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131.
Carbon nanotube (CNT)/magnetite (Fe3O4) nanocomposites were successfully fabricated by nanocoating. When the CNT/Fe3O4 nanocomposites were added to a carbonyl (CI) based magnetorheological fluid (MRF), the magnetic rheological properties of
the MRF were enhanced. Such enhancement in magnetic rheological properties of the CI-CNT/Fe3O4 MRF is considered to be attributable to both the superparamagnetic property of the magnetic layer covering the CNT surface
and the high length to diameter ratio of the CNT/Fe3O4 nanocomposite. Impact properties for CI-CNT/Fe3O4 MRF treated Kevlar fabrics were also tested, and improved impact properties were observed with external magnetic fields compared
to CI-MRF treated Kevlar fabrics. 相似文献
132.
Silsesquiazane (SSQZ), one of the branched forms of polysilazane, was blended with polystyrene (PS), poly(methyl methacrylate) (PMMA), poly(iso-butyl methacrylate) (PBMA), and poly(vinyl acetate) (PVAc) to produce organic-inorganic hybrid materials. The polymers were selected to provide specific interaction, such as ??-?? interaction or hydrogen bonding, with SSQZ. AFM studies revealed that carbonyl containing polymers, PMMA, PBMA, and PVAc were miscible with SSQZ while PS was immiscible. DSC analysis of the hybrids also supported the miscibility behaviours of the system. The glass transition behaviour of SSQZ/PS showed individual transition temperature corresponding to the each component while SSQZ/carbonyl-containing polymers displayed one transition temperature that matched with the theoretically calculated values following the Kwei equation. Among the miscible hybrid system, the interaction with SSQZ increased in the order of PMMA> PBMA> PVAc, as determined by the q value in the Kwei equation. This result was confirmed by determining the degree of hydrogen bonding in FT-IR spectra. Thermal stability of organic polymers was improved by incorporating SSQZ regardless of the miscibility. 相似文献
133.
A multiplex polymerase chain reaction (m-PCR) technique was developed as a rapid and accurate diagnostic tool for identifying five major Gram-negative bacilli -Vibrio vulnificus, V. parahaemolyticus, Aeromonas hydrophila, Chryseobacterium meningosepticum and Edwardsiella tarda- that cause major diseases in cultured aquatic animals in Taiwan. The expected amplicons for V. vulnificus, V. parahaemolyticus, A. hydrophila, C. meningosepticum and E. tarda were 410, 368, 685, 180 and 230bp, respectively. The assay was shown to be specific for the target pathogens. The sensitivities of detection were estimated to be 20.5fg~200pg of genomic DNA or 10(2) ~10(4) colony-forming units (cfu) of bacterial isolates when adopted as PCR templates. The m-PCR was capable of simultaneously amplifying target fragments from bacterial genome DNA mixed with the DNA extracted from viscera and tissues taken from fish without affecting the performance of the method. 相似文献
134.
Ha Duy Truong Chong Ho Wang Tran Trung Kien 《Communications in Soil Science and Plant Analysis》2017,48(14):1701-1709
This research was conducted to investigate the effects of different medium compositions on physicochemical properties and the growth of two tomato varieties. Five treatments were applied, combining medium composition with rice husk ash (RHS) and coconut fiber (CF) with the following proportions: 1/3 Peat moss + 1/3 rice husk ash + 1/3 coconut fiber (T1); 1/3 Vermicompost + 1/3 rice husk ash + 1/3 coconut fiber (T2); 1/3 Cattle manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T3); 1/3 Chicken manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T4); 1/3 Hog manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T5). The results demonstrated that between pH, electrical conductivity (EC) value, and nutrient content in the media, there was a significant difference that led to different concentrations of total macro- and micronutrients in the shoots of both varieties. In addition, the root weight, shoot weight, and root volume were affected by medium composition for two varieties in seedling stage. A mixture of cattle manures composted with RHS and CF under the rate (1:1:1 by volume), respectively, gave the highest value of germination rate, plant height, leaf number, and plant biomass. Medium composition significantly influenced the germination rate and elongation of seedlings, specifically for each tomato variety. Therefore, cattle manure compost as a medium supplement improves seedling quality and growth of the two tomato varieties. 相似文献
135.
Solid-state polymerization of poly(trimethylene terephthalate)(PTT) was carried out to obtain high molecular weight polymers.
Two kinds of commercial PTT chips were polymerized in the solid state by the heat treatment at 190∼220°C for various times
and they were characterized by end group content, molecular weight, thermal analysis, and X-ray diffraction. In the solid-state
polymerization of PTT, the overall reaction rate was governed by the solid-state polymerization temperature and time, and
pellet size. The content of carboxyl end groups decreased during the solid-state polymerization with increasing solid-state
polymerization temperature and time. The melting temperature and crystallinity of the PTT were higher for the ones treated
at higher temperature and longer time. The activation energy for the solid-state polymerization of PTT was in the range of
24∼25 kcal/mol for both chips. Through the solid-state polymerization of commercial PTT chips, high molecular weight polymers
up to an intrinsic viscosity of 1.63 dl/g was obtained, which corresponded to about a 117,000 weight-average molecular weight. 相似文献
136.
Hyeok Ran Kwon Gyung Ja Choi Yong Ho Choi Kyoung Soo Jang Nack‐Do Sung Mun Seong Kang Yilseong Moon Seung Kyu Lee Jin‐Cheol Kim 《Pest management science》2010,66(6):634-639
BACKGROUND: Pine wilt disease (PWD) is very complex and has been reported to be caused by pine wood nematode, Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle, and its accompanying bacteria. However, there is no report on the control of PWD by antibacterial agent. The present study was performed to investigate disease control efficacy of antibacterial agents against PWD. RESULTS: Among six antibacterial antibiotics tested, oxolinic acid (OA) showed the strongest antibacterial activity against five bacteria isolated from three strains of pine wood nematode. In in vivo assay, it effectively suppressed the development of PWD in three‐year‐old seedlings of Pinus densiflora Sieb. & Zucc.; it showed 71% control when injected at 3 mg per seedling. A mixture of OA and the nematicidal agent abamectin (Ab) showed higher disease control efficacy against PWD than either OA or Ab alone. In addition, OA alone and a mixture of OA and Ab also controlled PWD in approximately 20‐year‐old pine trees under field conditions. CONCLUSION: This is the first report on the suppression of PWD by OA. The result strongly indicates that PWD could be controlled by antibacterial antibiotic alone and a combination of antibacterial and nematicidal agents. Copyright © 2010 Society of Chemical Industry 相似文献
137.
138.
Woong Yoon Jung Min Ryu Min Young Lee Yong Ju Moon Sang Hun Lee Jae Hong Park Seung Pil Yun Min Woo Jang Sung Su Park Ho Jae Han 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(3):185-189
Micropigs are the most likely source animals for xenotransplantation. However, an appropriate method for evaluating the lung of micropigs had not been established. Therefore, this study was performed to evaluate the feasibility of 64-channel multi-detector row computed tomography (MDCT) to measure the diameter of the pulmonary arteries and the lung volume in micropigs. The mean diameters of the trachea, and left and right bronchi were 1.6 ± 0.17, 1.18 ± 0.14, and 1.1 ± 0.11 cm, respectively. The mean diameters of the main, right, and left pulmonary arteries were 1.38 ± 0.09, 1.07 ± 0.26, and 0.98 ± 0.13 cm and the diameters of right, left, and common inferior pulmonary veins were 0.97 ± 0.20, 0.76 ± 0.20, and 1.99 ± 0.26 cm, respectively. The mean lung volume was 820.3 ± 77.11 mL. The data presented in this study suggest that the MDCT may be a noninvasive, rapid, and accurate investigational method for pulmonary anatomy in living lung donors. 相似文献
139.
Tran Ho Quang Nguyen Duc Kien Sara von Arnold Gunnar Jansson Ha Huy Thinh David Clapham 《New Forests》2010,39(3):301-312
Lignin and cellulose contents and wood basic density were related to diameter at breast height (DBH) in six fast-growing and
five slow-growing families from a combined progeny test and seedling seed orchard of Eucalyptus urophylla grown for 10 years in northern Vietnam. The mean cellulose content of the fast-growing families was significantly higher
than that of the slow growing-families (40.0 and 37.1%, respectively), and for individual trees cellulose content was significantly
correlated phenotypically with DBH. Wood basic density was significantly lower in the fast-growing group than in the slow-growing
group (0.506 and 0.535 g cm−3, respectively), and was significantly negatively correlated phenotypically with DBH. The lignin contents were not significantly
different between groups. Cellulose content and wood basic density were not correlated. The main conclusion is that there
is no obstacle to combining high growth rate with high cellulose content, for plantation of forests intended mainly for pulpwood. 相似文献
140.