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91.
Water movements due to temperature gradients and short-term water level fluctuations control the flushing timescale of the many shallow embayments in the Great Lakes. In this article the water circulation within Frenchman's Bay is reported and estimates made of the hydraulic flushing timescale. This shallow freshwater embayment is permanently connected to Lake Ontario through a channel of width 30 m and depth of 2 m. The water flushing timescale is estimated by using a salt mass budget, leading to a flushing timescale of 7–10 days. During the summer, the exchange of water between the bay and the lake can be driven by a combination of horizontal thermal gradients, and by small but ubiquitous 1–5 cm oscillations in the water level of Lake Ontario. The water movements that are predicted due to water level fluctuations (caused by seiches, storm surges and tides) and due to horizontal thermal gradients leads to estimates of the flushing time of water within Frenchman's Bay in the range of 12–13.5 days, i.e. the same order of magnitude as the salt budget. One consequence of the temperature driven exchange flows is to cause strong and persistent temperature stratification within the bay, which in combination with high nutrient loading and low winds in summer leads to frequent anoxic events.  相似文献   
92.
We calculated the wet and dry deposition, vapor absorption, and volatilization flows (in kg/yr) of seven polychlorinated biphenyls (PCBs), nine organochlorine pesticides, and two polycyclic aromatic hydrocarbons (PAHs) into and out of the Great Lakes during 2010–2015 (inclusive). Particle, vapor, and precipitation concentrations from five rural and remote stations (one site on each lake) and two urban sites, operated by the United States and Canada, were used for the flow calculations. Output from the water to the air was the most important process for PCBs, chlordanes, and p,p′-DDE. The flows of endosulfan, p,p′-DDT, and phenanthrene were dominated by vapor absorption from the air to the water. The flow of benzo[a]pyrene was controlled by wet and dry deposition to the water. The flows of the hexachlorocyclohexanes (HCHs) into and out of the lakes were about equal, indicating air-water equilibrium for these compounds. Among the lakes, Lakes Superior and Erie had the highest input and output flows. The input and output flows for the five lakes were decreasing with halving times of 1–10 years and 10–40 years, respectively. Most chemicals had seasonal variations in their flows, with maximum inputs in the summer and maximum outputs in the fall. The flows of PCBs and PAHs into Lakes Michigan and Erie were associated with Chicago and Cleveland, respectively. Combining our data with previous data over the period 1992–2015, we estimated that the input flows of most of these chemicals have significantly decreased, but the output flows do not show consistent trends.  相似文献   
93.
A recent review of the Great Lakes Water Quality Agreement has concluded that while controls on phosphorus inputs to Lake Michigan achieved the desired effect in offshore waters, the nearshore region continues to suffer from elevated phosphorus levels. Failure to achieve trophic state goals in the nearshore is manifested in nuisance growth of Cladophora and attendant impacts on property owners, utilities, and the public health and welfare. This study focuses on a site in Lake Michigan near Milwaukee, Wisconsin, where nuisance growth of Cladophora and associated beach fouling occur regularly. A mechanistic model simulating Cladophora growth, suitable for guiding nutrient management in the Great Lakes nearshore, is presented. The model represents an update of the Canale and Auer framework, reflecting current understandings of Cladophora ecology and offering a user-friendly interface making the software more widely available to decision makers. This Great Lakes Cladophora Model (GLCM) is first validated for the Auer/Canale data set collected in 1979 at a site on Lake Huron and then for a data set developed in 2006 for a site on Lake Michigan. Model performance under the strikingly different forcing conditions (depth, light, phosphorus levels) characteristic of these two sites affirms the widespread applicability of the tool. The GLCM is then extended to examine the impacts of ecosystem perturbation (dreissenid colonization) on Cladophora growth and to future approaches to monitoring and management.  相似文献   
94.
The sol-gel process, using aqueous solutions, is used for dip coating onto substrates of 316L stainless steel. A suitable coating of LiCoO2 is achieved by varying the thickness and heat treating at 650℃ for 3 h. Thermal analysis, X-ray diffraction analysis and SEM are carried out to characterize the microstructure of the coatings. The results show that the coating transforms from an amorphous gel to crystalline phases above 350℃, and show a porous structure. The phase transition mechanism is discussed.  相似文献   
95.
Multi‐material polymer scaffolds with multiscale pore architectures are characterized and tested with vascular and heart cells as part of a platform for replacing damaged heart muscle. Vascular and muscle scaffolds are constructed from a new material, poly(limonene thioether) (PLT32i), which meets the design criteria of slow biodegradability, elastomeric mechanical properties, and facile processing. The vascular–parenchymal interface is a poly(glycerol sebacate) (PGS) porous membrane that meets different criteria of rapid biodegradability, high oxygen permeance, and high porosity. A hierarchical architecture of primary (macroscale) and secondary (microscale) pores is created by casting the PLT32i prepolymer onto sintered spheres of poly(methyl methacrylate) (PMMA) within precisely patterned molds followed by photocuring, de‐molding, and leaching out the PMMA. Prefabricated polymer templates are cellularized, assembled, and perfused in order to engineer spatially organized, contractile heart tissue. Structural and functional analyses show that the primary pores guide heart cell alignment and enable robust perfusion while the secondary pores increase heart cell retention and reduce polymer volume fraction.  相似文献   
96.
[Correction Notice: An erratum for this article was reported in Vol 7(3) of Psychological Services (see record 2010-17074-004). The copyright for the article was listed incorrectly. This article is in the Public Domain. The online version has been corrected.] The present study examined interest in family involvement in treatment and preferences concerning the focus of family oriented treatment for veterans (N = 114) participating in an outpatient Veterans Affairs outpatient posttraumatic stress disorder (PTSD) program. Most veterans viewed PTSD as a source of family stress (86%) and expressed interest in greater family involvement in their treatment (79%). These results suggest the need to consider increasing family participation in the clinical care of individuals with PTSD and to develop specialized family educational and support services for this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
98.
This study addresses the issue of domain specificity within creativity by understanding the characteristics of creative tasks and how participants react to the task. Participants (N = 187) were given 1 of 3 realistic everyday problems to solve. The problems differed in terms of complexity, involvement, and problem-based efficacy. Problem solutions were evaluated on several measures of creativity. Results indicate that creativity was influenced by the type of problem solved and the measure of creativity used to evaluate the solution. Furthermore, these results were obtained after controlling for the effect of ability. Results imply that not all real-world problems are equivalent and that researchers need to investigate how reactions to different problems and the creativity index used may influence conclusions regarding creative problem solving. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
100.
This study examined the relationship of early alliance ruptures and their resolution to process and outcome in a sample of 128 patients randomly assigned to 1 of 3 time-limited psychotherapies for personality disorders: cognitive–behavioral therapy, brief relational therapy, or short-term dynamic psychotherapy. Rupture intensity and resolution were assessed by patient- and therapist-report after each of the first 6 sessions. Results indicated that lower rupture intensity and higher rupture resolution were associated with better ratings of the alliance and session quality. Lower rupture intensity also predicted good outcome on measures of interpersonal functioning, while higher rupture resolution predicted better retention. Patients reported fewer ruptures than did therapists. In addition, fewer ruptures were reported in cognitive–behavioral therapy than in the other treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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