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101.
The objective of this research was to enhance adsorption capacity of Acacia nilotica (keekar) sawdust for the abatement of chromium bearing wastewater and to investigate the effect of process parameters on adsorption capacity. The sawdust was activated by acid wash and functionalized subsequently with formaldehyde. Functionalization of activated sawdust raised its chromium removal efficiency of almost 10% as compared to its adsorption removal efficiency of HCl treated sawdust in a batch adsorption study. Adsorption kinetic data provided better fitting with pseudo second order model. Maximum adsorption capacity calculated through the best fitting Langmuir model was 6.34 mg·g-1 and 8.2 mg·g-1 for HCl treated and formaldehyde functionalized sawdust adsorbents, respectively. The adsorption of Cr(VI) was endothermic when studied by varying temperature from 20℃ to 50℃ for both activated and functionalized adsorbents.  相似文献   
102.
Gives an impressionistic review of 40 narco-analytic treatments of soldiers who suffered a subacute combat reaction in the 1973 Israel War. The criteria for the application of this treatment are discussed. Narcotherapy is characterized by the intensity of the emotions expressed, leading to problems of transference and countertransference that must be dealt with. Emphasis is placed on the existential aspects encountered in the reliving of traumatic battle experiences. While helping the patient to return to the traumatic past, the therapist simultaneously gives him support derived from the immediate context of the therapeutic dialog. The conclusions drawn from this material can be used as directives for therapists who use narcoanalysis as a form of short-focal psychotherapy. (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
Smart and interconnected devices can generate meaningful patient data and exchange it automatically without any human intervention in order to realize the Internet of Things (IoT) in healthcare (HIoT). Due to more and more online security and data hijacking attacks, the confidentiality, integrity and availability of data are considered serious issues in HIoT applications. In this regard, lightweight block ciphers (LBCs) are promising in resource-constrained environment where security is the primary consideration. The prevalent challenge while designing an LBC for the HIoT environment is how to ascertain platform performance, cost, and security. Most of the existing LBCs primarily focus on text data or grayscale images. The main focus of this paper is about securing color images in a cost-effective way. We emphasis high confidentiality of color images captured by cameras in resource-constrained smartphones, and high confidentiality of sensitive images transmitted by low-power sensors in IoT systems. In order to reduce computational complexity and simulation time, the proposed Lightweight Symmetric Block Cipher (LSBC) exploits chaos-based confusion-diffusion operations at the inter-block level using a single round. The strength of LSBC is assessed by cryptanalysis, while it is ranked by comparing it to other privacy-preserving schemes. Our results show that the proposed cipher produces promising results in terms of key sensitivity and differential attacks, which proves that our LSBC is a good candidate for image security in HIoT.  相似文献   
104.
The ultimate aim of this research is to facilitate the diagnosis of diabetes, a rapidly increasing disease in the world. In this research a genetic programming (GP) based method has been used for diabetes classification. GP has been used to generate new features by making combinations of the existing diabetes features, without prior knowledge of the probability distribution. The proposed method has three stages: features selection is performed at the first stage using t-test, Kolmogorov–Smirnov test, Kullback–Leibler divergence test, F-score selection, and GP. The results of feature selection methods are used to prepare an ordered list of original features where features are arranged in decreasing order of importance. Different subsets of original features are prepared by adding features one by one in each subset using sequential forward selection method according to the ordered list. At the second stage, GP is used to generate new features from each subset of original diabetes features, by making non-linear combinations of the original features. A variation of GP called GP with comparative partner selection (GP-CPS), utilising the strengths and the weaknesses of GP generated features, has been used at the second stage. The performance of GP generated features for classification is tested using the k-nearest neighbor and support vector machine classifiers at the last stage. The results and their comparisons with other methods demonstrate that the proposed method exhibits superior performance over other recent methods.  相似文献   
105.
The previous model for the boundary layer nanofluid flow past a stretching surface with a specified nanoparticle volume fraction on the surface is revisited.The major limitation of the previous model is the active control of the nanoparticle volume fraction on the surface.In a revised model proposed in this paper,the nanoparticle volume fraction on the surface is passively controlled,which accounts for the effects of both the Brownian motion and the thermophoresis under the boundary condition,whereas the Buongiorno’s model considers both effects in the governing equations.The assumption of zero nanoparticle flux on the surface makes the model physically more realistic.In the revised model,the dimensionless heat transfer rates are found to be higher whereas the dimensionless mass transfer rates are identically zero due to the passive boundary condition.It is also found that the Brownian motion parameter has a negligible effect on the Nusselt number.  相似文献   
106.
107.
The objective of this research was to enhance adsorption capacity of Acacia nilotica(keekar) sawdust for the abatement of chromium bearing wastewater and to investigate the effect of process parameters on adsorption capacity. The sawdust was activated by acid wash and functionalized subsequently with formaldehyde.Functionalization of activated sawdust raised its chromium removal efficiency of almost 10% as compared to its adsorption removal efficiency of HCl treated sawdust in a batch adsorption study. Adsorption kinetic data provided better fitting with pseudo second order model. Maximum adsorption capacity calculated through the best fitting Langmuir model was 6.34 mg·g~(-1) and 8.2 mg·g~(-1) for HCl treated and formaldehyde functionalized sawdust adsorbents, respectively. The adsorption of Cr(Ⅵ) was endothermic when studied by varying temperature from 20 °C to 50 °C for both activated and functionalized adsorbents.  相似文献   
108.
A two-group, three-dimensional diffusion theory based methodology coupled with one-dimensional single-phase heat transfer calculations has been developed for the transient analysis of typical material test reactors (MTRs). This methodology has been implemented in a FORTRAN based computer program MTRAP3. It uses the CITATION computer program as a subroutine for static neutronic calculations while the group constant generation is performed by employing the WIMS-D/4 code. The MTRAP3 program uses Cranck–Nicolson (CN) based numerical scheme for solution of time dependant neutron diffusion calculations while time-implicit strategy is employed for detailed heat-transfer calculations. The CN-scheme has been found to remain stable for much larger time steps (Δt ∼ 10−5 s) as compared with the time-explicit scheme which is limited to very small time steps only (Δt ∼ 10−10 s). For step as well as for ramp reactivity induced transients, the predicted values of core integrated reactor power and core average temperatures has been found to agree well with the corresponding values found by using the PARET computer program. The assembly-wise power profile as found by the MTRAP3 program has been found consistent with the corresponding experimental measurements.  相似文献   
109.
Charcoal products can be produced from biomass sources such as charcoal from wood, woody agricultural products, the biogenic fraction of municipal wastes, nut shells, etc. The liquid and gaseous fractions obtained from biomass are a valuable fuel source; however, the solid fraction (charcoal) has the recovery potential of carbon black or as carbon adsorbent after applying an activation step. Charcoal is produced by slow heating wood (carbonization) in airtight ovens or retorts, in chambers with various gases, or in kilns supplied with limited and controlled amounts of air. Charcoal has the potential to improve soil properties, crop productivity, and carbon sequestration in soil. The most interesting temperature range for the production of the pyrolysis products is between 625 and 775 K. The charcoal yield decreased gradually from 43.5 to 31.0% for the walnut shell and from 38.3 to 25.4% for the spruce wood with an increase of temperature from 550 to 1150 K. The charcoal yield decreases as the temperature increases. The ignition temperature of charcoal increases as the carbonization temperature increases. The charcoal briquettes that are sold on the commercial market are typically made from a binder and a filler.  相似文献   
110.
A comparative study of fuel burnup and buildup of actinides and fission products for potential LEU fuels (UO2 and U–9Mo) with existing HEU fuel (UAl4–Al, 90% enriched) for a typical Miniature Neutron Source Reactor (MNSR) has been carried-out using the WIMSD4 computer program. For the complete burnup, the UAl4–Al, UO2 and U–9Mo based systems show a total consumption of 6.89, 6.83 and 6.88 g of 235U, respectively. Relative to 0.042 g 239Pu produced in case of UAl4–Al HEU core, UO2 and U–9Mo based cores have been found to yield 0.793 and 0.799 g, respectively, indicating much larger values of conversion ratios and correspondingly high values of fuel utilization factor. The end-of-cycle activity of the HEU core has been found 2284 Ci which agrees well with value found by Khattab where as for UO2 based and U–9Mo based LEU cores show 1.8 and 4.8% increase with values 2326 and 2394 Ci, respectively.  相似文献   
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