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61.
The application of computationally inexpensive modeling methods for a predictive study of powder mixing is discussed. A multidimensional population balance model is formulated to track the evolution of the distribution of a mixture of particle populations with respect to position and time. Integrating knowledge derived from a discrete element model, this method can be used to predict residence time distribution, mean and relative standard deviation of the API concentration in a continuous mixer. Low‐order statistical models, including response surface methods, kriging, and high‐dimensional model representations are also presented. Their efficiency for design optimization and process design space identification with respect to operating and design variables is illustrated.

  相似文献   

62.
Grain boundary sliding during high temperature deformation can lead to stress concentrations and an enhancement of diffusion in mobile boundaries. Experiments were conducted on a fine grained 3 mol% yttria stabilized tetragonal zirconia, under conditions associated with superplastic flow involving grain boundary sliding. Tracer diffusion studies under creep conditions and without load indicate that there is no enhancement in either the lattice or grain boundary diffusivities. The experimental creep data are consistent with an interface controlled diffusion creep mechanism.  相似文献   
63.
Structure–activity relationship studies were conducted on Irosustat (STX64, BN83495), the first steroid sulfatase (STS) inhibitor to enter diverse clinical trials for patients with advanced hormone‐dependent cancer. The size of its aliphatic ring was expanded; its sulfamate group was N,N‐dimethylated, relocated to another position and flanked by an adjacent methoxy group; and series of quinolin‐2(1H)‐one and quinoline derivatives of Irosustat were explored. The STS inhibitory activities of the synthesised compounds were assessed in a preparation of JEG‐3 cells. Stepwise enlargement of the aliphatic ring from 7 to 11 members increases potency, although a further increase in ring size is detrimental. The best STS inhibitors in vitro had IC50 values between 0.015 and 0.025 nM . Other modifications made to Irosustat were found to either abolish or significantly weaken its activity. An azomethine adduct of Irosustat with N,N‐dimethylformamide (DMF) was isolated, and crystal structures of Irosustat and this adduct were determined. Docking studies were conducted to explore the potential interactions between compounds and the active site of STS, and suggest a sulfamoyl group transfer to formylglycine 75 during the inactivation mechanism.  相似文献   
64.
We describe the etch processes used for integration of embedded ferroelectric random access memory (FRAM) within a standard CMOS logic flow. The ferroelectric module is inserted following front-end contact formation and prior to backend integration using only two additional mask levels: capacitor pattern and bi-level via pattern. The single-mask stack etch process employs a TiAlN hardmask to define Ir/IrOx/PZT/IrOx/Ir capacitors. Protective sidewalls can be formed using an etchback process. The bi-level via etch and subsequent metal fill processes complete the FRAM module formation. Functional 4 MB arrays embedded with 5 levels of Cu/FSG integration have been demonstrated.  相似文献   
65.
In order to make the judicious use of thiram fungicide we have developed starch- and alginate-based controlled and sustained agrochemical delivery system in the form of beads using calcium chloride (CaCl2) as crosslinker. The beads were characterized by FTIR and swelling studies. To study the effect of composition of the beads on the release dynamics of fungicide (thiram), beads were prepared by varying the amount of starch, alginate and crosslinker in the beads. Formulation characteristics like entrapment efficiency, bead size, percentage equilibrium swelling of the beads and diffusion mechanism for thiram release have been evaluated. Maximum (93.33+/-2.89)% swelling and maximum (80.67+/-0.83)% thiram release has occurred in the beads prepared with 15% starch, 1% alginate and 0.1M crosslinker solution. In most of the formulations the entrapment efficacy of thiram has been observed more than 90% and the values for the diffusion exponent 'n' have been obtained >1 which shows that the release of fungicides occurred through Case II diffusion mechanism.  相似文献   
66.
In this paper, the impact of extra electron source (EES) and dual metal gate engineering on conventional charge plasma TFET (CP-TFET) have been done for improving DC and analog/RF parameters. CP-TFET structure is upgraded to double source CP-TFET (DS-CP-TFET) by placing an EES below the source/channel junction for enhancing the device performance in terms of driving current and RF figures of merit (FOMs). But, in spite of these pros, the approach is having cons of higher leakage current similar to MOSFET and negative conductance (inherent nature of TFET). Both the issues have been resolved in the double source dual gate CP-TFET (DS-DG-CP-TFET) by gate workfunction engineering and drain underlapping respectively. Additionally, for getting the optimum performance of DS-DG-CP-TFET, the device sensitivity has been investigated in terms of position of EES, length of drain electrode and workfunction of gate electrode 1 (GE1).  相似文献   
67.
In the existent paper, the performance of thermal storage hybrid buildings exploiting the latent heat of phase change materials (PCMs) for thermal refrigeration and heating of the contemporary period has been investigated. The conventional buildings consume a large amount of electricity, primarily for the heating and cooling applications. Electricity generation primarily relies on coal-based thermal power plants. The emissions from these establishments pose a serious threat to the environment. Moreover, conventional heating/cooling units rely on exorbitant energy cost. The usage of any kind of thermal storage system is an efficacious way of stockpiling thermal energy and utilizing it when needed. This paper gives a comprehensive overview of the available thermal storage units incorporating PCMs. The various segments of the buildings, viz, ceiling, window, wall, and floor have been analyzed in details. The results are quite promising in terms of load reduction and overall energy saving. Indoor surface temperature reduction of up to 7oC has been achieved. The energy saving of up to 40% can be realized by employing PCM. A comprehensive list of the PCMs is also tried to build up for end users according to their temperature requirement.  相似文献   
68.
The study aimed to investigate the utilisation of prebiotic D-tagatose by probiotic lactobacilli (Lrhamnosus GG, Lcasei, Lacidophilus and Lfermentum) and enteric pathogens (E. coli and S. typhimurium) to determine synbiotic potential of D-tagatose and lactobacilli combination. The antimicrobial efficacy of the synbiotic preparations (D-tagatose with lactobacillus) was assessed against selected pathogens in co-culture assays. Evidently, D-tagatose supported growth of selected lactobacilli, especially the L. rhamnosus GG and L. casei, but not the enteric pathogens. The tested synbiotic preparations completely inhibited growth of both the pathogens, even in the presence of D-glucose in co-cultures. The well-diffusion assay demonstrated the presence of antimicrobial activity as recorded by drop of culture pH. The study substantiated that D-tagatose could be an effective prebiotic component for formulation of potential synbiotic combinations with L. rhamnosus GG or L. casei that can be used as an alternative to antibiotics against enteric pathogens.  相似文献   
69.
Experiments were conducted on a superplastic copper alloy to investigate the growth of single holes machined in the gage length prior to testing. Specimens were deformed in tension in the three regions of flow associated with superplastic materials. Within each flow region, three distinct stages of hole growth were identified. Initially, in stage 1, the hole simultaneously increases in length along the tensile axis but decreases in the dimension measured perpendicular to the tensile axis (“transverse contraction”). Subsequently, in stage 2, the hole grows both along and perpendicular to the tensile axis (“transverse growth”). Finally, in stage 3, a crack nucleates on either side of the hole and propagates to cause failure (“crack propagation”). It is shown that the transitions between the different stages of growth is dependent upon the initiation and development of macroscopic necking adjacent to the hole.  相似文献   
70.
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