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71.
This paper examines security of supply concerns in an Australian electricity market under transition and considers potential policy pathways to address them. It details the current state of Australia’s electricity industry, considers the extent to which supply security in the electricity sector may be considered a public good, and examines the features likely to impact on the efficacy of current and potential future market designs. 相似文献
72.
Xiao‐Dong Hu Shawn E. Jenkins Byung G. Min Malcolm B. Polk Satish Kumar 《大分子材料与工程》2003,288(11):823-843
Synthesis, structure, and properties of rigid‐rod polymers with special emphasis on poly(p‐phenylene benzobisoxazole) (PBO) and poly(p‐phenylene benzobisthiazole) (PBZT) have been reviewed. Recent studies on chemical modifications and molecular simulations have also been given. After nearly 20 years of research and development, PBO fiber was commercialized in the late 1990s. However, due to processing difficulties, the concept of the so called molecular composites has not been successful. Development of the high compressive strength M5 and dihydroxy‐PBI fibers clearly suggest that there is potential for further developing properties of this class of materials. Opto‐electronic properties have also been reviewed.
73.
Carbamoyl chlorides are important intermediates, both in the research laboratory and in industrial scale syntheses. The most studied and used are the disubstituted derivatives, incorporating either aryl or alkyl groups (Ar2NCOCl or R2NCOCl). Sometimes, the groups are tied back to give a ring and piperidino- and morpholino-derivatives are commonly encountered. Some studies have been made with two different groups attached. Solvolyses tend to occur at the carbonyl carbon, with replacement of the chloride ion. Studies of both rate and products are reviewed and the solvolysis reactions are usually SN1, although addition of an amine leads to a superimposable bimolecular component. Many of the studies under solvolytic conditions include the application of the extended Grunwald–Winstein equation. The monosubstituted derivatives (ArNHCOCl or RNHCOCl) are less studied. They are readily prepared by the addition of HCl to an isocyanate. In acetonitrile, they decompose to set up and reach equilibrium with the isocyanate (ArNCO or RNCO) and HCl. Considering that the structurally related formyl chloride (HOCOCl) is highly unstable (with formation of HCl + CO2), the unsubstituted carbamoyl chloride (H2NCOCl) is remarkably stable. Recommended synthetic procedures require it to survive reaction temperatures in the 300–400 °C range. There has been very little study of its reactions. 相似文献
74.
Published online: 14 May 2002 相似文献
75.
Gordon Rugg Malcolm Eva Atiya Mahmood Nazia Rehman Stephanie Andrews & Sarah Davies 《Information Systems Journal》2002,12(3):215-229
Abstract. Eliciting information about organizational culture is an important part of system analysis and design. However, eliciting knowledge of this sort is difficult. Laddering is an established technique that is particularly suitable for eliciting information about goals and for eliciting explanations, which are important issues when investigating organizational culture. This paper describes the method, its strengths and limitations, its use in several case studies and its relation to other elicitation techniques. Recommendations for further work are given. 相似文献
76.
This research tests and develops the Technology Acceptance Model (TAM), introduced by Davis (1986), which attempts to explain end users' attitudes to computing technologies. It introduces several new variables, including compatibility, user characteristics, system rating and the enduser computing satisfaction (EUCS) construct, a surrogate measure for IT success and acceptance. A questionnaire with over seventy items was completed by a large number of users and LISREL, a technique for modelling a system of structural equations, was used to analyse the responses. The output shows the model as a whole fits the data very well and indicates significant relationships between variables in the model. These results confirm that TAM is a valuable tool for predicting attitudes, satisfaction, and usage from beliefs and external variables. They also show that relative advantage of the system contributed most to attitudes and satisfaction. Compatibility (of the system to the task performed) contributed most to usage and was the most important antecedent of the belief variables, including relative advantage. 相似文献
77.
Over the last decade, MALDI-MS imaging has been used by researchers to explore areas of proteomics, lipidomics and metabolomics in samples of clinical origin for both targeted and global biomarker analysis. Numerous technological advancements in MS and clinical tissue MS imaging have been accomplished; hence, in this article we aim to critically discuss whether MS imaging has now in fact become a true champion of the ‘Omics Era’. In order to assess the potential for it to be routinely used in the clinical setting, it is pertinent to discuss some of its limitations, and to examine how these have been addressed by researchers. The key limitations of the technique we will discuss in this viewpoint article are as follows: sample throughput; relevance to patients, the availability of validated/standardised techniques; and integration with conventional pathology and other medical imaging techniques. Good progress has been made over the last 5 years in overcoming these limitations that had previously restricted the use of this technology in the clinical setting. 相似文献
78.
Published online: 14 May 2002 相似文献
79.
Laura Moss Derek Sleeman Malcolm Sim Malcolm Booth Malcolm Daniel Lyndsay Donaldson Charlotte Gilhooly Martin Hughes John Kinsella 《Knowledge》2010,23(4):309-315
Within the medical domain there are clear expectations as to how a patient should respond to treatments administered. When these responses are not observed it can be challenging for clinicians to understand the anomalous responses. The work reported here describes a tool which can detect anomalous patient responses to treatment and further suggest hypotheses to explain the anomaly. In order to develop this tool, we have undertaken a study to determine how Intensive Care Unit (ICU) clinicians identify anomalous patient responses; we then asked further clinicians to provide potential explanations for such anomalies. The high level reasoning deployed by the clinicians has been captured and generalised to form the procedural component of the ontology-driven tool. An evaluation has shown that the tool successfully reproduced the clinician’s hypotheses in the majority of cases. Finally, the paper concludes by describing planned extensions to this work. 相似文献
80.
This paper considers the design of feedback controllers for linear, time-invariant, spatially distributed systems in an approach which generalises the H∞-framework and in particular the H∞ loop-shaping method. To this end, we introduce a class of spatially distributed system models called finite dimensional, distributed, linear, time-invariant systems. Sensors and actuators are considered to be part of the controller, rather than part of the plant, and thus the controller we wish to design is itself a spatially distributed system. Optimising over placements and shapes of the sensor and actuator spatial distribution functions is an integrated part of the controller design procedure. As an illustrative design example, we present the feedback stabilisation of an electrostatically destabilised, electrically conducting membrane. 相似文献