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1.
This work examined the processing yields, physico-chemical characteristics, and bioactive properties of Canadian organic cranberry and blueberry pomace and phenolic-enriched extractives. The ethanol extracts from each berry contained three to four times the soluble solids and sugar contents compared to the pomace. The lipid content of organic cranberry pomace (4.44%), cranberry ethanol extractives (3.86%), and blueberry ethanol extractives (4.44%) were significantly lower than the lipid content of the organic blueberry pomace (5.42%). The organic blueberry pomace showed higher protein content (8.41%) than organic cranberry pomace (5.76%); however, both organic cranberry and blueberry ethanol extracts showed similarly low protein contents. Significant differences were observed in the mineral and elemental contents of both pomaces and their extractives. Total phenolics, tartaric esters, flavonols, anthocyanins, and antioxidant activities were increased by two to three times in both organic cranberry and blueberry ethanol extracts compared to their respective pomaces. The major anthocyanins detected in organic blueberry pomace and ethanol extracts were peonidin 3-glucoside, malvidin 3-galactoside, malvidin 3-glucoside, and cyanidin 3-arabinoside. Peonidin 3-galactoside, cyanidin 3-galactoside, cyanidin 3-arabinoside, and peonidin 3-arabinside were the major anthocyanins in the organic cranberry and ethanol extacts. Results indicated that cranberry and blueberry pomace could be used to develop bioactives with antioxidant activity for potential health benefit and/or bioenergy production.  相似文献   
2.
The objective of this study is to determine the properties of G. amplexifolia. In this paper; the chemical composition, including holocellulose, acid-insoluble lignin, 1% NaOH solubility, benzene-ethanol extractives and ash content, was considered for the variability with respect to positions along bamboo culm height (bottom, middle and top), parts along radial direction (inner part and outer part)and ages (1-year and 2- year). The test results were also compared to those of moso that is commonly planted and used in China. This study indicated that both the holocellulosecontent and the lignin content in inner part were lower than ; in outer part, but for extractives and ash content, the reverse was true. Bamboo age also had effect on chemical composition; both the holocellulose content and the ash content in the culm of 1- year were higher than those of 2-year; while the lignin content and the extractive content m the culm of 1- year were higher than those of 2-year. High holocellulose content, low lignin contentand extractive content were advantages of G. amplexifolia.  相似文献   
3.
早在有史以前,人们已经利用那些易于获得的树木提取物为人类提供了许多必需品,以后,不同国家的科学家们经过长期互相协作研究,分离出其有效组分,阐明了它们的结构,作到了化学合成和生物合成,还确定了控制它们在植物中生成的某些生物因素。今天在有机化学上的许多进展都是从175年以前的这些研究中发展而来的。近年技术的发展,质量标准的提高以及价格竞争都要求有特殊性质的原料以满足特殊的需要。当今技术的迅速发展使国际间的出口局限于那些价格低廉、质量较高的基本原料,或具有不能替代的特有成分的产品。在资源日益减少的今日世界必须更重视特定地区再生资源的保护和最大限度的发展,以及生产所需产品的最有效的技术。为此目的,对树木的生理和化学还需要更深刻的认识。  相似文献   
4.
A method for screening wood extractives was developed using cellulose thin-layer chromatography plate (Cell-TLC) separation and was directly applied to bioassays. Wood meal (60 mesh) from nangka (Artocarpus heterophyllus Lamk) heartwood was extracted with hot methanol. The crude extract was separated using a Cell-TLC plate (50 × 50mm). Two broad bands with Rf values of 0.46 and 0.96 were found, and the bands showed completely different effects against the pest termite Coptotermes formosanus Shiraki and the decay fungus Fomitopsis palustris. The band with Rf 0.46 was preferentially consumed by workers of C. formosanus, and it did not show any growth inhibition against F. palustris when the Cell-TLC plate was directly exposed to the organism. In contrast, the band with Rf 0.96 appeared to repel strongly the feeding by C. formosanus and inhibited the growth of F. palustris. It was concluded that the Cell-TLC system was applicable for screening wood extracts consisting of many compounds.  相似文献   
5.
采用硫酸水解法(aldito-acetate procedure)、X射线粉末衍射(XRD)、傅里叶变换红外光谱(FTIR)分析了蒸爆过程中毛竹材加工剩余物纤维聚集态结构及主要化学成分的变化.研究结果表明,(1)毛竹材加工剩余物经蒸爆处理,60%左右的半纤维素水解,木质素低分子化且裸露到纤维表面,易被80%乙醇及木质素溶剂提取,从而实现毛竹材加工剩余物主要组分的有效分离.(2)毛竹材加工剩余物经蒸爆处理,80%乙醇抽提物得率提高,综纤维素得率减少,木质素含量减少:葡萄糖相对含量增加,半纤维素降解明显.(3)210℃处理10 min和220℃处理10 min的蒸爆浆的化学组成变化几乎没有区别,但两者与200℃处理10 min差别较大,210℃处理10 min是毛竹材加工剩余物适宜的处理温度.(4)FTIR结果显示蒸爆处理后在1040~1060 cm-1区的吸收峰分裂为明显的2个峰表明半纤维素降解,1166 cm-1处的吸收强度明显减弱,表明C-O-C键有不同程度的断裂.X-身寸线衍射分析结果显示毛竹材加工剩余物蒸爆处理后纤维素相对结晶度增加.  相似文献   
6.
Summary Although organic solvents such as methanol and ethanol have been shown to act as energy sources for denitrifying microorganisms, no studies on the influence of organic solvents on denitrification in soil have been reported. Organic solvents have been used as an aid in the application of pesticides and other agricultural chemicals to soil, in studying the effects of these chemicals on denitrification in soil. During these applications, the soil is often aerated or heated to remove the solvent while leaving the chemical in the soil. The work reported here shows that treating soils with methanol, ethanol, or acetone had a very marked effect on their denitrifying ability, even when the soils were aerated thoroughly or heated at 50°C to remove these solvents. This indicates either that it is not possible to effect complete removal of organic solvents from soils by aeration or heating or that organic solvents promote denitrification by solubilizing a fraction of soil organic matter that is not available to denitrifying microorganisms before the addition of these solvents. Experiments using phenylmercuric acetate (a herbicide and nitrification inhibitor) showed that although this compound had a marked inhibitory effect on denitrification when added to soil in methanol, ethanol, or acetone, it had no inhibitory effect on denitrification when added to soil in water. The work reported shows that the use of an organic solvent in adding an agricultural chemical to soil can lead to erroneous conclusions in studies on the effects of the chemical on soil denitrification.  相似文献   
7.
莫梅英  冷扬  张志 《湛江医学院学报》2007,25(3):250-251,260
目的利用微核试验了解松木刨花和枫木刨花的遗传毒性。方法80只NIH种小白鼠随机分为8组,每组10只。其中3组分别以100、50、12.5g/kg剂量的松木刨花水提取物染毒,另3组分别以100、50、12.5g/kg剂量的枫木刨花水提取物染毒,1组(阳性对照组)以环磷酰胺50mg/kg染毒,1组((阴性对照组)以生理盐水染毒。染毒方法均是先经口染毒,24h后以同样剂量再次灌胃。6h后颈椎脱臼处死动物,制片,观察并计数嗜多染红细胞的微核率。结果以松木刨花及枫木刨花水提取物染毒的各组小白鼠的微核率与阳性对照组比较差异有统计学意义(P<0.01),与阴性对照组比较差异无统计学意义(P>0.05)。结论松木刨花和枫木刨花的水提取物对小鼠的骨髓细胞未见有何致突变性。  相似文献   
8.
植物抗氧化剂研究展望   总被引:13,自引:1,他引:13  
总结了植物多酚、活性多糖、维生素、蛋白质和氨基酸等植物提取物的抗氧化活性主要成分,提出应在原料筛选,提取、分离方法创新,多组分协同作用机理和抗氧化活性成分的构效关系等方面深入研究  相似文献   
9.
研究了0.15、0.30、0.75、1.50 g/L 4种不同硝酸钠营养浓度条件对雨生红球藻生长状况的影响,同时探究了该试验条件对雨生红球藻中虾青素起始积累期和后期积累量的影响,以寻找既能使雨生红球藻在氮源用尽后细胞密度达到或接近最大,同时又能最快直接进入虾青素积累阶段的硝酸钠营养添加浓度。试验结果表明,硝酸钠浓度为0.15 g/L时雨生红球藻细胞生长状况最好,细胞浓度最高可以达到5.19×105个/ml。此条件下细胞尚未停止生长即已有细胞开始积累虾青素,变红(培养的第23天)。使用有机溶剂萃取法以丙酮提取虾青素,硝酸钠浓度为0.15 g/L时,最终虾青素浓度达到19.136 mg/L,是其他硝酸钠浓度下的虾青素含量最大值。  相似文献   
10.
采用丙酮萃取法从新鲜水化大豆油脚中提取粉末大豆磷脂。提取时第一次油脚:丙酮=3∶1,第2—6次原料:丙酮=1∶1。第1—3次离心后的提取液用于油和丙酮的回收,第4—6次离心后的提取液贮存,用来代替下一次生产1—3次的纯丙酮.从油脚提取的磷脂颜色(淡黄色)好于从浓缩磷脂中提取的(淡棕色),前者酸值,过氧化值较后者低.  相似文献   
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