Lowecraven1402

The findings provide a better understanding of 5-FU resistance mechanisms and may enable the development of anticancer strategies that reverse the sensitivity of 5-FU resistance in CRC cells.The photocatalytic performance of common photocatalysts is limited by their low surface area, insufficient absorption of light energy, and fast photogenerated electron-hole recombination rate. The introduction of Z-scheme photocatalysts decorated with hexagonal boron nitride (h-BN) has already been confirmed to be an effective way to extend the surface area and increase the charge separation, thereby enhancing the photocatalytic performance. In this study, a hexagonal boron nitride (h-BN)-decorated WO3/g-C3N4 heterojunction photocatalyst was successfully synthesized via an in situ method using tungstic acid, melamine, and hexagonal boron nitride as the precursors. The physical and chemical properties of the resulting samples were thoroughly characterized. The surface, morphological, and optical properties of the resulting materials were thoroughly characterized by XRD, XPS, SEM, TEM, UV-vis DRS, BET surface areas, PL, and ESR analysis. The WO3/g-C3N4/BN composite exhibited a much higher photocatalytic activity for tetracycline degradation under visible light irradiation than pure g-C3N4, WO3, and BN. The favorable photocatalytic activity of WO3/g-C3N4/BN composites can be ascribed to the increased surface area and enhanced separation efficiency of photogenerated electron-hole pairs by adding h-BN nanosheets and forming the WO3/g-C3N4 heterojunction. This work indicates that the WO3/g-C3N4/BN photocatalyst is a promising material in wastewater treatment.Novel multifunctional biocomposite materials that mimic the properties of bone are the need of the hour. In view of this, the current work is focused on the fabrication of a snail shells derived europium-substituted hydroxyapatite (Eu-HAP)/poly(3,4-propylenedioxythiophene) (PProDOT)/Calotropis gigantea fiber (CGF) ternary composite on titanium (Ti) for biomedical applications. The structural, morphological, mechanical, electrochemical, and biological properties of the as-developed coatings on Ti were characterized. The obtained results clearly confirmed the formation and properties of the ternary composite (Eu-HAP/PProDOT/CGF). The presence of CGF, an exceptional reinforcement material, in the ternary composite is proven to improve mechanical and biological properties compared to other coatings (i.e., coating without CGF). Also, electrochemical studies revealed better anticorrosion properties of the composite-coated Ti in a simulated body fluid (SBF) solution. Similarly, the presence of Eu-HAP and PProDOT in the composite is clearly evident from the antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) and also by the cell proliferation and cell adhesion by the MTT assay test. Thus, we suggest that the fabricated Eu-HAP/PProDOT/CGF ternary composite with mechanical, corrosion resistance, and biocompatible properties might be an appropriate candidate for biomedical applications.An in silico study, using the GALAS algorithm available in ACD/PhysChem Suite, was performed to calculate the pK a(s) of various oximes with potential application as peptide coupling additives. Among the known oximes and predicted structures, OxymaPure is superior based on the pK a values calculated, confirming the results described in the literature and validating this algorithm for further use in that field. Among the nondescribed oximes, based on pK a calculation, ethyl 2-(hydroxyimino)-2-nitroacetate seems to be a potential candidate to be used as an additive during peptide coupling.Alloxan is a chemical generally administered to rats to induce diabetes mellitus, and pharmaceutical industries test the efficacy of their diabetic products on these rats. Alloxan is in a redox cycle with dialuric acid; hence, direct estimation of alloxan may not represent the actual concentration of the same in a given matrix. Also, in recent times, alloxan is added to food materials, especially to the all-purpose flour (maida) to bring softness and white color to the flour. Hence, consumption of food items made from such flour could induce diabetic mellitus in individuals, making it imperative to develop an accurate estimation of alloxan in food items. Herein, a voltammetric-based technique is developed to quantify the alloxan in refined wheat flour (maida) using an unmodified glassy carbon electrode (GCE). The electrochemical method offers rapid sensing while the use of an unmodified GCE surface offers repeatability and reproducibility between measurements. First, alloxan is converted to its stable adduct alloxazine by the reaction with o-phenylenediamine. The alloxazine adduct is electrochemically active, and the concentration of alloxan is estimated as a function of alloxazine formed using the voltammetric technique. The common shortfall in alloxan detection mainly involves its short half-life (∼a minute) whereas the alloxazine adduct formed is stable over a period of time. Using the current approach, alloxan concentration ranging from 10 to 600 μM is detected with a sensitivity of 0.0116 μA/μM. A low limit of detection of 1.95 μM with a precision of 1.2% is achieved using the above method. Real sample analysis revealed the presence of alloxan in all-purpose flour (maida-refined wheat flour) and bread purchased from the local market to the values of 35.76 and 25.03 μM, respectively. The same is confirmed using the gold-standard colorimetric technique.In this paper, three kinds of carbon fiber papers (CFPs), including pure CFP, poly(tetrafluoroethylene) (PTFE)-treated CFP (PTFE-CFP), and microporous layer (MPL)-coated CFP (MPL-CFP), were used to investigate the effects of the surface structure on the water transport behavior in CFPs. Compared to pure CFP, applying PTFE on the CFP increases the breakthrough pressure by 0.2 times, while it decreases the water flow rate at initial penetration by 0.06 times, owing to the strong hydrophobicity of PTFE-CFP. The pore diameter of MPL-CFP reduces sharply after coating the MPL, which leads to increasing breakthrough pressure by 0.6 times. The Young-Laplace equation is applied to study the relationship between the structure (wettability and pore-size distribution) of CFPs and the water transport behavior (breakthrough pressure), and the results show that in addition to wettability and pore size, the pore-size gradient also plays a crucial role in water transport.Histamine is an important substance that can be applied as a parameter for allergic reactions and food freshness. This study develops a method to produce a histamine sensor based on electrodes modified using polyurethane-LiClO4. A sensor method was developed where this sensor was produced from polyurethane. The application of 4,4'-diphenylmethane diisocyanate (hard compound) and palm kernel oil-based monoester polyol (soft compound) to produce polyurethane (PU) based on bio-polyol. The addition of lithium perchlorate (LiClO4) was done in order to increase the conductivity of PU. The oxidation process was detected using cyclic voltammetry, whereas the electrochemical impedance spectroscopy was used to analyze the conductivity of the polymer. The polyurethane-LiClO4 was attached on a screen-printed electrode (SPE) within 45 min. Moreover, the 1% LiClO4-PU-SPE presented satisfactory selectivity for the detection of histamine in the pH 7.5 solution. The LiClO4-PU-SPE presented a good correlation coefficient (R = 0.9991) in the range 0.015-1 mmol·L-1. The detection limit was 0.17 mmol·L-1. Moreover, the histamine concentration of mackerel samples was detected by the PU-SEP-LiClO4. Several amine compounds were chosen to study the selectivity of histamine detection using SPE-PU-LiClO4. The interference was from several major interfering compounds such as aniline, cadaverine, hexamine, putrescine, and xanthine. The technique showed a satisfactory selective analysis compared to the other amines. A satisfactory recovery performance toward varying concentrations of histamine was obtained at 94 and 103% for histamine at 0.01 and 0.1 mmol·L-1, respectively. The application of PU-SEP-LiClO4 as an electrochemical sensor has a great prospect to analyze histamine content in fish mackerel as a consequence of PU-SEP-LiClO4 having good selectivity and simplicity.Cementing is an important operation in the drilling process. During the cementing process, mud cake, fracturing, perforation, and so on will cause holes in the cement sheath. Thereby, the size effect will reduce the cement strength, which will seriously affect the cementing quality. Several hole types were drilled to study the mechanical properties and damage mechanism of oil well cement. The stress distribution and failure process of cement containing a hole were studied using RFPA2D software. The experimental and simulation results demonstrate that an internal hole has an obvious effect on the cement performance. The hole will change the cement bearing capacity and affect the fracture direction. Three crack types exist tensile, shear, and far-field. Both 2 and 5 mm vertical eccentric holes can reduce the cement tensile stress. Furthermore, the specimen tensile strength decreases with an increase in the diameter of holes. Horizontal eccentric holes with diameters of 2 and 5 mm will increase the cement tensile strength. Among these, the sample L2-2 exhibits a long crack path, high energy consumption, and a remarkable enhancement effect.Raman spectroscopy has long been suggested as a potentially fast and sensitive method to monitor phytoplankton abundance and composition in marine environments. However, the pitfalls of visible detection methods in pigment-rich biological material and the complexity of their spectra have hindered their application as reliable in situ detection methods. In this study we combine 1064 nm confocal Raman spectroscopy with multivariate statistical analysis techniques (principle component analysis and partial leas-squares discriminant analysis) to reliably measure differences in the cell viability of a diatom species (Chaetoceros muelleri) and two haptophyte species (Diacronema lutheri and Tisochrysis lutea) of phytoplankton. The low fluorescence background due to this combined approach of NIR Raman spectroscopy and multivariate data analysis allowed small changes in the overall spectral profiles to be reliably monitored, enabling the identification of the specific spectral features that could classify cells as viable or nonviable regardless of their species. The most significant differences upon cell death were shown by characteristic shifts in the carotenoid bands at 1527 and 1158 cm-1. find more The contributions from other biomolecules were less pronounced but revealed changes that could be identified using this combination of techniques.Excellent biocompatibility and corrosion resistance of implants are essential for Ti6Al4V parts fabricated by selective laser melting (SLM) for biomedical applications. To achieve better corrosion resistance and biocompatibility of Ti6Al4V parts, the effects of SLM processing parameters on the corrosion resistance and the biocompatibility of Ti6Al4V parts are investigated by changing the scanning speeds and laser powers. The detailed influence mechanism of processing parameters on the properties of Ti6Al4V parts is studied from two aspects, including microstructure and defects. It is found that the corrosion resistance and biocompatibility of Ti6Al4V parts can be adjusted by changing the scanning speed and the laser power due to the constituent phase and the number and size of defect holes of Ti6Al4V parts. Compared with the laser power, the scanning speed has a stronger influence on the performance of the part, which can be used as "coarse tuning" based on the performance requirements. At the scanning speed of 1100 mm/s and the laser power of 280 W, Ti6Al4V parts with better corrosion resistance can be obtained.