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991.
四川盆地安岳气田是中国迄今为止发现的最大规模的海相碳酸盐岩气田,探明天然气地质储量1.03×1012 m3,其中震旦系灯影组占56.3%。目前灯影组勘探开发主要围绕灯影组四段台缘带展开,且台缘带单井产能明显高于台内地区。基于台缘带和台内地区天然气地球化学特征及气藏对比关系,结合成藏条件分析,探讨其成藏差异性。研究表明:(1)灯影组台缘带较台内地区天然气甲烷氢同位素明显偏重,对应寒武系源岩古水体介质盐度高于震旦系,反映由台缘带到台内地区震旦系烃源岩贡献比例的增加;(2)台缘带与台内地区储层在岩石类型、储集空间等方面一致,但台缘带储层内部溶蚀孔洞发育程度强于台内地区,主要受控于丘滩发育程度和表生岩溶作用强度;(3)台缘带和台内地区成藏组合存在差异,台缘带紧邻裂陷内烃源岩,储层侧向对接烃源岩,存在旁生侧储、上生下储等多种成藏组合,而台内地区距裂陷内烃源岩较远,需要通过沟通油、源的断裂输导油气,成藏组合单一;(4)震旦系-寒武系烃源岩贡献比例的不同和优质储层发育位置及组合类型的差异,是导致台缘带和台内地区产能差异巨大的主要原因。川西北蓬莱—剑阁地区是... 相似文献
992.
模拟催化裂化高温水热再生环境,采用X射线衍射、N2物理吸附、高分辨电子透射显微镜与NH3-程序升温热脱附等方法,研究了重金属元素钒(V)对催化剂活性组分水热超稳Y型分子筛(USY型分子筛)的破坏行为;在此基础上,研究了稀土氧化物氧化镧(La2O3)对重金属V的捕集作用。结果表明:当分子筛负载较高质量分数的V时,分子筛的晶体结构遭到严重破坏;与未负载V的催化剂相比,负载质量分数为0.5%的催化剂,转化率降低了16.3个百分点,目标产物(液化气和汽油)收率显著降低,副产物干气、焦炭收率大幅增加;向模型催化剂中添加La2O3可以提高催化剂的重金属V捕集能力,在V负载质量分数为0.6%的情况下,含有La2O3的模型催化剂的原料油转化率和目标产物收率大幅增加。 相似文献
993.
陆丰13东洼是珠江口盆地油气勘探的重点区域。结合区域构造背景,在精细解释高品质三维地震资料的基础上,对陆丰13东洼的洼陷结构和构造特征进行综合分析,并运用平衡剖面技术对洼陷的构造演化进行了恢复与研究,探讨了构造演化对圈闭形成与成藏的影响。研究结果表明: ①陆丰13东洼新生代构造演化可划分为早-中始新世断陷、晚始新世断坳转换、渐新世-第四纪区域热沉降坳陷等3个阶段,其中断陷阶段具有完整的断陷旋回,根据断陷活动的强弱可进一步划分为断陷初始期、断陷高峰期、断陷萎缩期,断陷初始期和断陷萎缩期储层较为发育,断陷高峰期烃源岩较为发育。②在多期次构造活动的影响下,陆丰13东洼新生代形成了多种类型的圈闭,包括披覆背斜圈闭、断背斜圈闭、断块圈闭、断鼻圈闭、构造-地层圈闭 (削截、超覆) 、构造-岩性圈闭。众多的圈闭类型表明研究区油气勘探潜力巨大,特别是断陷阶段与断坳转换阶段沉积的文昌组和恩平组均发育大量各类型圈闭,且邻近优质烃源岩,成藏条件优越,是陆丰13东洼油气勘探的重点层系;平面上,南部缓坡带发育圈闭类型及数量最多,其次是中央隆起带与低凸起,均是研究区油气勘探的重要区带。 相似文献
994.
Multiple functional and hard-to-quantify sensorial product attributes that can be satisfied by a large number of cosmetic ingredients are required in the design of cosmetics. To overcome this problem, a new optimization-based approach for expediting cosmetic formulation is presented. It exploits the use of a hierarchy of models in an iterative manner to refine the search for creating the highest-quality cosmetic product. First, a systematic procedure is proposed for optimization problem formulation, where the cosmetic formulation problem is defined, design variables are specified, and a set of models for sensorial perception and desired product properties are identified. Then, a solution strategy that involves iterative model adoption and two numerical techniques (i.e., generalized disjunctive programming reformulation and model substitution) is applied to improve the efficiency of solving the optimization problem and to find better solutions. The applicability of the proposed procedure and solution strategy is illustrated with a perfume formulation example. 相似文献
995.
Jiajia Yan Teng Zhang Haizheng Tao Hongbing Zhan Yuanzheng Yue 《Journal of the American Ceramic Society》2021,104(6):2560-2570
We study the structure, crystallization, and performances of the sealing glasses with the composition (mol.%) of 12Al2O3·8B2O3·40SiO2·40RO (R = Mg, Ca, Sr) for solid oxide fuel cells (SOFCs) before and after isothermal treatment at 700°C, which is within the operation temperature range (600-800°C) of SOFCs. The crystallization behavior has been investigated by differential scanning calorimetry and X-ray diffraction under both dynamic and isothermal conditions. The structural evolution is probed using the Raman and nuclear magnetic resonance spectroscopies. The performances of the sealing glasses are characterized in terms of the coefficient of thermal expansion, the crystallization-induced stress at glass–steel interface. We find that strong crystallization occurs at the operation temperature (700°C) far below the crystallization onset temperature measured by DSC. The structure origin of this anomalous crystallization is discussed in terms of structural heterogeneity of the three studied glasses. We determine the residual stress at the interface between the Ca-containing glass and the steel after isothermal treatment at 700°C for 48 h, but this stress does not lead to falling off the glass layer from the steel. This indicates that this glass is a good candidate to be applied in SOFCs. 相似文献
996.
Hang Luo Jian Wu Fei Teng Benlong Su Haohao Li Ange Lin Zhe Li Youshan Wang 《应用聚合物科学杂志》2021,138(20):50453
The friction behavior of cylinder seal greatly affects the dynamic position accuracy of the cylinder execution terminal under hydrothermal aging. So, the hydrothermal aging test, friction test, tensile and compression test, topography analysis and infrared spectroscopy analysis, and multiscale simulation were carried out for studying the effect of the hydrothermal aging on the friction performance of cylinder seal. It was found that when the aging temperature increases from 40 to 80°C, the dynamic friction forces of the cylinder seals increase by more than 15%; the friction force increases with the increasement of the initial mechanical stress. Aging makes rubber to be brittle and more cavities on the fracture surface and reduces the fractured activation energy of the nitrile rubber molecular chain. 相似文献
997.
Jing Lv Longhai Guo Chunjie Xie Weitong Xu Jun Ye Xiaoyu Li Teng Qiu Xinlin Tuo 《应用聚合物科学杂志》2021,138(44):51316
Being a new kind of nanomaterials, aromatic polyamide nanofibers (ANF) have been much highlighted in recent studies. We here demonstrate an isopropyl alcohol (IPA) accelerated chemical cleavage on poly (p-phenylene terephthalamide) chopped fibers, which provides an efficient preparation method of ANF. The comprehensive study on the processes accelerated by different alcohols revealed that the preparation time of ANF in the mixed medium of dimethyl sulfoxide (DMSO)-alcohol (20:1 in volume) was shorten to 45 min and 75 min for methanol (ethanol) and isopropanol, respectively. However, the nanofibers prepared in DMSO-IPA exhibited the minimum in axial and radial dimensions, providing the finest and most uniform diameter of 16 nm. The corresponding ANF films through vacuum assisted filtration also showed the highest tensile strength of 150 MPa, in comparison with those of the ANF films prepared using other alcohols, which were about 110 MPa. Furthermore, ANF/silicon hybrid films were prepared by the ionic ring-opening reaction followed by the alkoxysilane condensation and nanoparticle fabrication. By changing the organo functional groups in the alkoxysilane, the surface of the films were adjustable in a wide contact angle range from 56° (hydrophilic) to 150° (superhydrophobic), suggesting the amendable interfacial properties potential applicable to composite fabrication with most of the resin matrix. 相似文献
998.
999.
衰减直流(DDC)分量、高次谐波等干扰信号的存在,使得对电网畸变信号中基频分量的幅值、相位检测存在一定误差,其中DDC分量的时间常数通常超过45 ms,持续时间较长.为此,文中首先针对畸变信号中DDC分量提出一种半周期四点采样检测算法,缩短了DDC分量的检测响应时间.其次,针对同时含有DDC分量与高次谐波的畸变信号,提出将畸变信号进行半周期积分后,在dq坐标系下将上述DDC分量检测算法与高次谐波检测算法进行组合,在工频半周期中可同时滤除干扰信号的影响,准确检测到畸变信号中的基频分量.最后,搭建了MATLAB/Simulink半实物实时仿真模型,从检测精度、响应时间等方面验证了所提算法的有效性. 相似文献
1000.
小概率-高风险极端天气灾害事件的频发对电力系统的安全稳定运行提出了重大挑战.针对深度耦合的电-气综合能源系统,文中提出一种考虑极端天气下配电网线路故障概率信息的弹性导向分布鲁棒优化模型以提升其弹性能力.首先,融合极端条件下元件故障概率区间构造线路故障模糊集,在此基础上建立防御-攻击-防御3层框架下的配电网弹性提升优化问题.其次,构建以燃气机组出力为耦合变量的天然气系统运行可行性子问题.然后,提出一种内外双层循环算法求解上述问题:外层循环结合对偶理论和列与约束生成算法求解配电网优化问题;内层循环采用Benders分解算法对气网问题进行校验.最后,通过算例验证了所提模型及求解算法的有效性. 相似文献