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Polyvinylidene fluoride (PVdF) membranes in spite of having many critical properties necessary for lithium-ion batteries, do not have satisfying thermal and mechanical resistance. The goal of this study was to combine the good mechanical and thermal properties of PP nonwoven fabric with the excellent electrochemical properties of PVdF nanofibers to exploit a high-performance membrane for lithium-ion batteries. This work reports the preparation of PVdF nanofiber membranes using electrospinning on a polypropylene (PP) spunbonded nonwoven fabric and an aluminum foil followed by a hot-pressing treatment. The morphology and size of the membranes were studied by the scanning electron microscopy. The tensile strength of the membrane with the PP support was superior to the PVdF membrane. Thermal stability of the prepared membranes was determined using the TGA method and the dimensional stability was investigated by measuring the shrinkage ratio at 105 °C. The results have shown that the PVdF/PP membrane was thermally more stable than the PVdF and the commercial Celgard 2325 membranes. The batteries using PVdF/PP membrane exhibited higher electrochemical oxidation limit, better cycling performance and less discharge capacity fading during 100 cycles compared to PVdF and Celgard membranes. The results of this study showed that PVdF/PP membrane is a promising advanced membrane in lithium-ion batteries.  相似文献   
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The aim of this study was to determine the effects of dietary probiotics on reproductive performance, growth, haematological and biochemical parameters of female rainbow trout broodstock. A total of 60 broodstocks with an average initial weight of 2,267.4 ± 54.9 g were divided into four groups and three replicates in raceway ponds. Fish were fed with diets containing 0 (control), 1 × 109 (P1), 2 × 109 (P2) and 4 × 109 (P3) CFU probiotic per kg diet twice a day for 8 weeks before spawning season. Results revealed that higher levels of dietary probiotics (P3) enhanced protein efficiency ratio and decreased feed conversion ratio (p < .05). There were no significant differences in haematological and other growth parameters among different treatments. According to the results, probiotic‐fed treatments had the lowest levels of cholesterol (237.7 ± 4.3 mg/dl) and the highest levels of total protein (11.3 ± 0.3 g/dl) and albumin (6.9 ± 0.3 g/dl), so that differences were found between P3 and control groups in all cases (p < .05). Based on the observations from reproductive parameters, the highest egg diameter, working and relative fecundities, fertilization and hatching rates, eyed eggs survival and alevins survival rates up to the absorption of the yolk sac were observed in P3 treatment (p < .05). Moreover, eyeing, hatching and yolk sac absorbing stages in P3 treatment were earlier than those in other treatments (p < .05). The results of present study demonstrated that probiotic supplementation improved reproductive performance and some growth and biochemical parameters in female rainbow trout broodstock and the best performance was observed in fish fed 4 × 109 CFU probiotic per kg diet. Due to an increase in egg production and egg size in probiotic‐fed treatments, this feed additive can be used as a suitable ingredient to increase high‐quality egg production in rainbow trout breeders.  相似文献   
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A feeding trial was carried out to determine the effects of bioflocs on dietary protein requirement in juvenile whiteleg shrimp, Litopenaeus vannamei. Four bioflocs treatments (BFT) and one control group were managed: BFT fed diets 25% of crude protein (CP) (BFT‐25%), 30% CP (BFT‐30%), 35% CP (BFT‐35%) and 40% CP (BFT‐40%), and clear water control without bioflocs fed with 40% CP (CW‐40%). Triplicate groups of shrimp (initial body weight, 1.3 g) were fed one of the test diets at a ratio of 7% body weight daily for 8 weeks. At the end of the feeding trial, significantly (P < 0.05) higher weight gain and specific growth rate were obtained in shrimp fed BFT‐35% and BFT‐40% compared to BFT‐25% and BFT‐30%. Shrimp fed BFT‐35% exhibited the lowest feed conversion ratio. Significantly higher muscle nucleic acid indices were also recorded such as DNA content in BFT‐30%, RNA content in BFT‐35% and RNA/DNA ratio than that of shrimp fed control. Total protein level in the haemolymph of shrimp fed BFT‐40% was significantly higher than those of shrimp fed BFT‐25% and BFT‐30%. Therefore, the present results demonstrated that, when L. vannamei juveniles were reared in bioflocs‐based tanks, dietary protein level could be reduced from 40% to 35% without any adverse effect on shrimp growth performance, body composition and haemolymph characteristics. [Correction added on 20 May 2015, after first online publication: sentence modified to clarify the reduction in dietary protein level.].  相似文献   
4.
A feeding trial was conducted to determine the optimum level and effect of incremental dietary levels of docosahexaenoic acid (DHA, 22:6n‐3) on growth and non‐specific immune responses in juvenile rock bream, Oplegnathus fasciatus. A basal diet without DHA supplementation was used as a control, and six other diets were prepared by supplementing with 4, 8, 12, 16, 20 or 40 g kg?1 DHA. These diets included no eicosapentaenoic acid and/or arachidonic acid contents. The actual DHA concentrations of the diets were 1, 4.8, 8.9, 13.1, 17.6, 21.2 and 41.4 g kg?1 diet (DHA1.0, DHA4.8, DHA8.9, DHA13.1, DHA17.6, DHA21.2 and DHA41.4 respectively). At the end of feeding trial, final body weight, weight gain, specific growth rate and feed efficiency of fish fed the DHA13.1, DHA17.6, DHA21.2 and DHA41.4 diets were significantly higher than those fed the other diets (P < 0.05). The broken‐line analysis of weight gain indicates that the optimum dietary DHA level is 11.9 g kg?1. Fish fed DHA1.0 had the highest hepatosomatic index, an increase in plasma cholesterol, triglyceride, low‐density lipoprotein and aspartate aminotransferase levels, as well as a decrease in high‐density lipoprotein. Superoxide dismutase activity of fish fed DHA13.1 and DHA17.6 diets was significantly higher than that of fish fed DHA1.0, DHA4.8 and DHA8.9 diets. Fish fed the DHA17.6, DHA21.2 and DHA41.4 diets showed significantly higher lysozyme activity than those fish fed DHA1.0, DHA4.8 and DHA8.9 diets. Therefore, the optimum dietary DHA level could be greater than 11.9 g kg?1 but less than 13.1 g kg?1 in diet.  相似文献   
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An 8‐week feeding trial was conducted to evaluate the optimum dietary protein‐to‐energy (P/E) ratio in juvenile whiteleg shrimp, Litopenaeus vannamei. Six diets were formulated with two protein levels (30% and 35%) and three digestible energy levels (16, 17.5 and 19 kJ/g diet) at each protein level (30P16, 30P17.5, 30P19, 35P16, 35P17.5 and 35P19). Fifty shrimp averaging 0.97 ± 0.03g (Mean ± SD) were randomly distributed in biofloc tanks and fed one of the experimental diets. Weight gain (WG), specific growth rate (SGR) and feed efficiency (FE) of shrimp fed the 35P17.5 diet were significantly higher than those of shrimp fed 30P16, 30P17.5 and 30P19 diets (< .05). Results for non‐specific immune responses showed that diet 35P17.5 caused higher lysozyme activity in shrimp comparing to lower protein diets. Thiobarbituric acid reactive substances (TBARS) of plasma were lower for shrimp fed on diets consisting of higher protein and energy levels than shrimp fed on the 30P19 diet. Analyses of digestive enzyme activities showed higher trypsin activities for shrimp fed on 35P17.5 and 35P19 diets comparing to 30P16 and 30P17.5 diets. Also, hepatopancreatic lipase activity of shrimp fed 35P16, 35P17.5 and 35P19 diets were significantly higher than those of shrimp fed the other diets. In conclusion, based on the results for growth performance, biochemical parameters, immune responses, oxidative stress and enzyme activities, 35% protein and 17.5 kJ/g digestible energy (35P17.5) could be considered as the optimum protein‐to‐energy ratio in the diet of juvenile whiteleg shrimp reared in a biofloc system.  相似文献   
7.
In contrast to chickens, there is a paucity of information on the potency of H5 vaccines to protect turkeys against the highly pathogenic avian influenza (HPAI) H5N1 virus infections. In this study, 4 groups, 10 turkey poults each, were vaccinated at seven days old with one of H5N2 or H5N1 commercial vaccines or one of two prepared H5N1 vaccines from a local Egyptian variant HPAI H5N1 (EGYvar/H5N1) strain. At 35 days age, all vaccinated and 10 non vaccinated birds were challenged intranasal with 10(6) EID(50)/0.1 ml of EGYvar/H5N1. All vaccines used in this study were immunogenic in turkeys. There was no cross reaction between the commercial vaccines and the Egyptian variant H5N1 antigen as obtained by the hemagglutination inhibition test. Birds vaccinated with H5N2 vaccine were died, while other H5N1 vaccinated groups have had 20-40% mortality. The highest virus excretion was found in non-vaccinated infected and H5N2 vaccinated birds. Eleven peculiar amino acid substitutions in H5 protein of the variant strain were existed neither in the vaccine strains nor in the earliest H5N1 virus introduced into Egypt in 2006. In conclusion, single vaccination at seven days old is inadequate for protection of meat turkeys against variant HPAI H5N1 challenge and multi-dose vaccination at older age is recommended. For the foreseeable future, continuous evaluation of the current vaccines in H5N1 endemic countries in the face of virus evolution is a paramount challenge to mitigate the socio-economic impact of the virus.  相似文献   
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Different levels of dietary soybean meal (SBM) as a fish meal (FM) replacer, with and without amino acid supplementation, for whiteleg shrimp, Litopenaeus vannamei reared in the biofloc system was examined in eight weeks of feeding trial. Eight experimental diets consisted of a basal diet with 0% FM replacement by SBM provided in clear sea water without biofloc system (S0SW), four diets replacing FM at 0% (S0), 33% (S33), 67% (S67) and 100% (S100) by SBM, and three diets replacing FM at 33% (S33A), 67% (S67A) and 100% (S100A) by SBM supplemented with amino acids (methionine and lysine) in the seawater biofloc system. Results of water quality analyses showed significantly lower total suspended solids and nitrate for S0SW group than all other treatments. Diets S0 and S33A resulted in higher weight gain and specific growth rate among all groups, with no significant differences with S33 group. In addition, whole-body protein and amino acid compositions of shrimp fed S0SW were lower than most biofloc groups. Haemolymph parameters showed significant differences in total protein, cholesterol and triglyceride between groups S0 and S0SW. Also, superoxide dismutase activity showed a decreasing trend with increasing replacement level. In conclusion, based on these results, SBM could replace up to 33% of FM with or without amino acid supplementation in juvenile whiteleg shrimp diets reared in the biofloc system.

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