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基于Seed-PCG法的列车-轨道-地基土三维随机振动GPU并行计算方法
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作者 朱志辉 冯杨 +2 位作者 杨啸 李昊 邹有 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第1期302-316,共15页
为了解决列车-轨道-地基土三维有限元模型随机多样本计算效率低的问题,本文提出了一种基于Seed-PCG法的高效并行计算方法。基于有限元法和虚拟激励法建立轨道不平顺激励下的三维列车-轨道-地基土耦合随机振动分析模型;针对车致地基土随... 为了解决列车-轨道-地基土三维有限元模型随机多样本计算效率低的问题,本文提出了一种基于Seed-PCG法的高效并行计算方法。基于有限元法和虚拟激励法建立轨道不平顺激励下的三维列车-轨道-地基土耦合随机振动分析模型;针对车致地基土随机振动分析产生的多右端项线性方程组求解问题,采用Seed-PCG方法进行求解。通过PCG方法求解种子系统得到的Krylov子空间进行投影,以改进其余线性方程组的初始解和对应的初始残量,有效提高了PCG法的收敛速度,最后,在MATLABCUDA混合平台上开发了并行计算程序。数值算例表明:相同计算平台下的该方法相比多点同步算法获得了104.2倍的加速;相比PCG法逐个求解方案减少了18%的迭代次数,获得了1.21倍的加速。 展开更多
关键词 seed-PCG法 多右端项线性方程组 随机振动 GPU并行计算 列车-轨道-地基土耦合模型
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A Method for Detection of Main Metabolites in Aromatic Rice Seeds 被引量:7
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作者 Bo PENG Dongyan KONG +12 位作者 Xiaohua SONG Huilong LI Lulu HE Andong GONG Yanfang SUN Ruihua PANG Lin LIU Jintao LI Qiying ZHOU Yaqin HUANG Bin DUAN Shizhi SONG Hongyu YUAN 《Agricultural Biotechnology》 CAS 2018年第1期112-116,共5页
[ Objective] A method was developed for the analysis of main metabolites in aromatic rice seeds by gas chromatography-mass spectrometry (GC-MS). [ Method] The main metabolites in seeds of 9 different aromatic rice v... [ Objective] A method was developed for the analysis of main metabolites in aromatic rice seeds by gas chromatography-mass spectrometry (GC-MS). [ Method] The main metabolites in seeds of 9 different aromatic rice varieties were compared and analyzed with two methods. Method 1 : the compound was extracted by the mixture of anhydrous ethanol and methylene chloride ( WV = 1:1 ) at 60 ℃ for 3 h in water bath; the extract was isolated and detected by gas chromatography-mass spectrometry using HP-5 capillary column with scan monitoring mode. Method 2: the main metabolites in aromatic rice seeds were detected using headspaee solid phase micro-extraction and gas chromatography mass spectrometry (GC-MS). [ Result ] Fifteen types of common metabolites were found in 9 different aromatic rice varieties. Method 1 was more effective than method 2 in detecting the main metabolites in aromatic rice seeds. [ Conclusion] This study provides an important reference for clarifying the metabolic pathway of main metabolites in aromatic rice and lays the foundation for further rice breeding. 展开更多
关键词 Aromatic flee seed method METABOLITES GC-MS
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Effects of Cultivation Method on Seed Yield and Quality of Bitter Gourd 被引量:1
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作者 Tianzhu ZHANG Caixia LIU +1 位作者 Zhiqiang MI Xueyuan ZHANG 《Asian Agricultural Research》 2020年第1期53-57,61,共6页
This experiment was carried out to study the possibility of producing germinating seeds of bitter gourd(Momordica charamtia L.)in the climatic conditions of Europe.Seeds of Indian cultivar‘Nana’were sown in the gree... This experiment was carried out to study the possibility of producing germinating seeds of bitter gourd(Momordica charamtia L.)in the climatic conditions of Europe.Seeds of Indian cultivar‘Nana’were sown in the greenhouse and produced transplants were planted on the field.The plants were cultivated in the field in 2 ways:tied to the sticks or creeping on the ground.During the vegetation,the ripen fruits with seeds were collected 6 times,and after extracting,they were germinated in the laboratory following the routine ISTA rules.The best transplants of bitter gourd were received within one month from the seeds emerging 51.8%.The transplant of bitter gourd had average height of7 cm,3-4 leaves,out of which the biggest had the width of 5 cm.Such transplants would grow into fruiting plants.When growing bitter gourd for seeds,the earliest fruits were harvested from the plants tied to the sticks.Moreover,the best seeds were harvested from 2/3 of early fruits.For the purpose of seed production,it is recommended to keep only 3-4 fruits per plant and remove other fruits.The produced seeds germinated from 8%to 24%.If the plants were tied to the sticks,their fruits ripened earlier.The used production way and time of harvest of fruits had no effect on the seed germination.The cultivation methods of bitter gourd plants had no effect on the chemical components of fruits. 展开更多
关键词 BITTER gourd seedS EUROPE CULTIVATION method
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Synthesis of Au nanorods in a low pH solution via seed-media method
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作者 马晓 冯晋阳 +3 位作者 游芳芳 马娟 赵修建 王木琴 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期133-137,共5页
The gold (Au) nanorods with various aspect ratios are obtained by a seed-media method in low pH growth solution. Transmission electron microscopy (TEM) and UV-visible spectrophotometry are utilized to characterize... The gold (Au) nanorods with various aspect ratios are obtained by a seed-media method in low pH growth solution. Transmission electron microscopy (TEM) and UV-visible spectrophotometry are utilized to characterize the Au nanorods, and the longitudinal absorption peak positions of Au nanorods show different shifting trends of the growth evolutions in various low pH (1~3) solutions. Other influential factors on the shape of Au nanorod are also systematically studied under low pH reaction condition. The positions of longitudinal peak shift between 600 nm and 900 nm, with the aspect ratios of Au nanorods varying from 2 to 5 both in the simulation and experimental results. The simulation results are in agreement with experimental ones. 展开更多
关键词 Au nanorods seed-media method aspect ratio surface plasmon absorption
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Effects of Planting Methods and Seed Density on Vegetable Yield and Nutrient Composition of <i>Solanum macrocarpon</i>and <i>Solanum scabrum</i>in Southwest Nigeria
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作者 Mary K. Idowu Durodoluwa J. Oyedele +2 位作者 Ojo Kolawole Adekunle Oluwole Olalekan Akinremi Bob Eilers 《Food and Nutrition Sciences》 2014年第13期1185-1195,共11页
Two field studies were carried out using Solanum macrocarpon and Solanum scabrum to investigate the effects of planting methods and seed density required for optimum biomass yield and nutrient content in southwest Nig... Two field studies were carried out using Solanum macrocarpon and Solanum scabrum to investigate the effects of planting methods and seed density required for optimum biomass yield and nutrient content in southwest Nigeria. Two planting methods (drilling and broadcasting), and two seed densities (4 and 8 table spoon full) were investigated as a 2×2×3 factorial experiment in randomized complete block design and replicated three times. Four seed spoons gave 25.78 kg seeds ha-1 for S. macrocarpon and 20.67 kg·seeds·ha-1 for S. scabrum. Significant highest S. macrocarpon shoots (2.75 kg·m-2) and Ca, K, Fe and Zn contents and S. scabrum (2.95 kg·m-2) and Zn content, were obtained with drilling and four spoons of seeds compared with broadcasting and 8 spoons of seeds. This treatment gave average values for N, P, K, Mg, Ca, Na, Fe, Zn, Mn, Cu, Ca/P and Na/K ratio were 2.79%, 0.03%, 3.37%, 1.64%, 0.02%, 300 mg·kg-1, 100 mg·kg-1, 300 mg·kg-1, 8 mg·kg-1, 1.22 and 0.008 for S. macrocarpon and 2.05%, 0.27%, 5.81%, 3.27%, 2.91%, 0.09%, 280 mg·kg-1, 52.99 mg·kg-1, 359.35 mg·kg-1 and 22.42 mg·kg-1, 11.63 and 0.016 for S. scabrum. It was concluded that planting in drilling made weeding, fertilizer application, irrigation and harvesting more effective rather than by broadcasting, and four spoons of seeds per 9 m-2 produced deep green and broader leaves and balanced nutrient contents than eight spoons of seeds. 展开更多
关键词 SOLANUM macrocarpon SOLANUM scabrum PLANTING method seed Density and NUTRIENT Contents
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Technology of Extracting Kiwi Fruit Seed Oil with Ultrasonic-Assisted Enzyme and Response Surface Method 被引量:1
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作者 Zhi Zhang Mengting Pan Dongmin Liu 《Food and Nutrition Sciences》 2016年第9期807-816,共11页
Taken kiwi fruit as raw material, this paper extracted kiwi fruit seed oil with ultrasonic-assisted enzyme, researched the influence of factors such as liquid-to-solid ratio, granularity, type of enzyme, ultrasonic po... Taken kiwi fruit as raw material, this paper extracted kiwi fruit seed oil with ultrasonic-assisted enzyme, researched the influence of factors such as liquid-to-solid ratio, granularity, type of enzyme, ultrasonic power, treating time, enzymolysis temperature, enzymolysis time, pH and enzyme additive on oil extraction, and optimized the extracting technology of kiwi fruit seed oil with response surface method. The result shows that the best technical parameter is: material granularity: 60, liquid-to-solid ratio: 1:10 (g/mL), ultrasonic power: 400 W, treating time: 30 min, enzyme amount: 2.50%, pH: 9.2, enzymolysis temperature: 53&deg;C, enzymolysis time: 2.80 h;and the extracting ratio under such condition is 92.57%. 展开更多
关键词 Kiwi Fruit seed Oil Ultrasonic Wave Aqueous Enzymatic method
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A Rapid Method for Measuring Seed Protein Content in Cowpea (<i>Vigna unguiculata</i>(L.) Walp) 被引量:1
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作者 Yuejin Weng Ainong Shi +5 位作者 Waltram Second Ravelombola Wei Yang Jun Qin Dennis Motes David Octor Moseley Pengyin Chen 《American Journal of Plant Sciences》 2017年第10期2387-2396,共10页
Cowpea (Vigna unguiculata (L.) Walp), a legume crop that is grown in the worldwide, provides beneficial proteins for human consumption and animal feeding. In comparison, Rapid N analyzer as traditional method, has bee... Cowpea (Vigna unguiculata (L.) Walp), a legume crop that is grown in the worldwide, provides beneficial proteins for human consumption and animal feeding. In comparison, Rapid N analyzer as traditional method, has been widely used to measure protein content through the percentage of total nitrogen in the seed’s grounded powder. Near-Infrared Reflectance (NIR) has commonly been used to measure protein content in soybean seeds using whole grain without the need of seed grinding, which makes it possible to obtain fast results at a lower cost-per-analysis than the traditional combustion method. The specific objective of this study is to test a rapid method for measuring cowpea seed protein content by the NIR analyzer comparing to the traditional rapid N analyzer. A total of 240 cowpea genotypes were used in this study, including six seed coat colors, black, blackeye, browneye, cream, pinkeye, and red with 40 cowpea genotypes. The results showed that a linear relationship exists between the NIR analyzer and the Rapid N analyzer in the six different color groups. The correlation efficiency (r) between the seed protein contents from NIR and Rapid N was higher for pinkeye seed (r = 0.867), blackeye (0.771), cream (0.729), browneye (0.700), and red (0.623), respectively, but lower for black seeds, indicating that the NIR analyzer can be used to measure protein content for cowpea seeds with the five types of seed coat except black. Overview, the cowpea seed protein content measured from the NIR analyzer showed a little higher seed protein content. A series of regression models with different seed coat color have been built to adjust to protein content of colorful cowpea seeds from the NIR analyzer. But, it is not recommended to use for black color seeds due to a very low correlation efficiency (r) value with 0.184. 展开更多
关键词 COWPEA seed PROTEIN CONTENT PROTEIN Measurement method Rapid N ANALYZER Near-Infrared Reflectance (NIR) Vigna unguiculata
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交错凸齿式宽苗带小麦精量排种器设计与试验 被引量:1
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作者 张春岭 刘涛 +3 位作者 郑子浩 方俊 谢晓东 陈黎卿 《农业工程学报》 EI CAS CSCD 北大核心 2024年第5期47-59,共13页
针对外槽轮式小麦宽苗带排种器排量不稳定和苗带内种子分布均匀性较差的问题,该研究设计了一种交错凸齿式宽苗带小麦精量排种器。通过连续充种分析和排量计算,确定凸齿高度和凸齿角度是影响排量一致性和排种均匀性的关键参数。应用离散... 针对外槽轮式小麦宽苗带排种器排量不稳定和苗带内种子分布均匀性较差的问题,该研究设计了一种交错凸齿式宽苗带小麦精量排种器。通过连续充种分析和排量计算,确定凸齿高度和凸齿角度是影响排量一致性和排种均匀性的关键参数。应用离散元法对上述关键参数进行中心旋转组合仿真试验,结果表明,对排量一致性、排种均匀性影响显著性程度由大到小的因素分别依次为凸齿角、凸齿高、作业速度,且均具有交互影响。借助响应面分析,得出凸齿高5 mm、凸齿角75°时的排量一致性和排种均匀性较优,平均变异系数分别为2.27%和7.61%。对该参数组合排种器进行样机试制,并进行台架试验,台架试验结果表明,排种一致性和均匀性变异系数与仿真值误差均低于5%,说明仿真优化结果可靠、准确。田间对比试验结果表明,播量120、150和180 kg/hm~2时,交错凸齿式宽苗带小麦精量排种器的播量一致性、纵向播种均匀性和横向播种均匀性变异系数分别较外槽轮式排种器降低0.99、3.01和9.38个百分点,满足小麦宽苗带播种农艺要求。研究结果可为提高排种均匀性的小麦排种装置设计提供参考。 展开更多
关键词 排种器 离散元法 小麦 精量排种 交错凸齿 排量稳定性 排种均匀性
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High Quality DNA Obtained from a Single Seed of <i>Vitis vinifera</i>L. Using Rapid DNA Extraction Method
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作者 Ajith Samantha Rathnayake Josep Allué +3 位作者 Mercè Llugany Anna Puig-Pujol Kshanika Hirimburegama Charlotte Poschenrieder 《American Journal of Plant Sciences》 2014年第13期2023-2030,共8页
Use of a single seed is very useful for genetic studies on Vitis vinifera. However, molecular markers require a fair amount of high purity DNA. Grapevine contains high concentrations of polysaccharides, polyphenols, t... Use of a single seed is very useful for genetic studies on Vitis vinifera. However, molecular markers require a fair amount of high purity DNA. Grapevine contains high concentrations of polysaccharides, polyphenols, tannins and other secondary metabolites. These compounds may hamper the DNA isolation processes and subsequent analysis. In this study we have compared two DNA isolation methods: the NucleoSpin Plant II method and a modified protocol from Doyle and Doyle. The average value of 260/280 nm absorption ratio, which is used to assess the purity of DNA and RNA was 1.8 (accepted as “pure” DNA) and 0.9 (presence of protein or other contaminants) for the first and second method, respectively. Using the NucleoSpin protocol, from a single seed (20 - 35 mg) we obtained an average yield of extracted DNA of 24.8 ± 5.2 to 38.4 ± 11.5 ng·mg-1 dry weight. Among the two protocols examined, the NucleoSpin method was more efficient and gave better quality of DNA values compared to those from the modified Doyle and Doyle procedures. 展开更多
关键词 VITIS Single seed High Quality DNA DNA Extraction method
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直播方式对重庆地区稻田杂草群落组成和生态位的影响
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作者 黄乾龙 王楚桃 +6 位作者 何永歆 欧阳杰 朱子超 管玉圣 蒋刚 熊英 李贤勇 《浙江农业学报》 CSCD 北大核心 2024年第2期383-390,共8页
为高效绿色防除重庆地区直播稻田杂草,对淹水直播和湿润直播处理下稻田杂草的群落组成和生态位进行研究。结果表明,淹水直播和湿润直播稻田的杂草群落分别由16种(隶属于9科15属)和18种(隶属于10科17属)杂草组成,水蓼(Polygonum hydropip... 为高效绿色防除重庆地区直播稻田杂草,对淹水直播和湿润直播处理下稻田杂草的群落组成和生态位进行研究。结果表明,淹水直播和湿润直播稻田的杂草群落分别由16种(隶属于9科15属)和18种(隶属于10科17属)杂草组成,水蓼(Polygonum hydropiper)和鬼针草(Bidens pilosa)为湿润直播下特有的杂草。淹水直播和湿润直播的重要杂草群落结构分别为丁香蓼(Ludwigia prostrata)+鸭舌草(Monochoria vaginalis)+稗草(Echinochloa crus-galli)和陌上菜(Lindernia procumbens)+稗草(E.crus-galli)+看麦娘(Alopecurus aequalis)+异型莎草(Cyperus difformis)。除稗草(E.crus-galli)外,两种直播方式下重要杂草的重要值均差异显著(P<0.05)。两种直播方式共有的14种重要或主要杂草中,淹水直播下光头稗(Echinochloa colonum)、稗草、异型莎草、陌上菜、看麦娘、笄石菖(Juncus prismatocarpus)、双穗雀稗(Paspalum distichum)共7种重要或主要杂草的生态位宽度较湿润直播下显著降低,且其种间(除笄石菖与双穗雀稗外)生态位叠加值或显著降低或持平。综上,淹水直播可抑制水蓼和鬼针草的萌发,从而改变稻田重要杂草的群落结构,而且可控制光头稗、稗草、异型莎草、陌上菜、看麦娘、笄石菖、双穗雀稗的数量。 展开更多
关键词 直播方式 稻田杂草 群落组成 生态位
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晶种法直接水热合成含磷ZSM-5分子筛及其芳构化性能研究
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作者 曹健 郝坤 +5 位作者 邢梦姣 王飞 陶智超 杨勇 相宏伟 李永旺 《低碳化学与化工》 CAS 北大核心 2024年第6期87-94,共8页
费托合成油品向高辛烷值汽油转化的流化床体系中,水蒸气的存在极易导致ZSM-5分子筛发生不可逆的水热失活,而磷的引入能提高ZSM-5分子筛的水热稳定性。采用晶种法在无胺体系下直接水热合成了含磷ZSM-5分子筛(HS-P-Z5),并与常规浸渍法得... 费托合成油品向高辛烷值汽油转化的流化床体系中,水蒸气的存在极易导致ZSM-5分子筛发生不可逆的水热失活,而磷的引入能提高ZSM-5分子筛的水热稳定性。采用晶种法在无胺体系下直接水热合成了含磷ZSM-5分子筛(HS-P-Z5),并与常规浸渍法得到的含磷ZSM-5分子筛(IM-P-Z5)进行了对比。通过XRD、SEM和N2吸/脱附等对水热处理前后的ZSM-5分子筛进行了表征,通过水洗实验考察了磷元素的流失情况,并以1-辛烯为探针分子评价了ZSM-5分子筛的芳构化性能。结果表明,HS-P-Z5比IM-P-Z5具有更高强度的特征衍射峰、更多的微孔结构和酸量。水洗实验和NMR表征结果表明,HS-P-Z5具有更加稳定的磷铝结构,磷物种不易被洗掉,故其具有更好的水热稳定性,在水热处理后能够保留更多分子筛的微孔结构以及强酸位点。HS-P-Z5-ST(ST表示水热处理)具有最高的芳烃选择性,在反应时间730 min时,其芳烃选择性为23.1%,高于IMP-Z5-ST(18.4%)以及Z5-ST(11.2%)。 展开更多
关键词 含磷ZSM-5分子筛 晶种法 芳构化 水热稳定性
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赤霉素不同浓度及处理方式对青藏高原柴达木盆地盐爪爪种子萌发的影响 被引量:1
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作者 拉本 胡娟 +3 位作者 张旭萍 刘强 王锦 胡笑玫 《中国野生植物资源》 CSCD 2024年第5期63-67,76,共6页
目的:探究两种赤霉素处理方式、不同赤霉素浓度对盐爪爪种子萌发指标的影响,旨在得出不同因素对盐爪爪萌发的作用效果,寻求提高盐爪爪萌发的最适条件。方法:采用培养皿纸上萌发法,统计种子萌发情况,计算萌发率、萌发势、萌发指数等指标... 目的:探究两种赤霉素处理方式、不同赤霉素浓度对盐爪爪种子萌发指标的影响,旨在得出不同因素对盐爪爪萌发的作用效果,寻求提高盐爪爪萌发的最适条件。方法:采用培养皿纸上萌发法,统计种子萌发情况,计算萌发率、萌发势、萌发指数等指标。结果:(1)在提前浸种组内,随着赤霉素浓度的增加,盐爪爪种子的萌发率、萌发势、萌发指数3项萌发指标也随之增加,但萌发指标小于对照组;(2)在每日滴加组内,赤霉素浓度的变化对盐爪爪种子的萌发不具有显著影响,萌发指标均高于对照组;(3)赤霉素浓度在200~1000 mg/L之间时,每日滴加的处理方式下盐爪爪种子萌发率在92.22%~98.89%之间,提前浸种组处理方式下盐爪爪种子萌发率在56.67%~80.00%之间,前者显著高于后者。结论:(1)在提前浸种组内,低浓度的赤霉素不具有促进盐爪爪种子萌发的作用;(2)在每日滴加组内,200~1000 mg/L的赤霉素对盐爪爪种子的萌发指标均具有促进作用;(3)赤霉素浓度在200~1000 mg/L之间时,每日滴加的方式更适用于盐爪爪种子的萌发。 展开更多
关键词 赤霉素 处理方式 盐爪爪 种子萌发
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Rapid Determination of Seed Number and Thousand Kernel Weight of Asparagus officinalis L.Using Image Processing Method
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作者 Huimin GAO Yu TIAN +1 位作者 Zhiqiang LIU Yanpo CAO 《Asian Agricultural Research》 2019年第11期53-55,共3页
Asparagus officinalis L.is favored by its high health function,but its hybrid seeds are expensive.The amount of seed,seed plumpness and germination rate are related to the production costs of breeding enterprises and ... Asparagus officinalis L.is favored by its high health function,but its hybrid seeds are expensive.The amount of seed,seed plumpness and germination rate are related to the production costs of breeding enterprises and large growers.Therefore,it is necessary to investigate the seed number and thousand kernel weight of A.officinalis L.This study developed a quick and accurate method to measure the seed number and thousand kernel weight of A.officinalis L.using image processing technology.Seed sample of A.officinalis L.was scanned with 200 dpi resolution,and the seed number was then obtained using Image-ProPlus software.After weighing the seeds,thousand kernel weight was finally calculated.By recording‘macro’,the batch processing of the samples can also be realized.This method is simple and accurate,and can greatly save the time of investigation. 展开更多
关键词 ASPARAGUS OFFICINALIS L. seed number Thousand KERNEL WEIGHT Image processing method
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松籽油水酶法提取及酶法破乳工艺研究
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作者 张根生 李思锦 +3 位作者 田阳 韩冰 谢春丽 费英敏 《浙江农业学报》 CSCD 北大核心 2024年第9期2089-2098,共10页
以压榨松籽饼粕为原料,利用水酶法提取松籽油,通过单因素及响应曲面试验研究松籽油提取工艺,并对提油过程中产生的乳状液进行破乳研究分析。结果表明,碱性蛋白酶酶解效果最佳,最优工艺为酶解时间2.5 h,温度56℃,pH值11.3,加酶量5045 U&#... 以压榨松籽饼粕为原料,利用水酶法提取松籽油,通过单因素及响应曲面试验研究松籽油提取工艺,并对提油过程中产生的乳状液进行破乳研究分析。结果表明,碱性蛋白酶酶解效果最佳,最优工艺为酶解时间2.5 h,温度56℃,pH值11.3,加酶量5045 U·g^(-1),此条件松籽油提油率为71.73%。经比较碱性蛋白酶添加量为3000 U·g^(-1)时破乳效果最好,破乳率为87.68%,在酶法破乳后进行酸化处理,通过调节pH值至5时破乳率提高至92.18%,此条件下松籽油得油率为70.36%。 展开更多
关键词 松籽饼粕 松籽油提取 水酶法 酶法破乳
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石榴籽油的提取、营养组成及健康功效研究进展 被引量:1
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作者 胡子聪 胡超凡 +3 位作者 李彦坡 蒋巧俊 李群和 房翠兰 《中国油料作物学报》 CAS CSCD 北大核心 2024年第1期208-220,共13页
石榴籽油是从石榴加工剩余物石榴籽中提取得到的一种功能性植物油,它具有抗氧化、抗炎症、抗肿瘤和预防心血管疾病等功效。本文从石榴籽油的提取方法、营养组成和健康功效等方面,对近年来国内外有关石榴籽油的研究结果进行了全面综述。... 石榴籽油是从石榴加工剩余物石榴籽中提取得到的一种功能性植物油,它具有抗氧化、抗炎症、抗肿瘤和预防心血管疾病等功效。本文从石榴籽油的提取方法、营养组成和健康功效等方面,对近年来国内外有关石榴籽油的研究结果进行了全面综述。水酶法、溶剂萃取法、超临界流体萃取法和物理场辅助提取法对石榴籽油的得率和脂肪酸组成有明显的影响。尽管源于不同产地和不同提取方法的石榴籽油在脂肪酸组成上存在差异,但整体上来看,石榴籽油中不饱和脂肪酸占比达到88.57%~95.33%,其中以石榴酸为主(60.62%~81.40%),它是石榴籽油能够发挥一系列营养功效的主要活性成分。因此,石榴籽油是一种具有高营养价值和潜在利用价值的木本植物油,本文旨在为石榴籽油的进一步研究及其在食品、生物医药等领域的开发利用提供理论参考。 展开更多
关键词 石榴籽油 提取方法 营养组成 石榴酸 健康功效 活性机制
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基于EDEM的高速穴播器排种性能仿真分析与试验 被引量:1
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作者 卢博 倪向东 +3 位作者 李克志 李树峰 齐庆征 邵文平 《中国农机化学报》 北大核心 2024年第2期48-54,共7页
为探究穴播器转速和种子初速度对穴播器排种性能的影响,对分置式排种系统及穴播器工作原理进行阐述。利用EDEM建立棉种及穴播器的仿真模型,模拟棉种具有不同的初速度及穴播器在不同转速下排种情况,根据运动轨迹曲线、受力变化曲线、速... 为探究穴播器转速和种子初速度对穴播器排种性能的影响,对分置式排种系统及穴播器工作原理进行阐述。利用EDEM建立棉种及穴播器的仿真模型,模拟棉种具有不同的初速度及穴播器在不同转速下排种情况,根据运动轨迹曲线、受力变化曲线、速度变化曲线综合分析产生漏播、重播现象的原因。使用Design-Expert进行两因素五水平二次旋转正交组合试验设计,建立评价指标的回归方程,并通过响应曲面分析排种性能。合格率随穴播器转速的增大而先增加后降低,随种子初速度的增大而降低。优化后的仿真参数组合为穴播器转速39 r/min和种子初速度2.4 m/s,最佳优化结果为漏播率3.2%,合格率95.1%,重播率1.7%。台架验证性试验结果表明仿真试验可信,穴播器排种性能满足高速精量播种要求,为新疆地区棉花机械化高速精量穴播技术及发展提供参考。 展开更多
关键词 棉种 排种性能 穴播器 精量播种 离散元法
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非水溶液体系中晶种法制备球形银纳米颗粒
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作者 王轩禹 王开军 +3 位作者 朱家军 胡劲 段云彪 张维钧 《贵金属》 CAS 北大核心 2024年第1期35-39,共5页
以丙三醇作溶剂,硝酸银为原料,聚乙烯吡咯烷酮(PVP)为分散剂,硼氢化钠为还原剂制备了银纳米晶种;以此银纳米粒子作为初级晶种,以丙三醇作溶剂和还原剂,通过升温提高丙三醇的还原性制备银纳米颗粒。研究分散剂种类、生长液银浓度、晶种... 以丙三醇作溶剂,硝酸银为原料,聚乙烯吡咯烷酮(PVP)为分散剂,硼氢化钠为还原剂制备了银纳米晶种;以此银纳米粒子作为初级晶种,以丙三醇作溶剂和还原剂,通过升温提高丙三醇的还原性制备银纳米颗粒。研究分散剂种类、生长液银浓度、晶种加入量对银粉的影响,采用X射线粉末衍射仪(XRD)、场发射扫描电子显微镜(FE-SEM)、透射电子显微镜(TEM)对制备产物的结构、物相、形貌进行表征。结果表明,通过改变条件可以制备出分散性良好、粒径均匀的70nm左右的球形银粉。 展开更多
关键词 非水溶液体系 晶种法 纳米银粉 粒径 球形
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不同贮藏方式对籽莲种子耐盐碱能力的影响
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作者 王恺聪 文波龙 +4 位作者 徐惠风 任俊 罗那那 路鑫雨 张宇琦 《种子》 北大核心 2024年第9期8-15,共8页
为探究不同贮藏方式对籽莲种子耐盐碱能力的影响,本研究通过模拟控制实验,分析了常温干藏、常温沙藏、低温干藏、低温沙藏和冷冻贮藏共5种不同贮藏方式处理下,籽莲种子的性状变化及幼苗的耐盐碱特征,以期筛选出最优的种子贮藏方式。结... 为探究不同贮藏方式对籽莲种子耐盐碱能力的影响,本研究通过模拟控制实验,分析了常温干藏、常温沙藏、低温干藏、低温沙藏和冷冻贮藏共5种不同贮藏方式处理下,籽莲种子的性状变化及幼苗的耐盐碱特征,以期筛选出最优的种子贮藏方式。结果表明,常温沙藏下的籽莲种子及幼苗在盐碱胁迫下表现出较好的生长状态,其发芽势、发芽率,幼苗的芽长、鲜重及过氧化物酶活性均显著高于其他贮藏方式,而低温贮藏会使籽莲种子处于逆境状态,进而导致幼苗脯氨酸、可溶性糖、超氧化物歧化酶活性增加。 展开更多
关键词 籽莲 种子 贮藏方式 盐碱胁迫
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金哲辨治未破裂卵泡黄素化综合征经验
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作者 贡欣 张晓晓 李树苗 《山东中医杂志》 2024年第9期1015-1019,共5页
总结金哲教授治疗未破裂卵泡黄素化综合征(LUFS)经验。根据B超下卵泡大小,LUFS可分为小卵泡型、卵泡滞留型和卵泡持续增大型,其中卵泡滞留型多合并子宫内膜异位症和多囊卵巢综合征,不同分型的LUFS各有其特点,金教授认为应分型辨证。治疗... 总结金哲教授治疗未破裂卵泡黄素化综合征(LUFS)经验。根据B超下卵泡大小,LUFS可分为小卵泡型、卵泡滞留型和卵泡持续增大型,其中卵泡滞留型多合并子宫内膜异位症和多囊卵巢综合征,不同分型的LUFS各有其特点,金教授认为应分型辨证。治疗上,需总体把握种子调经这一核心思想辨证论治,并根据月经周期的阴阳消长规律进行分期论治。创立“育卵三法”分期论治小卵泡型LUFS;卵泡滞留型LUFS合并子宫内膜异位症者,以化瘀为首,合并多囊卵巢综合征者,以利湿化痰、散瘀调经为主;对于持续增长型LUFS,则以化痰消癥为法,分期治疗。 展开更多
关键词 未破裂卵泡黄素化综合征 种子调经 育卵三法 子宫内膜异位症 多囊卵巢综合征 分期论治 金哲 不孕
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Effects of Salt Stress on Seed Germination and Seedling Growth in Raphanus sativus L. 被引量:1
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作者 梅燚 祖艳侠 +2 位作者 吴永成 郑佳秋 郭军 《Agricultural Science & Technology》 CAS 2013年第8期1112-1116,1159,共6页
[Objective] This study aimed to investigate the effects of salt stress on seed germination and seedling growth in radish(Raphanus sativus L.).[Method] First,effects of soaking seeds with clear water and different co... [Objective] This study aimed to investigate the effects of salt stress on seed germination and seedling growth in radish(Raphanus sativus L.).[Method] First,effects of soaking seeds with clear water and different concentrations of saline solution were compared; then,different concentrations of salt solution (0.2%-1.0%) was used to treat radish during the whole germination period.[Result] soaking seeds with clear water can improve the germination indicators of radish seeds exposed to high salt stress; low salt concentration(0.2%,0.4%) had little effect on the growth indicators of radish seedlings,and 0.2% salt concentration can even promote the growth of radish seedlings,however,the high salinity had a bad inhibition on seedling growth,the higher the salt concentration,the stronger the inhibition.[Conclusion] According to the comprehensive comparison,the order of the six varieties in salt-tolerance was as follows:Xinxiayuanbai>W1029,Xiayuanbai > Nanyangbailizhi,Chunyidianhong> Sijihong 3. 展开更多
关键词 Radish(Raphanus sativus L.) Salt stress seed soaking methods Germination indicators
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