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801.
建立了硫酸新霉素可溶性粉中非法添加7种抗寄生虫药物的HPLC-PDA检测方法。采用十八烷基键合硅胶为填充剂;以水-乙腈为流动相,梯度洗脱,流速1.0 mL/min;二极管阵列检测器,波长为245 nm。通过液相色谱保留时间、峰纯度检查和光谱相似度检查对非法添加物进行确证。结果表明,该色谱条件下,7种抗寄生虫药物间分离度良好,在3~80μg/mL浓度范围内线性关系良好(R2>0.9998),回收率在103.9%~105.8%之间,RSD≤2.5%,4种苯并咪唑类和3种大环内酯类的检测限分别为0.05 g/kg和0.3 g/kg。该方法操作简便、快速、灵敏度高,可用于硫酸新霉素可溶性粉中非法添加抗寄生虫药物的测定。 相似文献
802.
Retention behavior of size and aluminum components in handsheets prepared in rosin soap size-alum systems 总被引:2,自引:0,他引:2
Handsheets were prepared with rosin soap size and aluminum sulfate under various conditions, and the retention behavior of the rosin size and aluminum components in the handsheets was studied. Pyrolysis-gas chromatography and X-ray fluorescence analysis were used to determine the size and aluminum contents in the handsheets, respectively. When the addition level of rosin soap size varied from 0% to 4% and that of aluminum sulfate was fixed at 2%, the rosin size content increased with the increase in the size addition level, whereas aluminum and calcium contents were roughly constant. Under these conditions, handsheets prepared from fines-free pulp had aluminum contents less than those for the original beaten pulp, probably because the former pulp had a carboxyl content less than that of the latter pulp. Not only the conventional rosin retention mechanism but also mechanism proposed below must exist in the rosin soap size-alum systems. That is, some aluminum compounds originating from aluminum sulfate are adsorbed on pulp fibers immediately after the aluminum sulfate addition. These adsorbed aluminum compounds form cationic sites on pulp fibers, and free rosin acid components with anionic charges are then adsorbed onto the cationic sites of pulp fibers at the wet-end.This research was presented in part at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 1996 相似文献
803.
804.
Abstract. Inputs and outputs of sulphur (S) were quantified over a three year period using field lysimeters containing undisturbed 60 cm deep soil monoliths of a sandy loam. There were four treatments, including a control (no S) and three forms of sulphur fertilizers: ammonium sulphate (AS); micronized elemental sulphur (MS0); and bentonite clay and elemental sulphur mixture (BS0). Sulphur was applied at the beginning of the experiment in autumn at 50 kg ha–1. Atmospheric deposition varied between 6.7 and 7.8 kg S ha–1 yr–1. Leaching losses of S ranged from 35 kg ha–1 in the control to 83 kg ha–1 in the AS treatment over three years, with dissolved organic S accounting for 6–10% of the S leached. In the first year, 7, 26 and 72% of the applied S was lost to drainage water in the BS0, MS0 and AS treatments, respectively, and the percentages increased to 33, 75 and 96% by the end of year 3. No significant differences in sulphur uptake by herbage were found in any of the harvests except a significant increase in the BS0 treatment in the second cut of the second year. Over three years, total S outputs exceeded total S inputs in all treatments, with the control and the AS treatments showing a larger S deficit (34–35 kg ha–1) than the MS0 (23 kg ha–1) and BS0 (7 kg ha–1) treatments. The deficits indicate a depletion of soil S, probably through net mineralization of organic S. The results confirm that sulphate was highly mobile and prone to leaching under the experimental conditions, whereas the slow release characteristics of elemental S, particularly BS0, led to smaller leaching losses and larger residual values. 相似文献
805.
Abstract. A database of 1065 fields in all parts of Finland, two soil profiles (augerhole borings) per field, was screened for acid sulfate (a.s.) soils. Each field represented 2100 14;ha of cultivated land. Soil pH and redox potential were determined in the field, at intervals of 10 14;cm, to a depth of 200 14;cm. Of the maximum of 124 profiles considered as a.s. soils according to the Soil Taxonomy and ILRI (International Institute of Land Reclamation and Improvement) systems, 46 profiles exhibited pH <3.5. These represented 48 14;000 14;ha of land. More than half of these severely acidic soils were associated with reduced subsoils and probably contained actively oxidizing sulfidic materials within 150 14;cm of the soil surface, while the remaining profiles were oxidized at least down to 150 14;cm. Using Soil Taxonomy criteria, the total area of cultivated a.s. soils was 67 14;000–130 14;000 14;ha. The minimum estimates exclude soils that may be leached or too low in sulfide to meet the criteria of a.s. soils. Application of the ILRI system produced an estimate of 61 14;000–130 14;000 14;ha. In the maximum estimate, 27% of the profiles were raw, 61% ripe and 12% potential a.s. soils. According to the FAO/UNESCO system, the area of cultivated a.s. soils (pH <3.5 or assumed sulfidic materials) is considerably less: 43 14;000–78 14;000 14;ha. All these estimates are only a fraction of the area considered to be covered by a.s. soils by established Finnish criteria. The choice of estimate has important economic implications for liming subsidies and planning regulations for the drainage of a.s. soils. 相似文献
806.
The use of ecofriendly biodegradable controlled-release formulations of mosquito larvicides could reduce the frequency of application and losses due to degradation of the insecticide compared with conventional formulations. Among the 20 matrices developed by entrapping the organophosphorus mosquito larvicide, fenthion, in carboxymethylcellulose ionotropically cross-linked with aluminium ions which were studied for release profiles, two matrices, CRF3b and CRF5b, were found to be stable for 16 and 14 weeks under simulated field conditions. The average concentration of fenthion released per week ranged from 0.06 to 3.5 mg litre(-1) for CRF3b and 0.09 to 2.72 mg litre(-1) for CRF5b. Of these two formulations, CRF3b was the more stable, maintaining the concentration of the active ingredient at the level required to effect mosquito control. The cumulative release of fenthion per pellet was 80% from CRF3b and 72% from CRF5b. Based on the study with fenthion, two similar matrices for triflumuron, a benzoylphenylurea insect growth regulator, STAR3b and STAR5b were developed. These matrices were stable up to 16 weeks with the average concentration of triflumuron released per week ranging from 0.05 to 3.44 mg litre(-1) for STAR3b and 0.07 to 2.71 mg litre(-1) for STARSb. The cumulative release of triflumuron per pellet was 75% from STAR3b and 76% from STAR5b. From the results of this study under simulated conditions, it is estimated that the application of four pellets of either fenthion or triflumuron per square metre of the breeding surface may play a useful role in controlling Culex quinquefasciatus Say in larval habitats for about 4 months. 相似文献
807.
使用硫酸铜作为铜源,在生长猪饲料中添加铜,对照组铜添加浓度为0mg/kg,试验各组铜添加浓度为100mg/kg、150mg/kg、200mg/kg、250mg/kg和300mg/kg。试验开始时采血,之后每隔20d采血一次。测定有关血液生化指标。试验结果如下:试验组平均血清尿素氮(SUN)在20、40、60和80d时,分别降低10.3%、12.0%、9.7%和5.6%;60d时200mg/kg和250mg/kg铜组降幅分别达8.7%(P<0.01)和8.4%(P<0.05)。总蛋白(TP)和白蛋白(ALB)试验组比对照组均有不同程度提高,TP在40、60和80d时分别提高5.4%、7.2%和3.2%;ALB在20、40、60和80d时分别提高14.6%、15.5%、16.9%和0.23%。甘油三脂(TG3)、胆固醇(CH)、采食量未见有显著性变化(P>0.05)。本试验结果表明:日粮铜水平对血液相关生化指标的影响随饲料铜浓度的差异呈现明显的阶段性差异,其差异的显著性与铜的促生长效应基本是一致的。 相似文献
808.
809.
Depletion of the residues of colistin and amoxicillin in Turkeys following simultaneous subcutaneous administration 总被引:1,自引:0,他引:1
L. Tomasi L. Giovannetti A. Rondolotti G. Della Rocca G. L. Stracciari 《Veterinary research communications》1996,20(2):175-182
The tissue distribution and depletion of colistin and amoxicillin were studied in 84 turkeys dosed subcutaneously on 4 consecutive days with a formulation containing the two drugs at 0.2 ml/kg per day, corresponding to 50 000 IU of colistin sulphate/kg and 20 mg of amoxicillin trihydrate/kg. All the turkeys were killed 1–30 days after the final dose and samples of muscle, liver, kidney and cutaneous-subcutaneous tissues and of the injection site were taken for analysis for colistin and amoxicillin residues. The colistin concentrations in the liver (117.5±26.0 ng/g) and cutaneous-subcutaneous tissue (100.0±35.6 ng/g) were higher than those in kidney (92.0±34.4 ng/g) or muscle (67.5±16.9 ng/g) 1 day after the final dose. The concentration of this drug then increased for 9–14 days, followed by a slow decrease. The antibiotic was still present at low concentrations in the kidneys of all the treated birds and in the livers of two turkeys 30 days after the end of treatment. Amoxicillin concentrations were greatest in muscle (389.2±195.0 ng/g) and at the injection sites (440.3±213.9 ng/g) 1 day after treatment ceased, with a subsequent rapid decline. This drug was undetectable in the livers and kidneys by 10 days after dosing ceased.Abbreviations IU
international units
- i.v.
intravenous 相似文献
810.
选用4头体重420 kg、年龄2.5岁、装有永久性瘤胃瘘管的西门塔尔牛阉牛,采用4×4拉丁方设计,对照组饲喂基础日粮,处理组在基础日粮基础上添加硫酸铜,处理1,2和3组分别加硫酸铜31,62和93 mg/kg,研究硫酸铜对瘤胃发酵和尿嘌呤衍生物的影响。结果表明,瘤胃液pH值和挥发性脂肪酸浓度无显著差异(P>0.05);93mg/kg组氨态氮浓度显著升高,而乙酸/丙酸显著降低(P<0.05)。93 mg/kg组玉米秸秆和豆粕瘤胃有效降解率显著降低(P<0.05),尿酸无显著变化。93 mg/kg组尿囊素、尿嘌呤衍生物和微生物蛋白质显著低于对照和31mg/kg组(P<0.05)。表明添加93 mg/kg的硫酸铜影响瘤胃发酵,以硫酸铜为铜源时添加量以31~62 mg/kg为宜。 相似文献