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21.
The conception of net zero energy buildings (NZEB) has been introduced to limit energy consumption and pollution emissions in buildings. Classification of NZEB is based on renewable energy (RE) supply options, energy measurement process, RE-sources location, and balances whether are energetic or exergetic. In general, it is traditionally agreed that there are three main steps to reach the NZEB performance, starting through the use of passive strategies, energy efficient technologies, and then RE generation systems. Then, these three steps could be accompanied with the smart integration of advanced efficient energy technologies. A state of the art shows that the main ZEB studies are related to: energy savings, reduce electric bills, energy independence, pollution reduction, and occupants comfort, in addition, others are more interested in the aesthetic aspect by combining modern technologies with innovations to achieve high energy and sustainability performance. Building optimization is a promising technique to evaluate NZEB design choices; it has been adopted to choose the perfect solution to reach the zero energy performance through the optimization of an objective function related to energy (thermal loads, RE generation, energy savings) and/or environment (CO2 emissions) and/or economy (life-cycle cost (LCC), net-present value (NPV), investment cost). This paper starts by presenting the global energetic and pollution challenges the world faces. Moreover, it shows, to the best to the author’s knowledge, the existing NZEB definitions and the corresponding case studies investigated in 8 different climatic zones (humid continental, humid subtropical, Mediterranean, moderate continental, moderate continental, marine west coast, tropical, semi-arid and hot), the paper also focus on the importance to treat each climate separately. Even in the same country, two or more climates may co-exist. NZEBs drawbacks are also presented. Furthermore, different optimization problems are reviewed in the last section. Building energy optimization methods are employed to obtain the ideal solution for specific objective functions which are either related to energy, and/or environment and/or economy. Optimization variables are distributed between passive and/or RE generation systems. Finally, a table summarizing the most commonly used electric and thermal RE applications which yield to the zero energy balance in each climate, as well as three flowcharts are presented to summarize the whole three-stage procedure, to reach NZEB, starting from building designing, passing through the optimization procedure, and lastly categorizing the zero energy balance. 相似文献
22.
The effect of animal diet (pasture versus grain) and fat content (1, 15 and 25%) on the functional properties and quality of beef stored for 8 months at −20 °C was determined. After storage, pasture-finished beef had significantly (P<0.001) less malondialdehyde than grain-finished. Grain-finished beef had a more vivid red colour than pasture-finished (P<0.01). The remaining functional properties determined in this study were not affected by diet. Protein solubility, emulsion activity index, and cooked batter torsion strain decreased and hue angle increased with increasing fat content. The solubility of total and sarcoplasmic proteins and cooked batter torsion stress and strain decreased (P<0.001) and hue angle increased (P<0.001) with storage time regardless of diet and fat content. It is concluded that there is not much difference in the functional properties of beef finished on pasture or grain. However, pasture-finished beef is more stable to lipid oxidation than the grain-finished, and hence may be more amenable to further processing. 相似文献
23.
The effects of rigor temperature and electrical stimulation on venison quality were assessed using venison longissimus dorsi muscle. In the first trial, effect of rigor temperature (0, 15, 25, 30, 35 and 42 °C) and time post-mortem (at rigor, 3, 7 and 14 days) on drip and cooking losses, % expressible water (water holding capacity, WHC), sarcomere length, protein solubility, meat tenderness and colour were investigated. In the second trial, the effects of rigor temperature (15 and 35 °C), electric stimulation (stimulated or not stimulated) and time (at rigor, 3 and 6 weeks post-mortem) on tenderness and colour were further investigated. Results of the first trial showed no clearly established trends of the effect of rigor temperature and time on the cooking and drip losses and protein solubility except venison muscles that went into rigor at 42 °C tended to have higher drip loss and lower protein solubilities compared to muscles that went into rigor at the other temperatures. Venison water holding capacity (WHC) decreased with the increase in rigor temperature (P < 0.001) and venison became more tender with time post-mortem. Venison colour improved with increasing rigor temperature. During display, samples that went into rigor at 15, 25 and 35 °C had the lowest and those at 0 and 42 °C had the highest rate of change of redness (a*) value with time. In the second trial, tenderness was improved by stimulation (P = 0.01). Redness (a*) values were affected by rigor temperature (P < 0.01) and post-mortem time (P < 0.001) but not by electrical stimulation. It is concluded that venison tenderness can be improved via the manipulation of rigor temperature to obtain acceptable level of tenderness early post-mortem with less damaging effect on colour stability. 相似文献
24.
Ahmed Chabane Fatiha Bouchal Mohamed Hentabli Nabila Ayachi Houssam Eddine Slama Farouk Rezgui Lydia Hammoumraoui 《加拿大化工杂志》2023,101(8):4446-4459
Candesartan is an angiotensin receptor blocker (ARB) used to treat hypertension. However, its poor aqueous solubility and oral bioavailability have limited its therapeutic applications. In order to increase bioavailability and control the release of candesartan condensation, microspheres containing biodegradable polymers (polyvinylpyrrolidone [PVP K30] and polylactic acid [PLA]) in different ratios were prepared by the o/o solvent evaporation method using Span 80 as a surfactant. In addition, the impact of encapsulation parameters (i.e., PVP K30 and PLA concentrations) on the encapsulation ratio and release percentage was investigated by the mixed factorial design method. The release kinetics of the microspheres was simulated by combining two methods, the Dragonfly algorithm and a support vector machine (DA-SVM). The experimental data were in good agreement with the predicted data, with a coefficient of determination close to unity and a mean square error close to zero. Fourier-transfer infrared spectrometry (FTIR) analysis revealed the presence of condensation in all formulations without reporting distortion in the spectra. Scanning electron microscopy (SEM) confirmed the successful synthesis of microspheres, whose sizes were between 12 and 26 μm. Formulations with a PLA-drug ratio of 6:1 (N15, N17, and N18) showed the highest encapsulation efficiency (68%, 71%, and 70%, respectively), while formulations that do contain PVP K30, such as N5, N4, and N3, showed a higher release (83%, 84%, and 89%, respectively), indicating that the agent (PVP K30) enhanced the bioavailability and release of candesartan. Overall, N3 showed a higher drug release rate at 12 h and important encapsulation efficiency, making it the optimal formulation obtained in this study. 相似文献
25.
Farouk Belkadi Nicolas Dremont Alban Notin Nadege Troussier Mourad Messadia 《Annual Reviews in Control》2012,36(2):346-358
The design of complex system requires a lot of interactions between experts and then between numerous Computer Aided X software (CAX) (where X can be Design (CAD), Engineering (CAE), Manufacturing (CAM), etc.). In order to improve the consistency of the whole system design and the related data and information, knowledge crossing the expertises must be tracked and formalized regarding a shared reference. That means that instead of defining a large reference models to which each expert refers to, a light collaborative model is defined enabling to connect data from each expert model to adhoc data from other expert models, following the least commitment principle. In this topic, a new meta-model is proposed in a Model-Driven Engineering approach to manage the integration of heterogeneous experts’ knowledge models in a collaborative process. The structure of the proposed knowledge meta-model is defined taking into account the complexity of knowledge definition and the properties of its components. This meta-model is split in a meta-model of data on one hand and a Collaboration Meta-Model in the other hand, to represent the distinction between the core concepts of knowledge and additional elements serving to represent the relation between these concepts, and between concepts of heterogeneous experts’ models. The proposed meta-model is illustrated on an industrial case study to highlight the way to put it in use, and its interests to enable collaboration between experts throughout the design process. 相似文献
26.
Mokhtar Adel Boukoussa Bouhadjar Baba Ahmed Abderrazzak Abdelkrim Soumia Djelad Amal Hachemaoui Mohammed Zaoui Farouk Bengueddach Abdelkader Sassi Mohamed 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(7):2615-2633
Journal of Inorganic and Organometallic Polymers and Materials - The discharge of industrial waste comprising organic pollutants into aquatic environment induces numerous health risks. Crosslinked... 相似文献
27.
M Filippi TA Yousry MA Rocca C Pereira H Alkadhi G Comi 《Canadian Metallurgical Quarterly》1998,4(6):471-474
A case of ovarian mixed germ cell tumor in a 44-year-old woman was examined. The tumor was well circumscribed, measured 15 x 11 x 10 cm and appeared solid and partly cystic on the cut surface. Light microscopic examinations revealed that the tumor was composed of four different neoplastic germ cell elements, intermingled with each other. They are: (i) choriocarcinoma, immunohistochemically positive for human placental lactogen (hPL) and human chorionic gonadotropin (hCG); (ii) dysgerminoma, positive for placental alkaline phosphatase; (iii) endodermal sinus tumor positive for alpha-fetoprotein (AFP); and (iv) mature teratoma. Among these histological types, dysgerminoma occupied more than 50% of the neoplasm. The patient was diagnosed as a stage la ovarian mixed germ cell tumor and was subsequently treated with chemotherapy. A second-look laparotomy after completion of chemotherapy revealed no residual tumors in the abdomen and the patient is alive and well 15 months after operation. This is the fourth reported case of ovarian mixed germ cell tumor arising in patients over 40 years old. 相似文献
28.
Fathi Habashi Farouk T. Awadalla 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1986,36(1):1-6
When phosphate rock is dissolved in nitric acid, phosphoric acid and uranium can be selectively extracted by tertiary amyl alcohol; other impurities including the lanthanides remain in the aqueous phase. Uranium can be recovered from the alcohol phase by selective stripping and the lanthanides from the raffinate by extraction with tributyl phosphate. 相似文献
29.
DWT-based joint antenna selection for correlated MIMO channels 总被引:1,自引:0,他引:1
Ehab Farouk Badran 《Signal, Image and Video Processing》2009,3(1):35-45
This paper proposes a new discrete wavelet transform (DWT)-based joint antenna selection scheme for spatially correlated multiple-input
multiple output (MIMO) channels. To reduce the severe performance degradation of the traditional antenna selection schemes
in correlated channels, a new scheme which employ joint antenna selection (JAS) at both link ends algorithm and embed DWT
operations in the receiver-end RF chains is proposed. Through extensive simulations it is demonstrated that the proposed DWT-based
joint antenna selection has significant improvement of the capacity for both i.i.d and correlated MIMO channels, while requiring
only a minor hardware overhead and low computational complexity for the DWT operations. Moreover, it is shown that the capacity
associated with DWT-based JAS is higher than the system employing DWT-based receive antenna selection (RAS) only. This is
achieved in i.i.d. and correlated MIMO channels. 相似文献
30.
The present study describes the effects of glycerol, relative humidity (RH) and the minor components of corn flour on mechanical and thermal properties of native flour, defatted flour, and starch‐based materials. The kinetic of retrogradation for these different materials were dissimilar. For all samples, strain at break shows a maximum value as a function of RH followed by a decrease, explained by the appearance of water and glycerol clusters. Starch controls the mechanical properties of corn flour‐based material and their variations with temperature and humidity. Lipid and protein have negative effect on mechanical properties of thermoplastic flour toward starch but they did not have a plasticizing effect on the physicochemical behavior of the matrix. Tgs decreased as a result of water content increase. 相似文献