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The introduction of inexpensive microcomputer hardware and innovative user‐oriented software packages has had a significant impact on the traditional data processing procedures of the construction industry. Copyrighted electronic spreadsheet packages such as VisiCalc and SuperCalc are now available to practically all microcomputer users. These spreadsheet packages provide construction contractors, owners and managers with a versatile management tool that can be applied to a wide range of construction‐related problems. The overall capabilities of spreadsheet packages are examined and specific applications of interest to the construction management community are presented. 相似文献
94.
The Hamming upper bound is a well known limit for binary codes. Extensions to multilevel codes involve a distinction between whole-digit errors and nearest-value errors. The generalised Hamming bound is derived from consideration of cosets. Application to quaternary and decimal codes are discussed. 相似文献
95.
Pulmonary angiograms and pulmonary lung perfusion scans on 162 patients with pulmonary embolism were comparatively analyzed. Among the expert angiographic panel members who independently evaluated the studies there was consistent agreement on the diagnosis, size of the emboli, and severity. Consistency of agreement among the expert pulmonary lung perfusion scan panelists was considerably less. These data demonstrate that, in addition to the lack of specificity of the lung perfusion scan for the diagnosis of pulmonary thromboemboli, there is a considerable problem of interpretation in this patient population. 相似文献
96.
Research in the 1960s demonstrated the capabilities of infants and the demand characteristics of their behavior. These data, together with the failure of studies directed exclusively to parent effects on children, have led to a reformulation of socialization theory to encompass the reciprocal influences of parent and offspring. The cognitive capabilities, knowledge, and attitudes of parents assume a more important role in this theory. New research approaches are now available that can isolate parent and child effects, thus providing the foundation needed for identifying reciprocal influences. If research fills in the outline of this new perspective, and the viewpoint is communicated to parents, it should facilitate parent–child interaction. Previous theories, all too often given extreme expression in the mass media, have adversely affected the functioning of parents, either causing them to feel too much responsibility for their children's development, or leading them to mistake permissiveness for parental involvement and commitment. The reformulation should attenuate these extreme formulations, because neither of the latter is consistent with the concept of reciprocal influences. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
An innovative model for organising social services in a community, the Imbrication Model, is contrasted with two traditional models, the Entrepreneurial and the Umbrella Agency. The structural characteristics and dynamics of the three models are illustrated with actual case histories. Imbrication Model calls for the interlocking of personnel from several agencies, with the purpose of redirecting the dysfunctional interagency rivalry prevalent in the traditional models. Imbrications at all organisational levels--Board of Directors, Administrators and Staff--facilitate adoption of the superordinate goal of providing clients with the best services available, regardless of which particular agency delivers the service. Few observers of the current social service scene would challenge the statement that needs for service are unlimited and resources limited. In the USA the imbalance between needs and resources persists despite a decade of massive governmental programmes intended to alleviate social ills. Recent substantial cutbacks in federal funds, moreover are not likely to improve the situation. The resource shortage involves more than a limitation of funds. Deliverers of service and competent programme administrators are also on critically short supply. These shortages are more often than not exacerbated by a chronic spirit of competition among agencies and programmes at the local level. Three organizational models for the delivery and administration of social services, two conventional and one of more recent date, are examined in this article. The innovative model, which has been named the Imbrication Model, explicitly calls for redirecting interagency rivalry and competition. Its ambitious goal is to integrate the efforts of those attempting to meet a community's social service needs. 相似文献
98.
T Kimura JK Toung S Margolis WR Bell JL Cameron 《Canadian Metallurgical Quarterly》1980,87(5):509-513
Hypertriglyceridemia has been noted in patients with acute pancreatitis and respiratory failure. Utilizing an isolated, perfused, canine pulmonary lobe, the effect of triglyceride infusion on pulmonary function was evaluated. When heparin was used to anticoagulate the perfusion circuit, the addition of triglyceride to the autologous blood perfusate resulted in massive weight gain (226 gm), intrapulmonary shunting (36%), and a marked drop in pulmonary compliance (congruent to 50%). Heparin activates lipoprotein lipase, and therefore some triglyceride in the perfusate was lipolyzed with a resultant increase in serum free fatty acids (FFAs) to 253 mumole/dl. When anticoagulation of the perfusion circuit was accomplished by defibrinogenation with Arvin, the addition of triglyceride to the autologous blood perfusate caused minimal weight gain (28 gm), no intrapulmonary shunting, and only a slight decrease in pulmonary compliance (22%). Arvin has no effect on lipoprotein lipase, and the FFA level in the perfusate remained normal (less than 70 mumole/dl). Thus it appears that FFA release secondary to the action of pulmonary lipoprotein lipase on blood triglyceride is the important pathogenic step in the induction of respiratory failure in this model. 相似文献
99.
24 Ss participated in two experiments in which they were required to pick out, from printed panels containing 16 dials, the dial with a deviating pointer. Two versions of a uniformly-aligned configuration and one version of a symmetrically-aligned configuration were studied. S was required to identify both the "different" dial and the direction of the deviating pointer. It was found that (1) both configurations were equally effective for check reading after extended practice, (2) early in practice symmetrical alignment configurations appear to be more difficult, (3) transfer effects from pointer symmetry to uniform alignment are greater than transfer effects in the other direction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.