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排序方式: 共有2120条查询结果,搜索用时 62 毫秒
961.
Rebecca L. KingGerardine G. Botte 《Journal of power sources》2011,196(22):9579-9584
It has been shown that urea electrolysis is a viable method for wastewater remediation and simultaneous production of valuable hydrogen. Inexpensive nickel catalyst is optimal for the oxidation of urea in alkaline media but improvements are needed to minimize surface blockage and increase current density. Multi-metal catalysts were investigated by depositing platinum group metals on a nickel substrate. Rhodium and nickel proved synergistic to reduce surface blockage and increase catalyst stability. Rh-Ni electrodes reduced the overpotential for the electro-oxidation of urea and improved the current density by a factor of 200 compared to a Ni catalyst. 相似文献
962.
Rebecca L. KingGerardine G. Botte 《Journal of power sources》2011,196(5):2773-2778
A technology was demonstrated for the production of hydrogen and other valuable products (nitrogen and clean water) through the electrochemical oxidation of urea in alkaline media. In addition, this process remediates toxic nitrates and prevents gaseous ammonia emissions. Improvements to urea electrolysis were made through replacement of aqueous KOH electrolyte with a poly(acrylic acid) gel electrolyte. A small volume of poly(acrylic acid) gel electrolyte was used to accomplish the electrochemical oxidation of urea improving on the previous requirement for large amounts of aqueous potassium hydroxide. The effect of gel composition was investigated by varying polymer content and KOH concentrations within the polymer matrix in order to determine which is the most advantageous for the electrochemical oxidation of urea and production of hydrogen. 相似文献
963.
ABSTRACT Alfalfa juice was extracted from plants during the graving phases of the first and second crops. The alfalfa juice was dried and solute concentrations were measured periodically during the process using freezing point depression (FPD) as an indicator. Solute/solvent weight ratios were calculated from the freezing point depression of fresh unconcentrated 'uice extracted from both firsc and second crops. At the time of harvest, tie FPD was a function of this ratio. The first and second crops behaved distinctively different during the drying process, with the second having a larger soluce concentration and a greater FPD at a given moisture content. The appearance of preci itate during the drying process and the general1 large FPD makes this materiay a questionable product for drying vitg low temperature processes. 相似文献
964.
Nyasha Allen Lisa J. White Jessica E. Boles Dr. George T. Williams Dr. Dominique F. Chu Rebecca J. Ellaby Dr. Helena J. Shepherd Kendrick K. L. Ng Laura R. Blackholly Ben Wilson Prof. Daniel P. Mulvihill Dr. Jennifer R. Hiscock 《ChemMedChem》2020,15(22):2193-2205
Herein we report 50 structurally related supramolecular self-associating amphiphilic (SSA) salts and related compounds. These SSAs are shown to act as antimicrobial agents, active against model Gram-positive (methicillin-resistant Staphylococcus aureus) and/or Gram-negative (Escherichia coli) bacteria of clinical interest. Through a combination of solution-state, gas-phase, solid-state and in silico measurements, we determine 14 different physicochemical parameters for each of these 50 structurally related compounds. These parameter sets are then used to identify molecular structure-physicochemical property-antimicrobial activity relationships for our model Gram-negative and Gram-positive bacteria, while simultaneously providing insight towards the elucidation of SSA mode of antimicrobial action. 相似文献
965.
Lawrence Erika; Barry Robin A.; Brock Rebecca L.; Bunde Mali; Langer Amie; Ro Eunyoe; Fazio Emily; Mulryan Lorin; Hunt Sara; Madsen Lisa; Dzankovic Sandra 《Canadian Metallurgical Quarterly》2011,23(1):44
Relationship satisfaction and adjustment have been the target outcome variables for almost all couple research and therapies. In contrast, far less attention has been paid to the assessment of relationship quality. The present study introduces the Relationship Quality Interview (RQI), a semistructured, behaviorally anchored individual interview. The RQI was designed to provide a more objective assessment of relationship quality as a dynamic, dyadic construct across 5 dimensions: (a) quality of emotional intimacy in the relationship, (b) quality of the couple's sexual relationship, (c) quality of support transactions in the relationship, (d) quality of the couple's ability to share power in the relationship, and (e) quality of conflict/problem-solving interactions in the relationship. Psychometric properties of RQI ratings were examined through scores obtained from self-report questionnaires and behavioral observation data collected cross-sectionally from a sample of 91 dating participants and longitudinally from a sample of 101 married couples. RQI ratings demonstrated strong reliability (internal consistency, interrater agreement, interpartner agreement, and correlations among scales), convergent validity (correlations between RQI scale ratings and questionnaire scores assessing similar domains of relationship quality), and divergent validity (correlations between RQI scale ratings and (a) behavioral observation codes assessing related constructs, (b) global relationship satisfaction scores, and (c) scores on individual difference measures of related constructs). Clinical implications of the RQI for improving couple assessment and interventions are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
966.
To examine the predictors of adolescents' evaluations of affirmative action and school desegregation policies, African American and European American students (ns = 94 and 116, respectively; aged 14 to 17 years) attending a racially diverse high school in the Midwestern United States completed measures of (a) implicit racial attitudes, (b) knowledge about historical racism, and (c) perceptions of and attributions for racial disparities. The following day, adolescents learned about either a proposed affirmative action policy (n = 101) or a school desegregation policy (n = 109) and completed measures of their attitudes toward the policy. Results indicated racial differences in policy support and in the factors predicting policy support. Theoretical implications of the findings are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
967.
968.
Justine McNamara Rebecca Cassells Philippa Wicks Yogi Vidyattama 《Housing Studies》2010,25(5):625-646
The importance of suitable, affordable housing in promoting the well-being of children is widely acknowledged. However, despite growing interest in geographic differences in child well-being, little is known about the spatial distribution of characteristics associated with housing disadvantage for Australian children. This paper seeks to develop knowledge in this area by creating a headline indicator of child housing disadvantage. It uses spatially disaggregated Census data from the Australian Bureau of Statistics (ABS) Census of Population and Housing 2006 capturing overcrowding, public housing tenure and dwelling type, and creates synthetic estimates of housing stress using spatial microsimulation techniques. These variables are then combined into a single index of housing disadvantage. Next, the spatial microsimulation techniques and index creation methodology are described, and the results of the validation process, including sensitivity analysis of alternative index creation approaches, are presented. 相似文献
969.
Rebecca Esche Alessandro Carcelli Andreas Barnsteiner Stefano Sforza Karl-Heinz Engel 《European Food Research and Technology》2013,236(6):999-1007
Qualitative and quantitative methods for the analysis of intact phytosteryl/phytostanyl esters in enriched dairy products with substantial amounts of protein and fat were established. Lipids were extracted after acid digestion in order to achieve a complete extraction of the esters. The extracted lipids were separated via liquid chromatography on a normal phase, and the fraction containing the phytosteryl/phytostanyl esters was subsequently transferred on-line and analyzed by means of capillary gas chromatography. The applicability of the method was demonstrated for the analysis of intact phytosteryl/phytostanyl fatty acid esters in enriched yogurt, cheese-based spread, and milk. The approach enables the determination of individual phytosteryl/phytostanyl esters as well as of their total contents and provides detailed information on the distributions of esterified phytosterols/phytostanols and fatty acids. The employed approach complements the existing GC-based methods for the analysis of phytosteryl/phytostanyl esters in low-fat and fat-based products and thus creates a base for authenticity assessments of these types of novel foods. 相似文献
970.
Qing‐Yuan Tang Yan‐Cheong Chan Ning‐Bew Wong Rebecca Cheung 《Polymer International》2010,59(9):1240-1245
The dispersion and stability of carbon nanotubes (CNTs) inside a polymer matrix, especially with a high CNT content, are still big challenges. Moreover, the interaction between CNTs and the polymer matrix should be strong enough to improve the mechanical properties. The efficient dispersion of CNTs is essential for the formation of a uniform distribution of a CNT network in a polymer composite. Polyimide/multiwall CNT nanocomposites were synthesized by in situ polymerization with the aid of a surfactant. A Fourier transform infrared spectroscopy study proved that the surfactant did not hamper the polymerization of the polyimide. The microstructure, storage modulus and electrical conductivity of the nanocomposites were improved using a particular amount of the surfactant. Environmental stability test results showed that the polyimide with 1 wt% of CNTs produced with the aid of the surfactant possessed excellent reliability in high‐temperature and high‐humidity environments. Surfactants were successfully used to obtain fine‐structure polyimide/CNT nanocomposites by in situ polymerization. The enhancement of the mechanical properties was attributed to the incorporation of the surfactant. A percolation of electrical conductivity could be achieved with 1 wt% of CNTs. Copyright © 2010 Society of Chemical Industry 相似文献