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To determine the occurrence of mineral oil hydrocarbons (MOH) in food contact papers in China, and to investigate the potential sources of MOH contamination, a total of 159 food contact papers and raw materials were analysed by off-line solid-phase extraction-gas chromatography flame ionisation detection (SPE-GC-FID) and a GC-MS method. The migration of MOH from food contact papers into Tenax, olive oil or 50% ethanol under the worst foreseeable conditions of use was determined. The results indicated that the occurrence of MOH in China is of a potential health risk concerning the migration of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) which were detected in 82.6% and 50.4% of samples, respectively. Migration of MOSH from 47.9% of samples was higher than 2 mg/kg and migration of MOAH from 32.2% samples exceeded 0.5 mg/kg in case of the worst foreseeable condition of use. The highest mean migration of MOSH and MOAH were found in packaging papers for long-term storage (more than 6 months), with mean migration of 91.2 mg/kg and 1.4 mg/kg, respectively. Migration of MOH from printed paper was considerably higher than that of unprinted paper, validating previous findings that the printing ink is the predominant source of MOH contamination in food contact papers. Migration of MOH from paper bowls used for packing instant noodles was relatively low, suggesting the internal hollow layer may be acting as a functional barrier that could block the transfer of MOH (up to C28) through the gas phrase, even though the outer layer was made from recycled paper. High concentrations of MOSH and MOAH were also detected in de-foamers, adhesives and rosin sizing agents, indicating that the MOH contamination caused by the use of raw materials and additives should also be taken into consideration. [ABSTRACT FROM AUTHOR]

Mineral oil hydrocarbons (MOH) are widely used in the food industry for applications such as printing inks, additives, adhesives, and processing aids for food additives. Recently, the migration of MOH from food contact paper and board into foods has raised public health concerns. In this study, a total of 110 food contact paper and board samples, including baking and cooking paper (23), baking cups (28), food packaging bags (22), lunch boxes (8), party plates (26), and straws (3) were evaluated to quantify the content and short-term migration levels of MOH. The MOH were separated into mineral oil saturated hydrocarbons (MOSH)/polyolefin oligomeric saturated hydrocarbons (POSH) and mineral oil aromatic hydrocarbons (MOAH) via a validated on-line liquid chromatography−gas chromatography−flame ionisation detection (LC–GC–FID) technique. The coating materials of the sample products comprised polyethylene, polypropylene, polyethylene terephthalate, and silicone. The effects of the coating materials on the content and migration of MOH/POSH were evaluated. Quantitative analysis of the MOH in the samples showed that the MOSH/POSH and MOAH content varied widely, ranging from 16 to 5626 mg kg−1 for MOH, regardless of the coating materials. Short-term migration of MOSH/POSH was observed only in samples with polyolefinic coatings, such as polyethylene and polypropylene, in experiments conducted at 25 °C for 10 min, although the extent of MOAH migration for all samples was at the trace level. The migration of MOSH/POSH was detected within the range of 0.93 to 62.3 μg L−1 in 22 samples, and the migration of MOAH was detected within the range of 0.80 to 2.6 μg L−1 in only 4 samples. These results demonstrate that although the short-term migration potential of MOH is generally negligible, the migration of MOSH/POSH into wet fatty foods can be accelerated by polyolefinic coatings, even within a very short time. [ABSTRACT FROM AUTHOR]

This paper explores the unintentional contamination of Surface-Enhanced Raman Scattering (SERS) substrates by ambient hydrocarbon contaminants and their contribution to SERS spectra. Previous studies have identified amorphous carbon as a potential complicating factor in data analysis in SERS experiments, although its origin has been elusive. Our work showed that ambient hydrocarbon contamination and its decomposition products can be detected by SERS on a gold substrate. We propose that ambient air itself is a source of amorphous carbon contamination on SERS substrates. This understanding is crucial for the correct interpretation of SERS data and highlights the need for careful consideration of potential environmental contaminants in SERS analysis. [ABSTRACT FROM AUTHOR]

We report the unprecedented electrocatalytic activity of a series of molecular nickel thiolate complexes (1–5) in reducing CO2 to C1–3 hydrocarbons on carbon paper in pH‐neutral aqueous solutions. Ni(mpo)2 (3, mpo=2‐mercaptopyridyl‐N‐oxide), Ni(pyS)3− (4, pyS=2‐mercaptopyridine), and Ni(mp)2− (5, mp=2‐mercaptophenolate) were found to generate C3 products from CO2 for the first time in molecular complex. Compound 5 exhibits Faradaic efficiencies (FEs) of 10.6 %, 7.2 %, 8.2 % for C1, C2, C3 hydrocarbons respectively at −1.0 V versus the reversible hydrogen electrode. Addition of CO to the system significantly promotes the FEC1–C3 to 41.1 %, suggesting that a key Ni−CO intermediate is associated with catalysis. A variety of spectroscopies have been performed to show that the structures of nickel complexes remain intact during CO2 reduction. [ABSTRACT FROM AUTHOR]

We report the unprecedented electrocatalytic activity of a series of molecular nickel thiolate complexes (1–5) in reducing CO2 to C1–3 hydrocarbons on carbon paper in pH‐neutral aqueous solutions. Ni(mpo)2 (3, mpo=2‐mercaptopyridyl‐N‐oxide), Ni(pyS)3− (4, pyS=2‐mercaptopyridine), and Ni(mp)2− (5, mp=2‐mercaptophenolate) were found to generate C3 products from CO2 for the first time in molecular complex. Compound 5 exhibits Faradaic efficiencies (FEs) of 10.6 %, 7.2 %, 8.2 % for C1, C2, C3 hydrocarbons respectively at −1.0 V versus the reversible hydrogen electrode. Addition of CO to the system significantly promotes the FEC1–C3 to 41.1 %, suggesting that a key Ni−CO intermediate is associated with catalysis. A variety of spectroscopies have been performed to show that the structures of nickel complexes remain intact during CO2 reduction. [ABSTRACT FROM AUTHOR]

The occurrence of mineral oil hydrocarbons (MOH) in cellulose-based packaging is mainly due to the offset printing process where MOH are used as a ink pigments' solvent. The MOH migration from paper/paperboard to food is matter of concern for EFSA, members state authorities, consumers, and food industry. In this study, the feasibility to stabilize MOH by adding a sorbent into recycled paper obtained through a common washing process was investigated and the migration to wheat flour/Tenax assessed. Among several white/pale yellow porous materials, organo-modified powder silica MCM-41-Si(CH) showed the best combination between affinity for MOH (184% dw) and stability to thermal regeneration. A freshly issued newspaper with >3000 mg MOH kg was used to produce recycled paper at a laboratory-scale plant. MCM-41-Si(CH) was added at the pulping step (1% dw) and the sorbent-enriched pulp handled according to a washing paper production process with no effect on the paper optical brightness. The MOH content of the wheat flour in contact with the sorbent-enriched paper under accelerated migration conditions (15 days at 40 °C) resulted 20% of that contacted with control paper (4.3 ± 1.1 and 20.4 ± 5.5 mg kg, respectively), despite its contamination was 24% higher than the control. On the contrary, Tenax contamination resulted 56.0 ± 10.0 and 47 ± 14.0 mg kg when exposed to sorbent-enriched and control paper, respectively. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Stepwise pyrolysis at 350 and 500 °C can separate products into two fractions. • First step liquid product was acidic and had high amounts of oxygenated compounds. • Products from the second step had high hydrocarbon contents and low acidity. • Interaction between cellulose and plastics during stepwise pyrolysis was observed. • Test on real wastes and discussion of scaling-up possibilities were presented. Abstract Mixed plastics and papers are two of the main fractions in municipal solid waste which is a critical environmental issue today. Recovering energy and chemicals from this waste stream by pyrolysis is one of the favorable options to achieve a circular economy. While pyrolysis products from plastics are mainly hydrocarbons, pyrolysis products from paper/biomass are highly oxygenated. The different nature of the two pyrolysis products results in different treatments and applications as well as economic values. Therefore, separation of these two products by multi-step pyrolysis based on their different decomposition temperatures could be beneficial for downstream processes to recover materials, chemicals and/or energy. In this work, stepwise pyrolysis of mixed plastics and paper waste was performed in a batch type fixed bed reactor using two different pyrolysis temperatures. Neat plastic materials (polystyrene, polyethylene) and cellulose mixtures were used as starting materials. Then, the same conditions were applied to a mixed plastics and paper residue stream derived from paper recycling process. The condensable products were analyzed by GC/MS. It was found that pyrolysis temperatures during the first and second step of 350 and 500 °C resulted in a better separation of the oxygenated and hydrocarbon condensates than when a lower pyrolysis temperature (300 °C) was used in the first step. The products from the first step were derived from cellulose with some heavy fraction of styrene oligomers, while the products from the second step were mainly hydrocarbons derived from polystyrene and polyethylene. This thus shows that stepwise pyrolysis can separate the products from these materials, although with some degree of overlapping products. Indications of interaction between PS and cellulose during stepwise pyrolysis were observed including an increase in char yield, a decrease in liquid yield from the first temperature step and changes in liquid composition, compared to stepwise pyrolysis of the two materials separately. A longer vapor residence time in the second step was found to help reducing the amount of wax derived from polyethylene. Results from stepwise pyrolysis of a real waste showed that oxygenated and acidic products were concentrated in the liquid from the first step, while the product from the second step contained a high portion of hydrocarbons and had a low acid number. [ABSTRACT FROM AUTHOR]

Piping is an essential component of processing plants that transfers process fluids from one piece of equipment to another. To detect the unpredictable deterioration of piping systems, periodic or continuous pipe inspection for wall loss is conducted, which determines when preventative or corrective maintenance activities, usually replacements, should be done. Therefore, it is necessary to develop an optimal maintenance strategy to replace piping systems to reduce the overall maintenance expenditure and avert the effects of pipe failure. Most of the literature in this field concentrates on maintenance activities executed during decision-making. This paper investigates creating a system and tool to assist decision-makers in evaluating and selecting the optimal moment to replace a deteriorating pipe based on the current state of the piping system. Considering that preventative replacement of the pipeline is done during a scheduled shutdown, also referred to as a turnaround, this paper investigates making a preventative replacement ruling two turnaround cycles ahead. We account for the varying thickness at different monitoring locations of two piping systems in a refinery by applying a nonstationary gamma process with random effects. We employ the Markov decision process (MDP) and the value iteration algorithm to determine the most effective maintenance replacement policy. The outcome of our analysis is an optimal maintenance policy that minimizes the cost of maintenance. Practical Applications: This paper's practical use is to aid in maintenance planning in refineries, midstream or pipelines, chemical plants, and gas facilities by planning piping replacement in two shut-down cycles ahead of time. The pipe wall is classified into states ranging from the present thickness reading to the retirement thickness. The likelihood of transiting from one state to another is calculated based on the corrosion rate. Given that the pipe wall thickness is classified into states, the current wall thickness, transitional probabilities, and preventative and corrective maintenance costs, including lost profit opportunity, can be inputted into the model to help decision-makers decide if it is optimal to replace the piping in the subsequent two shut-down cycles. This policy will assist in reducing the risk of a pipe failure, which has financial, safety, and environmental consequences. It is also critical not to replace a still-in-good-shape pipe. This model may be customized to pipe systems in the various petrochemical sectors with known retirement thicknesses to estimate the risk of operating near the retirement thickness. [ABSTRACT FROM AUTHOR]

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]

Abstract: A papermaking technique with a dual polyelectrolyte retention system was used for the preparation of NaY zeolite-containing papers, which implied the use of cationic and anionic polymers. Two kinds of fibers were employed, either cellulosic or ceramic ones, and accordingly papers with different characteristics were obtained: those that only contained cellulosic fibers for low temperature applications, cellulosic papers, and those prepared using both cellulosic and ceramic fibers – ceramic papers – for high temperature applications. Although a decrease in their mechanical properties due to calcination was observed, zeolitic ceramic papers resulted easy to handle for practical applications. Zeolite was quantified through BET surface area measurements. SEM images indicated a good dispersion of zeolite particles within the cellulosic paper whereas in the ceramic paper they appeared anchored on ceramic fibers. The zeolitic papers prepared resulted efficient as toluene sorbents, the adsorption capacities of zeolitic ceramic papers being higher than those of zeolitic cellulosic papers. In the case of zeolitic cellulosic papers, the amounts of released toluene were lower than those of adsorbed toluene, implying that the treatment up to 160°C did not completely eliminate the hydrocarbon. Also, TPD profiles showed that toluene is chemically retained up to high temperatures (ca. 420°C) in zeolitic ceramic papers. Toluene adsorption values demonstrate that zeolite dispersed into the cellulose/ceramic matrix is as effective as powder massive zeolite in retaining the hydrocarbon, which highlights the potential application of these zeolitic structures as sorbent materials both for low and high temperatures. [Copyright &y& Elsevier]

In this study, the influences of ultrasonic pretreatment factors (frequency, power, treatment time) on blends of municipal solid waste (MSW) and paper sludge (PS) with additive (MgO) was explored, through orthogonal experiments design. The optimum operating condition wanted to be acquired. However, for the ultimate (H/C) and ash analysis after pretreatment, solid residue mass and oxygenates compounds contents in products, the influences of factors were in different results. With adding PS unceasingly, the contents of hydrocarbon compounds decreased. And the ultrasonic pretreatment had the obvious influence with high PS percentage. Longer treatment time resulted to the lower content of oxygenates compounds. After adding MgO, the residue mass reduced, which meant MgO had the catalytic action, and the oxygenates compounds content reduced only with 100 kHz, which had the sonochemical effect. [ABSTRACT FROM AUTHOR]

Obligate social parasite insects are specialized in exploiting the parental service of the workers of another social species by invading their colonies. As social insects are usually aggressive towards intruders, social parasites have to circumvent the host’s nestmate recognition system to enter the host colony successfully. Many studies on paper wasps have shown that, after host nest invasion, Polistes social parasites change their chemical profile to match the host’s odour, thus allowing their acceptance into its colony. However, a social parasite’s usurpation strategy may benefit from signals that reduce or eliminate the aggression of the host. We used lure presentation experiments to investigate whether Polistes sulcifer, a social parasite of the paper wasp P. dominulus, is able to reduce the aggressive reaction of its host. We found that the parasite lure elicited lower host aggressiveness than the conspecific lure, suggesting that parasite species have evolved cues able to inhibit host aggressiveness. We investigated separately the effects of chemical and visual patterns on host aggressiveness. The lower host reaction to the parasite lure was not due to chemical cues, but was elicited by the visual facial pattern of the parasite. Experimental manipulation of this visual pattern demonstrated that the black lower part of the clypeus of the parasite is the trait able to reduce host aggression. This pattern can be considered an honest signal since it visually amplifies the mandibular width, giving information about the parasite’s dangerousness. [Copyright &y& Elsevier]

A previously uncultured Propionibacterium was isolated from a highly diluted sample (10−6 mL) of activated sludge of paper mill effluent. The isolate MOB600 was able to grow on anisole, phenetole, benzene, toluene, phenol, styrene and biphenyl, although it used only limited carbon sources in the minimal media. The partial DNA sequence of 16S ribosomal RNA gene was 93% identical to Luteococcus peritoni CCUG38120 as the closest neighborhood in the family Propionibacteriaceae. Strain MOB600 produced 2-methoxyphenol and 2-ethoxyphenol seemingly in an unproductive pathway from the degradation of anisole and phenetole, respectively. It had a substrate preference to favor 3-alkoxyphenols over 2-alkoxyphenols. Formation of 3-hydroxylated O-aryl alkyl ether was substantially proved by the nearly 1:1 biotransformation of substrate-analogous 1,2-methylenedioxybenzene to 3,4-methylenedioxyphenol (sesamol) showing end-product inhibition. The strain converted 2-/3-methoxyphenols to 3-methoxycatechol. The extradiol ring fission of 3-methoxycatechol appeared to take place in the production of a yellow-colored 2-hydroxymuconate derivative, thereby being able to release methanol spontaneously. High specificity polymerase chain reaction screening for bacterial dioxygenases revealed that the genomic DNA encoded at least three ring-hydroxylating dioxygenase large subunits. Being consistent with substrate availability for this strain, the obtained sequences were closely related to large subunits of an isopropylbenzene 2,3-dioxygenase, a benzene 1,2-dioxygenase, a biphenyl 2,3-dioxygenase, a benzoate 1,2-dioxygenase and a putative dioxygenase in Rhodococcus strains. Our results demonstrate that strain MOB600 may play a major role in the degradation of lignin-like O-aryl alkyl ethers and various aromatic hydrocarbon pollutants in activated sludge of paper mill effluent. [Copyright &y& Elsevier]

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]

Multi-wall carbon nanotubes (MWCNTs) have been synthesized on a carbon fiber paper (CFP) via a simple surface reaction of hydrocarbon decomposition using nickel nanoparticles as catalysts at 1023 K. Pd nanoparticles supported on MWCNTs/CFP are used as electrocatalysts for ethanol electrooxidation in alkaline media. The results shows that the Pd/MWCNTs/CFP electrocatalyst gives higher reaction activity and more stable performance than the commercial Pd/C and Pd/CFP electrocatalyst for ethanol oxidation in alkaline medium. [ABSTRACT FROM AUTHOR]

The Cauvery Basin is one of the prolific hydrocarbon-producing basins of southern India. The pericratonic basin has five sub-basins separated by five basement and structural highs formed by granitic and gneissic rocks of the Archaean Southern Granulite Terrane. The sub-basins have excellent Cretaceous source rocks and hydrocarbon-bearing reservoirs of different geological ages. Commercial hydrocarbons are produced from the Archean basement highs, specifically from the Kumbakonam–Madanam palaeo-highs of the Cauvery basin. The paper addresses basement characterisation using conventional as well as advanced well logs for accurate characterisation of the basement reservoirs. Basement reservoirs are challenging in terms of sporadic porosity and permeability distribution. Most of the porosities and permeability are attributed to secondary generation by fracturing and weathering. The present work aims to understand and compare the petrophysical attributes of two kinds of basement reservoirs (fractured basement and weathered basement) on the Kumbakonam–Madanam High. Two wells from each type lying on either side of the Madanam High were selected. Well log data, including gamma-ray, resistivity, porosity (neutron and bulk density), acoustic logs and advanced logs, such as resistivity images and dipole acoustic and elemental capture spectroscopy logs, from these four wells were analysed for their petrophysical understanding. Furthermore, image and acoustic log data were integrated to characterise the fracture geometry and fracture permeability of the basement reservoirs. Conventional log suites showing low GR, low resistivity, high density, and high neutron porosity are indicative of intricate lithologies, possibly mafic rocks. A notable negative crossover in density and neutron log along with excess Si concentration indicates weathering. A higher fracture density with a crisscross fracture/mesh fracture pattern is indicated by the analysis of image logs, shear wave anisotropy, and Stoneley fractures. Thus, a comparison of the petrophysical attributes of both fields is attempted to understand the fractured and weathered basement reservoirs and their geological characteristics. In conclusion, the basement reservoirs of the Madanam High Field are of interest because of their hydrocarbon-producing ability, and proper synthesis of petrophysical attributes will help develop activities in the basement reservoirs. [ABSTRACT FROM AUTHOR]

Soil contamination due to urban and industrial activities has caused significant land degradation and changes in the geotechnical properties of soils. Among many contaminants, hydrocarbons pose severe threats not only from an engineering point of view but are also hazardous to the environment. This review article critically analyzes the essential aspects of different hydrocarbon types as a contamination source in various soil types and their implications in the geotechnical design. The modifications of geotechnical properties require an in-depth investigation, especially at the micro-scale, by assessing the soil particle interaction with hydrocarbons. The hydrocarbon compounds possess the ability to alter the morphological characteristics of soil particles, which, in turn, influences the shear mobilization in soils. Furthermore, several remediation techniques, such as biological, chemical, physical, or thermal treatment methods, are available to solidify, remove or immobilize hydrocarbons. However, limitations exist due to the applicability of some techniques. Taking these considerations into account, the primary purpose of this paper is to create a consensus about how hydrocarbons interact with different soils, what are the triggers of these interactions, which geotechnical properties are mostly affected, which remediation techniques will be more effective, and how quickly the method can be applied. [ABSTRACT FROM AUTHOR]

The uplift–depression framework controls the source–reservoir assemblage. However, the exploration breakthrough is restricted by an insufficient understanding of the uplift–depression differentiation framework in the Early Cambrian Keping–Wensu area. In this paper, based on field outcrops evaluations, thin section analysis, logging data, drilling data, and 3D seismic data, Wensu low paleo-uplift was discovered in the northern Tarim Basin, and the planar distribution was demonstrated in detail, generally shown as a SW–NE trending nose structure, extending roughly 114 km in length to the southwest, about 35 km in width to the northeast, and with the overall characteristic of being high in the west and low in the east. During the Early Cambrian, the Tabei paleo-uplift evolved into the Wensu low paleo-uplift and largely died out by the Middle Cambrian, with the development of ramps and rimmed carbonate platforms. The tectonic-sedimentary evolution of the uplift–depression framework controlled the development of a set of main source rocks and two sets of large-scale effective reservoir rocks in the Lower Cambrian, constituting two sets of effective hydrocarbon accumulation in the upper and lower stratigraphic parts of the basin. Among them, the upper assemblage holds more potential for hydrocarbon exploration, and is expected to be a next strategic target area for hydrocarbon exploration of Cambrian subsalt in the Keping–Wensu area. [ABSTRACT FROM AUTHOR]

Based on recent developments, hydrogen-based combustion systems have received wide attention, mainly due to increasing awareness of enduring environmental pollutants and restricted access to fossil fuel usage. In the relevant literature, there are evidences of the possibilities on the partial or total replacement of hydrocarbon fuels with hydrogen in power plants and vehicle engines. However, some challenging issues particularly on hydrogen storage are remained to be resolved. This paper reviews and comments on addressing the effectiveness of hydrogen-enrichment on the engines and burners׳ performance includes the chemical kinetic analysis, the flame propagation structures and the effects of inhibitors on global burning velocity of hydrogen–hydrocarbon mixtures in different combustion bombs, chambers and vessels. It is recommended that future researches should aim towards the different application of hydrogen–hydrocarbon i.e. transportation and clean energy carrier. [ABSTRACT FROM AUTHOR]

Gold tube thermal simulation experiments represent a pivotal tool in exploring hydrocarbon generation kinetics in hydrocarbon source rocks. Compared to other reaction systems, the reaction environment and the pyrolysis product composition within the gold tube display a greater resemblance to actual geological conditions, especially for coal-based hydrocarbon rocks with poor hydrocarbon removal capacity. The kerogen is in close contact with various pyrolysis products and reacts with each other in the gold tube. Researchers have carried out extensive research and application in hydrocarbon generation kinetics based on gold tubes in recent years. But a systematic and comprehensive summary of these studies is lacking. This paper provides a review of the kinetic study based on golden tubes in recent years from the perspectives of research objects, influencing factors, applications and problems. The main targets of hydrocarbon generation kinetics based on gold tubes include CH4, C1-5, C8+ and so on. Elucidating the kinetics of diverse pyrolysis products aids comprehension of the mechanism of organic matter pyrolysis. Reaction condition, minerals and organic structure all influence hydrocarbon production kinetics. Clarifying the effects of these influencing factors is of great importance in understanding the pyrolysis mechanism of hydrocarbon source rocks and pyrolysis research in the domain of hydrocarbons. Golden tube-based kinetic studies of hydrocarbon production have good potential application, not only in determining the hydrocarbon generation history of hydrocarbons in the study area, but also in studying the genesis, origin, and reservoir formation mode of natural gas. This paper also summarizes some problems and solutions of the gold tube hydrocarbon generation kinetics, such as the inhomogeneity of the samples, the difference between the gold tube system and natural conditions, and the determination of the time point of oil secondary cracking. Continuous optimization of the solution enhances the authenticity of the golden tube simulation experiment. This review aims to offer a theoretical foundation and research suggestions for investigating pyrolysis kinetics of hydrocarbon source rocks and hydrocarbons based on golden tubes. [ABSTRACT FROM AUTHOR]

A new approach is presented in this paper for the dynamic modeling of the chemical and isotopic evolution of C1–3 during the hydrocarbon generation process. Based on systematic data obtained from published papers for the pyrolysis of various hydrocarbon sources (type I kerogen/source rock, type II kerogen/source rock, type III kerogen/source rock, crude oil, and asphalt, etc.), the empirical evolution framework of the chemical and isotopic composition of C1–3 during the hydrocarbon generation process was built. Although the empirical framework was built only by fitting a large amount of pyrolysis data, the chemical and isotopic composition of C1–3 derived from the pyrolysis experiments all follow evolution laws, convincing us that it is applicable to the thermal evolution process of various hydrocarbon sources. Based on the simplified formula of the isotopic composition of mixed natural gas at different maturities (δ13Cmixed), δ13Cmixed = X × n i A × δ 13 C i A + Y × n i B × δ 13 C i B X × n i A + Y × n i B , it can be derived that the cumulative isotopic composition of alkane generated in a certain maturity interval can be expressed by the integral of the product of the instantaneous isotopic composition and instantaneous yield at a certain maturity point, and then divided by the cumulative yield of alkane generated in the corresponding maturity interval. Thus, the cumulative isotopic composition (A(X)), cumulative yield (B(X)), instantaneous isotope (C(X)), and instantaneous yield (D(x)) in the dynamic model, comply with the following formula during the maturity interval of (X0~X). A(X) = ∫ X 0 X C X × D X d x B (X) , where A(X) and B(X) can be obtained by the fitting of pyrolysis data, and D(x) can also be obtained from the derivation of B(X). The dynamic model was applied on the pyrolysis data of Pingliang Shale to illustrate the quantitative evolution of the cumulative yield, instantaneous yield, cumulative isotope, and instantaneous isotope of C1–3 with increasing maturity. The dynamic model can quantify the yield of methane, ethane, and propane, as well as δ13C1, δ13C2, and δ13C3, respectively, during the hydrocarbon generation process. This model is of great significance for evaluating the natural gas resources of hydrocarbon source rock of different maturities and for identifying the origin and evolutionary process of hydrocarbons by chemical and isotopic data. Moreover, this model provides an approach to study the dynamic evolution of the isotope series of C1–3 (including reversed isotopic series), which is promising for revealing the mechanism responsible for isotopic reversal when combined with post-generation studies. [ABSTRACT FROM AUTHOR]

Insect social life is governed by chemicals. A great number of studies have demonstrated that the blend of hydrocarbons present on the cuticle (CHCs) plays a pivotal role in intra- and inter-specific communication. It is not surprising, therefore, that social parasites, specialized in exploiting the costly parental care provided by host workers, exploit the host chemical communication system too. Throughout their life cycle, social parasites intercept and break this CHC-based code. Recently, however, several polar compounds (mainly peptides) have been found in addition to CHCs both on the cuticle and on the comb surface of social insects, and their semiochemical role has been demonstrated in some circumstances. In the present study, we used the paper wasp social parasite-host system Polistes sulcifer (Zimmerman)-Polistes dominulus (Christ) to evaluate the relative importance of the CHC5 and polar compounds in two different steps of the host exploitation process: host nest detection by the pre-usurping parasite and parasite chemical integration into the host colony. After separating the polar and apolar fractions of the host nest as well as those of pre- and post-usurpation parasites, we carried out laboratory assays based on the binary choice model. Our results show that nest polar compounds neither are used by the parasite to detect the host's nest nor play a role in parasite chemical integration into the host colony. In contrast, we demonstrate that CHCs are fundamental in both steps, thus confirming their primary role in social insect life and consequently in social parasite-host interactions. [ABSTRACT FROM AUTHOR]

Abstract: Architectonics of the paper-structured catalyst for the application to the biofuel reformer or direct internal reforming SOFC (DIRSOFC) was studied. Inorganic fiber network, “paper”, composed of yttria-stabilized zirconia (YSZ) fiber (Zf), alumina fiber (Af) and inorganic binder (Al2O3 sol (As) or ZrO2 sol (Zs) or CeO2 sol (Cs)) was prepared by a simple paper-making process. Then, the catalytic activities of the Ni and Ni–MgO loaded papers called “paper-structured catalysts (PSCs)” for the steam reforming of biodiesel fuels (BDFs) were evaluated. Ni–MgO loaded PSC using Cs as an inorganic binder, Ni–MgO/ZfAfCs, exhibited excellent performance over Ru/γAl2O3 catalyst beads. Formation of light hydrocarbons, especially C2H4, was eliminated and water–gas shift reaction was more promoted compared to the catalyst beads. [Copyright &y& Elsevier]

Evaluates the role of hydrocarbon classes to define the recognition signature within the cuticular chemical profile of paper wasps. Effect of linear alkanes and alkenes on recognition response; Influence of the augmentation of a single alkene or methyl-branched alkane found on the cuticle on the recognition of the signature; Effect of genetic and environmental differences on epicuticular lipids.

In this study, a mixture of waste plastics and papers were pyrolyzed under mild conditions in batch and tubular reactors. The decomposition reactions were enhanced by the use of synthetic zeolite-based catalysts to obtain a higher yield of volatiles and modifying the product composition. Especially the decomposition reactions and the product properties obtained from the different reactors were compared. Gases were analysed by GC-FID and GC-TCD. This fraction contains hydrogen, carbon-monoxide, carbon-dioxide and hydrocarbons. The pyrolysis oils have oxygen-containing compounds, such as alcohols, aldehyde, ketones, carboxylic acids or phenol and its derivative. Not only the reactor configurations but also the catalysts had an effect to the product properties, because the catalysts with alkali characters showed advanced behaviour in the reduction of oxygenated hydrocarbons, while high synthetic zeolite catalysts can increase the saturation and isomerization reactions. The long-term behaviour of the pyrolysis oils was followed by an accelerated aging test at 80 °C till 7 days. The catalysts can effectively reduce the rate of density and viscosity increase during the aging and the alkali catalysts showed beneficial properties in reducing the acidic components. In general, the aging properties were more favorable for pyrolysis oils obtained from the tubular reactor compared with the results in batch reactor. • Co-pyrolysis of plastic and paper wastes were investigated. • Better product properties could be obtained from tubular reactor. • Batch process can supported the in-situ saturation of olefins. • High alkali content catalysts can improve the corrosion properties of light oils. • Light oils had high TAN and can occur very low weigh loss. [ABSTRACT FROM AUTHOR]

Thermal papers, commonly used for printed receipts or lottery tickets, are omnipresent in our everyday life. They are regarded as semi-porous substrates, and yet can be critical to analyze when looking for latent fingermarks due to their thermosensibility. The aim of this study was to investigate a development sequence that would better combine the adequate detection techniques in order to maximize the chances to develop latent fingermarks left on these substrates. Different methods of development have been compared on test substrates: black magnetic powder, Lumicyano™, thermal development, ninhydrin and 1,2-indanedione/ZnCl2. Whitening stages and thermal development have been focused on, tested and optimized. The results of these preliminary tests enabled the study of three development sequences. They have subsequently been compared to the one currently used in the Gendarmerie's laboratories and the best results have been provided during pseudo-operational comparative trials by one of these sequences, consisting in 6 stages. [ABSTRACT FROM AUTHOR]

Abstract: In this study, performance of solid oxide fuel cell (SOFC) connected with paper-structured catalyst (PSC) was evaluated in the direct feed of wet oleic fatty acid methyl ester (oleic-FAME, C19H36O2), which is a mono-unsaturated component of practical biodiesel fuels (BDFs), in the steam to carbon ratio (S/C) range between 2.0 and 3.5, and high current density of 1 A cm−2 (at 0.7 V) was recorded at 800 °C. Long term stability of oleic-FAME fueled SOFC was achieved by the incorporation of PSC into SOFC even under severe operating condition prone to coking (direct feed of unsaturated hydrocarbon with carbon number 19 and low S/C ratio of 2.0). After 100 h test, coking was not observed in both SOFC anode and PSC. [Copyright &y& Elsevier]

Substantial amounts of organo-pollutants, often persistent and toxic, are generated globally each year, posing a threat to soil, water, groundwater, and air. The pollutants encompass a wide range of substances from various sources, which include solid as well as liquid ones, such as landfill leachates and wastewaters. The compounds include paper and pulp mill byproducts, pharmaceuticals, diverse types of plastics, hydrocarbons, pigments, and dyes, as well as pesticides and insecticides. Fungal bioremediation stands out as a promising technology that uses the metabolic potential of fungi to eliminate or mitigate the impact of pollutants. Notably, species of the genus Pycnoporus exhibit significant capabilities for degrading a broad spectrum of toxic molecules. This degradation is facilitated by released ligninolytic enzymes, especially laccase, and cellular enzymes pertaining to the cytochrome P450 monooxygenase system. The laccase, which is overproduced by the genus Pycnoporus, is quite remarkable for its high redox potential. The objective of this review is to highlight the proficiency of the Pycnoporus genus in the degradation of pollutants in submerged and solid-state fermentation. Recent studies conducted over the past decade consistently highlight the Pycnoporus genus as a robust contender in the realm of white biotechnology. [ABSTRACT FROM AUTHOR]

Ethanol as a renewable fuel has been applied in fuel vehicles (FVs), and it is promising in hybrid electric vehicles (HEVs). This work aims to investigate the emission characteristics of ethanol applied in both FVs and plug-in hybrid electric vehicles (PHEVs). The paper conducted a real-road test of an internal combustion FV and PHEV, respectively, based on the world light vehicle test cycle (WLTC) by using gasoline and regular gasoline under different temperature conditions. The use of E10 and E20 in FVs has been effective in reducing the conventional emissions of the vehicles. At 23 °C, E10 and E20 reduced the conventional emissions including carbon monoxide (CO), total hydrocarbon compound (THC), non-methane hydrocarbon compound (NMHC), particulate matter (PM), and particulate number (PN) by 15.40–31.11% and 11.00–44.13% respectively. At 6 °C, E10 and E20 reduced conventional emissions including THC, CO, and PM by 2.15–8.61% and 11.02–13.34%, respectively. However, nitrogen oxide (NOX) emissions increased to varying degrees. The reduction trend of non-conventional emissions including methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) from FVs fueled with E10 and E20 is not significant for vehicles. Overall, the emission reduction effect of E20 is better than that of E10, and the emission reduction effect of ethanol gasoline on vehicle emissions is reduced at low temperatures. Lower ambient temperatures increase vehicle emissions in the low-speed segment but decrease vehicle emissions in the ultra-high-speed segment. HEV emissions of THC, CO, PN, and PM are reduced by 25.28%, 12.72%, 77.34%, and 64.59%, respectively, for E20 compared to gasoline, and the use of E20 in HEVs contributes to the reduction of overall vehicle emissions. [ABSTRACT FROM AUTHOR]

It is well known that the existing horizontal-well-drilling and hydraulic fracturing technology used to achieve large-scale, cost-effective production from immature to low–moderate-maturity continental shale in China, where the organic matter mainly exists in solid form, is fairly ineffective. To overcome the obstacles, in situ conversion technology seems feasible, while implementing it in the target layer along with estimating the amount of expected recoverable hydrocarbon in such shale formations seems difficult. This is because there are no guidelines for choosing the most appropriate method and selecting relevant key parameters for this purpose. Hence, based on thermal simulation experiments during the in situ conversion of crude oil from the Triassic Chang 73 Formation in the Ordos Basin and the Cretaceous Nenjiang Formation in the Songliao Basin, this deficiency in knowledge was addressed. First, relationships between the in situ-converted total organic carbon (TOC) content and the vitrinite reflectance (Ro) of the shales and between the residual oil volume and the hydrocarbon yield were established. Second, the yields of residual oil and in situ-converted hydrocarbon were measured, revealing their sensitivity to fluid pressure and crude oil density. In addition, a model was proposed to estimate the amount of in situ-converted hydrocarbon based on TOC, hydrocarbon generation potential, Ro, residual oil volume, fluid pressure, and crude oil density. Finally, a method was established to determine key parameters of the final hydrocarbon yield from immature to low–moderate-maturity organic material during in situ conversion in shales. Following the procedure outlined in this paper, the estimated recoverable in situ-converted oil in the shales of the Nenjiang Formation in the Songliao Basin was estimated to be approximately 292 × 108 tons, along with 18.5 × 1012 cubic meters of natural gas, in an area of approximately 8 × 104 square kilometers. Collectively, the method developed in this study is independent of the organic matter type and other geological and/or petrophysical properties of the formation and can be applied to other areas globally where there are no available in situ conversion thermal simulation experimental data. [ABSTRACT FROM AUTHOR]

Low-to-medium maturity lacustrine shale oil resources have enormous potential and are projected to play a crucial role in the massive scale-up of crude oil production in China in the near future. The in-situ conversion process is currently the only effective means of utilizing this resource. Nevertheless, significant scientific challenges and technological bottlenecks still exist. Under this circumstance, the National Natural Science Foundation of China approved an integrated project of the Enterprise Innovation and Development Joint Fund titled "The Mechanism of Low-to-medium Maturity Lacustrine Shale Oil Resource Formation and its in-situ Conversion and Exploitation". This project aims to systematically investigate the entire process of in-situ conversion for low-to-medium maturity shale oil resources and lay a solid scientific and technological foundation for advancing the smooth implementation of on-site pilot trials. This paper presents the latest progress in this field and summarizes the existing scientific and technological challenges that need to be addressed. With the foundational support of the above project, our research team has made significant progress in several fields, including the formation mechanisms of organic matter superrich shale, low-to-medium maturity shale oil enrichment area evaluation, heat and mass transfer dynamics, coupled fluid field and hydrocarbon expulsion efficiency, exploitation methods, among others. Despite these theoretical advances, several major challenges were identified, which help to further focus on the critical scientific issues, determine the in-situ conversion technique-developing direction, and formulate a feasible implementation plan for future resource utilization. [ABSTRACT FROM AUTHOR]

Carbon nanotubes filled with organic molecules can serve as chemical nanoreactors. Recent experimental results show that, by introducing cyclic hydrocarbon molecules inside carbon nanotubes, they can be transformed into nanoribbons or inner tubes, depending on the experimental conditions. In this paper, we present our results obtained as a continuation of our previous molecular dynamics simulation work. In our previous work, the initial geometry consisted of independent carbon atoms. Now, as an initial condition, we have placed different molecules inside a carbon nanotube (18,0): C5H5 (fragment of ferrocene), C5, C5+H2; C6H6 (benzene), C6, C6+H2; C20H12 (perylene); and C24H12 (coronene). The simulations were performed using the REBO-II potential of the LAMMPS software package, supplemented with a Lennard-Jones potential between the nanotube wall atoms and the inner atoms. The simulation proved difficult due to the slow dynamics of the H abstraction. However, with a slight modification of the parameterization, it was possible to model the formation of carbon nanoribbons inside the carbon nanotube. [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]

Methods were developed to coat Whatman No. 1 filter paper for the extraction of polycyclic aromatic hydrocarbons (PAHs) from water. The filter paper samples were coated using solutions of poly(hydrogenmethylsiloxane) and dichlorodimethylsilane. The coated paper samples were tested for extraction of polar aromatic compounds and polycyclic aromatic compounds from aqueous solutions. The extracted compounds were detected using solid-matrix fluorescence (SMF) and solid-matrix phosphorescence (SMP). Also, the limits of detection and effective partition coefficients for the compounds were calculated for the coated papers. The limits of detection and effective partition coefficients were compared to those obtained using 1PS paper as an extraction medium. Both coated filter paper samples were shown to be more effective than Whatman 1PS for extraction of polycyclic aromatic hydrocarbons. However, the paper treated with poly(hydrogenmethylsiloxane) gave the best extraction properties and a limit of detection of 29 fmol/ml for benzo[e]pyrene. The paper coatings were characterized using near- and mid-infrared reflectance spectroscopy. In addition, 1PS paper was determined to contain 1.04 wt.% poly(dimethylsiloxane) (PDMS). [Copyright &y& Elsevier]

Abstract: The aliphatic and polycyclic aromatic fractions of dust collected in the vicinity of recycled paper processing operations were analyzed using gas chromatography/mass spectrometry. Total measured dust concentration (up to 8.73±2.02mg/m3) fluctuated substantially in the different steps of paper manufacture. This was attributed to the type of the operation such as, the release of fibers and particles during paper cutting and the use of reactive chemicals and excessive water under high temperature and pressure during the bleaching and the water rinsing/drying step. Particulate polycyclic aromatic hydrocarbons (PAHs) (from fluorene to benzo[ghi]perylene with mean concentrations from 3.8±0.5 to 41.4±0.4ng/m3) and the unresolved mixture of branched, cyclic and unsaturated hydrocarbons (UCM) were measured in all samples while, n-alkanes from n-C20 to n-C27, were only observed in cutting and packaging areas (from 180.6±18.9 to 4297.9±794.9ng/m3). The profile of occupational PAHs in bleaching and treatment of contaminated recycled raw paper was comparable to that observed for anthropogenic activities. The values of molecular diagnostic ratios indicated the contribution of oil residues and emissions from worklifts and other equipment used for pulp and paper handling. Total benzo[a]pyrene-equivalent (BaP) concentrations of particulate PAHs (varied from 323 up to 1104pg/m3), provided evidence that workers were exposed to high quantities of PAHs as compared with exposures to urban air and other indoor settings, posing long-term threat to their health. [Copyright &y& Elsevier]

Abstract: Several studies have shown that differences in the relative abundance of cuticular hydrocarbons occur between reproductives and non-reproductives in many social insects. These differences also exist between Polistes dominulus foundresses and their first emerged daughters (usually indicated as workers), but they gradually disappear when workers from orphaned colonies develop their ovaries and assume a reproductive role in the colony. However, hydrocarbons are not the exclusive components of cuticular layer of wasps. Mass-spectrometry analysis of cuticular methanol extracts from Polistes paper wasps showed a complex pattern of polar substances, partly or totally proteinaceous in nature. We found that these compounds, ranging from 918 to 2679Da, showed a clear caste differentiation between foundresses and their first emerged daughters (usually indicated as “workers”), both in queen-right and in orphaned colonies. Conversely to hydrocarbons, workers from orphaned colonies maintain a significant difference from foundresses in the pattern of the medium molecular weight (MW) polar compounds obtained by MALDI-TOF. On the basis of such results we hypothesize that a reliable cue to identify foundresses from daughters, and not only their reproductive status, may exist in Polistes wasps. Although the great majority of previous work on social insect communication has focused on cuticular hydrocarbons, our findings suggest that the medium MW component of cuticular substances may be involved in recognition. [Copyright &y& Elsevier]

Differences in long-chain hydrocarbon mixtures among reproductive and nonreproductive individuals have been often revealed in social insects. However, very few papers demonstrated that these signatures actually act as contact pheromones used by nonreproductive to recognize the presence of a related queen in the colony. Cuticular and glandular hydrocarbons of Polistes paper wasps have been extensively studied, but, until now, the perception and recognition of such cues was not demonstrated. In this paper, we show, for the first time in Vespidae, that Polistes gallicus workers distinguish nestmates from alien individuals and queens from workers by the hydrocarbon mixtures of the Van der Vecht organ secretion (VVS). We also demonstrated that stroking behavior (a peculiar behavior of Polistes by which queens probably lay VVS on the nest) acts as an inhibitor of ovarian development in workers. [ABSTRACT FROM AUTHOR]

The responses of shortfin eel (Anguilla australis) to discharges from two pulp and paper mills, municipal wastewater, and a geothermal power plant wastewater were examined. Eels were caged at 3 sites along the Tarawera River, North Island, New Zealand, to explore effects of a 3-wk exposure down a contamination gradient (Ref → D1 → D2). Most of the observed effects were seen in eels caged at the furthest downstream site (D2), below all the discharge areas. General hematology in eels was unaffected, as measures did not differ markedly at the two downstream sites compared with the reference site. At D2, eels were significantly lighter per unit length (reduced condition factor), although liver and spleen size (LSI and SSI) were unaffected. Significantly elevated circulating sex steroid concentrations (testosterone and estradiol) were measured in D2 eels and increasing sex steroid levels at both sites downstream of the reference site were observed. Significant ethoxyresorufin O-deethylase (EROD) activity induction was seen in D2 eels and bile chemistry showed significant accumulation of pyrene and retene equivalents. However, significantly greater concentrations of total resin acids were found in the bile of eels from the intermediate site (D1), between the two pulp and paper mills. The higher polycyclic aromatic hydrocarbon (PAH) equivalents found in the bile of D2 eels suggest that resin acid neutrals, particularly retene, are responsible for some of the effects observed in eels at the furthest downstream exposure site. Levels of pulp and paper mill extractives in sediment, including the PAH retene, support this conclusion. [ABSTRACT FROM AUTHOR]

Abstract: A new tar destruction technology has been developed by integrating in-situ catalytic gasification and a hot-gas cleaning system in the catalytic gasification of paper-reject sludge. Experimental results indicated that the tar yield in syngas decreased significantly from 13.64 to 10.76 g/m3, when increasing the zeolite addition during in-situ catalytic gasification. When the syngas passed through the hot-gas cleaning system, the tar concentration measured from downstream was approximately 0.22 g/m3. The hot-gas cleaning system used in this research seems to have played a significant role in reducing tar concentration of the syngas. The major tar speciation identified after hot-gas cleaning system was 1-ring or 2-ring hydrocarbons, which included benzene, toluene, xylene, styrene and naphthalene. In summary, the energy yield efficiency of syngas will be enhanced due to the tar reduction and transformation. The syngas seems to be appropriate to use as a fuel in gas engines for electricity generation. [Copyright &y& Elsevier]

The influence of the physical and chemical characteristics of a paper substrate coated with a thin homogeneous film of poly(vinyl alcohol) (PVA) has been investigated. Some of the paper specimens were temperature-gradient (TG) calendered (at high temperatures) before pilot-scale coating. Two different paper grades differing in structure and sizing formulation were used. For one of the grades, the high-temperature calendering had a slight effect on the chemical composition of the paper surface as evaluated by electron spectroscopy for chemical analysis. For the other grade, no such effect was noted. In the former case, it was suspected that the sizing in the paper substrate degraded and, as a consequence, that volatile hydrocarbons evaporated from the surface. The slight change in surface chemistry had no significant direct effect on the homogeneity of the applied polymer film. The results indicated that the surface roughness of the substrate was the governing factor. The low surface roughness obtained by TG-calendering was beneficial for the homogeneity and barrier properties. In one series of experiments, some of the paper substrates (uncalendered and calendered) were corona-treated before PVA-coating. This treatment greatly increased the wettability of the surface by water. In general, the corona treatment improved the homogeneity and the barrier properties (grease resistance, air permeability and water vapour transmission) of the applied film. The surface smoothness was clearly important also for the corona-treated papers. [Copyright &y& Elsevier]

Comments on the paper "Age Dating of Environmental Organic Residues," by Isaac Kaplan. Elucidation of the important issues on the use of lead isotopes and nC17/Pr (n-heptadecane/Pristane) ratios to estimate the age of hydrocarbon releases into the environment; Summarization of Anthropogenic Lead ArchaeoStratigraphy (ALAS) model; Validity of the lead isotope ratios as ALAS model calibration points; Relationship between U.S. aerosol lead isotopes ratios and those of the ALAS model; Clarification on the manufacture and distribution of alky-lead.

Today, conversion of hydrocarbons is one of the most common hydrogen production technologies. This paper presents a design of a high-temperature reactor — the main component of a hydrogen production unit using partial oxidation of hydrocarbons — as well as a physical model of gas generation. It also presents a schematic diagram of an experimental setup as well as results of experimental studies on steady-state modes of partial oxidation in the combustion chamber of a high-temperature reactor for various hydrocarbon feed/oxidant combinations. In the course of the study, we identified patterns that describe how the excess oxidant ratio affects the composition of products of incomplete combustion of hydrocarbons to obtain hydrogen-containing gas of the required composition and parameters for hydrogen production. We propose a method to calculate nominal geometric dimensions of a high-temperature reactor, which makes it possible to estimate its weight and size at the design stage. The paper presents results of experimental studies confirming the adequacy of the proposed method. • Production of hydrogen by the method of partial oxidation of hydrocarbons. • Design of a high-temperature reactor and a physical model of the gas generation process. • The design of the main units and the method for calculating the nominal geometric dimensions of a high-temperature reactor. • Scheme of the experimental setup and results of experimental studies. • Patterns of the influence of the oxidizer excess coefficient on the composition of products of incomplete combustion of hydrocarbons. [ABSTRACT FROM AUTHOR]

Selective oxidation of tetralin by molecular oxygen over mesoporous CrMCM-41 molecular sieve catalyst using supercritical carbon dioxide (scCO2) solvent has been investigated. CrMCM-41 catalyst gave high selectivity (96.2%) and good yield (63.4%) of 1-tetralone. The presence of scCO2medium improves 1-tetralone selectivity and suppresses leaching of chromium from the CrMCM-41. The activity over recycled CrMCM-41 remains nearly the same under the present experimental conditions. The effect of the reaction parameters on CrMCM-41 was also studied in detail along with comparison of its catalytic activities with other mesoporous catalysts, viz.MnMCM-41, CoMCM-41, microporous CrAPO-5, CoMFI, and macroporous Cr/SiO2catalyst, respectively. In addition this catalytic system was also applied for the oxidation of other benzylic compounds such as indane, fluorene, acenaphthene and diphenylmethane. [ABSTRACT FROM AUTHOR]

The synthesis of covalently linked dimers, containing two resorcin[4]arene moieties connected over two 9,10-functionalized anthracene units, is reported. Besides the synthetic route, which involves for example the formation of anthracene-9,10-dialkanols (4and 5), and characterization of the compounds, the photochemical properties, introduced through the anthracene groups, were investigated by means of UV/VIS spectroscopy. Both resorcin[4]arene dimers (1and 2) were able to undergo an intramolecular [4 + 4] cycloaddition, therefore changing the size of the inner cavity. Unfortunately, the back reaction, which was expected to take place on irradiation below 300 nm or upon heating, was not observed yet and will be the focus of our future work. [ABSTRACT FROM AUTHOR]

Philopatric behavior has been demonstrated in a wide taxonomic spread of animals. In temperate environments, overwinteredPolisteswasp foundresses often return to their natal nest prior to initiating colony construction. Previous research has shown that these spring foundresses can identify the natal nest in the absence of landmark and gross morphological cues. Hydrocarbons are essential recognition cues forPolistesnest and nestmate discrimination, but cuticular hydrocarbon profiles can become homogenized when foundresses overwinter in mixed colony groups. We examined the hydrocarbon profiles ofPolistes dominulusfoundresses and nests before and after an overwintering period, and found that the hydrocarbon profiles of nests remain unique over time and that this uniqueness is influenced by the original foundresses. Our data raise the possibility that in returning to the natal nest, foundresses reacquire their colony-specific signature, which may play a role in the formation of cooperative associations. [ABSTRACT FROM AUTHOR]

Schisandra chinensis (S. chinensis) has a long history as a traditional Chinese medicine that is astringent, beneficial to vital energy, tonifies the kidney, tranquilizes the heart, etc. Significantly, Schisandrol A (SA) is extracted from S. chinensis and shows surprising and satisfactory biological activity, including anti-inflammatory, hepatoprotective, cardiovascular protection, and antitumor properties, among others. SA has a more pronounced protective effect on central damaged nerves among its numerous pharmacological effects, improving neurodegenerative diseases such as Alzheimer's and Parkinson's through the protection of damaged nerve cells and the enhancement of anti-oxidant capacity. Pharmacokinetic studies have shown that SA has a pharmacokinetic profile with a rapid absorption, wide distribution, maximal concentration in the liver, and primarily renal excretion. However, hepatic and intestinal first-pass metabolism can affect SA's bioavailability. In addition, the content of SA, as an index component of S. chinensis Pharmacopoeia, should not be less than 0.40%, and the content of SA in S. chinensis compound formula was determined with the help of high-performance liquid chromatography (HPLC), which is a stable and reliable method, and it can lay a foundation for the subsequent quality control. Therefore, this paper systematically reviews the preparation, pharmacological effects, pharmacokinetic properties, and content determination of SA with the goal of updating and deepening the understanding of SA, as well as providing a theoretical basis for the study of SA at a later stage. [ABSTRACT FROM AUTHOR]

This paper presents the application of two versions of the multilayer fluidized bed made out of two materials with significantly different densities. The first type of fluidized bed was composed of raw cenospheres and quartz sand. The second type of fluidized bed was composed of cenospheres coated with iron oxides and quartz sand. A variable vertical density profiles in the prepared fluidized beds were confirmed, making them suitable for processing polymeric materials, specifically, polyolefins with a density below 1 g/cm3. The polyolefin pyrolysis process was investigated in both versions of the fluidized bed at temperatures of 520, 540, 560, and 590 °C. The products of the pyrolysis were monitored using high-resolution infrared spectroscopy (with a resolution of 1 cm−1). While the process is organized in these fluidized beds, the absence of the accumulation of solid residues is notable. The results show that the pyrolytic gaseous mixture is composed of numerous compounds, namely, unsaturated and saturated aliphatic hydrocarbons and benzene. The possibility of producing a gas rich in ethylene, propylene, and 1-butene during the pyrolysis was demonstrated. Additionally, during the pyrolysis of both polymers, the production of benzene was shown with yields, ranging from 5%wt. in the fluidized bed made out of raw cenospheres to 11 %wt. in the fluidized bed made out of cenospheres modified by iron oxides. Due to the complex nature of the resulting pyrolytic gas, it is suggested that we process the created gaseous mixtures entirely in a steam conversion process, making them a potential source of hydrogen. [ABSTRACT FROM AUTHOR]

The possibilities offered by the use of variational mode decomposition–based Hilbert marginal spectrum and the differential cepstrum for gas‐bearing detection are studied in this paper. We propose a novel variational mode decomposition–based Hilbert marginal differential cepstrum for hydrocarbon detection. Variational mode decomposition–based Hilbert marginal spectrum is first computed. Then discrete cosine transform is carried out to the differential logarithmic variational mode decomposition–based Hilbert marginal spectrum to obtain the variational mode decomposition–based Hilbert marginal differential cepstrum. For hydrocarbon detection, the seismic amplitude anomaly section is generated by extracting the first and second common quefrency sections. Compared with the traditional Fourier‐based cepstrum, the wavelet‐based cepstrum and the Berthil cepstrum, it has the ability to effectively reveal more detailed frequency‐dependent amplitude anomalies with high accuracy and resolution. Model tests and field data applications from a carbonate reservoir in China show that the variational mode decomposition‐based Hilbert marginal differential cepstrum can provide a better gas‐prone interpretation. The proposed method can be a complementary approach to current cepstrum‐based hydrocarbon detection methods and the spectrum decomposition methods. [ABSTRACT FROM AUTHOR]

In this paper, the hydrothermal synthesis of Na-A zeolite synthesized from Angren kaolin and γ-Al2O3 mixtures is considered. Crystal sizes of Linde Na-A and synthesized Na-A zeolite were compared using X-ray phase analysis. Zeolite Linde Na-A has a lattice strain between crystals from 0.019 to 0.23, and a lattice strain between synthesized Na-A zeolite crystals from 0.019 to 0.24. The dislocation density of the samples was found to be between 1014 m-2 and 1017 m-2. Using IR Spectrometric analysis was determined to be compatible with data presented in the literature. In this study, Angren kaolin was selected as the source of aluminosilicate available in Uzbekistan. Today, the use of zeolites for technological purposes is widely introduced worldwide, they are used in the production industry for purification of various gases, and in the oil and gas industry as an adsorbent and catalyst, for the separation of hydrocarbons, and for the deep purification of gases. [ABSTRACT FROM AUTHOR]

In multiple-foundress nests of the wasp Polistes dominulus, dominance hierarchies are established among foundresses, and only the dominant (=alpha) individual lays eggs. The alpha female can be distinguished from subordinate females and workers on the basis of the proportions of some hydrocarbons present on the cuticle, suggesting that chemical signaling of her reproductive status could occur. P. dominulus is also the host species of the obligate social parasite Polistes sulcifer. After aggressively usurping host colonies and behaviorally replacing the host alpha female, parasites are characterized by a change in the proportions of their cuticular hydrocarbons to match that of the host cuticular profile at both species and colony levels. In the current study, we demonstrate that P. sulcifer queens also modify their cuticular hydrocarbon proportions after usurpation to match that of the host alpha female. Parasite females, therefore, acquire the dominant rank in host colonies both reproductively and chemically by mimicking the typical alpha profile of the host. Parasite females were not able to fully inhibit ovary development in host foundresses, and 10 days after usurpation, parasites, alpha and beta foundresses show similar chemical profiles and ovarian development. [Copyright &y& Elsevier]