Hasil untuk "Oils, fats, and waxes"

Ahmed Zoeir, Najme Talebi, Yousef Kazemzadeh et al.

Abstract Parameters like sediment’s origin, transport distances or next influencing factors such as cementation or dissolution, cause almost all natural porous media to exhibit some degree of anisotropy. Using the X-ray CT scanning approach to provide a virtual environment for the calculation of such properties has its own issues, including its low resolution, which gives an incomplete description of internal structure, along with its relatively high costs. Porous media can be reconstructed with the help of statistical techniques from existing high-resolution thin section images. In this work, in this article, a micro-CT file available on the Imperial College website is first selected, which has been obtained from a disordered anisotropic sandstone core sample. specific statistical algorithms are applied to the top and side images of the core sample, which represent the input images for the Multiple-Point Statistics (MPS) technique. After that, to construct artificial anisotropic media models, Optimization algorithms are used to polarize the phase occurrence potentials in the principal directions, which are obtained from the two thin-section images. Results show that applying optimization algorithms to polarize occurrence potential functions can effectively develop artificial porous media that exhibit tensor properties closely matching those calculated from high-resolution micro-CT images of the actual sandstone core sample, such as permeability and thermal conductivity tensors.

Lies Beers, Raffaella Mulas

We introduce and study Fair and Tolerant colorings (FAT colorings), where each vertex tolerates a given fraction of same-colored neighbors while fairness is preserved across the other coloring classes. Moreover, we define the FAT chromatic number $χ^{\mathrm{FAT}}(G)$ as the largest integer $k$ for which $G$ admits a FAT $k$-coloring. We establish general bounds on $χ^{\mathrm{FAT}}$, relate it to structural and spectral properties of graphs, and characterize it completely for several families of graphs. We conclude with a list of open questions that suggest future directions.

Joshua Hinman

The fatness of a 4-polytope or 3-sphere is defined as $(f_1+f_2-20)/(f_0+f_3-10)$. We construct arbitrarily fat, strongly regular CW 3-spheres that are both shellable and dual shellable. These spheres have $f$-vectors $(Θ(n),Θ(nα(n)),Θ(nα(n)),Θ(n))$, where $α$ is the inverse Ackermann function.

Stiéphen Pradal

The category fat Delta, introduced by J. Kock, is a modification of the simplex category where the degeneracies behave weakly. The objective of this note is to provide tools for working with fat Delta. In particular, we identify three types of morphisms: degenerated, standard and vertical faces, and establish six relations between these classes. We then show that fat Delta is generated by these morphisms and relations.

Valentino Smaldore, Corrado Zanella, Ferdinando Zullo

In this work, we introduce $(r,i)$-regular fat linear sets, which are defined as linear sets containing exactly $r$ points of weight $i$ and all other points of weight one. This notion generalizes and unifies existing constructions; scattered linear sets, clubs, and other previously studied families are special cases. We present new classes of regular fat linear sets in PG$(k-1,q^n)$ for composite $n$ and study their equivalence classes. Finally, we show that regular fat linear sets naturally yield three-weight rank-metric codes, which we use to obtain bounds on their parameters.

Ejaz Ahmed, Huajie Zhang, Mert Aybar et al.

Fluid imbibition into porous media featuring nanopores is ubiquitous in applications such as oil recovery from unconventional reservoirs and material processing. While the imbibition of pure fluids has been extensively studied, the imbibition of fluid mixture is little explored. Here we report the molecular dynamics study of the imbibition of model crude oil into nanometer-wide mineral pores, both when pore walls are dry and prewetted by a residual water film. Results show the fastest imbibition and quickest propagation of molecularly thin precursor films ahead of the oil meniscus in the dry pore system. The presence of a thin water film on pore walls corresponding to an environmental relative humidity of 30% slows down but still allows the spontaneous imbibition of single-component oil. Introducing polar components into the oil slows down the imbibition into dry nanopores, due partly to the clogging of the pore entrance. Strong selectivity toward nonpolar oil is evident. The slowdown of imbibition by polar oil is less significant in the prewetted pores than in dry pores, but the selectivity toward nonpolar oil remains strong.

Shamsutdinova L.L., Nikiforova L.V., Dmitrieva T.V. et al.

Descriptions of the local stratotypes of the Lower Silurian Formations of the Bolshezemelsk area of the Timan-Pechora region are provided and their geological and geophysical sections are presented. For the Makarikha Formation, the composite section of the parametric well Sandivey 31 and the exploratory well Sandivey 41 are proposed as the local stratotype. For the Sandivey Formation, the stratotype was established in the section of the well Sandivey 7, for the Veyak Formation, the composite stratotype was established in the parametric wells Zapadno-Veyak 1 and Severo-Salyukin 1. All wells are located in the territory of the Khoreyver depression, where commercial hydrocarbon accumulations are confined to the Lower Silurian strata.

Ai Xingyu, Xing Yuhan, Cai Xiaolei et al.

The characteristics of oil droplet flow and separation in shallow annular multi-layer counter-flow channels have been inadequately investigated.In this paper,the flow and separation of dispersed oil droplets in shallow annular counter-flow channels and the velocity distribution in shallow multi-layer flow channel were analyzed by using computational fluid dynamics(CFD)methods.The results indicate that the plate length required for the oil droplet floating upward in the shallow annular counter-flow channel to the surface of the inclined plate is 96 mm,less than the theoretical plate length(122 mm).The inter-layer velocity distribution in the shallow channel has a great impact on the separation efficiency,and the velocity at the inlet of the lower channel peaks at 0.008 05 m/s.The oil droplet may encounters a cross flow when it floats upward in the shallow annular multi-layer channel,which will impede greatly the separation efficiency in the channel.The sliding distance is a key factor influencing the separation efficiency.When the plate length is 350 mm and the grain size of oil droplet is 50 μm,the sliding distance accounts for 38.35% of the plate length.The research findings provide theoretical support for the innovative design and optimization of compact produced water treatment equipment based on the theory of shallow settling and enhanced separation.

黄欣宇1，夏晓红1，韩佳欣1，褚艺1，郄文彬2，韩彩静1，王霞1，3，张丰香1,3HUANG Xinyu1, XIA Xiaohong1, HAN Jiaxin1, CHU Yi1, QIE Wenbin2, HAN Caijing1, WANG Xia1,3, ZHANG Fengxiang1,3

为了更好地对小磨芝麻香油进行质控，在芝麻焙炒、石磨磨浆、水墩油3个主要工艺过程结束时取样，对不同工艺阶段芝麻油的色泽、酸值、过氧化值、脂肪酸组成及风味进行了检测。结果表明：水墩油过程使芝麻油有最大的a值和b值，分别为12.84和89.36；焙炒和石磨磨浆过程芝麻油的酸值不断降低，经水墩油之后又有所上升；与未焙炒的芝麻油相比，焙炒使芝麻油的多不饱和脂肪酸含量略有增加；电子鼻检测结果与GC-MS结果一致，焙炒和石磨磨浆过程所得芝麻油的风味相似，而水墩油使芝麻油风味物质种类增多，风味更强。综上，除焙炒过程外，水墩油也是影响小磨芝麻香油品质，特别是色泽和风味的关键环节，应加强对该阶段小磨芝麻香油风味物质变化与形成的研究。 In order to better control the quality of ground fragrant sesame seed oil, the color, acid value, peroxide value, fatty acid composition and flavor of sesame seed oil in different process stages were measured by sampling at the end of three main processes: sesame seed roasting, millstone grinding and oil separation by oscillation (including water adding and mixing). The results showed that the process of oil separation by oscillation made sesame seed oil have the largest a value and b value, which were 12.84 and 89.36, respectively. The acid value of sesame seed oil decreased continuously during roasting and millstone grinding, but increased after oil separation by oscillation. Compared with sesame seed oil obtained with unroasted sesame seed, roasting increased the polyunsaturated fatty acids content slightly. The results of electronic nose detection were consistent with those of GC-MS. The flavor of sesame seed oil obtained by roasting and millstone grinding was similar, while the variety of flavor substances in sesame seed oil increased and the flavor was stronger after oil separation by oscillation. In conclusion, besides the roasting process, oil separation by oscillation is also a key link that affects the quality of ground fragrant sesame seed oil, especially the color and flavor. It is necessary to strengthen the research on the change and formation of flavor substances in ground fragrant sesame seed oil at this stage.

邱国玉1，张鑫2,3，王小芳1，曾韦丹4，裴栋4，王晗3， 阚欢2，袁奖娟2,3QIU Guoyu1, ZHANG Xin2,3, WANG Xiaofang1, ZENG Weidan4, PEI Dong4, WANG Han3, KAN Huan2, YUAN Jiangjuan2,3

旨在为油橄榄作为食品应用提供科学依据，以田园1号、佛奥、鄂植8号、豆果及柯基5种油橄榄果为研究对象，参考国家标准对油橄榄果中主要营养成分、羟基酪醇和橄榄苦苷含量，矿物质元素、氨基酸和脂肪酸组成及含量等进行测定，并通过主成分分析对5种油橄榄果的综合品质进行评价。结果表明：油橄榄果中含量较多的是水分、脂肪和膳食纤维，依次为60.50~68.20 g/100 g、10.20~20.00 g/100 g 和7.03~13.50 g/100 g；矿物元素中K元素含量最高，Na元素仅在佛奥和柯基中检出，Zn元素仅在鄂植8号、豆果、柯基中检出；5种油橄榄果的必需氨基酸含量均占总氨基酸含量的43%左右，与FAO/WHO推荐人体每日所需摄入氨基酸比例接近；氨基酸评分最高的是苯丙氨酸+酪氨酸，其中与FAO/WHO标准最接近的品种是鄂植8号；5种油橄榄果中共检出15种脂肪酸，其中油酸、亚油酸和棕榈酸含量较高；油橄榄果中均含有橄榄苦苷和羟基酪醇，除田园1号外，其余品种中羟基酪醇含量均高于橄榄苦苷；综合评分最高的品种是柯基。综上，油橄榄果中营养成分较为丰富，在食品深加工等方面具有较高的开发利用价值。In order to provide scientific basis for the application of Olea europaea L. fruits as a food product, with five kinds of Olea europaea L. fruits namely Tianyuan No. 1, Foao, Ezhi No. 8, Douguo and Keji as research objects, the contents of basic nutrients, hydroxytyrosol and oleuropein, and the compositon and contents of mineral elements, amino acids and fatty acids were determined by the national standard methods. The comprehensive quality of five kinds of Olea europaea L. fruits was evaluated through principal component analysis. The results showed that the basic nutrients in five kinds of Olea europaea L. fruits were mainly water, fat and dietary fiber, and the contents were 60.50-68.20 g/100 g, 10.20-20.00 g/100 g and 7.03-13.50 g/100 g, respectively. The content of K in mineral elements was the highest. The element Na was only detected in Foao and Keji, and the element Zn was only detected in Ezhi No.8, Douguo and Keji. The content of essential amino acid in five kinds of Olea europaea L. fruits was accounted for about 43% of the total amino acid content, which was close to the FAO/WHO recommended daily intake of amino acids. The highest amino acid score was phenylalanine (Phe) + tyrosine (Tyr), and the closest one to FAO/WHO standards was Ezhi No. 8. A total of 15 fatty acids were detected in five kinds of Olea europaea L. fruits, mainly oleic acid, linoleic acid, and palmitic acid. Except for Tianyuan No. 1, the content of hydroxytyrosinol was higher than that of oleuropein in other varieties. The variety with the highest overall rating was Keji. In summary, Olea europaea L. fruits are rich in nutrients and have high development and utilization value in areas such as food deep processing.

S. Barroso-Solares, M. G. Zahedi, J. Pinto et al.

Herein we present the fabrication of hydrophobic and oleophilic poly(methyl methacrylate) based nanocomposite fibrous mats with magnetic properties, and their utilization for oil removal from stable water oil emulsions.

Alex V. Lukyanov, Hanan Hozan, Tristan Pryer et al.

We hypothesize that the spread of oil slicks on the water's surface during oil spills is significantly influenced by water wave motion at the initial or intermediate spreading stages, well before emulsification processes have a substantial impact on the oil film's state. We demonstrate that the spreading dynamics of an oil slick on the water surface are facilitated by water waves, employing the thin film approximation. It is shown that water wave motion can rapidly deplete any oil slick, reducing the oil layer's thickness to nearly zero. This mechanism may act as a precursor to emulsification processes, leading to the accelerated depletion of oil spills into a distribution of droplets that form an emulsion.

李群1，李颜1，董绪燕2，赵长建1，艾合买提江·艾海提1，刘军1 LI Qun1，LI Yan1，DONG Xuyan2，ZHAO Changjian1， AIHAMATIJIANG Aiheti1，LIU Jun 1

为提高甜瓜籽利用率，采用超声辅助提取工艺提取甜瓜籽油，以甜瓜籽油得率及DPPH自由基清除率为指标，通过单因素实验研究超声时间、超声温度、料液比、浸提时间对甜瓜籽油提取的影响，在此基础上采用响应面实验对提取工艺条件进行优化，并测定提取的甜瓜籽油理化指标、总酚含量、甾醇和脂肪酸组成及含量。结果表明:甜瓜籽油的最佳提取工艺条件为浸提时间3 h、料液比1∶ 7.7、超声温度43 ℃、超声时间41 min，在此条件下甜瓜籽油得率为25.64%，DPPH自由基清除率为60.66%；制备的甜瓜籽油酸值（KOH）为0.52 mg/g，过氧化值为0.00 mmol/kg，碘值（I）为133.38 g/100 g，总酚含量为8.72 mg/100 g;甜瓜籽油中共检出5种脂肪酸，其中亚油酸含量最高，为66.68%，共检出7种甾醇，总含量达306.10 mg/100 g，其中β-谷甾醇含量最高，为138.60 mg/100 g。甜瓜籽油营养价值较高，可作为食用油进一步开发利用。 In order to improve the utilization of Cucumis melo L.seeds, Cucumis melo L.seed oil was extracted by ultrasonic-assisted extraction.The yield of Cucumis melo L.seed oil and DPPH radical scavenging rate were taken as indicators, and the effects of ultrasonic time, ultrasonic temperature, solid-liquid ratio, and extraction time on the extraction of Cucumis melo L.seed oil were investigated by single factor experiment,then the extraction conditions were optimized by response surface methodology.The physicochemical indexes, total phenol content, composition and contents of sterol and fatty acid of extracted Cucumis melo L.seed oil were determined.The results showed that the optimal extraction conditions were obtained as follows: ultrasonic time 41 min,ultrasonic temperature 43 ℃,solid-liquid ratio 1∶ 7.7, and extraction time 3 h. Under these conditions, the yield of Cucumis melo L.seed oil was 25.64%, and the DPPH radical scavenging rate was 60.66%. The acid value,peroxide value, iodine value and total phenol content of Cucumis melo L.seed oil were 0.52 mgKOH/g, 0.00 mmol/kg，133.38 gI/100 g, and 8.72 mg/100 g，respectively.A total of five fatty acids were detected in Cucumis melo L. seed oil, of which linoleic acid had the highest content of 66.68%, and seven sterols were detected, with a total content of 306.10 mg/100 g, of which β-sitosterol had the highest content of 138.60 mg/100 g. Cucumis melo L.seed oil has high nutritional value and can be further developed and utilized as an edible oil.

Norio Iwase, Yuki Kojima

The main purpose of this paper is to introduce a new smooth version of a CW complex named a fat CW complex, and to show that it includes all closed manifolds, because existing smooth versions of CW complexes (e.g. [Iwa22]) do not have such property. We also verify that de Rham theorem holds for a fat CW complex and that a regular CW complex is reflexive in the sense of Y. Karshon, J. Watts and P. I-Zemmour. Further, any topological CW complex is topologically homotopy equivalent to a fat CW complex. So, a fat CW complex enjoys many nice properties.

Phan Van Thien

We prove invariant of the regularity index of fat points under changes of the linear subspace containing the support of the fat points. Then we show that Segre's bound is attained by any set of s non-degenerate equimultiple fat points in $\mathbb P^n$, $s\le n+3$. We also give an example showing that there always exists a set of n+4 non-degenerate equimultiple fat points in $\mathbb P^n$ such that Segre's bound is not attained.

Henrik Wachtmeister, Johan Gars, Daniel Spiro

Following Russia's invasion of Ukraine, Western countries have looked for ways to limit Russia's oil income. This paper considers, theoretically and quantitatively, two such options: 1) an export-quantity restriction and 2) a forced discount on Russian oil. We build a quantifiable model of the global oil market and analyze how each of these policies affect: which Russian oil fields fall out of production; the global oil supply; and the global oil price. By these statics we derive the effects of the policies on Russian oil profits and oil-importers' economic surplus. The effects on Russian oil profits are substantial. In the short run (within the first year), a quantity restriction of 20% yields Russian losses of 62 million USD per day, equivalent to 1.2% of GDP and 32% of military spending. In the long run (beyond a year) new investments become unprofitable. Losses rise to 100 million USD per day, 2% of GDP and 56% of military spending. A price discount of 20% is even more harmful to Russia, yielding losses of 152 million USD per day, equivalent to 3.1% of GDP and 85% of military spending in the short run and long run. A price discount puts generally more burden on Russia and less on importers compared to a quantity restriction. In fact, a price discount implies net gains for oil importers as it essentially redistributes oil rents from Russia to importers. If the restrictions are expected to last for long, the burden on oil importers decreases. Overall, both policies at all levels imply larger relative losses for Russia than for oil importers (in shares of their GDP). The case for a price discount on Russian oil is thus strong. However, Russia may choose not to export at the discounted price, in which case the price-discount sanction becomes a de facto supply restriction.

Leonardo F. Cavenaghi

In his unpublished notes on fat bundles, W. Ziller poses a compelling question: given a fat principal $G$-bundle $(P, g) \rightarrow (B, h)$ with $\dim G = 3$, and $g$ representing a Riemannian submersion metric ensuring that the $G$-orbits are totally geodesic, can one modify $h$ to render all vertical curvatures equal to $1$? In this note, we establish a rigidity result for fat Riemannian foliations with bounded holonomy and a specific curvature constraint. Our result addresses Ziller's question for fat fiber bundles with compact structure groups, considering connected compact total spaces under a curvature constraint that holds on various examples, such as locally symmetric spaces. Additionally, we assume that all vertizontal curvatures coincide at a point.

Ayaz Zeynalov, Kristina Tiron

Oil price fluctuations severely impact the economies of both oil-exporting and importing countries. High oil prices can benefit oil exporters by increasing foreign currency inflow; however, an economy can suffer from a weakening of the manufacturing sectors and experience a significant downtrend in the country's price competitiveness as the domestic currency appreciates. We investigate the oil price fluctuations from Q1, 2004 to Q3, 2021 and their impact on the Russian macroeconomic indicators, particularly industrial production, exchange rate, inflation and interest rates. We assess whether and how much the Russian macroeconomic variables have been responsive to the oil price fluctuations in recent years. The outcomes from VAR model confirm that the monetary channel is more responsive to oil price shocks than the fiscal one. Regarding fiscal channel of the oil price impact, industrial production is strongly pro-cyclical to oil price shocks. As for the monetary channel, higher oil price volatility is pressuring the Russian ruble, inflation and interest rates are substantially counter-cyclical to oil price shocks.

XU Jianping, YUAN Yuanda, XIE Qing et al.

Traditionally, laboratory testing and measurement are considered to be the most reliable characterization methods. However, in many cases, due to the unclear understanding of the sensitivity to the range of reservoir properties and local changes of heterogeneous reservoir properties, and based on the oversimplified assumptions, the feature prediction obtained by this deterministic strategy is highly uncertain. In recent years, molecular dynamics （MD） simulation has received extensive attention in the study of reservoir rock, fluid properties and their interactions, as well as at the atomic level. In MD simulation, interesting properties are extracted from the time evolution analysis of atomic position and velocity through the numerical solution of Newton's equations for all atomic motions in the system. This technology can help to carry out the computer experiments which can be used to do the experiments that may not be able to complete, with high cost or very dangerous. In this paper, we review the MD simulation technology and its application in the study of oil displacement mechanism and properties of oil displacement agent, and expounds the theoretical concept and program of MD, especially in the analysis of polymer flooding. It will provide useful guidelines to characterize reservoir rocks and fluids and their behaviors in various reservoirs, help to better optimize the operation of design and production plan, and provide a theoretical basis for the development of polymer flooding technology in oilfields.