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151.
Crude dihydroxystearic acid was prepared from palm based oleic acid and was then solvent purified with isopropyl alcohol in a custom fabricated simultaneous batch crystallizer unit. The crystallized dihydroxystearic acid was a functional ingredient that acted as multipurpose intermediate for synthesis of various fine chemicals, cosmetics and personal care products. The effects of solvent quantity and concentration on particle size distribution, crystal habit and morphology, and resultant crystal purity were studied. The crystals were purer but smaller and the span of the distribution curve was wider at higher solvent quantity and concentration. Through scanning electron microscopy and X-ray diffraction, it was observed that the crystals agglomerated into plate-like (flaky) habit with triclinic crystal structure. Solvent crystallization with 80% IPA at 20 °C and solute:solvent ratio of 1.0:1.0 was the most optimized and efficient, producing β-DHSA crystals that has high resistance against fat exudation during vacuum filtration process.  相似文献   
152.
Bisphenol A (BPA) and reactive black 5 (RB5) dye are among the most persistent and non-biodegradable contaminants in water which require an urgent need for the development of effective removal method. The ubiquitous existence of both contaminants could interfere with the human health and aquatic environmental balance. Photocatalytic process as one of advanced oxidation processes (AOPs) has shown high performance for degradation of organic compounds to the harmless materials under sensible condition. Therefore, this study aims to develop a visible-light-driven photocatalyst that can efficiently degrade BPA and RB5 present in household water. N-doped TiO2 were successfully synthesized via simple and direct sol–gel method. The prepared TiO2 nanoparticles were characterized by field emission scanning microscope (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and Brunauere Emmette Teller (BET) analysis. The incorporation of nitrogen in TiO2 lattice exhibited excellent optical responses to visible region as revealed by UV–Vis–NIR spectroscopy absorption capability at 400–600 nm. The photocatalytic activity of the N-doped TiO2 nanoparticles was measured by photocatalytic degradation of BPA and RB5 in an aqueous solution under visible-light irradiations. Degradation of BPA and RB5 was 91.3% and 89.1%, respectively after 360 min illumination. The degradation of BPA and RB5 by N-doped TiO2 was increased up to 89.8% and 88.4%, respectively under visible-light irradiation as compared to commercial TiO2 P25. This finding clearly shows that N-doped TiO2 exhibits excellent photocatalytic degradation of BPA and RB5 under visible irradiation, hence have a promising potential in removing various recalcitrant contaminants for water treatment to fulfill the public need to consume clean water.
Graphical Abstract ?
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153.
18 soybean genotypes were examined to investigate the relationships between some principal attributions of morphology with seed yield per soybean, by Random Complete Block Design (RCBD) study. This study was also carried out three replicates to gain reliable results. The results of variance analysis indicated that, there were significance differences among all soybean genotypes. Moreover, the results of correlated analysis revealed that biological yield (0.96), harvest index (0.92), and number of branches (0.92) had the uttermost correlation with seed yield. To data factor analysis, four independent variables justified 99 percent of all data. The first variable, seed yield, justified 96 percent of entire variance. Multiple-Regression Model with method Analytical Regression Model (step-by-step) was utilized to examine soybean seed yield. This model proved that biological yield, thousand seed weight, and harvest index entered into model respectively and justified 98.85 percent of variation of seed yield. Correlated coefficients of considered attributions were equal to 0.96, 0.78, and 0.92, respectively. All of these indexes had significant at 1% in statistical process. Therefore, these traits can be notability used in soybean breeding programs. Also, accordance to cluster analysis, the sample was divided into three groups.  相似文献   
154.
Vegetables are vital to the human diet, and in particular provide the well-known nutrients to maintain normal physiological functions. The prolonged application of large amount of fertilizers and pesticides has resulted in heavy metal accumulation in vegetable gardens. Exposure to heavy metals by the consumption of contaminated vegetables and its toxicity is a serious concern. This article reviews the presence of heavy metals in different vegetables, their mechanism of absorption, impact of heavy metals on physiology, and nutrient reduction and associated impact on humans with emphasis on pregnant women based on the existing scientific literature. However, a limited number of studies was found in the data base that examined the reduction of nutrients in the vegetables due to heavy metal contamination. The heavy metals were found in 36 vegetables in 61 regions of the world and were above permissible limits in most of the vegetables. Specific study to human toxicity due to the contamination of heavy metals may be conducted with emphasis on pregnant women, children, and elderly people. Furthermore, strategy and policy should be devised to control the heavy metals in vegetables and those vegetables that are hyper-accumulators of heavy metals should be identified for awareness purposes.  相似文献   
155.
A phytoplasma-associated disease was identified in Brassica campestris (sarson) plants during a survey conducted in Punjab province of Pakistan in 2014–2016. The symptomatic plants showed characteristic symptoms of phyllody and witches’ broom. Phytoplasma presence was detected by polymerase chain reaction on 16S ribosomal and tuf DNAs, followed by RFLP analysis and sequence comparison of the 16S rRNA and tuf genes. The phytoplasma detected was classified in a new ribosomal subgroup designed 16SrIX-H. The phytoplasma presence in phloem tissues of symptomatic sarson samples was also confirmed through light microscopy and transmission studies to healthy plants through dodder and the leafhopper Orosius albicinctus. This is the first report of identification of 16SrIX-H subgroup phytoplasma associated with sarson and its natural vector in Pakistan.  相似文献   
156.
Cellulolytic bacteria have a bio-activating role in the composting process. A study was carried out to isolate and identify cellulolytic bacteria from various sources. The isolates were cultured in the carboxymethyl cellulose (CMC) agar medium and incubated at 30°C for 3–7 days. Based on morphological characteristics of the isolates, maximum diameter of a clear zone around the colony and maximum cellulolytic activity, eight isolate were selected for further studies regarding composting experiments.

Molecular tests based on PCR amplification and sequencing of 16S rRNA gene of isolates showed the closest phylogenetic similarity with the species of Stenotrophomonas rhizophila DSM14405 (99.8%), Brevibacterium halotolerans DSM8802 (99.6%), Achromobacter marplatensis B2 (99.8%), Bacillus methylotrophicus CBMB205 (100%), Pseudomonas azotoformans IAM 1603 (99.7%), Bacillus sonorensis NBRC 101234 (99.8%), Bacillus subtilis KCTC 13429 (100%) and Ochrobactrum thiophenivorans DSM 7216 (99.3%). The study of the isolates impact on the composting of palm wastes in a randomized complete block design with 11 treatments in 3 replications showed that strain IB (B. methylotrophicus) caused a significant decrease in C:N ratio (58%). The increasing of microbial respiration compared with control after 30 days incubation at 37°C showed that the B. methylotrophicus strain IB with cellulolytic characteristics can be applied to hydrolysis of cellulosic biomass in the composting processes.  相似文献   

157.
To investigate the effect of applying 15N-labeled ammonium sulfate with or without a nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) on fertilizer use efficiency and crop productivity of different wheat genotypes, a field trial was conducted at the Nuclear Agricultural Department’s farm of Iran in 2013–2014. The treatments included five wheat genotypes with different 13 C isotope discrimination and three fertilizer treatments, an unfertilized control, 15N-labeled ammonium sulfate, and 15N-labeled ammonium sulfate with DMPP in three replications. Soil samples were taken after 2, 4, and 6 weeks after sowing and also at harvest time. Results from 15N experiment showed that DMPP delayed nitrification of ammonium for 42 days. Genotypes with lower discrimination index had greater uptake of ammonium ions which led to increase crop yield and nitrogen fertilizer use efficiency. The results also suggested that the use of DMPP may not be beneficial in some fast growing wheat genotypes.  相似文献   
158.
159.
Animal rearing is the major occupation of most population of South Asian countries. Due to lack of resources and limited approach to modern medicine, most of the livestock raisers prefer to use plant-based traditional medicine also referred to as ethnoveterinary medicine (EVM). Indeed, the use of medicinal plants in South Asia dates back to several centuries with documented evidences. However, there is currently a dearth of documentation and compilation of use of medicinal plants for animal diseases in this part of the world. This review aims to provide an up-to-date compilation of common medicinal plants used for the treatment and/or management of common animal diseases in South Asian countries. Extensive literature search was conducted online and relevant data was retrieved from well-known scientific databases. A total of 276 plants belonging to 95 families have been documented to be in common use for managing 14 different categories of animal diseases. Solanaceae, Lamiaceae, Fabaceae, and Leguminosae were most common plant families in terms of their plant species used for EVM. Gastric diseases were commonly reported and accounted for 72 species of plants used for its treatment followed by the miscellaneous disorders category and skin diseases comprising of 65 and 39 plant species respectively. Herbs accounted for 46% of the total plant species, followed by trees (33%), and shrubs (18%). The EVM were applied through different routes of administration; oral administration accounted for 72% followed by topical application 27%, while burning of plant parts to create smoke around animals to repel insects was less common (1%). It is anticipated that the present review will stimulate further ethnoveterinary research among livestock disease management practices in South Asia.  相似文献   
160.
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