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81.
Scrap rubber reclamation is one of the most desirable approaches to solve the disposal problem of used tires. However, reclaimed tire rubber (RTR) has not gained enough attention due to its poor properties. In this work, the effects of poly(ethylene‐co‐vinyl acetate) (EVA) addition and electron beam (EB) irradiation on the properties of RTR were studied. The RTR/EVA blends containing 100–0 wt % of RTR were prepared in the internal mixer followed by EB irradiation with doses ranging from 50 to 200 kGy. The RTR/EVA blends were subjected to mechanical, gel content, thermal, and morphological analysis. It was found that the addition of EVA to RTR improved the mechanical properties of RTR. However, results revealed that RTR undergoes irradiation‐induced crosslinking in a relatively lesser extent as compared to EVA. This observation is associated with the stabilization and radical scavenging effects of additives, which are present in the RTR matrix. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41649.  相似文献   
82.
Textile can be a potential microorganism's propagation site because it contacts with human skin endows optimal conditions combination of nutrient sources, temperature, and moisture which provides conducive environment for microorganism growth. Thus, the development of antibacterial textile is crucial to inhibit the growth of microorganisms for protection the health and safety of wearer. This review article focuses on several metal‐based nanoparticles possess biocidal feature namely, Ag, ZnO, Cu based, TiO2, and other minor metals based such as iron based, CeO2, Au, SiO2, Ni, and Pt. The phenomenology of metal nanoparticles associated to the antibacterial effects and possible mechanisms of action against bacteria have been highlighted. This review also discussed the synthesis techniques and effects of incorporation additive materials of those metal‐based nanoparticles to inhibit the growth of microorganisms. J. VINYL ADDIT. TECHNOL., 2017. © 2017 Society of Plastics Engineers  相似文献   
83.
Linear low‐density polyethylene/soya powder blends were prepared by using an internal mixer at 150°C. The soya powder content ranged from 5 to 40 wt %. Epoxidized natural rubber with 50 mol % epoxidation (ENR 50) was added as a compatibilizer. The blends were irradiated by electron beam (EB) at a constant dose of 30 kGy. The changes in gel fraction, tensile properties, morphological and thermal properties of the samples were investigated. The gel content increased after EB irradiation. However, the increment of gel content was hindered by increasing soya powder content. The tensile strength and Young's modulus of the blends were increased by EB whereas the elongation at break decreased. The tensile fracture surface also support the reduction of elongation at break by EB irradiation. Further analysis on the irradiated blends using Fourier transform infrared spectra indicated an increase of oxygenated product after undergoing EB irradiation. The differential scanning calorimetry result indicated that the melting temperature of the blends decreased after EB irradiation whereas the crystallinity increased. EB irradiation also enhanced the thermal stability of the blends as indicated by thermogravimetric analysis. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
84.
Many of the plant leucine rich repeat receptor-like kinases (LRR-RLKs) have been found to regulate signaling during plant defense processes. In this study, we selected and sequenced an LRR-RLK gene, designated as Oryza rufipogon receptor-like protein kinase 1 (OrufRPK1), located within yield QTL yld1.1 from the wild rice Oryza rufipogon (accession IRGC105491). A 2055 bp coding region and two exons were identified. Southern blotting determined OrufRPK1 to be a single copy gene. Sequence comparison with cultivated rice orthologs (OsI219RPK1, OsI9311RPK1 and OsJNipponRPK1, respectively derived from O. sativa ssp. indica cv. MR219, O. sativa ssp. indica cv. 9311 and O. sativa ssp. japonica cv. Nipponbare) revealed the presence of 12 single nucleotide polymorphisms (SNPs) with five non-synonymous substitutions, and 23 insertion/deletion sites. The biological role of the OrufRPK1 as a defense related LRR-RLK is proposed on the basis of cDNA sequence characterization, domain subfamily classification, structural prediction of extra cellular domains, cluster analysis and comparative gene expression.  相似文献   
85.
OBJECTIVES: To update information on endogenous retroviral sequences and discuss their role in systemic autoimmune disease. DATA SOURCES: Articles retrieved after MEDLINE search and personal communications and cooperation with the Institute of Virology. DATA SYNTHESIS: There are 2 modes of pathogenetic mechanisms through which endogenous retroviral sequences could cause systemic autoimmune disease: expression of endogenous retroviral gene products sharing antigenic determinants with cellular proteins; and activation or destruction of cellular genes as a consequence of insertional mutagenesis. Both mechanisms have been demonstrated in vitro and in vivo in animal models. CONCLUSION: Investigations on endogenous retroviral sequences in humans may offer new insights into the pathogenesis of autoimmune disease.  相似文献   
86.
We report a caroticocavernous fistula (CCF) treated by an endovascular procedure in a young woman with Ehlers-Danlos syndrome type IV, with severe bilateral carotid and vertebral artery dysplasia. The CCF, which appeared after minor trauma, was successfully occluded by a detachable balloon introduced into the venous side by an arterial approach. Six previously published cases are reviewed, five successfully treated. The difficulties and risks of the endovascular procedure due to the vascular changes, are emphasised. The possibility of the venous approach is discussed.  相似文献   
87.
Expanded polystyrene (EPS) has been widely used as a disposable packaging material in many industries thanks to properties like low density, lightweight, high impact, and vibration damping. Although usage of EPS increases annually, recycling facilities often refused to process postconsumed EPS due to the poor economic viability associated with high logistics and transportation cost in collection, storage, and shipment of the material. The objective of this research is to enhance the value chain of postconsumed EPS by investigating its potential as feedstock in the development of sustainable wood plastic composites (WPC), thereby providing an attractive business opportunity that also increases interest in EPS recycling and indirectly continue the lifespan of disposed EPS. Varying compositions of recycled polystyrene (rPS), coconut shell (CS), maleated polystyrene (MAPS) and Ultra-Plast WP516 were compounded using a HAAKE internal mixer and compression molded to form WPC. The effects of material formulation on mechanical, thermal, and morphological properties of the composites were studied. The experiment showed that WPC formulated with 100 phr of rPS, 30 phr of CS, 3 phr of MAPS, and 1 phr of Ultra-Plast WP516 possesses higher modulus and tensile strength compared to the neat EPS, measured at 2.5 GPa and 27.5 MPa, respectively. Although the WPC experienced initiation of thermal degradation at a temperature lower than neat rPS, but the thermal stability of rPS/CS composites containing varying composition of MAPS and Ultra-Plast WP516 was better at high temperature. Furthermore, a 50% weight loss took place at a higher temperature. Nevertheless, the glass transition temperature of the rPS/CS composite with addition of MAPS and Ultra-Plast WP516 was found lower than the neat rPS. POLYM. ENG. SCI., 60:202–210, 2020. © 2019 Society of Plastics Engineers  相似文献   
88.
Wireless Personal Communications - For successful message dissemination in urban vehicular ad hoc networks (VANETs) with reduced route cost and delay is challenging task due to high mobility of the...  相似文献   
89.
This paper deals with the CFD predictions of the three dimensional incompressible flow over a wall mounted cubic obstacle placed in fully developed turbulent flow along with the heat transfer calculations. Reynolds number considered in this study is 1870 based on cube height, h and bulk velocity Ub. Our main objective is to find out the appropriate two equation turbulence model for the complex flow structure which involves recirculation, separation and reattachment. We have used standard kε, low-Reynolds number kε, non-linear kε model, standard kω and improved kω models to solve the closure problem. The non-linear kε model and improved kω models along with standard models are validated with bench mark problem – flow through a backward facing step (BFS). Results showed that the improved kω model is giving overall better predictions of the flow field especially recirculation zone, mean streamwise velocity, and turbulent characteristics when compared to those by standard eddy viscosity models. The non-linear kε model is giving better prediction when compared to standard kε and low Reynolds number kε models. The complex vortex structure around the cube causes large variation in the local convective heat transfer coefficient. The maximum of the heat transfer coefficient occurred in the proximity of the reattachment points and the minimum is found at the recirculation zone.  相似文献   
90.
Accurate estimation of carrier frequency offset (CFO) is an important requirement in orthogonal frequency-division multiplexing (OFDM) based wireless communication systems. In this paper, we propose a hybrid procedure to accomplish this task efficiently. One of the key importance of the approach is the judicious combination of two independent estimators so as to reduce the bandwidth overhead and computational complexity over many conventional methods. It employs the cyclic prefix and a few null subcarriers, respectively, for the fractional and integer frequency offset estimations. We also propose a novel null subcarrier allocation scheme based on Fibonacci series. The range of frequency offset that can be estimated by the proposed technique is equal to the full OFDM bandwidth. Furthermore, performance of the proposed CFO estimator is mathematically analyzed by deriving an expression for the bit error probability of the receiver under Rayleigh fading channel and the Cramer-Rao lower bound for the mean square estimation error. For moderate SNRs, our approach is shown to greatly outperform some recently published methods in terms of BER performance, bandwidth overhead and receiver complexity.  相似文献   
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