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This review addresses the diverse applications of multiphase flows, focusing on drilling, completions, and injection activities in the oil and gas industry. Identifying contemporary challenges and suggesting future research directions, it comprehensively reviews evolving applications in these multidisciplinary topics. In drilling, challenges such as gas kicks, cutting transport, and hole cleaning are explored. The application of immersion cooling technology in surface facilities for gas fields utilized in integrated bitcoin mining is also discussed. Nanotechnology, particularly the use of nanoparticles and nanofluids, shows promise in mitigating particulate flow issues and controlling macroscopic fluid behavior. Nanofluids find applications in drilling for formation strengthening and mitigating formation damage in completions as highlighted in this work, as well as in subsurface injection for Enhanced Oil Recovery (EOR), waterflooding, reservoir mapping, and sequestration tracking. The review emphasizes the need for techno-economic analyses using multiphase flow models, particularly in scenarios involving fluid injection for energy storage. Addressing these multiphase flow challenges is crucial for the future of energy diversity and transition initiatives, offering benefits such as financial stability, resilience, sustainability, and reliable supply chains. The first part of this review presents the application of multiphase (typical gas, liquid, solid) flow models and technology for drilling, completion, and injection operations. While the second part reviews the applications of multiphase particulate (nanofluid) flow technology, the use of Computational Fluid Dynamics (CFD), Machine Learning (ML), and system modeling for multiphase flow models in drilling, completions, and injection operations.

This review addresses the diverse applications of multiphase flows, focusing on drilling, completions, and injection activities in the oil and gas industry. Identifying contemporary challenges and suggesting future research directions, it comprehensively reviews evolving applications in these multidisciplinary topics. In drilling, challenges such as gas kicks, cutting transport, and hole cleaning are explored. The application of immersion cooling technology in surface facilities for gas fields utilized in integrated bitcoin mining is also discussed. Nanotechnology, particularly the use of nanoparticles and nanofluids, shows promise in mitigating particulate flow issues and controlling macroscopic fluid behavior. Nanofluids find applications in drilling for formation strengthening and mitigating formation damage in completions as highlighted in this work, as well as in subsurface injection for Enhanced Oil Recovery (EOR), waterflooding, reservoir mapping, and sequestration tracking. The review emphasizes the need for techno-economic analyses using multiphase flow models, particularly in scenarios involving fluid injection for energy storage. Addressing these multiphase flow challenges is crucial for the future of energy diversity and transition initiatives, offering benefits such as financial stability, resilience, sustainability, and reliable supply chains. In the first part of this review, we presented the application of multiphase (typical gas, liquid, solid) flow models and technology for drilling, completion, and injection operations. This second part of this review presents the applications of multiphase particulate (nanofluid) flow technology for drilling, completion, and injection operations. It aims to identify technology development needs related to multiphase flows, enhancing research endeavors for better cognition and mitigation of the identified issues. The use of Computational Fluid Dynamics (CFD), Machine Learning (ML), and system modeling for multiphase flow models is also discussed.

pH-responsive polymers are attracting much interest from researchers because of their wide application potentials in areas like biosensor, bioseparator, bioreactor, biocatalysis, drug delivery, and water treatments. In this investigation a two-step process is evaluated to prepare carboxyl(–COOH) functional submicrometer-sized pH-responsive composite polymer particles. First, submicrometer-sized polystyrene (PS) particles are prepared by a modified conventional dispersion polymerization. In the second step, PS/poly(methacrylic acid-acrylamide-ethylene glycol dimethacrylate) [PS/P(MAA-AAm-EGDMA)] composite polymer particles are synthesized by seeded co-polymerization of methacrylic acid, acrylamide, and ethylene glycol dimethacrylate in the presence of PS seed particles. The size distributions and morphologies analyzed by electron micrographs suggested that seeded copolymerization smoothly occurred without formation of any secondary tiny copolymer particles. The surface composition and functionality are confirmed by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance. The hydrodynamic diameter increased with the increase in pH values as part of the carboxyl groups are deprotonated, which favored the swelling of copolymer layer formed around the surface of PS particles. The adsorption of cationic and anionic surfactants at two different pH values showed that adsorption of cationic surfactant is favored at higher pH value whereas that of anionic surfactant is favored at lower pH value.

This paper presents the design and construction of a fixed bed batch pyrolysis reactor. The reactor is further used for the production of pyro oil from scrap tire. The result shows that reactor yields a maximum pyro oil of 42 wt% at the temperature of 400 °C with a feed size of 15 cm3. The produced pyro oil has a higher viscosity of 4.5 cSt and heating value of 42.5 MJ/kg. Thus pyro oil cannot be used directly in engine operation but as a furnace oil or fuel in boiler operation. The char is potential for using as a fertilizer, production of conveyor belt and footwear.

•Successful fabrication of Al/ZnO:Al heterojunctionby low cost spray pyrolysis technique.•Rectifying characteristicsof Al/ZnO:Al heterojunction.•Ideality factors of Al/ZnO:Al junction are found varying from 2.56 to 5.45 for different doping concentration of Al.•Built in potential varies from 2.43 V to 2.74 V for different doping concentration of Al.

Biodiesel from green energy source is gaining tremendous attention for ecofriendly and economically aspect. In this investigation, a two-step process was developed for the production of biodiesel from microalgae Spirulina maximaand determined best operating conditions for the steps. In the first stage, acid esterification was conducted to lessen acid value (AV) from 10.66 to 0.51 mgKOH/g of the feedstock and optimal conditions for maximum esterified oil yielding were found at molar ratio 12:1, temperature 60°C, 1% (wt%) H2SO4, and mixing intensity 400 rpm for a reaction time of 90 min. The second stage alkali transesterification was carried out for maximum biodiesel yielding (86.1%) and optimal conditions were found at molar ratio 9:1, temperature 65°C, mixing intensity 600 rpm, catalyst concentration 0.75% (wt%) KOH for a reaction time of 20 min. Biodiesel were analyzed according to ASTM standards and results were within standards limit. Results will helpful to produce third generation algal biodiesel from microalgae Spirulina maximain an efficient manner.

Due to the great effect of defects on the properties of the material including strength, ductility, resistivity and opacity, there are many techniques that are used in defect detecting. Positron annihilation spectroscopy (PAS), Vickers hardness, and X-ray diffraction were used to study the influence of plastic deformation on the properties of 8006 Al-alloy in this work. An increase in the positron lifetime and Vickers hardness with a bit Broadening of XRD peaks was observed with increasing the degree of deformation reflecting a large dislocation density produced by plastic deformation.

The continuous advancement in the field of imaging sensor necessitates the development of an efficient image fusion technique. The multi-focal image fusion extracts the in-focus information from the source images to construct a single composite image with increased depth-of-field. Traditionally, the information in multi-focal images is divided into two categories: in-focus and out-of-focus data. Instead of using a binary focus map, in this work we calculate the degree of focus for each source image using fuzzy logic. The fused image is then generated based on the weighted sum of this information. An initial focus tri-state map is built for each input image by using spatial frequency and a proposed focus measure named as alternate sum modified Laplacian. For the cases where these measures indicate different source images to contain focused pixel or have equal strength, another focus measure based on sum of gradient is employed to calculate the degree of focus in a fuzzy inference system. Finally, the fused image is computed from the weights determined by the degree of focus map of each image. The proposed algorithm is designed to fuse two source images, whereas fusion of multiple input images can be performed by fusing a source image with the fusion output of the previous input group. The comparison of the proposed method with several transform and pixel domain based techniques are conducted in terms of both subjective visual assessment and objective quantitative evaluation. Experimental results demonstrate that our method can be competitive with or even outperforms the methods in comparison. [ABSTRACT FROM AUTHOR]

SummaryThe study was aimed to identify, characterize and describe the phenotypic variation of indigenous goose populations in Bangladesh. The research was conducted at Sylhet Sadar Upazilla in Sylhet district and encompassed about 141 geese (74 brown type and 67 white type). Least Square Mean ± SE of body length, wing span, shank length, beak length and head length of mature indigenous goose were 73.47 ± 0.95, 134.53 ± 1.38, 9.27 ± 0.09, 8.88 ± 0.10 and 6.42 ± 0.02 cm, respectively. Males were significantly (p< 0.01) higher than their female counterparts for all morphometric traits but no significant differences (p> 0.05) were found between two types. The body weight of indigenous goose at day old, 2-week, 1-month, 2-month and 10-month of age were 95.45 ± 0.88, 148.59 ± 1.55, 407.34 ± 7.27 gm, 1.19 ± 0.03 kg and 3.65 ± 0.06 kg, respectively. Males were significantly (p< 0.01) heavier than females in all age groups except day old gosling but no significant difference (p> 0.05) were observed for body weights between two types of goose. Egg weight, egg length, egg width, incubation period, clutch size, number of eggs in a breeding season and age at first egg were 131.85 ± 1.70 gm, 7.40 ± 0.02 cm, 5.22 ± 0.02 cm, 30.30 ± 0.07 days, 7.42 ± 0.08, 20.52 ± 0.38 and 313.22 ± 3.03 days, respectively. The number of eggs in a breeding season of brown type were significantly (p< 0.05) higher than that of white type goose. This study provides a bench mark for the morphometric traits and performance of goose in Bangladesh.

Nowadays, epoxidized vegetable oils are of major significance since they are derived from renewable and sustainable natural resources and are eco-friendly. Epoxide is a crucial chemical precursor to produce alcohols, glycols, and polymers such as polyester and epoxy resin. Oleic acid’s long alkyl chain including an unsaturated double bond (C=C) makes it an appealing fatty acid for producing eco-friendly epoxide. The epoxidation of unsaturated fatty acid was accomplished by generating performic acid in situ to yield epoxidized oleic acid. The result of this reaction will be dihydroxystearic acid (DHSA). DHSA is one of the chemical precursors used to manufacture cosmetics. The optimal level of epoxidized unsaturated oleic acid was 82%.

The searching of environmentally friendly materials that have potential to replacement mineral oil is currently being considered a top priority research topic in the fuel and energy sector. This paper presents the influence of ultrasound-assisted transesterification of jatropha oil to isopropyl ester and the optimum condition. The transesterification was performed by using isopropyl alcohol as solvent in the presence of ultrasound operating frequency constant at 35 kHz. The isopropyl ester content of product was 97.80 % under the the reaction temperature of 60 °C, isopropyl alcohol to jatropha oil molar ratio of 8 : 1 within the reaction time of 15 minutes.

Dimensional accuracy plays important criteria in producing high quality machined parts. This is a big challenge to manufacturers of precision components to produce good quality parts with minimum manufacturing error. The focus of this paper is to study the influence of the machine tool rigidity and cutting parameters on dimensional accuracy in turning operation. A method was prepared for identifying the factors effecting dimensional accuracy in a turning process. Experimental setup involved computerized numerical control (CNC) lathe machine, with VBMT 160404 carbide insert and mild steel, as cutting tool and workpiece respectively. The statistical analysis was used for analyzing and determining the accuracy of experimental data through Minitab statistical software. The regressions model was developed. The developed regression model could be used to predict the dimensional precision of the parts based on machine tool vibration and machining parameters during turning process. This is the aspect to be seriously considered and be applied in attaining sustainable machine tool development during design and development stage and its usage. This finding provides useful guidelines for manufacturers to produce high quality machined parts at minimum manufacturing cost. It was found that the cutting speed, feed rate, final part length, vibration x and vibration z have significant effects on dimensional accuracy of the machined parts.

•Configuration, and process variables of the solar pyrolysis process are reviewed.•Parabolic dish and trough are two popular concentrators in solar pyrolysis.•A fixed bed batch type reactor is common in reactor- concentrator combination.•Temperature is the major dominant parameter in the yields.•A critical discussion, some challenges, and their probable solutions are discussed.

Improving methanol resistance and dimensional stability are the main challenges in polymer electrolyte membranes for direct methanol fuel cell application. In this study, nanocrystalline cellulose (NCC) was initially synthesized and then blended together with poly (vinylidene fluoride) (NCC/PVDF) and the resultant dope solution was used for the fabrication of membranes via solution casting method. The physical characteristics of the membranes were evaluated using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). Crystallinity differences between all the membranes were confirmed by x-ray diffraction (XRD). Results revealed that the swelling ratio at 80° C and methanol permeability of NCC-3/PVDF were as low as 15.19% and 2.69 × 10−9cm2/s, respectively compared to Nafion 117 (18.25% and 2.74 ×10−6cm2/s). It was found that blending hydrophilic NCC with hydrophobic PVDF could profoundly influence the physical properties of the membrane. High crystallinity structure of NCC/PVDF membrane significantly improved the dimensional stability and reduce methanol permeation rate. Although the proton conductivity of NCC-3/PVDF (7.57 ×10−2mS cm−1) is low, its selectivity (28.141 ×103 Scm−3s) was higher than that of Nafion 117 (0.074 ×103Scm−3s) due to improvements in methanol barrier. The alternative membrane prepared from NCC and PVDF successfully overcame the weaknesses of Nafion 117, hence exhibiting its potential for DMFC application.

A facile, rapid, green, and novel clean synthesis of advanced RGO/bimetallic Pt-Pd alloy/CeO2nanocomposite electrocatalyst with the enhanced electrocatalytic performance of methanol oxidation reaction (MOR) has been successfully carried out through a one-step hydrothermal-assisted formic acid reduction reaction without applying any template or surfactant. The as-prepared electrocatalysts were extensively characterized by X-ray Powder Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive X-ray Spectroscopy (EDX), High-Resolution Transmission Electron Microscopy (HRTEM), and Field-Emission Scanning Electron Microscopy (FESEM) to confirm the formation, deposition and homogenous distribution of Pt-Pd alloy and CeO2nanoparticles (NPs) on the surface of RGO. Meanwhile, the electrocatalytic activity and the long-term stability performance of the as-prepared electrocatalysts towards MOR were employed by cyclic voltammogram and chronoamperometry, respectively. Noticeably, the as-prepared RGO/bimetallic Pt-Pd alloy/CeO2nanocomposite electrocatalyst presented very outstanding electrocatalytic performance with higher maximum forward peak current density (69.82 mA cm−2) than those of RGO/monometallic Pt/CeO2(23.81 mA cm−2) and RGO/monometallic Pd/CeO2(1.39 mA cm−2) toward MOR in acidic medium denoting to the large surface area and excellent conductivity of RGO, homogenous distribution of Pt-Pd alloy electrocatalyst as well as a synergistic effect between Pt-Pd alloy NPs, RGO, and CeO2NPs. Moreover, the RGO/bimetallic Pt-Pd alloy/CeO2electrocatalyst also possesses excellent stability and exceptional poisoning tolerance through the advantages of utilizing Pt-Pd alloy NPs and the synergistic effect of CeO2NPs. Therefore, this study may open a new facile route with the convenient experimental procedure, clean, reasonable cost, easy to handle, no time consuming, and easy to scale-up for the large quantity production of an advanced anode electrocatalyst for direct methanol fuel cell application.

Sulfonated poly (ether ether ketone) (SPEEK) at higher degrees of sulfonation (DS) produced high proton conductivity, but it is impractical for DMFC application due to excessive swelling and severe methanol crossover. In this study, a novel blended membrane based on SPEEK at higher degrees of sulfonation (DS) of 80% and epoxidized natural rubber (ENR-50) are prepared at different mass ratio of SPEEK to ENR-50 (9.5:0.5, 9.0:1.0, 8.5:1.5, 8.0:2.0, and 7.5:2.5) via solution intercalation method. The influence of ENR-50 loading on the physical properties of SPEEK blends membranes was investigated and compared with the pristine SPEEK and Nafion117 membranes. The blended membranes were characterized by FTIR, which showed a successful chemical interaction between ENR-50 and SPEEK matrix. SEM images revealed a uniform dispersion of ENR-50 droplets in the polymer structure. The water uptake and methanol permeability of SPE50 membrane were found to be decreased with increasing of ENR-50 content. The highest proton conductivity of SPE50 membrane obtained was 47% higher than pure SPEEK, whereas the lowest permeability value obtained was 21 times lower than Nafion117 membrane. Consequently, incorporation of ENR-50 into SPEEK matrix has substantially enhanced the selectivity of the membrane by five folds. Apparently, this newly developed SPE blend membrane can be listed as one of the potential proton electrolyte membranes for the usage in DMFCs.

Traumatic abdominal wall hernia (TAWH) is uncommon in children and most cases are related to handle bar injury. We report a case of TAWH and pelvic fracture following road traffic accident at an unusual site. Part of the transverse colon, along with its mesocolon, was herniated into a defect in the wall of left lower chest and of left upper quadrant of abdomen. Laparotomy was done and the hernial defect was repaired.

ABSTRACTHuman cytomegalovirus (HCMV) antigens in glioblastoma (GBM) present opportunities for personalised immunotherapy. However, their presence in GBM tissue is still under debate, and evidence of their impact on functional immune responses and prognosis is sparse. Here, we investigated the presence of pp65 (UL83) and immediate early 1 (IE-1) HCMV antigens in a cohort of Norwegian GBM patients (n= 177), using qPCR, immunohistochemistry, and serology. HCMV status was then used to investigate whether viral antigens influenced immune cell phenotype, infiltration, activation and patient survival. Pp65 and IE-1 were detected by qPCR in 23% and 43% of GBM patients, respectively. Furthermore, there was increased seropositivity in GBM patients relative to donors (79% vs. 48%, respectively; Logistic regression, OR = 4.05, 95%CI [1.807-9.114], P= 0.001, also when adjusted for age (OR = 2.84, 95%CI [1.110-7.275], P= 0.029). Tissue IE-1-positivity correlated with increased CD3+CD8+T-cell infiltration (P< 0.0001), where CD8+effector memory T (TEM) cells accounted for the majority of CD8+T cells compared with peripheral blood of HCMV+patients (P< 0.0001), and HCMV+(P< 0.001) and HCMV−(P< 0.001) donors. HLA-A2/B8-restricted HCMV-specific CD8+T cells were more frequent in blood and tumor of HCMV+GBM patients compared with seronegative patients, and donors irrespective of their serostatus. In biopsies, the HCMV-specific CD8+TEMcells highly expressed CTLA-4 and PD-1 immune checkpoint protein markers compared with populations in peripheral blood (P< 0.001 and P< 0.0001), which expressed 3-fold greater levels of CD28 (P< 0.001 and P< 0.0001). These peripheral blood T cells correspondingly secreted higher levels of IFNγ in response to pp65 and IE-1 peptide stimulation (P< 0.001). Thus, despite apparent increased immunogenicity of HCMV compared with tumor antigens, the T cells were tolerised, and HCMV status did not impact patient survival (Log Rank3.53HR = 0.85 95%CI [0.564-1.290], P =0.45). Enhancing immune functionality in the tumor microenvironment thus may improve patient outcome.