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971.
Lipoxygenase from soybean was encapsulated and the effect of different carrier materials (whey protein, gum arabic, whey protein along with sodium alginate and maltodextrin) on enzyme stability during spray drying was studied and compared with freeze drying. The addition of polyethylene glycol (PEG-4000) during spray drying evidently enhanced enzyme stability. Total activity of lipoxygenase after spray drying was 1.14 × 104(whey protein isolate), 1.2 × 104(gum arabic), 1.09 × 104 (whey protein isolate + sodium alginate), 1.44 × 104(maltodextrin), and 1.55 × 104(PEG + maltodextrin). Highest enzyme activity recovery of 72.02% was achieved with the combined addition of maltodextrin and PEG-4000. Moisture, scanning electron microscopy analysis, and storage studies were carried out for spray- and freeze-dried enzyme. 相似文献
972.
B.M. Choudary N. Sreenivasa Chowdari M. Lakshmi Kantam P. Lakshmi Santhi 《Catalysis Letters》2001,76(3-4):213-218
Heterogeneous Mn(III) chiral salen complexes are prepared through covalent attachment of salen ligand on silica gel via chloropropyl spacer and subsequent complexation with manganese. The complexes are well characterized by IR, UV/VIS, TGA and elemental analysis. Epoxidation of unfunctionalised prochiral olefins by Mn(III) chiral salen complexes using iodosobenzene and m-CPBA as the terminal oxidants and NMO as a co-oxidant was achieved with good yields albeit low enantiomeric excess. 相似文献
973.
Removal of water from the crude petroleum during its extraction and refining process is one of the major problems faced by petroleum industries, so in this study a superabsorbent has been synthesized from Psyllium and acrylic acid based polymers under the influence of gamma radiations using hexamine as a crosslinker. After optimizing various reaction parameters, the optimized superabsorbent has been tested for its selective water absorption capacity from different oil–water emulsions as a function of time, temperature, pH, and NaCl concentration. The synthesized superabsorbent has been found to be highly selective toward water absorption with maximum percent swelling of 8560% in petrol–water emulsion. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
974.
Judith A. Brown Lakshmi J. Vendra Afsaneh Rabiei 《Metallurgical and Materials Transactions A》2010,41(11):2784-2793
The performance of new composite metal foams (CMFs) under bending was evaluated with simultaneous acoustic emission (AE) monitoring on samples processed by cast and powder metallurgy (PM) techniques. The results showed high maximum strength in all samples up to 86 MPa with more ductile failure in PM samples. Acoustic emission behavior confirmed that the dominating failure mechanism of cast CMF is the brittle fracture of intermetallic phases that mostly exist at the interface of the steel spheres with the aluminum matrix, whereas in PM samples (100 pct steel), the failure is governed by the propagation of preexisting microporosities in the matrix resulting in a complete ductile failure. SEM imaging of the fracture surfaces supported these findings. 相似文献
975.
ABSTRACT Image super-resolution (SR) techniques aim to estimate high-resolution (HR) image from low-resolution (LR) image. Existing SR method has slow convergence and recovery of high-frequency details are inaccurate. To overcome these issues, two algorithms have been proposed for image SR based on non-local means improved iterative back projection (NLM-IIBP), deep convolutional neural network improved iterative back projection (DCNN-IIBP) to produce high-resolution images with low noise, minimal blur by restoring high-frequency details. In NLM-IIBP denoised images have been interpolated using cubic B-spline interpolation and processed using IIBP based on guided bilateral method. NLM preserves the edges effectively, but does not consider high dimensional information and over smoothing during noise minimization. To further improve the resolution, NLM is replaced by DCNN. DCNN denoising method suppresses different noises at different noise levels. The proposed algorithms have been analysed and compared with existing approaches using various parameters to prove the effectiveness. 相似文献
976.
R. Anbarasan J. Jayaseharan M. Sudha J. Lakshmi Devi P. V. Nirmala A. Gopalan 《应用聚合物科学杂志》2001,81(2):468-478
Oxidative chemical polymerization of aniline was carried out using peroxydisulphate and peroxomonosulphate as a lone initiator in an aqueous acidic medium in the presence of Rayon fiber. The Rayon fiber was tested for the chemical grafting of polyaniline onto it. The content of polyaniline (wt %) in the backbone was found to vary while varying the [M], [I], and (amount of Rayon fiber) during the polymerization of aniline. Various graft parameters like rate of grafting, % grafting, and % efficiency were calculated. Rate of homopolymerization was also followed for both cases. The chemical grafting was confirmed using FTIR spectroscopy, cyclic voltammetry, weight loss study, and conductivity measurements. Probable mechanism has been proposed to explain the experimental results obtained. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 468–478, 2001 相似文献
977.
The implementation of three parallel sorting algorithms, namely binary sort, odd-even transposition sort and bitonic sort, on a network of transputers is analysed in the paper. The variation in the performance of these algorithms as the number of processors and sort size are changed is investigated. Experimental results show that when up to eight transputers are used, connected as a linear pipeline configuration, all three algorithms can achieve reasonable speedup ratios. The bitonic sort, binary sort odd-even transposition sort achieve speedup ratios of 5, 4.4 and 4, respectively, when eight processors are used to sort 100,000 integers. Analytical models are derived which can be used to predict the performance of the three algorithms when a linear pipeline configuration is used. The predicted performance of the algorithms is compared with the experimental performance in order to validate the model. When the models are used to predict the performance using 16 transputers, it is found that the speedup does not significantly improve compared to the performance achieved with eight transputers. This shows that interprocessor communication has a significant effect on the algorithmic performance when a larger number of processors are used. The conclusions reinforce the fact that the binary and bitonic sorting algorithms are not well-suited to a linear pipeline configuration and that they may perform better if a different topology were used, for example a mesh or a cube connection scheme. Further, the analytical technique used for performance modelling as elaborated in the paper can be employed profitably for other multiprocessor systems as well. 相似文献
978.
Nadeem Hussain Mehwish Kiran Zongyan Gao Linbin Tang Junjian Li Pengyu Gao Zuofeng Chen Fengting Li Tao Liu 《Advanced functional materials》2024,34(10):2310805
Transition-metal selenides are considered as one of the promising anode materials for potassium ion batteries (PIBs) due to their high theoretical capacities. However, addressing the issue of irreversibility caused by the large volume changes during potassiation/depotassiation, especially at high rates, remains a major challenge. This challenge is tackled by constructing nickel-iron selenide (NFS) with a unique hierarchically porous donut-like morphology using a simple template-free solvothermal strategy. With the bimetallic strategy and well-designed architecture, the donut-like NFS displays outstanding potassium storage performance, exhibiting a high reversible capacity (458 mAh g−1 even after 100 cycles at a slow rate of 0.1 A g−1), an impressive rate capability up to 10 A g−1 (≈10 mA cm−2), and an excellent capacity retention over 1000 cycles at 2 A g−1. By combining theoretical and experimental techniques, a two-stage intercalation-conversion reaction mechanism is put forward. This work provides an effective approach to develop bimetallic selenides electrode materials for applications in PIBs and potentially for other energy storage devices. 相似文献
979.
The polycrystalline samples of Ba5BiTi3Nb7O30 (hereafter BBTN) belonging to ferroelectric oxide family of tungsten bronze structure were prepared by high temperature solid-state reaction method. Preliminary X-ray analysis of the samples provided the lattice parametersa=11·9331 Å,b=14·9684 Å, andc=7·0193 Å, and also formation of a single-phase orthorhombic structure at room temperature (303 K). Detailed studies of dielectric constant (ε) and loss (tanδ) as a function of frequency (500 Hz to 10 KHz) at room temperature and also as a function of temperature (liquid nitrogen to 160°C) show the dielectric anomaly and structural phase transition at 16·8°C. 相似文献
980.
Abdul Qadeer Dayo Li-li Zhang Jun Wang Wen-bin Liu Sadia Kiran Abdeldjalil Zegaoui Hamid Abdelhafid Ghouti Yitagesu Bereket Arse 《应用聚合物科学杂志》2020,137(4):48313
The bisphthalonitrile (PN) thermosets series (poly(Baph), poly(Bafph), and poly(Bzph)) were prepared and subjected to 100 and 500 kGy γ-ray irradiation dose from cobalt-60 (60Co) as a source. The main objective of this present study was to investigate the effects of gamma irradiation on the chemical structure, thermomechanical, mechanical, and thermal stabilities, which were studied by using a Fourier transform infrared (FTIR), dynamic mechanical analysis, bending test, and thermogravimetric analysis, respectively. The PN resins characteristics bands, namely, nitrile, triazine ring, and phthalocyanine, were not affected on γ-ray irradiation. However, remarkable changes were observed in the chemical structures of benzene, alkyl and CF3, which indeed slightly declined the thermal stabilities, thermomechanical and flexural properties. The decrease in properties could be ascribed to the scission of molecular chains and rupture of chemical bonds of PN resin as confirmed by the FTIR. The poly(Bafph) showed a maximum decline in the thermal stabilities and mechanical properties due to the existence of CF3 in the polymer skeleton, which could not be crosslinked again once scission occurs under radiation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48313. 相似文献