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61.
62.
Yufang Guo Sukumar Saha John Z. Yu Johnie N. Jenkins Russell J. Kohel Brian E. Scheffler David M. Stelly 《Euphytica》2008,161(3):361-370
Bacterial artificial chromosome (BAC) libraries with large DNA fragment inserts have rapidly become the preferred choice for
physical mapping. BAC-derived microsatellite or simple sequence repeats (SSRs) markers facilitate the integration of physical
maps with genetic maps. The objective of this research was to identify chromosome locations of the BAC-derived SSR markers
in tetraploid cotton. A total of 192 SSR primer pairs were derived from BAC clones of an Upland cotton genetic standard line
TM-1 (Gossypium hirsutum L.). Metaphor agarose gel electrophoresis results revealed 76 and 59 polymorphic markers between TM-1 and 3–79 (G. barbadense) or G. tomentosum, respectively. Using deletion analysis method, we assigned 39 markers out of the 192 primer pairs to 17 different chromosomes
or chromosome arms. Among them, 19 and 17 markers were localized to A-subgenomes (chromosome 1–13) and D-subgenomes (chromosome
14–26), respectively. The subgenome status for the remaining three markers remained unclear due to their two potential chromosome
locations achieved by tertiary monosomic stocks deletion analysis. Chromosomal assignment of these BAC-derived SSR markers
will help in integrating physical and cotton genetic linkage maps and thus facilitate positional candidate gene cloning, comparative
genome analysis, and the coordination of chromosome-based genome sequencing project in cotton.
Disclaimer: Mention of trademark, proprietary product, or vendor does not constitute a guarantee or warranty of the product
by USDA, ARS and does not imply its approval to the exclusion of other products or vendors that may also be suitable.
The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. 相似文献
63.
64.
Uttam K. Saha Leticia Sonon Bipul K. Biswas 《Communications in Soil Science and Plant Analysis》2018,49(1):63-75
Soil mineral (or inorganic) nitrogen (SMN), which primarily exists as exchangeable and soluble ammonium (NH4+) and the nitrate (NO3?) ions, represents readily available nitrogen for plant growth. Over the years a 2M potassium chloride (KCl) solution has become the extraction solution of choice for extracting SMN. In the research and service laboratories, either distillation-titration method (DTM) or colorimetric method (CM) is virtually the standard to measure NH4+- and NO3?-N in the 2M KCl soil extracts. However, being a time-consuming and labor intensive method, DTM generally has a very low throughput. Likewise, CM is affected by interferences from pH variation, color, turbidity, presence of organic species, and some other constituents in the extracts. In contrast, diffusion conductivity method (DCM) is a less expensive and high throughput one, which is also relatively free from common interferences. In this study, we, therefore, compared the extraction efficiency of various KCl concentrations and performance of diffusion conductivity method (DCM) with DTM in measuring NH4+-N and NO3?-N in KCl extracts of 32 agricultural soils of Georgia. A 0.2M KCl solution extracted statistically similar amounts of NH4+-N and NO3?-N as did 2M KCl, suggesting that a 10-fold dilute KCl solution than the standard 2M KCl might be good enough to extract and estimate the most of SMN. For the analyses of NH4+- and NO3?-N in the KCl extracts, the DCM produced results statistically similar to those produced by DTM. The deviation between the results given by DCM and DTM was no more than ±10%. Thus, DCM appears to be an attractive alternative to the labor intensive and time-consuming DTM for measuring NH4+- and NO3?-N in the KCl extract of soils in the research and service laboratories. 相似文献
65.
Preparation of selective ion adsorbent by photo curing with acrylic and phosphoric acid on jute yarn
Md. Al-Mamun Mubarak A. Khan Ruhul A. Khan Haydar U. Zaman M. Saha S. M. F. Huque 《Fibers and Polymers》2010,11(6):832-837
Jute yarns were cured with acrylic acid (AA) and phosphoric acid (PA) using UV radiation in order to prepare selective ion
adsorbent. A series of formulations were prepared in methanol containing varying percentages of (10–70 %) of AA and 2 % photo-initiator
(PI) (Darocur-4043). jute yarns were soaked in this formulation for various soaking times (10–30 min) and cured under UV radiation
of different intensities (20–50 UV passes). Concentration of AA, soaking time and intensity of UV radiation were optimized
based on polymer loading (PL). The maximum PL (21 %) was observed for 50 % AA solution for 20 min soaking time at 40 UV passes.
Various formulations were prepared using 5–15 % (w/w) of phosphoric acid, 50 % AA and 2 % PI in methanol. Then jute yarns
were soaked in this solution for 20 min and irradiated at 40th UV pass. The concentration of PA was again optimized for maximum
PL. It was found that the formulation containing 10 % PA, 50 % AA, 38 % methanol and 2 % PI showed 70.95 % of PL. To investigate
the adsorbent behavior, a 10 ppm CuSO4 solution was prepared and then grafted yarns were soaked in the solutions for 30–300 min at different conditions. After withdrawing
the yarns, the remaining copper in the solution were measured by atomic absorption spectrophotometer (AAS). It was revealed
that copper was successfully removed by using the grafted jute yarns. 相似文献
66.
Dipanwita Haldar K. R. Manjunath Sushma Panigrahy Varunika Jain R. S. Gopalan Mukesh Khullar Manab Chakraborty J. S. Parihar 《Paddy and Water Environment》2015,13(4):343-352
Bringing green revolution in eastern India (BGREI) is an initiative of Department of Agriculture and Co-operation (DAC) Ministry of Agriculture (MoA), Govt. of India with the aim of increasing crop productivity through improved inputs and package of practices in seven states of eastern India comprising the low productivity zones. The current study aimed at assessment of the BGREI plots with respect to crop vigour variability using space-based observations. Synthetic aperture radar (SAR) data were used to assess the rice crop growth pattern and vigour through change in backscatter response. A SAR-based methodology was developed to evaluate the effect of BGREI initiative in the state of Odisha. The peak biomass, an indicator of crop vigour was 15–30 % higher in BGREI plots compared to the controlled plots. The improvement was higher in traditionally low productivity rainfed zones. Uniformity in growth in terms of growth rate, transplantation time and duration was observed in BGREI plots. The positive effect of BGREI in Odisha indicates that BGREI may be a breakthrough in improving rice productivity in low productivity zones of eastern India. 相似文献
67.
Phytoremediation, which mainly employs hyperaccumulators to remove heavy metals from contaminated soils, is receiving more attention world-wide. The identification of hyperaccumulators is still a key step for phytoremediation. This research is devoted to identify some plants with hyperaccumulative characteristics from weed species. In a pot culture experiment, the hyperaccumulative characteristics of 13 weed species in 11 families to Cd, Pb, Cu and Zn were examined. The result showed that Taraxacum mongolicum and Rorippa globosa indicated some Cd hyperaccumulative properties. In a sample-analysis experiment conducted in a Pb?Zn mining area, T. mongolicum and R. globosa also displayed the same hyperaccumulative characteristics. However, in a concentration gradient experiment, Cd content in shoot of T. mongolicum was not higher than 100 mg/kg (DW, dry weight), the minimum Cd concentration for a Cd-hyperaccumulator in any treatment. The concentration of Cd in the stems and leaves of R. globosa were greater than 100 mg/kg, under the conditions of the soils spiked with 25 and 50 mg/kg Cd. The Cd accumulation factors and translocation factors in the shoots of R. globosa were higher than 1 too, and the plant biomasses did not decrease significantly (p?<?0.05) compared with the control. Thus, we conclude that only R. globosa showed the whole Cd-hyperaccumulator properties, which is a Cd-hyperaccumulator. 相似文献
68.
Supradip Saha Ved Prakash Samaresh Kundu Narendra Kumar Banshi Lal Mina 《European Journal of Soil Biology》2008,44(3):309-315
Long-term experimental sites are expected to provide important information regarding soil properties as affected by management practices. This study was designed to examine the effects of continuous fertilization, and manuring on the activities of enzymes involved in mineralization of C, N, and P on a long term (33 years) field trial under sub-temperate conditions in India. Treatments at the site included application of recommended doses of nitrogen and phosphorus (NP), nitrogen and potassium (NK), nitrogen, phosphorus and potassium (NPK), farmyard manure (FYM) with N (N + FYM), FYM with NPK (NPK + FYM) and un-amended control (C). The study was done under rainfed soybean–wheat rotation. Manure application increased soil carbohydrate, dehydrogenase, acid and alkaline phosphatases, cellulase, and protease activity significantly. Urease activity was not influenced by the manure treatment and the activity was highest in controls. Both acid and alkaline phosphatase activities were negatively influenced by chemical fertilizer treatment. Almost all the enzymes studied were significantly correlated with soil C content. The results suggest that application of FYM directly or indirectly influences the enzyme activity and it in turn regulates nutrient transformation. 相似文献
69.
Abhijit Majumdar Anindya Ghosh Shib Sankar Saha Ayan Roy Subir Barman Dhrubajyoti Panigrahi Anjan Biswas 《Fibers and Polymers》2008,9(2):240-245
Aesthetic properties of fabrics have been considered as the most important fabric attribute for years. However, recently there
has been a paradigm shift in the domain of textile material applications and consequently more emphasis is now being given
on the mechanical and functional properties of fabrics rather than its aesthetic appeal. Moreover, in certain woven fabrics
used for technical applications, strength is a decisive quality parameter. In this work, tensile strength of plain woven fabrics
has been predicted by using two empirical modelling methods namely artificial neural network (ANN) and linear regression.
Warp yarn strength, warp yarn elongation, ends per inch (EPI), picks per inch (PPI) and weft count (Ne) were used as input
parameters. Both the models were able to predict the fabric strength with reasonably good precision although ANN model demonstrated
higher prediction accuracy and generalization ability than the regression model. The warp yarn strength and EPI were found
to be the two most significant factors influencing fabric strength in warp direction. 相似文献
70.
Bhanushree Narayanswami Bhoopal Singh Tomar Jameel Akhtar Tusar Kanti Behera Ranjith Kumar Ellur Rama Mithra V. Sevanthi Jaiswal Sarika Partha Saha 《Plant Breeding》2023,142(5):700-710
The present investigation was carried out to decipher inheritance of resistance and to identify linked SSR markers for Phomopsis blight resistance in eggplant. An F2 population comprising 161 plants was developed from the cross of Pusa Kranti and BR-40-7. Genetic analysis was carried out using Chi square test. Artificial inoculation of fruits was carried out using pin prick method, and scoring was done as per the standard scoring scale. The F2 plants segregated into 92 susceptible (77—highly susceptible, 15—susceptible): 69 resistant (17—highly resistant, 27—resistant, 25—moderately resistant) suggesting complimentary epistasis with ratio of 9:7. To identify the putatively linked markers to resistance gene, parental polymorphic markers were subjected to bulk segregant analysis (BSA), and two markers (emk03O04 and emf11A03) could differentiate resistant and susceptible bulk and co-segregated with resistance gene. The genetic distance between the identified markers was found to be 18.12 cM using QTL IciMapping V3.2 software depicting two new QTLs on chromosome number 6. The identified QTLs have great significant importance in marker assisted breeding programme. 相似文献