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1.
企业试图完成数字化转型,这是在竞争中谋求发展的必经之路。文章率先进行数字化转型特征、策略的概念分析,而后总结以此为背景的能力模型、企业管理能力与技术能力,最终以某公司案例完成体系构建与应用的阐述。 相似文献
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《Journal of Great Lakes research》2022,48(3):659-668
Previous studies reported coastal trapped waves (CTWs) in the Caspian Sea (CS). This study deals with the generation mechanisms, the temporal and spatial variability of CTWs in this area, and their transformations during propagation from the origin to the destination using recent measurements and high-resolution numerical simulations. CTWs are observed at all stations with periods of 2–6 days after northerly storms. The Absheron Peninsula, old Sefidrud delta, and Nur coasts were identified as the CTWs prone regions. The generation of CTWs in these locations was confirmed using numerical experiments. The propagation away from the generating location of CTWs was analyzed using a representative real wind storm. In the west part of the CS, the generation mechanism of CTWs is mainly similar to the barotropic Kelvin waves; in contrast, it is similar to the continental shelf waves in the southern shelves. The results can be used to study the contribution of generated CTWs to the transport of sediment and biological materials in all large lakes. 相似文献
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四川盆地中三叠统雷口坡组天然气勘探近年来取得重要突破后继而成为业内关注的热点,但对气源的认识存在较大的分歧。基于天然气地球化学特征开展的成因鉴别和气源对比研究表明,雷口坡组天然气既有主要来自下伏上二叠统龙潭组/吴家坪组烃源岩(磨溪雷一段气藏),断裂下盘须一段烃源岩有一定贡献(中坝雷三段气藏)或供烃条件(川西雷四段气藏),也有主要来自须家河组烃源岩,雷口坡组自身烃源岩有一定贡献(元坝和龙岗雷四段气藏)。雷口坡组气藏具有3种不同的源储组合,其天然气勘探方向具有差异。上二叠统龙潭组烃源岩作为主力烃源岩构成下生上储型,切穿龙潭组至雷口坡组的深断裂周缘的正向构造是寻找雷口坡组规模性气藏的最有利区。上三叠统须家河组底部烃源岩和雷口坡组顶部储层可以构成旁生侧储型,岩溶残丘或岩溶斜坡局部构造高点是这类组合较有利的发育部位。雷口坡组自身构成自生自储型,这类组合往往作为辅助参与气藏形成。 相似文献
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In this work, the effects of support surface pore structures(including surface pore size, surface pore density and surface porosity) on the performance of thin film composite(TFC) gas separation membrane over a wide pressure range(from 0.3 to 2.0 MPa) were studied. To fulfill it, the polysulfone(PSf) supports with different surface pore structures were prepared. Two kinds of wide-accepted polymeric membrane materials, i.e., polyvinylamine(PVAm) and Pebax 1657 copolymer, were used as skin layer materials. We pointed out for the first time that the support surface average pore size and pore density could affect the chain mobility of polymer of skin layer at the support surface pore entrance, then, can affect the TFC membrane performance. Besides, we also discussed the effects of support on the TFC membrane performance when the feed pressure changes for the first time. This work can provide guidance for choosing a suitable support for TFC gas separation membrane. 相似文献
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《Egyptian Journal of Petroleum》2019,28(4):377-382
Four hydrocarbon-base gasolines (BG) were formulated from the local refinery streams; isomerate, reformate, and light naphtha. The formulations were enriched in reformate. Each of these BG formulations was blended with 10 vol% of anhydrous ethanol. From ASTM-D86 distillation data, eight distillation curves were constructed and the trend line equations of these distillation curves were developed. Also, the area under each distillation curve (AUDC) was calculated through calculus definite integration technique. Subsequently, the area due to azeotrope formation (ADAF) for each BG-ethanol blend was estimated. In this paper, the influence of increasing reformate proportions on the created positive azeotrope, was studied. Also the influence of increasing reformate proportions on vapor pressure, Temperature for the vapor-liquid ratio of 20, T50 and octane number was studied. The results show that the R2 values of the distillation curve equations prove the reliability of the fits. Also, increasing reformate proportion in the fuel blend improves the octane number while increasing reformate proportion decreases the volatility of the fuel formulation. 相似文献
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孙守华 《石油与天然气化工》2018,47(1):26-29, 40
针对某石化公司FCC汽油选择性加氢装置在运行过程中陆续出现产品辛烷值低的问题进行分析,认为装置产品辛烷值低的原因包括:(1)选择性加氢催化剂选择性差;(2)碳六烯烃饱和严重;(3)异戊烯醚化率低。通过优化选择性加氢反应条件、提高轻汽油抽出率及醚化反应温度等措施,装置选择性加氢产物、汽油产品及醚化汽油的研究法辛烷值分别提高了1.5个单位、0.5个单位及0.05个单位。 相似文献
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山茶籽油是一种纯天然高级食用植物油,富含油酸、亚油酸等功能性成分,具有抗衰老、提高免疫力、预防肥胖等作用。近年山茶籽油因其具有极高的营养价值,备受人们关注。然而,一些不法商贩为了谋取利益,在山茶籽油中掺入低价食用油欺骗消费者,扰乱其市场秩序。因此,为了保障消费者的合法权益和山茶籽油的良性发展,研究者必须采用相应的检测方法鉴别其真实属性。本文综述各类检测方法在鉴别山茶籽油真实属性中的应用现状,如理化分析法、光谱法、色谱法、电子鼻技术等,并根据当前鉴别方法存在的缺陷,对未来分析山茶籽油真实属性的研究趋势进行展望,旨在为食用植物油的掺杂掺假检测提供理论参考。 相似文献