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951.
Volatile composition of pomegranates from 9 Spanish cultivars using headspace solid phase microextraction 总被引:3,自引:0,他引:3
Melgarejo P Calín-Sánchez Á Vázquez-Araújo L Hernández F Martínez JJ Legua P Carbonell-Barrachina ÁA 《Journal of food science》2011,76(1):S114-S120
Fruits of 9 Spanish pomegranate cultivars were analyzed for quality parameters, volatile composition, and sensory profile. Volatile compounds were extracted using headspace solid phase micro-extraction (HS-SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS) and flame ionization detector (GC-FID). Twenty-one compounds were found in the headspace of fresh pomegranate juices, including aldehydes, monoterpenes, and alcohols. The most abundant compounds were hexanal, limonene, trans-2-hexenal, and cis-3-hexenol. Fruits from the cultivars Mollar Elche(ME) ME14, ME1, and ME2 presented the highest values of overall liking by the consumer panel; however, their total volatiles concentration were low compared to the other pomegranate cultivars and their color intensity was intermediate. Overall consumer liking of pomegranate juices was mainly associated with the presence of monoterpenes (α-terpineol); however, high aldehydes (trans-2-hexenal) concentrations were correlated with poor overall consumer liking. Fruits from sour-sweet cultivars (PTO7 and ADO4) could improve the quality of ME pomegranate juices due to their intense color, high monoterpenes concentrations, and their moderate sourness. Practical Application: The information provided in this study proves that sour-sweet pomegranate fruits can be used in the manufacturing of pomegranate juices and will improve the sensory quality and the volatile composition of this product. 相似文献
952.
Pasini F Verardo V Cerretani L Caboni MF D'Antuono LF 《Journal of the science of food and agriculture》2011,91(15):2858-2864
BACKGROUND: Salad crops of the Brassicaceae family, such as Diplotaxis tenuifolia and Eruca vesicaria, commonly referred to as ‘rocket salads’, have attracted considerable interest as culinary vegetables because of their strong flavour and their content of putative health‐promoting compounds. Among such compounds, glucosinolates and phenolics are well‐known phytochemicals with an important role also in determining the characteristic flavour of these species. In this study, to identify potentially high‐value rocket salads, 37 cultivated types were examined for sensory characters and their relations with glucosinolate and phenolic contents, which ranged from 0.76 to 3.03 g kg?1 dry weight (DW) and from 4.68 to 31.39 g kg?1 DW, respectively. RESULTS: The perception of bitter taste was significantly affected by specific glucosinolates, namely progoitrin/epiprogoitrin and dimeric glucosativin. Aroma intensity was negatively related to glucoalyssin content, whereas pungency was significantly related to total glucosinolate content. Kaempferol‐3‐(2‐sinapoyl‐glucoside)‐4′‐glucoside was positively and significantly related to all flavour trait perceptions. Aroma intensity, pungency, crunchiness and juiciness were positively related to typical rocket salad flavour perception through a prominent direct effect. CONCLUSION: Aroma intensity, pungency, crunchiness and juiciness were strong determinants of overall rocket salad flavour perception. Visual traits also characterised sensory components. Bitterness, usually considered a negative flavour trait, was moderately perceived in the examined material, without negatively affecting typical flavour perception. In the range of the examined material, glucosinolate content did not contrast with typical flavour, demonstrating that good taste and putative health‐promoting properties may coexist. Copyright © 2011 Society of Chemical Industry 相似文献
953.
Monitoring the sensorial quality and aroma through an electronic nose in peaches during cold storage
Rodrigo Infante Macarena Farcuh Claudio Meneses 《Journal of the science of food and agriculture》2008,88(12):2073-2078
BACKGROUND: The poor eating quality of fresh peaches transported to far markets is one of the main problems that fresh‐fruit exporting countries have to face. This research is focused on the evaluation of the sensorial quality, with emphasis on aroma, of four peach cultivars kept in long‐term storage, through maturity parameters, sensorial attributes and electronic nose (e‐nose) assessments. Fruits were stored at 0 °C and 90% elative humidity, for 14, 28 and 42 days. Evaluations were carried out after the fruit was taken out of cold storage and after a variable period of ripening at 21 °C, until flesh firmness reached 1–2 kgf. RESULTS: On fruit recently harvested, the e‐nose was suitable for discriminating among cultivars, even if it corresponded to an early pre‐climacteric phase. As cold storage proceeded, liking degree, and specially aroma, declined for each cultivar tested. Cultivars showed different behavior patterns for liking degree and especially aroma during cold storage. Flavor showed significant correlation with sweetness (r = 0.92), juiciness (r = 0.92) and texture (r = 0.93), but not with aroma and acidity, being these last ones being independent from each other. CONCLUSION: Post‐harvest storage life of peaches is limited by loss of quality. ‘Tardibelle’ peaches showed the highest quality attribute scores after 42 days of cold storage. This evidences the availability of commercial peach cultivars which are able to withstand long‐term storage periods, allowing far markets to be reached with high quality standards. Copyright © 2008 Society of Chemical Industry 相似文献
954.
Prediction and measurement of pasta quality 总被引:1,自引:0,他引:1
M. E. COLE 《International Journal of Food Science & Technology》1991,26(2):133-151
In the past several years, pasta and noodle products have become a major growth segment of the cereal foods industry. The popularity of pasta can be attributed to its sensory appeal, versatility, low cost, ease of preparation, strong nutritional image and excellent storage stability as well as to increased consumer interest in ethnic foods. Predominant quality attributes of pasta, as they relate to its appearance, flavour and texture, have been described in this review. Because of their importance to consumer acceptance, textural properties of pasta and noodles have been investigated most extensively. Commonly applied sensory, instrumental and chemical methodologies for prediction or measurement of these characteristics have been critiqued, and pitfalls of current approaches have been delineated. Although sensory appraisal has often been used to evaluate pasta quality, increasing reliance on physical and chemical measurements to provide estimates of product quality has been occurring recently in research laboratories. 相似文献
955.
The challenge of Intelligent Manufacturing Systems (IMS): the European IMS information event 总被引:1,自引:0,他引:1
Peter P. Groumpos 《Journal of Intelligent Manufacturing》1995,6(1):67-77
In the suburb of Patras, Rion on 7–8 April, the European Intelligent Manufacturing Systems (IMS) Information Event took place, in the form of a symposium. The symposium was organized, as part of the IMS series of dissemination events, by the EC after the completion of the two-year feasibility study. The main objective of the event was the presentation of the results of each test case and of the feasibility study in general. Interactive sessions were organized to discuss the experience of international cooperation. The symposium was coorganized with the University of Patras. 相似文献
956.
为开发肩关节在原点且手部做三维运动的智能型关节式机器人实时控制系统 ,本文提出了用一个单位矢量有向角取代用三个单位矢量方向余弦描述手部姿态的新概念 ,提出了由关节变量确定位姿及由位姿确定各组关节变量的简单算法 ,探讨了手部姿态固定时的 16组关节变量 ,并通过实例说明了该方法。 相似文献
957.
本文介绍了银行智能大楼接地及防雷设计思路 ,并结合具体工程实例对雷电浪涌防护进行了总结 相似文献
958.
A parallel processing architecture for sensor-based control of intelligent mobile robots 总被引:6,自引:0,他引:6
Parallel processing plays an important role in sensor-based control of intelligent mobile robots. This paper describes the design and implementation of a parallel processing architecture used for real-time, sensor-based control of mobile robots. This architecture takes the form of a network of sensing and control nodes, based on a novel module that we call Locally Intelligent Control Agent (LICA). It is a hybrid control architecture containing low-level feedback control loops and high-level decision making components. All the sensing, planning, and control tasks for intelligent control of a mobile robot are distributed across such a network, and operate in parallel. It has been used successfully in many experiments to perform planning and navigation tasks in real-time. Such a generic architecture can be readily applied to many diverse applications. 相似文献
959.
Management of complexity, changes and disturbances is one of the key issues of production today. Distributed, agent-based structures represent viable alternatives to hierarchical systems provided with reactive/proactive capabilities. In the paper, approaches to distributed manufacturing architectures are surveyed, and their fundamental features are highlighted, together with the main questions to be answered while designing new structures. Moreover, an object-oriented simulation framework for development and evaluation of multi-agent manufacturing architectures is introduced. 相似文献
960.
根据循环流化床锅炉床温对象的动态特性,提出了一种自整定智能控制器.该控制器从
对人宏观结构模拟和行为功能模拟的观点出发,通过特征辨识、直觉推理给出了多模态控制策
略.将该控制器应用于国产75t/h循环流化床锅炉床温系统获得满意效果. 相似文献