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41.
42.
M.J. Pearson E. Grosjean C.S. Nelson S.L. Nyman G.A. Logan 《Journal of Petroleum Geology》2010,33(3):205-219
Trapped organic compounds (lipids) have been analysed in tubular carbonate concretions and their host sediments in Miocene deep water mudrocks from coastal outcrops in East Coast Basin and Taranaki Basin of North Island, New Zealand. The concretions, including calcitic, dolomitic and mixed mineralogies, have varied morphologies in many cases suggestive of conduits or pipes that channelled the escape of subsurface fluids and/or hydrocarbon gases. The extracted lipids include water column and/or diagenetically-derived alkanes, fatty acids and alcohols as well as specific marker compounds (including archaeal pentamethylicosane (PMI) and archaeol) associated with subsurface anaerobic oxidation of upwardly seeping methane gas (AOM). Strong carbon-13 isotopic depletions (δ13C –75 to –120‰) measured for PMI, archaeol and other AOM-specific marker compounds on three concretion samples support involvement of AOM in generating bicarbonate-rich fluid that was at least partly responsible for cementing the pipe-like concretions and central conduits. Other morphological types appear not to be AOM-related. Sterane and n-alkane parameters indicate low thermal maturity of the extracted organic matter. The molecular and compound specific isotopic organic geochemical evidence that some tubular concretions functioned as methane conduits thus supports an assertion that the tubular concretions represent ‘fossilised’ parts of the subsurface plumbing of biogenic or thermogenic hydrocarbon-fed cold seep systems. 相似文献
43.
利用铌酸锂晶体为压电换能器,熔石英为声光互作用介质,研制出调制速度为32MHz、工作频率为180MHz、渡越时间为15ns、用于RGB彩色合成中的的声光调制器,文中主要讨论和分析了Q参数与调制器中心工作频率、换能器长度的关系;讨论了R参数对衍射光束形状的影响及与衍射效率的关系,还讨论并确定了换能器最佳尺寸,经测试,高速率声光调制器衍射效率为47%,并测试了调制速度。 相似文献
44.
Interaction of ozone and organic matter in coagulation with inorganic polymer flocculant-PACl: Role of organic components 总被引:2,自引:0,他引:2
In this study, two model waters were used to evaluate the ozone effect on aquatic organic matter (AOM) removal by coagulation with inorganic polymer flocculant (IPF)-polyaluminum chloride (PACl). Flocs formation during coagulation processes were detected by using PDA (Photometric Dispersion Analyzer). Apparent molecular weight distribution (AMWD) and resin fractionation (RF) were also performed to characterize the change of AOM as a result of pre-ozonation. The experimental results show that the dosage of O3, characteristics and composition of AOM are the most important factors on the behavior of coagulation. Great differences have been found between the two model waters. Coagulation in model water 1 (MW1) (composed of humic acids) is impaired markedly by pre-ozonation, as more DOC (Dissolved Organic Carbon) is produced with increasing O3 dosage. Floc formation, as exhibited from decreasing of the slopes of FI (Flocculation Index), is retarded gradually during coagulation process. Although residual turbidity is reduced with 1.15 mg/L O3, removals of DOC and UV254 all decreased. As for model water 2 (MW2) (composed of salicylic acid), FI is retarded also, but turbidity and DOC removals of coagulation after pre-ozonation are improved to a certain extent. Coagulation performance judged from removal of DOC is improved distinctly by pre-ozonation. Fractionation results show that molecular weight of organic matter (OM) of MW1 is converted from higher to lower; and OM becomes from more hydrophobic to more hydrophilic, which might be one of the mechanisms involved in the impairment of ozonation on coagulation effect. OM in MW2 is oxidized and mineralized to a greater extent, thus its impairment on coagulation is released. Finally, according to water properties, some proposed applications were provided for application of ozone in water treatment process. 相似文献
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用声光调制的方法将激光二极管 (LD)抽运Nd∶YVO4 KTP激光进行光强调制 ,频率达 15MHz以上 ,衍射效率达 4 0 %~ 6 0 % ,满足了激光精密测量和新型激光彩色电视的技术要求 ,有很好的应用前景 相似文献
47.
Giovanni Monteleone Francesco Pallone Carmine Stolfi 《International journal of molecular sciences》2012,13(9):11071-11084
Chronic inflammation characterizing patients with inflammatory bowel disease (IBD) represents a major risk factor for the development of colorectal cancer. Mechanisms underlying this neoplastic transformation are not fully understood though studies in experimental models of colon carcinogenesis suggest that inflammatory cell-derived cytokines either directly or indirectly stimulate the uncontrolled growth of cancer cells. Nevertheless, under specific inflammatory conditions, immune cells can boost an anti-tumor immune response with the down-stream effect of eliminating dysplastic and cancerous cells. This review outlines the beneficial and detrimental role of inflammation in colon carcinogenesis. 相似文献
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49.
普通透射光镜观察结果表明,珠三坳陷早第三纪文昌组和恩平组的湖相暗色泥岩中都含有丰富的无定形有机质。文昌组的无定形有机质中含有盘星藻碎屑,属淡水浮游植物质的无定形有机质。透射电镜揭示,思平组泥岩中被透射光镜确定为无定形有机质的微屑实为煤质体(陆源植屑)。因此,文昌组和思平组的有机质类型反映了完全不同的古湖泊学特征。文昌组的无定形有机质反映了古湖泊表层水的高生产力和湖底水体的贫氧环镜。思平组的陆源植屑堆积与保存是古湖泊退缩消亡期的产物。 相似文献
50.
Ted?A.?Russin Frederick?R.?van de?VoortEmail author Jacqueline?Sedman 《Journal of the American Oil Chemists' Society》2004,81(2):111-116
Disposable polytetrafluoroethylene (PTFE) polymer IR (PIR) cards were used as substrates to rapidly oxidize edible oils and
simultaneously monitor the extent of oxidation by FTIR spectroscopy. Four edible oils were oxidized on PIR cards and in bulk
at moderate temperature (58°C), and real-time oxidation plots were obtained by measuring changes in the IR hydroperoxide (ROOH)
absorbance as a function of time. The relationship between the ROOH absorbance and PV was developed using a reference method
to define absorbances corresponding to PV end points of 100 and 200 meq ROOH/kg for the oils oxidized in bulk and on cards,
respectively. The real-time oxidation plots obtained for the oils oxidized in bulk and on cards were similar in appearance,
but the oils on the cards reached the PV end point 20 times faster than the oils oxidized in bulk. The results indicate that
the use of disposable PIR cards coupled with moderate heating and aeration provides a simple, practical, and rapid means for
monitoring oxidation and determining the oxidative stability of edible oils at a normal storage temperature. 相似文献