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131.
132.
Pure poly(dimethylsiloxane) (PDMS) films, PDMS-nanodiamond (ND) and pure nanodiamond powder were irradiated with 2?MeV protons under a variety of fluence and current conditions. Upon proton irradiation, these samples acquire a fluence-dependent photoluminescence (PL). The emission and excitation spectra, photostability and emission lifetime of the induced photoluminescence of PDMS and PDMS-ND samples are reported. Pure PDMS exhibits a noticeable stable blue PL, while the PDMS-ND composites exhibit a pronounced stable green PL under 425?nm excitation. The PL of PDMS-ND composites is much more prominent than that of pure PDMS or pure ND powder even when irradiated at higher doses. The origin of the significantly enhanced PL intensity for the proton-irradiated PDMS-ND composite is explained by the combination of enhanced intrinsic PL within ND particles due to ion-implantation-generated defects and by PL originating from structural transformations produced by protons at the nanodiamond/matrix interface.  相似文献   
133.
Assistive Device Art derives from the integration of Assistive Technology and Art, involving the mediation of sensorimotor functions and perception from both, psychophysical methods and conceptual mechanics of sensory embodiment. This paper describes the concept of ADA and its origins by observing the phenomena that surround the aesthetics of prosthesis-related art. It also analyzes one case study, the Echolocation Headphones, relating its provenience and performance to this new conceptual and psychophysical approach of tool design. This ADA tool is designed to aid human echolocation. They facilitate the experience of sonic vision, as a way of reflecting and learning about the construct of our spatial perception. Echolocation Headphones are a pair of opaque goggles which disable the participant’s vision. This device emits a focused sound beam which activates the space with directional acoustic reflection, giving the user the ability to navigate and perceive space through audition. The directional properties of parametric sound provide the participant a focal echo, similar to the focal point of vision. This study analyzes the effectiveness of this wearable sensory extension for aiding auditory spatial location in three experiments; optimal sound type and distance for object location, perceptual resolution by just noticeable difference, and goal-directed spatial navigation for open pathway detection, all conducted at the Virtual Reality Lab of the University of Tsukuba, Japan. The Echolocation Headphones have been designed for a diverse participant base. They have both the potential to aid auditory spatial perception for the visually impaired and to train sighted individuals in gaining human echolocation abilities. Furthermore, this Assistive Device artwork instigates participants to contemplate on the plasticity of their sensorimotor architecture.  相似文献   
134.
With the closing of the age-related gap in mobile phone uptake and the aging of the population, older adults have increasingly become a desirable target group for mobile phone providers. Although there is abundant literature describing the use of mobile phones among older adults, segmentation studies on this group of consumers remain scant and inconclusive. Drawing on the benefit and behavioral segmentation, this study presents a segmentation model of older adults in the mobile phone market that incorporates a wide variety of consumer behavior, attitudinal, and acceptance variables relevant for the understanding of mobile phone (non-)usage patterns among users of feature phones and smartphones, as well as among mobile phone nonusers. The model is based on a hybrid approach with a two-step cluster analysis using data collected by a telephone survey from a representative sample (n = 1,581) of adults aged 55 or older in Slovenia in 2015. The analysis yielded two uniquely profiled clusters within each of the five a priori-determined segments, summing to a total of 10 clusters. The results show that older adults still prefer feature phones. Nevertheless, the mobile phone market has become highly heterogeneous, with clusters of older adults having distinguishable feature phone- and smartphone-use patterns as well as socio-demographic and life-course profiles. Since many of these profiles undermine the notion of older adults as “basic” mobile phone users, our findings represent a solid foundation for scholars and marketers to further investigate their specific needs in relation to more advanced smartphone and mobile internet usage.  相似文献   
135.
In the present study the SHETRAN river basin modelling system was used in conjunction with Geographic Information System (GIS) to estimate potential erosion and deposition rates within the catchment and the concentrations of sediment in a flow at the catchment outlet on the example of the 114.31 km2 mountainous torrential Lukovska River catchment in Serbia. The streams in the Lukovska River catchment are short, steep and often produce hazardous torrential floods as a consequence of strong rainfall of short duration. The soil erosion and sediment discharge were analysed in view of the catchment response to physical characteristics of the catchment. Considering that the most of total annual sediment discharge in watersheds of torrential character is achieved during storm events, the SHETRAN modelling system was calibrated on the example of a storm event in 1986 and validated for three other storm events in 1974, 1976 and 1979. The simulated results of discharges and sediment concentrations at the catchment outlet for both calibration and validation events were compared with the observed data and found to be reasonable. The changes of erosion and deposition rates within the catchment and in the course of time were estimated for the calibration event in 1986. The simulated erosion rates were within the range of 1 to 10.5 t/ha and corresponded to the observed rates of erosion in Europe during extreme rain events. The presented methodology is useful in identifying the erosion vulnerable regions in a catchment where erosion control measures should be implemented.  相似文献   
136.
The Croatian Chemical Society was established in 1926 and has developed over the decades into a society that actively supports all chemical activities in Croatia. The Society has eight divisions, the youngest of which, the Division of Medicinal and Pharmaceutical Chemistry, was established in 2012 and immediately became a member of the European Federation of Medicinal Chemistry (EFMC). The mission of the Medicinal and Pharmaceutical Chemistry Division is the promotion and development of scientific, professional, and educational activities within the medicinal chemistry community in Croatia, as well as to build partnerships and collaborations with other primarily EU‐based medicinal chemistry societies. In Croatia, medicinal chemistry research is ongoing at several institutes, including the University of Zagreb (Faculty of Science, Faculty of Pharmacy and Biochemistry, and Faculty of Chemical Engineering and Technology), national institutes of science (Ru?er Bo?kovi? Institute), and private‐sector drug discovery companies (CRO Fidelta Ltd.). In order to effectively exchange knowledge, ideas, and scientific results, Croatian medicinal chemists meet twice annually.  相似文献   
137.
Machine learning models in metabolomics, despite their great prediction accuracy, are still not widely adopted owing to the lack of an efficient explanation for their predictions. In this study, we propose the use of the general explanation method to explain the predictions of a machine learning model to gain detailed insight into metabolic differences between biological systems. The method was tested on a dataset of 1H NMR spectra acquired on normal lung and mesothelial cell lines and their tumor counterparts. Initially, the random forests and artificial neural network models were applied to the dataset, and excellent prediction accuracy was achieved. The predictions of the models were explained with the general explanation method, which enabled identification of discriminating metabolic concentration differences between individual cell lines and enabled the construction of their specific metabolic concentration profiles. This intuitive and robust method holds great promise for in‐depth understanding of the mechanisms that underline phenotypes as well as for biomarker discovery in complex diseases.  相似文献   
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139.
Aluminum was incorporated into a polycrystalline cadmium electrode surface by underpotential deposition from equimolar AlCl3+ NaCl melt at 473 K, 523 K, and 573 K (200 °C, 250 °C, and 300 °C). The process was studied by linear sweep voltammetry and potentiostatic deposition/galvanostatic striping. The deposits were characterized X-ray diffraction (XRD), Auger electron spectroscopy (AES), and electron probe microanalyzer (EPMA). The electrochemical measurements showed evidence of Cd-Al alloys being formed but they could not be identified. The growth kinetics of the Cd-Al layers of various proportion and depths that depended on temperature and deposition time were described.  相似文献   
140.
Buildings could play a critical role in energy and food production while making high-density cities more resilient. Productive façades (PFs), as flexible and multi-functional systems integrating photovoltaic (PV) and vertical farming (VF) systems, could contribute to transforming buildings and communities from consumers to producers. This study analyses the architectural quality of the developed PF concept drawing on the findings of a web-survey conducted among experts – building professionals in Singapore. The developed design variants are compared with regards to key design aspects such as façade aesthetics, view from the inside, materialisation, ease of operation, functionality and overall architectural quality. The study also compares and discusses the results of the web-survey with the results of a previously conducted door-to-door survey among the potential users – residents of the Housing &; Development Board (HDB) blocks. The findings confirm an overall acceptance of the PF concept and reveal a need for synergetic collaboration between architects/designers and other building professionals. Based on the defined PF design framework and the results of the two surveys, a series of recommendations and improved PF prototypes are proposed for further assessment and implementation in order to foster their scalability from buildings into communities and cities.  相似文献   
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