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1.
Composites based on pure Basalt and Basalt/Jute fabrics were fabricated. The mechanical properties of the composites such as flexural modulus, tensile modulus and impact strength were measured depending upon weave, fiber contents and resin. Dynamic mechanical analysis of all composites were done. From the results it is found that pure basalt fiber combination maintains higher values in all mechanical tests. Thermo-gravimetric (TG/DTG) composites showed that thermal degradation temperatures of composites shifted to higher temperature regions compared to pure jute fabrics. Addition of basalt fiber improved the thermal stability of the composite considerably. Scanning electron microscopic images of tensile fractured composite samples illustrated that better fiber-matrix interfacial interaction occurred in hybrid composites. The thermal conductivity of composites are also investigated and thermal model is used to check their correlation.  相似文献   
2.
We report the field evaluation of second generation of transgenic cotton expressing Bacillus thuringiensis (Bt) genes cry1Ac and cry2A under CaMV 35S promoter. Sixty-five transgenic lines were grown under RCBD design. Transgenic plants exhibited inherent ability to resist target insect (p < 0.05 and 0.01). Morphological studies showed significant reduction in plant height making them favorable for breeding. Yield was significantly increased for the transgenic lines. Fiber analysis showed improved gin turn out 40% for transgenic lines in comparison to 32% for non-transformed lines. Fibre quality of transgenic lines was not affected when compared with non transgenic lines. Inheritance pattern for transgenic lines suggests the need of further studies to understand the complex molecular mechanisms for resistance management and biosafety studies to develop new Bt cotton varieties.  相似文献   
3.
We focused on key aspects of forest governance for biodiver- sity conservation in implementing new climate change policies. The national forest institutions must be adaptive to identify the existing pitfalls of prior conservation policies to take advantage of new climate change policies. Strengthening roles and technical capacity of national institutions for systematic biodiversity monitoring and carbon stock assessment is required in developing and least developed countries. Community participation needs careful analysis to ensure equitable ac- cess of particular social groups to local decision-making processes and to sustain optional livelihoods. The livelihood options around forest reserves or protected areas must be taken into account to enhance forest-based adaptation.  相似文献   
4.
Various feeding studies have been conducted with the different species of animals to evaluate the possible transfer of transgenic DNA (tDNA) from genetically modified (GM) feed into the animal tissues. However, the conclusions drawn from most of such studies are sometimes controversial. Thus, in the present study, an attempt has been made to evaluate the fate of tDNA in rabbits raised on GM cotton-based diet through PCR analysis of the DNA extracted specifically from blood, liver, kidney, heart and intestine (jejunum). A total of 48 rabbits were fed a mixed diet consisting variable proportions of transgenic cottonseeds meal (i.e. 0% w/w, 20% w/w, 30% w/w and 40% w/w) for 180 days. The presence of transgenic DNA fragments (Cry1Ac, Cry2A and CP4 EPSPS) or plant endogenous gene (Sad1) was traced in those specific tissues and organs. The presence of β-actin (ACTB) was also monitored as an internal control. Neither the transgenic fragments (459 bp of Cry1Ac gene, 167 bp of Cry2A gene and111 bp of CP4 EPSPS gene) nor cotton endogenous reference gene (155 bp of Sad1) could be detected in any of the DNA samples extracted from the rabbit's tissues in both control and transgenic groups. However, 155 bp fragment of the rabbit's reference gene (ACTB) was recovered in all the DNA samples extracted from rabbit tissues. The results obtained from this study revealed that both plant endogenous and transgenic DNA fragments have same fate in rabbit's tissues and were efficiently degraded in the gastrointestinal tract (GIT).  相似文献   
5.
Facile embedding of TiO2 nanoparticles onto cotton fabric has been successfully attained by ultraviolet light irradiations. The adhesion of nanoparticles with fibre surface, tensile behaviour and physicochemical changes before and after ultraviolet treatment were investigated by scanning electron microscopy, energy dispersive X-ray and inductive couple plasma-atomic emission spectroscopy. Experimental variables i.e. dosage of TiO2 nanoparticles, temperature of the system and time of ultraviolet irradiations were optimised by central composite design and response surface methodology. Moreover, two different mathematical models were developed for incorporated TiO2 onto cotton and tensile strength of cotton after ultraviolet treatment and used further to testify the obtained results. Self-clean fabric through a synergistic combination of cotton with highly photo active TiO2 nanoparticles was produced. Stability against ultraviolet irradiations and self-cleaning properties of the produced fabric were evaluated.  相似文献   
6.
The present study was conducted to evaluate inheritance pattern of insecticidal gene (Cry1Ab) in F1 and F2 generations derived from six combinations of crosses made between two transgenic lines (CEMB-3 and CEMB-11) and two non transgenic lines (MNH-93 and CIM-482). PCR, southern blot, western dot blot assay and lab biotoxicity assay were used to confirm the gene integration and expression of insecticidal gene in successive generations. The insecticidal gene was stably integrated in the genome of all F1 plants showing the dominant nature of introduced gene (cry1Ab). Furthermore, heterosis, heterobeltiosis, heritability and genetic advance studies of Bt gene were also conducted. Heterosis and heterobeltiosis were estimated for five characters i.e. cotton yield per plant, no. of bolls per plant, boll weight, ginning out turn % age and laboratory bioassay results. The heterosis and heterobeltiosis ranged from??15.19 to 107.07% and 18.58 to 98.79%, respectively for yield per plant; from ?20.34 to 81.36% and ?20.34 to 81.36%, respectively for number of bolls per plant; from -6.96 to 21.38% and ?9.30 to 9.99%, respectively for boll weight; from 13.02 to 26.44% and ?0.52 to 26.17%, respectively for ginning outturn; and from ?8.11 to 36.23% and ?5.56 to 23.68%, respectively for mortality % age of Heliothis larvae in laboratory bioassays. The Broad Sense Heritability and Genetic Advance for insect resistance in Bt versus non-Bt crosses were calculated. Both of these were high in four out of six hybrids. Our data recorded showed that these transgenic lines are an excellent source of germplasm to be used in conventional breeding programme.  相似文献   
7.
Maghemite glass fibre nanocomposite with excellent magnetic and adsorption properties was successfully developed from nontoxic and eco-friendly reagents by thermal decomposition approach. The developed nanocomposite was utilized in adsorption of methylene blue which follows Freundlich adsorption isotherm. The excellent value of adsorption capacity (51.31 mg g-1) as compared to other adsorbents recommends its potential role for adsorption phenomenon in multiple applications. The developed nanocomposite can be recycled and reused easily. Surface and other functional characteristics of developed nanocomposite were determined through scanning electron microscopy, X-ray diffraction, raman spectroscopy, energy dispersive X-ray spectroscopy and vibrating sample magnetometer. The obtained results revealed that maghemite glass nanocomposite is a potential tool that can be utilized in waste water treatments.  相似文献   
8.
Sahiwal cow is Bos indicus which is an important dairy breed of tropical and sub‐tropical region. Research on reproduction is rare in this breed. The objectives of the present study were to determine the effect of Ovsynch (OVS) versus prostaglandin F (PG) protocol on estrus response and its intensity, ovulation rate, timing of ovulation and pregnancy per artificial insemination (AI) in Sahiwal cows. Experimental cows (n = 80) were of mixed parity, lactating, suckled, ≥120 days postpartum with body condition score 3.08 ± 0.34 and 375‐475 kg of body weight which were randomly assigned to receive either OVS (n = 46) or PG (n =34) protocol. Cows were inseminated twice at 12 and 24 h after second gonadotropin releasing hormone in the OVS group, and 72 and 84 h after administration of prostaglandin F in PG group, respectively. The results revealed that estrus response did not differ (P > 0.05) and was 87% in OVS and 78% in PG cows. Ovulation rate did not differ (P > 0.05) and was 50% in both, OVS and PG cows. The pregnancy per AI did not differ (P > 0.05) and was 43% in OVS compared to 31% in PG cows. It is concluded that estrus response, ovulation rate and pregnancy per AI of OVS protocol is the same as PG in Sahiwal cows.  相似文献   
9.
10.
Genetically modified (GM) crops expressing insect resistance and herbicide tolerance provide a novel approach for improved crop production but their advent at the same time presents serious challenges in terms of food safety. Although prevailing scientific proof has suggested that transgenic crops are analogous to their conventional counterparts, their use in human and animal diet gave rise to emotional public discussion. A number of studies had been conducted to evaluate the potential unintended effects of transgenic crops expressing single transgene, but very few studies for those with multiple transgenes. As the crops with single and multiple transgenes could impart different effects on non‐target organisms, thus, risk evaluation of transgenic crops expressing more than one transgene is required to declare their biosafety. The present study was therefore designed to assess the effects of different levels of dietary transgenic cottonseed expressing recombinants proteins produced by Cry1Ac, Cry2A and Cp4epsps genes on haematological indices of growing rabbits. A total of 48 rabbits were assigned to four dietary treatments containing different levels of transgenic cottonseeds (i.e., 0% w/w, 20% w/w, 30% w/w and 40% w/w) with 0% w/w serving as control. Haematological parameters were measured at periodic intervals (0, 45, 90, 135 and 180) days. No significant (p > 0.05) dose‐dependent effects were observed in most of the haematological parameters evaluated. Though, significant differences (p < 0.05) were recorded in the level of MCHC, MCH and HCT in some of experimental male and female rabbits, yet, they were not biologically significant, as all the differences were within the normal reference values. Our study suggested that feeding transgenic cottonseed of up to 40% could not adversely affect rabbit's haematological profile. However, further study needs to be conducted with different cotton genotypes expressing both single and polygenic traits before recommending the utilization of transgenic cottonseed in routine livestock feeding.  相似文献   
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