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Thailand Experience in Developing Wellness-driven Rice as the Key to Fight NCDs and Farmer Poverty 认领
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作者 Apichart Vanavichi Siriphat Ruangpayak 《粮油食品科技》 2020年第5期57-63,共7页
Prevalence of chronic noncommunicable diseases(NCDs)is rapidly increasing and has become a global problem in modern day.Over consumption of simple,processed carbohydrate foods is considered one of the main causes of N... Prevalence of chronic noncommunicable diseases(NCDs)is rapidly increasing and has become a global problem in modern day.Over consumption of simple,processed carbohydrate foods is considered one of the main causes of NCD in young and elderly populations.Whole grain rice is an important source of a complex carbohydrate,dietary fiber,enriched with vitamins,minerals,and antioxidants.However,palatability of brown rice is the key success factor among white-rice-addicted communities.In the initial phase,we successfully breed rice strains with aromatic,soft-whole grain,white rice contains high grain-Fe/Zn density and intermediate glycemic index(GI).The most successful variety was uniquely soft-textured black purple rice named Riceberry,depicting rice enriched with blueberry nutritional characteristics.Product development for fiber-rich,high antioxidant has been extremely active from academia,real sectors,and SMEs.In total,39 patent applications(18 granted patents),12 international publications,and 18,700 Youtubes related to Riceberry.From 2017,Riceberry has become the most popular choice for product development surpassing Thai Hommali Rice.More than 200 food and non-food products were commercialized as dairy replacement,side dishes,meals,hot beverages,bakery,and breakfast cereals.In the second phase,we successfully breed low GI rice strains named Pink+4 equipped with farmers’preferred resistance to flash flooding,bacterial leaf blight,leaf blast,and devastating brown planthopper adapted to organic rice production.Innovative products combined of low GI rice flour with purple Riceberry have been the next trend for functional ingredients and foods.These healthy rice products have high potential globally as healthy foods,gluten-free,fiber-rich,complex carbohydrate,and nutrient-dense from sustainable organic farming. 展开更多
关键词 whole-grain rice non-communicable diseases(NCDs) glycemic Index(GI) riceberry Thai Hommali Rice organic farming flash flooding bacterial leaf blight leaf blast brown planthopper gluten-free foods
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Basal internode elongation of rice as affected by light intensity and leaf area 认领
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作者 Xuhua Zhong Kaiming Liang +5 位作者 Bilin Peng Ka Tian Xiaojuan Li Nongrong Huang Yanzhuo Liu Junfeng Pan 《作物学报:英文版》 SCIE CAS CSCD 2020年第1期62-70,共9页
Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of bas... Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of basal internodes persists.The objectives of this study were(1) to identify key factors affecting the elongation of basal internodes and(2) to establish a quantitative relationship between basal internode length and canopy indices.An inbred rice cultivar,Yinjingruanzhan,was grown in two split-plot field experiments with three N rates(0,75,and 150 kg N ha-1 in early season and 0,90,and 180 kg N ha-1 in late season) as main plots,three seedling densities(16.7,75.0,and 187.5 seedlings m-2) as subplots,and three replications in the 2015 early and late seasons in Guangzhou,China.Light intensity at base of canopy(Lb),light quality as determined from red/far-red light ratio(R/FR),light transmission ratio(LTR),leaf area index(LAI),leaf N concentration(NLV) and final length of second internode(counted from soil surface upward)(FIL) were recorded.Higher N rate and seedling density resulted in significantly longer FIL.FIL was negatively correlated with Lb,LTR,and R/FR(P < 0.01) and positively correlated with LAI(P < 0.01),but not correlated with NLV(P > 0.05).Stepwise linear regression analysis showed that FIL was strongly associated with Lband LAI(R2= 0.82).Heavy N application to pot-grown rice at the beginning of first internode elongation did not change FIL.We conclude that FIL is determined mainly by Lband LAI at jointing stage.NLV has no direct effect on the elongation of basal internodes.N application indirectly affects FIL by changing LAI and light conditions in the rice canopy.Reducing LAI and improving canopy light transmission at jointing stage can shorten the basal internodes and increase the lodging resistance of rice. 展开更多
关键词 INTERNODE ELONGATION LEAF area index LIGHT intensity LIGHT quality R/FR Light transmission ratio LEAF N concentration
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Leaf area index estimated by direct, semi-direct, and indirect methods in European beech and sycamore maple stands 认领
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作者 Jakub Cerny Pavel Haninec Radek Pokorny 《林业研究:英文版》 SCIE CAS CSCD 2020年第3期827-836,共10页
Leaf area index(LAI)is one of the most important characteristics of forest stands that affects the fundamentals of tree physiological processes,biomass production,and mechanical stability.The LAI results obtained by t... Leaf area index(LAI)is one of the most important characteristics of forest stands that affects the fundamentals of tree physiological processes,biomass production,and mechanical stability.The LAI results obtained by the semi-direct and indirect methods(the needle technique and an LAI-2000 PCA)in three European beech(Fagus sylvatica L.)stands and one sycamore maple(Acer pseudoplatanus L.)stand were compared with LAI estimated by litter traps during the 2013 growing season.Seasonal LAI was estimated using an LAI-2000 PCA which showed similar trends among the stands and strongly corresponded to phenological phases of deciduous stands in Europe,with the fastest rate of leaf area increment occurring during the first month following bud break.During the growing season,maximum stand LAI value was on June 19th and reached 4.5–5.1,and 4.0 in the beech and maple stands,respectively.The needle technique significantly underestimated(p<0.05)direct LAI on average by 22.0% and 40.0% in the beech and maple stands,respectively.The LAI-2000 PCA insignificantly underestimated(p>05)LAI on average by 15.1%and 5.8%in the beech and maple stands,respectively.All methods for LAI estimation at the stand level could be applicable in deciduous forest stands(beech,maple)with similar site and stand characteristics.However,calibration by direct method is necessary to obtain the required precision. 展开更多
关键词 LEAF area index Specific LEAF area LITTER TRAP Needle technique LAI-2000 PCA
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Structural Features of the Leaf and Fruit of the Emerald Variety <i>Olea europaea</i>L., Growing under the Introduction Conditions of Surkhandarya 认领
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作者 Sodikjon Kh. Abdinazarov Guljan M. Duschanova 《美国植物学期刊(英文)》 2020年第4期554-563,共10页
For the first time, the anatomical structure of the leaf, petiole and fruit of the emerald variety Olea europaea, which grows under the conditions of introduction in the Oltinsay district of the Surkhandarya region of... For the first time, the anatomical structure of the leaf, petiole and fruit of the emerald variety Olea europaea, which grows under the conditions of introduction in the Oltinsay district of the Surkhandarya region of Uzbekistan, was studied. The following characteristic diagnostic features were determined: in the leaf—the dorsiventral type of leaf mesophyll;thick-walled outer walls of the epidermis;slightly sinuous outlines of the cells of the adaxial epidermis, rectilinear-abaxial;hypostomotic leaves;non-submerged stomata of the anomocytic type;thyroid silver-gray and white-fluffy star-shaped squamous-numerous on the adaxial epidermis than on the adaxial;chlorophyll-bearing palisade and spongy parenchyma;closed collateral type of conductive bundles;the most scleralized leaf due to the presence of filamentous scleroids in it (long, thin, resembling fibers);in the petiole—parenchymal-beam type of structure;the location of the angular collenchyma under the epidermis;closed collateral type of conductive bundles;the presence of thick-walled parenchymal cells and the presence of filiformscleroids;pericarp of the fetus consists of a rigid 1-layer exocarp, parenchymal mesocarp, and sclerenchymal endocarp;the presence of scleroids—stony cells and branched sclerenchymal fibers with drops of oil in the parenchymal cells. Diagnostic signs revealed by us reflect xeromorphic of this species. All the signs were compared, and we came to the conclusion that the anatomical signs of the leaf and the fetus can be useful for providing diagnostic signs for distinguishing the studied taxa, can be used in taxonomy, and can serve to identify plant materials. 展开更多
关键词 Anatomy LEAF PETIOLE PERICARP of the Fetus OLEA europaea Surkhandarya Region Uzbekistan
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The Anatomical Structure of Leaves and Thorns Plants <i>Astragalus pterocephalus</i>Bunge, Growing in Uzbekistan 认领
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作者 Manzura A. Agzamova Guljan M. Duschanova +1 位作者 Hasan A. Rakhmatov Abdulaziz A. Janibekov 《美国植物学期刊(英文)》 2020年第4期569-577,共9页
The results of a study conducted by light microscopy of the anatomical structure of the leaf and thorns of Astragalus pterocephalus growing in the natural habitat of the Amankutan Mountains of the Samarkand region (Uz... The results of a study conducted by light microscopy of the anatomical structure of the leaf and thorns of Astragalus pterocephalus growing in the natural habitat of the Amankutan Mountains of the Samarkand region (Uzbekistan) are presented. The following diagnostic features were identified: leaf—isolateral-palisade type of mesophyll leaf;thick-walled outer walls of the epidermis;the outline of epidermal cells is rectilinear, the projection is polygonal;amphystomatic leaves;submerged numerous stomata of hemiparacitic and anomocytic type;chlorophyll-bearing palisade and spongy parenchyma;closed collateral type of vascular bundles and more sclerified, due to sclerenchymal cells. Thorn—parenchymal-beam type of structure;thin-walled outer walls of the epidermis;under the epidermis is a lamellar collenchyma;closed collateral type of vascular bundles and more sclerified, due to sclerenchymal cells. The complex of the above features reflects the species specificity of the structure of the leaf and spines. Identified and described features that can be used in the taxonomy of the studied tribes and can serve to identify plant materials. 展开更多
关键词 ASTRAGALUS pterocephalus Anatomy Leaf THORN Amankutan Mountains SAMARKAND
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Forage Production and Selection for Vigor in Meadow and Hybrid Bromegrass in the Northern Great Plains 认领
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作者 R. Martine Similien Arvid Boe Bruce Coulman 《美国植物学期刊(英文)》 2020年第1期91-110,共20页
Meadow bromegrass (Bromus riparius Rehmann) is an important forage crop in Canada and the Intermountain West, but it has not been extensively evaluated in the northern Great Plains (NGP). Our objectives were to 1) eva... Meadow bromegrass (Bromus riparius Rehmann) is an important forage crop in Canada and the Intermountain West, but it has not been extensively evaluated in the northern Great Plains (NGP). Our objectives were to 1) evaluate meadow, smooth, and hybrid bromegrasses for forage production under intensive management in eastern South Dakota, and 2) evaluate the effect of selection for vigor in multiple environments on forage production of meadow bromegrass. Thirteen populations (7 meadow bromegrass, 5 hybrid bromegrass, and 1 smooth bromegrass) were evaluated for 4 yrs (2005-2007, 2009) at Brookings, SD. Biomass at anthesis was greater for smooth (6.75 Mg ha-1) than for meadow or hybrid brome (5.4 Mg ha-1) in 2005, but production at anthesis during 2006 and 2007 was similar for meadow and smooth bromegrass. Regrowth harvested during July and October 2005 and November 2006 was greater for meadow than smooth or hybrid bromegrass. Forage production at anthesis in 2009, after rest (i.e., no cutting) and fertilization in 2008, was 4.2 Mg ha-1 for meadow bromegrass compared with 3.3 Mg ha-1 and 2.6 Mg ha-1 for hybrid and smooth bromegrass, respectively. Smooth and hybrid bromegrasses had more leaves·tiller-1 than meadow bromegrass. After 6 yrs, meadow bromegrass had higher tiller density and greater potential for tolerating multiple harvests during a growing season than did smooth or hybrid bromegrass. Selection for vigor in multiple environments in North America resulted in experimental populations of meadow bromegrass with superior forage yield compared with ‘Fleet’ on marginal crop land in the northern Great Plains. 展开更多
关键词 BROMUS riparius Smooth BROMEGRASS BROMUS inermis Morphology Phytomer Biomass Partitioning Leaf Ratio TILLER Density Marginal CROPLAND
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Sugar Starvation Enhances Leaf Senescence and Genes Involved in Sugar Signaling Pathways Regulate Early Leaf Senescence in Mutant Rice 认领
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作者 LI Zhaowei ZHAO Qian CHENG Fangmin 《水稻科学:英文版》 SCIE CSCD 2020年第3期201-214,共14页
To clarify the complex regulatory relationship between changes in sugar content and leaf senescence during the grain-filling stage of rice,genotype-dependent differences in sugar content and the temporal transcription... To clarify the complex regulatory relationship between changes in sugar content and leaf senescence during the grain-filling stage of rice,genotype-dependent differences in sugar content and the temporal transcriptional patterns of genes involved in sugar signaling pathways were determined in mutant rice exhibiting early leaf senescence and its wild type Zhefu 142.The effects of exogenous glucose or sucrose on the senescence of detached leaves under dark conditions were also investigated.Chlorophyll,soluble sugar,sucrose and fructose contents decreased,whereas electrolytic leakage and malondialdehyde levels increased in mutant leaves at the grain-filling stage.These results suggested that sugar starvation is positively correlated with the early leaf senescence of mutant plants.Detached leaf segments incubated in exogenous sugar solutions under dark conditions exhibited delayed senescence.The high expression of Hxk1 in leaves of mutant plants at the initial grain-filling stage suggested that Hxk1 is involved in the hexose-sensing process at the early stage of leaf senescence.The low expression levels of Hxk2 and Frk1 in the senescing leaves of mutant rice during the grain-filling stage are indicative of weakened hexose phosphorylation.In addition,the high expression levels of Su Sy1,Su Sy2 and Su Sy4 in leaves of mutant plants at the initial grain-filling stage are accompanied by the high transcript levels of SUT1,which favor sucrose translocation and remobilization from the early senescing leaves of mutant rice.The relatively reduced transcript levels of ch FBP,cy FBP,SPS1,SPS2 and SPS6 indicated that during the grain-filling stage,sucrose biosynthesis is weakened in the senescing leaves of mutant rice. 展开更多
关键词 RICE sugar STARVATION LEAF SENESCENCE signaling pathway DETACHED LEAF segment GRAIN-FILLING stage
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First Report of Phomopsis Leaf Spot on Patchouli [Pogostemon cablin( Blanco) Benth. ]Caused by Diaporthe arecae in China 认领
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作者 Qingqian ZENG Hanqian HUANG +3 位作者 Zhouxi LEI Yicheng HUANG Yong HUANG Huiyun FAN 《农业生物技术:英文版》 CAS 2020年第2期14-15,共2页
A severe leaf spot disease on patchouli,was observed in Guangdong,China.Early symptom appeared as circular or irregularly shaped and dark brown spots along the leaf margins and tips.As the disease progressed,the spots... A severe leaf spot disease on patchouli,was observed in Guangdong,China.Early symptom appeared as circular or irregularly shaped and dark brown spots along the leaf margins and tips.As the disease progressed,the spots enlarged and with masses black,sessile conidiomata were observed in lesions.The results of morphology,molecular biology and pathogenicity test indicate that the causal agent of leaf disease of patchouli is Diaporthe arecae. 展开更多
关键词 Patchouli PHOMOPSIS LEAF SPOT DIAPORTHE arecae
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A new Curvularia lunata variety discovered in Huanghuaihai Region in China 认领
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作者 CHANG Jia-ying LIU Shu-sen +3 位作者 SHI Jie GUO Ning ZHANG Hai-jian CHEN Jie 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第2期551-560,共10页
The purpose of this study was to identify the dominant pathogens of Curvularia leaf spot and their pathogenicity variation in Huanghuaihai Region of China in recent years.In 2013 and 2016–2017,the occurrences of Curv... The purpose of this study was to identify the dominant pathogens of Curvularia leaf spot and their pathogenicity variation in Huanghuaihai Region of China in recent years.In 2013 and 2016–2017,the occurrences of Curvularia leaf spots on maize were investigated in fields located in Henan,Hebei,Shandong,and Anhui provinces,and 292 fungi were isolated from diseased leaves.These fungal isolates were subjected to morphological identification,and 232 isolates were found to have about 70%uncurved conidia and were identified as Curvularia lunata var.Most of the conidia of 2 representative isolates,namely,HNWB-131 and HNWB-185,were oblong with parallel septations and were distinctly different from a reference isolate CX-3.For further determination,the internal transcribed spacer(ITS),glyceraldehyde 3-phosphate dehydrogenase(GPDH),the large subunit(LSU),and translation elongation factor 1-alpha(EF1-α)sequences of HNWB-131,HNWB-185,and CX-3 were amplified and sequenced.The results of sequence analysis showed that the 4 gene sequences from the 3 isolates had a similarity of more than 99%to C.lunata.Based on the sequences of ITS and the combined data of the 4 genes,neighbor-joining trees were constructed for phylogenetic analysis.The results indicated that these 3 isolates were clustered together with C.lunata.The expression of Clg2 p and ClUrase genes in mycelia and conidia was significantly(P<0.05)higher in CX-3 than in HNWB-131 and HNWB-185.This study found that the dominant pathogen of Curvularia leaf spot was a new variety of C.lunata with morphological variations in Huanghuaihai Region from 2013 to 2017.The pathogenicity of the C.lunata var.was not significantly enhanced,and the expression of Clg2 p and ClUrase genes of C.lunata var.was decreased. 展开更多
关键词 CURVULARIA lunata CURVULARIA LEAF SPOT MORPHOLOGICAL identification PHYLOGENETIC analysis
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薄壳山核桃愈伤组织诱导的优化 认领
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作者 郑小琴 谭鹏鹏 +4 位作者 冯刚 曹凡 周樊 彭方仁 李永荣 《分子植物育种》 CAS CSCD 北大核心 2020年第11期3704-3712,共9页
本研究以薄壳山核桃品种苗‘波尼’幼嫩叶片为外植体,设置不同消毒方法、不同蔗糖浓度、不同褐化抑制剂及不同植物生长调节剂浓度及配比,研究其对叶片诱导愈伤组织形成的影响。结果表明,不同消毒方法对薄壳山核桃叶片愈伤组织形成影响显... 本研究以薄壳山核桃品种苗‘波尼’幼嫩叶片为外植体,设置不同消毒方法、不同蔗糖浓度、不同褐化抑制剂及不同植物生长调节剂浓度及配比,研究其对叶片诱导愈伤组织形成的影响。结果表明,不同消毒方法对薄壳山核桃叶片愈伤组织形成影响显著,以0.1%HgCl2消毒2 min效果最好,污染率为15.6%,且愈伤组织生长状态最好;不同蔗糖浓度对叶片愈伤组织形成的影响以30 g/L效果好,愈伤诱导率达75.6%;不同褐化抑制剂对叶片愈伤组织影响较小,其中以0.2 g/L PVP效果最好,不仅褐化率低且愈伤诱导率高;不同植物生长调节剂浓度及配比对薄壳山核桃叶片愈伤组织形成影响显著,以4/5MS+0.75 mg/L TDZ+0.5 mg/L6-BA+0.5 mg/L NAA培养基与改良DKW+0.4 mg/L TDZ+0.4 mg/L IBA培养基诱导效果最好,研究发现低浓度的TDZ(0.2~0.4 mg/L)促进愈伤组织形成,高浓度的TDZ(0.8~2.0 mg/L)抑制愈伤组织形成。本研究可筛选出诱导叶片愈伤组织的最佳方法,为后期愈伤组织诱导不定芽提供科学依据。 展开更多
关键词 薄壳山核桃 品种苗 叶片 愈伤组织
Molecular and biological characterization of melon-infecting squash leaf curl China virus in China 认领
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作者 WU Hui-jie LI Meng +2 位作者 HONG Ni PENG Bin GU Qin-sheng 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第2期570-577,共8页
It has been reported that squash leaf curl China virus(SLCCNV)infects some Cucurbitaceae crops except for melon(Cucumis melo L.).A new disease of melon exhibiting severe leaf curl and dwarfing was observed in Hainan P... It has been reported that squash leaf curl China virus(SLCCNV)infects some Cucurbitaceae crops except for melon(Cucumis melo L.).A new disease of melon exhibiting severe leaf curl and dwarfing was observed in Hainan Province of China.In this study,the pathogen was identified as SLCCNV through biological and molecular characterization.The isolate(SLCCNV-HN)possess a bipartite genome,DNA-A(HM566112.1)with the highest nucleotide identity(99%)to SLCCNV-Hn(MF062251.1)pumpkin and SLCCNV-Hn61(AM260205.1)squash isolates from China,whereas DNA-B(HM566113.1)with the highest nucleotide identity(99%)to SLCCNV-Hn(MF062252.1).Phylogenetic analyses based on the full-length SLCCNV-HN DNA-A and-B sequences indicated that SLCCNV-HN melon isolate is clustered with SLCCNV-Hn pumpkin,SLCCNV-Hn61 and SLCCNV-SY squash isolates from southern China,forming an independent cluster.Infectious clone of SLCCNV-HN was constructed and the melon plants were inoculated and the infection rate is 100%,the systemic symptoms in melon showed identical to those of melon plants infected in fields.Additionally,melon plants transmission of this virus by Bemisia tabaci with a transmission rate of 95%(19/20)showed leaf curl and dwarf symptoms 15 days post transmission,thereby fulfilling Koch’s postulates.Analysis of genomic organization and phylogenetic trees indicated that SLCCNV-HN melon isolate belongs to the Begomovirus genus.To the best of our knowledge,this is the first characterization of meloninfecting SLCCNV through its genome,infectious clone and transmission. 展开更多
关键词 MELON SQUASH LEAF CURL China virus(SLCCNV) genome INFECTIOUS CLONE
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Effects of Fertilization and Transplantation in the Neighbouring Area on Quality of Artemisia argyi Leaf 认领
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作者 Juan WU Xiangluan WAN +2 位作者 Dingrong WAN Yujie CHEN Rui PU 《药用植物研究:英文版》 CAS 2020年第3期65-67,共3页
[Objectives]To make a preliminary study of the effects of the fertilizer application and transplantation from Qichun County,Hubei Province,China,to neighbouring area on the chemical substance contents and moxa yield o... [Objectives]To make a preliminary study of the effects of the fertilizer application and transplantation from Qichun County,Hubei Province,China,to neighbouring area on the chemical substance contents and moxa yield of Artemisia argyi leaf in Qichun(AALQ).[Methods]The content of the total flavonoids in AALQ was determined by UV-Vis spectrophotometry with apigenin as reference substance.The contents of volatile oil and tannins were determined by the methods in Chinese Pharmacopoeia(2015 edition).The moxa yield was detected by the self-developed method of grinding and sifting with high-speed pulverizer.[Results]Whether applying cake fertilizer,or compound fertilizer after applying barnyard manure,the contents of total flavonoids and tannins in AALQ were reduced in varying degrees,and the content of volatile oil was changed,which had adversely affect the accumulation of effective substances in the leaves of medicinal A.argyi as a whole.The contents of related chemical substances and moxa yield of A.argyi planted in the neighbouring Xishui County from Qichun,Hubei Province were relatively high.[Conclusions]The contents of effective substances and moxa yield of AALQ were significantly reduced as a whole when applied fertilizer in planting,especially after the application of barnyard manure,compound fertilizer was added.The quality of A.argyi leaf would not be adversely affected if it was transplanted from Qichun County,Hubei Province,which is the genuine producing area,to nearby areas with similar ecological environment. 展开更多
关键词 Artemisia argyi leaf in Qichun(AALQ) FERTILIZATION Cultivation in different places Volatile oil Total flavonoids TANNINS Content determination Moxa yield
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医科达Versa HD直线加速器MLC系统的故障分析与检修 认领
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作者 陈晓 刘旭红 +1 位作者 赵永军 王禅 《中国医疗器械信息》 2020年第16期171-173,共3页
Versa HD医用直线加速器是具有图像引导和容积旋转调强(VMAT)功能的高端放疗设备,MLC有80对叶片,主要形成治疗辐射野。MLC是直线加速器调强放射治疗的主要部件,治疗过程中移动频繁,并靠光学系统识别叶片反光点来确定叶片位置,故障率较... Versa HD医用直线加速器是具有图像引导和容积旋转调强(VMAT)功能的高端放疗设备,MLC有80对叶片,主要形成治疗辐射野。MLC是直线加速器调强放射治疗的主要部件,治疗过程中移动频繁,并靠光学系统识别叶片反光点来确定叶片位置,故障率较高。需定期对MLC系统进行保养,重点是清除灰尘。本文阐述了MLC发生的4例故障的分析和检修过程,并使用了部分随机配送维修工具进行故障判断和检修,希望能为其他维修人员维修同类设备提供参考。叶片的key由非金属材料制成,故障率最高。 展开更多
关键词 保养 叶片 丝杆 驱动组件 故障分析
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瓜蒌叶黄酮的提取工艺优化及其生物活性研究 认领
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作者 骆丽如 黄昭璇 +2 位作者 谢文杰 胡璐曼 唐忠海 《湖南生态科学学报》 CAS 2020年第2期24-30,共7页
对瓜蒌叶黄酮进行生物活性初步研究,探究瓜蒌叶作为天然食品添加剂的价值.在单因素试验和正交试验的基础上,结合极差分析法,得出水浴加热的条件下以乙醇为提取溶剂的最佳提取方法(固液比1∶60、提取时间2 h、提取温度70℃、乙醇质量分数... 对瓜蒌叶黄酮进行生物活性初步研究,探究瓜蒌叶作为天然食品添加剂的价值.在单因素试验和正交试验的基础上,结合极差分析法,得出水浴加热的条件下以乙醇为提取溶剂的最佳提取方法(固液比1∶60、提取时间2 h、提取温度70℃、乙醇质量分数60%);再在此条件下提取瓜蒌叶黄酮进行DPPH自由基清除试验,测定瓜蒌叶黄酮的抗氧化能力;再以大肠杆菌、黑曲霉、金黄色葡萄球菌作为试验对象进行抑菌试验,初步测定瓜蒌叶黄酮的抑菌能力.试验结果表明瓜蒌叶黄酮具有良好的抗氧化能力,但是在低浓度时抑菌效果并不明显,在提高浓度后或许会有不错的抑制效果. 展开更多
关键词 瓜蒌 黄酮 抗氧化 DPPH自由基 抑菌 OD600值
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The effect of artificial solar spectrum on growth of cucumber and lettuce under controlled environment 认领
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作者 ZOU Jie ZHOU Cheng-bo +3 位作者 XU Hong CHENG Rui-feng YANG Qi-chang LI Tao 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第8期2027-2034,共8页
Light-emitting diodes(LEDs)have been widely applied in the controlled environment agriculture,which are characterized by relatively narrow-band spectra and energetical efficiency.Most recently,the spectrum of Sunlike ... Light-emitting diodes(LEDs)have been widely applied in the controlled environment agriculture,which are characterized by relatively narrow-band spectra and energetical efficiency.Most recently,the spectrum of Sunlike LEDs has been engineered and it closely resembles solar spectrum in the range of photosynthetic active radiation(PAR,400–700 nm).To investigate how plant growth responses to the spectrum of Sunlike LEDs,cucumber and lettuce plants were cultivated and their responses were compared with the conventional white LEDs as well as composite of red and blue LEDs(RB,R/B ratio was 9:1).We observed that although Sunlike LEDs resulted in a longer stem in cucumber,dry weight and leaf area were similar as those under RB LEDs,and significantly higher than those under white LEDs.Moreover,cucumber leaves grown under Sunlike and white LEDs showed higher photosynthetic capacity than those grown under RB LEDs.For lettuce,plants grown under Sunlike LEDs showed larger leaf area and higher dry weight than the other two treatments.However,the leaf photosynthetic capacity of lettuce grown under Sunlike LEDs was the lowest.In this context,the spectrum induced plant functions are species-dependent.Furthermore,the three types of LEDs show distinct light spectra and they are different in many aspects.Therefore,it is difficult to attribute the different plant responses to certain specific light spectra.We conclude that plants grown under Sunlike LEDs exhibit larger leaf area,which may be due to some specific spectrum distributions(such as more far-red radiation),and consequently are favorable for light interception and therefore result in greater production. 展开更多
关键词 CUCUMBER leaf photosynthesis LETTUCE plant morphology Sunlike LEDs
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液滴荷电特性对水稻叶片表面接触角的影响 认领
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作者 张建桃 宋庆奎 +3 位作者 文晟 曾家骏 尹选春 兰玉彬 《河南农业科学》 北大核心 2020年第7期174-180,共7页
针对水稻叶片表面润湿性较差,喷洒作业时的药剂液滴容易从叶片表面滚落,药液利用率低的问题,研究液滴荷电特性对水稻叶片(倒二叶)表面接触角的影响。通过试验,研究荷电电压大小、电荷极性、电极环材料、电极环内径、NaCl含量等参数对水... 针对水稻叶片表面润湿性较差,喷洒作业时的药剂液滴容易从叶片表面滚落,药液利用率低的问题,研究液滴荷电特性对水稻叶片(倒二叶)表面接触角的影响。通过试验,研究荷电电压大小、电荷极性、电极环材料、电极环内径、NaCl含量等参数对水稻叶片表面接触角的影响。结果表明,随着荷电电压的增大,液滴在水稻叶片表面接触角整体呈先减小后增大的趋势,接触角在荷电电压为±4 kV时达到最小值;荷电正负极对水稻叶片表面接触角有明显影响,总体来说,液滴带负电荷时与水稻叶片表面的接触角较小;同种材料电极环条件下,随着电极环内径增大,液滴在水稻叶片表面接触角呈逐渐减小趋势;随着NaCl含量增大,液滴在水稻叶片表面接触角呈先减小后增大的趋势,不同品种水稻存在最佳的NaCl含量使接触角达到最小值。表明,通过调整液滴的荷电参数来减小液滴在水稻叶片表面接触角是可行的,对农药的高效利用具有重要参考意义。 展开更多
关键词 接触角 水稻 叶片 液滴荷电 电极环
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不同氮肥处理下高温胁迫对夏玉米产量及叶片超微构造的影响 认领
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作者 崔丽娜 董树亭 《玉米科学》 CAS CSCD 北大核心 2020年第1期92-97,共6页
以郑单958为材料,研究高温胁迫对夏玉米产量及叶片超微构造的影响。结果表明,高温处理缩短夏玉米的生育天数,降低夏玉米产量及叶绿素含量。随氮肥增加,高温处理对玉米产量的影响先降低后升高(在310.5 kg/hm~2氮肥下,高温处理玉米产量的... 以郑单958为材料,研究高温胁迫对夏玉米产量及叶片超微构造的影响。结果表明,高温处理缩短夏玉米的生育天数,降低夏玉米产量及叶绿素含量。随氮肥增加,高温处理对玉米产量的影响先降低后升高(在310.5 kg/hm~2氮肥下,高温处理玉米产量的降低达到27.2%、31.1%)。高温处理较对照维管束鞘细胞变大,高温处理维管束鞘细胞内的叶绿体出现淀粉粒,对照处理维管束鞘细胞内的叶绿体没有出现淀粉粒。高温线粒体及细胞核(被)膜开始解离,对照处理线粒体及细胞核(被)膜完整,说明高温条件下,玉米对氮的耐受力降低。高温处理叶绿体数、叶绿体基粒数减少及基粒片层数减少,叶绿体面积及叶绿体长/宽比值变小,高温处理较对照线粒体数先增加后减少。高温处理与对照叶肉细胞叶绿体内均未发现淀粉粒。 展开更多
关键词 玉米 氮肥 高温胁迫 叶片 超微构造
Higher leaf area through leaf width and lower leaf angle were the primary morphological traits for yield advantage of japonica/indica hybrids 认领
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作者 WEI Huan-he YANG Yu-lin +8 位作者 SHAO Xing-yu SHI Tian-yi MENG Tian-yao LU Yu TAO Yuan LI Xin-yue DING En-hao CHEN Ying-long DAI Qi-gen 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第2期483-494,共12页
The yield potential of japonica/indica hybrids(JIH)has been achieved over 13.5 t ha–1 in large-scale rice fields,and some physiological traits for yield advantage of JIH over japonica inbred rice(JI)and indica hybrid... The yield potential of japonica/indica hybrids(JIH)has been achieved over 13.5 t ha–1 in large-scale rice fields,and some physiological traits for yield advantage of JIH over japonica inbred rice(JI)and indica hybrid rice(IH)were also identified.To date,little attention has been paid to morphological traits for yield advantage of JIH over JI and IH.For this reason,three JIH,three JI,and three IH were field-grown at East China(Ningbo,Zhejiang Province)in 2015 and 2016.Compared with JI and IH,JIH had 14.3 and 20.8%higher grain yield,respectively,attributed to its more spikelets per panicle and relatively high percentage of filled grains.The advantage in spikelets per panicle of JIH over JI and IH was shown in number of grains on the upper,middle,and lower branches.Compared with JI and IH,JIH had higher leaf area through leaf width and lower leaf angle of upper three leaves,higher leaf area index and leaf area per tiller at heading and maturity stages,higher stem weight per tiller and K and Si concentrations of stem at maturity,higher dry matter weight in leaf,stem,and panicle at heading and maturity stages,and higher biomass accumulation after heading and lower biomass translocation from stem during ripening.Leaf width of upper three leaves were correlated positively,while leaf angle of upper three leaves were correlated negatively with biomass accumulation after heading,stem weight per tiller,and per unit length.Our results indicated that the grain yield advantage of JIH was ascribed mainly to the more spikelets per panicle and relatively high percentage of filled grains.Higher leaf area through leaf width and more erect leaves were associated with improved biomass accumulation and stem weighing during ripening,and were the primary morphological traits underlying higher grain yield of JIH. 展开更多
关键词 japonica/indica HYBRIDS plant-type TRAITS leaf morphology
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桑树叶片大小与质量的相关性 认领
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作者 金方伦 王贤玉 +4 位作者 韩世玉 罗朝斌 杨胜特 黎明 胡世叶 《湖北农业科学》 2020年第1期74-77,共4页
为探讨影响桑树(Morus alba L.)叶片净质量的主要因素,2017—2018年以农桑14号为试材,在生长季调查叶片长度、叶片宽度、叶柄长度、叶柄宽横径、叶柄厚横径、叶柄质量、叶片质量、千克叶片数量、叶片净质量等指标,分析了桑树叶片性状的... 为探讨影响桑树(Morus alba L.)叶片净质量的主要因素,2017—2018年以农桑14号为试材,在生长季调查叶片长度、叶片宽度、叶柄长度、叶柄宽横径、叶柄厚横径、叶柄质量、叶片质量、千克叶片数量、叶片净质量等指标,分析了桑树叶片性状的关系。结果表明,叶片长度、叶片宽度与叶片净质量呈高度正相关,叶柄长度、叶柄宽横径、叶柄厚横径与叶片净质量呈显著正相关;叶片长度、叶片宽度、叶片长度+叶片宽度、叶片长度×叶片宽度、叶柄长度、叶柄宽横径、叶柄厚横径、叶柄质量、叶片质量、千克叶片数量与叶片净质量的相关系数之间存在极显著差异(P<0.01);比较叶片长度等分别与叶片净质量形成的二次曲线方程和直线方程的相关系数,表明更符合二次曲线;各指标对叶片净质量的影响程度大小顺序为叶片质量、每千克叶片数量、叶片宽度、叶片长度、叶柄质量、叶柄厚横径、叶柄宽横径、叶柄长度。可以通过调查叶片宽度和叶片长度等指标进行桑园估产。 展开更多
关键词 桑树(Morus ALBA L.) 叶片大小 叶片质量 相关分析 农桑14号
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不同砧穗组合红富士苹果幼树叶片及枝条发育后期的生理特性 认领
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作者 王红平 刘兴禄 +3 位作者 牛军强 董铁 曹永华 马明 《甘肃农业大学学报》 CAS CSCD 北大核心 2020年第1期107-114,共8页
【目的】明确3年生不同砧穗组合对幼树生长期树体叶片形态和枝条生长特性生理发育的影响,为筛选陇东地区适宜的砧穗组合提供理论依据.【方法】以山定子为基砧,T337和M26做中间砧,其上嫁接‘烟富3号’和‘烟富6号’,测定6种砧穗组合幼树... 【目的】明确3年生不同砧穗组合对幼树生长期树体叶片形态和枝条生长特性生理发育的影响,为筛选陇东地区适宜的砧穗组合提供理论依据.【方法】以山定子为基砧,T337和M26做中间砧,其上嫁接‘烟富3号’和‘烟富6号’,测定6种砧穗组合幼树发育后期叶片的形态质量和枝条抗氧化酶活性以及营养物质等生理指标.【结果】利用中间砧T337和M26后虽然较对照降低了叶面积,但百叶干鲜重、百叶干重和叶绿素含量分别较对照增加显著;‘烟富3号’和‘烟富6号’利用中间砧T337后叶片和枝条组织中的POD、SOD、可溶性糖类以及叶片中N、P的含量均显著增加,中间砧M26的次之,无中间砧的对照最低,但MDA、K的含量恰恰相反.‘烟富6号’比‘烟富3号’绝大多数指标测定值都高.【结论】利用T337、M26及‘烟富6号’后,叶片和枝条营养丰富,新稍停长早有利于安全越冬.综合分析,适宜陇东地区栽培的苹果砧穗组合依次为‘烟富6号’/M26/山定子、‘烟富6号’/T337/山定子、‘烟富3号’/M26/山定子和‘烟富3号’/T337/山定子. 展开更多
关键词 砧穗组合 红富士苹果幼树 生理特性 叶片 枝条
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