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971.
The chemical industry is one of the key industrial sectors in Germany and at the same time one of the largest consumers of energy and raw materials. A successful energy transition and the development of a circular economy can only succeed if they are actively supported and shaped by the chemical industry – through the redesign of existing production processes and the exploration and implementation of new process routes. The challenge is to realize this transformation within a very short time and for many production processes, whereby a much larger number of process routes must be explored. Digital technologies are key to master this transformation towards more sustainability, climate, and environmental protection. The KEEN project aims to explore and leverage artificial intelligence (AI) opportunities in process industry. The newly developed AI methods are tested wherever possible in real working environments and production plants to prove the economic benefit, applicability, and reliability of the methods and technologies.  相似文献   
972.
973.
Clean Technologies and Environmental Policy - Objective is to analyze the economic feasibility of implementing a greenhouse in a hydroponics production system in substrate (sand) on a small family...  相似文献   
974.
Bacterial biofilm formation in low moisture food processing (LMF) plants is related to matters of food safety, production efficiency, economic loss, and reduced consumer trust. Dry surfaces may appear dry to the naked eye, however, it is common to find a coverage of thin liquid films and microdroplets, known as microscopic surface wetness (MSW). The MSW may favor dry surface biofilm (DSB) formation. DSB formation is similar in other industries, it occurs through the processes of adhesion, production of extracellular polymeric substances, development of microcolonies and maturation, it is mediated by a quorum sensing (QS) system and is followed by dispersal, leading to disaggregation. Species that survive on dry surfaces develop tolerance to different stresses. DSB are recalcitrant and contribute to higher resistance to sanitation, becoming potential sources of contamination, related to the spoilage of processed products and foodborne disease outbreaks. In LMF industries, sanitization is performed using physical methods without the presence of water. Although alternative dry sanitizing methods can be efficiently used, additional studies are still required to develop and assess the effect of emerging technologies, and to propose possible combinations with traditional methods to enhance their effects on the sanitization process. Overall, more information about the different technologies can help to find the most appropriate method/s, contributing to the development of new sanitization protocols. Thus, this review aimed to identify the main characteristics and challenges of biofilm management in low moisture food industries, and summarizes the mechanisms of action of different dry sanitizing methods (alcohol, hot air, UV-C light, pulsed light, gaseous ozone, and cold plasma) and their effects on microbial metabolism.  相似文献   
975.
Single atoms and nanoclusters of Fe, Ni, Co, Cu, and Mn are systematically designed and embedded in a well-defined C1N1-type material that has internal cavities of ≈0.6 nm based on four N atoms. These N atoms serve as perfect anchoring points for the nucleation of small nanoclusters of different metal natures through the creation of metal-nitrogen (TM-N4) bonds. After pyrolysis at 800 °C, TM@CNx-type structures are obtained, where TM is the transition metal and x < 1. Fe@CNx and Co@CNx are the most promising for oxygen reduction reaction and hydrogen evolution reaction, respectively, with a Pt-like performance, and Ni@CNx is the most active for oxygen evolution reaction (OER) with an EOER of 1.59 V versus RHE, far outperforming the commercial IrO2 (EOER = 1.72 V). This systematic and benchmarking study can serve as a basis for the future design of advanced multi-functional electrocatalysts by modulating and combining the metallic nature of nanoclusters and single atoms.  相似文献   
976.
This study aimed to evaluate the effect of high-intensity ultrasound (HIUS) application with different processing times (2.5, 5, 7.5 and 10 min) on the physicochemical, rheological and textural properties, antioxidant activity (AA) and probiotic survival in strawberry-flavoured fermented probiotic strawberry drink during storage (7°C for 28 days). The application of HIUS resulted in products with lower fermentation times, higher organic acid stability during storage and improved texture (higher firmness and consistency) and functional properties (higher phenolic compounds content and/or AA). Using 2.5 min of processing time would be advisable due to the better probiotic survival to simulated gastrointestinal conditions (probiotic counts higher than 106 CFU mL−1), reduced fermentation times (reduction in 3 h), higher lactic acid content during storage and enhanced AA. The products showed a viable probiotic counts higher than 106 CFU mL−1 during the entire shelf life. HIUS may be considered as an adequate pre-treatment in the development of probiotic fermented probiotic strawberry drink.  相似文献   
977.
The effect of different cocoa composition of dark chocolate samples and their ingredients on their thermal, structural and rheological characteristics was investigated. Thermal behavior was evaluated by means of differential scanning calorimetry (DSC), while the crystal morphology was observed by polarized light optical microscopy. The rheological measurements were carried out using both continuous and oscillatory experiments. The formation of more stable polymorphic structures was time and temperature dependent; and it was not affected by either cocoa composition or particle sizes. The kinetics of crystallization was determined by a step crystallization method and modeled by the Avrami equation, it was accelerated by solid particles concentration, lower particle size and lower crystallization temperatures. Negative spherulites with featherlike microstructures defined the time dependent crystal growth and were consistent with Avrami indexes of 3–4. Under continuous shear, cocoa butter was well described by the Bingham rheological model, while Casson and Carreau equations modeled the flow of cocoa liquor and chocolate samples. However the Carreau model was preferred for presenting better fittings and for predicting apparent viscosities at low and at high shear rates. From both, continuous and oscillatory experiments, it was found that composition of chocolate samples in terms of fat and nonfat cocoa solids, and sugar content, affected their rheological behavior. The solid liquid transition of chocolate samples and cocoa liquor was obtained at a yield stress of around 1 Pa from both continuous and oscillatory shear experiments.  相似文献   
978.
316L and Cu-based inks are developed to 3D-printed tetrachiral auxetic structures. The main objectives of the work are to study the effects of powders composition and powder:binder volume ratio on rheological properties and printability of the inks. Following these results, customized Gcode is developed using FullControl Gcode Designer open-source software to 3D print intricate tetrachiral auxetic structures. The results reported in this work show how powder composition (316L versus Cu) has less effect on the inks’ rheological behavior than powder size distribution and powders:binder volume ratio. In terms of rheological parameters, the zero-shear rate viscosity mainly affects the capability of the printed ink to retain its shape after printing, while the yield stress affects the printability. The printed and sintered auxetic structures achieve the intended lattice-geometry design.  相似文献   
979.
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