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The source of oil and gas in the Tarim Basin's platform has always been controversial. The Lower Cambrian Yurtusi Formation and the Xidashan Formation–Xishanbulak Formation argillaceous source rocks are an important set of oil source series in the basin. Based on the principle of conservation of matter, this paper calculates the hydrocarbon expulsion amount of the source rock. Using a phase state hydrocarbon expulsion amount characterization model, the paper reconstructs the evolution process of the hydrocarbon expulsion phase state of the source rock. According to the characterization model of hydrocarbon expulsion dynamics, the relative contribution of each force to hydrocarbon expulsion is evaluated. The hydrocarbon expulsion geologic model of argillaceous source rocks in the Lower Cambrian in the Tarim Basin is established. The results show that this set of source rocks can serve the main source rocks in the basin. The hydrocarbon expulsion of the Lower Cambrian argillaceous source rocks in the Tarim Basin can be divided into three stages. In the first stage, the hydrocarbon expulsion phase is dominated by the water‐soluble and diffusion phases. The conversion of clay minerals into dehydration and diffusion forces is the main driving force for the hydrocarbon expulsion. In the second stage, the oil and gas expulsion present the characteristics of multiphase and multidynamic coexistence. In the third stage, the phase state of oil and gas expulsion is mainly free phase. The capillary force difference and the thermal expansion force of the fluid rock are the main driving forces for oil and gas expulsion. The research results of this paper can deepen the understanding of the hydrocarbon expulsion mechanism of the set of source rocks, and then guide oil and gas exploration. [ABSTRACT FROM AUTHOR]

There is a large body of literature that examines different dimensions of corporate social responsibility (CSR) in Africa, with many focusing on the false promises of these corporate initiatives. Contrary to simplistic claims of CSR being merely window‐dressing, however, this paper reveals that although several rhetorical proclamations underpin the idea, such statements are often given instrumental meaning through diverse mechanisms (e.g., interpretation of cues toward the proactive (re)construction of identity, (inter)subjective discourses on social legitimacy, and acts of "issue selling") that help to enact particular characteristics of the corporation. The paper specifically employs the organizational concepts of sensemaking and sensegiving to explain how, through CSR activities, hydrocarbon companies in Ghana construct and (re)affirm a particular reality for its stakeholders. The findings suggest that by having significant leverage over the (re)construction of its identity and claims around social legitimacy and performance, the corporation gives sense to and further sustains its authority over societal norms and expectations around what social responsibility entails. The evidence presented contributes to scholarship that considers the corporation as a complex nexus of multiple relations, contested narratives, and practices. [ABSTRACT FROM AUTHOR]

Shale reservoir has strong heterogeneity in mineral composition and oil content even at a short distance in the same interval. To better understand the accumulation mechanism of shale oil and hydrocarbon migration tendency in the interval, and explore the main influencing factors of distribution. This paper employed various methods, including thin‐section observation, TOC (total organic matter (OM)) analysis, rock pyrolysis, Soxhlet extraction, group component separation, and GC–MS (gas chromatography mass spectrometry) analysis of saturated hydrocarbons. The shale oil samples were collected from an exploratory well in the Songliao Basin, and the distribution and enrichment characteristics of shale oil interlayers were analysed. The results show that the first member of Qingshankou Formation (K2qn1) could be divided into six small layers. From Q1 to Q6, the lithofacies could be divided into three types: high‐frequency laminar shale, massive shale, and bioclastic shale. The lacustrine matrix shale of K2qn1 in Songliao Basin has medium TOC, and high oil contents, OM conversion rate. The TOC ranges from 1.5 to 4.2 wt%, S1 varies between 1.4 and 4 mg/g, S2 falls within the range of 4 to 10.6 mg/g, Tmax ranges from 351 to 497°C, and the OSI varies between 57 and 115.34 mg HC/g rock. The lower part of the K2qn1, Q1–Q4, characterized by high‐frequency laminar shale, contained residual shale oil, while the upper part of the K2qn1, Q5 and Q6, characterized by bioclastic shale and massive mudstone, and are dominated by in‐situ type shale oil. The crude oil in K2qn1 is homologous, and primarily undergoes micro‐migration. The Q5–Q6 section has the highest light oil content, while other regions with notable light components are located in the middle of Q1, the upper sections of Q2, Q3, and Q4.Q1–Q4 are primarily composed of residual shale oil, whereas Q5–Q6 is primarily composed of in‐situ shale oil, and the primary micro‐migration direction of shale oil occurs laterally within Q1–Q4. The lateral migration of each section mainly occurs at the upper part of Q3 and Q4, the lower part of Q1 and Q2, the bottom of Q5, and the interface between Q6 and the second member of Qingshankou formation (K2qn2). The block mudstone retains in‐situ shale oil, especially light hydrocarbons. Within the high‐frequency laminar shale, there is strong horizontal connectivity, and lateral hydrocarbon expulsion serves as the primary mechanism for micro‐migration in Q1–Q4. This paper can provide reference values for K2qn1 Formation shale oil and the migration and differential reservoir formation of medium and high‐maturity matrix shale oil. [ABSTRACT FROM AUTHOR]

The separation of short‐chain hydrocarbon mixtures is of great significance for the efficient utilization of fossil energy. Liquid–liquid extraction, as one of the commonly used treatment methods, has significant advantages in terms of operation conditions and energy consumption. As a new dipolar aprotic solvent developed in recent years, dihydrolevoglucosenone (Cyrene) has a wide range of sources and a green composition. In this paper, the liquid–liquid equilibrium and extraction mechanism of Cyrene and five hydrocarbon mixtures with short carbon chains, including toluene/n‐heptane, toluene/cyclohexane, n‐hexane/cyclohexane, n‐pentane/pentene, and n‐hexane/hexene, have been studied by combining experiments and quantum chemical calculations, and the extraction effects under different conditions have been investigated. The results showed that the forces between Cyrene and the different solutes are mainly van der Waals (VDW) forces dominated by dispersion forces, with some weak hydrogen bonds present. Due to the difference in interaction energy, the order of extraction selectivity was toluene‐n‐heptane > toluene‐cyclohexane > n‐hexane‐hexene > n‐hexane‐cyclohexane > n‐pentane‐pentene, and the order of distribution coefficients of the extracted components (aromatics, olefins, and cycloalkanes) was toluene > pentene > hexene > cyclohexane. The dissolution processes of all systems were heat‐absorbing, and they all reached the extraction equilibrium within 60 s. The reliability of the experimental data was verified using the Othmer–Tobias equation and the Hand equation, and the binary interaction parameters of all systems were obtained by the non‐random two liquid (NRTL) model, providing basic data and references for the subsequent studies on the separation of Cyrene and short‐chain hydrocarbons. [ABSTRACT FROM AUTHOR]

The spatiotemporal coupling relationship between deep hydrocarbon fluid and sandstone uranium mineralization within the shallow buried red‐variegated clastic rocks in the Qianjiadian area of the Songliao Basin remains a topic of controversy. This paper aims to provide a comprehensive understanding of the source, nature and exudative age of deep exotic hydrocarbon, as well as the interaction mechanism and alteration process between hydrocarbon fluid and clastic rock. To achieve this, various methods were employed, including acidolysis hydrocarbon test (AHT), clay x‐ray diffraction (XRF), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), carbon isotope analysis (CIA) and LA‐ICP‐MS U–Pb isotopic dating. The results indicate that some tight sandstones from the Qingshankou Formation in Dalin uranium deposit exhibit high acidolysis hydrocarbon content (AHC), reaching n × 104 μL/kg, and predominantly consisting of low mature oil‐type gas. Local microscopic observations reveal pore fluorescence and hydrocarbon‐bearing inclusions with nattier blue tone. Furthermore, the kaolinites present in the ore area's sand‐bodies show a significantly higher content anomaly, commonly exceeding >50%, compared to the same layer in peripheral regions. Extensive dissolutions of lithic grains and feldspars are observed, along with the widespread occurrence of ferro‐dolomites and colloidal pyrites. Additionally, exotic asphaltenes are sporadically developed in localized areas. These findings provide evidence that the sand‐bodies experienced a significant exfiltration event of external gaseous fluids. The light carbon isotopes (δ13CV‐PDB ranging from −33.26‰ to −30.06‰) of group components and n‐Alkane suggest that the hydrocarbon originates from the source rock of the Lower Cretaceous Jiufotang Formation. A detailed two‐stage alteration sequence caused by acidic and reducing hydrocarbon is clarified, encompassing acidic corrosion, kaolinization, pyritization, silification and asphaltization during the exudation stage, followed by ferro‐dolomitization in the later cessation stage. Notably, vermicular secondary kaolinites, formed through the interaction between acidic hydrocarbon fluid and low‐temperature meteoric groundwater, serve as significant markers for the exfiltration of deep hydrocarbon fluid. In‐situ U–Pb dating of hydrocarbon‐bearing ferro‐dolomite yielded absolute exfiltration ages of 63.54 ± 4.13 and 65.93 ± 3.35 Ma. By integrating the tectonic–sedimentary–fluid evolution history and uranium mineralization characteristics in the study area, a three‐stage superimposed metallogenic model is proposed for the Upper Cretaceous red‐variegated layers: (1) the sedimentary and diagenetic stage of the target layer during the Late Cretaceous, (2) the predominant hydrocarbon exudation stage at the end of the Late Cretaceous, and (3) the main uranium mineralization stage since the Paleogene. This study enhances our understanding of coupled‐genetic sandstone‐type uranium deposit in a sedimentary basin and provides valuable guidance for prospecting similar red‐variegated beds in the Songliao Basin and other sedimentary basins worldwide. [ABSTRACT FROM AUTHOR]

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Copyright of Canadian Geographer is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Yinggen‐Ejinaqi Basin (YEB) is located in the central‐southern part of the Central Asian Orogenic Belt (CAOB). Tectonically, the basin is situated at the intersection between the eastern and western CAOB, where Late Palaeozoic strata were well exposed. Hence, it offers a great opportunity to study the deep strata of the eastern CAOB. In this paper, based on extensive studies of Upper Palaeozoic field outcrops and reanalysis of associated geochemical and geochronological data in previous research, the local stratigraphic correlation is established, and the tectonic evolution, sedimentary filling, sedimentary characteristics, and petroleum system of the YEB are discussed. It is revealed that: (a) The filling characteristics of the Upper Palaeozoic strata in YEB are closely related to the closure of the Paleo‐Asian Ocean (PAO). YEB underwent subduction‐related compression during the initial extensional phase of the fore‐arc basin from the Viséan to the Serpukhovian (late Early Carboniferous). During the Bashkirian–Sakmarian interval (Late Carboniferous to Early Permian), it was in subduction‐related fore‐arc and postarc rifting phases. During the Artinskian–Capitanian (Early‐Middle Permian) times, it was in an intracontinental rifting‐depression phase. During the Wuchapingian (Late Permian), it was in an intracontinental compressional phase. Tectonostratigraphy, tectonic evolution, and hydrocarbon potential assessments of the study area show that the Zhusileng Hangwula‐Tost Ul tectonic zone (ZHTUTZ) and southwestern part of Querrshan‐Atasbogd tectonic zone (QATZ) are identified as the main prospective areas for the exploration in the YEB. (b) According to the tectonostratigraphic analysis, tectonic evolution and hydrocarbon system of Carboniferous–Permian in the YEB, the YEB has similar attributes to the basin province in western CAOB (e.g., Santanghu and Junggar basins) and eastern CAOB (Erlian, Songliao Basin). To explore commercial oil and gas in the deeper strata (Carboniferous–Permian) of the eastern CAOB basins, further tectonostratigraphic analyses and comprehensive assessment on hydrocarbon potentials are necessitated in the near future. [ABSTRACT FROM AUTHOR]

Understanding the features of the hydrocarbon generation and expulsion of the Upper Triassic Xujiahe Formation (T3x) source rocks is important to properly guide petroleum exploration in the Xujiahe Formation in the Sichuan Basin. Based on mass balance, the hydrocarbon generation and expulsion from the T3x source rocks are characterized in this paper through a method (i.e., hydrocarbon generation potential index using pyrolysis data) different from that used in previous studies. The threshold and peak of hydrocarbon expulsion are determined to be Ro = 0.9% and 1.15%, respectively. The amounts of hydrocarbon generated and expelled in the T3x source rocks are 4,525.5 × 108 and 2,420.5 × 108 t, respectively. Moreover, three hydrocarbon expulsion regions T3x have been identified in the Sichuan Basin. On the basis of the hydrocarbon generation and expulsion features of the source rocks and the distribution of the oil‐and‐gas reservoirs, the quantitative model of the hydrocarbon accumulation probability under the control of the T3x source rock is established via single‐factor regression analysis. The predictions obtained through this analysis show that the favourable oil‐and‐gas exploration areas in the Xujiahe Formation are distributed in the Qionglai, Chengdu, and Deyang regions, as well as in the west of Yilong region. Further, the results show that 78% of the discovered oil‐and‐gas reservoirs are located in the predicted favourable and relatively favourable oil‐and‐gas exploration areas. [ABSTRACT FROM AUTHOR]

The exploration of high production, natural gas wells (>106 m3/d) has been extremely successful in the Gaoshiti and Moxi areas of the Leshan–Longnvsi paleo‐uplift, in the west‐central Sichuan Basin. This paper focuses on the Sinian and Cambrian reservoirs from the Gaoshiti and Moxi areas, where a dataset of new trace elements in bitumen and potential source rock is reported and where hydrocarbon‐source correlation is attempted based on trace elements characteristics of the 12 potential source rocks and 22 bitumen samples. Results show that the bitumen from the three reservoirs can be distinguished from each other using trace element distribution patterns and redox‐ and provenance‐sensitive elemental ratios. Bitumen in the second and fourth members of the Sinian Dengying Formation were derived primarily from the third member of the source rocks of the Dengying Formation, which represents a self‐sourced paleo‐petroleum system. In contrast, bitumen in the reservoirs of the Cambrian Longwangmiao Formation is derived from the Cambrian Qiongzhusi Formation and third member of Dengying Formation. The trace element method used in this study improves our understanding of the complex hydrocarbon–source relation and confirm the potential target for petroleum exploration in the study area. [ABSTRACT FROM AUTHOR]

Groundwater pollution is regarded as one of the most serious environmental risks related to underground coal gasification (UCG). In this paper, two kinds of high efficient phenol degrading strains were isolated from activated sludges, which were obtained from coking wastewater and domestic sewage, and were named as JC and WX correspondingly. The isolated bacteria were identified by a combination method of physiological and biochemical analyses and 16SrDNA sequencing. The total organic carbon (TOC) and organic pollutants in gas washing water produced from the UCG model test of lignite were measured by TOC analyzer and gas chromatography‐mass spectrometer (GC‐MS), and the microbial degradation effect of gas washing water was finally studied by the isolated bacteria. The results reveal that JC and WX bacteria were pseudomonas aeruginosa and achromobacter xylosoxidans, respectively, and that phenolic compounds were the main organic pollutants in gas washing water, taking 95.01 percent of the total organics. The removal of TOC exceeded 72.9%, the degradation efficiency of total organic pollutants (TOM) achieved 79.03% and the degradation efficiency of phenolic compounds could be 98.76% by JC and 99.04% by WX, respectively. Most benzene series (BTEX) could not be degraded by the screened two kinds of bacteria, whereas the concentrations of BETX were increased. Some short‐chain hydrocarbon compounds with low concentrations were also detected in wastewater after microbial degradation. [ABSTRACT FROM AUTHOR]

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The Mesoproterozoic Jixian System is widely distributed at the south‐western margin of the Ordos Basin. It is mainly dominated by siliceous laminated algal micritic dolomite that is a set of potential carbonate source rocks. The magmatic activities at the south‐western margin of the Ordos Basin were frequent and intensive, and the Tongcheng intrusion exposed in this area has an intrusive contact relationship with the Jixian System. This paper uses geochemical methods to study the influence of magmatism to lithology, physical properties, hydrocarbon generating property, and geochemistry of the Jixian System. Analysis data reveal that, with the increasing distance to the intrusion, the porosity, permeability, and content of dolomite, trace elements, and rare earth elements in surrounding rock decrease while the density and silica content increase gradually. In addition, the parameters have a weakening trend about adsorbed hydrocarbon (S1), pyrolysis hydrocarbon (S2), hydrocarbon generating potential (S1 + S2), and pyrolysis peak temperature (Tmax). The results suggest that the magmatic hydrothermalism and the thermal effect of magmatic intrusion changed the physical and geochemical characteristics of the surrounding rock and promoted the hydrocarbon generation of organic matter. However, these characteristics reflect that the magmatic activities only have a relatively small effect on the laminated algal micritic dolomite in Jixian System without a destructive effect at the south‐western margin of the Ordos Basin. The petroleum potential of the Jixian System is worthy to be further explored. [ABSTRACT FROM AUTHOR]

The Lianglitage Formation (also named Lianglitag Formation) is an important hydrocarbon reservoir in the Tarim Basin; the reef and shoal facies of this formation have previously been extensively investigated. The paleokarst of the formation related to a tectonic unconformity at the top of the Ordovician (Tg5) has, however, not been widely investigated. In this paper, we undertake a comprehensive study of the paleokarst by an integrated analysis of seismic data, well‐logging data, and core data. Several geomorphologic units that formed at the end of the Ordovician period are identified, including a fault‐thrust uplift high, inter‐uplifts sag, uplift platform, and fault‐thrust anticline; these units are controlled by west–east and northwest–southeast striking faults. The thickness of erosion is estimated to be 200 to 700 meters. The paleokarst is characterized by large and small caves, dense vugs, and dissolution fractures. Large caves predominantly developed in exposed areas and on the slopes. Dense vugs and small caves, features that contribute to premium hydrocarbon reservoirs, are generally tens of meters away from the unconformity, whereas dissolution fractures, predominantly filled by mud and silts, are situated in close proximity to the unconformity and faults. Four karst zones can be identified from vertical profiles: weathered crust (1–2 m thick), vertical infiltration zone (tens of meters thick), phreatic zone (tens to hundreds of meters thick), and a bottom zone that is largely unaffected by karstification. The karst of the Lianglitage Formation at the end of the Ordovician was mainly controlled by tectonic movement, paleogeomorphology, lithofacies, faults, and fractures. The karstification process is summarized in a karst model. [ABSTRACT FROM AUTHOR]

This paper examines the relationship between global energy security and climate change policy. There are growing concerns about the sustainability of the future supply of hydrocarbons. The energy system is the single largest source of anthropogenic greenhouse gases, therefore it is no surprise that decarbonising the supply of energy services is a key element of climate change policy. The central proposition of this paper is that the world faces a global energy dilemma: can we have secure, reliable and affordable supplies of energy and, at the same time, manage the transition to a low-carbon energy system? The paper is divided into five sections. The first section considers the contemporary challenges to global energy security, focusing on the possibility that in the future oil production might not be able to meet demand. The second section considers how the perils of climate change are forcing us to rethink the very meaning of energy security such that a low-carbon energy revolution is now called for. The third section explains that while the developed world is largely responsible for the anthropogenic carbon emissions currently in the atmosphere, a global shift in energy demand is underway and over the next 20 years it is the developing world that will contribute an ever-increasing share of global emissions. The fourth section introduces the notion of the global energy dilemma nexus to explain how the processes of globalisation are the driving force behind this global shift in energy demand and carbon emissions. The final section explains how the global energy dilemma nexus plays itself out in different ways across the globe. The conclusions suggest that human geography can make a significant contribution to social science research on energy security and climate change. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Chemical Engineering is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Zhuanghai area is located in the northern part of the Jiyang Depression, Bohai Bay Basin, which is a superimposed basin. In this basin, there are very thick Cenozoic sediments that unconformably overlie Lower Palaeozoic rocks, which form buried hills (topographic highs). Through core description and microscopic observations, the diagenetic characters, pore types, reservoir quality and the dissolution characteristics of the Lower Palaeozoic strata have been investigated in the study area. Organic and inorganic gas-liquid bi-phase inclusions with bright orange-yellow fluorescence are evidence of the dissolution of the compacted released water enriched in organic matter released from Palaeogene strata into the Lower Palaeozoic strata. The relatively high homogenization temperatures of fluid inclusions can help explain the temperature condition of secondary low-temperature hydrothermal minerals and the effects of dissolution of the compacted released water on the Lower Palaeozoic carbonates and hydrocarbons within the buried hills. The δ13C values of crystalline calcite in the high-angle fractures of Lower Palaeozoic rocks range from −0.08‰ to −3.5‰, well above those of primary carbonates of the Lower Palaeozoic. The very high values of δ13C of crystalline calcite suggest the effects of dissolution of the compacted released water on the Lower Palaeozoic carbonates. The paper analyses the effects of dissolution of the compacted released water and the character of the reservoir space of the Zhuanggu-10 well in the Zhuangxi Buried Hill and suggests that the Ordovician Majiagou Formation underwent significant dissolution because of the introduction of compacted released water and formed various secondary pores acting as a primary reservoir. The compacted released water that corroded the Lower Palaeozoic carbonates comes from the Palaeogene sediments in the adjacent Zhuangxi Sag. It migrated along the boundary fault of the sag to the Zhuangxi Buried Hill, modified the Lower Palaeozoic carbonates and caused the formation of deeply buried dissolution pores. The dissolution mode of the down-dip faulted block seepage as recognized in the Chengbei 305 to 307 wells is proposed to explain the pore distribution patterns of the buried hills in the research area. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Linked Articles: This article is part of a themed section on 8th European Workshop on Cannabinoid Research. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.10/issuetoc. [ABSTRACT FROM AUTHOR]

In this paper, O-alkylation of isovanillin with unusual phase transfer catalysts alkandiyl-α,ω-bis(dimethylalkylammonium bromide) dimeric surfactants (also known as gemini surfactants) is described. Some dimeric surfactants with simple hydrophobic alkyl chains and others with hydrophobic alkyl chains containing ester functionalities with different lengths were synthesized and characterized in our laboratory. The alkylation of isovanillin with alkyl halide was successively carried out in the presence of potassium carbonate and a phase transfer catalyst in tetrahydrofuran. The same reactions were also performed with both the traditional phase transfer catalyst tetrabutylammonium bromide and without any catalyst. The results were compared with those of dimeric surfactants. Consequently, it was expressed that alkandiyl-α,ω-bis(dimethylalkylammonium bromide) dimeric surfactants successively exhibit the character of phase transfer catalysts through environmentally friendly procedures under mild conditions. The most significant feature of this work is that dimeric surfactants have been determined to act as phase transfer agents. [ABSTRACT FROM AUTHOR]

In this paper, the effects of major asphaltene deposition model parameters, particle-particle collision, and particle-wall sticking efficiencies as well as asphaltene content in a hydrocarbon fluid on asphaltene deposition in both a Taylor-Couette device and production tubing are numerically studied. The possibility of an increase in asphaltene deposition rate as a result of adding asphaltene inhibitors is investigated. The computations show that this critical effect is achievable in a Taylor-Couette device operating in a batch regime only if the particle collision and the particle-wall sticking efficiencies are more than an order of magnitude higher than those identified for asphaltenes present in hydrocarbon fluids. Calculations of deposition in the Taylor-Couette device show also that an increase in the asphaltene content causes an increase in the rate of fluid depletion of particles able to deposit. The deposition calculations for a vertical pipe demonstrate that, due to continuous precipitation of primary particles along the tubing, a hydrocarbon fluid cannot be depleted of particles able to deposit; therefore the maximum deposit thickness always increases with an increase either in the major model parameters or the asphaltene content. Thus, the model parameter values indicating critical deposition regimes are different from those inherent to real hydrocarbon fluids; therefore, these regimes cannot be achieved in practical applications. [ABSTRACT FROM AUTHOR]

Abstract: Invited for this month's cover picture is the group of Prof. Dr. Andreas Hirsch from Friedrich Alexander University (Germany). The cover picture shows shell‐by‐shell coated nanoparticle ‘chameleons’—wet‐chemically surface‐modified nanoparticles that can reversibly adjust their dispersibility to entirely orthogonal solvent environments. Read the full text of their Full Paper at 10.1002/open.201800011. [ABSTRACT FROM AUTHOR]

It is proposed in this paper to extend the original group contribution method PPR78 to systems containing water, by combining it to the Cubic-Plus-Association (CPA) equation of state (EoS). Applying simple geometric combination rules, the binary interaction parameter kij(T) can be calculated from interaction parameters between hydrocarbon groups and water. This model, called the GC-PR-CPA is applied to predict hydrocarbons - water mutual solubilities over a wide temperature and pressure range, depending on available literature data. Group interaction parameters, here CH4, C2H6, CH3, CH2, CH, C, CHaro, CH2,cyclic, CHcyclic/Ccyclic, C2H4, CH2,alkene/CHalkene with H2O have been defined with solubility data. Predictions of the developed model have been validated against independent solubility data as well as water content in hydrocarbon rich phase. Predictions of the new model are in good agreement for light and medium hydrocarbons; however, some deviations are observed for heavier hydrocarbons. [ABSTRACT FROM AUTHOR]

Abnormal pressure is considered significant for the migration and accumulation of oil and gas. The purpose of this study is to present the lateral and vertical distribution of underpressure conditions in the Huimin Depression determined using the drill stem tests (DSTs) and the well log data. This paper also provides the origins of the underpressure both qualitatively and quantitatively, as well as the effects of the underpressure on the distribution of hydrocarbons. The results show two vertical underpressure units at depths of 1,500–2,500 m and 3,000–4,000 m with a pressure coefficient of 0.8–0.95. Laterally, the underpressure is mainly distributed in the Northern Tectonic Uplift Belt (NTUB) and Southern Slope Belt (SSB). The rock dilation and temperature reduction caused the pressure reductions of 3–4 and 1–3 MPa, respectively. The diffusion of natural gas plays a limited role on the underpressure. An analysis of the lateral seals of faults indicates that the underpressured regions developed in areas with faults with shale gouge ratio (SGR) values larger than 0.6. We propose that the widely distributed underpressure in the Huimin Depression is related to rock dilation, temperature reduction, and fault sealing. An analysis of hydrocarbon migration and reservoirs showed the pumping effect provided by the deficient pressure could make underpressured regions the primary targets for hydrocarbon accumulation, and in the Huimin Depression, underpressure might be more important than overpressure. [ABSTRACT FROM AUTHOR]

Fully formulated synthetic jet fuel is an aviation turbine fuel that does not contain petroleum‐derived kerosene and comprises the hydrocarbon compound classes n‐alkanes, isoalkanes, cycloalkanes, and aromatics. When the aim is to produce sustainable aviation fuel, one potential process pathway is by indirect liquefaction via Fischer–Tropsch synthesis. Fischer–Tropsch synthesised paraffinic kerosene plus aromatics (FT SPK/A) is a product that is fully formulated and can in principle be qualified as Jet A‐1. The synthetic jet fuel must ultimately meet all of the Jet A‐1 specifications. However, there are still hurdles on the path toward global approval of fully formulated synthetic jet fuel. In this study, several different refining pathways are shown that can be employed to produce FT SPK/A. The refining pathways have the desirable attribute of being generally useful and not limited to a specific refining technology. A case study is also presented in which FT SPK/A was produced, characterised and compared to Jet A‐1 specification requirements. It illustrated that it was practical to produce a fully formulated jet fuel via Fischer–Tropsch refining. [ABSTRACT FROM AUTHOR]

Ionomeric binders in catalyst layers, abbreviated as ionomers, play an essential role in the performance of polymer–electrolyte membrane fuel cells and electrolyzers. Due to environmental issues associated with perfluoroalkyl substances, alternative hydrocarbon ionomers have drawn substantial attention over the past few years. This review surveys literature to discuss ionomer requirements for the electrodes of fuel cells and electrolyzers, highlighting design principles of hydrocarbon ionomers to guide the development of advanced hydrocarbon ionomers. [ABSTRACT FROM AUTHOR]

Miscible gas injection (MGI) processes such as miscible CO2 flooding have been in use as attractive EOR options, especially in conventional oil reserves. Optimal design of MGI is strongly dependent on parameters such as gas-oil minimum miscibility pressure (MMP), which is normally determined through expensive and time-consuming laboratory tests. Thus, developing a fast and reliable technique to predict gas-oil MMP is inevitable. To address this issue, a smart model is developed in this paper to forecast gas-oil MMP on the basis of a feed-forward artificial neural network (FF-ANN) combined with particle swarm optimisation (PSO). The MMP of a reservoir fluid was considered as a function of reservoir temperature and the compositions of oil and injected gas in the proposed model. Results of this study indicate that reservoir temperature among the input parameters selected for the PSO-ANN has the greatest impact on MMP value. The developed PSO-ANN model was examined using experimental data, and a reasonable match was attained showing a good potential for the proposed predictive tools in estimation of gas-oil MMP. Compared with other available methods, the proposed model is capable of forecasting oil-gas MMP more accurately in wide ranges of thermodynamic and process conditions. All predictive models used other than the PSO-ANN model failed in providing a good estimate of the oil-gas MMP of the hydrocarbon mixtures in Azadegan oilfield, Iran. © 2013 Canadian Society for Chemical Engineering [ABSTRACT FROM AUTHOR]

In part I of this series the pure component PHCT-DNSK equation of state (EOS) was presented. In this paper the EOS is extended to describe mixtures, particularly asymmetric mixtures containing one or more low molecular weight spherical compound together with one or more high molecular weight chain-like compound. The EOS utilises theoretically correct mixing rules and is generally able to predict the correct trends quantitatively for binary mixtures, and in most cases outperform other EOSs. With the use of a small, temperature independent, interaction parameter the EOS is able to predict the phase behaviour of the investigated systems qualitatively. The EOS is able to predict the phase behaviour of a multi-component system containing one or more light components and a range of heavy hydrocarbons with improved accuracy compared to other EOSs at reduced computational times. © 2011 Canadian Society for Chemical Engineering [ABSTRACT FROM AUTHOR]

Thermodiffusion has an important role in displacements of hydrocarbon reservoir. The ratio of the evaporation energy to the activation energy of viscous flow in pure limits, τpure, k, is of a great importance in estimating the thermodiffusion coefficient for non-associating fluid mixtures. Several methods may be used to estimate τpure, k which causes different values for thermodiffusion coefficients. A fixed value for τpure, k was considered to predict the thermodiffusion coefficient. In this paper, Abbasi et al.'s [J. Non-Equilib. Thermodyn. 2010;35:1-14] model and Shukla and Firoozabadi's model have been applied to predict thermodiffusion coefficients for linear chain hydrocarbon binary mixtures. The results show a very good performance of the simple approach in respect to the previous models in estimating thermodiffusion coefficients. © 2011 Canadian Society for Chemical Engineering [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Chemical Engineering is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• This paper investigates the dependence of monoterpene emissions at the canopy scale on total leaf area and leaf distribution. Simulations were carried out for a range of hypothetical but realistic forest canopies of the evergreen Quercus ilex (holm oak). • Two emission models were applied that either did (SIM-BIM2) or did not (G93) account for cumulative responses to temperature and light. Both were embedded into a canopy model that considered spatial and temporal variations of foliage properties. This canopy model was coupled to a canopy climate model (CANOAK) to determine the micrometeorological conditions at the leaf scale. • Structural properties considerably impacted monoterpene emission. The sensitivities to changes in total leaf area and to leaf area distribution were found to be of similar magnitude. The two different models performed similarly on a whole-year basis but showed clear differences during certain episodes. • The analysis showed that structural indices have to be carefully evaluated for proper scaling of emission from leaves to canopy. Further research is encouraged on seasonal dynamics of emission potentials. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Chemical Engineering is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Chemical Engineering is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The high‐quality hydrocarbon source rocks developed in the Longtan Formation of the Qijiang area and the good reservoir capacity of the overlying dolomite of the Jialingjiang Formation indicate that the area has great exploration potential. To clarify the hydrocarbon migration and accumulation characteristics of the area, the fluid potential of the Longtan Formation in the Qijiang area in the Early Jurassic was determined. The direction of the maximum negative gradient of the fluid potential indicates the direction of the primary migration of hydrocarbons, and the structural ridge theory is used to analyse the direction of the secondary migration of hydrocarbons. The results show that the fluid potential of the hydrocarbon source rocks of the Longtan Formation in the Early Jurassic is characterized by the alternate distribution of high potential zones and low‐potential zones. The central syncline, eastern syncline and western syncline are drainage zones and high potential zones, while the Shiyougou structural belt and Fo'er Ya structural belt are supply zones and low‐potential zones. The oil and gas fluids migrate from the east–west direction to the anticlinal zone for the primary migration; the structural ridge controls the secondary migration of oil and gas in the low‐potential area along the north–south direction, resulting in a zonal distribution of oil and gas traps along the structural ridge. By combining fluid potential and structural ridge characteristics to determine the dominant direction of primary and secondary hydrocarbon migration, a model of hydrocarbon migration and accumulation in the Qijiang area is developed, which provides an important basis for finding hydrocarbon reservoirs. [ABSTRACT FROM AUTHOR]

The construction of 1,2‐position‐connected azulene oligomers was achieved. In the crystal packing structure of the terazulene, two molecules of (Ra)‐ and (Sa)‐configurations formed a pair. Variable temperature NMR measurements and theoretical calculations of the quaterazulene suggest that the helical and syn‐type structure with terminal azulene overlap is more stable. Two kinds of fused terazulenes (1,2′′‐closed and 1,8′′‐closed) were also synthesized by intramolecular Pd‐catalyzed C−H/C−Br arylation of the terazulene moieties. X‐ray structure analysis of 1,2′′‐closed terazulene revealed a planar structure, while an analysis of 1,8′′‐closed terazulene performed on a C60 co‐crystal revealed a curved structure forming a 1 : 1 complex covering the co‐crystal. Nucleus‐independent chemical shift (NICS) calculations carried out for the central seven‐membered ring of 1,8′′‐closed terazulene showed a positive value, suggesting anti‐aromatic properties. [ABSTRACT FROM AUTHOR]

An α-L-rhamnosidase from the seeds of Fagopyrum esculentum (saracen corn) has previously been identified, and the effect of the enzyme on rhamnosic bonds has been studied with various flavonoid glycosides. This α-L-rhamnosidase can be useful in structural studies, and a preliminary report of this study has appeared. The present paper describes the extensive purification of the enzyme and the determination of its properties. The purification involved extraction, ammonium sulfate fractionation and chromatography on Sephadex G 75, DEAE-Sephadex and Ultrogel AcA-44. The α-L-rhamnosidase was purified about 9600 fold and the final enzyme preparation was practically pure according to the criteria of disc electrophoresis. The molecular weight of this α-L-rhamnosidase, calculated from data obtained by disc gel electrophoresis and gel filtration, was about 70000. Isoelectric focusing established the isoelectric point to be 3.7. The behaviour of the enzyme on a concanavalin-A-Sepharose column suggests the presence of residues resembling α-D-mannose or α-D-glucose in the protein. The various kinetic parameters, Kcat, Km and the Kcat/Km ratio have been determined at pH 5 on the following substrates: p-nitrophenyl-α-L-rhamnoside and rutinose (6-O-α-L-rhamnosyl-D-glucopyranose). All kinetics exhibit a Michaelian behaviour and the Km for the former substrate was 0.33 mM and for the latter, 2.2 raM. The Kcat/Km ratio corroborates the greater specificity of the enzyme for p-nitrophenyl-α-L-rhamnoside. L-Rhamnose, L-lyxose, 6-deoxy-D-glucose and methyl-α-D-mannoside were shown to behave strictly as competitive inhibitors of α-L-rhamnosidase activity; it seems that the methyl group of L-rhamnose is important for substrate binding to the enzyme. [ABSTRACT FROM AUTHOR]

Earlier investigations had shown that the C-methyl group at C-3 of L-mycarose (2,6-dideoxy- 3-C-methyl-L-ribo-hexose) originates from the S-methyl group of L-methionine. In the present paper the question was investigated whether this methylation involves transfer of the intact methyl group. A tylosin producing strain of Streptomyces [radiae was grown in the presence of L-[methyl-14C]- methionine and D,L-[methyl-2H3]methionine. The dilution value of 14C into mycarose isolated from tylosin after 6 days of fermentation was 1.47. Mycarose was converted to its 1-ethylthio- glycoside. In the mass spectrum of the latter compound the molecular ion and all fragment ions which contain the branched C-methyl group had additional peaks of 3 mass units higher than the corresponding peaks of the unlabeled thioacetal. From the peak intensities the amount of trideuterated species present was calculated to be 31 ± 3%. Molecular species with one or two deuterium atoms were present to less than 3%. The structure of the fragment ions was confirmed by high resolution mass spectrometry. The results prove that methylation had taken place with transfer of the intact methyl group of methionine to C-3 of the hexose chain. [ABSTRACT FROM AUTHOR]

A carbon layer deposited on an optical component is the result of complex interactions between the optical surface, adsorbed hydrocarbons, photons and secondary electrons (photoelectrons generated on the surface of optical elements). In the present study a synchrotron-induced contamination layer on a 340 mm × 60 mm Au-coated toroidal mirror has been characterized. The contamination layer showed a strong variation in structural properties from the centre of the mirror to the edge region (along the long dimension of the mirror) due to the Gaussian distribution of the incident photon beam intensity/power on the mirror surface. Raman scattering measurements were carried out at 12 equidistant (25 mm) locations along the length of the mirror. The surface contamination layer that formed on the Au surface was observed to be hydrogenated amorphous carbon film in nature. The effects of the synchrotron beam intensity/power distribution on the structural properties of the contamination layer are discussed. The I(D)/ I(G) ratio, cluster size and disordering were found to increase whereas the sp2: sp3 ratio, G peak position and H content decreased with photon dose. The structural parameters of the contamination layer in the central region were estimated (thickness ≃ 400 Å, roughness ≃ 60 Å, density ≃ 72% of bulk graphitic carbon density) by soft X-ray reflectivity measurements. The amorphous nature of the layer in the central region was observed by grazing-incidence X-ray diffraction. [ABSTRACT FROM AUTHOR]

The Neogene petroleum system in the Yiliping area of the Qaidam Basin presents great prospects for natural gas exploration. However, its natural gas potential, including the source rock characteristics, is insufficient. Due to a lack of geological constraints, the hydrocarbon generation and expulsion (HGE) model, which is widely used in resource potential evaluation, may be unable to obtain optimal parameters. Here, we propose an improved HGE model based on least‐squares Monte Carlo to assess the HGE characteristics and natural gas resource potential of the Neogene source rocks in the Yiliping area by combining geological and geochemical investigations. The findings show that the Neogene source rock is effective and has significant potential for natural gas generation. Algae and bacteria, which were deposited in a saline and anoxic environment, are the primary sources of organic matter in Neogene source rock (primarily Type II and Type III). Modelling work suggests that Type II and III kerogen of Neogene source rock reach hydrocarbon generation threshold (HGT) at Ro = 0.38% and Ro = 0.49% and reach hydrocarbon expulsion threshold (HET) at Ro = 0.45% and Ro = 0.55%. The maximum HGE intensities are 3400 × 104 and 3378 × 104 t/km2. The extra‐source natural gas and shale gas resource potentials are predicted to be 2.05 × 1012 m3 to 4.11 × 1012 m3 and 7.03 × 1012 m3. The findings will guide future Neogene natural gas exploration in the Yiliping area of the Qaidam Basin. [ABSTRACT FROM AUTHOR]

Efficiency is a crucial factor for power cycles. Generally, in the same temperature range, the cycle efficiency for a basic organic Rankine cycle (ORC) is higher than a similar trilateral flash cycle (TFC) for almost all working fluids and heat source/heat sink temperature pairs. According to some recent results, by using super dry working fluids, the thermal efficiency of TFC can outperform its ORC counterpart at high temperatures. This study performed the thermodynamics analysis using three dry working fluids with subcritical basic ORC and TFC with zero to partial recuperated heat ratio. The results showed that using recuperative heat exchange effectively contributes to increasing the efficiency of ORC and TFC. However, the rate of efficiency increase in ORC is higher than the TFC, which can be clearly seen, especially at high maximal cycle temperatures. Using super dry working fluids, the recuperator‐free TFC has favorable cycle efficiency at high heat source temperatures. In contrast, by adding heat recovery for both systems, the ORC can outperform the TFC at 0.4, 0.2, and 0.1 recuperated heat effectiveness for Dodecane, Decane, and Nonane, respectively. [ABSTRACT FROM AUTHOR]

An Extensive Literature Search (ELS) to collect and identify all studies published since 2010 and relevant to the topic mineral oil hydrocarbons in combination with the substance group characterisation, occurrence in food and toxicity was performed in the three databases PubMed, Web of Science and SciFinder® for six Areas. After combination of the searches from the three databases and removal of the duplicates, the total number of references is 2504. The evaluation of all retrieved references for relevance by screening the title and abstract and applying eligibility criteria (inclusion/exclusion) resulted in a total number of relevant references for Area 1 of 55, for Area 2 of 27, for Area 3 of 15, for Area 4 of 21 for Area 5 of 1 and for Area 6 of 6. The total number of relevant references was 93. However, for the substance group POH no relevant reference was identified. Additionally, there are 4 references additionally, which could not be clearly assigned. [ABSTRACT FROM AUTHOR]

Structural mapping and fieldwork in the Lesser and Higher Himalayan sequences in the western Arunachal Himalaya reveal crucial deformation fabrics in the Main Central Thrust (MCT) and Dirang Thrust (DT) zones. The top‐to‐SW ductile shear in the MCT and DT zones is correlated with the swing in the trend of MCT and DT from NE to NNW. The curved MCT and DT as traced by previous authors on the regional map of Arunachal Himalaya are studied. It is found that at places where these faults swing, shear senses developed at the meso‐scale. These shear senses are studied in meso‐ and micro‐scales. Seismicity in the western Arunachal Himalaya is influenced by basement cross‐strike crustal‐scale NW‐trending buried Bomdila Fault (BF). Landslides occur frequently along the Bhalukpong‐Bomdila–Sela traverse are also linked with the transverse BF. In its southern part, the BF coincides with the Dhansiri Lineament and is the basin margin fault in the upper Assam shelf. The Gondwana sediments extended further south below the Brahmaputra alluvium along the fault is to be explored for hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

Reliability is a significant performance index for any electrical equipment in the industry, especially for electric motor driven (EMD) systems. Modelling the reliability of an EMD system is a difficult and challenging task. However, based on field data, the dominant failure modes of some motor system parts can be used to develop a simple and credible reliability model. This study proposes a failure rate prediction model for an EMD system that is currently in use in hydrocarbon industries. In addition, a fault tree model was designed to identify the root causes of the failures and the failure mechanism of the most dominates failure modes in EMD systems. To accomplish the study's objectives, an existing failure databank of over 100 failures of EMD systems was collected and surveyed from the field. The historical information and failure rate models that were collected for the electric motors are investigated and used to model the prediction model of the EMD system. Three competing failure modes were found to dominate motor life: bearing failures, winding failures and shaft failures. A mathematical model for each of these failure modes with dominant variables is developed, and a risk failure model is established. [ABSTRACT FROM AUTHOR]

The present investigation is the first to provide information on the formation, process and influence factors for hydrocarbon generation and expulsion potential of the Cuizhuang Formation source rock in the Yuncheng sub‐basin to decipher the reason why no commercial petroleum resources have been found so far. In this study, data from the Jitan‐1 well in the Yuncheng sub‐basin were applied for the Cuizhuang Formation source rock basin modelling and organic geochemical analyses to reconstruct the burial and thermal evolution history and reveal the timing and process of hydrocarbon generation and expulsion. The modelling results indicate that the peak palaeotemperature of the Cuizhuang Formation source rock reached ~205°C in the Middle Carboniferous (~327 Ma) at a maximum burial depth of ~4000 m, when rapid burial subsidence and thermal events played a significant role in increasing thermal maturity. The Cuizhuang Formation generated and expelled small amounts of hydrocarbons from the Early Ordovician until the Middle Carboniferous, starting with the primary kerogen cracking and conversion to oil from the Early to Middle Ordovician (~476–461 Ma), corresponding to the thermal maturity values of 0.55–0.70 %VRo and transformation ratio (TR) <10%. The expulsion of most generated oil (0.70–1.30 %VRo, TR of 10%–90%) started from the Middle Ordovician to the Early Carboniferous (~461–351 Ma), before reaching the secondary cracking of the retained oil into gas (>1.30 %VRo and TR of 90%–100%) from the Early to Middle Carboniferous (~351–327 Ma). Destruction of the initial formation of hydrocarbon reservoirs in the Yuncheng sub‐basin was primarily controlled by the Middle Carboniferous tectonic event with its major uplift‐erosion, resulting in the absence of potential hydrocarbon reservoirs in recent exploration activities in some parts of the Yuncheng sub‐basin. [ABSTRACT FROM AUTHOR]

Morphological characterization was investigated by agro‐morphological criteria related to carob seed size in four different moroccan regions collected in 2018 and 2019. There was no significant difference (p ≤ 0.05) on the seeds lengths and widths. However, a significant difference between seeds thickness and total seeds weight per pod (p ≤ 0.05) were observed between these four populations. The fatty acid, sterol, tocopherol, hydrocarbon, and the unoxygenated composition of carob seed extracts (Ceratonia siliqua L.) were studied. The mean fat yield of the seeds obtained is 1.53%–2.17%, 2.14%–2.15%, 1.61%–1.62%, 1.71%–1.75% for, respectively, the P1 (Meknes), P2 (Fez), P3 (Khemisset), and P4 (Marrakech) in 2018 and 2019. The seed oil was extracted with hexane and the analysis of the fatty fraction was performed by gas chromatography–mass spectrometry (GC–MS). Results show that the major fatty acids for 2018 and 2019 are linoleic acid (61.48%–61.52%, 52.12%–52.14%, 57.76%–58.15%, 61.33%–61.52%), palmitic acid (15.78%–15.81%, 16.44%–16.45%, 19.11%–18.37%, 20.24%–20.32%), oleic acid (11.03%–11.04%, 8.72%–8.82%, 8.51%–8.61%, 8.41%–8.53%), stearic acid (4.35%–3.14%, 5.40%–5.43%, 3.12%–3.13%, 0.96%–1.56%), and cerotic acid (0.62%–0.53%, 4.51%–4.52%, 4.03%–4.06%, 3.84%–3.87%). The unsaturated fatty acids (69.39% in 2018 and 69.68% in 2019) are the most dominant in the four seed extracts compared to the saturated fatty acids. In addition, the oil carob seeds analysis revealed the presence of γ‐tocopherol, α‐tocopherol and four sterols that included campesterol, stigmasterol, and β‐sitosterol. Moreover, the determination of hydrocarbon and un‐oxygenated compounds confirmed the existence of major compounds such as heptadecane, 2‐methyltriacontane, 1‐iodo hexadecane and 1‐iodo octadecane. The hierarchical analysis based on the morphological and chromatographic characterization of the seeds allowed the identification of three groups. Consequently, the first group consisted of populations from Marrakesh (P4) and Khemisset (P3), the second group consisted of the P1 from Meknes, and the P2 from Fez constituted the third group. [ABSTRACT FROM AUTHOR]

Organismal traits may experience conflicting selection pressures if they fulfil different functions simultaneously. This can require trade‐offs between functions or alternatively functional separation between elements of the trait.An important multifunctional trait in insects is the cuticular hydrocarbon (CHC) layer. CHCs cover the body of nearly all insects, protect against desiccation and serve as a communication signal. In social insects like ants, they provide cues for nestmate recognition. To maintain their waterproofing function, insects have to adjust CHC composition to current temperatures. These changes might affect information content and interfere with communication, which would be especially detrimental in social insects.Here, we studied how acclimation affects nestmate recognition in two sister species of the ant genus Lasius. Colony fragments were exposed to three climate regimes. We analysed behaviour towards same and differently acclimated conspecifics, and determined which CHCs were related to acclimatory changes, colony differences and inter‐individual aggression.Differential acclimation led to higher aggression and chemical distances among former nestmates. We identified small CHC subsets, which only differed among colonies or among acclimation treatments. Moreover, few compounds sufficed to explain inter‐individual aggression, suggesting that ants do not use the entire CHC profile for nestmate recognition and that colony identity is encoded in a redundant way.Across individual CHCs, their contribution to colony differences and to differences among acclimatory treatments was negatively correlated, indicating that there is some degree of functional separation. However, CHC classes could not be clearly assigned to one or another function, indicating that the role of each CHC is idiosyncratic and may differ among species. Acclimatory effects and colony differences were more independent from each other in L. platythorax than in L. niger, indicating that functional separation can differ even among sister species.Our results show that CHC functions are more intertwined than previously assumed, suggesting that insects cannot optimise all functions independently. The main constraint might be the need to maintain a certain phase behaviour of the CHC layer, which depends on CHC composition and affects functionality. The need to separate functions might depend on species‐specific ecological and life‐history parameters.Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Sab'atayn Basin is considered to be the most petroliferous Mesozoic basin in Yemen, although exploration efforts in the northwestern part of the basin are unproven due to scant drilling activities. In this work one‐dimensional (1D) basin modelling was used to examine the hydrocarbon generation and expulsion history of the Upper Jurassic source rocks using PetroMod2012.2 software. The geo‐history modelling was applied for the studied wells, and it shows that some stratigraphic units are missing, which adversely affect the tectonics, sedimentary subsidence, burial history, hydrocarbon maturation, and generation. There is a major period of subsidence that occurred in the Upper Jurassic and is manifest in the Kamaran‐01 well. In addition, a second major uplift occurred in the Miocene and had a discernible effect on heat flow distribution as well as burial histories. Reverse heat flow is observed in the Saba‐01 well, where the present heat flow is greater than the palaeo‐heat flow. The beginning of petroleum generation in the Meem and Lam members (Madbi Formation) source units has been predicted to occur during the Late Jurassic, and subsequently occurred in the Lower Cretaceous. Peak expulsion of hydrocarbons from the Meem Member occurred in the Eocene and late Oligocene, while expulsion modelling performed on the Lam Member asserts that it has not reached the phase of oil expulsion. [ABSTRACT FROM AUTHOR]

Oil in an unconventional tight reservoir is considered to migrate from a very adjacent reservoir or be impregnated in situ within source rocks, but their large hydrocarbon molecular fractions during short‐distance migration in the tight system are poorly understood. In order to explore the evolution characteristics and differences of the geochemical properties, especially the biomarkers, between expelled oil (just detached from source rock and not undergoing long‐distance migration) and retained oil under different thermal evolution stages of lacustrine marlstone. Semi‐open hydrous pyrolysis was conducted on an immature lacustrine marlstone collected from the third member of the Eocene Shahejie Formation in Shulu Sag, Bohai Bay Basin and the hydrocarbon product expelled from and remained in the rock during pyrolysis were collected and analysed with gas chromatography–mass spectrum instrument. The results indicate that the saturates compositions show expelled oil having commonly lower thermal maturity than retained oil because expelled oil is a mixture of multiple‐term hydrocarbon expulsions, while retained oil is the remained final hydrocarbon product of pyrolysis in semi‐open experimental system. The hydrocarbon migration has a significant effect on the maturity‐related parameters distribution such as 20S/(20S + 20R) and αββ/(αββ + ααα) for C29 steranes. Hydrocarbon expulsion enables Ts/(Ts + Tm) ratio in expelled oil is much greater than that of retained oil at lower matural stage. The saturated hydrocarbon maturity biomarkers in retained oil and expelled oil vary in a subtly different pathways with increasing maturity, comparatively the aromatic hydrocarbon biomarkers, such as triaromatic steroids and methyl‐phenanthrene (MPI1 and MPI2), regularly changed during maturation, which is not obviously affected by migration effects and can be used not only for thermal maturity predications but also for oil–oil or oil–source correlation. C29 20S/(20S + 20R) and C29 αββ/(αββ + ααα) commonly are preferable maturity parameters for shale or mudstone, reflecting that mineral matrix and oil in source rock are not affected by migration and supposed to have an oil thermal maturity corresponding to depth. Combined with some tight reservoir cases in North America and China, the biomarker ratios variation along depth and its abnormal value can be used to predict sweet spots in tight reservoirs. [ABSTRACT FROM AUTHOR]

The unconventional reserves are vital future energy resources and globally augmented interest endeavours the discovery of gas and oil‐rich shales. The Kommugudem Formation, Krishna Godavari Basin was evaluated based on sample laboratory and well log studies from six wells deciphering mineralogical and organic geochemical parameters to provide an understanding of hydrocarbon potential and brittleness. Kommugudem Formation constitutes Type III kerogen dominantly with high total organic carbon (TOC) and Tmax indicating the presence of high organic matter. The mean vitrinite reflectance indicates mature to post‐mature shale majorly in the gas generation window. Fourier transform infrared spectroscopy functional group investigation revealed the presence of aromatics and aliphatics with a higher degree of abundance owing to higher TOC content. The basic well logs recorded in the studied region are used to estimate the continuous TOC and porosity of the formation and corroborate with laboratory core data. Petrographic, X‐ray diffraction, and field emission scanning electron microscopy studies revealed the presence of dominantly siliceous mineral matter with relatively lower clay and carbonates. Organic mudstone classification indicates formation is dominantly silica‐dominated lithotype and clay‐rich siliceous mudstone. Microfractures and micropores are observed in mineral and organic matter that may act as storage sites for hydrocarbons. Kommugudem Formation on the basis of mineralogy indicates compositional analogy with brittle zones of Barnett Shale Formation. The high mineralogical brittleness index of the Kommugudem Formation indicates good conditions for hydraulic fracturing. The present investigation demonstrates excellent hydrocarbon generation potential and good brittleness in wells A and B while C, D, E, and F have relatively lower potential and may have low gas and oil sources. [ABSTRACT FROM AUTHOR]

Background and Purpose: Ilexgenin A is a triterpenoid from ShanLv Cha with beneficial effects on metabolic homeostasis. We investigated whether ilexgenin A could inhibit hepatic de novo fatty acid synthesis via the interfering with SREBP1 maturation.Experimental Approach: The effects of Ilexgenin A on CRTC2 translocation and SREBP1 maturation were investigated in the liver of fasted mice and hepatocytes exposed to saturated fatty acids. The effect of Iilexgenin A on hepatic lipid accumulation was also observed in high-fat diet fed mice.Key Results: Sec23A and Sec31A are two subunits of COPII complex and their interaction is essential for the processing of SREBP1 maturation. Ilexgenin A activates AMPK by reducing cellular energy and preventing cytoplasmic CRTC2 to compete with Sec23A for binding to Sec31A under nutrient-rich conditions. Consequently, ilexgenin A impaired COPII-dependent SREBP1 maturation via disrupting Sec31A-Sec23A interaction, leading to the inhibition of de novo fatty acid synthesis in the liver. In contrast, mTORC1 phosphorylated Ser136 of CRTC2, facilitating the formation of Sec31A-Sec23A interaction to promote SREBP1 maturation, whereas this action was reversed by ilexgenin A in an AMPK-dependent manner. Ilexgenin A protected CRTC2 function and restrained hepatic lipogenic response in high fat diet-fed mice, providing in vivo evidence to support the beneficial effects of ilexgenin A on lipid metabolism.Conclusions and Implications: Ilexgenin A activated AMPK and restrained CRTC2 to the cytoplasm to prevent SREBP1 maturation via impairing COPII function in the liver. This suggests that CRTC2 might be a potential target for pharmacological intervention to prevent hepatic lipid deposition.Linked Articles: This article is part of a themed issue on Preclinical Models for Cardiovascular disease research (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.5/issuetoc. [ABSTRACT FROM AUTHOR]

The oxidation of NO, CO and hydrocarbons (HC) individually, in mixtures, and with NO2 were investigated over a monolith-supported Pt/Al2O3 catalyst under oxidising conditions. Although competitive adsorption and inhibition by other species on oxidation reactions is a relatively well-known phenomenon, this study represents a more comprehensive examination of such effects between key components in vehicle exhaust gases. NO2 was completely reduced by CO and C3H6, under NO2 limited conditions, at temperatures as low as 110°C and at temperatures above 140°C with dodecane and m-xylene. NO2 was then again observed once the extent of oxidation of the other species by oxygen was significant. Under the conditions tested, NO, CO and HC oxidation was inhibited by NO2 in the feed gas mixture. HC were also found to inhibit the oxidation of NO and other HC species due to site adsorption competition. For CO, HC did not change the onset of oxidation, but did inhibit the extent after their light off began. At low temperatures, CO was initially found to inhibit NO oxidation, but at higher temperatures, once CO oxidation was significant, CO promoted NO conversion to NO2. The observed inhibition effects of the different gases on HC oxidation were not additive, indicating one species would cause inhibition, but once its inhibition ended, another species could still then cause inhibition. The combined effect of C3H6, NO and NO2 on CO conversion was found to be additive. This is because CO oxidation started prior C3H6. © 2011 Canadian Society for Chemical Engineering [ABSTRACT FROM AUTHOR]