量 米色 糊化特性 类胡萝卜素
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西北绿洲灌区玉米叶片衰老特征对不同地膜覆盖利用方式的响应
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作者 王丽萍 李盼 +6 位作者 赵连豪 樊志龙 胡发龙 范虹 何蔚 柴强 殷文 《作物学报》 CAS 北大核心 2025年第1期233-246,共14页
西北绿洲灌区玉米传统生产模式中大量使用地膜伴随着生态环境污染严重,且在极端高温下玉米出现叶片早衰。针对该现象,通过免耕一膜2年覆盖利用技术探讨延缓玉米叶片衰老并增加玉米产量的可行性,以期为构建西北绿洲灌区地膜减量玉米高效... 西北绿洲灌区玉米传统生产模式中大量使用地膜伴随着生态环境污染严重,且在极端高温下玉米出现叶片早衰。针对该现象,通过免耕一膜2年覆盖利用技术探讨延缓玉米叶片衰老并增加玉米产量的可行性,以期为构建西北绿洲灌区地膜减量玉米高效生产技术提供理论支撑。2013年在西北绿洲灌区设置免耕一膜2年覆盖利用(NTP)、秋免耕春覆膜(RTP)和传统每年覆新膜(对照, CTP) 3种处理(本文采用2021-2023数据),探究玉米叶片光合源、持绿特性、细胞抗氧化酶活性和渗透调节物质含量对不同地膜覆盖利用方式的响应。结果表明,NTP和RTP可有效调节玉米生育期内光合源和叶片持绿性能的动态关系,维持生育后期较大的叶面积指数(LAI)、光合势(LAD)、叶片持绿性(SG)和叶绿素相对含量(SPAD),有利于延缓叶片衰老。与CTP相比, NTP玉米出苗后75~120 d的LAI、LAD、SG和SPAD分别提高15.1%~16.1%、14.8%~15.5%、7.2%~9.2%和11.3%~11.7%,RTP分别提高12.4%~13.0%、11.5%~12.4%、10.0%~17.6%和6.0%~6.7%。同时,通过单株绿色叶面积的拟合,发现NTP和RTP较CTP叶片衰老时间平均推迟了5.8~7.0d和6.2~7.7d,这可能是由于NTP和RTP有助于增强玉米大喇叭口期-灌浆期叶片的抗氧化能力和细胞渗透调节作用。玉米出苗后60~105 d, NTP较CTP叶片抗氧化酶(SOD、POD、CAT和APX)活性分别提高17.6%~20.0%、28.4%~34.4%、6.7%~8.4%和8.3%~10.9%, RTP较CTP分别提高11.3%~11.7%、16.9%~18.2%、4.4%~6.1%和5.8%~7.7%。此外,与CTP相比,NTP与RTP可溶性蛋白和脯氨酸含量分别提高35.9%~43.9%和29.5%~31.8%,20.7%~31.7%和17.4%~20.4%,丙二醛含量分别降低26.0%~27.8%和17.5%~25.9%。NTP对抗氧化酶和渗透调节物质的影响更大,NTP较CTP增产5.2%~6.0%。免耕一膜2年覆盖利用技术是西北灌区在实现资源减投条件下,有效延缓玉米叶片衰老且增加产量的适宜措施。 展开更多
关键词 地膜覆盖 光合源 抗氧化酶活性 细胞渗透调节能力 籽粒产量
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东北三省粮食生产影响因素的关联分析
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作者 于晓秋 王玉倩 +1 位作者 吴紫薇 齐文莉 《农机化研究》 北大核心 2025年第2期254-261,共8页
东北三省是我国重要的粮食生产基地,研究东北三省粮食生产的主要影响因素具有重要的意义。为此,基于2007—2021年东北三省的面板数据,运用灰色关联理论对影响东北三省粮食生产的影响因素进行关联分析,量化粮食总产量与主要影响因素的关... 东北三省是我国重要的粮食生产基地,研究东北三省粮食生产的主要影响因素具有重要的意义。为此,基于2007—2021年东北三省的面板数据,运用灰色关联理论对影响东北三省粮食生产的影响因素进行关联分析,量化粮食总产量与主要影响因素的关联度。同时,从土地利用水平、农业现代化水平、经济条件3个方面选取8个指标进行关联分析,研究东北三省粮食生产的主要影响因素。结果显示:不同省份粮食生产的主要影响因素不同,土地利用水平和农业现代化水平对东北三省粮食生产影响较大。最后,为东北三省提高粮食产量提供了政策建议。 展开更多
关键词 粮食生产 影响因素 关联分析 东北三省
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基于双目立体视觉的多分辨率图像匹配方法研究
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作者 刘华春 吴广文 闫静莉 《现代电子技术》 北大核心 2025年第1期29-32,共4页
在双目立体视觉系统中,面对复杂场景时噪声会损害图像特征,增加提取难度,导致匹配精度和鲁棒性下降。因此,文中提出基于双目立体视觉的多分辨率图像匹配方法,旨在从不同尺度图像中有效获取信息并实现高精度匹配。该方法利用双目立体视... 在双目立体视觉系统中,面对复杂场景时噪声会损害图像特征,增加提取难度,导致匹配精度和鲁棒性下降。因此,文中提出基于双目立体视觉的多分辨率图像匹配方法,旨在从不同尺度图像中有效获取信息并实现高精度匹配。该方法利用双目立体视觉模型的双目旋转相机扫描目标并进行成像,根据内、外空间标定提升双目旋转相机的位置精度,保证目标的多分辨率成像效果;将其输入金字塔立体匹配网络中,通过网络中的类金字塔多空洞卷积操作提取双目图像特征,在此基础上,基于可变卷积增强其纹理特征细节;结合细粒度特征和互注意力机制完成双目图像匹配。测试结果显示,空间标定后,左、右两个相机的成像误差最小值分别为0.6 Pixel和0.4 Pixel;匹配点坐标偏差均值和坐标偏差方差值分别低于0.012和0.011,匹配效果良好。 展开更多
关键词 双目立体视觉 多分辨率 图像匹配 空间标定 双目旋转相机 特征提取 特征增强 细粒度
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Construction of Vectors to Express Foreign Protein within Potato Starch Grains 被引量:11
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作者 李珺 马力通 姚新灵 《Agricultural Science & Technology》 CAS 2009年第4期72-74,共3页
[Objective] The aim is to study the construction of vectors expressing foreign protein in potato starch grains specifically, and provide some reference for solving industrialized core problem of high cost and low expr... [Objective] The aim is to study the construction of vectors expressing foreign protein in potato starch grains specifically, and provide some reference for solving industrialized core problem of high cost and low expression level of foreign protein. [Method] By using molecular biological techniques of RT-PCR and nested PCR, plant expression vector for the foreign protein locating in the potato starch grains was constructed. [ Result] Coding sequence ( GC20 ) of potato starch grains that was located and expressed by GBSSI promoter was cloned. Plant expression vector was screened out through connection, transformation and enzyme digestion identification. [ Conclusion] This result laid a foundation for further screening the foreign protein on the potato starch grains. 展开更多
关键词 Foreign protein Plant bioreactor GBSSI GC20 Starch grains
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Phase-field simulation of forced flow effect on random preferred growth direction of multiple grains 被引量:1
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作者 王军伟 朱昌盛 +2 位作者 王智平 冯力 肖荣振 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1620-1626,共7页
The random distribution problem of dendrite preferred growth direction was settled by random grid method.This method was used to study the influence of forced laminar flow effect on multiple grains during solidificati... The random distribution problem of dendrite preferred growth direction was settled by random grid method.This method was used to study the influence of forced laminar flow effect on multiple grains during solidification.Taking high pure succinonitrile (SCN) undercooled melt as an example,the forced laminar flow effect on multiple grains was studied by phase-field model of single grain which coupled with flow equations at non-isothermal condition.The simulation results show that the random grid method can reasonably settle the problem of random distribution and is more effective.When the solid fraction is relatively low,melt particles flow around the downstream side of dendrite,and the flow velocity between two dendrite arms becomes high.At the stage of solidification time less than 1800Δt,every dendrite grows freely;the upstream dendrites are stronger than the downstream ones.The higher the melt flow rate,the higher the solid fraction.However,when the solid fraction is relatively high,the dendrite arm intertwins and only a little residual melt which is not encapsulated can flow;the solid fraction will gradually tend to equal to solid fraction of melt without flow. 展开更多
关键词 phase-field method multiple grains laminar flow preferred growth direction computer simulation SOLIDIFICATION flow velocity
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Research on Pollen Grains of Tetraploid Lines and Diploid Control Line of Chrysanthemum cinerariifolium (Trev.) Vis. 被引量:1
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作者 刘蓁 高山林 《Agricultural Science & Technology》 CAS 2010年第5期151-154,共4页
[Objective] The aim was to study characters of pollen grains of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium (Trev.) Vis.,morphological characters,fertility of pollen grain and germinatio... [Objective] The aim was to study characters of pollen grains of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium (Trev.) Vis.,morphological characters,fertility of pollen grain and germination percentage of seeds. [Method] Pollen grains were prepared by sulphuric acid-acetyl oxide decomposition method. The lengths of polar axis and equatorial axis of pollen grains were determined with general optical microscope. The morphology of pollen grains was observed with SEM (scanning electron microscope) and the typical visual fields of 2 500× (or 2 000×),7 000× were taken pictures. [Result] Comparing with the diploid control line,the pollen grains of five tetraploid lines which were tested were different from the diploid line in morphology,sculpture,etc.. 4 of the 5 tested samples were significant larger than the diploid line in size and one was similar to the diploid line. [Conclusion] This research provided references for breeding tetraploid improved varieties of Chrysanthemum cinerariifolium (Trev.) Vis. with good fertility and high germination percentage. 展开更多
关键词 Chrysanthemum cinerariifolium (Trey.) Vis. Tetraploid Pollen grains Fertility
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黑粒小麦花青素抑菌性及其对冷却猪肉保鲜效果
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作者 夏清 智慧 +3 位作者 郭楠 张何静 刘伟佳 杨珍平 《肉类研究》 北大核心 2025年第1期51-57,共7页
为研究黑粒小麦花青素的抑菌性及其对冷却猪肉的保鲜作用,考察黑粒小麦籽粒花青素对大肠杆菌、金黄色葡萄球菌和枯草芽孢杆菌的抑菌能力、最小抑菌质量浓度及其与对羟基苯甲酸乙酯、山梨酸单独和混合使用的抑菌效果;测定黑粒小麦花青素... 为研究黑粒小麦花青素的抑菌性及其对冷却猪肉的保鲜作用,考察黑粒小麦籽粒花青素对大肠杆菌、金黄色葡萄球菌和枯草芽孢杆菌的抑菌能力、最小抑菌质量浓度及其与对羟基苯甲酸乙酯、山梨酸单独和混合使用的抑菌效果;测定黑粒小麦花青素对冷却猪肉色差值、持水力、pH值、硫代巴比妥酸反应物(thiobarbituric acid reactive substances,TBARS)值、总挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量、产H2S能力和菌落总数的影响。结果表明:黑粒小麦花青素对不同细菌表现出独特的抑制效果,效果强弱依次为金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌;其最小抑菌质量浓度分别为1.25、5、10 mg/mL。随着贮藏时间的延长,无菌蒸馏水、40 mg/mL花青素、40 mg/mL花青素+5 μg/mL山梨酸、5 μg/mL山梨酸4种处理下的猪肉亮度值、红度值和持水力均显著降低(P<0.05),其中花青素+山梨酸组色泽最好,持水力最大。冷却猪肉pH值、TBARS值、TVB-N含量和菌落总数则随着贮藏时间延长而增加,保鲜处理组显著低于对照组(P<0.05)。H2S实验中,冷却猪肉随贮藏时间延长表现出阳性,保鲜处理组呈阳性的时间迟于对照组。保鲜能力依次为花青素+山梨酸>山梨酸>花青素>蒸馏水。综上所述,黑粒小麦花青素具有一定的抑菌和保鲜效果,但效果略差于山梨酸,与其混合使用效果最佳。 展开更多
关键词 黑粒小麦 花青素 抑菌性 冷却肉 保鲜
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Ultrastructural Observation of Changes of Polysaccharide Grains in Dormant Shoots of Eucommia ulmoides 被引量:4
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作者 崔克明 罗立新 李正理 《Acta Botanica Sinica》 CSCD 2000年第8期788-793,共6页
Cytochemical and ultrastructural studies indicated that compound spherical bodies observed near the sieve plate in the sieve tube members during the period of cambial dormancy in the shoots of Eucommia ulmoides O... Cytochemical and ultrastructural studies indicated that compound spherical bodies observed near the sieve plate in the sieve tube members during the period of cambial dormancy in the shoots of Eucommia ulmoides Oliv. were polysaccharide bodies different from the polysaccharide grains in other parenchyma cells in shoots, and were similar to cell walls in their staining properties. The compound spherical bodies occurred in the sieve elements during the period of cambial rest and disappeared in the sieve elements during the period of cambial quiescence and activity. 展开更多
关键词 ULTRASTRUCTURE polysaccharide grains sieve tube member DORMANCY Eucommia ulmoides
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基于视觉传达设计的农机操作界面优化研究
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作者 魏亚敏 《农机化研究》 北大核心 2025年第1期199-204,共6页
近年来,随着农业机械智能化的不断发展与应用,农户对农业机械操控功能性、便捷性、易学性和人机交互的良好体验等提出了更高的要求;但是,目前市场上各类农业机械APP界面出现大量“雷同化”特点,难以满足不同农业机械的田间使用要求。为... 近年来,随着农业机械智能化的不断发展与应用,农户对农业机械操控功能性、便捷性、易学性和人机交互的良好体验等提出了更高的要求;但是,目前市场上各类农业机械APP界面出现大量“雷同化”特点,难以满足不同农业机械的田间使用要求。为此,将“人机交互行为”作为设计目标,基于视觉传达技术,以谷物联合收获机操作界面为研究对象开展相关设计。同时,对谷物联合收获机操作界面图形、文字、色彩和设计风格进行分析,结果表明:优化后的农机操作界面能够显著提高操作员的操作效率和工作体验,降低操作错误率和疲劳程度。研究结果可为农业机械智能化操作界面的设计提供可参考的过程设计模型。 展开更多
关键词 操作界面 视觉信息 交互 谷物联合收获机
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基于光电对射阵列下谷物收获流量控制系统的设计
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作者 刘成林 郑世界 《农机化研究》 北大核心 2025年第1期142-147,共6页
在谷物收获过程中,由于谷物的性质不同及收获机械的工作状态不同,谷物的流量往往会出现波动或过大过小的情况,直接影响谷物的收获效率和质量,甚至会导致收获机械的故障。因此,对谷物的流量进行准确的控制和调节是非常重要的。为此,设计... 在谷物收获过程中,由于谷物的性质不同及收获机械的工作状态不同,谷物的流量往往会出现波动或过大过小的情况,直接影响谷物的收获效率和质量,甚至会导致收获机械的故障。因此,对谷物的流量进行准确的控制和调节是非常重要的。为此,设计了一种基于光电对射阵列的谷物收获流量控制系统,可通过使用光电对射阵列检测收获机的运动状态和收获物料的流量,进而控制收获机的速度和工作状态,以实现谷物的准确收获和控制流量。试验验证表明:系统具有较高的准确性和稳定性,能够有效地控制谷物的流量,提高收获效率和质量,具有广泛的应用前景。 展开更多
关键词 谷物收获 流量控制 光电对射阵列 传感器 监测
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双粒竖直勺盘式花生精量穴播器节本增效优化设计与应用
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作者 吾斯曼·吾木尔 阿拉法特·买尔旦 +2 位作者 沙塔尔·司马义 克然木·热合木吐力 祖丽皮亚·艾合买提 《农机化研究》 北大核心 2025年第2期114-121,共8页
根据目前新疆地区花生双粒播种需求,针对现有穴播器结构复杂、维修困难及精量穴播合格率低等问题,通过单粒取种、双粒排种的方式,设计了一种双粒竖直勺盘式花生精量穴播器。通过阐述穴播器结构组成及工作原理,清晰阐明了花生从取种到投... 根据目前新疆地区花生双粒播种需求,针对现有穴播器结构复杂、维修困难及精量穴播合格率低等问题,通过单粒取种、双粒排种的方式,设计了一种双粒竖直勺盘式花生精量穴播器。通过阐述穴播器结构组成及工作原理,清晰阐明了花生从取种到投种整个工作过程,同时对穴播器关键部件取种盘和隔板的结构参数进行了设计。为验证穴播器结构尺寸及性能的可靠性,选取转速、取种窝眼宽度、开口角度为试验因素,以双粒率、漏播率、重播率为试验指标,进行三因素三水平正交试验,并运用Design-Expert软件进行试验分析及参数优化等,得出最优排种组合为转速26.04 r/min、取种窝眼宽度8.8 mm、开口角度52.96°。此时双粒率94.68%、漏播率2.85%、重播率2.47%,符合国家标准。 展开更多
关键词 穴播器 花生 勺盘式 双粒
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Changes in Cooking and Nutrition Qualities of Grains at Different Positions in a Rice Panicle under Different Nitrogen Levels 被引量:15
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作者 DONG Ming-hui SANG Da-zhi WANG Peng WANG Xue-ming YANG Jian-chang 《Rice science》 SCIE 2007年第2期141-148,共8页
Cooking and nutrition qualities of grain are two of the most important aspects of rice quality. To understand the difference in cooking and nutrition qualities among the grains at different positions within a rice pan... Cooking and nutrition qualities of grain are two of the most important aspects of rice quality. To understand the difference in cooking and nutrition qualities among the grains at different positions within a rice panicle, the distributions of gel consistency (GC), amylose content (AC) and crude protein content (CPC) of grains in a panicle in association with different nitrogen levels (0, 120 and 240 k c/ha) were investigated by using two rice varieties, Yangdao 6 (indica) and Wuyujing 3 (japonica). In general, the grains at the basal part of a panicle had lower GC and higher AC than those at the upper or middle part of a panicle. The 1^st grain on the secondary branch with earlier flowering exhibited the highest GC, whereas the 2nd grain on the primary branch with later flowering showed the highest AC. For Yangdao 6, CPC in the grains on the primary branches was lower at the middle part of a panicle than at the upper or basal part of a panicle. For Wuyujing 3, there were no significant differences in CPCs in the grains among the upper, middle and basal parts of a panicle. GC in the grains was increased, whereas AC was reduced from zero nitrogen application (ON) to low amount of nitrogen application (LN), and the result was reversed from LN to medium amount of nitrogen application (MN). CPC was increased with the increase in the amount of nitrogen application. 展开更多
关键词 RICE grain position cooking quality nutrition quality NITROGEN
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Changes in Activities of the Key Enzymes Related to Starch Synthesis in Rice Grains During Grain Filling and Their Relationships with the Filling Rate and Cooking Quality 被引量:17
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作者 ZHAOBu-hong ZHANGWen-jie WANGZhi-qin ZHUQin-sen YANGJian-chang 《Agricultural Sciences in China》 CAS CSCD 2005年第1期26-33,共8页
With 10 rice cultivars (lines) as materials, the changes in activities of adenosine diphosphoglucose pyrophosphorylase(ADPGPase), starch synthase (SSase) and starch branching enzyme (Q-enzyme) in the grains during gra... With 10 rice cultivars (lines) as materials, the changes in activities of adenosine diphosphoglucose pyrophosphorylase(ADPGPase), starch synthase (SSase) and starch branching enzyme (Q-enzyme) in the grains during grain filling, and theirrelationships with the filling rate, gel consistency (GC), alkali spreading value (ASV) and amylose content (AC) werestudied. The results showed that changes in activities of ADPGPase, SSase and Q-enzyme exhibited a single peak duringgrain filling, and the time of the activity peaks for the former two enzymes was earlier than that of the maximum grain-fillingrate (Tmax), and the time reaching the peak for Q-enzyme was synchronous with Tmax. The activities at early grain fillingstage, and the mean and maximum activities of each enzyme during grain filling period were positively and significantly orvery significantly correlated with the mean and maximum grain filling rate and starch content (mg grain-1) in the grains.Activities of ADPGPase at all grain filling stages and those of Q-enzyme at the early and mid filling stages were notsignificantly correlated the cooking quality (GC, ASV and AC). SSase activities at the early filling stage were significantlyand negatively correlated with GC and ASV, and positively correlated with AC. Activities of SSase at mid and late grainfilling stages and Q-enzyme at the late filling stage were significantly and positively correlated with GC and ASV, andnegatively correlated with AC. Spraying zeatin or abscisic acid at early grain filling stage could obviously regulate theactivities of ADPGPase, SSase and Q-enzyme in the grains. 展开更多
关键词 RICE ADPGPase Starch synthase Q-enzyme Grain filling rate Cooking quality
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Biochemical Changes Associated with Germinating Rice Grains and Germination Improvement 被引量:16
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作者 Subajiny VELUPPILLAI Ketheeswary NITHYANANTHARAJAH +2 位作者 Seevaratnam VASANTHARUBA Sandrasegarampillai BALAKUMAR Vasanthy ARASARATNAM 《Rice science》 SCIE 2009年第3期240-242,共3页
To determine biochemical changes during the germination of rice grains (Oryza sativa L. subsp, indica var. Mottaikaruppan) and to improve germination rate using gibberellic acid and surfactants [sodium dodecyl sulfa... To determine biochemical changes during the germination of rice grains (Oryza sativa L. subsp, indica var. Mottaikaruppan) and to improve germination rate using gibberellic acid and surfactants [sodium dodecyl sulfate (SDS) (1.0 g/L) and Triton-X-100 (1.0 mL/L)], whole rice grains soaked in distilled water for 12 h at 30℃were germinated in the dark at 30℃ for five days. The highest germination rate (77.1%) was obtained on the 5th day. An increase in the content of reducing sugars from 7.3 to 58.1 mg/g DM (dry matter) was observed from the 1st day of germination. Free amino acids and soluble protein contents increased to 3.69 and 5.29 mg/g DM, respectively on the 5^th day of germination. Total protein content decreased from 100.5 to 91.0 g/kg DM during germination. Increases in amylolytic (1.1 to 190.0 U/g DM) and proteolytic (0 to 0.12 U/g DM) activities were observed during germination. Effects of different concentrations of gibberellic acid on the germination of rice grains were evaluated and 0.1 g/L was found to promote germination. When effects of gibberellic acid (0.1 g/L) and surfactants were evaluated individually and together, higher germination rate was observed in the control experiment (grains germinated in distilled water), whereas giberellic acid and surfactants decreased the germination rate. Therefore, the flour obtained from the grains germinated for four days using distilled water to obtain high content of soluble materials and enzyme activities can be used in preparation of bakery items. 展开更多
关键词 GERMINATION whole rice grains biochemical changes amylase activity protease activity
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