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81.
82.
Abstract Copper absorption by roots or leaf and transport to other parts were followed in 9‐days old bean (Phaseolus vulgaris L. cv. Vaghya) seedlings. Translocation was also measured in 4 cm segments of the stem. It was found that larger amount of Cu was retained in the roots and Cu was more mobile through phloem than through xylem, as indicated by the data on translocation from root and leaf. Bean plants were found to translocate more Cu to the stem than to other parts. Kinetic analysis of absorption by excised roots and stem segments revealed that the roots have a maximum uptake capacity and high affinity for Cu. 相似文献
83.
ABSTRACT Elsholtzia splendens Naki has been identified as a copper (Cu) geobotanical indicator. In this study, the effects of Cu supply levels (control, 100, 200, 400, 600, 800, 1000, 1200 mg kg1) on the growth and Cu accumulation in E. splendens were studied in one pot experiment. The results showed that no reduction in shoot height and dry weight was noted when the plants were grown at Cu supply levels up to 1000 mg kg?1 in soil. Slight stimulation on shoot growth was noted at Cu levels ≥ 100 mg kg?1. Copper concentration in shoots and roots increased with increasing Cu levels, and reached a maximum of 1751 and 9.45 mg kg?1 (DW) at 1200 mg Cu kg?1. The amount of Cu accumulated in the roots and shoots were 313 and 22 μ g plant?1 at external Cu levels of 1000 and 800 mg kg?1, respectively. The shoot/root Cu ratios ranged from 0.005 to 0.008 and more than 92% of the total Cu taken up by E. splendens was accumulated in roots. Furthermore, Cu concentrations in roots and shoots were significant and positively correlated with total soil Cu, water, ammonium nitrate (NH4NO3), ammonium (NH4)-acetate, and ethylenediaminetetraacetic acid (EDTA) extractable Cu. These results indicate that E. splendens can considered as a Cu tolerant and accumulated plant, and root is the major part for accumulation of Cu in E. splendens. 相似文献
84.
《Communications in Soil Science and Plant Analysis》2012,43(15-20):2157-2170
Abstract A single biosolids application was made to 1.5×2.3 m confined plots of a Davidson clay loam (Rhodic Kandiudult) in 1984 at 0, 42, 84, 126, 168, and 210 Mg ha?1. The highest biosolids application supplied 750 and 600 kg ha?1 of Cu and Zn, respectively. Corn (Zea mays L.), from 1984 to 2000, and radish (Raphanus sativus L.) and romaine lettuce (Lactuca sativa var. longifolia), from 2001 to 2004, were grown at the site to assess heavy‐metal bioavailability. Extractable (0.005 diethylenetriamine (DTPA) and Mehlich 1) Cu and Zn were determined on 0 to 15‐cm depth samples from each plot. Corn yield increased with biosolids rate each year until 1993 to 1997, when yield decreased with biosolids rate because of phytotoxicity induced by low (<5.0) soil pH. The corn yield reduction was reversed between 1998 and 2000 upon raising the soil pH to approximately 6.0 by limestone addition following the 1997 season. Between 2001 and 2004, radish and lettuce yields were either not affected or slightly increased with biosolids rate, even as soil pH declined to below 5.5. Plant‐tissue metal concentrations increased with biosolids rate and as pH declined but were always within the normal range of these crops. Mehlich 1 and DTPA extractable metals increased linearly with biosolids rate. Extractability of Cu and Zn decreased approximately 50% over the past 20 years despite a decrease in soil organic matter concentration and greater than 95% conservation of the metals. 相似文献
85.
《Communications in Soil Science and Plant Analysis》2012,43(5):623-637
Manure nutrient analysis is an important component of nutrient‐management planning on dairy farms. The University of Vermont Agricultural and Environmental Testing Laboratory analyzed more than 2,300 dairy manure samples from 1992 to 2006. Means of nutrient content were consistent with published values, but variability among the sample results supports the need for laboratory analysis to determine manure application rates. Phosphorus (P) content of manure decreased by about 30% from 1992 to 2004, presumably reflecting a shift in dairy diets to avoid feeding excess P, but P content increased in the following 2 years. The copper (Cu) content of liquid manure increased four‐fold, mostly after 1998, a change attributed to increased use of copper sulfate (CuSO4) in foot baths. While not reliable for making nutrient‐management decisions on individual farms, long‐term summaries can be useful to detect trends and to put individual analytical results in context. 相似文献
86.
供试三中不同土壤溶解态胡敏酸(HA)与Cu^2+络合的稳定常数logK大小呈:黑垆土HA>娄土HA>黄绵土HA,logK的大小与pH、温度(T)及离了程度(1)有关;络合反应的热和学函数变化:标准自由能变ΔrGm^θ<0,标准焓变ΔrHm^θ<0,标准熵变ΔrSmθ<0,表明络合是自发的放热反应,体系有序性增大。ΔrHm^θ负值大小于logK呈相同次序,称为HA络合Cu^2+过程中HA分子变形及络 相似文献
87.
《Communications in Soil Science and Plant Analysis》2012,43(11):1091-1099
Abstract Cauliflower (Brassica oleracea Botrytis cv. Snow Crown) was grown in field microplots of an organic soil containing residual fertilizer Cu varying from 81 to 1063 ppm (w/w) as a result of three levels of Cu applications made in the previous two seasons. The variation in soil‐Cu was found to have no significant influence on the yield, nutrition or copper status of the crop. 相似文献
88.
《Communications in Soil Science and Plant Analysis》2012,43(1-2):82-95
Abstract A compost of high copper (Cu) and zinc (Zn) content was added to soil, and the growth of barley (Hordeum vulgare L.) was evaluated. Four treatments were established, based on the addition of increasing quantities of compost (0, 2, 5, and 10% w/w). Germination, plant growth, biomass production, and element [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), sodium (Na), magnesium (Mg), iron (Fe), Cu, manganese (Mn), and Zn] contents of soil and barley were determined following a 16‐week growing period. Following harvesting of the barley, analysis of the different mixtures of soil and compost was performed. Micronutrient contents in soils as affected by compost additions were determined with diethylene–triamine–pentaacetic acid (DTPA) (Cu, Mn, Fe, and Zn) or ammonium acetate [Ca, Na, Mg, K, cation exchange capacity (CEC)] extractions, and soils levels were compared to plant uptake where appropriate. Increasing rates of compost had no affect on Ca, Mg, or K concentration in barley. Levels of Cu, Zn, Mn, and Na, however, increased with compost application. High correlations were found for DTPA‐extractable Cu and Zn with barley head and shoot content and for Mn‐DTPA and shoot Mn content. Ammonium acetate–extractable Na was highly correlated with Na content in the shoot. High levels of electrical conductivity (EC), Cu, Zn, and Na may limit utilization of the compost. 相似文献
89.
[目的]研究防治黄颡鱼斜管虫和杯体虫病安全有效的药物、剂量及用法。[方法]对患有斜管虫和杯体虫病的黄颡鱼用硫酸铜、硫酸铜和硫酸亚铁合剂(5∶2)、硫酸锌、硫酸锌和聚维酮碘制剂、福尔马林和优马林6种药物在3个浓度下使用遍洒法进行正交叉试验,以确定安全有效地防治斜管虫和杯体虫病的药物及剂量。[结果]硫酸锌和聚维酮碘制剂对黄颡鱼斜管虫和杯体虫病的防治效果最好,优马林、硫酸硫酸锌次之,硫酸铜、硫酸铜与硫酸亚铁合剂、福尔马林的防治效果较差。[结论]治疗黄颡鱼斜管虫和杯体虫病的最佳药物是硫酸锌和聚维酮碘制剂,其用药浓度为:硫酸锌0.60 mg/L、聚维酮碘2.00 mg/L;优马林0.50 mg/L也是治疗黄颡鱼斜管虫和杯体虫病的有效药物。 相似文献
90.
以秦美猕猴桃茎段为外植体,诱导愈伤组织并进行猕猴桃再分化及生根试验。在分化培养基中分别添加不同浓度的铜离子进行筛选,以确定适于猕猴桃愈伤组织分化的最佳铜离子浓度。结果表明:再分化培养基中添加1.0 mg.L-1的铜离子时,可明显提高猕猴桃愈伤组织绿苗再分化率及生根率。但当铜离子浓度超过2.0 mg.L-1时,猕猴桃愈伤组织绿苗再分化率显著降低。 相似文献