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221.
When cadmium sulphide (CdS) films are deposited using successive ionic layer adsorption and reaction (SILAR) process, a sulphur deficiency defect is always observed. The reason for this defect is addressed in the present work, by systematically analyzing the increasing pattern of Cd2+ions available in the anionic solution bath during the SILAR dipping cycles. The variation of the Cd2+ ion concentration in the anionic solution bath with respect to the number of cycles is analyzed in detail using inductive coupled plasma (ICP) analysis. Moreover, the corresponding sulphur deficiency generated in the CdS thin films is also analyzed using the energy dispersive X-ray analysis profiles, appropriately correlated with the ICP results. The optical transmittance and the thickness measurements are carried out as supplementary studies to support the analysis on the sulphur deficiency. The obtained results may be useful for rectifying this sulfur deficiency defect which is commonly occurred in CdS films deposited using chemical bath deposition as well as SILAR methods.  相似文献   
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223.
Fungal spoilage during refrigerated storage is one of the main safety and quality‐related problems for dairy products. The effect of wheat gluten (WG) and methyl cellulose (MC) biopolymers containing natamycin (NA) on the growth of Aspergillus niger and Penicillium roquefortii on the surface of fresh kashar cheese during storage at 10 °C for 30 days was investigated. Wrapping of A. niger‐inoculated cheese with MC films containing 5–20 mg NA per 10 g resulted in approximately 2‐log reductions in spore count. Two mg NA per 10 g included into WG films was sufficient to eliminate A. niger on the surface of cheese. However, MC and WG films containing NA did not cause any significant decrease in P. roquefortii count on the cheese surface. Therefore, especially use WG films in dairy applications could be an effective way of controlling A. niger growth on these products.  相似文献   
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225.
The identification of semantic relations from a raw text is an important problem in Natural Language Processing. This paper provides semi-automatic pattern-based extraction of part–whole relations. We utilized and adopted some lexico-syntactic patterns to disclose meronymy relation from a Turkish corpus. We applied two different approaches to prepare patterns; one is based on pre-defined patterns that are taken from the literature, second automatically produces patterns by means of bootstrapping method. While pre-defined patterns are directly applied to corpus, other patterns need to be discovered first by taking manually prepared unambiguous seeds. Then, word pairs are extracted by their occurrence in those patterns. In addition, we used statistical selection on global data that is obtaining from all results of entire patterns. It is a whole-by-part matrix on which several association metrics such as information gain, T-score, etc., are applied. We examined how all these approaches improve the system accuracy especially within corpus-based approach and distributional feature of words. Finally, we conducted a variety of experiments with a comparison analysis and showed advantage and disadvantage of the approaches with promising results.  相似文献   
226.
In temporal domains, agents need to actively gather information to make more informed decisions about both the present and the future. When such a domain is modeled as a temporal graphical model, what the agent observes can be incorporated into the model by setting the respective random variables as evidence. Motivated by a tissue engineering application where the experimenter needs to decide how early a laboratory experiment can be stopped so that its possible future outcomes can be predicted within an acceptable uncertainty, we first present a dynamic Bayesian network (DBN) model of vascularization in engineered tissues and compare it with both real-world experimental data and agent-based simulations. We then formulate the question of “how early an experiment can be stopped to guarantee an acceptable uncertainty about the final expected outcome” as an active inference problem for DBNs and empirically and analytically evaluate several search algorithms that aim to find the ideal time to stop a tissue engineering laboratory experiment.  相似文献   
227.
When spent Light Water Reactor fuels are processed by the standard Purex method of reprocessing, plutonium (Pu) and uranium (U) in spent fuel are obtained as pure and separate streams. The recovered Pu has a fissile content (consisting of 239Pu and 241Pu) greater than 60% typically (although it mainly depends on discharge burnup of spent fuel). The recovered Pu can be recycled as mixed-oxide (MOX) fuel after being blended with a fertile U makeup in a MOX fabrication plant. The burnup that can be obtained from MOX fuel depends on: (1) isotopic composition of Pu, which is closely related to the discharge burnup of spent fuel from which Pu is recovered; (2) the type of fertile U makeup material used (depleted U, natural U, or recovered U); and (3) fraction of makeup material in the mix (blending ratio), which in turn determines the total fissile fraction of MOX. Using the Non-linear Reactivity Model and the code MONTEBURNS, a step-by-step procedure for computing the total fissile content of MOX is introduced. As was intended, the resulting expression is simple enough for quick/hand calculations of total fissile content of MOX required to reach a desired burnup for a given discharge burnup of spent fuel and for a specified fertile U makeup. In any case, due to non-fissile (parasitic) content of recovered Pu, a greater fissile fraction in MOX than that in fresh U is required to obtain the same burnup as can be obtained by the fresh U fuel.  相似文献   
228.
The electronic band structure and the total energy of SrX (X=S, Se, Te) in NaCl-type and CsCl-type structures were studied using the tight binding linear muffin-tin orbital method. The calculated ground state properties such as lattice constant and bulk modulus are in agreement with the experimental values. The transition pressures and volumes also agree well with the experimental results. The energy gap at ambient conditions were calculated. The metallization pressures and volumes have also been estimated.  相似文献   
229.
A series of drug-loaded pectin hydrogels were prepared by mixing method in two ion types, Ca+2 or Zn+2, for wound dressing applications and their drug release performances were investigated at pH 6.4 in four different calcium ion concentrations of external solution. Pectin hydrogels were synthesized in three different concentrations of initial pectin solution and theophylline was used as a model drug. Fourier transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy were used for hydrogel characterization. Additionally, fluid handling capacity, swelling behavior, dehydration rate, dispersion characteristic, dressing pH determination, water vapor permeability, oxygen permeability, surface contact angle, flexibility, mass per unit area, and thickness were determined for selected hydrogels. One of the most valuable contributions of our study is that the concentration of initial pectin solution and calcium ion concentration of external solution are very important parameters to obtain an effective drug release. After evaluating all data, we have shown that flexible and transparent pectin-based wound dressings can be synthesized as a controlled drug release system. Zinc-containing hydrogel was antibacterial against Staphylococcus aureus and Escherichia coli but not suitable for cell migration. On the other hand, calcium-based hydrogel was nontoxic on the fibroblast cells and it had no negative effect on cell migration. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48155.  相似文献   
230.
In this study, the potential usage of the Nylon 66 hydrolysis products (HP) for curing “high ortho” novolac resin (N) was investigated. According to FTIR, DSC and TGA results, it is concluded that HP can be as a curing agent for N without the need for another crosslinking agent and thermal degradation stability of cured N-HP blends increased significantly up to 15% HP content. Furthermore, according to performed surface coating tests, it is shown that all films prepared with HP up to 30-wt % have excellent water resistance, drying and adhesion properties as well as with high hardness values.  相似文献   
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