试论草牧场防护林的结构效益和发展     

吕文 《林业实用技术》1991,(7)

本文论述了三北地区6种较典型的草牧场防护林的结构、效益及在草原发展中的意义,强调营造林带、林网、大片林、疏林、绿伞、生物圈、生物墙合为一体的、能在区域范围内自成防护体系的多功能结构的草牧场防护林。  相似文献   

应对气候变暖，中国关注森林碳汇工作动态     

吕文 《防护林科技》2005,(3):F002-F002

近期，为应对气候变暖这一威胁人类生存的重大环境危机，国内外有关组织和机构在中国加大了这方面的研究和行动。国际《京都议定书》确定了在全球实施减排（减少温室气体排放）和增汇（即增加CO2吸收）行动。  相似文献   

杨树对黄斑星天牛抗性的初步研究   总被引：18，自引：1，他引：18  

王希蒙  吕文  张真 《林业科学》1987,(1)

在调查时,发现黄斑星天牛(Anoplophora nobilis Gaglbauer)对不同品种的杨树其危害程度不同,为了探明其原因,对各杨树品种进行了生理生化方面的分析,以期找出与抗性有关的化学物质,进而为生产提供抗黄斑星天牛的树种。关于树木抗虫性的研究,国外Rick boling(1983)和Feeg(1970)有报道,国内尚未见报道,现将我们的研究结果介绍如下:  相似文献   

Extraction and characterization of Foeniculum vulgare pectins and their use for preparing biopolymer films in the presence of phaseolin protein     

Giosafatto CV  Mariniello L  Ring S 《Journal of agricultural and food chemistry》2007,55(4):1237-1240

Pectins from Foeniculum vulgare were extracted under acidic conditions. The obtained pectins were mainly composed of uronic acid but also contained traces of rhamnose, galactose, and arabinose. Extracted pectins were used as a carbohydrate source to prepare biopolymer films in the absence and in the presence of phaseolin protein. The swelling characteristics of the films were examined as a function of ionic strength, pH, and the applied osmotic stress. The swelling behavior was dominated by a Donnan-type effect, which decreases with increasing ionic strength and counterion valency. In all cases the swelling of films containing phaseolin was reduced, suggesting a network formation between protein and pectins. Mechanical property studies have also estimated the validity of the obtained novel biopolymer films in terms of mechanical resistance.  相似文献   

Synthesis and resistance to in vitro proteolysis of transglutaminase cross-linked phaseolin, the major storage protein from Phaseolus vulgaris     

Mariniello L  Giosafatto CV  Di Pierro P  Sorrentino A  Porta R 《Journal of agricultural and food chemistry》2007,55(12):4717-4721

The ability of phaseolin to act as an acyl donor and acceptor substrate of transglutaminase was studied by using an enzyme isolated from Streptoverticillium mobarense. Phaseolin, a trimeric storage protein from Phaseolus vulgaris L., was shown to possess both glutamine and lysine residues reactive for the enzyme. The extent of transglutaminase-catalyzed cross-linking has been studied in function of both incubation time and enzyme concentration. Native- and SDS-PAGE demonstrated that phaseolin is intra- and intermolecularly cross-linked by transglutaminase and gives rise to different polymers as well as to modified forms of the protein having a similar molecular weight but lower Stokes radius if compared to unmodified phaseolin. Cross-linked phaseolin was found to be more resistant to proteolytic cleavage than the unmodified counterpart, as demonstrated by in vitro trypsin and pepsin digestion experiments. This behavior could suggest novel possible uses of the transglutaminase-modified phaseolin.  相似文献   

再生稻气力式肥料集排装置的设计与试验     

柯烩彬  周勇  张国忠  吕文  刘沿  黄琳 《中国农业科技导报》2022,24(6):106-114

针对再生稻传统追肥作业中施肥量不均匀、肥料利用率低等问题,设计了一种气力式肥料集排装置。对影响施肥性能的主要因素进行四元二次回归正交旋转中心组合试验,以各行排肥量一致性变异系数作为评价指标建立回归模型,研究进肥角度、进肥高度、波纹管长度及排肥轴转速对各行排肥量一致性的影响。结果表明,影响此气力式肥料集排装置各行排肥量一致性变异系数的主要因素顺序为排肥轴转速>进肥角度>波纹管长度>进肥高度。采用Design-Expert10.0软件进行优化分析得出最佳的参数组合：进肥角度54°、进肥高度216 mm、波纹管长度200 mm、排肥轴转速47 r·min^-1,此时各行排肥量一致性变异系数为1.71%,施肥均匀性较好,能够满足再生稻追肥要求。  相似文献   

Immune responses against Yersinia ruckeri have no effect on colonization of rainbow trout,Oncorhynchus mykiss (Walbaum), by Gyrodactylus derjavini (Mikailov, 1975)     

Buchmann K  Nielsen ME  Nielsen CV 《Journal of fish diseases》2003,26(3):183-186

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无公害稀有水果—猕猴桃引种栽培试验     

吕文  李秀德 《烟台果树》1999,(2):8-9

猕猴桃是现今世界性新兴的一种稀有水果。它营养丰富,维生素C含量比梨和苹果高30多倍,并含有蛋白分解酸酶、硒、锗等微量元素。具有特殊的医药作用,不仅种子、叶、根、花、茎可以入药,果实除生食外,还可制作糖果、点  相似文献   

三北防护林体系工程建设综述   总被引：1，自引：0，他引：1  

吕文  戴晟懋  杨飞虎  张文明 《防护林科技》1999,(4):40-44

通过对内蒙古、甘肃两省生态工程建设情况的调查,阐述了三北防护林工程建设面临着良好的机遇和严峻的挑战,找出了工程建设中存在的投资不足、缺乏统一领导,规化与计划脱节等问题,并提出进一步加强三北工程的建议。  相似文献   

试论草牧场防护林的结构效益和发展     

吕文 《林业科技通讯》1991,(7):13-15

  相似文献