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91.
92.
In this paper we describe the synthesis of a novel bichromophoric system in which an efficient photoinduced intercomponent energy transfer process is active. The dyad consists of one subunit of curcumin and one of BODIPY and is able to emit in the far-red region, offering a large Stokes shift, capable of limiting light scattering processes for applications in microscopy. The system has been encapsulated in MCM-41 nanoparticles with dimensions between 50 and 80 nm. Both the molecular dyad and individual subunits were tested with different cell lines to study their effective applicability in bioimaging. MCM-41 nanoparticles showed no reduction in cell viability, indicating their biocompatibility and bio-inertness and making them capable of delivering organic molecules even in aqueous-based formulations, avoiding the toxicity of organic solvents. Encapsulation in the porous silica structure directed the location of the bichromophoric system within cytoplasm, while the dyad alone stains the nucleus of the hFOB cell line.  相似文献   
93.
In many applications, the information required by the user cannot be found in just one source, but has to be retrieved from many varying sources. This is true not only of formatted data in database management systems, but also of textual documents and multimedia data, such as images and videos. We propose a mediator system that provides the end-user with a single query interface to an integrated view of multiple heterogeneous data sources. We exploit the capabilities of the MOMIS integration system and the MILOS multimedia data management system. Each multimedia source is managed by an instance of MILOS, in which a collection of multimedia records is made accessible by means of similarity searches employing the query-by-example paradigm. MOMIS provides an integrated virtual view of the underlying multimedia sources, thus offering unified multimedia access services. Two features are that MILOS is flexible—it is not tied to any particular similarity function—and the MOMIS’s mediator query processor only exploits the ranks of the local answers.  相似文献   
94.
Although there is experimental evidence supporting the involvement of hepatic stem cells in the pathogenesis of liver cancers, the detection and isolation of these cells remains elusive. A logical approach to detecting these cells would take advantage of their ability to differentiate (or to give rise to cells that differentiate) into hepatocytes. This approach requires an assay system that is conducive to hepatocytic differentiation. Here, we report the development of an in vitro system consisting of a three-dimensional collagen gel matrix and a fibroblast feeder layer that supports hepatocytic differentiation from precursor epithelial (oval) cell lines. The LE/2 and LE/6 oval cell lines used in this study are nontumorigenic cells that are derived from the livers of adult rats fed a choline-deficient diet containing 0.1% ethionine for 2 and 6 weeks, respectively. These lines consist of small cells that are phenotypically immature with few cytoplasmic organelles and a high nuclear-to-cytoplasmic ratio. After 4 weeks in the three-dimensional culture system, these cells acquired typical hepatocytic morphology. By electron microscopy, the cells formed canalicular structures that are typical of hepatocytes and were organelle rich, displaying peroxisomes, abundant mitochondria, and rough endoplasmic reticulum. The cells produced albumin and displayed a cytokeratin (CK) pattern typical of hepatocytes (CK 8 and CK 18-positive and CK 19-negative). The presence of a mesenchymal cell feeder layer was essential for supporting hepatocytic differentiation. Without a feeder layer but in the presence of hepatocyte growth factor and/or keratinocyte growth factor, the precursor cells formed ductal structures, suggestive of differentiation along the bile duct lineage. The three-dimensional system described provides direct proof of the lineage generation capacity of oval cells. It offers a model to study factors that may be important for hepatocytic differentiation from precursor cells and a means to assay cell populations for their ability to give rise to normal and transformed hepatocytes.  相似文献   
95.
The overall workplan for assuring the reliability of GaAs MESFETS is presented, as a result of 10 years of industrial experience. The importance of an accurate evaluation of failure mechanisms and acceleration fac-tors is pointed out, describing problems and criticalities related to the reliability testing and the failure analy-sis of this kind of devices. Finally, field data coming from our dynamic data base for system monitoring and surveillance are presented and discussed, demonstrating the satisfactory level of field reliability achieved during last years.  相似文献   
96.
In a prospective longitudinal study, 130 primigravidae at risk for preeclampsia were examined and plasma sampling performed in 45 of them. Plasma thrombomodulin (pTM) was sequentially measured at weeks 12, 24 and 32 of gestation and after delivery in 20 primigravidae who developed either mild preeclampsia (n = 8) or gestational hypertension (n = 12) between weeks 32 and 39 of gestation and in 25 (age-matched) primigravidae who had uneventful pregnancies. pTM elevations were not observed until week 32 in uneventful pregnancies, but were present by week 24 (p = 0.002) in patients who later developed hypertensive complications. A net individual pTM increase > or = 4.2 ng/ml between weeks 12 and 24 (more than 8 times that of normotensive primigravidae) and/or pTM level > or = 47.5 ng/ml at week 32 predicted the development of hypertensive complications with 80% accuracy. Serial pTM determinations can be useful to select pregnancies who may benefit from early pharmacological intervention.  相似文献   
97.
While most life-cycle assessments of buildings have focused on construction and use phases, the location of a building can significantly affect the transportation demand of its inhabitants. The life-cycle energy and greenhouse gas (GHG) emissions of two representative buildings in Lisbon, Portugal, are compared: an apartment building in the city centre and a semidetached house in a suburban area. An integrated approach is used to conduct a life-cycle analysis that includes building construction, building use and user transportation. Sensitivity analyses are used to evaluate impacts for multiple locations. For the apartment, building use accounted for the largest share of energy and emissions (63–64%), while for the house, most (51–57%) of the energy and emissions were associated with user transportation. Energy and GHG emissions for suburban locations were significantly higher (by 55–115%) than those in the city-centre locations, largely due to individuals commuting by car. The analysis demonstrates the significance of transportation and highlights the importance of residence location in urban planning and environmental assessments. These results are likely to apply to other southern European cities that have expanded with significant growth in car ownership and use. To improve urban sustainability, development strategies should consider the transport infrastructure in addition to building efficiency.  相似文献   
98.
The synthesis, in vitro antifungal activity, and molecular docking experiments of some oxime and oxime ether derivatives of azole 1,4-benzothiazine are reported herein, with the aim of evaluating the influence of a partially constrained scaffold that is structurally related to Oxiconazole and bearing the 1,4-benzothiazine moiety, on the inhibition of Candida albicans CYP51.  相似文献   
99.
Real-time adaptive production control in the flexible manufacturing cell (FMC) is a complex issue that needs to be addressed to realize good performance and high productivity. In this paper, we have considered a support vector machine (SVM)-based simulation approach to resolve a production control problem in an FMC that operates in a dynamic environment. A SVM-based simulation approach chooses the most relevant scheduling rule out of several predefined ones on the basis of the current states of the system. This paper examines and compares the performance of the SVM-based simulation approach with the competent scheduling rules under two different operational environments which are characterized by the uncertainty of demand. We have also developed a Visual Basic-based simulation approach for scheduling of component parts in the context of FMC under different situations. The SVM methodology to control the production offers better performance than the single-rule-based production control system.  相似文献   
100.
The aim was to evaluate the effects of different water contents (corresponding to aw 0.940, 0.914, 0.895 and 0.875) of sausages at different times on the characteristics of typical Italian dry fermented sausages packaged under two different modified atmospheres (MAP) (100%N2 or 30%CO2/70%N2). During ripening and storage, samples were analyzed to evaluate pH and aw changes, microbial population, biogenic amine (BA) accumulation and aroma profile.  相似文献   
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