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1.
通过扫描电镜观察芝麻苗期叶片表面腺毛的显微结构,以二氯甲烷作为溶剂提取腺毛分泌物,并用GC/MS鉴定正常和干旱条件下不同芝麻品种叶片腺毛次生代谢物的差异。结果显示,苗期芝麻叶片表面存在非腺体腺毛、长柄腺毛、短柄腺毛及无柄黏液毛等多种腺毛类型,叶表面气孔属于毛茛型;芝麻叶腺毛分泌物包含多种组分,其中峰面积>2%的组分是主要代谢物,主要由酯类及直链饱和烷烃物质组成,品种间具有显著差异;干旱条件下,分泌物的组分显著改变,抗旱性较强的冀9014有10个组分的相对含量高于其他品种,这些组分包含三十六烷与三十四烷类物质。上述结果表明,用GC/MS鉴定芝麻叶表面腺毛分泌物是可行的,分泌物组分可以反映品种间的差异,并能揭示干旱条件对芝麻代谢的影响。可以认为,芝麻腺毛与腺毛分泌物组分在芝麻种质资源鉴定及抗旱种质选育中具有重要的应用价值。  相似文献   

2.
采用气相色谱和质谱联用(GC—MS)方法,研究甲醇、乙醛、乙酸乙酯、1-丙醇、异丁醇和异戊醇等挥发性物质在白兰地蒸馏时的含量变化规律。结果表明,比乙醇沸点低的乙醛和乙酸乙酯在酒头中的含量较高;比乙醇沸点高的1-丙醇、异丁醇和异戊醇在酒头末期和酒身前期的含量较高;甲醇的沸点虽然比乙醇低,但它在酒头和酒尾中的含量都较高,而在酒身中的含量较低。  相似文献   

3.
Sesame (Sesamum indicum L.) is one of the most important oil seed crops, which has been used as a traditional health food. The objective of this study was to investigate the changes of leaf cuticular waxes during plant growth from 5 to 75 days after seedling emergence, and the variation of leaf waxes with different leaf position; top, middle, and lower positions, using four Korean sesame cultivars, Ahnsan, Danbaeck, Hanseom, and Kyeongheuk. Alkanes in lower leaves and aldehydes in top leaves among leaf positions were the most abundant, with alkanes being with major portion in all leaf position of four sesame cultivars. Total leaf wax load decreased around three-fold between 5 and 30 days, and then remained constant up to day 75. The percentages of alkanes and aldehydes increased between 5 and 15 days and then changed little or increasingly, showing minor variation depending on sesame cultivars. The rate of increase of alkanes was slightly higher than that of aldehydes. Chain length of alkanes and aldehydes became longer from 5 to 30 days, and then remained almost constant till day 75. The major homologue in alkanes was the C29 at day 5 and the C33 constituent after day 30, while the major homologue in aldehydes was the C32 constituent continuously during leaf development. The results demonstrated that the chain length for alkane and aldehyde constituents changed increasingly by chain elongation and wax biosynthesis during leaf development of sesame.  相似文献   

4.
By the study of the technics of dry method milling,glazing and once moulding between matrix and glazing,and with the X rays and SEA methods, it is testified that using the new technics is in reasonable and advanced by the study of the microstructure and macroscopieial performance and character.The performance of the product is stable and the link between matrix and glazing is excellent. [WT5HZ]  相似文献   

5.
This paper introduces the clarifying influence of the intertube spacing, the tube arrangement,the heat flux and the working fluid on boiling heat tra(?)sfer of smooth tube bundles. The tube bundles include the arrangements of twin tubes, triple tubes, seven tubes and thirteen tubes. The relative intertube spacing of the tube bundles is from 0. 9 to 3. 3. Experimental results show that the tube position and intertube spacting have no effect on boiling curves for the region of fully-devoloped boiling. And they considerably affect the heat transfer coefficient for the transition region between natural convection and nucleate boiling. In general,the heat transfer coefficient in the transition region for the upper tubes can be enhanced by 0. 5 to 1. 5 times.  相似文献   

6.
Use of the X ray diffraction method to measure microball coat thickness is studied. A mathematical model of X ray diffraction of microballs is created and solved using computer aided simulation. The relationship between diffracted X ray intensity and coat thickness is calculated with the help of a standard sample possessing a known thickness. The coat thickness of other samples can be calculated by the intensity of diffracted X ray based on the same condition. The experimental result shows that this method is a rapid, convenient, non destructive means of measuring microball coat thickness.  相似文献   

7.
胡建广  林盛 《作物学报》1995,21(5):612-617
采用3次重复的随机区组设计,用16个巴西橡胶(Hevea brasiliensis)无性系幼龄树为材料,研究了13个数量性状的遗传参数,分析并比较了11个性状的广义遗传力,相关遗传力,遗传与表型变异系数,相对与绝对遗传进度;同时估算了各性状对试割产量的相关遗传变异贡献率和间接选择的相对效率。本文还估算了遗传相关信息与遗传相关贡献,并建立了综合选择指数。上述研究结果揭示,叶脉参考角度,乳管堵塞指数和  相似文献   

8.
为了解花朵中挥发性气味物质对吸引传粉昆虫采集所起到的作用,采用固相微萃取(SPME)和气相色谱-质谱联用(GC-MS)技术,检测梨花和油菜花全花、花药、花蜜中挥发性气味物质成分,并进行主成分及与昆虫采集相关性分析。鉴定梨花中挥发性气味物质成分有9种,氧烷类为主要挥发性气味物质,占44.44%,通过主成分分析,气味贡献物主要来自于二甲基硫醚、十四甲基环七硅氧烷、苯丙腈、苯甲醛等化合物。油菜花中挥发性气味物质成分有23种,酯类和氧烷类为主要气味挥发性物质,分别占8.7%和16.09%,气味贡献物主要来自于反-2-己烯醛、异硫氰酸-2-苯乙酯、4-异硫氰酸根合-1-丁烯、二甲基三硫醚、二甲基二硫醚等化合物;花药的挥发性气味物质种类比花蜜中更丰富。传粉昆虫调查发现,试验地共有传粉昆虫4目10科11种,梨和油菜传粉昆虫数量上有显著差异(P<0.05),但各成分与采集昆虫数量均没有显著相关性(P>0.05)。研究发现梨花和油菜花挥发性气味物质成分有显著差异,将为研究气味物质主要贡献物在吸引传粉昆虫中发挥的作用提供参考。  相似文献   

9.
采用同时蒸馏萃取法(SDE)对镇江恒顺香醋进行预处理,应用毛细管气相色谱(CGC)和色质联用(GC/MS)技术对其进行定性定量分析,对同时蒸馏萃取法的结果进行了分析。结果表明,镇江恒顺香醋中低沸点的物质含量较多,镇江恒顺香醋中检测出了32种香味成分,有酸类、酯类、醇类、酮类、醛类、杂环化合物等。主要香气成分有:酸类10种,醇类8种,酯类1种,醛类1种,酮类3种,其中醋酸、吡啶、四甲基肼、3-戊醇、2-糠醛、戊酸、1,1-二乙酰基乙烷、2-羟基-2-甲基-丙酸、肉桂酸、己酸、苯甲酸在镇江恒顺香醋中的含量较高。这些香味物质糅合在一起赋予镇江香醋的独特香气和风味。  相似文献   

10.
Sex-linked SSR markers in hemp   总被引:3,自引:0,他引:3  
J. Rode    K. In-Chol  B. Saal    H. Flachowsky    U. Kriese  W. E. Weber 《Plant Breeding》2005,124(2):167-170
Hemp is a dioecious plant with sex chromosomes X and Y, the male sex being heterogametic. The quality of the fibre depends on the sex type. The sex chromosomes can be characterized by molecular markers. In this report, sex‐linked simple sequence repeat (SSR) markers are described. One SSR marker was polymorphic in both the populations derived from single crosses, two other markers in but one of the two populations. Three alleles were detected for two SSR markers indicating polymorphism not only between X and Y, but also between different X chromosomes. In addition, several sex‐linked RAPD markers were detected in one population. Recombination within the sex chromosomes was observed for nearly all markers.  相似文献   

11.
On the basis of the mechanism of the boiling heat transfer on low finned tube, the influence of the geometric parameters of low finned tube on boiling heat transfer is synthetically analyzed and relevant criteria which affect the optimal structure of low finned tube is deduced in this paper. The boiling heat transfer experiment on low finned tube is conducted. Distilled water and R-113 are used as test fluids The experiment is performed at local atmospheric pressure. Synthesizing a large amount of experimental data, the semiempirical equations for the optimal geometric parameters of lowfinned tube are established  相似文献   

12.
植物角质层蜡质是一类覆盖于植物表层的疏水有机化合物,在保护植物免受生物与非生物逆境胁迫中发挥着重要作用。为了更好地了解和认识角质层蜡质在夏季绿肥作物抗逆性中的作用,选择柽麻(Crotalariajuncea)、田菁(Sesbania cannabina)和竹豆(Phaseolus calcaratus) 3种夏季豆科绿肥作物,鉴定茎和叶蜡质组分,并分析蜡质总量、各组分含量及碳链分布特征。共鉴定出8类化合物,包括脂肪酸、初级醇、醛、烷烃、烷基酯、二醇、萜类和固醇类化合物,其中前4种以同系物形式存在且为所有植物茎和叶共有成分(柽麻茎中未检出脂肪酸),说明烷合成和醇合成途径是主要的2种蜡质合成途径。田菁茎中鉴定出二醇化合物,其结构初步解析为1,18-30烷醇和1,16-30烷醇。3种绿肥作物茎和叶蜡质总量存在显著种间及部位差异,其中柽麻茎蜡质总含量为16.33μgcm^-2,显著高于田菁茎(6.45μg cm^-2)和竹豆茎(0.72μg cm^-2)。就茎和叶比较,柽麻茎显著高于叶片,其他2种植物茎和叶之间无显著差异。柽麻茎蜡质中,烷烃为优势成分,占蜡质总量的57.38%;叶片以初级醇为优势成分,占蜡质总量的50.12%。田菁茎、叶蜡质中的优势成分均为初级醇,分别占总蜡质的30.12%和71.21%。竹豆茎、叶蜡质中的优势成分均为烷烃,分别占总蜡质的40.79%和39.27%。各组分优势化合物的碳链长度在不同物种、不同部位也存在一定差异,说明参与蜡质合成的基因在物种、器官间有所不同。这些结果为今后从分子水平上揭示角质层蜡质参与夏季绿肥作物抗逆机制提供了理论基础。  相似文献   

13.
M. Hühn 《Plant Breeding》1992,109(1):28-34
In many fields of application in plant breeding and crop science, ratios of two component traits X and Y are of interest (harvest index in cereals, leaf-to-stem ratio in forage legumes, height-to-diameter ratio in forest trees etc.). When selection is practised on the ratio X/Y of two traits X and Y, the experimenter may be interested in the resulting changes of both trait means. Based on improved approximations for the covariances between X and X/Y and between Y and X/Y and for the variance of X/Y the changes in the means of X and Y can be predicted by applying the regression approach from conventional selection theory. Explicit expressions for these correlated responses in X and Y when selection is practised on their ratio X/Y are derived and discussed. The different outcomes (decrease, zero change or increase) for the selection pressures on X and Y are characterized by phenotypic coefficients of variation of X and Y, phenotypic and genotypic correlations between X and Y and heritabilities of X and Y.  相似文献   

14.
The impulse value of a impulse mechanism has a notable influence on the dynamics capability of impulse variable speed device. Basing on this point, the authors take crank-rocker mechanism in series with slider-crank mechanism as impulse mechanism when we design the impulse variable speed device. The link used to adjust the speed is applied in slider-crank mechanism which has no quick-return characteristic, so the advance-to return-time ratio keeps stable when we adjust its speed. The speed fluctuation also keeps invariable. The new method overcome the default that this kind of impulse variable speed device has a notable speed fluctuation. At the same time, ADAMS software is used to optimize and show the real motion law. From the simulation result we can get the speed fluctuation is down to 18% in the whole process. The change of speed fluctuation is down to 1%. The result is better than other mechanism like this category.  相似文献   

15.
Field investigations were carried out at the Agricultural College and Research Institute, Madurai, India during 1989—1990 to study the genotypic character association in sesame. The F4 and F5 generations of TSS6 X TMV3 and TMV3 X TSS6 were raised and eight genotypic characters were recorded: plant height; primary branches; secondary branches; capsule number per plant; seed number per capsule; 1000 seed—weight; oil content and seed yield per plant. Correlation studies showed that the magnitude and direction of correlation between eight pairs of traits varied with generations in both crosses involving two genotypes reciprocally. Single plant yield had a strong significant and positive relationship with capsule number in both generations of the two cross combinations indicating the close link between the two traits. The path coefficient analysis revealed that direct and indirect contributions by different traits primary branches, secondary branches, capsule number per plant, seed number per capsule and 1000—seed weight had to be considered as the most important traits in the determination of seed yield and selection of parents.  相似文献   

16.
Based on analysis of pool boiling characteristics outside low finned tube, this paper describes a simple method, using enhancing shroud to improve the performance of boiling heat transfer outside the low finned tube. The experiment results show that the boiling heat transfer coefficient can be 7-up to 10-fold enhanced by using shroud. The efficiency of a shroud is related to the size of two windows, heat flux and physical characteristics of test fluids.  相似文献   

17.
以蛋白液为原料,开发低胆固醇方便即食蛋制品、扩大蛋白液利用范围,研究鸡蛋干加工配方和关键工艺参数,并对添加剂、干物质含量、熟制工艺方式、卤制工艺方式对鸡蛋干产品品质的影响进行了研究。研究表明,添加蛋液1.5%的复合磷酸盐,干物质含量19%,采用热风干燥定型,经沸水煮1 h—放置1 h—煮1h,即可得到味美可口的鸡蛋干产品。  相似文献   

18.
X ray computer tomography for the measurement of triaxial stresses within a low atomic order material is presented to aim at the shortcoming of conventional X ray stress analysis and AST2001 X ray stress analyzer of USA. The device for X ray computer tomography of residual stresses and the measurement theory is discussed. The computer procedure for the measurement of X ray computer tomography is designed. With the diffraction data provided, complete triaxial stresses of an arbitrary point on the surface of and within material investigated can be evaluated. The stress tensors, stress gradients and stress free lattice spacing of material investigated can also be calculated. And a self control mechanism for measurement and evaluation is presented.  相似文献   

19.
Abstract: With the increase of global integration, the peri‐urban area (PUA) of megacities in Asia has become a favourite destination for foreign direct investment (FDI). This paper uses the PUA of Shanghai as a case study to investigate the impact of global forces on the urban expansion of the city, and the link between urban growth and sustainable development in this mega‐urban context. Shanghai has grown impressively during the past two decades in terms of economic and physical transformation. Much of this transformation has rested on the unbridled exploitation of land and other environmental resources in its peri‐urban area. This is characterised by the designation of development zones and the concentration of manufacturing FDI, resulting in dispersed growth and environmental degradation. The disruption of the physical environment, combined with the concentration of the urban poor in these areas (in particular ‘temporary migrants’), has turned the PUA into a potential crisis point threatening the social and economic development of the city.  相似文献   

20.
以新鲜葛根为原料,采用制片、干燥、粉碎等工艺制备葛根全粉,以全粉的碘蓝值、色泽为评价指标,研究了护色剂、护色时间、蒸煮时间和热风干燥温度对全粉品质的影响。结果表明,烘干温度是影响碘蓝值的主要因素;最佳制备工艺参数:护色剂及质量分数为0.35%柠檬酸和0.30%焦亚硫酸钠,护色时间60 min,蒸煮时间16 min,烘干温度60℃。  相似文献   

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