首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   373篇
  免费   16篇
电工技术   17篇
化学工业   70篇
金属工艺   17篇
机械仪表   14篇
建筑科学   10篇
能源动力   13篇
轻工业   29篇
石油天然气   1篇
无线电   38篇
一般工业技术   62篇
冶金工业   62篇
原子能技术   3篇
自动化技术   53篇
  2023年   5篇
  2022年   12篇
  2021年   11篇
  2020年   7篇
  2019年   8篇
  2018年   10篇
  2017年   14篇
  2016年   9篇
  2015年   8篇
  2014年   16篇
  2013年   22篇
  2012年   14篇
  2011年   23篇
  2010年   16篇
  2009年   10篇
  2008年   14篇
  2007年   14篇
  2006年   12篇
  2005年   7篇
  2004年   15篇
  2003年   14篇
  2002年   6篇
  2001年   10篇
  2000年   9篇
  1999年   3篇
  1998年   25篇
  1997年   11篇
  1996年   3篇
  1995年   6篇
  1994年   10篇
  1993年   8篇
  1992年   5篇
  1991年   2篇
  1990年   4篇
  1989年   7篇
  1988年   1篇
  1987年   1篇
  1986年   4篇
  1985年   1篇
  1983年   1篇
  1982年   2篇
  1979年   1篇
  1977年   1篇
  1976年   5篇
  1973年   2篇
排序方式: 共有389条查询结果,搜索用时 15 毫秒
81.
This study investigates the role of high-dose chemotherapy with haematopoietic stem cell rescue as consolidation treatment in high-risk retinoblastoma (extraocular disease at diagnosis or relapse or invasion of cut end of optic nerve). 25 patients received high-dose chemotherapy including carboplatin (250 mg/m2/day from day 1 to day 5 for the 6 first patients and 350 mg/m2/day from day 1 to day 5 for the other patients), etoposide (350 mg/m2/day from day 1 to day 5) and cyclophosphamide (1.6 g/m2/day from day 2 to day 5) (CARBOPEC) followed by autologous haematopoietic stem cell rescue. 19 patients received this drug combination for chemosensitive extraocular relapse. The other 6 patients with histological high-risk factors were given this treatment as consolidation after enucleation and conventional chemotherapy. The three year disease-free survival was 67.1%. In 7 of the 9 relapsing patients, the first site of relapse was the central nervous system. All patients with central nervous system disease died except one. The main toxicity was haematological and digestive (mucositis and diarrhoea). 2 of the 13 evaluable patients had grade III and IV ototoxicity. One patient experienced an acute grade I reversible cardiotoxicity. The CARBOPEC regimen seems to be a promising therapeutic strategy in patients with high-risk retinoblastoma, especially those with bone and/or bone marrow involvement. This treatment did not improve the outcome of patients with central nervous system disease.  相似文献   
82.
Steels with ultrafine grains (lower than 5 μm), which usually known as ultrafine ferrite or ultrafine grained materials, are presently the object of intense research, because of the improvement in resistance and fracture toughness they may reach compared to conventional steels (with grain sizes above this value). It is shown that the forenamed steels designated in the Euronorm EN 10149-2, which are manufactured by advanced techniques of controlled rolling and mainly used in automotive industry, have an ultrafine grain size in the range of 2.5 to 3.5 μm, and with elastic yield stresses higher than 400 MPa. Based on the Morrison-Miller criterion, it is shown that values of the strain-hardening coefficient lower than 0.08 would make the industrial application of these steels unfeasible.  相似文献   
83.
In this paper, we propose a model for the energy consumption of the concurrent execution of three key dense matrix factorizations, with task parallelism leveraged via the Symmetric Multi‐Processing Superscalar (SMPSs) runtime, on a multicore processor. Our model decomposes the power dissipation into the system, static and dynamic components, with the former two being estimated from basic, off‐line experiments. The dynamic power, on the other hand, requires significantly more care, and we introduce a contention‐aware model that accommodates for the variability of power consumption due to memory contention. Experimental results on an Intel Xeon E5504 processor with four cores, using an internal powermeter that samples the power drawn by the mainboard with a frequency of 1 KHz, show the reliability of the energy model for the Cholesky, LU, and QR factorizations on this platform. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
84.
[Correction Notice: An erratum for this article was reported in Vol 31(3) of Psychotherapy: Theory, Research, Practice, Training (see record 2009-17141-002). This article contained, as Figure 1, an SASB model. The authorship and copyrights for the model were not acknowledged. The following acknowledgement should have been included: "Adapted from Benjamin (1984). Principles of Prediction using Structural Analysis of Social Behavior (SASB). In R. A. Zucker, J. Aronoff, and A. J. Rabin (Eds.), Personality and the Prediction of Behavior (pp. 121- 174). New York: Academic." An apology is offered to the author, Dr. Lorna Smith Benjamin. The particular version used in the article was developed in collaboration with Clinton W. McLemore.] Investigated the internalization of positive aspects of therapist–patient (TP) interactions among 70 patients and their 16 therapists who participated in a 5-yr study (H. H. Strupp et al, unpublished) of time-limited dynamic psychotherapy. Patients sought help for anxiety, depression, or other problems with a clear interpersonal component and qualified for an Axis I or Axis II diagnosis on the Diagnostic and Statistical Manual of Mental Disorders-III (DSM-III). Instruments included the Structural Analysis of Social Behavior and outcome measures of depression, anxiety, and psychological functioning. Patients' intrapsychic functioning became more similar to interpersonal activity in the TP relationship over the course of psychotherapy. Intrapsychic movement toward interpersonal activity in the TP relationship was associated with positive outcome on measures of depression, anxiety, and on independent clinician ratings of patient psychological functioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
Multi-objective optimization problems are often subject to the presence of objectives that require expensive resampling for their computation. This is the case for many robustness metrics, which are frequently used as an additional objective that accounts for the reliability of specific sections of the solution space. Typical robustness measurements use resampling, but the number of samples that constitute a precise dispersion measure has a potentially large impact on the computational cost of an algorithm. This article proposes the integration of dominance based statistical testing methods as part of the selection mechanism of evolutionary multi-objective genetic algorithms with the aim of reducing the number of fitness evaluations. The performance of the approach is tested on five classical benchmark functions integrating it into two well-known algorithms, NSGA-II and SPEA2. The experimental results show a significant reduction in the number of fitness evaluations while, at the same time, maintaining the quality of the solutions.  相似文献   
86.
The Journal of Supercomputing - Despite that IoT technology provides a promising future for human life, some significant challenges such as routing, security, low-cost equipment, energy...  相似文献   
87.
88.
89.
90.
Titania Degussa P25 powder was treated with Argon (Ar) and Nitrogen (N2) gas plasma inside of a closed homemade chamber system at 50 Pa of pressure. The electric discharge was generated applying an AC voltage (0–15,000 V) to a pair of aluminum electrodes. Two sets of samples were analyzed. In the first one, the plasma is applied directly on a layer of titania P25 that is spread out on top of one of the electrodes and, in the second one, a gold foil substrate is positioned between the titania powder and the electrode, named TiO2/Au. In the last sample, gold coated titania nanoparticles or clusters of gold are formed, changing the optical properties of the material. The evolution of the optical properties of the obtained samples was analized using UV–Vis diffuse reflectance. The spectra show a shift in the band gap and a broad band in P25/Au associated with the gold plasmonic band. Additionally, the photocatalytic activity was evaluated by monitoring the photodegradation of methylene blue solution (0.01 g/L), using UV–Vis absorption analysis in the range 250–850 nm. After the plasma is applied, the gold impregnation over the titania surface increases the photocatalytic activity.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号