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Objective To explore a more stable and efficient gene carrier tool by preparing cationic lipid nanobubbles as ultrasound contrast agents and to compare the preparation effects of homemade cationic lipid nanobubbles with those of ordinary lipid microbubbles. Methods Cationic lipid nanobubbles were prepared using distearoylphosphatidylcholine (DSPC) / distearoylphosphatidylethanolamine-polyethylene glycol (DSPEPEG2000) / DC-cholesterol (DC-Chol) at a molar ratio of 9 0.5 1. Simple microbubbles, namely, core nanobubbles, were used as controls. The general physicochemical properties and stability of the nanobubbles in each group were measured, including particle size, surface potential, polydispersity index (PDI), etc. The morphology of the nanobubbles in each group was observed using an inverted microscope and an electron microscope, and their contrast effects in vitro were observed using an agarose gel model. Results The prepared cationic lipid nanobubbles had an average particle size of (564.35±25.93) nm, an average surface charge of (17.6±2.1) mV, a PDI of 0.30±0.16, and a concentration of (4.27±0.31)×108. The core nanobubbles had an average particle size of (582.55±16.30) nm, an average surface charge of (-7.9±1.6) mV, a PDI of 0. 37 ±0.15, and a concentration of (4.24±0.30)×108. There was a statistically significant difference in surface charge between the two groups (P<0.05). Both groups maintained good stability within 2 hours of continuous measurement and showed good contrast effects in vitro. Conclusion The homemade cationic lipid nanobubbles have high positive charges while maintaining good stability and contrast effects in vitro. This method is expected to be promoted and applied and provides a reference for ligand loading, potentially becoming an efficient and novel contrast agent. [ABSTRACT FROM AUTHOR]

Lane-changing behaviour is one of the complex driving behaviours. The lane-changing behaviour of drivers may exacerbate congestion, however driver behavioural characteristics are difficult to accurately acquire and quantify, and thus tend to be simplified or ignored in existing lane-changing models. In this paper, the Bik-means clustering algorithm is used to analyse the urban road congestion state discrimination method. Then, simulated driving tests were conducted for different traffic congestion conditions. Through the force feedback system and infrared camera, the data of driver lane-changing behaviours at different traffic congestion levels are obtained separately, and the definitions of the start and end points of a vehicle changing lanes are determined. Furthermore, statistical analysis and discussion of key feature parameters including driver lane-changing behaviour data and visual data under different levels of traffic congestion were conducted. It is found that the average lane-change intention times in each congestion state are 2 s, 4 s, 6 s and 7 s, while the turn-signal duration and the number of rear-view mirror observations have similar patterns of change to the data on lane-changing intention duration. Moreover, drivers' pupil diameters become smaller during the lane-changing intention phase, and then relatively enlarge during lane-changing; the range of pupil variation is roughly 3.5 mm to 4 mm. The frequency of observing the vehicle in front of the target lane increased as the level of congestion increased, and the frequency of observation in the driver's mirrors while changing lanes approximately doubled compared to driving straight ahead, and this ratio increased as the level of congestion increased. [ABSTRACT FROM AUTHOR]

Renewable lignocellulosic biomass is a favorable energy resource since its co-pyrolysis with hydrogen-rich plastics can produce high-yield and high-quality biofuel. In contrast to earlier co-pyrolysis research that concentrated on increasing product yield, this study comprehends the synergistic effects of two distinct feedstocks that were not considered earlier. This work focuses on co-pyrolyzing wheat straw (WS) with non-reusable polyethylene terephthalate (PET) for the production of pyrolysis oil. WS and PET were blended in different ratios (100/0, 80/20, 60/40, 40/60, 20/80, and 0/100), and pyrolysis experiments were conducted in a fixed-bed reactor under different temperatures to assess their synergistic effect on oil yield. Synergy rates of up to 7.78 % were achieved on yield for the blends of plastic and biomass at a temperature of 500 °C. In comparison to individual biomass or plastics, co-pyrolyzing PET-biomass blends demonstrated good process interaction and promoted the yields of value-added products. The heating value of the pyrolysis oils was in the range of 16.45–28.64 MJ/kg, which depends on the amount of plastic present in the feedstock. The physical analysis of the oils shows that they can be used for heat production by direct combustion in boilers or furnaces. The correlation between WS and PET was validated with the aid of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) analysis. The GC-MS result demonstrated the presence of different compounds such as O-H compounds, esters, carbonyl group elements, acids, hydrocarbons, aromatics, and nitrogenated compounds in the pyrolysis oil, which differed based on the proportions of PET in the feedstock. The increased hydrocarbon and reduced oxygen percentages in the pyrolysis oil were implicitly caused by enhanced hydrocarbon pool mechanisms, in which the breakdown of PET may be supplied as a hydrogen donor. Overall, waste lignocellulosic biomass and plastics can be used to produce biofuels, which helps reduce the amount of solid waste that ends up in landfills. This study also revealed that future research should be focused on the reaction mechanisms of WS and PET co-pyrolysis in order to examine the synergistic interactions.

Bug handling is an essential part of the software development process. Ideally, in a bug‐tracking system, bugs are reported, fixed, verified, and closed. In some cases, bugs have to be reopened mostly due to an incorrect fix. However, instead of reopening the existing bug report, users may submit a new report for a previously reported bug, which results in duplicate bug reports. Users might report duplicate bugs if they miss the previous bug report or if the previous bug is unresolved (i.e., in progress) and therefore cannot be reopened. These duplicate bug reports may cost extra maintenance efforts in triaging and bug fixing. There have been several studies on characterizing reopened bugs and duplicate bug reports; however, to the best of our knowledge, there has been no prior work on understanding the dynamics of their interaction, which is missed reopen bugs. Our study is based on analyzing the difference between duplicate and nonduplicate bugs and further categorizing the duplicate bugs. In this regard, we categorize duplicate bugs according to the original bug's resolution status at the duplicate's creation time as Master‐Unresolved bugs and Master‐Resolved (Missed Reopen) bugs to distinguish their properties. We compare these two types of bugs in terms of their relationship to their master bug, bug surface time, bug fix time, bug's severity, and the number of users involved. We perform case studies using the Eclipse and Mozilla projects' bug repositories that include more than 165,500 and 394,000 bug reports, respectively. Additionally, we investigate the perceived importance, impact, and causes of duplicate bugs, as well as the difference between nonduplicate and duplicate bugs and its categories for practitioners in the software industry by conducting a survey. [ABSTRACT FROM AUTHOR]

Many studies available in the literature focus mainly on the mechanical characterization of fiber, leaving out other physicochemical and thermogravimetric analyses that allow for establishing its potential as an engineering material. This study characterizes fique fiber for its potential use as an engineering material. The fiber's chemical composition and physical, thermal, mechanical, and textile properties were analyzed. The fiber has a high holocellulose content and low lignin and pectin content, indicating its potential as a natural composite material for various applications. Infrared spectrum analysis revealed characteristic bands associated with multiple functional groups. The fiber had monofilaments with diameters around 10 μm and 200 μm, as determined by AFM and SEM images, respectively. Mechanical testing showed the fiber could resist a maximum stress of 355.07 MPa, with an average maximum strain at which breakage occurs of 8.7%. The textile characterization revealed a linear density range of 16.34 to 38.83 tex, with an average value of 25.54 tex and a regain of 13.67%. Thermal analysis showed that the fiber's weight decreased by around 5% due to moisture removal in the range of 40 °C to 100 °C, followed by weight loss due to thermal degradation of hemicellulose and glycosidic linkages of cellulose ranging from 250 to 320 °C. These characteristics suggest that fique fiber can be used in industries such as packaging, construction, composites, and automotive, among others. [ABSTRACT FROM AUTHOR]

Copyright of Anadolu Tarım Bilimleri Dergisi is the property of Ondokuz Mayis Universitesi, Ziraat Fakultesi 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.)

In this work, the finest waste resulting from rock cutting and polishing processes, i.e., sawing sludges, is used as precursor to produce inorganic polymeric binders known as alkaline activated materials. The selected mix designs were characterized from a mineralogical, microstructural, chemical, physical (pH and electrical conductivity) and mechanical (compressive and flexural strength) point of view with satisfying results. The obtained outcomes give a complete overview of their potential application in the construction and conservation/restoration fields, promoting the valorisation of industrial wastes in the optic of circular economy and sustainability. • Reuse of industrial waste in the Alkaline Activation process is studied. • Synthetization process and binders' formulations are presented. • Minero-structural and physico-mechanical characterization of the binders is reported. • Future perspectives and sustainable applications are reported. [ABSTRACT FROM AUTHOR]

Lime is an ancient construction material that has been utilized throughout the world in various forms, providing stable construction methods in usable conditions. Lime mortar is well known for its low carbon footprint in production and carbon absorption throughout its lifespan as a hardened material. The significant benefits of lime mortar were analyzed and reviewed for further research. Ancient lime constructions need proper maintenance for aesthetic and structural strengthening to preserve this cultural architecture of national pride. Hence, the characterization of ancient mortars is mandatory for renovation work. Here, we studied the various characterization methods available worldwide. We analyzed samples taken from the 1900-year-old Vedapureeswarar Temple of Thiruvothur, Cheyyar, and the 1800-year-old Lakshmi Narasimhar Temple of Parikkal, located in Tamil Nadu. Hardened samples from these two ancient temples were collected and analyzed. The mineralogical characterization of these mortars using SEM, XRF, FTIR and XRD gave immense knowledge of the mortar matrix. Experimental analysis indicated that using natural organic materials in the lime has made the structures more potent and stable. The characterization study provided information on the ratio of mortar mix used, the presence of organic ingredients, and the need for compatible repair materials for proper maintenance of the temple structures. The characterization study furthers the necessary knowledge to provide a compatible repair material and indicates the need for ancient construction technology in the current highly polluted environment. [ABSTRACT FROM AUTHOR]

Due to the important role that reference materials (MR) play in the quality assurance system of food analysis laboratories, this research aimed to develop and evaluate a whole milk powder reference material for protein measurement. The homogeneity, stability, and characterization studies were carried out following the recommendations of the ISO 35:2017 Guide and the NTC-ISO 13528:2017 Standard. The homogeneity study was carried out using a sample of 10 units under reproducibility conditions, the short-term stability study was carried out at a storage temperature of 27 °C for 2 months following an isochronous design. The characterization strategy consisted of transferring the value of a very similar MR using a single method performed by a laboratory. The applied statistical analysis allowed us to determine the homogeneity and stability of the total protein parameter during transport. Finally, the assignment of the property value of the material was 25.99 g/100g of total protein with an estimated uncertainty U = ± 0.90 g/100 g. [ABSTRACT FROM AUTHOR]

Copyright of Materials & Technologies / Materiali in Tehnologije is the property of Institute of Metals & Technology 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 highly compressible nature of sludge and the presence of colloidal particles cause difficulties in sludge dewatering. Reducing the moisture content in secondary sludge is a key factor in reducing the capital costs, operational costs, and transportation costs in wastewater management. This investigation concerned the combined utilization of quicklime and granulated blast furnace slag (GBFS) to improve sludge dewatering. The experimental work included the initial characterization of the sludge and granulated blast furnace slag and evaluation of the dewatering ability of the treated sludge (CST, moisture content, turbidity, zeta potential, and heavy metal and biopolymer contents). Optimization using the Box-Behnken design (BBD) was carried out with various operational parameters, and the best performance was found to be at a pH of 10.2, a dose of 0.34 g/g DS, and a contact time of 14 min. A characterization study was carried out by scanning electron microscopy (SEM) in conjunction with EDS, X-ray diffractometry (XRD), and Fourier transform infrared spectroscopy (FTIR) to confirm the structural features (dense), elemental composition, and the presence of different functional groups. Hence, this study concluded that the use of quicklime with granulated blast furnace slag is suitable for conditioning during sludge dewatering. [ABSTRACT FROM AUTHOR]

• 5 out of 13 mine tailings can possess chemical contribution as SCM. • 3 out of 13 mine tailings can possess physical contribution as SCM. • Mine tailings possess significantly different characteristics than CFA and cement. • Chemical and physical pretreatment can potentially optimize mine tailings usage. In order to reduce emissions of CO 2 from cement production and avoid severe environmental pollution from the deposition of mine waste, this study investigated the possibility of utilizing mine tailings as supplementary cementitious materials (SCM) for partially replacement of cement in concrete. This study provides a characterization study of mine tailings to evaluate their potential for contributing chemically or physically as SCM. 13 mine tailing samples were characterized in regards to chemical composition (XRF, Loss on Ignition, CaCO 3 and pH), mineralogical content (XRD) and physical characteristics (Grain size distribution, Specific Surface Area, SEM-analysis). The characterization study showed five mine tailings to possess potential chemical contribution as SCM based on their chemical composition (SiO 2 , Al 2 O 3 , Fe 2 O 3 and CaO) and amorphous content. Three mine tailings showed potential physical contribution as SCM based on grain size and grain morphology. The remainder mine tailing characteristics suggest that their potential as SCM may be improved by pretreatment such as milling and/or thermal treatment. [ABSTRACT FROM AUTHOR]

Oil palm fruit fibre (OPFF) was investigated for its potential and probability to remove heavy metal ion and dye from the aqueous solutions. Different operational parameters were studied under batch experiment. The effective pH to attain maximum adsorption of MG and Pb(II) by OPFF was around pH 4 to 5. The adsorption process was rapid at the beginning and slowly achieved equilibrium within 180 minutes and 120 minutes for MG and Pb(II), respectively. From the experimental result, the pseudo-second-order kinetic model provided better correlation compared to pseudo-first-order kinetic model with R2 > 0.999. Various isotherm equations, such as Langmuir, Freundlich, and BET isotherm models were used to analyze the adsorption isotherm result. The experimental data fitted well into Langmuir and BET isotherm models with R2 = 0.996 and 0.984, respectively. The maximum adsorption capacity of OPFF from Langmuir equation was 41.67 and 10.10 mg/g for MG and Pb(II), respectively. Besides, characterization study of OPFF which include point of zero charge (pHzpc), chemical modification on the functional group and surface morphology was also performed in this study. [ABSTRACT FROM AUTHOR]

This study provides data on the occurrence and distribution of rare earth elements, yttrium, and scandium (REY + Sc) in coals and non-coal lithologies associated with coals from various Colombian coalfields. A number of authors have characterized the REY + Sc content of various international coal deposits; however, no study to date has specifically addressed the REY + Sc content of Colombian coals, despite Colombia's prominence as a global coal producer. In this study, 24 samples were collected from seven coalfields and subjected to REY + Sc analysis, density fractionation, and modified release tests. Overall, the Colombian coals analyzed in this study have an average REY + Sc abundance of 45 ppm on a dry whole coal basis (459 ppm on a dry ash basis) whereas the non-coal lithologies have an average REY + Sc content of 222 ppm. In particular, materials collected from the Antioquia-Viejo Caldas coalfield were found to contain a relatively higher amount of REY + Sc (>100 ppm) relative to the rest of the samples, which may be attributed to the volcaniclastic character of the sediment associated with the seams. Moreover, test results from the density fractionation and modified release tests show that the inorganic constituents are the major hosts of REY + Sc in Colombian coals, which is reflected by a strong and positive linear relationship existing between REY + Sc and sample ash yields. • The occurrence and association of REY + Sc in various Colombian coal samples were investigated. • The average REY + Sc concentration in selected Colombian coal samples was determined. • Mineral component was suggested to be the driving factor for the enrichment of REY + Sc. • HREEs tend to be either organically associated or enriched in the fine minerals dispersed within the organic matrices. • Inherent organic REY + Sc values for tested Colombian coal samples were provided. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The particles ball milled into ultrafine particles to increase specific surface area. • Due to particle size reduction, the particles physical and strength properties improved. • The environmental impacts decreased due to ultra fine fly ash usage increased. • The Usege of Grinding aids were improves the particle size reduction, the grind ability, and reduce the energy consumption. Abstract The influence of Grinding Aid (GA) and Grinding Performance (GP) on Raw Fly Ash (RFA) have been analyzed by solid state route to obtain Chloride based Ground Fly Ash (CGFA). Particle size distributions of RFA and CGFA are studied and GP optimization occurred at 120 min. Crystal structures are examined by X-ray Diffraction (XRD) and found to be multiphasic. Crystallite size and microstrain measured using Williamson-Hall plot (from XRD pattern) reveal that reduction in size and lattice gets strained. Microstructure obtained by Scanning Electron Microscope (SEM) shows <5 μm grain size with a spherical shape. Normal consistency found to be increased for both RFA and CGFA when compared to a control sample, whereas setting time is getting increased for RFA and decreased for CGFA. In addition, optimized compressive strength of RFA (15%) and CGFA (45%) blended cement composite mortar shows the higher strength of 6% and 7% respectively. The ball mill grinding process using chloride based grinding aids can be adopted at high volume replacement of fly ash in cement manufactory. [ABSTRACT FROM AUTHOR]

Abstract The current study systematically analyzes the impact of solidity (σ) and number of blades (n) on the aerodynamic performance of 2-, 3- and 4-bladed Darrieus H-type vertical axis wind turbines (VAWTs). Solidity varies within the wide range of 0.09–0.36. A large number of operational parameters, i.e., tip speed ratio (λ), Reynolds number (Re), turbulence intensity and reduced frequency (K) are investigated to provide a deeper insight into the impact of σ and n on the dynamic loads on blades, the turbine performance and the wake. High-fidelity unsteady Reynolds-averaged Navier-Stokes (URANS) simulations, extensively validated with experiments, are employed. The results show that the turbine optimal tip speed ratio (λ opt) is invariant to a newly-introduced parameter ' σ λ 3 ', regardless of the turbine geometrical and operational characteristics. In addition, a new correlation is derived to estimate λ opt as a function of σ , which can also be employed to predict the optimal σ for a turbine with a given λ. It is also found that: (i) for constant-speed urban VAWTs, which due to the low mean wind speed in the urban environment, frequently operate at moderate to high λ , a relatively-low σ is optimal; (ii) an optimal VAWT is a moderately-high-solidity variable-speed rotor maintaining a relatively-low λ , where due to the large blade chord length the resulting Re and K are favorably high; (iii) within the turbine optimal operational range, turbine power coefficient (C P) is almost independent of n. The present findings support the optimal aerodynamic design of small-to large-scale VAWTs. Highlights • New insights on the impact of solidity σ and number of blades for VAWTs. • A new correlation for optimal tip speed ratio λ opt and σ. • λ opt is found to be invariant to ' σ λ 3 ' for different conditions. • In the optimal regime, power coefficient is almost independent of number of blades. • Reduced frequency is shown as a critical parameter on turbine power performance. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of paramelaconite, tenorite and their mixtures were deposited on fiberglass substrate by chemical vapor deposition and catalytically evaluated by isopropanol oxidation at low temperatures between 150 and 275°C. Copper oxides were deposited using bis(2,4-pentanedionato)copper(II) as a precursor and oxygen as carrier-reactant gas. Original crystalline phases deposited on fiberglass at different temperatures or formed subsequently were characterized by several analytical techniques. Films gave crystallite sizes from 6.5 to 8.4nm and a thickness around 230nm. The fiberglass with a paramelaconite film showed a relatively high catalytic activity, more than 40%, at 250°C. Nevertheless, the fiberglass with a tenorite film exhibited a catalytic activity of only 10% at the same temperature. Above 250°C the paramelaconite experienced a notable deactivation after which the catalytic activity decreased to 6.7% at 350°C and after this, the catalyst could not be reused. This activity loss was probably due to changes in the chemical phases on fiberglass by effect of temperatures above 250°C. [Copyright &y& Elsevier]

Cu2O–CuO and CuO thin films on a fiberglass substrate were prepared by chemical vapor deposition (CVD) and then catalytically evaluated by cyclohexane oxidation. The fiber with a Cu2O–CuO film showed a high catalytic activity at low temperatures, for example 43% at 350 °C, and a good selectivity to cyclohexanol production (37% at 300 °C). The fiber with a CuO film exhibited a higher catalytic activity, for example 48% at 350 °C, with a high yield of cyclohexanone (37% at 250 °C). A CuO/SiO2 catalyst with the same CuO content gave a result similar to the CuO/fiberglass system under the same conditions examined but, on the other hand cyclohexane was cleaved giving a higher selectivity to hexenes, 30% at 250 °C. The effect of reaction temperature on the catalytic activity and selectivity of cyclohexane oxidation were investigated. At 300 °C the steady-state catalytic performance of the CuO/fiberglass experienced a slight deactivation after 4 h time-on stream from 40% to 38% of conversion, after which, the catalyst could be reused apparently without any activity loss. [Copyright &y& Elsevier]

Mineralogical and technological characterization of ceramic raw materials from a new deposit located at Caxias city, Maranhão State—Brazil, was accomplished to determine their potential as raw materials for the ceramics industry in northeastern Brazil. The ceramic raw materials were collected from three different locations on the site and characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), differential thermal analysis (DTA), and thermogravimetry (TG). The XRF analysis of the fraction < 2 μm revealed that most samples had SiO2 (35–51 wt%), Al2O3 (19–29 wt%), Fe2O3 (2–21 wt%), MgO (0.7 to 4.5 wt%) and K2O (0.9 to 5 wt%) as components. Quartz, kaolinite, illite, hematite and montmorillonite were the main mineral phases identified. DTA and TG analysis confirmed the mineral identification. The technological potential of the ceramic raw materials was investigated by: cation exchange capacity (CEC), plastic behavior (Atterberg Limits), linear shrinkage at 950 °C (LSF), flexural strength (FS), apparent porosity (AP), water absorption (WA) and bulk density (BD). The main experimental results—WA (9–17%), AP (19–31%), FS (2.0–23 MPa), and the Atterberg limits—indicated that the ceramic raw materials investigated have high potential to be used to develop mass for red or structured ceramics, such as bricks and roof tiles. [ABSTRACT FROM AUTHOR]