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41.
In this study, the effect of corona discharge treatment on the physical and mechanical properties of bleached cotton and polyester-cotton fabrics were investigated. For this purpose, the samples were treated by corona discharge at two levels of voltage 5 and 10 kV, and at various duration times of plasma, ca. 1.4, 2.1 and 3.5 min. The corona discharge treatment was applied on the fabric samples before and after bleaching treatment. The results show that the corona influences on the surface morphology, breaking strength, air permeability, abrasion resistance, and pilling of cotton and polyester-cotton fabrics. Moreover, the levels of voltage and duration of plasma have a different effect on the properties of fabrics.  相似文献   
42.
The objective of the present study was to evaluate the effect of breed of stallion and individual stallion on secondary sex ratio (SSR; the proportion of male foals at birth). Data associated with the sex of foals and the sire, as well as the breed and age of sire were retrieved from the database of the Equestrian Federation of the Islamic Republic of Iran. In total, data consisted of 4,491 birth records from 92 stallions. Stallions were from three breeds of Arabian, Thoroughbred, and Akhal-Teke. Data were analyzed using univariable and multivariable logistic regression. Proportion of colts was 63.0% (427/678), 46.1% (1,545/3,355), and 53.9% (247/458) in Arabian, Thoroughbred, and Akhal-Teke stallions, respectively. In Arabian stallions, SSR was skewed toward males (P < .0001; odds ratio, 1.701), whereas in Thoroughbred stallions, it was skewed toward females (P = .001; odds ratio, 0.853). Secondary sex ratio was not skewed in Akhal-Teke stallions (P > .05). Secondary sex ratio in Thoroughbred stallions was lower than that in Arabian (P < .0001; adjusted odds ratio, 1.983) and Akhal-Teke (P = .010; adjusted odds ratio, 1.527) stallions, but SSR did not differ between Arabian and Akhal-Teke stallions (P > .05). There was the effect of individual stallion on SSR in Arabian and Thoroughbred breeds (P < .0001) but not in Akhal-Teke breed (P > .05). In conclusion, the present study showed the effect of breed of stallion and stallion itself on sex ratio of foals.  相似文献   
43.
Luteal dysfunction has been observed in mares with defective uterine clearance. Association of low ovarian reserve with luteal dysfunction and abnormal endometrial thickness has been reported in bovine. Anti-Müllerian hormone (AMH) has been indicated as a marker for ovarian reserve in bovine and originates primarily from the ovary in equine. The present study evaluated serum AMH concentration in mares with delayed uterine clearance versus that in mares without delayed uterine clearance. Of 49 mares assigned to the study, 12 and 37 mares were diagnosed with and without delayed uterine clearance, respectively. Delayed uterine clearance was determined based on history and the observation of intrauterine fluid in ultrasonographic examination 24 hours after natural breeding. Serum AMH concentration was measured during estrus. Concentration of AMH was lower in mares with delayed uterine clearance (0.4 ± 0.1 ng/mL) than in those without delayed uterine clearance (1.1 ± 0.1 ng/mL). In conclusion, the present study indicated possible associations between ovary-lined mechanisms and uterine clearance failure in mares.  相似文献   
44.
The effects of corn particle size and dietary fibre on the performance, coefficient of apparent ileal digestibility (CAID) and intestinal characteristics in broiler starters fed pelleted diets were studied. The experiment included 10 treatments arranged as a 2 × 5 factorial with two corn particle sizes (GMD of 1071 [CGC] vs. 534 [FGC]) and five diets that consisted in a low-fibre diet and four extra diets resulting from the inclusion of insoluble fibre sources (10 g/kg of lignocellulose (LC), and 30 g/kg of oat hulls; OH, rice hulls; RH, and sunflower hulls; SFH). In coarse grinding, all-fibre sources improved body weight gain and feed intake compared to the control diet (p < 0.01). Feed conversion ratio (FCR) improved with fibre supplementation (p < 0.01) and fine grinding of corn (FGC) (p < 0.01). Coarse grinding of corn (CGC) and inclusion of RH, SFH and OH reduced gizzard pH (p < 0.01). Fibre inclusion increased ileal fat and Ca digestibility (p < 0.01), gizzard weight (p < 0.01), digesta transit time (p < 0.01) and length of duodenum and small intestine (p < 0.01). The CAID of phosphorus increased in CGC fed birds and inclusion of RH, SFH and OH (p < 0.05). The weight of gizzard, proventriculus and pancreas (p < 0.01) was greater in CGC fed birds. Feeding SFH, RH and OH (p < 0.01), and CGC (p < 0.01) increased the villus height (VH) of the duodenum. The OH, RH and SFH supplementation increased the caecal population of Lactobacillus spp. and total anaerobic bacteria (p < 0.01) only in FGC fed birds. Overall, birds fed pelleted diets containing RH, OH and SFH (3%) exhibited improved performance, and increased nutrient digestibility, which may be caused by developed gizzards and intestine. Furthermore, coarse grinding of corn is beneficial to gizzard development.  相似文献   
45.
A constructed wetland composed of a pond- and a marsh-type wetland was employed to remove nitrogen (N) and phosphorus (P) from effluent of a secondary wastewater treatment plant in Korea. Nutrient concentrations in inflow water and outflow water were monitored around 50 times over a 1-year period. To simulate N and P dynamics in a pond- and a marsh-type wetland, mesocosm experiments were conducted. In the field monitoring, ammonium (NH 4 + ) decreased from 4.6 to 1.7 mg L?1, nitrate (NO 3 ? ) decreased from 6.8 to 5.3 mg L?1, total N (TN) decreased from 14.6 to 10.1 mg L?1, and total P (TP) decreased from 1.6 to 1.1 mg L?1. Average removal efficiencies (loading basis) for NO 3 ? , NH 4 + , TN, and TP were over 70%. Of the environmental variables we considered, water temperature exhibited significant positive correlations with removal rates for the nutrients except for NH 4 + . Results from mesocosm experiments indicated that NH 4 + was removed similarly in both pond- and marsh-type mesocosms within 1 day, but that NO 3 ? was removed more efficiently in marsh-type mesocosms, which required a longer retention time (2?C4 days). Phosphorus was significantly removed similarly in both pond- and marsh-type mesocosms within 1 day. Based on the results, we infer that wetland system composed of a pond- and a marsh-type wetland consecutively can enhance nutrient removal efficiency compared with mono-type wetland. The reason is that removal of NH 4 + and P can be maximized in the pond while NO 3 ? requiring longer retention time can be removed through both pond and marsh. Overall results of this study suggest that a constructed wetland composed of a pond- and a marsh-type wetland is highly effective for the removal of N and P from effluents of a secondary wastewater treatment plant.  相似文献   
46.
The frequency and severity of drought is predicted to rise in many parts of the world. Considering that drought is the main constraint on rain-fed wheat crop production, both agronomic and genetic measures have been taken to minimize yield losses under drought. Beyond its role as a micronutrient, chloride also acts as an osmoticum, implicated in the regulation of stomatal aperture. This study explores the potential for chloride fertilization of Australian bread wheat (Triticum aestivum L.) to minimize grain yield losses caused by drought stress. For this, two drought-tolerant commercial genotypes (Mace and Gladius) and a well-studied drought-tolerant genotype used in wheat breeding (RAC875) were treated with ammonium chloride, potassium chloride, or ammonium bicarbonate, the latter two treatments served as controls for chloride and ammonium, respectively. Plants were grown under either a watered or water-restricted (drought) regime. The genotype RAC875 was found to accumulate leaf chloride at a significantly higher level than the other genotypes under optimal growth conditions. Under drought conditions, top-dressing RAC875 plants with ammonium chloride resulted in up to a 2.5-fold increase in grain number and this effect was not seen when plants were top-dressed with either of the control fertilizers. The ammonium chloride treatment also minimized losses of grain yield in RAC875 plants grown under drought. Treatment effects were accompanied by an increase in stomatal conductance. These results collectively suggest that the compound fertilizer ammonium chloride can improve drought tolerance of wheat.  相似文献   
47.
Mirtazapine (MRZ) is a human antidepressant drug that is metabolized, predominantly by the cytochrome P450 enzyme system, to 8-OH mirtazapine (8-OH MRZ) and dimetilmirtazapine (DMR) metabolites. In veterinary medicine, this drug is currently administered to cats and dogs with anorexia, although it could also have applications as an antidepressant, antiemetic, and analgesic agent in these species. The aim of this study was to assess the pharmacokinetics of MRZ and its metabolites DMR and 8-OH MRZ in horses. Six healthy female horses were administered MRZ (2 mg/kg) in fasting and fed states according to a balanced crossover study design. Plasma MRZ and metabolite concentrations were evaluated by high-performance liquid chromatography fluorescence detection method. Pharmacokinetic profiles of MRZ and DMR were similar (detected from 0.5 up to 34 and 48 hours, respectively), with an MRZ AUC0-N/DMR AUC0-N ratio range varying between 1.1 and 1.7. Surprisingly, 8-OH MRZ was undetected. Most of the pharmacokinetic parameters were not altered by food, with the exception of the time required to reach maximum concentration; this showed a statistical increase in subjects in the fasting state as compared with the fed state. However, because MRZ is an active substance intended for long-term administration, the slight increase of the time required to reach maximum concentration is not considered to be of any clinical consequence. In conclusion, the pharmacokinetic parameters demonstrated in this study suggest that MRZ is suitable for oral administration in the horse. However, further investigations are required to evaluate both its safety and effectiveness in this animal species.  相似文献   
48.
Zinc (Zn) and boron (B) disorders are common nutritional stresses in arid and semi-arid regions. In the current study, effectiveness of soil Zn amendment (0, 5.0, 10.0, and 20.0 mg kg–1 soil) using Zn-glycine chelate (Zn-Gly), a novel Zn-fertilizer, which is especially synthesized for application in calcareous soils in arid and semi-arid areas, was evaluated under different soil B levels (0, 2.5, 5.0, 10.0, and 20.0 mg kg–1 soil) for a 100-day period. Pistachio, the most valuable crop grown under arid conditions, was used as the model plant. Measurement of electrolyte leakage, H2O2, and malondialdehyde indicated the incidence of oxidative stress in the leaves of pistachio under low and high soil B concentrations. In addition, B stress caused a significant increase in lipoxygenase activity in the leaves. Plants treated with 5.0 mg B kg–1 soil showed the lowest oxidative stress injuries and lipid peroxidation. Application of 5.0 mg Zn kg–1 soil significantly alleviated the B stress damages, however, the ameliorative effect of Zn was vanished by application of higher Zn concentrations. Evaluation of the antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], or ascorbate peroxidase [APX]) and non-enzyme antioxidants (ascorbate and phenolic compounds) revealed that the protective effects of Zn-Gly against B stress are due to enhancement of cell antioxidant defense. In conclusion, application of Zn-Gly for reducing oxidative stress pressure in pistachio plants grown under B disorder was suggested.  相似文献   
49.
ABSTRACT

Sawing is the most common machining process and is present in both primary and secondary wood transformation sectors. The objective of this paper is to review how it is affected by different factors. The current challenges associated with various machining factors, process monitoring, and sensor selection were identified and explained. Consequently, four research challenges and technological gaps were outlined. (1) Contradictory results have been reported due to different cutting processes, wood species, measurement methods, and cutting speed range studied in literature, so special consideration needs to be taken when comparing results with those available in the literature. (2) Laboratory test conditions cannot yet fully represent the extreme cutting conditions in sawmills. More emphasis should be placed on those harsh industrial cutting conditions. (3) Research on wood cutting lacks multi-objective optimization approach, which suggests that sawdust generation should be simultaneously analysed with surface quality and power consumption. (4) Compared with metal cutting, little research has been conducted on wood sawing monitoring using an artificial intelligence approach, which should be prioritized in designing adaptive control systems. Combining intelligent monitoring and multi-objective optimization approaches should pave the way for controlling the sawing process so higher surface quality and cost efficient machining is achieved.  相似文献   
50.
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