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61.
The aqueous extract of Phellodendron amurense Rupr.(Amur Cork Tree) provides a rich source of antioxidants and chemical compounds, and can be used for food and wood preservative materials.In this study, we characterized the chemical composition of this extract by GC and GC/MS.The antioxidant capacity was evaluated using a variety of antioxidant assays(superoxide radical,hydroxyl radical, nitric oxide radical, and DPPH radical scavenging activity).Additionally, total polyphenolic content was determined.Phenolic acids and acetone derivatives were major compounds of the extract capable of scavenging the DPPH free radical and reducing ferric ions.DPPH and ferric ion reduction results were strongly correlated with total phenolic content of the extract which also exhibited strong nitric oxide, hydroxyl radical scavenging and superoxide anion radical scavenging activities.  相似文献   
62.
Owing to increased tolerance and the development of resistance in stored product insects to the fumigant phosphine, in recent years there has been a shift in the target terminal concentration from 100 ppm (100 mL m(-3)) to a higher level of 1000 ppm to achieve 100% insect mortality in 7 day commodity treatments. Therefore, there is a need to investigate whether the revised target concentration could be achieved for food commodities fumigated with phosphine at the standard dose of 2 g m(-3) for 7 days under airtight conditions at > or = 25 degrees C. When different types of food commodity (total 74) were fumigated (300 g per replicate) with phosphine at 2 g m(-3) for 7 days, the terminal gas concentrations in the free space of the commodities varied from 0 to > 2000 ppm. In chambers containing no substrate, a 1417 ppm concentration was recorded. Paddy rice, most of the oilseeds, shelled tree nuts, butter beans, cardamom, green gram splits, coriander powder, rice bran and cocoa powder were more sorptive (> or =60%), such that the target concentration of 1000 ppm was not achieved at the end of 7 days. For these commodities, increased doses of 3-6 g m(-3) were required to attain 1000 ppm. In-shell almonds, green cardamom, in-shell peanuts, leaf tea, tamarind pulp and sunflower seeds were exceptionally sorptive (>90%), so that 0, 41, 112, 168, 203 and 217 ppm respectively were noted at the end of 7 days; the dose must exceed 6 g m(-3) for effective fumigation of these commodities.  相似文献   
63.
The interaction of antiperoxidative flavonoids artocarpin (AR), cycloartocarpin (CAR), dalspinin (DP), dalspinosin (DPO), and dalspinin-7-O-galactoside (DPG) with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS(.+)) and O2(-.) was studied in phosphate buffer (pH 7.4). The ability of these compounds to inhibit lipid peroxidation and DNA scission was also investigated. The radical scavenging efficiency of flavonoids is demonstrated by the reduction of nitrogen-centered radical cation (ABTS(.+)). The reduction of ABTS(.+) follows the order quercetin > morin > Trolox > AR > DPO > CAR > DP. Inhibition of lipid peroxidation was studied by following Mb(IV) reduction, induced by lipid, arachidonic acid. These results are compared with those obtained for well-known antioxidants such as quercetin, morin, and Trolox. The structure-activity relationships between chemical structures of the flavonoids and their radical scavenging activities are anlayzed. The scavenging of O2(-.), inhibition of lipid peroxidation, and DNA damage depend on the oxidation potential of the flavonoids. The possible mechanism for radical scavenging activities of flavonoids in relation to their structure is also outlined.  相似文献   
64.
With the establishment of advanced technology facilities for high throughput plant phenotyping, the problem of estimating plant biomass of individual plants from their two dimensional images is becoming increasingly important. The approach predominantly cited in literature is to estimate the biomass of a plant as a linear function of the projected shoot area of plants in the images. However, the estimation error from this model, which is solely a function of projected shoot area, is large, prohibiting accurate estimation of the biomass of plants, particularly for the salt-stressed plants. In this paper, we propose a method based on plant specific weight for improving the accuracy of the linear model and reducing the estimation bias (the difference between actual shoot dry weight and the value of the shoot dry weight estimated with a predictive model). For the proposed method in this study, we modeled the plant shoot dry weight as a function of plant area and plant age. The data used for developing our model and comparing the results with the linear model were collected from a completely randomized block design experiment. A total of 320 plants from two bread wheat varieties were grown in a supported hydroponics system in a greenhouse. The plants were exposed to two levels of hydroponic salt treatments (NaCl at 0 and 100 mM) for 6 weeks. Five harvests were carried out. Each time 64 randomly selected plants were imaged and then harvested to measure the shoot fresh weight and shoot dry weight. The results of statistical analysis showed that with our proposed method, most of the observed variance can be explained, and moreover only a small difference between actual and estimated shoot dry weight was obtained. The low estimation bias indicates that our proposed method can be used to estimate biomass of individual plants regardless of what variety the plant is and what salt treatment has been applied. We validated this model on an independent set of barley data. The technique presented in this paper may extend to other plants and types of stresses.  相似文献   
65.
66.
Veterinary Research Communications - Livestock plays a significant role in the socio-economic development of developing countries by providing livelihood and nutritional security, transport,...  相似文献   
67.
A field experiment involving 10 sweet sorghum cultivars was undertaken to study the effect of panicle removal at anthesis on juice quality characteristics and sugar yield in sweet sorghum; control plants were left intact. The plants were harvested at grain maturity, and juice extracted from the millable stalk was analysed for sucrose contact (Pol percentage), brix and purity. Deheading treatment resulted in significant increases in millable stalk and sugar yields over those of the intact control plants. As a result of panicle removal, stem dry matter accumulation increased and side tillers were generated. The amount of juice extracted increased in the treated plants, but sucrose (Pol percentage), brix and purity levels in the juice were reduced in comparison with the intact plants.  相似文献   
68.
A severe outbreak of leaf blight was observed in noni crop for the first time in Tamil Nadu and Karnataka states of India during 2008–2009. Based on pathogenicity, morphology and ribosomal DNA spacer sequences, the pathogen was identified as Alternaria alternata (Fr.) Keissler. This report is the first of Alternaria leaf blight of noni.  相似文献   
69.
70.
About 4 different predominant adapted fungal strains (screened from effluent sample) Aspergillus sp., Penicillium sp., Fusarium sp. and Mucor sp. and 4 predominant non-adapted strains (screened from soil, water and fungal fruiting bodies) Aspergillus sp., Penicillium sp., Fusarium sp. and Rhizopus sp., with potential dye decolorization ability on Reactive black 5, Amido black-10B, Red 5B, Reactive red 120 and Anthraquinone violet R were isolated. These organisms were used to develop a consortium which was used in analyzing the bioremediation efficiency on textile effluents containing a mixture of azo dyes. There was about 67% of reduction in color along with 34% of COD reduction by non-adapted fungal consortium while effective bioremediation efficiency was observed in adapted fungal consortium (Color 75% and COD 50%). The regression co-efficient for Langmuir and Freundlich adsorption isotherms were found to be higher for adapted fungal consortium (R2 = 0.97 and R2 = 0.92) than the non-adapted consortium (R2 = 0.97 and R2 = 0.85) proving that both monolayer and multilayer adsorption of dyes were observed on treating the samples with the adapted fungal consortium. On analyzing the results observed through chi-square test, the calculated value (28.712) was higher than the tabulated value (9.49) at a 4 degree freedom hence the hypothesis was rejected. So, there was an association between adapted fungal consortium and non-adapted fungal consortium and hence the adapted fungal consortium could be considered potentially useful for the bioremediation of textile effluent.  相似文献   
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