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51.
Despite the detrimental effects of divided attention at encoding on later memory performance, results described in the literature do not unequivocally specify which processes are interrupted during encoding by participants' occupation with a concurrent task. Using a processing analysis framework where the encoding process is viewed as a multiphase mental activity, the current research investigated this issue using a new differential temporal interference paradigm where the study phase of single words was interrupted at different temporal segments. In two experiments, we used performance on both memory and online choice reaction time tasks to assess whether such differential interference would produce different degrees of reduction in participants' later memory performance, as well as changes in the attentional resources required to execute each of the encoding phases. Measures of memory and concurrent task performance in the two experiments converged on similar patterns, showing that all phases of encoding are affected by the concurrent task. However, the initial encoding phase, which is tentatively associated with the initial registration of information, seems especially vulnerable to interference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
根据地区电网的实际管理模式,提出了基于变电站九区调节的地区电网分层无功优化方法:将地区电网分成次输电电网和配电网。先对次输电网进行无功优化时,将配电网等效为负荷,此时控制变量少,采用传统算法可以快速求解。在此基础上,再采用九区图方法调整配电网的无功电压,进行迭代,逐层进行无功优化直到问题收敛。实际算例表明,这种方法优化了地区电网的运行,提高了无功优化的计算速度,并且更符合实际电网的管理模式,为地区电网无功电压调节提供了有益参考。  相似文献   
53.
溜井运输方案在国内外的冶金、煤炭、建材等行业已被广泛采用,并在设计、运行方面取得了较为成功的经验,在国内龙滩、锦屏等水电工程的料场开采运输中也得到了成功的运用。托巴水电工程古松料场地形陡峻,开采边坡高约300m,开采运输道路修建困难,且距坝区较近,对坝区施工干扰较大。通过对"公路运输方案、溜井+公路运输方案、溜井+胶带机运输方案"3个开采运输方案进行比较,初步推荐采用"溜井+公路运输方案",以有效解决料场开采运输存在的问题。  相似文献   
54.
针对目前在多孔河岸式溢洪道上采用窄缝挑坎消能工,都是沿闸墩用长墩隔开,至出口段将墩体升高加厚、急剧收缩成窄缝的结构形式。全程隔墩混凝土用量大,加上强大侧向水压力荷载等影响到工程投资、结构安全与泄洪运行管理问题。该设计提出省去泄槽中部的长隔墩,只在溢洪道出口连续挑坎下部加入“卧底式窄缝”,借以实现继续应用收缩式消能工。经模型试验表明:通过“分段连续坎”与“窄缝”的差动作用,出射水舌抛射呈十、廿、卅字形,加大入水面积和碰撞机率,消能效果良好,并方便人为控制水舌落点。在水电工程中有扩大应用潜力。  相似文献   
55.
真空灭弧室的一次封排工艺   总被引:1,自引:0,他引:1  
一次封排工艺是生产真空灭弧室的先进工艺,排气,封口同时进行一次完成。本文介绍了一次封排工艺的特点,及一次封排工艺的几点关键问题。  相似文献   
56.
Digital dermatitis is a serious problem in dairy production in many countries. In many settings, it is important to evaluate the digital dermatitis status of individual cows or an entire dairy herd. Such an evaluation has traditionally been done in a hoof trimming chute. An evaluation in the milking parlor can take place without disturbing the cows to a large extent, it can be done using less labor compared with an evaluation in a hoof trimming chute, and is cheaper than using a chute. The objective was to evaluate the sensitivity and specificity of a rapid screening method for digital dermatitis in the milking parlor, without using any specialized tools and taking approximately 15 s/cow. All lactating cows in 3 commercial Danish dairy herds were included. Cows were first scored for the presence of digital dermatitis during milking and the next day all cows were scored during hoof trimming. A 6-point nominal scoring system based on a visual inspection of the digital dermatitis lesions was used. For the analysis, the scores were dichotomized (digital dermatitis positive or digital dermatitis negative). Additionally, lesions were classified as small (diameter ≤ 2 cm) or large (diameter >2 cm). Sensitivity and specificity were calculated using observations from the hoof trimming chute as the “gold standard” and observations during milking as the diagnostic test. Relatively large variation was found between herds with an overall sensitivity of 0.65 (95% confidence interval: 0.59 to 0.72) and a specificity of 0.84 (0.81 to 0.87). The sensitivity increased to 0.69 (0.62 to 0.76), when only large lesions were assessed. The method has several advantages compared with evaluation in a chute and may be a useful tool in the daily hoof health management in dairy herds.  相似文献   
57.
Near-infrared (NIR) reflectance spectroscopy was evaluated as a rapid and environmentally benign technique for the simultaneous determination of macronutrients and energy in commercially available, packaged meals. Reflectance spectra (400–2498 nm) of homogenized meals were obtained with a dispersive NIR spectrometer. Protein and moisture were measured by AOAC reference methods, total fat by a semi-automated acid hydrolysis, solvent extraction, gravimetric method and total carbohydrate calculated. Energy was calculated using Atwater factors. Using multivariate analysis software, PLS models (n = 113–115 products) were developed to relate NIR spectra of homogenized meals to the corresponding reference values. The models predicted components and energy in validation samples (n = 37–38 products), overall, with r2 of above 0.96. Ratios of deviation to performance were between 3.6 and 6.6, and indicated adequacy of the models for screening, quality control, or process control. Performance of the models varied substantially when used to predict sub-groups of meals within the validation set.  相似文献   
58.
大花水水电站碾压混凝土拱坝快速施工技术   总被引:1,自引:1,他引:0  
大花水水电站拦河大坝为碾压混凝土双曲拱坝,最大坝高134.50 m。采用快速施工技术,创造了国内碾压混凝土连续浇筑上升33.5 m的记录。重点介绍了高速胶带机水平运输技术、缓降溜管垂直运输技术以及碾压混凝土仓面工艺。  相似文献   
59.
本文从历史和村庄生活的两重维度,分别从当家权的实施者、当家权的内容、当家权与家庭形式,对当家权进行三重分析,以便理解其内在逻辑。当家权的实施者中,老人和妇女当家的逻辑是不同的,老人当家的逻辑是大家庭的理想和责任义务,而妇女当家的逻辑却更多的是小家庭的利益,从老人当家到妇女当家,其中的发生逻辑要在整个社会形势中来理解。关于当家权的内容,老人当家要服务于大家庭的理想,所进行的是家庭内部的分工协调,具有长远预期和延续性,妇女当家却更多的是服务于小家庭的利益,也可以说,老人是在当大家庭的家,而妇女在当钱的家。当家权与家庭形式关系密切,与老人当家相符的家庭形式是大家庭,妇女当家使得老人因为生存策略的考虑主动分家,家庭日益核心化,而打工经济形势下出现"未分家式的分家",这是综合了老人大家庭理想和妇女当家现实的家庭新形式。  相似文献   
60.
A surge of research has been conducted to examine memory editing mechanisms that help distinguish accurate from inaccurate memories. In the present experiment, the authors examined the ability of participants to use novelty detection, recollection rejection, and plausibility judgments to reject lures presented on a recognition memory test. Participants studied a list of word pairs that were arranged in a category relationship (both words from the same category) or an unrelated relationship (both words from different categories) under full or divided attention. At test, participants were given a yes/no recognition test in which they were to respond after seeing the test items for 400 ms or 2,800 ms. Some of the test items were rearranged word pairs that were consistent with the study relationship, whereas others were inconsistent with the study relationship. The results demonstrate that the participants required full attention at study to use novelty detection, recollection rejection, and plausibility judgments to reject lures. Moreover, the results indicate that a long response deadline at test was needed for participants to use both recollection rejection and plausibility judgments to reject lures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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