Polyhydroxyalkanoates (PHAs) are aliphatic polyesters synthesized intracellularly by microorganisms as a carbon-storage substance. Among the various PHAs, 3-hydroxybutyrate (3HB)-based copolymers are crystalline polymers widely used as biodegradable plastics. Recently, PHAs containing α-carbon-methylated monomers, such as 3-hydroxy-2-methylbutyrate (3H2MB) and 3-hydroxy-2-methylvalerate (3H2MV), have been synthesized and characterized. However, a binary copolymer of 3HB and 3H2MV, P(3HB-co-3H2MV), had not yet been synthesized, and its material properties had not been investigated. In this study, P(3HB-co-11 mol% 3H2MV) (PHBMV11) was synthesized with recombinant Escherichia coli LSBJ, using trans-2-methyl-2-pentenoic acid as the 3H2MV precursor. The thermal properties of PHBMV11 were characterized using differential scanning calorimetry (DSC), and the results were compared with those of P(3HB-co-12 mol% 3-hydroxyvalerate) (PHBV12) to explore the effect of α-carbon methylation in the com... [more]

A series of mesoporous NiO catalysts with high specific surface area were prepared by a simple hydrothermal method and modified by cetyltrimethylammonium bromide (CTAB) as the crystal structure directing regent. The characterization with SEM, XRD, BET, and H2-TPR results demonstrated that the introduction of CTAB effectively improved the dispersion, specific surface area, and pore volume and redox ability of NiO, and thus exposed more active sites. Meanwhile, the NiO catalyst with a CTAB/NiSO4·6H2O molar ratio of 2/3 exhibited the better catalytic ozonation performance of toluene, formaldehyde, methanol, and ethyl acetate than NiO. The in-situ DRIFTS elucidated the reaction path of catalytic ozonation of toluene and indicated that the introduction of CTAB facilitated the complete oxidation of by-products into CO2 and H2O.

The natural hydrophilic property of leather makes it a possible growing substrate for microorganisms. Microorganisms such as bacteria, yeasts, and molds frequently grow on shoe lining leather, causing skin diseases, unpleasant odors, and discomfort for the wearers. To address these issues, herein, bio-synthesized silver nanoparticles from Piper betle L. leaf extract were applied as an antimicrobial agent to pig leather via the exhaustion method. The characterization of nanosilver-treated pig leather was performed using colorimetry, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), atomic absorption spectroscopy (AAS), and FTIR techniques. Evaluation of antimicrobial efficacy of the nanosilver-treated leather was both qualitatively and quantitatively assessed against two bacteria (Escherichia coli and Staphylococcus aureus) and two fungi (a yeast Candida albicans and a mold Aspergillus niger) in accordance with AATCC TM90, AATCC TM30, and ISO 16187:2013 sta... [more]

In view of the problem that the formation of deepwater wells in the study area leak easily, the mechanism of loss-circulation was studied in depth, and the loss-circulation plugging material SmartGel was developed with guar gum and its derivatives as the main synthetic raw materials. The gel process could be controlled by adjusting the dosage and temperature of gel accelerators. In order to adjust the gelling speed of SmartGel, GelRetarder and GelAccelerant were developed. The extrusion strength of SmartGel increased with the increase in SmartGel dose and decreased with the increase in temperature. As for the plugging performance of SmartGel, the sand bed test confirmed that the pressure capacity of SmartGel in the 80 °C sand bed can reach at least 7 MPa, which can meet the requirements of site construction. The PPT sand tray test and core flow meter simulation pore test showed that SmartGel has good bearing performance. As for the gel-breaking of SmartGel, low-temperature gel-breaking... [more]

Two novel separation methods have been presented for the concurrent assessment of flumethasone pivalate (FP) and clioquinol (CL) in their combinations in ear drop formulations or in the presence of phenoxyethanol preservative (PEP) in their cream formulations. The first method is an innovative thin-layer chromatographic (TLC) method. The optimal separation was accomplished via silica gel aluminum plates F254, with a mixture of benzene, ethyl acetate and formic acid (5:5:0.2, in volumes) as the mobile system. In Method II, a new ultra-high-performance liquid chromatographic method (UHPLC) with a photodiode array detector (PDA) was presented. A reversed-phase inertsil ODS 5 µm C 18 packed column (100 Å, 4.6 mm internal diameter (I.D.) × 50 mm) at 30 °C was employed. Elution was completed in 3 min. Unfortunately, greener solvents were tested as a mobile phase, but an asymmetric peak for CL was noted. In addition, the new UHPLC method has a priority over the old HPLC one by Sayed et al., 2... [more]

The development of oxygen evolution reaction electrocatalysts with a low cost, high activity, and strong stability is of great significance to the breakthrough of energy conversion technology. Herein, a composite material (NiCo(CA)@M) was obtained by growing nickel-cobalt nanoparticles on MIL-88A in situ by a simple two-step solvent thermal method. The results show that NiCo(CA)@M composite has rich active sites, and the formation of the composite induces charge redistribution between NiCo(CA) and MIL-88A, effectively reducing the reaction energy barrier, while growth in situ was conducive to the improvement of material stability. Impressively, the NiCo(CA)@M catalyst achieved a current density of 10 mA cm−2 in alkaline electrolyte required an overpotential of only 270 mV and the Tafel slope was 69 mV dec−1. At the same time, the NiCo(CA)@M catalyst had excellent stability at a current density of 10 mA cm−2, and after the 16 h i-t test, the catalyst still had 91.1% current density rete... [more]

Successfully replacing meat with plant-based options will require not only replicating the texture of muscular fibres, but also imitating the taste, aroma, and juiciness of meat as closely and realistically as possible. This study examines the impact of rapeseed oil on the textural properties of meat analogues. Pea protein and soy protein are chosen as model systems to assess the effect of rapeseed oil. Optical, mechanical, and rheological characterisation tests are conducted to investigate the oil droplet distribution, the gel strength, Young’s modulus, and the length of the LVE region. The hypothesis is that oil droplets will act as active fillers in the protein matrix, and thus, diminish the strength of the protein gel network. The results of this study show that rapeseed oil droplets act as inactive fillers, as they are not bound to both examined protein matrices. Soy protein extrudates display minimal changes, while pea protein extrudates are significantly affected by the addition... [more]

To analyze the influence of liquid-nitrogen cooling on the damage and failure of high-temperature granite, granite samples were heated to 150~600 °C for natural cooling and liquid-nitrogen cooling treatment. Brazilian splitting tests were carried out as the samples returned to room temperature, and basic tensile and energy evolution parameters were obtained. Acoustic emission signal parameters during loading were recorded. The experimental results showed that the heating process caused damage to the granite samples, and liquid-nitrogen cooling further increased the degree of damage. Specifically, the ultrasonic velocity of liquid-nitrogen-cooled samples was lower than that of naturally cooled samples at each heating temperature. With an increase in heating temperature, the AE ring-down counts of liquid-nitrogen-cooled samples were higher than that of naturally cooled samples. At the same heating temperature, the dissipated energy of naturally cooled samples was greater than that of liq... [more]

Ginger (Zingiber officinale Roscoe.) starch is a waste product generated during the extraction of bioactive compounds from ginger. This study aimed to treat ginger starch with different freeze−thaw cycles and explore the effect on the functional components, physicochemical properties, and structural properties of ginger starch. The results of the study showed that as the number of freeze−thaw cycles increased, the content of resistant starch, amylose, total starch, and recrystallization in ginger starch increased significantly (p < 0.05). Freeze-dried ginger starch exhibited a C-type crystal structure in the X-ray diffraction pattern. The Fourier-transform infrared spectroscopy results also showed that the value of A1047/1022 increased, indicating that the freeze−thaw cycle would increase the degree of starch recrystallization. In terms of physical and chemical properties, compared with gelatinized starch, freeze−thawed starch had low swelling power, high solubility, low peak viscos... [more]

In order to study the effect of freezing and thawing of liquid nitrogen on the mechanical and seepage characteristics of coal rock with different water content values, conventional triaxial loading tests on freeze−thawed coal samples with different water content values were carried out using non-contact digital image processing technology. The research results showed that with the same water content, the peak strength of a liquid nitrogen freeze−thawed coal sample was smaller than that of a non-freeze−thawed coal sample, and the Poisson’s ratio was larger than that of the non-freeze−thawed coal sample; compared with the non-freeze−thawed coal sample, the strain fluctuation and concentration in the stages of compression density, elasticity, yield, and damage were weakened after freeze−thawing by liquid nitrogen, but the local stress concentration was more obvious; the non-freeze−thawed coal sample mainly showed single shear damage, and the damage fissures were inclined fissures with sma... [more]

Calcium sulfate whiskers (CSWs) were synthesized using purified flue-gas desulfurization (FGD) gypsum as raw materials using a hydrothermal method, where the filtrate was recycled back to the reaction slurry. The study investigated the impact of pH and Cu2+ concentration in the reaction solution with or without reagent compensation. The effects of cycle number on the crystal morphology, phase structure, and productivity of the hydrothermal products were also examined. The findings indicate that the crystal morphology and quality of the CSWs deteriorated as the cycle number increased due to a rise in pH and a decrease in Cu2+ concentrations in the reaction solution without reagent compensation. However, adding a specific amount of H2SO4 and CuCl2 to the slurry with filtrate recycle maintained the long fibrous shape of the hydrothermal products for up to seven cycles while also increasing their productivity from 73.7% to 86%. Regardless of reagent compensation, the cycle number of filtra... [more]

Focusing on the problem of drilling fluid loss circulation due to fractured granite formation in ultra-deepwater drilling in the research area, a novel self-degrading loss-circulation material is developed with polymer resin as the core material, according to the principles of loss-circulation prevention and reservoir and environmental protection. The relevant properties of the novel self-degrading loss-circulation material are evaluated by using tests or experiments. The pressure-bearing properties are evaluated by using a sealing capability test; the self-degrading properties are evaluated by using a self-degrading performance test; the pressure-bearing capability and reservoir protection properties are tested by measuring pressure sealing and gas permeability. The results of the tests and experiments show that the grinding rate of the loss-circulation material is less than 6% under 25 MPa, indicating that the novel loss-circulation material is of high compressive strength. The degra... [more]

The functional significance of cytochrome P450s (CYP) enzymes is their ability to catalyze the biotransformation of xenobiotics and endogenous compounds. P450 enzymes catalyze regio- and stereoselective oxidations of C-C and C-H bonds in the presence of oxygen as a cosubstrate. Initiation of cytochrome P450 catalytic cycle needs an electron donor (NADPH, NADH cofactor) in nature or alternative artificial electron donors such as electrodes, peroxides, photo reduction, and construction of enzymatic “galvanic couple”. In our review paper, we described alternative “handmade” electron sources to support cytochrome P450 catalysis. Physical-chemical methods in relation to biomolecules are possible to convert from laboratory to industry and construct P450-bioreactors for practical application. We analyzed electrochemical reactions using modified electrodes as electron donors. Electrode/P450 systems are the most analyzed in terms of the mechanisms underlying P450-catalyzed reactions. Comparativ... [more]

Due to the involvement of hazardous materials and the potential serious accidents that may occur in petrochemical plants, it is of great significance to develop real-time state evaluation methods offering high performance. Data-driven methods have received widespread attention following the development of advanced condition-monitoring systems. However, scarce training samples evaluated under multiple operating conditions are available because of the high stability and reliability requirements of petrochemical plants. In this paper, a real-time state evaluation method based on the technique for order preference by similarity to ideal solution (TOPSIS) is proposed, which circumvents dependence on data samples. First, the positive and negative ideal solutions of TOPSIS are determined using expert experience and the process index control limits of process cards. Then, fixed-value and fixed-interval indices are proposed to address the interval-optimal parameters. Subsequently, a new combine... [more]

Administration through the respiratory tract can be advantageous, with high drug bioavailability, limited enzymatic activity, reduced dose requirements compared to oral, and potentially diminished side effects. Among the different types of drugs studied for pulmonary delivery, genetic material delivery has gained favorable scientific interest, using polymer-, lipid-, inorganic-, or vector-based nanocarriers. As pulmonary drug delivery has been associated with challenges, including physiological barriers and lung metabolism, the delivery of sensitive molecules such as nucleic acids can exacerbate these challenges. While short-interfering RNAs (siRNAs) have been extensively reported as suitable ribonucleic acid interference (RNAi) candidates for pulmonary delivery, discussion on micro-RNA (miR) pulmonary delivery is limited despite their significant therapeutic potential. Recently, these non-coding RNAs have been explored in targeted or non-targeted pulmonary administration against vario... [more]

Phytoecdysteroids are a group of naturally occurring ecdysteroid hormones found in certain plant families and used for centuries for their adaptogenic, tonifying, and antioxidant properties. Ecdysterone and turkesterone are the dominant phytoecdysteroids found in the plant species Rhaponticum carthamoides Willd., Cyanotis arachnoidea C.B.Clarke and Ajuga turkestanica (Regel) Briq., and have been recognized for their adaptogenic potential and ability to enhance physical performance. However, over the past few years, supplementation with ecdysterone by professional athletes has raised some concerns about its safety and quality, leading to its inclusion in the World Anti-Doping Agency monitoring program. This study proposes a simple and reliable method for quality control of ecdysterone- and turkesterone-containing products using high-performance liquid chromatography (HPLC) analysis. The HPLC method is based on reversed-phase chromatography and gradient elution to achieve a superior sepa... [more]

Silicon is considered to have significant potential for anode materials in lithium−ion batteries (LIBs) with a theoretical specific capacity of 4200 mAh g−1. However, the development of commercial applications is impacted by the volume shift that happens in silicon when charging and discharging. In this paper, a yolk−shell−structured Si@void@C anode material has been developed to address this problem. The silicon nanoparticle yolk material is obtained by recycling kerf loss (KL) Si waste from the process of slicing silicon block casts into wafers in the photovoltaic industry; the carbon shell is prepared by a hydrothermal method with glucose, and the sacrificial interlayer is Al2O3. The produced material is employed in the production of anodes, exhibiting a reversible capacity of 836 mAh g−1 at 0.1 A g−1 after 100 cycles, accompanied by a Coulomb efficiency of 71.4%. This study demonstrates an economical way of transforming KL Si waste into materials with an enhanced value for LIBs.

The application of liquid−liquid chromatography principles to solvent extraction processes in hydrometallurgy can greatly simplify rare earth metal separation technologies by separating multicomponent mixtures in one technological operation. In this study, the chromatographic separation of rare earth elements (REEs) in multistage extraction columns was experimentally studied under conditions of impulse sample injection—single and multiple loading of large volumes of metal salt solution into the installation. The results obtained showed the feasibility of operating sieve plate extraction columns in the liquid−liquid chromatography mode. A closed-loop recycling technology is proposed for the separation of rare earth elements in multistage extraction columns operating in the liquid−liquid chromatography mode. For further development and industrial implementation of this technology, experimental studies should be conducted on intensified multistage extraction columns, such as sectioned col... [more]

Nickel-rich ternary cathode materials (NRTCMs) have high energy density and a long cycle life, making them one of the cathode materials of LIB that are currently receiving much attention. However, it has shortcomings such as poor cycling performance (CP) and a high-capacity decay rate. Because of this, the study analyzed the modification effect of WO3 on NRTCM lithium batteries by preparing WO3-modified poly-crystal and single-crystal NCM622 materials under the existing conditions of better original cathode materials as reference samples. The results showed that in the morphology and structure testing, with the increase of WO3 addition, the c/a values of all NCM622-WO3 samples were greater than 4.95. In the analysis of cycling and rate performance (CRP), as W increased, the rate performance (RP) of the NCM622-W4.0 sample had a discharge specific capacity ratio of 86.2% at 10.0 C/1.0 C. In cyclic voltammetry testing, when the addition amount of WO3 was 1.0%, the polarization degree of S... [more]

This study presents a comprehensive material balance equation (MBE) to estimate the reserve of shale gas reservoirs including free and adsorbed gas volume. The presented material balance equation takes into account the effect of stress change, matrix shrinkage, water volume production and influx, and critical desorption pressure. The material balance equation is converted into a linear relationship between the reservoir production and expansion parameters used during the derivation procedures that include rock-fluid properties and production history data. The proposed straight line reserve evaluation technique yields a slope of original free and absorbed gas in organic matrix, while the y-intercept yields the volume of original free gas in the in-organic matrix. A field case study of shale gas located in Australia is presented. Results show that the proposed MBE and the corresponding straight line reserve evaluation technique are rational and competent in estimating the free gas and ad... [more]

This study investigates the Hagen−Poiseuille pipe flow of viscoplastic fluids, focusing on analytical predictions of concrete pumping using the shear-stress-dependent parabolic model, extending analytical studies to a nonlinear rheological model with easily accessible experimental parameters. Research novelty and highlights encompass solving the steady laminar pipe flow for viscoplastic fluids described by the parabolic model, presenting detailed results for the two-fluid parabolic model, and introducing a computational app implementing theoretical findings. The parabolic model outperforms linear models, such as the Bingham model, in accuracy by accounting for the nonlinearity in the flow curves (i.e., shear stress and shear rate relations) of pumped concrete. The influence of rheological parameters on these relations is analyzed, and their versatility is demonstrated by a Wolfram Mathematica-based application program. The analytical approach developed in this work is adaptable for oth... [more]

In this study, an ultrasonic-assisted electrochemical grinding (UAECG) system was designed to improve the low efficiency and tool wear in conventional grinding of hard and tough materials. In this system, multiple-field energy consisting of ultrasonic, electrochemical and mechanical grinding was used. The processing mechanism was investigated to determine the interaction mechanism between ultrasonic, grinding and electrochemical processing. The established theoretical model showed that the processing efficiency was affected by the ultrasonic amplitude, ultrasonic frequency, electrolyte conductivity and other parameters. In verifying the feasibility of UAECG machining and the effect of machining elements on machining, a series of corresponding machining experiments was conducted. Experiments showed that the machining efficiency can be improved by machining through the UAECG system. The material removal rate of W18Cr4V machining was 2.7 times higher than that of conventional grinding and... [more]

The stability of active pharmaceutical ingredients (APIs) and the corresponding pharmaceutical formulations are nowadays of great importance in pharmaceutical research and technology. The quality of an API or of finished pharmaceutical products (FPPs) is time dependent under the influence of several parameters, such as light and air exposure, temperature, and humidity. Additionally, the stability profile of an API is influenced by the formulation composition, due to the presence of excipients or by the characteristic of the packaging materials. In this sense, the main objective of this study was to analyze the degradation kinetics of the antihypertensive drug moxonidine as a pure ingredient (MOX) and in two different solid mixtures, one corresponding to a pharmaceutical formulation (MOXTAB) and the other to an enriched pharmaceutical formulation in MOX (MOXMIX). As investigation techniques, FTIR (Fourier transform infrared) spectroscopy and TG/DTG/HF analysis were employed, while the t... [more]

As is widely known, the issue of freshwater scarcity affects practically all people, and all are looking for innovative and workable ways to attempt to solve this issue. In this work, a novel method of desalination is proposed. The proposed system consists of a solar collector (PTSC), evacuated pipe (EP), condenser (CU), and separation unit (SU). The working principle of the system is heating the feed saline water using the PTSC and EP and controlling the water flow rate to control the output conditions of the EP. The produced vapor is therefore separated from salty water using the SU. In addition, the generated steam is condensed into the CU to produce a freshwater distillate. Consequently, the effect of solar radiation on the affecting temperatures was tested. In addition, the effect of using different water flow rates (6, 7.5, 10, 20, 40, and 60 L/h) inside the EP on the system productivity was investigated. The primary findings of this work may be highlighted in relation to the exp... [more]

Traditional wastewater treatment methods, such as reverse osmosis, adsorption, desalination, and others, are outweighed by the photocatalytic degradation of organic pollutants. Ferrites are prominent photocatalysts due to their tunable band gaps, surface areas, and magnetic properties, which render photodegradation economical. Ferrites and their nanocomposites have been reported as promising visible light active photocatalysts. The photocatalytic system is heavily reliant on a number of factors that influence the photodegradation of organic effluents. This review demonstrates various parameters such as substrate concentration, pH of solution, photocatalyst quantity, photocatalyst surface area, metal and non-metal ion doping, light intensity, irradiation time, quenchers, etc. affecting the photocatalytic degradation of organic effluents by ferrite nanoparticles and their nanocomposites in detail. The photodegradation efficiency of the ferrite nanoparticles alters with the change in the... [more]