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91.
Past research has found that recipients agree with majority group positions and resist minority group positions on direct measures of influence. The authors suggest that these attitude shifts reflect normative pressures to align with valued majorities and to differentiate from derogated minorities. In support of this idea, participants who considered a majority group relevant to their own self-definitions (but not those who judged it irrelevant), on learning that the group held a counterattitudinal position, shifted their attitudes to agree with the source. In a second study, recipients who judged a minority group (negatively) self-relevant, on learning that the group held a similar attitude to their own, shifted their attitudes to diverge from the source. These shifts in attitudes were based on participants' interpretations of the attitude issues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
Computer systems are increasingly being used for sports training. Existing sports training systems either require expensive 3-D motion capture systems or do not provide intelligent analysis of user’s sports motion. This paper presents a framework for affordable and intelligent sports training systems for general users. The user is assumed to perform the same type of sport motion as an expert, and therefore the performer’s motion is more or less similar to the expert’s reference motion. The performer’s motion is recorded by a single stationary camera, and the expert’s 3-D reference motion is captured only once by a commercial motion capture system. Under such assumptions, sports motion analysis is formulated as a 3-D–2-D spatiotemporal motion registration problem. A novel algorithm is developed to perform spatiotemporal registration of the expert’s 3-D reference motion and a performer’s 2-D input video, thereby computing the deviation of the performer’s motion from the expert’s motion. The algorithm can effectively handle ambiguous situations in a single video such as depth ambiguity of body parts and partial occlusion. Test results on Taichi and golf swing motion show that, despite using only single video, the algorithm can compute 3-D posture errors that reflect the performer’s actual motion error.  相似文献   
93.
Corpus based speech synthesis can produce high quality synthetic speech due to it high sensitivity to unit context. Large speech database is embedded in synthesis system and search algorithm (unit selection) is needed to search for the optimal unit sequence. Speech feature which served as target cost is estimated from the input text. The acoustic parameters which served as join cost are derived from mel frequency cepstral coefficients (MFCCs) and Euclidean distance. In this paper, a new method which is Genetic Algorithm is proposed to search for optimal unit sequence. Genetic Algorithm (GA) is a population based search algorithm that is based on the biological principles of selection, reproduction, crossover and mutation. It is a stochastic search algorithm for solving optimization problem. The speech unit sequence that has minimum join cost will be synthesized into complete waveform data.  相似文献   
94.
Photothermal steam generation promises decentralized water purification, but current methods suffer from slow water evaporation even at high photothermal efficiency of ≈98%. This drawback arises from the high latent heat of vaporization that is required to overcome the strong and extensive hydrogen bonding network in water for steam generation. Here, light-to-vapor conversion is boosted by incorporating chaotropic/kosmotropic chemistries onto plasmonic nanoheater to manipulate water intermolecular network at the point-of-heating. The chaotropic-plasmonic nanoheater affords rapid light-to-vapor conversion (2.79 kg m−2 h−1 kW−1) at ≈83% efficiency, with the steam generation rate up to 6-fold better than kosmotropic platforms or emerging photothermal designs. Notably, the chaotropic-plasmonic nanoheater also lowers the enthalpy of water vaporization by 1.6-fold when compared to bulk water, signifying that a correspondingly higher amount of steam can be generated with the same energy input. Simulation studies unveil chaotropic surface chemistry is crucial to disrupt water hydrogen bonding network and suppress the energy barrier for water evaporation. Using the chaotropic-plasmonic nanoheater, organic-polluted water is purified at ≈100% efficiency, a feat otherwise challenging in conventional treatments. This study offers a unique chemistry approach to boost light-driven steam generation beyond a material photothermal property.  相似文献   
95.
Several methods of ascertaining and classifying childhood neoplasms for epidemiological study have been evaluated using material from the University of Manchester Children's Tumour Registry (CTR), which includes data from several sources on children with neoplasms first seen in the period 1954-73 who were under 15 years old and living in the Manchester Regional Hospital Board area at the time. Two systems of classification-the International Classification of Diseases (ICD) and the Morphology Section of the Manual of Tumor Nomenclature and Coding (MOTNAC; Percy, Berg and Thomas, 1968)-were tested. No major problems arose with the Morphology Section of MOTNAC, and we recommend that the revised version of this section, in the proposed "International Classification of Diseases for Oncology", should be used in epidemiological reports on children's tumours whenever possible. The ICD discriminates less well between the commoner types of childhood neoplasms, but must be retained as a supplementary classification to facilitate international comparisons. A comparison of the completeness of ascertainment achieved in recent years by each source of data showed that more than 98% of the serious cases (neoplasms that were malignant and/or lay within the craniovertebral canal) could have been identified using a combination of Hospital Activity Analysis (HAA) and cancer registration records, and more than 95% using HAA and death records. But in an analysis of 2 years' HAA returns and 6 years' cancer registrations of serious cases, nearly one quarter of the former and one fifth of the latter were shown to record diagnoses which differed from those finally assigned at the CTR. It is concluded that, in epedimiological studies based on routine records, the diagnoses given should always be checked centrally, by experts, in the light of all the available clinical and pathological material (including histological preparations).  相似文献   
96.
The supermolecular structure and viscoelastic and diffusion properties of a perfluorinated polymer containing sulfonic acid (Nafion) were investigated. The breakdown of time–temperature super-position for the dry salt and and acid in the presence of 0.5 H2O/SO3H as well as the results of small-angle x-ray scattering suggest that the ions in this material are clustered. Above 180°C, the reestablishment of the time–temperature superposition in the salt suggests that ions in the clusters become mobile. Dynamic mechanical studies were performed over a temperature range from ?190°C to above the glass transition temperatures Tg of the materials. The Tg of the salts is found at ca. 220°C, while in the acid it occurs at 110°C. A β peak in the acid is found at ca. 20°C, while in the salts it occurs between 140°C and 160°C. The β peak shifts to a lower temperature with the addition of water in both the acid and the salts, while the α and γ peaks are unaffected. The latter is located at ca. ?110°C at 1 Hz. Dielectric behavior has also been studied as a function of water content for the acid sample and the potassium salt at frequencies of 100 Hz to 10 kHz. Two relaxations with different activation energies were observed. The position of both peaks shifts to a lower temperature as the water content increases. Finally, the diffusion of water in Nafion in the acid form has been determined. The diffusion coefficient can be represented by the equation   相似文献   
97.
Extraction is a mandatory process for most of the industries, especially in the food processing industry to obtain the targeted compounds from various sources such as plant or seed samples. This review paper provides information about various extraction techniques that are normally used in the edible oil extraction industry. Five extraction techniques are presented in this paper. Among all the techniques presented in this paper, pressing and solvent extraction methods are considered as traditional techniques while supercritical fluid extraction, microwave assisted extraction, and ultrasound assisted extractions are considered as advanced techniques. Both advantages and disadvantages of supercritical fluid extraction, microwave assisted and ultrasound assisted extractions are discussed. Furthermore, the parameters that would affect the output of each technique are included in each section. Nowadays, research is going on to further enhance the extraction method to obtain a higher extraction yield or increase the quality of the extraction product. The enhancement can be either combining two or more extraction techniques into one complete process or modifying the available technique alone. Therefore, the theoretical knowledge provided in this review will be useful for future researchers who are interested in enhancing the extraction techniques. Practical Applications : Extraction is a mandatory process in edible oil extraction industry. Extraction industry is always looking for a process which is high efficiency and low extraction cost. Therefore, various advanced techniques or treatments are applied to optimize the oil yield and shorten the extraction time. This paper provides a review on various techniques by summarizing both advantages and disadvantages of each technique. The information can be very useful for improving the current extraction technique to further optimize the oil yield or enhance the quality of oil.  相似文献   
98.
A new approach for artificial photocatalysis of electrical generation directly from atmospheric water is reported. A hybrid system comprising a hydrogel incorporated with Cu2O and BaTiO3 nanoparticles is developed, wherein the Cu2O is designed to expose two different crystal planes, namely (100) and (111). These planes exhibit different surface potentials and form a polarization electric field of 2.3 kV cm?1 that acts on a ferroelectric dipole. With the help of this electric field, the dipole is redirected for aiding in positive and negative polarizations with (100) and (111) planes, then boosting water reduction and oxidation kinetics separately at (100) and (111) planes. Additonally, zinc‐/cobalt‐based superhygroscopic hydrogels serve as a water‐capturing “hand” to harness humidity from the ambient environment. The integrated hydrogel–Cu2O@BaTiO3 hybrid is used to dehumidify air, which can split 36.5 mg of water by employing only 150 mg hydrogel and simultaneously generate a photocurrent of 224.3 µA cm?2 under 10 mW cm?2 illumination.  相似文献   
99.
Low levels of functional acrylic monomers were incorporated into a core‐shell acrylic copolymer by seeded emulsion polymerization. The increase in glass transition temperature, Tg, from DSC measurement has showed that although certain amount of crosslinking reactions have occurred during the polymerization and isolation of the copolymer, the dried copolymer films could undergo further curing by UV irradiation. The structure and amount of the functional monomer, concentration of photoinitiator, and the extent of UV exposure have exerted significant influence on the Tg of the dry copolymer films. Because of the relatively low level of incorporated unsaturation, there was no significant change in FTIR during the curing of the film. Further, crosslinking of the copolymer film induced by UV irradiation has significantly increased the resistance to swelling in alkaline solution, although the gel content remained the same. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2317–2322, 2006  相似文献   
100.
B.W. Cherry  Teoh Swee Hin 《Polymer》1983,24(8):1067-1070
A technique involving the use of a three-element mechanical model with a critical stored energy criterion modelled accurately the creep rupture time of two types of high-density polyethylene (HDPE) specimens. The upper stress limit where the specimen ruptured immediately on application of load and the lower stress limit where the specimen sustained the load indefinitely were also features of the model. These two limits were found to depend on the resilience, elastic modulus and anelastic modulus of the HDPE.  相似文献   
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