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1.
A NEW OIL SEEPAGE IN THE OMAN MOUNTAINS AND ITS GEOLOGICAL,GEOCHEMICAL AND PETROLEUM SYSTEMS CONTEXT
Mohammed Al Kindi Mohammed Al-Ghammari Alan Heward Paul Taylor George Siavalas 《Journal of Petroleum Geology》2022,45(1):5-28
A minor natural oil seepage is described from an unlikely setting in the Oman Mountains. The host rocks are fractured pelagic limestones of the lower member of the Triassic – Lower Jurassic Matbat Formation of the Hamrat Duru Group in the lower part of the allochthonous Hawasina Complex. This paper summarises Oman's established oil families and documents previously recorded oil seepages as context for describing the new seepage, its geochemistry, and possible source rock. The seep oil is different to those known from Oman's oil fields and probably derived from a poor quality, Mesozoic clastic source rock containing a mix of terrigenous and marine organic matter. The most likely source appears to be the Toarcian turbiditic upper member of the Matbat Formation, equivalent to the clastic Mafraq Formation of the Arabian Platform. The occurrence of source rocks in the allochthonous sediments of the NeoTethyan Hawasina Basin has been suspected previously, though their commercial significance remains to be established. 相似文献
2.
利用水力空化过程产生局部的高温、高压、高射流以及强大的剪切力等极端化学物理条件改质处理沙特重质原油,试验结果表明:沙特重质原油经过水力空化改质后粘度由13.61降低至7.22mm2/s,残碳由7.16%降低至6.48%,实沸点蒸馏后减压渣油降低1个百分点。进一步采用APPI FT-IR MS、XRD、FT-IR、SEM和粒度分布等技术研究了水力空化改质对沙重原油分子组成,沥青质团聚体微晶结构、沥青质胶束粒径分布、沥青质官能团、沥青质形貌等方面的影响,从分子角度阐述空化改质重油的机理。研究结果表明:水力空化改质后沙重原油分子量分布、芳烃类化合物缔合作用变小;沥青质对低DBE化合物吸附性能降低;沥青质团聚体微晶结构更加松散;沥青质胶束粒度分布降低;沥青质分子相互团聚作用力减弱。进一步考察了水力空化改质前后减压渣油延迟焦化性能,改质处理后焦炭产率降低1.85个百分点,液体收率和气体产率分别增加1.52和0.33个百分点,水力空化改质对沥青质性质、结构特点的改善能够有效的提高其加工性能。 相似文献
3.
《International Journal of Hydrogen Energy》2022,47(57):24107-24118
Vehicle fires in the tunnel are a great threat to the safe operation of the tunnel. Due to the rapid development of the hydrogen economy, the fire due to the hydrogen leakage could not be avoided and may bring great damage to the passengers and infrastructure. Due to the large difference between pool fires of traditional fossil-fueled and jet fires of hydrogen-powered vehicles, it is in doubt whether the existing longitudinal ventilation design could still be effective for the safety issue of hydrogen powered vehicles. To solve this problem, it is necessary to compare temperature characteristics of hydrogen-powered and traditional vehicle fires with and without longitudinal ventilations. In present work, we conducted a numerical investigation to discuss the different temperature distributions of traditional and hydrogen-fueled vehicle fires. Results indicate that the high temperature zone of the pool fire only exists above the ceiling of the vehicle. For hydrogen-powered vehicle fire, the high-speed hydrogen jet with the strong inertial force could push the hot smoke flows back to the ground. The ceiling temperature of hydrogen-powered vehicle fire is larger since hydrogen-powered vehicle has a larger heat release rate and the fire hazard of jet fires bring more danger compared with the pool fire. Although the temperature stratification is also obvious for the hydrogen-powered vehicle fire, the air temperature in the lower region could be heated and still high enough to bring a great damage to the passengers’ lives. This is quite different with the traditional pool fire. In addition, the critical ventilation velocity is also discussed. The theoretical equation could well predicted the critical ventilation velocity of traditional vehicle fires. For hydrogen-powered vehicle fires, the critical ventilation velocity could reach up to 6 m/s. The theoretical equation could not well predict the critical ventilation velocity of hydrogen-powered vehicle fires due to exist of hydrogen jet fires. 相似文献
4.
Wen-Sen He Jiaxin Rui Qingzhi Wang Zhen-Yu Chen 《European Journal of Lipid Science and Technology》2021,123(7):2000398
Piceatannol has shown to be a strong antioxidant in vivo, however, its ability to suppress lipid oxidation in foods has not been examined. The present study is to examine the antioxidant effect of piceatannol on heated canola oil compared with that of butylated hydroxytoluene (BHT). The oxidation of canola oil is conducted at 60, 90, 120, and 150 °C by monitoring the depletion of oxygen, the decrease in unsaturated fatty acids, and the changes of primary and secondary oxidation products. Results demonstrated that piceatannol can suppress lipid oxidation of canola oil in a dose-dependent manner with its effect being more effective than BHT. Practical Applications: Lipid oxidation is a major factor in the deterioration of food quality. Synthetic antioxidants, such as BHT and butylated hydroxyanisole, are used to inhibit oxidation in foods, but their safety has been always concerned. Piceatannol has exhibited a strong antioxidant activity to attenuate lipid oxidation and it should be further explored for use as a natural antioxidant in foods. 相似文献
5.
Karolina Storesund Francine Amon Anne Steen‐Hansen Shayesteh Haghighatpanah Ida Larsson 《火与材料》2021,45(1):181-190
The aim of this exploratory study has been to investigate the fire properties and environmental aspects of different upholstery material combinations, mainly for domestic applications. An analysis of the sustainability and circularity of selected textiles, along with lifecycle assessment, is used to qualitatively evaluate materials from an environmental perspective. The cone calorimeter was the primary tool used to screen 20 different material combinations from a fire performance perspective. It was found that textile covers of conventional fibres such as wool, cotton and polyester, can be improved by blending them with fire resistant speciality fibres. A new three‐dimensional web structure has been examined as an alternative padding material, showing preliminary promising fire properties with regard to ignition time, heat release rates and smoke production. 相似文献
6.
以橄榄油为原料,经臭氧氧化制备臭氧化橄榄油。利用核磁共振(NMR)采集碳谱数据,积分碳谱特征峰,计算橄榄油被氧化成分的相对含量。结果表明:臭氧化橄榄油与橄榄油碳谱有明显的区别,臭氧化橄榄油在δ103.1处出现新峰,对应δ130.1处的峰高减弱,这是由于橄榄油中的不饱和双键被氧化。采用该方法测得5个臭氧化油中活性成分含量分别为21.46%、21.03%、21.31%、18.71%和24.42%。采用核磁共振波谱法测定臭氧化橄榄油的活性成分含量具有操作简单,不需要预处理,结果可靠的优点。 相似文献
7.
为了建立一种准确性高、成本低的植物油中苯并(a)芘测定的样品前处理方法,基于GB 5009.7—2016以自制氧化铝柱为固相萃取柱,采用单因素试验对称样量、洗脱剂量、洗脱流速、吸附剂存放时间、吸附剂量这5个影响植物油中苯并(a)芘洗脱的因素进行研究,优化前处理条件,并对测定方法进行考察。结果表明:优化的前处理条件为称样量0.100 0 g、洗脱剂量120 mL、吸附剂(氧化铝)量22 g、洗脱流速1滴/2 s、吸附剂存放时间少于12周;方法检出限为0.2 μg/L,样品加标回收率为94.23%~100.00%,RSD为1.20%~7.36%;同一样品测定结果与SGS测定值接近,相对平均偏差为2.36%~3.50%。说明本试验方法测定结果准确,可应用于油脂企业植物油中痕量苯并(a)芘的测定。 相似文献
8.
Mauro Zammarano John R. Shields Isaac Leventon Ickchan Kim Shonali Nazare Andre Thompson Rick D. Davis Artur Chernovsky Matthew Bundy 《火与材料》2021,45(1):114-126
Herein, we describe a reduced‐scale test (“Cube” test), measuring the fire performance of specimens including a fire barrier (FB) and a flammable core material, which acts as the main fuel load. The specimen is intended to reproduce a cross‐section of a composite product where heat/mass transfer occurs primarily in a direction perpendicular to the FB. The Cube test procedure and benefits are discussed in this work by adopting residential upholstery furniture as an exemplary study. One flexible polyurethane foam, one polypropylene cover fabric, and 10 commercially available FBs were selected. They were used to compare the fire performance of FBs, measured in terms of peak of heat release rate, in the ASTM E1474‐14 standard test and the newly developed Cube test. Edge effects severely affected the performance of FBs in the ASTM E1474‐14 standard test but not in the Cube test. Furthermore, appropriate test conditions were determined in the Cube test to measure the so‐called “wetting point,” that is, the time and value of heat release rate measured when flammable liquid products were first observed on the bottom of the specimen. The relevance of the “wetting point” in terms of full‐scale fire performance and failure mechanism of FBs is discussed. 相似文献
9.
Callistus Nonso Ude Dominic Okechukwu Onukwuli Jonah Chukwudi Umeuzuegbu Chinemelum Chukwujekwu Chukwuka 《化学工程与技术》2021,44(1):65-76
The heterogeneous catalysis of transesterification of gmelina seed oil to biodiesel is evaluated. The oil was extracted from the seeds with n‐hexane by solvent extraction and characterized to determine its physiochemical properties. Response surface methodology was applied to optimize the effect of process variables on the biodiesel yield. The base‐activated clay catalyst performed as montmorillonite clay with the characteristic property of a Brønsted acid. It has an improved surface area after activation that enhanced its catalytic activity on transesterification reaction. Under optimal conditions, the biodiesel yield was 70.1 %, thus demonstrating that the model predicted well the biodiesel production. 相似文献
10.
为探究某加氢装置高压换热器管束腐蚀泄漏原因,利用Aspen Plus工艺模拟软件计算了冷低压分离器油相(简称冷低分油)中水质量分数分别为1%,2%,3%时,冷低分油系统的露点温度、氯化铵结晶温度、氯化铵潮解点温度和相对湿度。结果表明:相较于经验的露点温度预测方法,通过引入潮解点、划分系统“湿环境”温度范围判断氯化铵垢下腐蚀风险区域的方法与实际腐蚀案例更为切合;在3种油相含水条件下,换热器管束存在氯化铵垢下腐蚀的“湿环境”温度范围分别为:50~103 ℃,50~161 ℃,50~176 ℃;随着油相中含水量的提高,“湿环境”腐蚀区域逐渐向高温部位迁移,预计铵盐导致的垢下腐蚀将会愈加严重。 相似文献