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Research of Seed Testa Structure and Storage Material of Peanut Germplasm with Different Resistance to A. flavus 被引量:1
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作者 SHAN Shi-hua WANG Hai-xia +3 位作者 LI Chun-juan WAN Shu-bo LIU Hong-tao JIANG Guo-yong 《Agricultural Sciences in China》 CAS CSCD 2006年第6期478-482,共5页
There was an obvious relationship between seed testa structure, storage material and resistance to A. flavus of peanut. Results showed that seed testa of peanut germplasm with high resistance (HR) to A. flavus infec... There was an obvious relationship between seed testa structure, storage material and resistance to A. flavus of peanut. Results showed that seed testa of peanut germplasm with high resistance (HR) to A. flavus infection had thicker wax layer, integrated and tight epidermis layer, regular vascular tissue range. However, the seed testa of peanut germplasm with high sensitivity (HS) to A. flavus had the reverse results, and results of those with medium resistance (MR) to A. flavus lay in between, but changes of testa thickness were not significant among different resistance kinds. Results also showed that some seed storage materials were closely related with resistance potential to A. flavus. It seemed that varieties with higher resistance to A. flavus had higher oleic acid and protein content, lower linoleic acid and fat content. Content of palm acid, total sugar and VE did not show positive relationship with the resistance to A. flavus. 展开更多
关键词 peanut germplasm resistance to A. flavus seed testa structure and storage material
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Photochemical synthesis of bimetallic Au-Ag nanoparticles with “core-shell” type structure by seed mediated catalytic growth 被引量:4
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作者 董守安 唐春 《中国有色金属学会会刊:英文版》 CSCD 2005年第2期310-313,共4页
The colloidal Au core/Ag shell structure composite nanoparticles were synthesized in PEG-acetone solution by photochemical route. The monodispersed Au nanoparticles with average diameter of 3.9 nm were used as growth ... The colloidal Au core/Ag shell structure composite nanoparticles were synthesized in PEG-acetone solution by photochemical route. The monodispersed Au nanoparticles with average diameter of 3.9 nm were used as growth seeds. The optical property of colloids and the sizes of composite nanoparticles were characterized when the molar ratio of Au to Ag ranges from 4∶1 to 1∶4. The results show that a composite nanoparticle structure similar to strawberry shape is formed at the molar ratio of Au to Ag from 4∶1 to 1∶1; the composite nanoparticles consisting of a core of Au and shell of Ag were generated at the 1∶4 molar ratio, having a striking feature of forming (interconnected) network structure. 展开更多
关键词 金-银胶质 光化学合成 核-壳结构 纳米合金材料
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Polycrystalline ZSM-5 Aggregates Induced by Seed and Catalytic Performance in Methanol to Hydrocarbon
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作者 WANG Xuchang JIAO Chuyu +5 位作者 JI Zhuo JIAO Qirui QIN Bo DU Yanze ZHENG Jiajun LI Ruifeng 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第8期945-954,I0010-I0013,共14页
Synthesis of ZSM-5 zeolite typically utilizes small molecule polyamines or quaternary ammonium salts as organic structure guiding agent(OSDA).By contrast,the OSDA-free hydrothermal synthesis system eliminates the use ... Synthesis of ZSM-5 zeolite typically utilizes small molecule polyamines or quaternary ammonium salts as organic structure guiding agent(OSDA).By contrast,the OSDA-free hydrothermal synthesis system eliminates the use of organic templates and the subsequent calcination procedure.This not only reduces the cost of synthesis,but also prevents environmental pollution from the combustion of organic templates,representing an eco-friendly approach.Despite this,literature suggests that even so-called template-free synthesis systems often involve trace amount of organic substances like alcohol.In the present work,a calcined commercial ZSM-5 zeolite was served as seed,with sodium aluminate as aluminum source and silica sol as silicon source,ensuring an entirely template-free synthesis system.Polycrystalline ZSM-5 aggregates consisted of rod-like nanocrystals were successfully prepared in the completely OSDA-free system.Effects of the Si/Al ratio in ZSM-5 seed,dosage and crystallization conditions such as crystallization temperature and crystallization time on ZSM-5 synthesis were investigated.The results show that a highly crystallinity ZSM-5 aggregate consisting of primary nano-sized crystals less than 100 nm is produced from a gel precursor with 5.6%(in mass)seed after hydrothermal treatment for 48 h.Furthermore,the Si/Al ratio in ZSM-5 seed has little effect on the topological structure and pore structure of the synthesized samples.However,the seeds with a low Si/Al ratio facilitate faster crystallization of zeolite and enhance the acidity,especially the strong acid centers,of the catalyst.The catalytic performance of the synthesized polycrystalline ZSM-5 was evaluated during dehydration of methanol and compared with a commercial reference ZSM-5r.The results exhibit that as compared with the reference catalyst,the fabricated sample has a longer catalytic lifetime(16 h vs 8 h)attributed to its hierarchical pores derived from the loosely packed primary nanoparticles.Additionally,the prepared polycrystalline catalyst also exhibits a higher aromatics selectivity(28.1%-29.8%vs 26.5%). 展开更多
关键词 ZSM-5 polycrystalline aggregate crystal seed structure guiding agent
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Deletion of a 1,049 bp sequence from the 5′UTR upstream of the SiHEC3 gene induces a seed non-shattering mutation in sesame
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作者 Ming Ju Guiting Li +9 位作者 Qiuzhen Tian Hengchun Cao Qin Ma Yinghui Duan Hui Guo Zhanyou Zhang Yingying Huang Huili Wang Haiyang Zhang Hongmei Miao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2589-2604,共16页
Sesame is a labor intensive crop with limited mechanized harvesting mainly due to the seed shattering(SS)trait.In this study,we performed a genetic analysis of the seed-shattering resistance(SR)trait with a SR sesame ... Sesame is a labor intensive crop with limited mechanized harvesting mainly due to the seed shattering(SS)trait.In this study,we performed a genetic analysis of the seed-shattering resistance(SR)trait with a SR sesame mutant 12M07.Unlike the SS type,the parenchyma cells in the abscission zone of the 12M07 mutant are arranged loosely but adhere to the seed coat.Inheritance analysis of six generations derived from 12M07(SR)×Xiangcheng Dazibai(SS)showed that the SR trait is recessive and controlled by a single gene pair.Association mapping of the F2population with 888,619 variants(single-nucleotide polymorphisms(SNPs)and insertion-deletion(InDels))and 31,884 structural variations(SVs)determined that only SV12002 in the 5′upstream region of gene Sindi0765000(named SiHEC3)in Chr.3 was significantly associated with the SR trait.SiHEC3 encodes the bHLH transcription factor.A 1,049 bp deletion occurred in the 5′UTR of Sihec3 in 12M07.SiHEC3 is mainly expressed in developing placental tissues,with the expression peaking in capsules at 45 days after pollination.A dual-luciferase reporter assay in tobacco confirmed that the promoter activity of Sihec3 was reduced because of the deletion of the 1,049 bp promoter sequence.Protein–protein interaction network analysis showed that HEC3 is co-expressed with nine key proteins,such as SHATTERPROOF1(SHP1)and SEEDSTICK(STK)which participate in the secondary wall biosynthesis of the abscission layer in plants.The findings of this study show the important function of Sihec3corresponding with the SR trait and supply the genetic information for breeding new varieties that are amenable to mechanized harvesting in sesame and other crops. 展开更多
关键词 sesame(Sesamum indicum L.) association mapping seed shattering structure variation bHLH transcription factor
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Physiological traits and anatomic structures of the seed for two short cotton season genotypes(Gossypium hirsutum L.) under water stress
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作者 Maryam KOLAHI Elham FAGHANI +1 位作者 Andrea GOLDSON-BARNABY Borhan SOHRABI 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第1期89-98,共10页
Cotton(Gossypium hirsutum L.) is utilized commercially in the production of textile, clothing, and household goods. Its growth is affected by various environmental conditions such as soil, climate, and water supply. I... Cotton(Gossypium hirsutum L.) is utilized commercially in the production of textile, clothing, and household goods. Its growth is affected by various environmental conditions such as soil, climate, and water supply. Irrigation is one of the most important factors for crop management. This research was designed with the aim of studying the biochemical and anatomical features of two genotypes of cottonseed(Latif and Golestan) in order to determine optimum irrigation. Protein, starch, gossypol gland, total soluble protein, starch content, and the anatomical structure of the cotton seeds were investigated. The data were analyzed using the SAS Software. The results showed that when rainfed, Golestan genotype seeds had a larger number of secretory cavities, soluble protein, and starch compared to Latif seeds. There was also a noticeable difference in the size of the seeds. Cellulosic cell walls and protein particles were also observed in the seed structure under induced water stress conditions. It can therefore be concluded that in response to water shortage, there was a noticeable change in the morphometric, anatomic, and biochemical features of the cottonseeds. It can be concluded that when rainfed, the Golestan genotype of cottonseed has more compatibility than the Latif genotype. In general, the application of different levels of irrigation showed that at moderate levels of irrigation, anatomical features appeared more normal. The observations indicate that at high levels of irrigation, some cells begin to dehisce due to osmotic stress, which results in a lack of accurate formation of tissue structures. The Golestan genotype is therefore the best suited for dryland farming. 展开更多
关键词 anatomic structure cotton seed METABOLITES water stress
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Characterization of the Crystal Structure of Sesame Seed Cake Burned by Nd: YAG Laser
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作者 Muna A. Pn Gawbah Abdelrahman A. Elbadawi +2 位作者 Yousef A. Alsabah Mohammed U. Orsod Ali A. S. Marouf 《Journal of Materials Science and Chemical Engineering》 2018年第4期121-131,共11页
This paper reports obtaining of useful and high-value materials from sesame seed cake (SSC). For this purpose, SSC sample was burned for 30 s using Nd: YAG laser with output power 60 W. The products of this process an... This paper reports obtaining of useful and high-value materials from sesame seed cake (SSC). For this purpose, SSC sample was burned for 30 s using Nd: YAG laser with output power 60 W. The products of this process and non-burned SSC were characterized by X-ray diffractometer (XRD), energy dispersive x-ray (EDX) and Fourier transform infrared (FTIR) so as to investigate its crystal structure and chemical components. XRD results of the SSC before burning process showed amorphous silica, rhombohedral phase of carbon, monoclinic phase of aluminum chloride, the hexagonal phase of moissanite-4H, (yellow, black) and hexagonal phase of graphite-2H, C (black). While the results of the burned SSC sample showed that the burning process using the power of Nd: YAG laser cased in appearing of crystalline hexagonal phase for silica and Carbon Nitride and converting the rhombohedral phase of Carbon into hexagonal phase. FTIR showed a number of absorbance peaks assigned to silica. 展开更多
关键词 Crystal structure FTIR HEXAGONAL Carbon Laser-Based Combustion SESAME seed CAKE SESAME Oil CAKE SILICA XRD
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Study of Viability and Seed Structure of Shallot
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作者 Eddy Triharyanto Djoko Pumomo 《Journal of Agricultural Science and Technology(B)》 2014年第2期121-125,共5页
In Indonesia, shallot cultivation finds difficulties to produce high viability seed. That low viability is caused by the abnormality of seed's structure. Normal shallot seeds have seed structure that consists of: te... In Indonesia, shallot cultivation finds difficulties to produce high viability seed. That low viability is caused by the abnormality of seed's structure. Normal shallot seeds have seed structure that consists of: testa, endosperm, and embryo. Normal embryo has curved shape which it has one cotyledon in endosperm. This research purpose is to find shallot viability and structure that is cultivated in tropic area, especially in Indonesia. This research is a deep observation research about water level, seeds viability and seeds structure monitoring by using microscope. To make a clearance about seeds structure composition, seeds are mixed with tetrazolium salt. Monitoring result shows that seed water level at harvest time is 18%, laid away at one month age is 13%, two months age is 12% and three months age is 10%. Seed viability at harvest until twenty nine days, seed that is germinated around 8%. At two months viability seed laid age until twenty two days is 36.6%. Meanwhile three months age laid viability test is done with germination boost compounding shows that IAA is able to fasten germination. At IAA treatment viability seeds are 17.25% that is followed with GA3 treatment around 13%. Another boosting substance that it's viability is only below 4%. Low viability is also proved by the seed structure. The result shows that mostly, the seeds has abnormal structure. 展开更多
关键词 SHALLOT seed structure viability.
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Synthesis and Characterization of Fluorine-containing Polyacrylate Emulsion with Core-Shell Structure 被引量:29
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作者 肖新颜 刘健飞 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第4期626-630,共5页
A fluorine-containing polyacrylate copolymer emulsion was synthesized by a seed emulsion polymerization method, in which methyl methacrylate (MMA) and butyl acrylate (BA) were used as main monomers and hexafluorob... A fluorine-containing polyacrylate copolymer emulsion was synthesized by a seed emulsion polymerization method, in which methyl methacrylate (MMA) and butyl acrylate (BA) were used as main monomers and hexafluorobutyl methacrylate (HFMA) as fluorine-containing monomer. The structure and properties were characterized by Fourier transform infrared spectrum (FT-IR), transmission electron microscopy (TEM), particle size analysis, X-ray photoelectron spectroscopy (XPS), contact angle (CA), differential scanning calorimetry (DSC) and thermogravimetry (TG) analysis. The FTIR and TEM results showed that HFMA was effectively involved in the emulsion copolymerization, and the formed emulsion particles had a core-shell structure and a narrow particle size distribution. XPS and CA analysis revealed that a gradient concentration of fluorine existed in the depth profile of fluorine-containing emulsion film which was richer in fluorine and more hydrophobic in one side. DSC and TG analysis also showed that a clear core-shell structure existed in the fluorine-containing emulsion particles, and their film showed higher thermal stability than that of fluorine-free emulsion. 展开更多
关键词 fluorine-containing polyacrylate emulsion core-shell structure seed emulsion polymerization
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Abnormal Structure of Embryo Sac in Autotetraploid Rice 被引量:3
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作者 Guo Hai-bin FENG Jiu-huan Lu Yong-gen LIU Xiang-dong 《Rice science》 SCIE 2006年第4期257-264,共8页
The structures of mature embryo sacs in 13 genetic stock lines of autotetraploid rice (Oryza sativa L.), including indica, japonica and javanica, were studied by using the whole-mount stain-clearing laser scanning c... The structures of mature embryo sacs in 13 genetic stock lines of autotetraploid rice (Oryza sativa L.), including indica, japonica and javanica, were studied by using the whole-mount stain-clearing laser scanning confocal microscopy (WCLSM). Among the 13 autotetraploid rice, the majority of ovaries possess normal polygonum-type embryo sacs, while a few ovaries were characterized by abnormal embryo sacs. The abnormalities of embryo sacs could be classified into six categories, i. e. no female germ unit, abnormal polar nuclei, embryo sac degeneration, no egg apparatus, small embryo sac and 'double set' of embryo sacs. The frequency of abnormal embryo sac in japonica (26.6%) was higher than that in indica (19.34%). In addition, the major abnormalities in each autotetraploid line varied, suggesting that the abnormalities may be related to the genotypes of the varieties. 展开更多
关键词 autotetraploid rice structure ANATOMY embryo sac seed setting rate
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Current patterns of plant diversity and phylogenetic structure on the Kunlun Mountains 被引量:5
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作者 Wei-Bo Du Peng Jia Guo-Zhen Du 《Plant Diversity》 SCIE CAS CSCD 2022年第1期30-38,共9页
Large-scale patterns of biodiversity and the underlying mechanisms that regulate these patterns are central topics in biogeography and macroecology.The Qinghai-Tibet Plateau serves as a natural laboratory for studying... Large-scale patterns of biodiversity and the underlying mechanisms that regulate these patterns are central topics in biogeography and macroecology.The Qinghai-Tibet Plateau serves as a natural laboratory for studying these issues.However,most previous studies have focused on the entire Qinghai-Tibet Plateau,leaving independent physical geographic subunits in the region less well understood.We studied the current plant diversity of the Kunlun Mountains,an independent physical geographic subunit located in northwestern China on the northern edge of the Qinghai-Tibet Plateau.We integrated measures of species distribution,geological history,and phylogeography,and analyzed the taxonomic richness,phylogenetic diversity,and community phylogenetic structure of the current plant diversity in the area.The distribution patterns of 1911 seed plants showed that species were distributed mainly in the eastern regions of the Kunlun Mountains.The taxonomic richness,phylogenetic diversity,and genera richness showed that the eastern regions of the Kunlun Mountains should be the priority area of biodiversity conservation,particularly the southeastern regions.The proportion of Chinese endemic species inhabiting the Kunlun Mountains and their floristic similarity may indicate that the current patterns of species diversity were favored via species colonization.The Hengduan Mountains,a biodiversity hotspot,is likely the largest source of species colonization of the Kunlun Mountains after the Quaternary.The net relatedness index indicated that 20 of the 28 communities examined were phylo-genetically dispersed,while the remaining communities were phylogenetically clustered.The nearest taxon index indicated that 27 of the 28 communities were phylogenetically clustered.These results suggest that species colonization and habitat filtering may have contributed to the current plant diversity of the Kunlun Mountains via ecological and evolutionary processes,and habitat filtering may play an important role in this ecological process. 展开更多
关键词 BIODIVERSITY Plant community Kunlun mountains Phylogenetic structure seed plants
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Magnetic properties and structure of Ni_80Fe_20/Ni_48Fe_12Cr_40 bilayer films deposited on SiO_2/Si(100) by electron beam evaporation 被引量:1
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作者 WU Ping GAO Yanqing QIU Hong PAN Liqing TIAN Yue Wang Fengping 《Rare Metals》 SCIE EI CAS CSCD 2007年第2期176-181,共6页
Ni80Fe20/Ni48Fe12Cr40 bilayer films and Ni80Fe20 monolayer films were deposited at room temperature on SiO2/Si(100) substrates by electron beam evaporation. The influence of the thickness of the Ni48Fe12Cr40 underla... Ni80Fe20/Ni48Fe12Cr40 bilayer films and Ni80Fe20 monolayer films were deposited at room temperature on SiO2/Si(100) substrates by electron beam evaporation. The influence of the thickness of the Ni48Fe12Cr40 underlayer on the structure, magnetization, and magnetoresistance of the Ni80Fe20/Ni48Fe12Cr40 bilayer film was investigated. The thickness of the Ni48Fe12Cr40 layer varied from about 1 nm to 18 nm while the Ni80Fe20 layer thickness was fixed at 45 nm. For the as-deposited bilayer films the introducing of the Ni48Fe12Cr40 underlayer promotes both the (111) texture and grain growth in the Ni80Fe20 layer. The Ni48Fe12Cr40 underlayer has no significant influence on the magnetic moment of the Ni80Fe20/Ni48Fe12Cr40 bilayer film. However, the coercivity of the bilayer film changes with the thickness of the Ni48Fe12Cr40 undedayer. The optimum thickness of the Ni48Fe12Cr40 underlayer for improving the anisotropic magnetoresistance effect of the Ni80Fe20/Ni48Fe12Cr40 bilayer film is about 5 nm. With a decrease in temperature from 300 K to 81 K, the anisotropic magnetoresistance ratio of the Ni80Fe20 (45 nm)/Ni48Fe12Cr40 (5 nm) bilayer film increases linearly from 2.1% to 4.8% compared with that of the Ni80Fe20 monolayer film from 1.7% to 4.0%. 展开更多
关键词 Ni80Fe20 films Ni48Fe12Cr4o seed layer structure magnetic properties
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Preparation of Core-shell Structured Particles and Their Nucleation in Polyester:I. Preparation of Monodisperse SiO_2/PS Core-shell Composite Particles
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作者 KeYangchuan WuTianbin WangYi 《Petroleum Science》 SCIE CAS CSCD 2005年第1期70-76,共7页
To enhance the nucleation and crystallization properties of polyester (e.g., polyethylene terephthalate, PET), core-shell structured particles are used to improve these properties by controlling the inorganic di... To enhance the nucleation and crystallization properties of polyester (e.g., polyethylene terephthalate, PET), core-shell structured particles are used to improve these properties by controlling the inorganic dispersion properties in the polymers. In the paper, monodisperse particles of silica/polystyrene (PS) are prepared with both dispersion and emulsion polymerization techniques. The monodisperse silicon dioxide particles are first prepared with the seed growth method and modified by the coupling agents. Silica is properly modified with KH-570, and its size deviation is 3.0% or so. The modified silica then reacts with the mixture of ethanol, water medium, and monomer of styrene under dispersion polymerization. Results show that the dispersion polymerization technique is more suitable for monodisperse core-shell SiO2/PS particles than that of the emulsion. The morphology and molecular structure of the core-shell particles are investigated with the transmission electron microscope (TEM), and fourier transform infra-red spectroscopy (FTIR). The results show that the modified silica particles are successfully encapsulated with polystyrene. The average number of silica particles encapsulated into each polystyrene sphere decreases when the size of silica particles increases from 50 nm to 600 nm, and will approach one when the silica is greater than 380nm in size. The mass ratio for silica/PS particles in emulsion polymerization is 4.7/1, lower than that of 6.8/1 for dispersion polymerization, which is the first reported optimized data for preparing the similar monodisperse composite particles. Thus, the PS shell in the former is thinner than that in the latter. 展开更多
关键词 seed growth dispersion polymerization core-shell structured particles
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Genetic diversity and structure of Drimys brasiliensis in southern Brazil:insights for conservation
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作者 Alexandre Mariot Tiago Montagna Maurício Sedrez dos Reis 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第4期1325-1332,共8页
Population genetics studies are widely recognized for generating useful knowledge for biodiversity conservation.To date,however,little is known about the levels and distribution of genetic diversity of Drymis brasilie... Population genetics studies are widely recognized for generating useful knowledge for biodiversity conservation.To date,however,little is known about the levels and distribution of genetic diversity of Drymis brasiliensis(Miers LC),a tree species from the Atlantic Rainforest.Therefore,in this study,we investigated how genetic diversity is distributed within and among populations of D.brasiliensis from southern Brazil using allozyme markers to genotype reproductive trees(8 populations)and seedlings(3 populations).Furthermore,in two populations,we established two permanent plots(5.1 and 1 ha)to analyze fine-scale genetic structure(FSGS).Studied populations presented low levels of genetic diversity(reproductive=0.085;seedlings=0.054)and high fixation indexes(reproductive=0.396;seedlings=0.231).Genetic divergence among populations was equal to 0.05,which is significant,signaling that few populations can conserve large portions of the species total genetic diversity.FSGS was only detected for one population,when reproductive individuals were separated by less than40 m.Low genetic diversity combined with high fixation indexes clearly signal a risk of losing diversity.Therefore,conservation efforts should be aimed at enhancing gene flow within the studied populations. 展开更多
关键词 Atlantic Rainforest Effective population size Fine-scale genetic structure seed collection
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气吸双行错置式玉米密植精量排种器设计与试验 被引量:3
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作者 王韦韦 宋岚洲 +3 位作者 石文兵 魏德华 陈永新 陈黎卿 《农业机械学报》 EI CAS CSCD 北大核心 2024年第3期53-63,共11页
针对大豆-玉米复合密植播种模式下传统气吸式排种器单行种盘高转速作业导致充种时间短、气流稳定性差,难以实现高速精量密植播种的问题,设计了一种气吸双行错置式玉米密植精量排种器,阐述了排种器结构与工作原理,对其工作过程及关键部... 针对大豆-玉米复合密植播种模式下传统气吸式排种器单行种盘高转速作业导致充种时间短、气流稳定性差,难以实现高速精量密植播种的问题,设计了一种气吸双行错置式玉米密植精量排种器,阐述了排种器结构与工作原理,对其工作过程及关键部件进行理论分析,构建充种和投种环节的种子力学模型,确定排种盘内外环型孔排布、投种轮、气室等关键结构参数,并开展单、双气道内负压分布、型孔内气流场特性分析,基于DEM-CFD耦合方法对排种器的排种过程进行仿真分析,以作业速度、气室结构和负压为试验因素,充种合格指数、重充指数和漏充指数为评价指标,优选出最优气室结构。通过台架试验开展不同气吸式排种器排种性能对比试验。试验结果表明,在作业速度为5~10 km/h的高速密植工况下,气吸双行错置式密植精量排种器排种合格指数均大于88.7%,且作业速度为10 km/h时,相较于常用单圆环气吸式排种器合格指数提高5.5个百分点,漏播指数降低5.6个百分点;田间试验结果表明,在作业速度为5 km/h下,播种合格指数为95.7%,重播指数为1.6%,漏播指数为2.8%。提出的气吸双行错置式玉米密植精量排种器在高速作业时拥有良好的排种性能,能够满足大豆-玉米高速精量密植播种要求。 展开更多
关键词 玉米 双行错置式 气吸式排种器 DEM-CFD 气室结构
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油菜高速机械离心式集排器设计与试验 被引量:1
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作者 廖庆喜 沈文惠 +3 位作者 王磊 霍佳琪 罗湛程 廖宜涛 《农业机械学报》 EI CAS CSCD 北大核心 2024年第7期154-167,共14页
针对传统油菜机械离心式集排器高速作业时供种及投种能力不足,导致排种量与作业速度不匹配、排种性能不稳定等问题,设计了一种被动式供种、“圆孔+渐变孔柱”组合式型孔投种的油菜高速机械离心式集排器。构建了供种、投种过程中的力学模... 针对传统油菜机械离心式集排器高速作业时供种及投种能力不足,导致排种量与作业速度不匹配、排种性能不稳定等问题,设计了一种被动式供种、“圆孔+渐变孔柱”组合式型孔投种的油菜高速机械离心式集排器。构建了供种、投种过程中的力学模型,分析确定了影响排种性能的关键结构参数;利用EDEM离散元仿真开展了供种调节高度对供种速率调节量影响的试验,结果表明当供种调节高度为3~8 mm时,供种速率在64.95~357.54 g/min范围内可调;采用两因素三水平正交试验分析了限种套筒下摆高度及倾角对初始种量、临界转速及环状种层最大高度的影响。通过台架试验确定了较优限种套筒结构参数,结合高速摄影对比了5种型孔结构下动锥体转速与排种量关系,确定最优型孔结构为“圆孔+渐变孔柱”组合式型孔。较优参数组合集排器排种性能验证试验结果表明:当转速为115~205 r/min时,排种速率为60.96~355.76 g/min,油菜各行排量一致性变异系数均低于5.2%,总排量稳定性变异系数均低于1.3%,破损率低于0.5%,满足作业速度6~12 km/h时的排种量要求。田间试验结果表明,当机组作业速度为7.89、11.98 km/h时,油菜各行植株均匀性变异系数低于11%,种植密度为43~58株/m^(2),满足油菜精量播种要求。 展开更多
关键词 油菜 高速机械离心式集排器 型孔结构 离散元仿真
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基于SSR标记的钱塘江中下游三角鲂4个放流苗种群体遗传多样性和遗传结构检测
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作者 张敏莹 方弟安 +4 位作者 周彦锋 匡箴 任泷 郑宇辰 徐东坡 《中国农学通报》 2024年第13期157-164,共8页
为检测钱塘江中下游三角鲂放流苗种群体遗传多样性和遗传结构,采用毛细管电泳基因分型技术,基于9对荧光标记SSR引物对来自4个放流苗种群体的192尾样本进行扩增和基因分型测序。结果表明,各群体单个位点检测到的等位基因数Na均值为(20... 为检测钱塘江中下游三角鲂放流苗种群体遗传多样性和遗传结构,采用毛细管电泳基因分型技术,基于9对荧光标记SSR引物对来自4个放流苗种群体的192尾样本进行扩增和基因分型测序。结果表明,各群体单个位点检测到的等位基因数Na均值为(20±2)~(24±2),有效等位基因数Ne均值为(10.76±1.51)~(13.66±1.33),其中余杭群体等位基因数Na和有效等位基因数Ne最大,建德和桐庐群体的这2项指标大体相当;4个群体Shannon’s信息指数I均值为(2.55±0.13)~(2.83±0.09);4个群体观测杂合度Ho均值为(0.83±0.08)~(0.94±0.03),期望杂合度He均值为(0.88±0.02)~(0.92±0.01),绝大多数位点表现出杂合子过剩;余杭、建德、桐庐、富阳各群体的私有等位基因数依次为54、9、15、17个;4个放流三角鲂苗种群体遗传多样性处于较高水平,部分群体出现了杂合子过剩和等位基因丢失现象。分子方差分析显示,98.7%的遗传变异来自群体内的个体间,1.3%遗传变异来自群体间,4个放流群体间遗传分化指数为0.013~0.017,遗传分化很小(0<FST<0.05)。主坐标分析(PCoA)与群体遗传结构分析结果具有一致性,所有个体被分成2个理论类群,但每个类群都包含4个群体的个体,各类群的个体来源没有明显的差异。本研究检测了三角鲂4个放流苗种群体种质遗传现状,以期将来更好地指导三角鲂的增殖放流。 展开更多
关键词 三角鲂 放流苗种 群体 微卫星 遗传多样性 遗传结构
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嗜热酸性Ⅲ型普鲁兰水解酶协同压热制备莲子抗性淀粉的工艺优化及其功能特性研究
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作者 郭建军 曾静 +1 位作者 王通 袁林 《食品工业科技》 CAS 北大核心 2024年第11期195-204,共10页
本研究以莲子淀粉为原料,采用嗜热酸性Ⅲ型普鲁兰水解酶(TK-PUL)与压热联合制备RS3型抗性淀粉(EHP-LRS3)。通过单因素实验和响应面试验对TK-PUL与压热联合制备EHP-LRS3的工艺参数进行了优化,采用扫描电子显微镜和X-射线衍射对EHP-LRS3... 本研究以莲子淀粉为原料,采用嗜热酸性Ⅲ型普鲁兰水解酶(TK-PUL)与压热联合制备RS3型抗性淀粉(EHP-LRS3)。通过单因素实验和响应面试验对TK-PUL与压热联合制备EHP-LRS3的工艺参数进行了优化,采用扫描电子显微镜和X-射线衍射对EHP-LRS3的形貌、晶体结构进行了观察与分析,并考察了EHP-LRS3对长双歧杆菌的促增殖能力。结果表明,在TK-PUL酶解温度为80℃时制备EHP-LRS3的最佳工艺为:向质量分数为35.32%的莲子淀粉乳(pH5.00)中添加25.00 U/g(莲子淀粉)的TK-PUL,将混合物于80℃处理12.70 h,再将其依次于121℃压热处理10 min、4℃回生处理24 h。在最佳工艺条件下,EHP-LRS3的得率为58.46%。扫描电镜分析显示EHP-LRS3呈不规则的沟壑状结构。X-射线衍射分析表明EHP-LRS3的晶体结构呈现出不同于莲子淀粉A型晶体结构的B型晶体结构。EHP-LRS3对长双歧杆菌的促增殖能力优于压热法制备的RS3型抗性淀粉(HP-LRS3)。本研究采用TK-PUL与压热联合制备得到高得率的RS3型抗性淀粉(EHP-LRS3),并验证了EHP-LRS3对长双歧杆菌的促增殖能力,为莲子淀粉的高值化利用提供了理论依据。 展开更多
关键词 莲子淀粉 RS3 型抗性淀粉 Ⅲ型普鲁兰水解酶 工艺优化 结构特性 长双歧杆菌
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微生物发酵法制备茶籽多肽及其功能活性研究
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作者 张宇 陈胜现 +3 位作者 黎玮 李婷 张钰 赵世光 《安徽化工》 CAS 2024年第2期45-49,54,共6页
采用微生物发酵茶籽制备茶籽多肽,并分析其功能活性及构效关系。结果表明:微生物发酵能提升茶籽原料的蛋白质成分释放及多肽生成,以解淀粉芽孢杆菌为最优发酵菌种,其最佳发酵工艺:接种量1%,发酵温度35℃,茶籽添加量50 g/L,pH 6.0,摇床转... 采用微生物发酵茶籽制备茶籽多肽,并分析其功能活性及构效关系。结果表明:微生物发酵能提升茶籽原料的蛋白质成分释放及多肽生成,以解淀粉芽孢杆菌为最优发酵菌种,其最佳发酵工艺:接种量1%,发酵温度35℃,茶籽添加量50 g/L,pH 6.0,摇床转速120 r/min,发酵时间48 h,该条件下茶籽多肽产量达到6.13 mg/mL。茶籽原料经发酵后,小分子量蛋白比例提升了16.25%;茶籽多肽中的必需氨基酸、疏水性氨基酸及酸性氨基酸比例显著提升,使其抗氧化活性优于茶籽原料。 展开更多
关键词 茶籽多肽 微生物发酵 抗氧化活性 构效关系
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不同方法提取罗勒籽胶的理化性质及其结构特性
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作者 刘树萍 张佳美 +2 位作者 彭秀文 李沛钊 邢珂 《精细化工》 EI CAS CSCD 北大核心 2024年第8期1765-1773,共9页
采用酶法提取罗勒籽胶,通过单因素实验及响应面实验确定了最佳工艺,比较不同提取方法(常规法、微波法、超声法和酶法)对罗勒籽胶的得率、理化性质(凝胶强度、持水力、溶胀性能、颜色)、微观结构、流变特性、活性成分(总黄酮、总酚)及抗... 采用酶法提取罗勒籽胶,通过单因素实验及响应面实验确定了最佳工艺,比较不同提取方法(常规法、微波法、超声法和酶法)对罗勒籽胶的得率、理化性质(凝胶强度、持水力、溶胀性能、颜色)、微观结构、流变特性、活性成分(总黄酮、总酚)及抗氧化性的影响。结果表明,酶法提取罗勒籽胶的最佳工艺为:以果胶酶为提取酶制剂、酶添加量4.1%(以预处理后罗勒籽质量为基准)、酶解时间30 min、酶解温度40℃、pH=5.1。在上述优化条件下,罗勒籽胶得率为12.96%;与其他3种方法相比,酶法提取罗勒籽胶得率最高、持水力最佳;微观结构表明,酶法提取的罗勒籽胶具有网络结构;动态流变温度扫描模式说明,罗勒籽胶是稳定的水胶体,其中,酶法提取的罗勒籽胶最稳定;酶法提取的罗勒籽胶能够最大程度地保留活性成分,1,1-二苯基-2-三硝基苯肼自由基清除率达到20.60%±1.44%,2,2'-联氮双(3-乙基苯并噻唑啉-6-磺酸)二铵盐自由基清除率达到8.70%±0.37%。 展开更多
关键词 罗勒籽胶 酶法提取 工艺优化 理化性质 结构特性 中药现代化技术
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大豆种子硬实突变体M_(zp661)的鉴定和基因定位 被引量:1
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作者 苗龙 舒阔 +5 位作者 胡彦姣 黄茹 何艮华 张文明 王晓波 邱丽娟 《中国农业科学》 CAS CSCD 北大核心 2024年第11期2065-2078,共14页
【目的】硬实是种子物理休眠的表现特征,也是大豆驯化的一个重要性状。硬实性虽然有利于种子在不良环境中生存,但是在生产实践中会严重降低大豆出苗率,同时影响产量和加工品质。采用混合群体分离测序(bulked segregant analysis sequenc... 【目的】硬实是种子物理休眠的表现特征,也是大豆驯化的一个重要性状。硬实性虽然有利于种子在不良环境中生存,但是在生产实践中会严重降低大豆出苗率,同时影响产量和加工品质。采用混合群体分离测序(bulked segregant analysis sequencing,BSA-Seq)解析大豆种子硬实性状的遗传基础及候选基因,为大豆硬实的分子机理研究提供理论依据。【方法】经甲基磺酸乙酯(ethyl methane sulfonate,EMS)诱变大豆中品661种子获得硬实突变体M_(zp661),将其与栽培大豆中黄13(父本)杂交构建重组自交系(recombinant inbred line,RIL)群体,对不同株系的种子进行硬实性、吸水率和种皮解剖结构鉴定。选取RIL群体中硬实型和正常吸胀型2种极端材料分别构建混池,利用BSA-Seq技术检测不同极端材料及亲本基因型,结合欧式距离(euclidean distance,ED)和delta SNP-index、delta InDel-index关联分析方法,开展大豆种子硬实遗传位点的挖掘,进一步利用生物信息学分析、大豆不同组织的转录组数据和基因注释信息挖掘显著关联区域的候选基因。【结果】突变体M_(zp661)后代中,吸胀型种子各部位均具有吸水能力,种子体积随浸水时间延长不断增大,然而,硬实型种子浸水36 h内体积未发生变化,随着浸水时间的持续延长,种皮开始局部出现皱缩,并逐渐向其他部位扩散,子叶恢复吸胀能力。硬实型种子种皮表面光滑且结构紧密、角质层呈规则的网状结构、栅栏层较厚,而吸胀型种子表皮有气孔且结构松散、角质层有微小的裂缝、栅栏层较薄,表明突变体M_(zp661)种子硬实与种皮不透水/气相关;ED和delta SNP-index、delta InDel-index关联分析方法不仅鉴定到已报道种子物理休眠遗传位点qHS1,而且检测到1个一致性关联区域Chr.06:45897227—47746047,该区间共含有189个基因,转录组数据及基因注释挖掘到种子中特异高表达的Glyma.06G275300可能为该关联区域调控大豆种子硬实的关键候选基因。【结论】大豆突变体M_(zp661)种子硬实由种皮不透水/气所致,利用BSA-Seq法鉴定到Glyma.06G275300可能为影响种皮结构的候选基因。 展开更多
关键词 大豆 种子硬实 种皮结构 混合群体分离测序 候选基因
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