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Crystallization and melting properties of triacylglycerols (TGs) in anhydrous goat's milk fat (AGMF) are investigated by X-ray diffraction as a function of temperature (XRDT) coupled with high-sensitivity differential scanning calorimetry (DSC), using synchrotron radiation and Microcalix. The polymorphic behavior of AGMF was monitored by varying the cooling rates between 5 and 1 degrees C/min from 45 to -20 degrees C with their subsequent melting at 1 degrees C/min. Quenching of AGMF at -20 degrees C was also examined to determine the metastable polymorphic form of AGMF. At intermediate cooling rates, TGs in AGMF crystallize, from about 18 degrees C in two different lamellar structures with triple chain length 3Lalpha stacking of 72 A and a double chain length 2Lalpha stacking of 48 A, which are correlated to two overlapped exothermic peaks recorded by DSC. A reversible transition sub alpha <--> alpha was observed. Subsequent heating at 1 degrees C/min shows numerous structural rearrangements before final melting. At fast cooling of AGMF (5 degrees C/min), similar unstable crystalline varieties are formed while three endotherms are recorded. Several new unstable lamellar structures are observed after quenching. All of these data are compared to those previously reported at slow cooling (0.1 degrees C/min) showing a relative stability of the structures formed. In spite of general similitude, the thermal and structural behavior of the goat's milk is more complex than that of the cow's milk.  相似文献   
3.
We characterized the effectiveness of Flavourzyme treatment in the hydrolysis of amide bonds in polyamide fabric by quantitating the ionic groups released into the treatment liquid and those formed on the fabric surface. On the basis of hydrolytic activity, we demonstrated that Flavourzyme effectively hydrolyzed amide bonds in polyamide (PA) fabric. The optimal treatment conditions were found to be pH 7.0, temperature 40 °C, treatment time 120 min, and Flavourzyme concentration 10 % based on weight of fiber. PA fabric treated with Flavourzyme exhibited increased numbers of amino and carboxyl groups, as evaluated by zeta potential and color strength. As the amounts of ionic groups formed by Flavourzyme hydrolysis increased, the water contact angle and water absorbency time decreased.  相似文献   
4.
In this study, we investigated the effects of enzymatic hydrolysis on polyamide fabrics by using bromelain as an enzyme. The hydrolytic activity of bromelain was evaluated on the basis of the number of carboxylic groups formed on the surface of the polyamide fabrics, and it was measured using the reactive dye absorbance. In addition, 2,4,6-trinitrobenzenesulfonic acid was added as an indicator to measure the number of amino groups released into the treatment liquid by the changes in color of the liquid. The optimum treatment conditions were bromelain pH of 6.0, treatment time of 120 min, temperature of 50 °C, concentration of 10 % (owf), and L-cysteine concentration of 70 mM. The weight loss in the fabric after treatment with bromelain facilitated by L-cysteine significantly improved; however, the tensile strengths of the polyamide fabrics did not show any differences. Bromelain hydrolysis of the polyamide fabrics thus improved hydrophilicity without damaging the fabrics’ strength.  相似文献   
5.
Neorogioltriol is a tricyclic brominated diterpenoid isolated from the organic extract of the red algae Laurencia glandulifera. In the present study, the anti-inflammatory effects of neorogioltriol were evaluated both in vivo using carrageenan-induced paw edema and in vitro on lipopolysaccharide (LPS)-treated Raw264.7 macrophages. The in vivo study demonstrated that the administration of 1 mg/kg of neorogioltriol resulted in the significant reduction of carregeenan-induced rat edema. In vitro, our results show that neorogioltriol treatment decreased the luciferase activity in LPS-stimulated Raw264.7 cells, stably transfected with the NF-κB-dependent luciferase reporter. This effect on NF-κB activation is not mediated through MAPK pathways. The inhibition of NF-κB activity correlates with decreased levels of LPS-induced tumor necrosis factor-alpha (TNFα) present in neorogioltriol treated supernatant cell culture. Further analyses indicated that this product also significantly inhibited the release of nitric oxide and the expression of cyclooxygenase-2 (COX-2) in LPS-stimulated Raw264.7 cells. These latter effects could only be observed for neorogioltriol concentrations below 62.5 μM. To our knowledge, this is the first report describing a molecule derived from Laurencia glandulifera with anti-inflammatory activity both in vivo and in vitro. The effect demonstrated in vitro may be explained by the inhibition of the LPS-induced NF-κB activation and TNFα production. NO release and COX-2 expression may reinforce this effect.  相似文献   
6.
The aim of this paper is to improve moisture regain of PET fabrics using a lipase treatment. Effects of nine lipase sources, lipase activator and nonionic surfactant on moisture regain of PET fabrics are examined. Moisture regains of lipase-treated samples improve by two times in average compared with untreated and buffer-treated samples. Alkaline treatment creates larger pitting by more aggressive attack into fiber which is proved by SEM and water contact angle measurement. Moisture regain by alkaline treatment (0.568 % ± 0.08) does not improve. However, lipase-treatment (L2 treatment) improves moisture regain up to 2.4 times (1.272 % ± 0.05). Although lipase treatment is more moderate than alkaline treatment, lipase hydrolysis on PET fabrics improves moisture regain, efficiently. K/S values improved confirm that carboxyl and hydroxyl groups are produced on the surface of PET fabrics by lipase hydrolysis. Moisture regain and dyeability improve by lipase hydrolysis on PET fabrics.  相似文献   
7.
ABSTRACT Two South African sandy soils, one suppressive and the other conducive to ectoparasitic nematode damage on monoculture sugarcane, were compared. Analysis of field transects indicated that the suppressive soil displayed a comparatively higher population of the weak ectoparasite Helicotylenchus dihystera, whose predominance among ectoparasitic nematodes is known to limit yield loss caused by more virulent phytonematodes. Soil type was identical at both sites (entisols), but the suppressive soil had a higher organic matter content and a lower pH, which correlated with H. dihystera population data. In contrast, microclimatic differences between the two field sites were unlikely to be responsible for the suppressive or conducive status of the soils, as shown in a greenhouse experiment. The two soils exhibited a bacterial community of the same size but with different genetic structures, as indicated by automated ribosomal intergenic spacer analysis (RISA). The number of culturable fluorescent pseudomonads was higher for the conducive soil, probably because extensive root damage caused by ectoparasitic nematodes favored proliferation of these bacteria. This study shows that apparently small differences in soil composition between fields located in the same climatic area and managed similarly can translate into contrasted nematode communities, ectoparasitic nematode damage levels, and sugarcane yields.  相似文献   
8.
The efficacy of fluorescent pseudomonads as suppressors of soil-borne diseases is linked to their ability to colonise plant roots. Monitoring the dynamics of biocontrol agents in the rhizosphere should improve the irreliability. We designed a pair of Sequenced Characterised Amplified Region (SCAR) primers specific to Pseudomonas fluorescens Pf29A, based on a specific 700 bp RAPD product selected in a previous work. Primer specificity was tested with DNA samples extracted from rhizospheric soil and rhizoplane of wheat plants grown in two different non-sterile soils. We assessed the total population of Pf29A by PCR and the culturable population by counting a tetracycline-resistant Pf29A transformant producing Green Fluorescent Protein (GFP), on selective medium 5 days after inoculation of non-sterile soil. SCAR primers were specific for Pf29A in both soils. We evaluated the limit of detection to 14.2 fg of target DNA, equivalent to 242 Pf29A cells per cm of wheat root. Culturable populations of Pf29A transformant accounted for 13% and 4% of the total populations 5 days after treatment with 103 and 107 CFU of transformed Pf29A per gram of soil. The SCAR derived sequence is a good candidate to develop a strain specific and sensitive PCR-quantification of Pf29A available for population dynamic studies in fields. We confirm that only a small proportion of the total Pf29A rhizosphere population is culturable.  相似文献   
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The synthesis of poly(norbornene ester)s by using a (η 3-substituted allyl) palladium (N-heterocyclic carbene (NHC)) complex as catalyst was performed and the relationship between chemical structure and glass transition temperature or refractive index of poly(norbornene ester)s was investigated. Norbornene ester monomers were synthesized via esterification of 5-norbornene-2-methyl alcohol and aromatic carboxylic acids. The polymerization catalyst, (η 3-substituted allyl) palladium (NHC) complex, was synthesized according to a published procedure. 1H-NMR spectroscopy was performed to determine chemical structure of monomers and polymers. The molecular weight of the polymers was measured via gel permeation chromatography and the thermal properties were analyzed via thermogravimetric analysis and dynamic mechanical analysis. Refractive indices of polymer films were measured using a prism coupler. Polymers with the highest M n (between 100 kg/mol and 300 kg/mol) were synthesized when the ratio of monomer to catalyst was 2000:1. The glass transition temperature of synthesized polymers was about 100 °C lower than that of conventional norbornene polymers. Among the six polymers of different chemical structures, four polymers exhibited a refractive index of 1.6 or more at a wavelength in the visible light region.  相似文献   
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