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121.
Involution dependent changes in distribution and localization of bax,survivin, caspase‐3, and calpain‐1 in the rat endometrium 下载免费PDF全文
The endometrial layer of the uterus is characterized by continuous cycle of cell growth and apoptosis in response to hormonal changes. Apoptosis is regulated by several apoptotic regulators, but their significance in involuting uterus has not been well understood. For that reason, aim of this study was to investigate possible role of apoptosis‐related proteins (bax and survivin) and enzymes (caspase‐3 and calpain‐1) in the involuting uterus of the rat, using immunohistochemistry. Our results indicated cytoplasmic and nuclear immunostaining for bax, caspase‐3, calpain‐1 and survivin proteins were found in the endometrial epithelium and stromal cells such as fibroblasts, mast cells and macrophages, and blood vessels; however, calpain‐1 immunoreactivity in the endometrial fibroblast was quite weak or absent. Supranuclear punctate bax immunolabelling was also observed in the endometrial fibroblasts and luminal and glandular epithelial cells from days 1st and 3rd following parturition, respectively. Although survivin was localized in the apical cytoplasm underneath the apical membrane of the luminal epithelium on the 1st and 3rd days, it was also localized in the apicolateral membrane and basal cytoplasm on the 10th and 15th days of involution. Immunostainigs demonstrated that expression patterns of all examined proteins varied with structural changes in the luminal epithelium, and number of immunopositive fibroblasts for bax, caspase‐3 and survivin increased with advance of postpartum days and reached a maximum on postpartum days 10 and 15. These results suggest that the process of postpartum involution of endometrium may be regulated by apoptotic and non‐apoptotic activity of bax, caspase‐3, calpain‐1, and survivin. Microsc. Res. Tech. 79:285–297, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
122.
In the presented work, alpha-benzoin oxime immobilized SP70 chelating resin was synthesized for separation and preconcentration of Pb(II), Cd(II), Co(II) and Cr(III). The optimization procedure for analytical parameters including pH, eluent type, flow rate, etc. was examined in order to gain quantitative recoveries of analyte ions. The effects of foreign ions on the recoveries of studied metal ions were also investigated. The detection limits (3sigma) were found to be 16.0, 4.2, 1.3, 2.4microgL(-1) for Pb, Cd, Co and Cr, respectively. The preconcentration factor was 75 for Pb, 100 for Cd, Co and Cr. The optimized method was validated with certified reference materials and successfully applied to the waters, crops and pharmaceutical samples with good results (recoveries greater than 95%, R.S.D. lower than 10%). 相似文献
123.
Ceren Gürkan Martin Kronbichler Sonia Fernández-Méndez 《International journal for numerical methods in engineering》2019,117(7):756-777
The eXtended hybridizable discontinuous Galerkin (X-HDG) method is developed for the solution of Stokes problems with void or material interfaces. X-HDG is a novel method that combines the hybridizable discontinuous Galerkin (HDG) method with an eXtended finite element strategy, resulting in a high-order, unfitted, superconvergent method, with an explicit definition of the interface geometry by means of a level-set function. For elements not cut by the interface, the standard HDG formulation is applied, whereas a modified weak form for the local problem is proposed for cut elements. Heaviside enrichment is considered on cut faces and in cut elements in the case of bimaterial problems. Two-dimensional numerical examples demonstrate that the applicability, accuracy, and superconvergence properties of HDG are inherited in X-HDG, with the freedom of computational meshes that do not fit the interfaces 相似文献
124.
Using aberration-corrected scanning transmission electron microscopy (STEM), we imaged iridium atoms in isolated iridium complexes in the one-dimensional nonintersecting 14-ring channels of zeolite SSZ-53. STEM allows tracking of the movement of atoms in the channels, demonstrating the interaction of iridium with the zeolite framework (channel confinement) and providing a direct visualization of the initial steps of metal nanocluster formation. The results demonstrate how STEM can be used to help design improved catalysts by identifying the catalytic sites and observing how they change in reactive atmospheres. 相似文献
125.
Atiwongsangthong N 《Journal of nanoscience and nanotechnology》2012,12(8):6602-6607
The purpose of this research, the nanoporous silicon layer were fabricated and investigated the physical properties such as photoluminescence and the electrical properties in order to develop organic vapor sensor by using nanoporous silicon. The Changes in the photoluminescence intensity of nanoporous silicon samples are studied during ultraviolet illumination in various ambient gases such as nitrogen, oxigen and vacuum. In this paper, the nanoporous silicon layer was used as organic vapor adsorption and sensing element. The advantage of this device are simple process compatible in silicon technology and usable in room temperature. The structure of this device consists of nanoporous silicon layer which is formed by anodization of silicon wafer in hydrofluoric acid solution and aluminum electrode which deposited on the top of nanoporous silicon layer by evaporator. The nanoporous silicon sensors were placed in a gas chamber with various organic vapor such as ethanol, methanol and isopropyl alcohol. From studying on electrical characteristics of this device, it is found that the nanoporous silicon layer can detect the different organic vapor. Therefore, the nanoporous silicon is important material for organic vapor sensor and it can develop to other applications about gas sensors in the future. 相似文献
126.
During the Cultural Revolution (1966–1976), scientific work came to a halt in China. Universities closed, primary and secondary school education shut down, and intellectuals (including scientists and engineers) were sent to the countryside or to factories to work. The effects of the Cultural Revolution are reflected in China's output of scientific literature. In 1973, for example, only one Chinese paper appeared in any of the world's 2300 most central journals covered by theScience Citation Index. After restrictive policies were loosened, however, scientific papers grew exponentially. By 1982, only six years after the Cultural Revolution ended, Chinese scientists produced 932 papers. This exponential growth of papers leveled off at this point and the number of papers appearing in the core 2300 journal stood at approximately 1000 in 1983 and 1984. 相似文献
127.
Colloidal boehmite particles have been included into a polyamide-6 matrix by in situ polymerization. The particles have been used without any surface modification. Characterization of the nanocomposites has been carried out using transmission electron microscopy (TEM), dynamical mechanical analysis (DMA) and differential scanning calorimetry (DSC). TEM images indicate that the particles have been homogeneously dispersed in the polymer. DSC results show that the presence of boehmite affects the form of crystallization of polyamide-6, in which case formation of γ-structure is favored over the α-structure and an additional α′-phase is formed. Some mechanical reinforcement of the matrix has been accomplished as indicated by DMA results. The modulus level off at high boehmite concentrations can be explained by the reduction of the crystallinity, which cancels the effect of the filler. 相似文献
128.
129.
The use of unmanned aerial vehicles (UAVs) for military, scientific, and civilian sectors are increasing drastically in recent years. This study presents algorithms for the visual-servo control of an UAV, in which a quadrotor helicopter has been stabilized with visual information through the control loop. Unlike previous study that use pose estimation approach which is time consuming and subject to various errors, the visual-servo control is more reliable and fast. The method requires a camera on-board the vehicle, which is already available on various UAV systems. The UAV with a camera behaves like an eye-in-hand visual servoing system. In this study the controller was designed by using two different approaches; image based visual servo control method and hybrid visual servo control method. Various simulations are developed on Matlab, in which the quadrotor aerial vehicle has been visual-servo controlled. In order to show the effectiveness of the algorithms, experiments were performed on a model quadrotor UAV, which suggest successful performance. 相似文献
130.
Narin Charoenphun Wirote Youravong Benjamas Cheirsilp 《International Journal of Food Science & Technology》2013,48(2):419-428
To manipulate enzymatic hydrolysis of tilapia (Oreochromis niloticus) muscle protein for production of bioactive peptides, its reaction kinetics was intensively studied. The study showed that the production of peptides with different bioactive properties including antioxidant activity, angiotensin‐I‐converting enzyme (ACE) inhibition and Ca‐binding property and their kinetics were affected by the degree of hydrolysis and substrate concentration. A comparative study on reaction kinetics found that the kinetic parameters for the production of each bioactive peptide are unique, that is, the maximum initial velocity, Vmax, for hydrolysis of protein was as high as 1.07 mg mL?1 min?1, but that for the production of peptides with antioxidant activity and Ca‐binding property were very low, range of 7.14–66.7 μg mL?1 min?1, and that for the production of peptides with ACE inhibitory activity was the lowest, at 2.57 μg mL?1 min?1. This knowledge of reaction kinetics of protein hydrolysis would be useful for manipulating and optimising the production of peptides with desired bioactive properties. 相似文献