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991.
Langlois Judith H.; Ritter Jean M.; Casey Rita J.; Sawin Douglas B. 《Canadian Metallurgical Quarterly》1995,31(3):464
The relations between infant attractiveness and maternal behavior were examined by observing mothers feeding and playing with their firstborn infants while they were still in the hospital after giving birth (N?=?144) and again when the infants were 3 months of age (N?=?115). The attitudes of the mothers toward their infants were also assessed. Mothers of more attractive infants were more affectionate and playful compared with mothers of less attractive infants. In contrast, the mothers of less attractive infants were more likely to be attentive to other people rather than to their infant and to engage in routine caregiving rather than affectionate behavior. The attitudes of the mothers of less attractive infants were also more negative than those of mothers of more attractive infants, but the number of differences in attitudes was not as great as the behavioral differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Using steady-state simulation, we have evaluated the effect of boiler superheat and reheat temperatures on the economics of the utility section of a Bayer Alumina Plant. These economics were compared with those of a steam plant which purchased power. Under this study's nominal economic conditions, producing steam and purchasing electricity was the cheaper option. A sensitivity analysis showed that the cogeneration plant became the better choice when the local cost of electricity rose above 10C/kWh. The plant economics improved monotonically with superheat temperature as did the thermo-dynamic efficiency. However, for reheat, the plant economics did not improve monotonically with temperature even though the thermodynamic eficiency did; thus improvement in the thermodynamic efficiency does not always yield improved economics. 相似文献
993.
This study examined effects of reward and response costs on the ability of 19 attention-deficit hyperactivity disorder (ADHD) and 17 control children to inhibit responding. Children were tested under 4 reinforcement conditions on a go/no-go learning task developed by J. P. Newman, C. S. Widom, and S. Nathan (1985). Two conditions involved both reward and response costs, 1 response costs only, and 1 reward only. ADHD children made more commission errors than controls across the 4 conditions. Analyses of learning curves indicated that group differences became larger on later trials. Thus, impaired inhibition was more generalized in ADHD children than in the psychopaths and extraverts studied by Newman and colleagues, and it became most evident when the children were required to improve learning across trials. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Optical Fluorescence and Its Application to an Intravascular Blood Gas Monitoring System 总被引:2,自引:0,他引:2
Gehrich John L. Lubbers Dietrich W. Opitz Norbert Hansmann Douglas R. Miller William W. Tusa James K. Yafuso Maseo 《IEEE transactions on bio-medical engineering》1986,(2):117-132
Optical fluorescence has an extensive history of application in the laboratory to the measurement of ionic concentrations and the partial pressures of oxygen and carbon dioxide. The use of optical fluorescence based sensors to fulfill a recognized need for continuous invasive monitoring of arterial blood gases offers a number of inherent advantages. However, the requirements placed upon a blood gas probe and supporting instrumentation appropriate for use in the clinical environment result in significant design challenges in selection of suitable fluorescent dyes, maintenance of mechanical integrity while obtaining required miniaturization of sensors, and in the transmission, acquisition, and processing of low level light signals. An optical fluorescence based intravascular blood gas monitoring system has been developed which is particularly suited for the critical care and surgical settings and which has a sensor probe that can be introduced into the patient via a radial artery catheter. This system has shown an excellent agreement of measured with true values of pH, pCO2, and P02 in both in vitro and animal studies. Linear regression analysis of typical in vitro data, where true levels were established via tonometry and standardization to a high accuracy laboratory pH measuring instrument, shows slope/intercept values very close to 1.0/0.0 and correlation coefficients of greater than 0.99 for all three parameters. 相似文献
995.
Clark W. Crawford; Carroll J. Douglas; Yang Joseph C.; Janal Malvin N. 《Canadian Metallurgical Quarterly》1986,12(1):103
Used the individual differences scaling model of multidimensional scaling to explore the dimensions of thermal pain. 20 male undergraduates made 66 similarity judgments to all pairs of 12 different thermal stimulus intensities ranging from zero to noxious. Results reveal a 2-dimensional group stimulus space. The major dimension ordered the stimuli with respect to their intensity. This quantitative, strength-of-sensation dimension may be interpreted as indicating how weak or strong a stimulus feels, apart from any secondary qualities of warmth or pain. The 2nd dimension was related to the qualitative aspects of the stimuli and contained 2 attributes: (1) a pain attribute ranging from just detectable warmth to painful and (2) a warm–hot attribute running from just detectable warmth to hot. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Perceptions of marital interactions were gathered from a representative sample of urban newlywed couples (199 Black and 174 White). A factor analysis of the reports found 6 factors common to husbands and wives: Disclosing Communication, Affective Affirmation, Negative Sexual Interaction, Traditional Role Regulation, Destructive Conflict, and Constructive Conflict. Avoiding Conflict was specific to men and Positive Coorientation was specific to women. Wives reported fewer constructive and destructive conflict behaviors. Compared with Whites, Blacks reported more disclosure, more positive sexual interactions, and fewer topics of disagreement. They also more often reported leaving the scene of conflict and talking with others more easily than with the spouse. As hypothesized, perceptions that marital interactions affirm one's sense of identity strongly predicted marital well-being. Although regression analyses predicting marital happiness yielded few interactions with race or gender, those that are significant, coupled with race and gender differences in perceiving interaction, suggest taking a contextual orientation to the meaning of marital interaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
The domain reduction method uses a finite group of symmetries of a system of linear equations arising by discretization of partial differential equations to obtain a decomposition into independent subproblems, which can be solved in parallel. This paper develops a theory for this class of methods based on known results from group representation theory and algebras of finite groups. The main theoretical result is that if the problem splits into subproblems based on isomorphic subdomains, then the group of symmetries must be commutative. General decompositions are then obtained by nesting decompositions based on commutative groups of symmetries. 相似文献
998.
999.
1000.
Weisz John R.; Weiss Bahr; Han Susan S.; Granger Douglas A.; Morton Todd 《Canadian Metallurgical Quarterly》1995,117(3):450
A meta-analysis of child and adolescent psychotherapy outcome research tested previous findings using a new sample of 150 outcome studies and weighted least squares methods. The overall mean effect of therapy was positive and highly significant. Effects were more positive for behavioral than for nonbehavioral treatments, and samples of adolescent girls showed better outcomes than other Age?×?Gender groups. Paraprofessionals produced larger overall treatment effects than professional therapists or students, but professionals produced larger effects than paraprofessionals in treating overcontrolled problems (e.g., anxiety and depression). Results supported the specificity of treatment effects: Outcomes were stronger for the particular problems targeted in treatment than for problems not targeted. The findings shed new light on previous results and raise significant issues for future study. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献