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51.
Sage (Salvia fruticosa L.), anise (Pimpinella anisum L.), Hawthorn (Crataegus orientalis), rosemary (Rosmarinus officinalis L.), mountain tea (Sideritis spp), basil (Ocimum basilicum L.), lime flower (Tilia cordata), nettle (Urtica dioica L.), thyme (Thymbra spicata), coriander (Coriandrum sativum L.), rosehip (Rosa canina L.), mentha (Mentha piperita L.), balm (Melissa officinalis L.), tea (Camelia sinensis L.) (Black and green), sena leaf (Casia angustifolia), camomile (Matricaria chamomilla), tarragon (Artemisia dracunculus L.), cinnamon (Cinnamomum casia) and fennel (Foeniculum vulgare L.) were used as plant material in this study. Decoction was applied to R. canina, A. dracunculus and C. casia, and infusion was applied to other plant materials. Ten, 15 and 20 min were used as a time parameter for both infusion and decection. Inductive coupled plasma atomic emission spectrometry (ICP-AEs) has been used for the determination of the elements in all infusions, decoctions and plant material.  相似文献   
52.
Alcohols have been used as a fuel for engines since 19th century. Among the various alcohols, ethanol is known as the most suited renewable, bio-based and ecofriendly fuel for spark-ignition (SI) engines. The most attractive properties of ethanol as an SI engine fuel are that it can be produced from renewable energy sources such as sugar, cane, cassava, many types of waste biomass materials, corn and barley. In addition, ethanol has higher evaporation heat, octane number and flammability temperature therefore it has positive influence on engine performance and reduces exhaust emissions. In this study, the effects of unleaded gasoline (E0) and unleaded gasoline–ethanol blends (E50 and E85) on engine performance and pollutant emissions were investigated experimentally in a single cylinder four-stroke spark-ignition engine at two compression ratios (10:1 and 11:1). The engine speed was changed from 1500 to 5000 rpm at wide open throttle (WOT). The results of the engine test showed that ethanol addition to unleaded gasoline increase the engine torque, power and fuel consumption and reduce carbon monoxide (CO), nitrogen oxides (NOx) and hydrocarbon (HC) emissions. It was also found that ethanol–gasoline blends allow increasing compression ratio (CR) without knock occurrence.  相似文献   
53.
Nowadays healthcare organizations globally recognize the importance of investing in information technologies to improve the quality of care delivery and reduce costs. The key drivers of healthcare sector such as continuously improving healthcare standards and insurance systems have introduced new requirements for hospitals, which in return provided a solid ground for decision-makers to consider implementing hospital information systems that are customized and improved versions of enterprise resource planning (ERP) systems designed according to the needs of the healthcare sector. The conventional discounted cash flow methods ignore the value of managerial and strategic flexibility inherent in these investments, which is crucial for justification of the investment decision. This study introduces a real options-based methodology which overcomes the limitations of traditional valuation methods and enables decision-makers to value an ERP system investment incorporating multiple options. The option valuation model developed in this study extends the binomial lattice framework to model a hospital information system (HIS) investment opportunity with compound options. The potential application of the proposed model is illustrated through evaluation of a real-world HIS investment.  相似文献   
54.
In this study, four potential methods are identified for geothermal-based hydrogen production, namely, (i) directly from the geothermal steam, (ii) through conventional water electrolysis using the electricity generated from geothermal power plant, (iii) using both geothermal heat and electricity for high temperature steam electrolysis and/or hybrid processes, (iv) using the heat available from geothermal resource in thermochemical processes to disassociate water into hydrogen and oxygen. Here we focus on relatively low-temperature thermochemical and hybrid cycles, due to their greater application possibility, and examine them as a potential option for hydrogen production using geothermal heat. We also present a brief thermodynamic analysis to assess their performance through energy and exergy efficiencies for comparison purposes. The results show that these cycles have good potential and become attractive due to the overall system efficiencies over 50%. The copper–chlorine cycle is identified as a highly promising cycle for geothermal hydrogen production. Furthermore, three types of industrial electrolysis methods, which are generally considered for hydrogen production currently, are also discussed and compared with the above mentioned cycles.  相似文献   
55.
Intermodal freight transportation is concerned with the shipment of commodities from their origin to destination using combinations of transport modes. Traditional logistics models have concentrated on minimizing transportation costs by appropriately determining the service network and the transportation routing. This paper considers an intermodal transportation problem with an explicit consideration of greenhouse gas emissions and intermodal transfers. A model is described which is in the form of a non-linear integer programming formulation, which is then linearized. A hypothetical but realistic case study of the UK including eleven locations forms the test instances for our investigation, where uni-modal with multi-modal transportation options are compared using a range of fixed costs.  相似文献   
56.
For target tracking applications, wireless sensor nodes provide accurate information since they can be deployed and operated near the phenomenon. These sensing devices have the opportunity of collaboration among themselves to improve the target localization and tracking accuracies. An energy-efficient collaborative target tracking paradigm is developed for wireless sensor networks (WSNs). A mutual-information-based sensor selection (MISS) algorithm is adopted for participation in the fusion process. MISS allows the sensor nodes with the highest mutual information about the target state to transmit data so that the energy consumption is reduced while the desired target position estimation accuracy is met. In addition, a novel approach to energy savings in WSNs is devised in the information-controlled transmission power (ICTP) adjustment, where nodes with more information use higher transmission powers than those that are less informative to share their target state information with the neighboring nodes. Simulations demonstrate the performance gains offered by MISS and ICTP in terms of power consumption and target localization accuracy.  相似文献   
57.
Slurry ice, a biphasic system consisting of small spherical ice crystals surrounded by seawater at subzero temperature, was evaluated as a new chilled storage method for whole sea bass (Dicentrarchus labrax) a sparidae fish species of remarkable commercial interests. In this study two different group of chilling methods were used during transportation; in slurry ice packaged (Group A), and flake ice packaged (Group B). The effect of this advanced system during transportation on quality losses and the shelf life of aquacultured sea bass was evaluated. Mesophilic counts for sea bass exceeded 7 log cfu/g, which is considered the maximum level for acceptability for freshwater and marine fish after 13 days for groups A and B. On day 13 TVB-N values of groups A and B, reached the legal limits (35 mg/100 g set for TVB-N) for consumption. According to the results of sensory analyses, up to day 9 all the groups were determined as "acceptable" but on day 13 the groups A and B were no longer acceptable. The main negative aspect related to quality loss in slurry ice group corresponded to the appearance of eyes and gills. Using slurry ice during transportation did not extend the shelf life of sea bass stored at 4 degrees C.  相似文献   
58.
Xiao  Yunjun  Wei  Jia  Wang  Jiabing  Ma  Qianli  Zhe  Shandian  Tasdizen  Tolga 《Neural computing & applications》2020,32(12):8187-8204
Neural Computing and Applications - Recently, low-rank and sparse representation-based methods have achieved great success in subspace clustering, which aims to cluster data lying in a union of...  相似文献   
59.
3,4-Ethylenedioxythiophene and 3-octylthiophene were electropolymerized on glassy carbon electrodes (GCE) to compare with four different electrolytes [lithium perchlorate (LiClO4), sodium perchlorate, tetraethylammonium tetrafluoroborate, and tetrabutylammonium tetrafluoroborate] in a solvent of acetonitrile (CH3CN). Modified electrodes were characterized by cyclic voltammetry, attenuated total reflectance–Fourier transform IR spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis, atomic force microscopy, and electrochemical impedance spectroscopy (EIS). Nyquist and Bode plots for magnitude, phase, admittance, and capacitance on both polymer-modified electrodes were comparatively investigated in detail. The highest low-frequency capacitance (C LF) and double-layer capacitance (C dl) were obtained in 0.1 M LiClO4/CH3CN for poly(3,4-ethylenedioxythiophene) and poly(octylthiophene)/GCE. EIS data were fitted to the equivalent circuit model of R(Q(R(C(R(C(RW))))))(CR), which is used to investigate circuit parameters.  相似文献   
60.
Geothermal‐based hydrogen production, which basically uses geothermal energy for hydrogen production, appears to be an environmentally conscious and sustainable option for the countries with abundant geothermal energy resources. In this study, four potential methods are identified and proposed for geothermal‐based hydrogen production, namely: (i) direct production of hydrogen from the geothermal steam, (ii) through conventional water electrolysis using the electricity generated through geothermal power plant, (iii) by using both geothermal heat and electricity for high temperature steam electrolysis and/or hybrid processes, and (iv) by using the heat available from geothermal resource in thermochemical processes. Nowadays, most researches are focused on high‐temperature electrolysis and thermochemical processes. Here we essentially discuss some potential low‐temperature thermochemical and hybrid cycles for geothermal‐based hydrogen production, due to their wider practicality, and examine them as a sustainable option for hydrogen production using geothermal heat. We also assess their thermodynamic performance through energy and exergy efficiencies. The results show that these cycles have good potential and attractive overall system efficiencies over 50% based on a complete reaction approach. The copper‐chlorine cycle is identified as a highly promising cycle for geothermal‐hydrogen production. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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