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101.
渤海东部新构造运动活动带油气晚期快速成藏的证据 总被引:1,自引:0,他引:1
新构造运动控制了渤中坳陷油气成藏过程及分布。应用盆地模拟、油源对比、流体包裹体定年等方法和技术对黄河口凹陷烃源岩生烃演化史、BZ34断裂带油气来源和充注历史进行的研究认为:BZ34断裂带油气主要来自构造区周围沙河街组晚期快速熟化烃源岩,油气主充注期发生在新构造运动以来。BZ34断裂带油气为晚期快速成藏。蓬莱19-3油田晚期构造圈闭、各断块流体温度非均质性、流体包裹体均一温度高异常以及浅层气富集表明该油田油气也为晚期快速充注。通过对这两个典型油气藏成藏历史的综合分析,认为渤海东部新构造运动活动带油气均属于晚期快速成藏。 相似文献
102.
103.
综合利用地球化学、测井、地震等资料研究霸县凹陷烃源岩的生烃潜力、有机质类型、母质来源及沉积保存条件。根据烃源岩与原油的生物标志化合物参数特征进行油源对比,厘清各套烃源岩对油气成藏的贡献。研究结果表明,霸县凹陷发育沙四段、沙三段下亚段及中亚段、沙一段下亚段4套烃源岩,具有生排烃潜力大、有机质类型好的特点,且均已进入生烃门限。其中,沙四段和沙三段下亚段、中亚段烃源岩分布较广,沙一段下亚段烃源岩仅分布于研究区南部地区。生物标志化合物参数分析结果揭示,研究区4套烃源岩的有机质输入与沉积保存条件存在差异,沙四段和沙三段下亚段有机质供应相对于沙三段中亚段和沙一段下亚段充足,但是沉积保存条件却相对较差。通过油源对比发现,霸县凹陷的原油可以分为3类单源油及2类混源油,沙三段下亚段和中亚段烃源岩是现今已发现油藏的主力贡献烃源岩,沙四段烃源岩的有机质丰度较高、生烃潜力大,但已发现以沙四段烃源岩提供油源的油藏多呈近源零星分布于深层及潜山,表明霸县凹陷以沙四段烃源岩为油源的深层及潜山油藏应具有较大的勘探潜力。 相似文献
104.
Mitogen-activated protein kinases are a group of ubiquitously expressed kinase pathways that have been conserved from yeast through humans. They control a large number of critical cell functions. Identification of targets of those kinases is necessary to define signal transduction pathways that lead to cell responses. The application of a number of mass spectrometry-based techniques to the identification of phosphoproteins is reviewed. A new proteomic approach is described for the identification of the downstream targets of specific kinases that combines phosphorylation of cell lysates in in vitro kinase reactions by active recombinant kinase with protein separation by two-dimensional (2D) gel electrophoresis or SDS-PAGE and phosphoprotein identification by MALDI-TOF mass spectrometry or by phosphopeptide enrichment and tandem mass spectrometry. The results suggested that a combination of multiple approaches will be required to fully identify phosphoproteomes. 相似文献
105.
Michelliza S Abraham WM Jacocks HM Schuster T Baden DG 《Chembiochem : a European journal of chemical biology》2007,8(18):2233-2239
Brevetoxins are neurotoxic compounds produced by the dinoflagellate Karenia brevis. Extensive blooms induce neurotoxic shellfish poisoning (NSP) and asthma-like symptoms in humans. beta-naphthoyl-brevetoxin, the first semisynthetic brevetoxin antagonist, has been defined as the lead compound in the investigation of the mechanisms of bronchoconstriction induced by inhaled brevetoxins and relaxation or reversal of those effects by selected derivatives. In pursuit of more potent and effective brevetoxin antagonists, a series of beta-naphthoyl-brevetoxin analogues have been synthesized. Activities were determined by competitive displacement of tritiated brevetoxin-3 from rat brain synaptosomes and by lung resistance measurements in sheep. Additionally, preliminary computational structural studies have been performed. All analogues bound to rat brain synaptosomes with affinities similar to beta-naphthoyl-brevetoxin but exhibited very different responses in sheep. The biological evaluations along with computational studies suggest that the brevetoxin binding site in rat brain synaptosome might be different from the ones in lung tissue and both steric and electrostatic factors contribute to the efficacy of brevetoxin antagonism. 相似文献
106.
We present a robust and computationally efficient method for retrieving aerosol optical depth (AOD) from top-of-atmosphere ATSR-2 (Along-Track Scanning Radiometer) and AATSR (Advanced ATSR) reflectance data that is formulated to allow retrieval of the AOD from the 11 year archive of (A)ATSR data on the global scale. The approach uses a physical model of light scattering that requires no a priori information on the land surface. Computational efficiency is achieved by using precalculated lookup tables (LUTs) for the numerical inversion of a radiative-transfer model of the atmosphere. Estimates of AOD retrieved by the LUT approach are tested on AATSR data for a range of global land surfaces and are shown to be highly correlated with sunphotometer measurements of the AOD at 550 nm. (Pearson's correlation coefficient r(2) is 0.71.). 相似文献
107.
Buffering of high-pH (>12) steel slag leachate is documented across a small, natural calcareous wetland. The alkaline leachate is supersaturated with respect to calcite upstream of the wetland (Sl(calcite) values +2.3) and becomes less saturated with progress across the wetland, to Sl(calcite) values of +0.27 at the wetland outlet. Reduction in pH across the wetland (to around pH 8 at the wetland outlet) was observed to be more pronounced over summer months, possibly due to increased microbial activity, possibly further assisted by greater flow baffling by emergent vegetation. Calculated calcite precipitation rates downstream of the leachate source, estimated from hydrochemical data, flow, and surface area, were on the order of 0.4-15 g m(-2) day(-1), while direct measurements (using immersed limestone blocks) showed calcite precipitation values in the range 3-10 g m(-2) day(-1). Precipitation rate was highest in the pH range where the carbonate ion is a dominant constituent of sample alkalinity (pH 9.5-11) and at the locations where wetland biota became established downstream of the leachate emergence. These data provide valuable insights into the potential for using constructed wetlands for the passive treatment of high pH steel slag leachates. 相似文献
108.
A variety of techniques (secondary electron microscopy with energy dispersive X-ray analysis, time-of-flight--secondary ion mass spectrometry, and synchrotron X-ray fluorescence) were utilized to distinguish metal contamination occurring in hair arising from endogenous uptake from an individual exposed to a polluted environment, in this case a lead smelter. Evidence was sought for elements less affected by contamination and potentially indicative of biogenic activity. The unique combination of surface sensitivity, spatial resolution, and detection limits used here has provided new insight regarding hair analysis. Metals such as Ca, Fe, and Pb appeared to have little representative value of endogenous uptake and were mainly due to contamination. Cu and Zn, however, demonstrate behaviors worthy of further investigation into relating hair concentrations to endogenous function. 相似文献
109.
Detection of low-abundance protein phosphorylation by selective (18)o labeling and mass spectrometry
Reversible phosphorylation regulates the majority of intracellular networking and pathways. The study of this widely explored post-translational modification is usually challenged by low stoichiometric levels of modification. Many approaches have been developed to overcome this problem and to achieve rigorous characterization of protein phosphorylation. We describe a method for enhanced detection of low-abundance protein phosphorylation that uses selective introduction of (18)O label into phosphorylation sites with H(2)(18)O and mass spectrometric detection. The method was applied to introduce (18)O label into bacterially expressed Aurora A kinase phosphorylation sites and resulted in the representation of phosphorylated peptides as doublets or triplets according to the number of phosphate groups. A total of 28 phosphopeptides were observed by this method. 相似文献
110.
Narrow laser beams directed from aircraft may at times pass through the exhaust plume of the engines and potentially degrade some of the laser beam characteristics. This paper reports on controlled studies of laser beam deviation arising from propagation through turbulent hot gases, in a well-characterized laboratory burner, with conditions of relevance to aircraft engine exhaust plumes. The impact of the temperature, laser wavelength, and turbulence length scale on the beam deviation has been investigated. It was found that the laser beam displacement increases with the turbulent integral length scale. The effect of temperature on the laser beam angular deviation, σ, using two different laser wavelengths, namely 4.67 μm and 632.8 nm, was recorded. It was found that the beam deviation for both wavelengths may be semiempirically modeled using a single function of the form, σ=a(b+(1/T)(2))(-1), with two parameters only, a and b, where σ is in microradians and T is the temperature in °C. 相似文献