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91.
Whole dead poultry birds obtained from commercial layer farms were assessed for fat in the whole carcass and then dry rendered in three different rendering regimens T1, T2 and T3 (temperature = 120, 130 and 140 °C and shell pressure = 1, 2 and 3 kg/cm2 respectively) and the effect on the yield and quality of the rendered chicken oil were studied. The overall fat percentage of the whole dead poultry carcass was 14.55 ± 0.17 % and the fat content of ‘greaves’ was 14.49 ± 0.38 %. In the dry batch rendering trials, the mean overall fat recovery was 24.46 ± 1.19, 26.78 ± 3.14 and 22.42 ± 2.32 % and the overall fat yield was 3.52 ± 1.72, 3.84 ± 0.44 and 3.22 ± 0.33 % of the carcass weight in T1, T2 and T3 respectively. Solvent extraction of fat could recover 96.10 ± 0.14 % of fat from ‘greaves’ which was significantly higher than the mechanical centrifugation method. Among the quality characteristics of the rendered chicken oil (RCO), moisture content ranged from 0.61 % (T2) to 1.09 % (T1) and the mean specific gravity was 0.91 at 30 °C. The FFA values of RCO obtained from the T3 rendering regimen were significantly (p < 0.05) higher than the FFA values of T2 and T1. The mean acid value, iodine number, peroxide value, saponification value and unsaponifiable matter present in RCO showed no significant difference. The fatty acid profile and calorific values were studied. The RCO was converted to biodiesel by transesterification and the physico-chemical properties of the biodiesel were studied and compared with the Indian biodiesel specification.  相似文献   
92.
Summary Composites of carbon a nanotube with polymers are a developing and interesting area of research. The dispersion of the nanotube in polymer matrices is an important factor while making its nanocomposites. Even though in-situ polymerization approach offers a better approach for synthesizing homogeneous polymer nanotube composites, the dispersion of the nanotubes in the monomer solution is a problem. In this article we report a new chemical method for dispersing nanotubes in monomer and the preparation of uniform tubular composite of polyaniline (PANI) and multiwalled carbon nanotube (MWNT). For this the oxidized multiwalled nanotube (o-MWNT) was functionalized with p-phenylenediamine, which gave phenylamine functional groups on the surface. This functionalization helped to disperse the nanotubes in acidic solution. The in-situ polymerization of aniline in the presence of these well dispersed nanotubes gave a new tubular composite of carbon nanotube having an ordered uniform encapsulation of doped polyaniline. The phenylamine functional groups on the surface were grown into polyaniline chain so that the composite contains polyaniline functionalized CNT and they were no more an impurity in the final nanocomposite. The microscopic and structural properties of this composite were compared with that of a composite prepared under identical condition using o-MWNT.  相似文献   
93.

In this paper, Reduced Graphene Oxide (rGO)/ZnFe2O4 (rZnF) nanocomposite is synthesized by a simple hydrothermal method and employed as a counter electrode (CE) material for tri-iodide redox reactions in Dye sensitized solar cells (DSSC) to replace the traditional high cost platinum (Pt) CE. X-ray diffraction analysis and High resolution Transmission electron microscopy, clearly indicated the formation of rZnF nanocomposite and also amorphous rGO sheets were smoothly distributed on the surface of ZnFe2O4 (ZnF) nanostructure. The rZnF-50 CE shows excellent electro catalytic activity toward I3? reduction, which has simultaneously been confirmed by cyclic voltammetry, electrochemical impedance spectroscopy and Tafel polarization measurements. A DSSC developed by rZnF-50 CE (η?=?8.71%) obtained quite higher than the Pt (η?=?8.53%) based CE under the same condition. The superior performances of rZnF-50 CE due to addition of graphene in to Spinel (ZnF) nanostructure results in creation of highly active electrochemical sites, fast electron transport linkage between CE and electrolyte. Thus it’s a promising low cost CE material for DSSCs.

  相似文献   
94.
Oil migration in filled pralines is a phenomenon that is highly correlated with the occurrence of chocolate bloom. In this study the potential to suppress or prevent oil migration by incorporation of sterol/sterolster-structured organogels was evaluated. Different quantities, 2.5 or 14% (w/w), of gel with structurant levels of either 10 or 25% (w/w) were studied in a layered model system. The gel was either a part of the nougat or of the chocolate phase, or as a separate layer. Samples were monitored regularly for a period of 24 weeks at storage temperatures of 10, 18 and 28 °C. The amount of migrated oil was determined via DSC analysis of a surface sample. The results indicate that, despite the additional oil brought into the system via the oleogel, the level of oil found in the chocolate layer is reduced through the presence of the gel. In particular, the three-layer system and gelled chocolate appear to be promising routes to either suppress oil migration or improve nutritional profiles by incorporation of liquid oils.  相似文献   
95.
This paper presents the design, fabrication, and experimental results of a 1 : 4 monolithic power distribution network for Ku-band array antenna applications. The network integrated on a high-resistivity silicon (HRS) substrate surface stabilized by polysilicon consists of three Wilkinson power dividers, four dc blocking filters, and four coplanar waveguide (CPW)-to-microstrip (MS) transitions. Each output ports are fed with a barium-strontium-titanate phase shifter. It is found that the introduction of the polysilicon layer between the oxide and HRS reduces RF losses significantly, which will enable the monolithic integration of high-power controller modules onto silicon because of the existence of the oxide layer, preventing any degradation of RF performances. The individual components show insertion losses ranging from 0.4 to 2.6 dB at 15 GHz, and the interconnecting CPW lines result in a loss of 0.064 dB/mm. This network was successfully integrated with MS patch antennas monolithically, showing good performance of 32-dB return loss at 14.85 GHz, and 10/spl deg/ beam-steering capability.  相似文献   
96.
This study examines the relationships between care felt and engagement in innovative behaviors at work. We posit that when an individual perceives that coworkers care for him or her (i.e., care felt), this cultivates psychological conditions such as safety, meaningfulness, and availability, which result in a higher level of motivation and by implication engagement in innovative behaviors at work. A sample of 218 employees took part in the assessment of the relationship between the psychological conditions linked to care felt (measured at Time 1) and motivation and engagement in innovative behaviors (measured at Time 2). The results of structural equation modeling (SEM) indicate that care felt is positively linked to psychological conditions. The latter is positively related directly and indirectly (through motivation) to engagement in innovative behaviors. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
97.
Dekel B  Katzir A 《Applied optics》2002,41(18):3622-3627
We have developed waveguides for the mid-IR spectrum using silver halide crystals. Diffused planar waveguides constructed from silver chlorobromide (AgClBr) with different diffusion thicknesses were designed and characterized. The waveguides were based on our changing the refractive index of the guiding layer by a diffusion of Br- ions into crystalline AgCl substrates. The waveguides were analyzed and investigated with a 10.6-microm CO2 laser, and the optically measured thicknesses of the waveguides were found to vary between 65 and 600 microm. The propagation losses were in the range of 4-16 dB/cm, and the maximal entrance angle was 62 degrees. The output beam distribution was measured and was in good correlation with a numerical analysis simulation based on a ray-tracing model, by use of the eikonal equation.  相似文献   
98.
99.
Research in accelerated pavement testing (APT) facilities has traditionally focused on the pavement performance such as rutting and fatigue cracking, but documentation on construction management and information of the actual pavement construction quality is limited. There are typically four critical factors that need to be considered to achieve the best possible outcome in construction: cost, schedule, construction process, and quality control, and management. With the objective of developing guidelines for planning and executing construction of a small-scale APT facility, this paper presents a case study documenting and evaluating the construction process and construction management efforts of two sensor-instrumented hot mix asphalt pavement test sections built in a small-scale APT facility. The focus of the experiment was to study bottom-up fatigue cracking of the flexible pavement structure. The presented information and lessons learned serve as a template and guide for agencies pursuing this type of research and pavement construction.  相似文献   
100.
The Rational Unified Process is a comprehensive process model that is tailorable, provides templates for the software engineering products, and integrates the use of the Unified Modeling Language (UML); it is rapidly becoming a de facto standard for developing software. The process supports the definition of requirements at multiple levels. Currently, the early requirements, or goals, are captured in a textual document called the Vision Document, as the UML does not include a goal modeling diagram. The goals are subsequently refined into software requirements, captured in UML Use Case Diagrams. Given the well documented advantages of visual modeling techniques in requirements engineering, including the efficient communication and understanding of complex information among numerous diverse stakeholders, the need for an enhanced version of the Vision Document template which supports the visual modeling of goals is identified. Here, an Enhanced Vision Document is proposed which integrates two existing visual goal models: AND/OR Graph for functional goals and Softgoal Interdependency Graph for non-functional goals. A specific approach to establishing traceability relationships from the goals to the Use Cases is presented. Tool support has been developed for the Enhanced Vision Document template; the approach is illustrated using an example system called the Quality Assurance Review Assistant Tool.  相似文献   
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