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951.
Monosodium methanearsonate (MSMA) is frequently used as an herbicide for the control of weeds in turf grasses at golf courses in Florida. There are concerns about arsenic (As) contamination of local shallow groundwater from the application of MSMA. The distinction between "free" As and colloid-bound/complexed As in soil solution is important for understanding the mobility and bioavailability of As in the environment. In this study, the equilibrium membrane (500 and 3500 Da) dialysis method was employed to determine the "free" and "bound" As in water extracts of five types of golf-course soils containing coated and uncoated sands in various proportions with peat. All samples were evaluated for arsenic species (arsenite, AsIII and arsenate, AsV), dissolved organic matter, and additional constituents (iron, aluminum, and calcium). The impacts of microbial growth were evaluated by conducting experiments with and without the addition of sodium azide for one particular soil type. Results indicate that (1) the presence of peat in the soils plays a significant role in the distribution of As in the dissolved phase of soil solutions; (2) the majority of As present in the soil extracts from soils containing peat was associated with substances of molecular weight (MW) between 500 and 3500 Da; (3) the association of As and dissolved organic matter (DOM) in the soil solution strongly affected As bioavailability, thus determining As transformations via microorganism-mediated processes; and (4) the presence of peat greatly enhanced the release of iron, aluminum, and calcium from soil. Amendment of sand with peat is a common practice at Florida golf courses. However, the addition of peat will alter the properties of the soils, which in turn could affect As transport and transformation. The results of this study are useful for understanding the factors controlling As trapping and transport within porous soil media and in developing comprehensive plans for managing and remediating As contaminated environments, such as golf courses.  相似文献   
952.
During the past decade, government agencies have struggled to adequately respond to emergency events that require labor, materials, equipment, and services provided by construction contractors. In fact, the criticism directed at government agencies during their response to, and recovery after, recent events is a testament to the insufficient contracting strategies that were implemented. Countless media headlines highlighted the fragmented approach used to hire contractors expeditiously, and several agencies were criticized for their inconsistent contracting methods. As a result, a study was initiated to investigate the differences between normal federal contracting procedures, as outlined in the Federal Acquisition Regulation (FAR), and emergency acquisition procedures that are permitted by the FAR. The study found six examples of waivers to the usual regulations or expedited contracting techniques permitted by the FAR. Furthermore, the study highlighted five emergency contract strategies that are available to the Navy (as one example of a government agency with contracting authority) and may be available to other governmental contracting authorities as well. Consequently, the purpose of this paper is to identify emergency contract strategies that can be used by government agencies and to outline the criteria that must be met to use each strategy.  相似文献   
953.
IT systems for engineers are becoming more numerous and complex and will further proliferate in the future. It is infeasible to expect users to be trained to work with a plethora of systems, especially as many of them will only see occasional use. Therefore, in the near future, systems will need user interfaces that allow intuitive access and usage. This paper examines a new style of user interface based on virtual reality.  相似文献   
954.
Stigma theory was used to examine the fears underlying the disclosure of a gay identity at work. Using a national sample of 534 gay, lesbian, and bisexual employees, this study examined the antecedents that affect the degree of disclosure of a gay identity at work and, for those who had not disclosed, the factors that influence their fears about full disclosure. Employees reported less fear and more disclosure when they worked in a group that was perceived as supportive and sharing their stigma. Perceptions of past experience with sexual orientation discrimination were related to increased fears but to greater disclosure. For those who had not fully disclosed their stigma, the fears associated with disclosure predicted job attitudes, psychological strain, work environment, and career outcomes. However, actual disclosure was unrelated to these variables. The utility of fear of disclosure for understanding processes underlying the disclosure of gay and other invisible stigmatized identities in the workplace is discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
955.
Meta-analysis was used to integrate research on the relations between parental socialization behavior and child and adolescent physical activity (PA) levels. Four major databases were examined: PubMED, ERIC, Web of Science, and PsychLit (1960 -2005). Thirty studies met the following inclusion criteria: (a) child age (2-18 years) and (b) statistical information permitting calculation of an effect size between parent socialization behavior and child PA. Mean age of participants across studies ranged from 2.54 to 15.5 years. The unweighted mean and median effect sizes (as indexed by r) were .17 and .13, respectively, indicating that a moderate positive relation exists between parental support and modeling behavior and child and adolescent PA levels. The moderating effect of type of parental socialization behavior, population characteristics, and methodological factors were investigated. Theoretical and methodological implications concern the inclusion of mediated models of parental influence and the use of longitudinal investigations in determining causal direction. From an applied viewpoint, these results are useful for the design of future, more effective childhood obesity prevention programs by suggesting child-age-appropriate parental influences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
956.
The rising costs of new psychological tests, increased frequency of test revisions, and difficulty receiving authorization and reimbursement from managed care companies make it increasingly difficult for practitioners to provide the best standard of care to clients when conducting psychological and neuropsychological assessments. Practitioners, especially those in low-income and rural areas, may struggle with handling these practical realities while maintaining ethical standards in conducting psychological assessment. Suggestions for how to manage practical challenges faced by practitioners who provide psychological assessments, such as selecting tests when authorization or reimbursement by a third-party payer is restricted or denied, purchasing psychological tests on a budget, and providing assessments with a limited number of qualified staff are discussed. The authors also provide recommendations for the future prevention of these challenges through work with test developers, test publishing corporations, third-party payers, political action groups, and the psychology profession itself. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
957.
It has been more than four years since the last of my infrequent editorials in the International Journal of Stress Management (IJSM) and nearly a decade since my first (Carlson, 1998b). I am writing to you at this time first to inform you of a change in editorship, then to summarize a few high points of the past 10 years of IJSM as they relate to its management and future. My focus will be on matters dear to journal editors and useful to submitters and subscribers concerning submissions, content, and editorial activity, since such issues determine journal policy and direction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
958.
Objective: To test hypothesized relations between hope and self-efficacy for rehabilitation to depression and functional ability reported by individuals receiving joint replacement surgery. Study Design: Community-dwelling older adults (N = 100) from an orthopaedic clinic were administered measures of hope, self-efficacy for rehabilitation, pain, depression, body mass index (BDI), and mental status 1 month prior to their joint replacement surgery. These measures were completed by 62 participants 6 weeks after surgery. Demographic, health information, and functional outcome measures were obtained by medical personnel pre- and postsurgery. Main Outcome Measures: Functional outcome measures (Harris Hip and Knee Society Scores) and depressive symptomatology. Results: Hope was significantly predictive of presurgery depression, but it was not predictive of depression or functional ability after surgery. Higher levels of self-efficacy were predictive of lower postsurgery depression scores. Conclusions: Results imply that social-cognitive constructs may have utility in the prediction of emotional adjustment before and after joint surgery, but they may have limited value in anticipating functional abilities following these surgeries. Theoretical and clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
959.
The Florida Department of Transportation (FDOT) is in the process of implementing Pontis, a Bridge Management System, to provide decision support to engineers in the headquarters and district offices as they make routine policy, programming, and budgeting decisions regarding the preservation and improvement of the state’s bridges. As part of this effort, an ongoing research program is underway to adapt the system to FDOT needs as well as to advance the state of the art in several areas important to the Department. Most of the research results are organized around a new project-level decision support framework that complements and builds on Pontis’ existing network-level analysis. Specific new models include accident risk and user cost due to roadway width and alignment deficiencies; user cost of load capacity and vertical clearance restrictions, and moveable bridge openings; project-level prediction models for bridge element condition and costs; and prediction of economics of scale and scoping possibilities. The new models are built into a highly graphical spreadsheet model for decision support use.  相似文献   
960.
People coordinate the force and direction of skilled actions with target locations and adjust the calibrations to compensate for changing circumstances. Are the adjustments globally organized (adjusting a particular action to fit a particular circumstance would generalize to all actions in the same circumstance); anatomically specific (every effector is adjusted independently of others); or functional (adjustments would generalize to all actions serving the same goal and generating the same perceptible consequences)? Across 10 experiments, changes in the calibration of walking, throwing, and turning-in-place were induced, and generalization of changes in calibration to functionally related and unrelated actions were tested. The experiments demonstrate that humans rapidly adjust the calibration of their walking, turning, and throwing to changing circumstances, and a functional model of perceptual-motor organization is suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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