Volume Ratio Research Articles

Synthesis of PPy-MnO2 Nanocomposite for Utilization in Supercapacitor Applications

Polypyrrole (PPy) nanocomposites were prepared using chemical oxidation and were combined with manganese oxide (MnO2) nanoparticles. The PPY-MnO2 nanocomposite was synthesized by integrating PPy nanofibers with varying volume ratio percentages of MnO2 dopant (10, 30, and 50% vol. ratio). The structural features of the PPy and PPy-MnO2 nanocomposite were investigated using X-ray diffraction (XRD). Fourier transfor infrared (FTIR) spectroscopy was used to demonstrate the molecular structures of primary materials and the final product of PPy, MnO2, and PPy- MnO2 nanocomposites. Field Emission Scanning Electron Microscopy (FESEM) showed that the morphology of PPy consisted of a network of nanofibers. Increasing the volume ratios of manganese oxide added to the PPY nanofiber led to the increase of manganese oxide nanoparticles on the surface of the PPY nanofiber network. This resulted in a noticeable alteration in the structure of the nanocomposite. It has been observed that the nanocomposites demonstrate a significant level of pseudocapacitive activity. The highest capacitance of 236 F/g was observed when pure PPy was doped with 30% MnO2 compared to 125 F/g of the pure PPy.

Association of Preserved Ratio Impaired Spirometry with Arterial Stiffness.

Rationale: Preserved ratio impaired spirometry (PRISm) is a recently recognized spirometric pattern defined by a ratio of forced expiratory volume in 1 second to forced vital capacity of at least 0.70 and a forced expiratory volume in 1 second <80% of reference. For unclear reasons, PRISm is associated with increased cardiovascular (CV) morbidity and mortality. Arterial stiffness is a major mechanism of CV disease, which can be measured by carotid-femoral pulse-wave velocity (cfPWV). Objectives: We explored the hypothesis that cfPWV would be increased in individuals with PRISm and airflow limitation (AL). Methods: We measured forced spirometry, lung volumes by body plethysmography, and cfPWV in 9,466 subjects recruited from the general population in the Austrian cross-sectional LEAD (Lung, Heart, Social, Body) study and tested the association of arterial stiffness with PRISm and AL by multivariable linear regression analysis. Individuals younger than 18 years were excluded from the study. Results: Individuals with PRISm (n = 431; 4.6%) were of similar age to those with normal spirometry (n = 8,136; 85.9%) and significantly younger than those with AL (n = 899; 9.5%). Arterial hypertension, diabetes mellitus, coronary artery disease, heart failure, and peripheral arterial occlusive disease were significantly more common in individuals with PRISm than in those with normal lung function and similar to those with AL. There was a significant association between PRISm and arterial stiffness on bivariate linear regression analysis (crude model, β = 0.038; 95% confidence interval [CI], 0.016-0.058), which persisted after robust adjustment for clinical confounders upon multivariable analysis (final model, β = 0.017; 95% CI, 0.001-0.032). cfPWV was significantly higher in individuals with PRISm irrespective of the presence of established CV disease or pulmonary restriction. AL also showed a significant association with arterial stiffness on multivariable linear regression analysis (final model, β = 0.025; 95% CI, 0.009-0.042). Conclusions: Arterial stiffness measured by cfPWV is increased in individuals with PRISm independent of CV disease and risk factors. The pathobiological mechanisms underlying this association deserve further research.

Comprehensive Evaluation of Fetal Renal Ultrasound Parameters for Fetal Growth Restriction

ObjectiveThis study aims to investigate variances in renal ultrasound parameters between fetuses experiencing fetal growth restriction (FGR) and those with normal intrauterine development, with the intent to offer actionable insights for clinical management. MethodForty-five pregnant women diagnosed with FGR between 28 to 36 weeks of gestation, who underwent examination at Wenzhou People's Hospital from September 2021 to June 2023, constituted the FGR group. Concurrently, 65 pregnant women with normal intrauterine development at matching gestational weeks formed the control group. Renal ultrasound parameters, encompassing renal artery peak systolic velocity (PSV), end diastolic velocity (EDV), time averaged maximum velocity (TAMX), resistive indices (S/D, PI, RI), ratios of renal volume to gestational age (RV/WEEK) and estimated fetal weight (RV/EFW), vascular indices (VI, FI, VFI), were compared between the two groups. All parameters represented the mean values of bilateral kidneys. ResultIn the FGR group, fetal renal artery PSV (37.71 ± 9.93 cm/s), EDV (6.19 ± 1.50 cm/s), TAMX (15.10 ± 3.83 cm/s), RV/WEEK (0.45 ± 0.12), RV/EFW (7.53 ± 3.24), VI (22.19 ± 15.00), and VFI (5.53 ± 3.63) were significantly lower compared to the control group (PSV: 47.11 ± 11.24 cm/s, EDV: 7.13 ± 2.00 cm/s, TAMX: 17.85 ± 3.85 cm/s, RV/WEEK: 0.66 ± 0.19, RV/EFW:9.20 ± 3.17, VI: 28.67 ± 14.72, VFI: 7.40 ± 3.68). Conversely, fetal renal artery resistive indices (S/D: 9.09 ± 2.58, PI: 2.71 ± 0.56, RI: 0.92 ± 0.04) in the FGR group were notably higher than those in the control group (S/D: 6.22 ± 1.93, PI: 2.20 ± 0.73, RI: 0.87 ± 0.04), with statistical significance (P<0.05). No significant difference was found in renal FI between the FGR group (26.78 ± 6.59) and the control group (26.89 ± 5.82) (P>0.05). Receiver operating characteristic (ROC) curve analysis revealed higher diagnostic efficacy for RV/WEEK and RI among individual indicators, while combined parameter application yielded the highest diagnostic efficiency. ConclusionUtilizing a comprehensive evaluation of fetal kidney ultrasound parameters with multiple indices facilitates early screening and diagnosis of FGR fetuses, thereby aiding clinical decision-making and enhancing newborn birth outcomes.

Can serum tumor marker densities according to tumor volume and testicle size be used to predict progression in patients with testicular cancer?

The objective of this study is to determine the role of tumor marker density (TMD) values such as alpha-fetoprotein tumor volume ratio (ATVR), beta-human chorionic gonadotropin tumor volume ratio (βTVR), alpha-fetoprotein testicle size ratio (ATSR), beta-human chorionic gonadotropin testicle size ratio (βTSR), lactate dehydrogenase tumor volume ratio (LTVR), and lactate dehydrogenase testicle size ratio (LTSR) in the determination of progression-free survival (PFS) in patients with testicular cancer. A retrospective study was conducted of 95 patients followed-up in our clinic with a diagnosis of testicular cancer between January 2015 and August 2022. Patients were grouped according to clinical stage, as either early stage (n = 50) or advanced stage (n = 45). Clinical and pathological data and TMD values for all patients were recorded. The median age of patients was 35 years (21-63 years). All TMDs except LTVR in advanced stage patients were found to be significantly higher than those of early stage patients (p < 0.05). Median ATVR (2.58 vs. 0.0), ATSR (0.63 vs. 0.03), βTVR (0.9 vs. 0.009), and βTSR (0.18 vs. 0.007) of the nonseminoma patients were found to be significantly higher than those of the seminoma patients, respectively (p < 0.001). Progression-free survival (months) was decreased in seminoma patients with high values of βTVR (11.3 ± 1.9 vs. 35.2 ± 0.7), βTSR (16.2 ± 3.4 vs. 35.2 ± 0.75), LTVR (17.7 ± 3.4 vs. 35.2 ± 0.7), and LTSR (21.5 ± 3.13 vs. 35.09 ± 0.8) (p < 0.001). Decreased PFS (months) was associated with higher values of ATVR (5.37 ± 0.7 vs. 35.05 ± 0.93), βTVR (7.4 ± 1.5 vs. 34.6 ± 1.3), ATSR (5.37 ± 0.75 vs. 35.05 ± 0.9), βTSR (7 ± 1.5 vs. 34.6 ± 1.3), and LTSR (7.9 ± 1.2 vs. 34.3 ± 1.5) in nonseminoma patients (p < 0.001). Based on multivariate analysis, βTVR-LTVR and ATVR-ATSR were determined to be independent risk factors for reduced PFS in seminoma and nonseminoma patients, respectively (p < 0.05). The results of this study suggest that the calculation of TMDs could be a promising and simple method for prediction of PFS among testicular cancer patients.

Characterization, Antibacterial and Antioxidant of Phytosynthesized Zinc Oxide Nanoparticles Using Aloe Fleurentinorum Leaves Extract

The environmentally friendly methods for synthesizing metal oxide nanoparticles effectively save time, money, and effort. These methods involve the phytosynthesis process, which depends on plant extracts. To produce zinc oxide nanoparticles (ZnO − NPs), we used at this work an extract of Aloe Fleurentinorum Leaves (AFL) as a reducing, capping, and stabilizing agent. As well as the effect of altering some parameters on the synthesis of ZnO − NPs, such as the Temperature (T), the potential of hydrogen (pH), and the volume ratio (V/V), was studied using an X-ray diffractometer (XRD), crystallite size, and microstrain was determined, and the average crystallite size was between 16.50, and 25.99 nm. Also, ZnO − NPs were characterized optically by a UV-Vis spectrophotometer and got 3.13 eV band gap energy. Fourier transfer infrared spectroscopy was used for characterization. The antibacterial activities of ZnO − NPs were investigated against four bacterial species, and the results exhibit a noticeable effect, especially against gram-positive species, with inhibition zones ranging from 17 to 20 mm for the different concentrations. Also, the DPPH free radical method was used to evaluate the antioxidant properties of the synthesized zinc oxide nanoparticles at various concentrations, which showed a moderate scavenging efficiency of 52.74% at 800 µg/mL.

Enhanced removal of antibiotic-resistant genes by sodium persulfate catalyzed by nanoscale zero-valent iron modified by Ginkgo biloba L. leaf

ABSTRACT In this study, nanoscale zero-valent iron (nZVI) modified by Ginkgo biloba L. leaf (G-nZVI), as an effective catalyst, exhibited excellent activation of sodium persulfate (PS), which could achieve higher removal efficiency of antibiotic-resistant genes (ARGs) in the Fen River than PS + nZVI system. This study utilizes forestry waste to address the limitations of using Fe2+/nZVI as an activator for the removal of ARGs. This approach adheres to the principle of employing waste to treat waste. The technology converts G. biloba L. leaf into plant extracts that are rich in a variety of bioactive components, rather than purifying natural biomolecules, which decreases operational complexity. In addition, the G-nZVI + PS system demonstrates superior removal performance to single components in the system. Consequently, the mechanism underlying the G-nZVI + PS treatment is attributed to peroxidation induced by radicals. In this context, the results of ARG removal by G-nZVI + PS with different G. biloba L. leaf /FeSO4·7H2O volume ratios indicated that the G. biloba L. leaf enhanced the conversion of Fe3+ to Fe2+, thereby generating more radicals through electron transfer between the biomass and G-nZVI. This research underscores the advantages of modifying G. biloba L. leaf for improved catalytic efficiency and the role of the components within the system.

Association of Prenatal Congenital Lung Malformation Volume Ratio to Postnatal Computed Tomography Characteristics

IntroductionCongenital lung malformations (CLMs) are diverse and readily diagnosed on prenatal ultrasound. Postnatal computed tomography (CT) characteristics, including volume, are used in centers for the clinical decision-making of asymptomatic CLM. We aim to evaluate the relationship of prenatal CLM-volume ratio (CVR) to postnatal CT characteristics by suspected prenatal diagnosis and postnatal radiological diagnosis. MethodsWe performed a single-center retrospective review of all patients evaluated with prenatally diagnosed CLM (May 2015-December 2022). Demographics, prenatal imaging findings at initial evaluation, and postnatal radiological diagnosis/imaging findings were analyzed with descriptive statistics. Pairwise correlation coefficient tests were performed to analyze the correlation between prenatal CVR and postnatal CT lesion size stratified by diagnosis. ResultsOf 123 patients referred and evaluated, suspected prenatal diagnoses consisted of 68 bronchial atresia (BA), 20 intralobar bronchopulmonary sequestration (iBPS), 20 extralobar bronchopulmonary sequestration (eBPS), and nine congenital pulmonary airway malformation (CPAM). Postnatal radiological diagnoses consisted of 53 BA, 22 iBPS, 14 eBPS, and 20 CPAM. Overall correlation coefficient of prenatal CVR to postnatal CT lesion size volume was 0.56. By suspected prenatal diagnosis, correlation coefficients were 0.61 (BA), 0.59 (iBPS), 0.29 (eBPS), and 0.51 (CPAM). For postnatal radiological diagnosis, correlation coefficients were 0.58 (BA), 0.56 (iBPS), 0.33 (eBPS), and 0.62 (CPAM). ConclusionsOur results indicate that initial CVR is overall consistent with the postnatal CT lesion size. This correlation is present in suspected prenatal diagnoses of BA and iBPS and postnatal radiological diagnoses of BA, iBPS, and CPAM. Additional studies analyzing long-term follow-up should be conducted to specify the safety of patients who undergo observation rather than surgical intervention.

Nanosized-laser-induced sub-20 nm homogenous alloy nanoparticles

Alloy nanoparticles (NPs) have great potential in nanosized 3D-printing, surface coating, plasmonic enhancement, information coding, and so forth. However, chemical-pollution-free and homogeneous sub-20 nm NPs maintain still a challenge in preparation. Here we present a smart nanosecond laser scan strategy of alloy-NPs preparation on a bilayer metal film by using a nanosized focused beam, successfully realizing controllable fabrication of the sub-20 nm homogeneous alloy NPs without pollution. As a demonstration, various sub-20 nm AgCu NPs with different volume ratios have been prepared, all NPs show narrow size distribution and uniform interparticle spacing. This simple and cost-effective method is stable and adaptable for other alloy-NPs such as AuAg NPs. In addition, such alloy NPs exhibit two-peak plasma resonance feature and information coding capacity. We believe that homogenous alloy sub-20 nm NPs will provide new application opportunities in many fields.

The Role of FEV1/FVC in the Prediction of Acute Exacerbation of COPD.

Whether the ratio of forced expiratory volume in 1 second to forced vital capacity (FEV1/FVC) can be used as a biomarker to predict the risk of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is unclear. To investigate the predictive role of FEV1/FVC for AECOPD, we analyzed data from an observational and multicenter cohort study of 2,043 patients with COPD in KOREA. Exposures were post-bronchodilator FEV1/FVC and/or percentage predicted FEV1 (FEV1%pred). The outcome was the development of AECOPD during the first year of follow-up. During the first year of follow-up, the proportion of patients who developed AECOPD increased as FEV1/FVC decreased (P<0.01). FEV1/FVC and FEV1%pred had similar predictive power for AECOPD, with optimal predictive cut-offs of approximately 0.5 for FEV1/FVC and 50% for FEV1%pred. When the participants were classified into groups based on these cut-offs, compared with a high both-lung function group (FEV1/FVC≥0.5 and FEV1%pred≥50%), the low-FEV1 group (FEV1/FVC≥0.5 and FEV1%pred<50) had a modestly increased risk of severe AECOPD (adjusted odds ratio[aOR]=3.12; 95% confidence interval[CI]=1.59-6.16), while the risk of severe AECOPD was the highest in the low both-lung function group (FEV1%pred<50% and FEV1/FVC<0.5) (aOR=5.16; 95% CI=3.34-7.97). FEV1/FVC is a spirometric biomarker predictive of AECOPD. In countries where FEV1%pred is not available for their population, FEV1/FVC could be used as a biomarker for assessing the risk of AECOPD. In countries where accurate FEV1%pred is available, both FEV1%pred and FEV1/FVC could be used to provide additional information to assess the risk of AECOPD.

Generation, control, and application of stable bubbles in a hypersonic acoustic system.

Bubble-based microfluidics has been applied in many fields. However, there remains a need for a facile and flexible method for stable bubble generation and control in a microchannel. This paper reports a hypersonic acoustic system that can generate and release functional stable bubbles in a microchannel in an on-demand manner. It was found that the hypersonic frequency in this system played a vital role in the generation and control of bubbles. Specifically, a nanostructurally enhanced acoustic resonator was used to generate highly localized ultrahigh-frequency acoustic waves that ensured the feasibility and rapidity of bubble generation. Simultaneously, the acoustothermal effect of hypersound was harnessed to effectuate precise control over the bubble size. In addition, high-throughput droplet splitting was performed to confirm the stability of bubbles and their functionality in micromanipulation. The results showed that a mother droplet could be split controllably into a desired number of daughter droplets with specific volume ratios. In summary, the hypersonic acoustic system was demonstrated to be capable of on-demand-generation of stable bubbles in a microfluidic context and thus may extend the bubble-based applications.

Microstructure and mechanical characteristics of Al1050/B2O3+Cu hybrid surface nanocomposite fabricated using friction stir processing

Abstract In the realm of advanced materials engineering, the development of hybrid nanocomposites has garnered significant attention due to their superior mechanical properties and potential applications. The primary aim of this research is to develop a surface hybrid nanocomposite using Al1050 aluminium alloy (5 mm thickness) as the base material through friction stir processing. B2O3 nano-powder, averaging 100 nm in size, and Cu micro-powder, averaging 5 µm in size, were incorporated into the aluminium surface in various volume ratios using the Friction Stir Processing (FSP). The processing parameters included a tool rotational speed of 1250 rpm, a feed rate of 50 mm/min, and a tilt angle of 3°. The number of passes was set at two levels: 1 and 3 passes. The influence of the volume ratio of constituents and the number of passes on the microstructure and mechanical properties of the resulting composite was thoroughly explored. The samples underwent tensile tests, microhardness tests, and metallographic examinations using both Optical Microscopy (OM) and Field Emission Scanning Electron Microscopy (FE-SEM). The composite with 25%-B2O3-75%-Cu composition exhibited the highest stress and hardness values, measuring 141 MPa and 58.14 HV, respectively. The enhanced strength of this sample is attributed to the presence of additives and the resultant grain size.&amp;#xD;

Starch Nanoparticles Based on Ultrasonication Pretreatment and Enzyme Posttreatment: Preparation, Optimization, and Biophysical Characterization

AbstractStarch nanoparticles (SNPs), due to their minimum particle size and maximum surface to volume ratio do not have starch limitations such as low solubility and digestibility. SNPs in colloidal form were enzymatically produced using enzyme of α‐amylase in combination toultrasinication technique to accomplished SNPs gelatinization. Results indicated that SNPs with smallest particle size (109 nm) and polydispersity index (0.560), and highest zeta potential (−32.16 mV) and antioxidant activity (30%) values was obtained using 2.10 mL enzyme and ultrasonication time of 69 s. SNPs in powder form were produced using obtained optimum conditions and a laboratory freeze dryer with chamber temperature and pressure of −70 °C and 100 Pa, for 24 h, and characterized Results indicated that the provided native starch had particle size of ranging 6 to 10 µm with zeta potential value of −4.50 mV, prepared SNPs powder had spherical shape and flat surface with mean particle size, zeta potential and specific surface area values of 105 nm, −26.7 mV and 4.70 m2 g−1, respectively. Furthermore, oil separation time for the emulsions having starch and powder of SNPs, were 43 and 297 s, respectively. While, for the sample without emulsifier (control), this time was 22 s.

Effect of Cu–Al Ratio on Microstructure and Mechanical Properties of Cu–Al Alloys Prepared by Powder Metallurgy

Cu–Al alloys are widely used in electronics, new energy, and other fields due to the combination of th excellent corrosion resistance and electrical conductivity of Cu and the light weight of Al. In this paper, the powder metallurgy and equal-channel angular pressing compound technology was used to fabricate a Cu–Al alloy joint, which can be used to replace armor. Devices such as an optical microscope, electron scanning microscope, and microhardness scale were used to characterize the microstructure and mechanical properties of the Cu–Al alloys. The finite element analysis software Abaqus was used to analyze stress distribution during equal-channel angular pressing. The results indicated that the microstructure and properties of Cu–Al alloys were closely related to the volume ratio of Cu–Al. The microhardness and tensile strength were significantly increased by increasing the volume ratio of Cu–Al. As the volume ratio of Cu–Al varied from 1:2 to 2:1, the ultimate tensile strength of the Cu–Al alloys increased from 79.9 MPa to 164.9 MPa at room temperature and the microhardness increased from 60 HV to 101 HV. However, the elongation of the Cu–Al alloys hardly changed; this was about 4.4%. Crack initiation occurred at the Cu–Al interface and spread along the bonding surface of the Cu–Al alloys during the tensile process.

Green Synthesis of Iron Nanoparticles Using Spinacia oleracea and Their Role in Antioxidant Defence

The green synthesis of iron oxide nanoparticles (Fe2O3) using Spinacia oleracea leaf extract is explored in this study. Iron oxide nanoparticles are noted for their unique properties, such as enhanced chemical reactivity due to their high specific surface area to volume ratios. Unlike traditional physical and chemical methods, green synthesis presents an environmental friendly alternative, leveraging biological processes for nanoparticle production. This method is particularly significant due to its potential applications in various fields, including medicine, where iron nanoparticles demonstrate antibacterial activity. However, limited research exists on their antioxidant properties. In this research, Spinacia oleracea leaf extract is utilized to synthesize iron oxide nanoparticles, followed by characterization using UV-Visible spectroscopy, FTIR, XRD, and SEM techniques. The results underscore the necessity for further investigation into the impact of nanoparticles on biological processes and the long-term effects of high nanoparticle concentrations on ecological stability. Additionally, this study includes an evaluation of antioxidant properties of the nanoparticles to address gaps in current research. Key Words Green synthesis, iron oxide, ecological stability, antioxidant, biological, nanoparticles.

Emulsion liquid membrane technique for optimal separation of Ni (II) and Sm (III) using response surface methodology and Box–Behnken experimental setup

ABSTRACT This study evaluated the reliability of the emulsified liquid membrane (ELM) extraction technique for recovering and separating metals, focusing on Nickel (Ni(II)) and Samarium (Sm(III)), both used in electrochemical devices. Key contributions include determining optimal conditions for creating a stable water-in-oil (W/O) emulsion. The optimal conditions were found to be a 5-minute emulsification time, 4 wt.% Span 80 surfactant concentration, a 1.6 volume ratio of the internal phase to the organic phase, 1 M H2SO4 concentration for the internal phase, a 40/160 volume ratio of the emulsion to the external phase, and kerosene as the diluent. Factors affecting the separation of Ni(II) and Sm(III) included the concentrations of the internal aqueous phase, surfactant, and extractant. Under these conditions, an equimolar mixture of Ni(II) and Sm(III) was extracted within 15 min. The study emphasized the importance of phase volume ratio and surfactant concentration for emulsion stability and extraction efficiency. The response surface method (RSM) and Box–Behnken design were used to optimize influential factors, with a modified quadratic model predicting extraction yields of 83.81% for Sm(III) and 15% for Ni(II). The study demonstrates that effective separation of Ni(II) and Sm(III) ions is achievable using this technique, providing valuable insights into efficient and selective metal ion extraction, contributing to the broader field of metal recovery and recycling technologies.

Fast and accurate modelling of twin-screw compressors: A generalised low-order approach

Twin-screw compressors (TSC) are commonly used in heat pump processes due to their robustness and flexibility. They exhibit two core properties, i.e. the swept volume and the built-in volume ratio (BVR), which heavily influence their capacity limits and off-design efficiency. This work presents a new low-order model (i.e. a polynomial model), which can accurately predict a TSC’s behaviour. The model uses the external pressure ratio and volumetric compressor inlet flow rate to calculate isentropic efficiency and compressor speed. The input parameters are normalised with a reference flow rate (calculated from the swept volume) and the BVR, respectively. This results in a generalised model of low numerical cost, which can be used for explorative studies independent of the specific machine size and BVR. A gain in computational speed by a factor of 375 is achieved compared to a semi-empiric reference model. The model displays very good predictive accuracy when used to predict the performance of machines with similar BVRs, but different sizes. A mean deviation from the manufacturer data of 4.29%, 0.88°C and 1.38% for the shaft power, the outlet temperature and the compressor speed can be observed, respectively. When there is a difference in size and BVR, the prediction accuracy is still reasonable but significantly declines for small and very large pressure ratios. Nevertheless, the proposed new approach extends the state-of-the-art by introducing a low-order model, which combines the advantages of low computational cost, high accuracy, physically correct predictions over a wide operational range and scalability to different machine capacities and BVRs. The validation for different fluids indicates a good general prediction accuracy relatively independent of the used fluid.

Applying a mask R-CNN machine learning algorithm for segmenting electron microscope images of ceramic bronze-casting moulds

Material characteristics of casting moulds are crucial for understanding the evolution and diversification of bronze ritual vessel production in Bronze Age China. During relevant studies, a Back Scattered Electron (BSE) image detector is commonly employed to analyze mould microstructure, effectively revealing the volume ratios and shape features of the clay matrix, silt/sand particles, and voids. It is always challenging to analyze and cross-compare these BSE images quantitatively since they typically contain numerous phases with highly irregular shapes. Traditionally, time consuming manual point counting or multi-step image processing were used to obtain semi-quantitative results. Addressing these challenges, we have proposed a deep learning method called BCM-SegNet, an optimized Mask R-CNN-based algorithm for segmenting BSE images of bronze casting moulds and cores. Using the proposed method, key parameters, such as area, Feret diameter, roundness, and solidity of segmented particles, can be provided based on well segmented results, even for the images with complex background. Experimental outcomes show that the algorithm achieves a segmentation precision of 95% and an accuracy of around 91%, demonstrating its strong generalization capability. This study provides a significant foundation for micro-feature analysis of archaeological ceramic materials, classification of particles, and determination of technological processes in archaeological research.

Characterization of temperature regulating, high-temperature rheological and anti-aging properties of asphalt mastic modified with SSPCMs

The objective of this study is to explore the potential of utilizing self-developed SSPCMs as additives for heat storage temperature regulation in asphalt mastic modification. To achieve this aim, a variety of asphalt mastics with different F-A volume ratios and SSPCM contents were formulated, and their high-temperature rheological properties, modification mechanisms, thermoregulation capabilities, and aging resistance performances were analyzed. The results of temperature regulation test indicated that the maximum cooling amplitude of asphalt mastic could reach 11.3°C, showing a great promising application for cooling asphalt pavements. Additionally, the incorporation of SSPCMs generally resulted in positive impacts on both the high-temperature rheological properties and temperature sensitivity of the asphalt mastics. Moreover, the aging indices GAI, ICO and ISO of the modified asphalt mastic with 30 % SSPCMs decreased by 5.6 %, 18.3 % and 8.7 %, respectively, compared with control asphalt mastic, implying that the incorporation of SSPCMs can retard the aging process of asphalt and enhance the thermal oxidative aging resistance of the asphalt mastics. In summary, the current study demonstrates the feasibility, improved performance, and effective thermoregulation properties of SSPCMs in asphalt mastics.

Preparation of cellulose-based porous carbon fibers and their methylene chloride adsorption/desorption behaviors

Methylene chloride is a type of volatile organic compounds for which effective and economical treatment and recovery technologies need to be developed because it is impossible to reburn. In this study, a cellulose-based porous carbon fibers were prepared for the adsorption/desorption of methylene chloride. From the results, the specific surface area and total pore volume of cellulose-based porous carbon fibers were determined to be 1700–2220 m2/g and 0.69–1.03 cm3/g, respectively, and the micropore ratio was observed to be high. As the activation time increased, methylene chloride activity and methylene chloride retentivity increased from 51.75 % to 58.07 % and from 9.08 % to 14.92 %, respectively. Methylene chloride adsorption/desorption showed a high correlation with pore volume, Especially, methylene chloride retentivity had a linear relationship between the mesopore volume and mesopore ratio.

Carbon dioxide stripping from acidic wastewater through a vortex venturi tubular microbubble generator

Microbubble generation technology can improve CO2 stripping efficiency while consuming less sweeping gas. In this paper, a vortex venturi tubular microbubble generator is developed based on the concept of “Initial bubble generation with a thin plate type static mixing element” and “Bubble collapse with a venturi channel”. Microbubble characteristics were tested, followed by post-processing of the focused beam reflectance measurement (FBRM) to obtain a multidimensional dataset. The test results indicated that the microbubble quality generated by the vortex venturi tubular microbubble generator was higher than that of the SV-type static mixer. When the gas-liquid volume ratio was 1, the average bubble diameter was 107.05 μm, and microbubbles accounted for 93.29 %. The average bubble diameter of the SV-type static mixer was 473.55 μm, and the proportion of microbubbles was 23.81 % under identical conditions. Furthermore, the CO2 removal efficiency and pH enhancement rate were greatly affected by the gas-liquid volume ratio and the inlet water flow rate, and both fitted an exponential equation correlation. Accordingly, when the gas-liquid volume ratio increased, the quantity of bubbles generated significantly influenced the CO2 stripping efficiency. The stripping efficiency based on the tubular microbubble generator is significantly higher than that of the SV-type static mixer. When the gas-liquid volume ratio was 1, the CO2 removal efficiency was equivalent to that of the SV-type static mixer at a gas-liquid volume ratio of 3.5. When achieving equal CO2 removal efficiency, the gaseous nitrogen consumption of the tubular microbubble generator was 48.61 %-63.30 % lower than that of the SV-type static mixer, and the corresponding energy consumption of the gas compressor was reduced by 38.24 %-55.83 %. The CO2 stripping process based on the vortex venturi tubular microbubble generator offers an environmentally and economically viable treatment option for acid wastewater.