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41.
黑龙江省不同类型土壤微量元素含量及对稻米品质的影响   总被引:5,自引:0,他引:5  
采用单因素方法研究黑龙江省不同类型土壤铜、锰、铁、锌微量元素含量与稻米子粒铜、锰、铁、锌微量元素的关系及其对稻米品质的影响。结果表明,不同类型土壤铜含量顺序为白浆土>黑土>草甸土>盐碱土,锰和铁的含量顺序与铜一致,锌的含量则是黑土>白浆土>草甸土>盐碱土。土壤中的铜、锰、铁、锌含量与水稻子粒中各微量元素含量达极显著正相关;水稻子粒中铜、锰、铁、锌含量高,稻米整精米率、长宽比和食味评分降低,蛋白质含量和垩白粒率升高;各微量元素对于稻米出糙率和直链淀粉含量的影响不一致,子粒中铜、锰、铁含量高,稻米出糙率高,锌含量与稻米出糙率则相反,各微量元素对于稻米的出糙率影响不大,铜和锌含量低,锰和铁含量高,稻米的直链淀粉含量高,子粒中各微量元素与稻米品质指标的关系间接反映出各类土壤微量元素含量与稻米品质指标的关系。  相似文献   
42.
土壤矿物质吸附砷的研究进展   总被引:24,自引:1,他引:24  
石荣  贾永锋  王承智 《土壤通报》2007,38(3):584-589
砷是一种有毒的重金属元素,由于自然和人为的原因,世界上的许多国家存在砷污染问题,因此有关砷污染的研究与控制日益受到人们的关注。本文介绍了土壤砷污染的产生原因及污染状况,重点集中在探讨土壤中的各种矿物质对砷吸附行为的作用机理。这些矿物质包括铁铝氧化物和氢氧化物、锰氧化物、黏土矿物和碳酸盐类。关于砷在各类矿物质上的吸附机理,普遍接受的观点认为:砷氧阴离子与矿物质的表面发生了配位体交换过程并通过共价键的作用,形成了表面配位体。表面配位体以内层双齿双核鳌合形式为主,受矿物质的种类、pH值和氧化还原电位等因素的影响,外层吸附和其他鳌合状态可能存在。砷在土壤矿物质上的吸附效果强烈依赖于体系的pH值,这与吸附的理论模型和数学计算结果相一致。矿物质的种类、组成、结晶状态和表面积等影响了砷的吸附过程和吸附效果。土壤中存在的各种阴阳离子通过与砷阴离子竞争吸附位而影响砷在矿物质上的吸附。  相似文献   
43.
Eighteen growing Awassi lambs were used in this study to determine the effect of supplementing two levels of yeast and methionine (cyc-methionine) on the trace elements bioavailability, growth rate, and general performance. The lambs were divided to three groups. The dietary treatments were the control diet (C), control diet plus 2 g cyc-methionine/lamb/day (T1) and control diet plus 4 g cyc-methionine/lamb/day (T2).

Lambs fed 2 g/day of cyc-methionine (T1) showed a significantly higher (P < 0.05) copper, zinc, and cobalt concentrations in liver and meat tissues, but not the same trend in kidney. No significant (P > 0.05) effect of time and time × treatment interaction on copper, zinc, cobalt, and manganese concentrations in blood serum, but cobalt and manganese concentration showed significant (P < 0.05) change by time. Moreover, a significantly (P < 0.05) higher total body gain, average daily gain, dressing percentage, and lower feed conversion were detected in lambs from T1 compared with the control and T2 groups.

Feeding 2 g of cyc-methionine to growing lambs increased the net profit by $6.017/lamb and only $3.52/lamb fed 4 g cyc-methionine/day when compared with the control group.

In conclusion, feeding growing Awassi lambs yeast and methionine in a form of cyc-methionine, with a low level of 2 g/day, improve the bioavailability of copper, zinc, and cobalt by growing lambs and their growth performance.  相似文献   

44.
Chestnut cultivation and production in Spain has employed grafted seedlings from selected local cultivars. Previously, we have characterised the Spanish cultivars by morphological and molecular markers. We are presenting in this paper the proximate analysis and mineral content for the main Spanish cultivars. A total of 131 samples were collected from 47 cultivars in six important Spanish chestnut production regions; located in the North such as Asturias, Castilla-León (El Bierzo) and Galicia; in the Central such as Extremadura and in the South such as Andalucía; as well as the Canary Islands, the southermost part of Spain near to North Africa. High variability in chemical composition between cultivars and regions corresponded to the high genetic variability between cultivars. Correlations with environmental parameters were low, indicating that differences found between regions were probably reflecting the differences between cultivars. In Central and Southern Spain, some cultivars presented lowest moisture content due to the low summer rainfall in these regions. Differences in starch and total sugar contents were high and were negatively correlated with each other. There was no negative correlation between nut size and total sugar content. Lowest values of fibre content and ease of digestibility were found in cultivars from Galicia and Extremadura. No significant differences in Fe, Zn and Cu were found although Zn content is twice the value reported for European chestnuts. This work would be a valuable reference to chestnut quality for the food processing industry, nutritionists, breeders and growers alike.  相似文献   
45.
To determine the effects of two diets and water supplies on intestinal pH and mineral concentrations in the colon of horses, and to identify whether differences in these parameters exist in horses with and without enterolithiasis, surgical fistulation of the right dorsal colon was performed in six adult horses, three with and three without enterolithiasis. Each horse underwent four feeding trials: grass hay and untreated water, alfalfa hay and untreated water, grass hay with filtered/softened water, and alfalfa hay with filtered/softened water. Samples of colonic contents were analyzed for pH, dry matter, and mineral concentrations.Horses with enterolithiasis had higher calcium, magnesium, phosphorus and sulfur concentrations and higher pH in colonic contents than controls. Horses fed alfalfa had lower colonic sodium and potassium, higher calcium, magnesium, phosphorus and sulfur concentrations, and a more alkaline pH than those fed grass. Grass hay consumption leads to reduced concentrations of select minerals and a more acidic colonic environment compared with alfalfa, probably beneficial in the prevention of enterolithiasis. Under controlled dietary and management conditions, horses with enterolithiasis have differences in colonic mineral and pH parameters that may be consistent with physiological differences between horses with and without the disease.  相似文献   
46.
采用电感耦合等离子原子发射光谱方法测定了13个不同颜色樱桃番茄品种Ca、Cu、Fe、Mg、Mn、Na、Zn含量。分析结果表明,樱桃番茄含有丰富的适合人体吸收的矿物元素,Ca、Na、Mg含量较高,Cu、Fe、Mn、Zn含量较低;果皮矿物元素含量明显高于果肉含量;品种是造成矿物元素含量差异的主要因素。  相似文献   
47.
In arid and semi-arid regions, where water availability is a major limitation in crop production, using alternative water resources, such as saline water is one way to utilize lands. Chamomile (Matricaria recutita L.) as an annual medicinal herb may be considered as an economic substitute for field crops irrigated with fresh water since it has adaptability to wide range of climate and soil. A field examination was conducted during 2004–2005 using complete randomized block design with four replications in order to evaluate the effects of saline irrigation water on morphological characters, mineral content, oil quantity (content, yield), oil composition and apigenin content of chamomile. In each plot, 0.6 g/m2 of seeds were grown in 4 rows. The irrigation water had five different salinity levels (0, 4, 8, 12 and 16 dS m−1). The investigated characters through cultivation were fresh weight of flower (g), dry weight of flower (g), dry weight of aerial stems (g), dry weight of root (g), oil yield (kg/h), oil content (%), oil quality and apigenin content (%). After harvesting, the content of minerals (Na+, Cl, K+, Ca2+, Mg2+) were evaluated in aerial parts and roots of each plot. Mean comparisons for fresh flower weight in different treatments showed that fresh flower yield decreased with increasing salinity and it was higher in control compared to others. Analysis of variance showed that saline irrigation water had no significant effect on oil quantity (yield and content), oil quality (chemical composition) or apigenin content. Our results showed that chamomile is able to maintain all its medical properties, under saline condition and could be cultivated economically in such conditions.  相似文献   
48.
Chenopodium spp. is being used as a leafy vegetable and subsidiary grain crop in different parts of the world due to its rich nutritional quality and its ability to grow in stress conditions. A field experiment was conducted in Lucknow (India) to assess the genetic diversity in 40 accessions of Chenopodium spp. based on mineral composition of the leaves. Principal Component Analysis (PCA) showed that the first 4 PCs (Principal Component) accounted for 74.70% of the total variance among the accessions. The first PC (PC1) accounted for 41.96% of the total qualitative variation and had nickel, zinc and chromium with high positive and copper with high negative coefficients. The most important loadings for PC2 were calcium and potassium. Cluster analysis grouped the accessions into 4 major clusters. The first cluster, which showed maximum diversity, had 17 accessions, all of C. quinoa having high content of most of the heavy metals viz. zinc, chromium, nickel and cadmium. Cluster II was the largest consisting of 18 accessions which had low content of nickel, cadmium and chromium. Cluster III contained 3 accessions that had lowest amount of calcium, iron, magnesium and zinc, while accessions in cluster IV were characterized by high levels of calcium, sodium, magnesium, nickel, chromium and cadmium. Significant genotypic differences existed in the heavy metal uptake by plants. Mineral uptake and concentration in Chenopodium spp. corresponds to the taxonomic categorization in the genus and could also be utilized as a supplementary taxonomic tool for grouping together of closely related taxa. Conclusively the diversity can be exploited in plant breeding programs for increasing nutritional value and for bioremediation purposes.  相似文献   
49.
为了确定平顶山地区张良姜合理的遮阳网密度,通过遮阳试验(0%遮阳、50%遮阳、70%遮阳)研究了不同密度遮阳网对张良姜在植物学性状、子姜数量、重量和主要物质含量的差异。结果表明,遮阳网处理均可提高张良姜的植物学性状、生姜仔姜性状指标和单株重,张良姜姜块的粗纤维在遮阳条件下较高,锌、镁0%遮阳下含量较高,50%遮阳处理钙含量高。综合各项指标50%遮阳网处理表现较优,可在平顶山地区推广,为指导生产提供良好的理论依据。  相似文献   
50.
【目的】为了更好地开发利用洋葱的食用价值和保健功能提供依据。【方法】以河北、山东、昆明、甘肃4个产地的白皮洋葱和紫皮洋葱为研究对象,对其基本营养成分、矿物质成分、氨基酸成分进行分析比较,明确其差异性,可为深入研究洋葱的品质评价和资源开发利用提供基础资料。【结果】河北产地紫皮洋葱的基本营养物质含量、矿物质含量最高,氨基酸含量仅次于山东产地紫皮洋葱。【结论】河北产地紫皮洋葱可作为高值化开发利用的理想资源。  相似文献   
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