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The current research investigates the use of an automated cladding welding machine for wire arc additive manufacturing (WAAM) of a semi-cylindrical part using a 1.2 mm nickel- chromium-molybdenum alloy wire (ERNiCrMo-3). The gas tungsten arc welding process was adopted to create a 32 mm thick and 60 mm long part. Onwards, standard tests were performed to evaluate the part's hardness, yield, and tensile strengths at various sections along the part's length and thickness. One of the objectives was also to identify any potential change in the mechanical properties of the Nickel wire when employed in WAAM process. Moreover, microstructure along the depth was examined using SEM to ascertain bonding between deposited layers and identify any porosities. The material's hardness was found relatively higher than the original wire; somewhere about 27 HRC in the horizontal plane and 26.8 to 28.5 HRC in the vertical plane. Additionally, the study shows that the direction across the thickness (X) had the lowest values for both tensile and yield strength. While, examination at the microscopic level revealed that in both orientations: parallel (X) and perpendicular (Y) to the direction in which the layers were deposited, exhibited a high level of ductility. This confirms the possibility of an additive manufacturing procedure adopted for this super-alloy material without significantly changing its mechanical properties. While, there is room for improvement in properties by optimizing the machine parameters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Coconut shell emerged as a feasible feedstock. • Optimal ER ranges between 0.1 and 0.3, promoting higher syngas yields. • Plant D achieving a significantly lower levelized cost of electricity of US$0.19/kWh. • Larger plant (Plant C-D) demonstrates strong economic performance with a PBP of 3.28 years and 1.69. This research aims to evaluate the techno-economic viability and commercial potential of biomass gasification across different capacities. Sensitivity analysis was conducted based on an established downdraft gasifier model using Aspen Plus. Results underscored the significant impact of gasification temperature and equivalence ratio (ER) on syngas composition, low heating value (LHV), and cold gas efficiency (CGE). Among the feedstocks tested, coconut shell emerged as a feasible feedstock, yielding syngas with an LHV of 8.93 MJ/Nm3 and achieving a CGE of up to 71.12 %. Optimal gasification temperatures ranged between 750 °C to 1,000 °C, with peak ER falling within 0.1 to 0.3. Economic analysis revealed that smaller-scale operations like Plant A resulted in a negative net present value of − US$0.63 million, indicating unfavorable investments. The internal rate of return notably increased from 9.53 % for Plant B compared to −2.56 % for Plant A (20 kW). Plant D, with larger capacity of 20 MW, showed an impressive payback period of less than two years (1.69 years). Medium to large-scale plants such as Plant C (2 MW) and Plant D demonstrated greater economic resilience, with Plant D achieving a significantly lower levelized cost of electricity of US$ 0.19/kWh compared to Plant A at US$ 0.86/kWh. It was noted that the impact of capital costs, operating expenses, and revenue variations is less pronounced at larger scales. The findings from this study shed light on the feasibility of biomass gasification for power generation as a viable option, thereby unlocking the potential for its large-scale commercialization. [ABSTRACT FROM AUTHOR]

N-methyl pyrrolidone (NMP) is an important organic compound that is widely used in many industrial fields. Due to its volatility and toxicity, the detection of NMP content becomes crucial. Plasma treatment is an efficient method that utilizes high-energy ions generated by plasma to change the surface properties of materials, which can dramatically improve the performance of gas sensors. In this paper, ZnO nanorods were in-situ grown on ceramic tubes via hydrothermal method, followed by oxygen plasma treatment for different time, and the gas-sensing performance of the treated ZnO nanorods was investigated. In addition, the density functional theory calculation was used to explore the potential mechanism for the improvement of gas-sensing performance. The results show that ZnO treated with oxygen plasma for 60 s has more oxygen vacancies (45.53 %) and higher adsorption energy (−1.06 eV) to NMP. The ZnO-60 gas sensors have excellent selectivity to 100 ppm NMP at 210 °C, with a response value up to 197.58, low detection limit (94 ppb), and short response/recovery time (75 s/27 s). This study not only provides important theoretical and experimental basis for further optimizing the design and manufacture of gas sensors, but also provides strong support for environmental monitoring and human health protection. [Display omitted] • ZnO nanorods were prepared on the ceramic tubes by in-situ growth method. • Oxygen plasma treatment was used to improve the content of oxygen vacancies (45.53 %) for ZnO nanorods and the high gas-sensing response (S r = 197.58) to NMP with a detection limit of 94 ppb was achieved. • The adsorption energy, charge density difference, and density of states of NMP on the surface of ZnO materials were simulated and calculated by the DFT study to verify the potential mechanism for improving gas-sensing performance. • The sensors exhibit high selectivity and stability with short response/recovery time. [ABSTRACT FROM AUTHOR]

Occupational health and safety are the most valuable assets for any firm. The hazards that may occur in the workplace should be analysed and studied to minimize the possibility of their incidence. WMSDs (Work-related Musculo Skeletal Disorders) injuries are one of the most common accidents that happen in the workplace in some countries exceeding 40% of the total types of accidents. Thus, many techniques like REBA were innovated to analyse the risks leading to these kinds of injuries. This article studies and analyses 15 postures ergonomically in detail to cover all the working stations in a Gas Springs factory in Türkiye. This high number of postures with real-life cases from a developing country such as Türkiye can be considered an essential contribution to this field. Classical REBA and the REBA calculator are used in the application as tools and methods. Additionally, a comparison between REBA results with RULA and OWAS results for each posture is provided. The application showed that 53.33% of the postures' results were medium-level risks. This percentage displays that the workers aren't at a very dangerous risk level, but executives still should take action to reduce the risk level. This study aims to understand REBA and its importance. The article also shows how to apply Classical REBA step by step and how to use the REBA calculator. Finally, the outputs of this article should be beneficial practically and theoretically. It would be practical for the factory to develop the working stations according to the suggestion and theoretically for researchers to build new studies on it. [ABSTRACT FROM AUTHOR]

In existing power devices, various insulating parts are manufactured with petroleum-based epoxy resin. However, as petroleum-based resources are gradually depleted and environmental problems have emerged, research on replacing petroleum-based products with eco-friendly materials as insulators has been actively conducted. Therefore, in this study, a molding simulation study of the Auto Pressure Gelation (APG) process, one of the leading technologies, was conducted to manufacture a gas insulated switchgear (GIS) spacer using an environmentally friendly bio-based epoxy composite. Using the heat dissipation and degree of cure obtained through the dynamic differential scanning calorimetry (DSC) test, it was applied to the Kamal-Sourour model which is a representative curing dynamics empirical formula. In addition, the viscosity change during the curing process was measured using a rheometer and applied to the cross Castro-Macoskco model. The results obtained were in good agreement with the experimental values. The parameters calculated above and other physical property values were input into Moldflow software, and simulation was performed targeting the three-phase spacer. While changing the temperature setting of the mold, the change and distribution of flow, temperature, and curing degree inside the product were observed during the reactive molding process. As a result, it was found that there was a possibility of clogging of the mold entrance at some set temperatures, and it was possible to suggest improvement directions to solve this problem. Through this series of research process, it is considered that it will be of great help in improving the quality problems of molded products and the process accordingly. [ABSTRACT FROM AUTHOR]

The article discusses the mid-nineteenth-century introduction of gas production technology by the Deutsche Continental-Gas-Gesellschaft to the emerging cities in the area of the former Polish Lithuanian Commonwealth, namely Warsaw, Lviv, and Kraków. During the 1870s and 1880s, the local governments of Kraków and Lviv, dominated by Polish influences, sought to portray themselves as agents of modernization. Consequently, the arrival of a German investor implementing unfamiliar gas production technology was unwelcome. This resulted in the takeover (in Lviv) or buyout (in Kraków) of the gasworks in operation. In contrast, Warsaw, under the administration of Russia, reached an agreement with the concessionaire. Modernization of the gas industry in these cities commenced in the late nineteenth century, with management falling under both municipal (Kraków and Lviv) and private (Warsaw) entities. This allowed for the expansion of the gasworks and a subsequent increase in gas consumption, as facilitated by the reduction in the product’s price. However, Kraków and Lviv managed to present themselves as the architects of this favorable situation. Meanwhile, the authorities in Warsaw permitted the Dessau company to operate within the city, which engendered discontent among the Polish intelligentsia in the early twentieth century. In Germany and the Habsburg monarchy, it was customary for cities to municipalize their gasworks, with the profits channeled back into city budgets. This aspect of urban modernity, as it was perceived at the time, was absent in Warsaw.

The key natural cause of irradiation in humans is the air. People spend most of their time at home, so home is likely a main source of natural radionuclide exposure in the air, especially radon gas. It is the second cause of lung cancer after smoking. This study aims to evaluate Radon‐222 gas (222Rn) concentrations in the houses (indoor dwellings) of the Al‐Hussainya district of the Karbala Governorate, Iraq. Also, some radiological parameters such as AED (annual effective dose), PAEC (potential alpha energy concentration), EP (exposure to radon progeny), and CPPP (lung cancer cases per year per million people) were calculated. 222Rn concentrations were determined using closed and open dosimeters with CN‐85 detector (thickness of 12 μm). The range and average of 222Rn concentrations were from 21.791 Bq/m3 to 43.376 Bq/m3 and 32.3381 Bq/m3 in open dosimeters, respectively. While in closed dosimeters, the range of 222Rn concentrations and average values were from 19.324 Bq/m3 to 37.286 Bq/m3 and 26.6462 Bq/m3, respectively. The average values of AED, PAEC, EP, and CPPP due to radon by open dosimeters were 0.083 mSv/y, 0.358 mWL, 14.759 mWLMY−1, and 1.503, respectively, while the average values of AED, PAEC, EP, and CPPP due to radon by closed dosimeters were 0.063 mSv/y, 0.270 mWL, 11.134 mWLMY−1, and 1.134, respectively. According to WHO, EPA, and ICRP, the values of radon concentrations were within the range of what was allowed internationally. Also, the results of the radiological parameters due to radon gas for the study of the houses of the Al‐Hussainya district of the Karbala Governorate, Iraq, were low and did not constitute a health hazard. [ABSTRACT FROM AUTHOR]

Direct current (DC) and pulsed DC tungsten inert gas (TIG) additive manufacturing processes were employed to fabricate GH4169 high-temperature alloy specimens. Upon comparing and analysing the two additive manufacturing methods, the evolution of microstructure and mechanical properties of the additively manufactured specimens were discussed. It provided a useful reference for the engineering application of pulsed DC TIG technology. The results showed that the overall forming process of the specimen was relatively stable under the DC TIG additive manufacturing and pulsed DC TIG additive manufacturing processes. The aspect ratio of the deposited layer of the pulsed DC-deposited specimen was relatively low, and the deposited layer of the pulsed DC specimen became flatter, which was conducive to maintaining the stability of the molten pool during the deposition process and improving forming accuracy. The microstructure distribution of the deposited layer from bottom to top was relatively uneven, with columnar dendrites in the bottom layer, cellular crystals in the middle layer, and equiaxed crystals in the top layer. Compared with the DC TIG additive manufacturing of GH4169 high-temperature alloy specimens, the Laves phase of the pulsed DC specimens was significantly reduced, which improved the plasticity and brittleness of the material. [ABSTRACT FROM AUTHOR]

Copyright of China Mining Magazine is the property of China Mining Magazine Co., Ltd. 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.)

Triethylamine (TEA) is a typical volatile organic compound (VOC) widely present in air and water, produced in industrial production activities, with high toxicity and great harm. Fluorescence detection and resistive sensing are effective methods for detecting pollutants. Here, In-doped interpenetrating twin ZIF-8 and its annealed derivatives have been successfully designed and prepared as a multifunctional TEA sensor. On the one hand, ZIF-8-In exhibits excellent fluorescence emission enhancement at 450 nm in a dose-dependent manner to TEA in water within the concentration range of 1–100 ppm, with a detection limit as low as 1 ppm. On the other hand, the annealed ZIF-8-In derivative is ZnO/In2O3 with a porous hierarchical structure, which is a perfect sensitive material for manufacturing gas sensors. Within the concentration range of 1–100 ppm, the ZnO/In2O3 gas sensor has a high response for 100 ppm TEA, reaching 107.7 (Ra/Rg), and can detect TEA gas as low as 1 ppm. Furthermore, the response of ZnO/In2O3 sensors to TEA is at least 10 times that of the other four VOC gases, demonstrating excellent gas selectivity. This multifunctional sensor can adapt to complex detection situations, demonstrating good application prospects. [ABSTRACT FROM AUTHOR]

The paper focuses on magnetron sputtering of the pure calcium target in DC magnetron discharge. The target diameter and thickness are 50 and 3 mm, respectively. Argon and krypton are used as working gases. Continuous and medium frequency discharges are investigated along with the discharge and plasma parameters, including a current–voltage characteristic, mass-to-charge ratio of the plasma composition, ion current, and deposition rate. [ABSTRACT FROM AUTHOR]

Mars has nearly ideal conditions for CO2 dissociation by glow discharge plasmas. The directly generation of O2 and CO on Mars was considered to be feasible and practical for in situ resource utilization of Martian atmosphere to get respirable O2 and fuel. In this paper, we conduct several experiments under simulated Martian conditions to investigate the process and how the key parameters effect the generation of O2 and CO in CO2 glow discharge reactions. The yields of new products (i.e., O2 and CO) under various gas discharge work parameters (i.e., discharge power, frequency, voltage, gap between the discharge plane electrodes and gas pressure) were systematically investigated. The reaction mechanism and reaction path of CO2 glow discharge has been discussed. In our study the max yield of O2 by CO2 discharge dissociation was got about 21.8 g/h at 168 W which is very close to that of NASA MOXIE (Mars Oxygen In-Situ Resource Utilization Experiment) at the same power. Our results showed the great potentiality of glow discharge for the practicable technology of O2 and CO generation for in-situ resource utilization on Mars. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effects of different catalysts on biomass gasification. Therefore, red mud (RM) and Aluminum–Nickel alloy were used as catalysts with biomass mixture (BM) for the lab-scale gasification studies by using an updraft and a modifiable-downdraft fixed bed reactor. The maximum volumetric percentage of H 2 , ranging from 51% to 65%, was achieved at 900 °C in both gasifiers. Al–Ni catalyst significantly boosted H 2 content, reaching 65% in the updraft gasifier at 900 °C with 0.05 L/min dry air. H 2 /CO ratio varied from 2 to 4 for BM, while catalyst use expanded the range to 1.6–7 with the Al–Ni catalyst demonstrating the most effective performance. In general, it was seen that RM increased the H 2 component in the syngas between 1 and 7 vol% at 900 °C in updraft gasifier. In the modifiable-downdraft reactor, on the contrary, H 2 concentration in the syngas decreased by 2–6% with the addition of RM. [Display omitted] • Red mud and aluminum - nickel alloy were added to biomass as catalysts. • Two different fixed-bed gasifiers were operated under the same conditions. • The use of the catalyst increased the H 2 vol% in the syngas. • The max. volumetric percentage of H 2 gas was found to be in the range of 51–65%. [ABSTRACT FROM AUTHOR]

In recent decades, growing energy demand, coupled with concerns about climate change, has led to the exploration of sustainable energy sources. Among these, biomass gasification stands out as a promising method for generating heat and power. This research delves into the potential impact of biomass gasification within the global energy landscape, focusing particularly on its application in cogeneration plants. Utilizing Aspen Plus software V10, this study undertook the modeling and optimization of a biomass cogeneration plant. Through simulation, it was found that a biomass flow rate of 5 kg/s yielded 6.172 MW of power output. Additionally, the study revealed several key factors that influence power generation: increasing biomass and airflow rates, increasing gasification temperature, and reducing water flow rate. By doubling the biomass flow rate to 10 kg/s and increasing the temperature to 800 °C, power generation increases by 41.75%. Moreover, the study demonstrates that Portuguese municipal waste is an efficient source of energy production, with higher cold gas and overall efficiencies compared to forest and vine-pruning residues. [ABSTRACT FROM AUTHOR]

In order to improve the comprehensive utilization efficiency of coal and natural gas resources in northern Shaanxi, optimize the composition of syngas, and couple the reaction heat, a pilot-scale study of coal and natural entrained flow co-gasification technology was carried out on the basis of the previous research. The construction scale and process flow of the coal and natural gas co-gasification pilot plant were introduced, and the long-term operation stability of the unit was investigated during the test, and the effects of gasification pressure, operating load and natural gas to coal ratio on the co-gasification reaction were explored. It is believed that under stable operating conditions, coal-natural gas co-gasification can reduce raw material consumption and carbon dioxide emissions at the same time, which has certain technical advantages compared with traditional coal-water slurry gasification. [ABSTRACT FROM AUTHOR]

The article discusses the mid-nineteenth-century introduction of gas production technology by the Deutsche Continental-Gas-Gesellschaft to the emerging cities in the area of the former Polish-Lithuanian Commonwealth, namely Warsaw, Lviv, and Kraków. During the 1870s and 1880s, the local governments of Kraków and Lviv, dominated by Polish influences, sought to portray themselves as agents of modernization. Consequently, the arrival of a German investor implementing unfamiliar gas production technology was unwelcome. This resulted in the takeover (in Lviv) or buyout (in Kraków) of the gasworks in operation. In contrast, Warsaw, under the administration of Russia, reached an agreement with the concessionaire. Modernization of the gas industry in these cities commenced in the late nineteenth century, with management falling under both municipal (Kraków and Lviv) and private (Warsaw) entities. This allowed for the expansion of the gasworks and a subsequent increase in gas consumption, as facilitated by the reduction in the product's price. However, Kraków and Lviv managed to present themselves as the architects of this favorable situation. Meanwhile, the authorities in Warsaw permitted the Dessau company to operate within the city, which engendered discontent among the Polish intelligentsia in the early twentieth century. In Germany and the Habsburg monarchy, it was customary for cities to municipalize their gasworks, with the profits channeled back into city budgets. This aspect of urban modernity, as it was perceived at the time, was absent in Warsaw. [ABSTRACT FROM AUTHOR]

To comprehensively understand the influence of mining speed on gas emissions in goaf during coal seam extraction, enhance gas extraction efficiency in goaf, manage gas emissions at the working face, and ensure safety in the mining production process. This study focuses on the No. 3 mining area of Wangjialing Mine, employing numerical simulations to analyze the evolution of mining-induced fractures and the characteristics of gas distribution in the overburden at varying mining speeds. Furthermore, by integrating actual gas emission and extraction data at the production face, this study examines the quantitative relationship between mining speed and gas emissions in the goaf, identifying optimal regions for high-position borehole layouts and conducting borehole optimization design and investigation. The results of this study indicate that the initial caving step distance of the goaf roof increases with the advancement speed of the working face. Conversely, the maximum height of through fractures in the overburden decreases as the mining speed increases, while delamination fractures are minimally affected by the advancement speed. By categorizing and averaging data on goaf mining speed, the impact of initial and periodic pressure on gas emissions can be effectively mitigated, revealing a linear correlation coefficient of 0.94 between goaf gas emissions and mining speed. At varying mining speeds of the working face, the efficient extraction layer and horizontal distance parameters of gas extraction boreholes in the goaf conform to the linear equation y = ax ± b. Based on the research findings, an optimization design for mining face speed and high-level borehole parameters in the goaf was implemented. The average gas extraction rate of high-level directional boreholes reached 68% throughout the extraction period. Gas emissions at the working face were effectively controlled below 10 m3/min, with the maximum gas concentration at the upper corners and return airflow kept below 0.8%. This effectively managed gas emissions at the working face, ensuring safe production in the mine, providing a theoretical basis for identifying gas-rich areas in the mining-induced overburden, and enhancing gas extraction efficiency at the working face. [ABSTRACT FROM AUTHOR]

Copyright of AIN Journal is the property of Arab Institute of Navigation 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 article describes possible failures that may occur during the operation of boilers and installations operating with natural gas. The possibilities of determining these refusals and the reasons for their occurrence are considered. Information is given to control and manage the risks leading to these failures, as an opportunity to predict their occurrence and create a basis for their dissipation or elimination in order to ensure the safe operation of boilers and installations working with natural gas. [ABSTRACT FROM AUTHOR]

Accurately identifying the Bottom Simulating Reflector (BSR) is a crucial and fundamental task in seismic exploration and the interpretation of gas hydrates in marine areas. During our seismic interpretation and inference work on a gas hydrate survey in the Qiongdongnan Sea area, we encountered a phenomenon that closely resembled the seismic reflection characteristics of BSR. By comparing and identifying various geological phenomena, we have determined that this unique seismic reflection phenomenon is, in fact, the reflection of the depositional bottom interface known as "mass transport deposits (MTDs)" as described by previous researchers. The physical properties of the MTDs developed on the shallow surface of the seafloor are similar to those of gas hydrate reservoirs in the seismic exploration of marine areas, particularly in the northern South China Sea's Qiongdongnan Sea area. Due to the lack of active neotectonic movement in the area, most identified BSR reflection occurrences are parallel to the seafloor. Consequently, during the process of seismic interpretation of BSR in the Qiongdongnan Sea area, it may be confused with the bottom boundary reflection interface of MTDs. Accurately identifying MTDs' sedimentary bodies in gas hydrate exploration activities in this area would greatly enhance the accurate identification of BSR and support the refined evaluation of gas hydrate resources. In this paper, the structural characteristics of MTDs are compared with the reflection characteristics of seismic profiles, the reflectors are identified as MTDs rather than BSR through analysis and interpretation, and the possible mechanism of hydrate accumulation in this region is discussed. [ABSTRACT FROM AUTHOR]

In the industrial gas manufacturing sector, stringent safety protocols and proactive safety promotion are crucial to prevent hazardous incidents protect employees, customers, and the environment from the potential risks of handling and transporting these gases. Train The Trainer (TTT) programmes can be tailored to the organisation's needs and cover various topics, such as handling hazardous materials, emergency response procedures, equipment use and ergonomics, and managing emergency response procedures. The B-SAFE project, designed based on the 'Communities of Practice' theoretical framework and adopting the TTT approach, aims to provide workers with tools and resources to increase work safety and reduce accidents by acting on underlying cognitive behaviour and processes. The present case study aims to present the Italian adaptation of the B-SAFE training programme, incorporating specific revisions resulting from previous research. Twenty-five Health, Safety and Environment (HSE) top and middle managers from a leading gas manufacturing firm participated in the five-module training. At the conclusion of each B-SAFE module, they filled out a short questionnaire to report their satisfaction with the training methods and content. The answers were analysed to gather feedback on the course. In general, participants found the course to be useful, satisfying, fun and easy. [ABSTRACT FROM AUTHOR]

Despite the high abundance and potential toxicity of ferrocyanide in the environment, data on the bioremediation of these complexes in contaminated soils are missing. In this study we isolated forty bacterial species presented in soil highly contaminated with ferrocyanide complexes, originating from a Manufactured Gas Plant (MGP). All bacterial strains were resistant to ferrocyanide (500 mg L−1). Six isolates showed better growth in the presence of ferrocyanide and were able to use it as a sole nitrogen source. One of them was able to assimilate ferrocyanide‐derived nitrogen and carbon. The strains varied in their tolerance to the ferrocyanide. The Minimum Inhibitory Concentration (MIC) values determined in the rich medium ranged from 1400 mg L−1 to 2000 mg L−1 and in all cases were greater than those set on the minimal medium. Molecular analysis revealed that the investigated isolates had the highest similarity to the Bacillus and Rummeliibacillus lineages. Rummeliibacillus was recognized for the first time for its ferrocyanide-degrading potential. Soil samples collected from MGP sites indicated that the overall indigenous population of microorganisms was low. Total cyanide content ranged from 220 mg kg−1 to 346 mg kg−1. Additionally, elevated Pb concentrations and an imbalanced C:N:P ratio were observed. Our study provides new information about the presence of a well-acclimated bacterial community associated with long-term ferrocyanide-contaminated soil. This bacterial community could play an important role in MGP site bioremediation processes and has the potential for application for other bioremediation purposes; however, it is likely limited due to unfavorable environmental conditions. [ABSTRACT FROM AUTHOR]

Poor condition of roofs in terms of decay of shingles and loss of tar-based surface treatments has been revealed in a number of churches at various geographical locations in mid-Sweden. The condition of tars obtained from shingles of selected churches in mid-Sweden were analysed and obtained data were compared with geographical locations of the churches. According to gas chromatography-mass spectroscopy result, dehydroabietic acid was the dominant compound found in the exposed tars from the churches except in church of Malung where similar amounts of retene was found. Oxidised resin acids were found in exposed tars from the churches but not in commercially available pit burned tar. Tar from church shingles had higher char residues than the pit burned tar which was totally consumed when heated under nitrogen gas up to 750°C using thermogravimetric analysis. Scanning electron microscopy with energy dispersive X-ray spectrometer analysis revealed higher amounts of silicates in some exposed tars; however, these compounds constituted only a minor portion of the organic matter in these specimens. Based on the data obtained in the study other factors rather than simply geographical location of churches seemed to be of importance to explain differences of the investigated properties of the church tars. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) is a greenhouse gas produced in the manufacture of 6,6‐nylon and nitric acid. While an attractive oxidant that releases only N2 as a by‐product, the kinetic stability of N2O typically requires high temperatures and pressures for activation. This work describes initial kinetics of oxygen transfer in the epoxidation of cholesteryl acetate with N2O catalysed by D4‐Ru(VI)(por)(O)2 complexes in efforts to provide a better mechanistic understanding of this chemistry. Insights include a need for low concentrations of the alkene to avoid competitive binding to the metal, possible saturation behavior at high N2O pressures, transfer of only one oxygen of RuVI(O)2 to substrate and a possible catalyst turnover involving disproportionation of RuIV(O) and RuIV(O)(N2O) to active RuVI(O)2, RuIV(O) and N2. These insights will be used in future designs of improved catalysts and reaction protocols that may operate efficiently at low pressures of N2O and ambident temperature. [ABSTRACT FROM AUTHOR]

Multi-laser Additive Manufacturing systems hold great potential to increase productivity. However, adding multiple energy sources to a powder bed fusion system requires careful selection of a laser scan and inert gas flow strategy to optimize component performance. In this work, we explore four different laser scan and argon flow strategies on the quasi-static compressive mechanical response of Body Centered Cubic lattices. Three strategies employ a swim lane method where laser pathing tends to progress parallel to argon flow. Method one only uses a single laser while method two uses four, both with the laser path working against the argon flow. The third method uses four lasers, each operating in their own lane like the second method, but the laser pathing progresses with the argon flow. The fourth method has all four lasers operating in quadrants and the laser pathing trends against the argon flow. The single-laser strategy generally had the lowest mechanical responses compared to the other three strategies. A quadrant strategy generally had the highest quasi-static mechanical responses and was at least 25% greater in stiffness, yield force, ultimate force, and energy absorption when compared to the single laser strategy. However, the four-laser swim strategy where the laser pathing tends against the argon flow was found to be statistically similar to the quadrant strategy. It is hypothesized that spatter introduced onto the powder layer from the melt pool and particle entrainment may be worse for laser pathing which trends with the argon flow direction. Additionally, the additional energy added to the build volume helps to mitigate inter-layer cool time which reduces temperature gradients. This shows that multi-laser AM systems have an impact on part performance and potentially shows lattices built with multi-laser AM systems may have certain advantages over single-laser AM systems. [ABSTRACT FROM AUTHOR]

Oxide dispersion-strengthened (ODS) superalloys are usually manufactured by a hot isostatic pressing after mechanical alloying (MA-HIP). However, this process cannot produce complex-shaped parts. Here, we used an additive manufacturing product (powders produced by laser powder bed fusion, L-PBF) to address this issue. Modified ODS Ni-based superalloy powders with a similar composition to the mechanical alloy 6000 (MA6000) were manufactured using a gas atomization process. The obtained powders and L-PBF synthesized samples were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), LPSA, and EBSD analyses. [ABSTRACT FROM AUTHOR]

Considering Malaysia's position as a leading producer of palm oil, it wastes appears to be a promising renewable energy source. Thus, present work compares optimal behavioural performance and power generation potential from the palm oil mill wastes, including empty fruit bunch (EFB) and palm kernel shell (PKS). Aspen Plus software is used to perform a sensitivity study, investigating the influence of temperature and equivalence ratio (ER) on syngas output, syngas composition, and power generation. Temperature increase (600◦C to 1000◦C) leads to increase in H2 and CO and decrease in CO2 and CH4 composition. At optimal operating condition, temperature for EFB and PKS is at 740◦C and 865◦C while ER is at 0.25 for both feedstocks. The low heating value (LHV), cold gas efficiency (CGE) and total syngas output happens to be around 4.84 MJ/Nm3, 48.89% and 259.18 kg/hr for (EFB and 4.01 MJ/Nm3, 51.27 % and 312.97 kg/h for PKS. EFB shows higher capability to produce more quality syngas and generate more power compared to PKS. From economic perspective, EFB brings more revenue (115 million/year) than PKS (111 million/year) for 10 MW plant capacity by considering electricity as the main product. [ABSTRACT FROM AUTHOR]

The study aims to address the physical properties and chemical composition of ash and slag waste from a thermal power plant to determine the possibility of its reuse in the heat and power industry. This included classification and chemical analysis of ash and slag waste generated by the Bishkek thermal power plant to determine its composition. The received material samples were also subjected to laboratory tests to determine the particle size distribution and moisture content. Once the fractionation boundaries were established, a detailed study of the ash mass was carried out, including carbon distribution analysis and flotation experiments to determine effective methods of carbon recovery from ash and slag waste. The results confirmed the significant potential of ash and slag waste from the Bishkek coalfired thermal power plant for reuse in the heat and power industry. Analysis of the chemical components revealed the content of unburned coal particles within 10-11%, and the content of water-soluble sulphur and sulphuric acid compounds ranged from 0.18% to 0.71%. Experimental data confirmed the importance of the fractionation of ash and slag by particle size, which makes it possible to further separate coal fractions with different physical properties. The fraction of less than 150 microns is characterised by a low carbon content (less than 2.5%), which makes it suitable for use in construction as a fine aggregate. However, the study noted that fractions larger than 150 microns, and especially those larger than 300 microns, are a valuable feedstock for the production of carbon concentrate with a carbon content of more than 75%, which opens up the prospects for its use in the production of water-coal fuel. Thus, the results of the study confirm the potential of ash and slag waste for reuse in the heat and power industry. This can help to reduce waste, reduce the negative impact on the environment, and create efficient and sustainable production processes in the heat and power industry. [ABSTRACT FROM AUTHOR]

The generation and accumulation of coal gangue (CG) and coal slime (CS) are a serious cause of environmental pollution. The co-pyrolysis of CG/CS and pine sawdust (PS) is an effective method to reduce pollution and waste generation. In this work, the co-pyrolysis characteristics of CG/CS and PS were analyzed by the thermogravimetric analyzer and fixed bed pyrolysis reactor. The kinetics analysis showed that the activation energies decreased with the PS mixing ratio increased for CG/PS blends and CS/PS blends in the second pyrolysis stage. The synergistic effect on yield is quantified by comparing the results of the co-pyrolysis of CG/CS and PS blends with weighted results from the pyrolysis of CG, CS and PS individually. The results revealed that when the mixing ratio of CG:PS was 1:1, the difference between the experimental and calculated yields (2.9 %) and the H 2 yield (320 ml/g) were maximum. Among the CS/PS blends, these values are maximum when the mixing ratio of CS:PS is 3:1 (2.5 % and 450 ml/g). Furthermore, the alkali and alkaline earth metals K and Ca in the co-pyrolysis char catalyze the decomposition of the –OH functional group. • CG/CS and PS co-pyrolysis was studied by non-isothermal and isothermal conditions. • The alkali and alkaline earth metals in the co-pyrolysis char had a catalytic effect. • CG/PS1-1 and CS/PS3-1 mixing ratio had the highest hydrogen yield. [ABSTRACT FROM AUTHOR]

The depletion of fossil fuels such as oil, natural gas, and coal, as well as environmental concerns, pave the way for the effective utilization of renewable energy sources. Hydrogen is forecasted as an energy alternative which can be utilized at high conversion causing zero or near-zero emission at the point of use. Methanol is an ideal hydrogen carrier owing to its low cost, high H/C ratio, low reforming temperature, no sulfur content and liquid state at ambient conditions and it can be produced from a variety of feedstocks. This review article provides an overview of the various catalysts employed in steam reforming of methanol (SRM). It delves into the effect of catalyst preparation methods and catalyst composition on the catalytic activity and selectivity for SRM. Thermodynamic analysis, the reaction schemes and kinetics over various catalysts used in SRM were discussed in detail. Various reactors used for SRM, including conventional packed bed, microchannel and membrane reactors were thoroughly reviewed and discussed. • Various hydrogen production methods are presented. • Thermodynamic analysis of SRM is summarized. • Performances of Cu and Pd based catalysts on SRM are reviewed. • Various reactor configurations used in SRM are summarized. • Reaction mechanisms and Kinetic expression for SRM are tabulated. [ABSTRACT FROM AUTHOR]

Plastic pollution is a generational problem, and stakeholders are turning to chemical recycling as a potential solution. However, decision‐makers necessitate quick and reliable capital investment estimations to evaluate innovative technologies, especially in the early project stage, when limited historical data are available. To address this need, we built a database of 160+ chemical recycling plants, querying for nominal capacity, year and place of construction, total capital investment (TCI), number of long‐term jobs and opportunity of subsidies. Then, we compared conventional association of the advancement of cost engineering AACE class 5 estimation methods, with literature estimates, and commercial capital expenditure confidence intervals for pyrolysis, gasification, solvolysis, and selective dissolution. We demonstrate the unreliability of classic methods, and we propose ballpark correlations based on the plant capacity, or the energy loss. Chemical recycling plants suffer from poor economy of scale (with current technologies), and capacity is not always the best indicator for TCI estimation. Pyrolysis and gasification are energy‐driven technologies, and their TCI correlates very well (R2=0.91–0.92) with the total energy losses. Solvolysis and selective dissolution, instead, are at an earlier development stage, so cost engineers or researchers will have to accept less certain TCI vs capacity (R2=0.60). [ABSTRACT FROM AUTHOR]

Recent research advances and technological developments of spouted bed reactors (SBRs) have been discussed in this work. SBR has aroused increasing interest since their invention in 1955 due to its flexibility in processing different feedstocks and the high process yields that can be achieved due to its characteristic fluid dynamics. However, even though highly satisfactory results have been obtained at the laboratory scale for different applications (i.e., drying or thermochemical reactions, among others), their full implementation at an industrial level is still scarce, mainly due to the challenges encountered for their scale-up. In this work, an initial short description of SBR and configurations is followed by a review of the main experimental activities that have been conducted at different scales in the period 2013–2023. Advanced solutions such as multi-unit reactors and the use of rectangular geometries instead of the classical cylindrical ones have arisen as potential areas for further study and development to achieve a reliable implementation of the spouted bed technology at an industrial scale. [ABSTRACT FROM AUTHOR]

The formation of boreholes in tectonically deformed coal (TDC) seams is challenging, hindering the efficient exploitation of coalbed methane (CBM) resources. The reciprocating multi-stage reaming drilling technology presents a promising solution for realizing the formation of horizontal wells in TDC seams that are broken, high-pressure, and collapse-prone. To investigate it, an engineering-geological model was established to conduct physical simulation tests of multi-stage reaming drilling in horizontal wells of the TDC seams using the 11–2 TDC seam of Zhangji Mine in the Huainan Mining District as the geological prototype. Reformed tectonic coal was used to simulate the natural stratum, and drilling parameters were recorded. The test obtained a 110 mm borehole to simulate the reality of 550 mm, and the final hole was 284% of the initial one, which achieved the target and completed the design requirements. During the process, the drilling thrust force and drilling speed remained stable, while the torque increased progressively, and the unsupported borehole wall remained intact after completion. The laboratory results demonstrate that the reciprocating multi-stage reaming drilling technology can be applied in TDC seams. Highlights: The multi-stage reaming drilling technology improves coal methane resource exploitation by forming horizontal wells in tectonically deformed coal seams. Engineering-geological model, simulation tests using samples of tectonic coal confirm technology's suitability for tectonic coal seams. Completed experimental simulation of multi-stage reaming drilling in the laboratory to provide a reference example for field drilling. [ABSTRACT FROM AUTHOR]

The practical application of formic acid production through the hydrogenation of CO2 has garnered significant attention in efforts to tackle the challenges associated with (1) achieving net-zero production of formic acid as a chemical feedstock and (2) improving hydrogen storage and transport. This study focuses on demonstrating the continuous operation of a trickle bed reactor for converting CO2 into formate using palladium on activated carbon (Pd/AC). Optimal temperature conditions were investigated through a dynamic operation for 24 h, achieving the maximum productivity of 2140 mmolFA·gPdsurf.−1·h−1 at 150 °C and 8 MPa, with an H2/CO2 ratio of 1:1; however, catalyst deactivation was observed in the process. Stability tests performed under continuous operation at 120 °C and 8 MPa with an H2/CO2 ratio of 1:1 indicated a gradual decline in productivity, culminating in a 20% reduction after 20 h. A comprehensive analysis comparing fresh and spent catalysts revealed that the diminished catalytic activity at elevated temperatures was attributed to the partial sintering and leaching of Pd nanoparticles during the hydrogenation process. These findings offer insights for the future development of novel Pd-based catalyst systems suitable for continuous hydrogenation processes. [ABSTRACT FROM AUTHOR]

Energy and environmental challenges are a major concern across the world and the urban residential building sector, being one of the main stakeholders in energy consumption and greenhouse gas emissions, needs to be more energy efficient and reduce carbon emissions. While it is easier to design net zero energy homes, existing home stocks are a major challenge for energy retrofitting. Two key challenges are determining the extent of retrofitting required, and developing knowledge-based effective policies that can be applied en-masse to housing stocks and neighborhoods. To overcome these challenges, it is essential to gather critical data about qualities of existing buildings including their age, geo-location, construction type, as well as electro-mechanical and occupancy parameters of each dwelling. The objective of this study was to develop a GIS-based model embedded with critical data of residential buildings to facilitate evidence-based retrofit programs for urban neighborhoods. A model based on a bottom-up approach was proposed in which information gathered from all stakeholders was inputted into one database that can be used for decision-making. A geo-located case study to validate a proposed GIS-based residential retrofitting model sample size of 74 residential buildings in the city of Riyadh was statistically analyzed and used. The results indicate behavior-based patterns, with a strong positive correlation (r = 0.606) between the number of occupants and number of household appliances, while regression analysis showed high occupancy rates do not necessarily result in high utility costs at the end of the month, and there is no statistical difference in the average monthly cost of gas between partial and fully occupied houses. Furthermore, neither the type of building, height, age, nor occupancy status play a significant role in the average energy consumed. Additionally, the GIS-based model was validated and found to be effective for energy-use mapping and gathering critical data for analyzing energy consumption patterns at neighborhood scale, making it useful for municipalities to develop effective policies aimed at energy efficient and smart neighborhoods, based on a recommended list of most effective energy-saving retrofit measures. [ABSTRACT FROM AUTHOR]

We have developed a container system for in-situ measurement of CO2 and CH4 that significantly reduces the consumption of working standard gases to a level less than one order of magnitude smaller than that required by a common method. It uses on-site compressed air to track the baseline drift of sensors. JR-STATION (Japan-Russia Siberian Tall Tower Inland Observation Network) consisted of this system installed at nine sites in Siberia. The system acquires semi-continuous data by recording several minutes of averaged data after gas replacement time. We have updated the calculation method for deriving CO2 and CH4 concentrations to determine their uncertainty for each data simultaneously. Furthermore, we estimated the system's reproducibility based on the repeated measurement of on-site compressed air. The CO2 and CH4 concentration reproducibility mostly varied by less than 0.2 ppm and five ppb, respectively. Uncertainties of time-averaged data were sometimes higher than the measurement uncertainty for each period, suggesting that the data include atmospheric variability during the measurement period of several minutes. Data users should consider the difference between the two uncertainties to select optimal data, depending on their focusing spatial scale. The CO2 and CH4 data measured with the NDIR and the tin dioxide sensor exhibited good agreement with those measured by the CRDS, respectively. [ABSTRACT FROM AUTHOR]

In this paper, the combustion behavior of the syngas/air mixture in a narrow gap disk reactor were explored. Besides, the influence of the hydrogen volume fraction and the mixture equivalence ratio in syngas on the property of propagating flames were investigated in the narrow gap disk reactor under the gap thicknesses of 8 mm, 6 mm, 4 mm, 3 mm, and 2 mm, respectively. The focus was placed on the behavior of the flame propagation under the gap thickness of 2 mm. The research results demonstrated that the increase of the hydrogen volume fraction from 5 % to 30 % exerted a significant impact on the flame propagation velocity (FPV) and the pressure in the tube. Moreover, the equivalence ratio of this mixture could markedly affect both the propagation characteristics and morphology of flames. Strong flame instabilities accompanied by pressure oscillations were observed in the reactor at a 2 mm gap thickness during the later stages of flame propagation. Notably, there were significant differences in unstable combustion behavior between different syngas components. Moreover, the combined action of heat losses and compression waves leads to significant flame instability. The insights gained from this study have practical implications in various production applications. For example, optimizing hydrogen volume fraction and mixture equivalence ratios can enhance combustion efficiency and reduce pressure fluctuations in industrial reactors, leading to improved energy utilization and reduced environmental emissions. • The combustion characteristics of syngas in a narrow gap disk reactor were studied. • Hydrogen content affects flame propagation but has little effect on cell structures. • The syngas/air mixture equivalence ratio affects the flame cell structure. • Strong instability manifests when the flame propagates within a 2 mm gap thickness. [ABSTRACT FROM AUTHOR]

The exploration and development potential of shale gas reservoirs in the Sichuan Basin is enormous; however, it also faces difficulties such as complex structures, strong heterogeneity, and unclear geophysical response characteristics. Fine prediction of geostress is an important part of shale gas exploration and development, which directly affects the implementation effect of reservoir evaluation, well trajectory design, and fracture reconstruction. The existing geostress prediction techniques lack high-precision seismic data constraints, making it difficult to accurately reflect the planar distribution characteristics of geostress in the block with rapid changes in complex tectonic zones. At the same time, the geophysical response characteristics of geostress in the Sichuan Basin are unknown, and the geostress seismic prediction technology lacks theoretical basis. This paper combines numerical simulation and physical experiments and defines the characteristics of the geophysical response of shale gas reservoirs in the Sichuan Basin changing with the stress field, and technical countermeasures for geostress seismic prediction have been established to provide technical means for accurate prediction of the geostress field in the shale gas block. Based on the geostress sensitive parameters obtained from prestack seismic inversion, the geostress field prediction of a shale gas work area in the Sichuan Basin is realized. [ABSTRACT FROM AUTHOR]

A quantitative evaluation method for the magnesia refractory deterioration in the smelting process is proposed based on analysis of static and rotating finger tests to study the dissolution behavior. A transient 3D fluid-solid coupled numerical model was then developed, including the two-phase gas/slag flow pattern, temperature profile, MgO content distribution, solid refractory dissolution, and sample shape change. A kinetic degradation model was introduced to calculate the refractory overall wear rate determined by the coupled effect of the flow-induced erosion and chemical-induced corrosion. The shape change of the solid refractory sample was characterized via the dynamic mesh technique. A close correlation between the simulated results and the experimental data gives confidence in the fundamental validity of the developed numerical model. The results indicate that the flow would increase the overall wear rate by one or two orders of magnitude depending on the velocity. Therefore, flow-induced erosion must be accounted for in estimating the refractory wear rate. The flow-induced erosion and chemical-induced corrosion could be quantified via the wall shear stress and a modified Arrhenius's law, respectively. [ABSTRACT FROM AUTHOR]

Utilization of in situ/operando methods with broad beams and localized probes has accelerated our understanding of fluid-surface interactions in recent decades. The closed-cell microchips based on silicon nitride (SiNx) are widely used as "nanoscale reactors" inside the high-vacuum electron microscopes. However, the field has been stalled by the high background scattering from encapsulation (typically ~100 nanometers) that severely limits the figures of merit for in situ performance. This adverse effect is particularly notorious for gas cell as the sealing membranes dominate the overall scattering, thereby blurring any meaningful signals and limiting the resolution. Herein, we show that by adopting the back-supporting strategy, encapsulating membrane can be reduced substantially, down to ~10 nanometers while maintaining structural resiliency. The systematic gas cell work demonstrates advantages in figures of merit for hitherto the highest spatial resolution and spectral visibility. Furthermore, this strategy can be broadly adopted into other types of microchips, thus having broader impact beyond the in situ/operando fields. [ABSTRACT FROM AUTHOR]

The work is devoted to the development of a thermal scheme for the conversion of a cogeneration power plant to threegeneration with the production of hydrogen as a new product. The purpose of the work is to assess the possibility and potential of hydrogen production from MSW at the existing thermal power plants of St. Petersburg. To achieve this goal, it is necessary to develop a methodology for selecting the site of an existing thermal power plant in order to integrate a hydrogen production complex by the MSW gasification method, as well as a methodology for estimating the amount of hydrogen that can potentially be obtained from a given amount of MSW. The research methods include simulation of the thermal circuit of a steam power plant in the United Cycle program. The paper proposes an algorithm for selecting the site of an operating thermal power plant for the integration of a complex for the production of hydrogen by the method of MSW gasification. The algorithm can be applied to any subjects of the Russian Federation, and its relevance is confirmed by strategic documents. Potential locations for the new TPP are being considered in the territories of TPP-21 and TPP-22, which have the necessary resources and good infrastructure. As a result of the study, the site of TPP-22 was selected as the most suitable for the placement of new facilities. A new thermal scheme of a threegeneration power plant has been developed, including a hydrogen generation unit by the MSW gasification method. This allows the production of hydrogen in parallel with the production of electricity and heat. The efficiency evaluation criterion is the fuel heat utilization factor (FHUF). Regardless of the hydrogen content in the generated synthesis gas, the integration of the synthesis gas cooler into the thermal circuit of the TPP leads to an increase in the FHUF and an additional energy effect. This scheme increases the efficiency of existing TPP plants, regardless of the morphological composition of municipal solid waste. [ABSTRACT FROM AUTHOR]

Liquid Organic Hydrogen Carriers (LOHCs) feature a highly variable rate of hydrogen release if held at constant pressure and temperature, but in real-life applications hydrogen release must be controlled to match end-user demand. The aim of this paper is to provide an overall assessment of LOHC systems' controllability, within a general framework regardless of the specific application field. Hydrogen discharge can be controlled through the reactor pressure and temperature; thus, a PI controller is introduced acting on three control variables independently: discharge pressure; thermal fluid inlet temperature; thermal fluid mass flow rate. A quantile analysis is performed on the uncontrolled hydrogen release: practical values of the energy-to-power ratios for LOHC systems are 2–6 h. A normalised release time is introduced to assess the efficiency of the control system. Temperature control leads to the best results, with an efficiency higher than 90% for the entire load range, while pressure control leads to satisfactory performance only at low loads. The mass flow rate control is the least effective, with efficiencies always below 80%. Sensitivity analysis highlights the temperature control strategy as the best fit to enhance controllability across the whole power range. Pressure control presents a more variable trend. • Liquid Organic Hydrogen Carriers release hydrogen at highly variable flow rates • Flow rate control systems are required to meet end-user demand • Control variables: discharge pressure, thermal fluid inlet temperature and flow rate • Heat transfer fluid inlet temperature provides the most effective control • Very good controllability expected with synergic pressure and temperature controls [ABSTRACT FROM AUTHOR]