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101.
利用海带中富含碘、钙的特点,开发了一种以海带粉、高筋面粉、枧水为原料制作的高碘海带煮面。通过正交试验得出最优配方为:高筋面粉50%,海带粉2%,枧水0.6%,水30%。同时对海带煮面生产工艺中关键步骤糊化处理的水煮时间与热蒸时间进行研究,发现水煮2min、热蒸6min的产品外观及适口性最佳。产品营养分析表明,该海带煮面营养丰富,富含维生素与微量元素,尤其碘的含量高,能满足人们日常饮食中对碘的需求。  相似文献   
102.
电子束辐照对大米营养和蒸煮品质的影响   总被引:1,自引:1,他引:1  
为进一步发展、完善辐照杀虫灭菌技术应用于储粮方面的理论研究,该研究采用0、0.83、1.56、2.30、4.93kGy不同剂量的电子束辐照大米样品,考察其对大米品质的影响。结果表明:不同剂量的电子束辐照对大米的蛋白质含量、氨基酸的含量与组成无明显影响(p>0.05);随着辐照剂量的增加,大米的脂肪酸值、胶稠度升高(p<0.05),吸水率、膨胀率下降(p<0.05);电子束辐照对大米糊化温度的影响不明显(p>0.05),但显著降低大米的峰值黏度、衰减值、回生值(p<0.05),明显影响米饭的蒸煮品质(p<0.05),剂量为4.93kGy时蒸煮米饭出现明显的褐变。电子束辐照大米的剂量不宜超过2.30kGy,以0.83kGy的辐照剂量较佳,该研究结果将为储藏和进出口检疫中对大米进行辐照杀虫、灭菌时的剂量选择提供参考。  相似文献   
103.
刺参冻干加工技术研究   总被引:4,自引:0,他引:4  
研究了刺参的冻干加工技术。结果表明,采用三种方法加工三组(500g/组)活刺参,成品中蛋白质分别为:盐渍干参33.64g,含量17.71%;活性刺参46、20g,含量83.24%;免发刺参41、14g,含量82、28%;合理运用冻干技术不但能有效保全刺参的活性、营养成分,而且食用便利、外形美观。  相似文献   
104.
通过在石岩寨林场666.67hm^2华山松林中选取29块样地,实测9组不同径阶树高、冠幅及枝下高数据,利用营养面积技术,建立树冠面积与立木胸径的回归方程,确定不同径阶应保留的标准密度,间伐强度蓄积为40.1%,间伐强度株数为39.98%,间伐蓄积为51359m^3,出材量32330m3。  相似文献   
105.
The nutrient status of Norway spruce in pure and in mixed-species stands   总被引:1,自引:0,他引:1  
Atmospheric deposition of N and S appears to have caused nutrient imbalance in Norway spruce stands in southern Sweden. This calls for a change of forest management to procedures that promote nutrient balance. Studies have shown lower soil acidity in Norway spruce/deciduous mixed stands than in spruce monocultures, but the tree nutrient status in such mixtures has not been much investigated so far.

The nutrient status of Norway spruce foliage and top mineral soil chemistry in monocultures and in stands mixed with beech, birch, or oak was investigated through paired comparisons on 30 sites in southern Sweden (27 sites) and eastern Denmark (three sites). In total, 45 mixed stands and 34 pure stands were included in the study.

Spruce needles from mixed stands had higher concentrations and ratios to N of K, P, and Zn than needles from pure spruce stands. Among the mixed stands, the K status appeared to be positively correlated with the percentage of deciduous tree basal area. Soil samples from mixed stands had a higher Mg concentration, base saturation, and BC/Al ratio than soil samples from pure stands. The spruce needle nutrient status was comparable in pure stands on fertile sites and in mixed stands on poor sites. We did not detect any differences in spruce tree growth between pure and mixed stands.

This paper discusses possible reasons for a positive effect on the tree nutrient status in mixed-species stands and the possibility of using mixed-species stands as a forest management procedure to avoid nutrient imbalance.  相似文献   

106.
套袋栽培对高节竹笋品质的影响   总被引:2,自引:0,他引:2  
选择生长良好、均匀的高节竹林作为样地,在出笋高峰期标记即将出土的竹笋320株,其中160株用0.3mm厚(共3层,每层0.1mm)的黑色塑料袋遮光,另160株作为对照。随着竹笋的生长,依次从遮光笋及对照笋中采收地上部分高度接近5、10、15、20、25、30、35cm的笋,待预处理后作为样品进行营养成分的分析。结果表明,在竹笋地上部分高度10~30cm范围内,套袋能降低竹笋中单宁、维生素C、粗蛋白的含量;套袋栽培的竹笋中粗纤维含量比自然生长的竹笋中的粗纤维含量约低10%以上,氨基酸总量也高于自然生长的竹笋。  相似文献   
107.
水培法磷矿石对小麦生长的影响   总被引:1,自引:0,他引:1  
Screening cultivars to grow under conditions of low phosphorus (P) availability and utilize P efficiently from compounds of low solubility in soils may be beneficial to overcome poor plant growth in P-deficient soils.The growth behavior and P utilization efficiency of seven wheat cultivars grown in hydroponics were studied,using rock phosphate as P source.The wheat cultivars grown for 30 days were significantly different in biomass accumulation,P uptake and P utilization efficiency.The dry matter production of all the cultivars was significantly correlated with P uptake,which in turn correlated to the drop in the root medium pH.The ranking of wheat cultivars on the basis of dry matter yield,P uptake and P utilization efficiency was Zamindar 80 > Yccora > C 271 > WL 711 > Barani 83 > PARI 73 > Rohtas.The cultivar Zamindar 80 appeared to possess the best growth potential in P-deficient soils.  相似文献   
108.
To determine the effect of boron (B) deficiency on biomass, reproductive yield, metabolism, and alterations in seed reserves of chickpea (Cicer arietinum L.) cv. ‘13.G‐256,’ plants were grown in refined sand until maturity at deficient (0.033 mg L?1) and adequate (0.33 mg L?1) B, supplied as boric acid (H3BO3). Boron‐deficient plants exhibited visible deficiency symptoms in addition to reduced number of pods and seeds, resulting in lowered biomass and economic yield. Boron deficiency lowered the concentration of B in leaves and seeds, photosynthetic pigments (leaves), Hill reaction activity, starch (in leaves and seeds), and proteins and protein N (in seeds), whereas phenols, sugars (in leaves and seeds), and nonprotein N (in seeds) were elevated. Specific activity of peroxidase (POX) increased in leaves and pod wall and decreased in seeds, while activity of acid phosphate and ribonuclease were stimulated in leaves, seeds, and pod wall in B‐deficient chickpea.  相似文献   
109.
Brazil is the largest producer of oranges (Citrus sinensis) in the world. The nutrient management of tree orchards is designed from experiments with a limited number of varieties. This knowledge is transferred to other varieties by diagnosing tissue nutrient composition and tree demand. Compositional data analysis has been first applied to tissue analysis of agricultural crops using centered log ratios with compositional nutrient diagnosis (CND-clr). The isometric log ratio (ilr) transformation is a new approach based on binary nutrient ratios and the principle of orthogonality (CND-ilr). We analyzed eleven nutrients: nitrogen (N), sulfur (S), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), boron (B), copper (Cu), zinc (Zn), manganese (Mn), and iron (Fe) in leaf tissue samples across 108 commercial plots (thirty-one grow Valencia, twenty-two Hamlim, twenty Pera, and thirty-five Natal). Nutrients were partitioned between macro- and micronutrients as well as anionic and cationic species. The effect size of varieties over Valencia was quantified by the mean and standard deviation of ilr values across ilr coordinates. Specific varietal nutrient profiles and ilr norms were defined. The nutrient profile of orange varieties could be classified into homogeneous groups to take advantage of fertilizer trials conducted on varieties of the same group. The Aitchison distance and a perturbation vector could be instrumental for diagnostic purposes and nutrient management.  相似文献   
110.
Abstract

Extracts that are coloured, owing to dissolved organic matter, give rise to an interference when boron is determined by the colorimetric Azomethine‐H method. A scheme is presented in which boron is removed from coloured extracts by dialysis. In this way the interference can be removed automatically. The suggested scheme allows hydroponic solutions and extracts of soils, peat‐based composts and plant materials to be analysed without further treatment at a rate of 20 hr‐1. The limit of detection is 0.05ppm B in solution. Recoveries of boron added to extracts from all types of sample were excellent. The effects of some interferences were investigated and found not to be significant under normal working.  相似文献   
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