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101.
This paper proposes a design methodology for very small databases for the purpose of being hosted by portable devices. Three main differences w.r.t. the traditional design methodologies are introduced: first, the main mobility issues are considered along with data distribution; second, context awareness is included in the data design issues to allow full exploitation of context-sensitive application functionalities; and third, the peculiarities of the storage device (s) are taken into account by introducing a logistic phase after the usual conceptual and logical phases. The three aspects together determine the VSDB ambient which is the set of personal and environmental characteristics determining the portion of data that must be stored on the portable device. This paper details the design methodology in its conceptual, logical and logistic phases. 相似文献
102.
Graeme Ritchie 《Minds and Machines》2007,17(1):67-99
Over recent decades there has been a growing interest in the question of whether computer programs are capable of genuinely
creative activity. Although this notion can be explored as a purely philosophical debate, an alternative perspective is to
consider what aspects of the behaviour of a program might be noted or measured in order to arrive at an empirically supported
judgement that creativity has occurred. We sketch out, in general abstract terms, what goes on when a potentially creative
program is constructed and run, and list some of the relationships (for example, between input and output) which might contribute
to a decision about creativity. Specifically, we list a number of criteria which might indicate interesting properties of
a program’s behaviour, from the perspective of possible creativity. We go on to review some ways in which these criteria have
been applied to actual implementations, and some possible improvements to this way of assessing creativity.
相似文献
Graeme RitchieEmail: |
103.
104.
关于计算机科学与技术认知问题的研究简报(Ⅰ,Ⅱ) 总被引:24,自引:1,他引:23
赵致琢 《计算机研究与发展》2001,38(1):1-15
计算机科学与技术的认知对学科的科学研究与人才培养具有重要的意义,对计算机科学与技术学科发展的主线、特点和内在规律进行了回顾与总结,从科学哲学的角度阐述了学科的一系列认知问题,并概要介绍了学科方法论研究的主要进展,讨论了学科方法论研究进展对学科未来发展和人才培养可能产生的影响。 相似文献
105.
A Review of Approaches to Developing Service Management Systems 总被引:3,自引:0,他引:3
David Lewis 《Journal of Network and Systems Management》2000,8(2):141-156
As service management systems are deployed in an open service market environment, the pressures on their developers to shorten development times and improve the flexibility of systems will increase. Component reuse may help in alleviating some of these pressures; however, while object-oriented reuse is used in the definition of interfaces for management systems, the systematic application of reuse to the systems' internal design is not well established. This paper examines some of the approaches applicable to service management system development from the Telecommunications, Distributed Systems, Internet and Software Engineering fields. Experience in applying some of these approaches is presented, and based on this, refined approaches to service management system development are discussed. 相似文献
106.
A rapid screening system for heterogeneous catalyst discovery has been developed by coupling an in-house designed and fabricated high temperature vapor phase pulse reactor on-line to a GC-MS. The incorporation of gas chromatography for separation of the products with the mass spectrometry system allowed simultaneous identification and determination of reaction products and substrate conversion. This system was employed to study the vapor phase catalytic hydride transfer reduction (CHTR) of nitrobenzene with methanol as hydrogen donor on an MgO catalyst as a model reaction. Structural information of all the by-products that were formed was useful to understand the reaction mechanism. The products obtained with the new screening technique were in good agreement with conventional bench scale experiments. The rapid online screening provided an efficient methodology for optimization of reaction conditions such as catalyst loading, reaction temperature, and mole ratios. Response Surface Methodology (RSM) was used to optimize the conversion of reactants and selectivity of products. 相似文献
107.
碱性蛋白酶水解豌豆蛋白及其产物抗氧化活性研究 总被引:1,自引:0,他引:1
采用碱性蛋白酶(Alcalase)水解豌豆蛋白,对不同条件下制备的豌豆蛋白酶水解产物DPPH·清除率进行了研究,在单因素试验基础上采用响应面分析方法优化酶水解条件,得到最佳酶解工艺条件为:酶解温度56.5℃,酶解时间3.2 h,pH6.1,加酶量3.0%,底物浓度3.0%,在此条件下,碱性蛋白酶水解产物对DPPH·的清除率为47.83%. 相似文献
108.
响应面法优化芽孢杆菌LJ-7发酵产酯酶条件 总被引:1,自引:1,他引:0
为了获得海洋芽孢杆菌LJ-7发酵产酯酶的最佳条件,采用响应面法对其发酵条件进行了优化。首先,通过单因素试验选出对酯酶产量影响较显著的3个因素,即发酵温度、初始pH和发酵时间。在单因素试验的基础上,采用Box-Benhnken中心组合方法进行三因素三水平的试验设计,以酶活为响应值,利用响应面分析法进行进一步优化,确定最佳发酵条件为:发酵时间42.81h,发酵温度29.40℃,pH为6.21,此时预测的酯酶酶活为24.91 U/mL。在此最佳条件下,平行试验测得实际酶活为24.63U/mL,达到理论预测值的95%以上。该模型较好地预测了实际发酵情况,得到的优化条件具有实际应用价值。 相似文献
109.
高产S-腺苷蛋氨酸的酿酒酵母发酵条件的响应面法优化 总被引:1,自引:1,他引:0
利用Design Expert软件,采用Plackett-Burman(PB)设计和响应面法(RSM)对产S-腺苷蛋氨酸(SAM)的酵母菌株的发酵条件进行优化,PB实验设计及分析结果表明,接种量、L-Met质量浓度、发酵时间是影响SAM胞内产量的3个显著因素。在此基础上通过最陡爬坡实验逼近最大响应区域,并采用Box-Behnken实验设计及响应面分析确定了发酵产SAM的最佳条件为接种量10%,L-Met质量浓度为4.0g/L,发酵时间56h,发酵温度30℃,pH为6.0,在250mL三角瓶中装液量60mL,种龄24h,摇床转速180r/min。最终优化后的SAM胞内产量达到287.615 7mg/g,比初始产量提高1.38倍。 相似文献
110.