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1.
近年来在下扬子地区页岩气地质调查井所获取的地层岩心资料,揭示该地区下志留统风暴沉积较为发育。基于精细的岩心观察描述,详细分析了下扬子地区下志留统高家边组下段中上部风暴沉积的特征,并阐明了风暴作用对泥页岩的影响。研究表明:研究区风暴岩岩性偏细,以粉砂岩为主,石英含量较高,结构成熟度较低,具2种不同的粒度概率曲线;主要发育底部冲刷面、块状层理、平行层理、丘状交错层理、波纹交错层理、准同生变形构造等沉积构造;垂向上主要识别出4种风暴沉积序列,均具有从底到顶粒度变细的沉积特征,不同的沉积序列与风暴流能量的强弱有关。下扬子地区早志留世频繁的风暴活动与研究区的古地理背景和古气候条件具有内在联系。特大型风暴对浅海陆棚深水区的细粒泥质沉积物特征产生重要影响,包括降低有机质含量、减少单层厚度、破坏垂向连续性、改变原始沉积构造和侧向稳定性等,总体上降低了泥页岩的品质。因此,研究认为在页岩气的勘探和评价过程中应重视风暴因素对陆棚深水区原始泥质沉积物的影响。 相似文献
2.
《Advanced Powder Technology》2022,33(12):103879
Heat transfer within ceramic feedstock powders is still unclear, which impedes optimization of the thermal and mechanical properties of the thermal sprayed coatings. The microspheres (yttria-stabilized zirconia YSZ and lanthanum zirconate LZO) were prepared via the electro-spraying assisted phase inversion method (ESP). The thermal properties of the two ESP microspheres and a commercial hollow spherical powder (HOSP) were investigated by using theoretical, experimental, and simulation methods. Thermal conductivity of the single microsphere was estimated via a novel nest model that was derived from the Maxwell-Eucken 1 and the EMT model. Thermal conductivity of a single YSZ/LZO-ESP microsphere prepared at 1100–1200 °C was within 0.36–0.75 W/m K, which was ~ 20 % lower than that of a single YSZ-HOSP microsphere with a similar porosity. Heat flux simulation showed that high tortuosity around the multi-scaled voids of the ESP microsphere led to a more efficient decrease in thermal conductivity compared with total porosity. 相似文献
3.
《Journal of the European Ceramic Society》2021,41(14):6983-6990
Ternary 0.552Pb(Ni1/3Nb2/3)O3-xPbZrO3-(0.448-x)PbTiO3 (PNN-PZ-PT) ceramics near the triple point compositions were fabricated by an improved two-step sintering method. The triple point composition 0.552PNN-0.135PZ-0.313PT ceramic has outstanding piezoelectric performance with piezoelectric coefficient d33 = 1200 pC/N. Its easy fabrication and low cost make this piezoelectric material an excellent candidate for high sensitivity sensors and ultrasonic transducers. The evolution of domain structures for ceramics with composition near the triple point provides deeper insight into the mechanism of ultrahigh piezoelectric properties of PNN-PZ-PT ceramics. 相似文献
4.
新疆阿尔泰南缘北塔山组火山岩较为发育。本文对新疆阿尔泰南缘默色克奥依一带北塔山组火山岩进行地球化学分析和年代学研究。研究表明:U-Pb锆石年龄为(384.3±4.0Ma)Ma,为中泥盆世;该组火山岩属于钾质钙碱性系列,全碱(Na2O+K2O=2.07%-6.49%)和YiO2(0.24%-0.64%)含量较低,K2O含量(1.11%-4.04%)变化较大,稀土元素含量(∑REE)较低。稀土元素显示其轻稀土富集且分馏不明显;δEu值均大于1,为Eu富集型;δCe值均小于1,为Ce亏损型。该组火山岩微量元素P明显富集,K、Rb、Ba等大离子亲石元素(LILE)略富集,亏损Ta、Zr、Hf、Ti等高场强元素(HISF)。结合前人研究,本文认为默色克奥依一带北塔山组火山岩形成于岛弧及与俯冲过程有关的活动大陆边缘造山带环境,为泥盆纪古大洋俯冲消减过程中,俯冲板片脱水产生的流体交代上覆地幔楔部分熔融的产物。 相似文献
5.
Improvements in information and communications technologies (ICTs) have facilitated the inclusion of the sharing economy (SE) in societies more than ever. In the aftermath of recent disasters, the SE played significant roles to help the affected people and support official responders. However, the literature has not effectively explored these roles, and thus, no framework can support the systematic inclusion of the SE in disasters management. This paper aims to address the gap through a two-stage exploratory research approach. First, we conduct a systematic literature review to identify the extent to which the SE is taken into consideration in disasters. After that, we investigate the role of three Iranian SE-based companies that were involved in the 2019 Iran floods response. We collect empirical data by conducting semi-structured interviews and reviewing official reports.Our findings indicate that very few studies discuss the different roles of the SE in disasters, although SE companies have often provided effective solutions to address critical post-disaster logistics challenges. Four research propositions are presented to describe emerging roles for SE companies. The contribution of our study is twofold. First, our research identifies the different roles that the SE could play in disasters and therefore, brings a new perspective to the literature. Second, the study suggests opportunities for collaboration and partnership models from the point of origin to delivery that can support coordination and logistics in disasters. 相似文献
6.
《全球能源互联网(英文)》2020,3(4):385-397
Africa is embracing new opportunities featured with industrialization, urbanization and regionalization. Based on co-development of ‘Electricity, Mining, Metallurgy, Industry and Trade’ and grids interconnection proposed by Global Energy Interconnection Development and Cooperation Organization (GEIDCO), the high-quality hydropower resource of the Congo River can be exploited in large scale under the wide-range interconnected framework of African Energy Interconnection (AEI), forging a new engine for Africa economy. The transmission distance of the Congo River hydropower reaches 6,000 km at its farthest end in North Africa, which brings forth challenges to economics of proposed projects. Under this novel continental energy interconnection scheme in Africa, economics of those projects have not yet been in detail studied. This paper has implemented China’s mature engineering experiences and analytical tools of UHVDC project planning into the AEI structure, through exploring the economic behavior of ultra-long distance UHVDC projects in the scope of conductor selection in the Congo River hydropower transmission for the first time, and has provided concerned parties with a technical and analytical results of their economics comparison. This paper has chosen the D.R. Congo - Guinea ±800 kV UHVDC project as a typical example. Its preliminary system planning is introduced and three types of conductor are selected for scheme comparison. Later in this paper, the transmission loss, total investment and equivalent annual cost of the project have been calculated and analyzed. In the final part, sensitivity analysis results of the annual cost to utilization hours, transmission loss, loss tariff and construction cost has been provided 相似文献
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8.
针对网络扫描工具在进行扫描时面临的溯源问题,提出了一种匿名网络扫描系统。首先将匿名系统与网络扫描工具结合以实现匿名扫描;然后在现有匿名系统的基础上实现了该系统的本地私有化;接着通过流量分析发现,Nmap的多进程扫描因为代理链的原因会变成单进程扫描而导致其扫描扫描性能较低;最后提出了一种基于多Namp进程并发的性能优化方案,将总体扫描任务分割为多个扫描任务,并分配给多个单独的Nmap进程并行运行。实验结果表明,该性能优化方案的扫描时延接近正常扫描情况下的时延,达到了提高匿名扫描系统性能的目的。因此,该优化后的网络匿名扫描系统在阻碍溯源的同时提升了扫描效率。 相似文献
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10.
目的 研究发酵乳杆菌(Lactobacillus fermentum) HCS08-005耐逆性及对体外细胞的免疫调节作用。方法 考察发酵乳杆菌HCS08-005的耐酸耐胆盐能力,并应用发酵乳杆菌HCS08-005细胞裂解物,处理小鼠单核巨噬细胞RAW264.7和小鼠脾脏细胞,用酶联免疫吸附测定试剂盒检测各类炎症因子包括肿瘤坏死因子-α (tumor necrosis factor-α,TNF-α)、白细胞介素-2 (inter-leukin-2,IL-2)、白细胞介素-12 (inter-leukin-12,IL-12)、γ干扰素(interferon-γ,IFN-γ)的表达水平。结果 显示发酵乳杆菌HCS08-005有较好的耐逆性,能够耐受酸和胆盐环境到达肠道发挥作用。不同浓度的发酵乳杆菌HCS08-005细胞裂解物对小鼠脾脏细胞和巨噬细胞分泌炎症因子均有极显著影响(P<0.01),在质量浓度为100 μg/g时,IL-2分泌量为421.49 pg/g,TNF-α分泌量为161.23 pg/g,IFN-γ分泌量为846.14 pg/g,IL-12分泌量为12.88 pg/g,因子水平极显著提高(P<0.01)。结论 在体外细胞试验中,发酵乳杆菌HCS08-005有较好的耐逆性,对体外细胞有免疫调节作用。 相似文献