• Ashworth Eaton opublikował 1 rok, 3 miesiące temu

    A nanocomposite was formed by combining graphene oxide (GO) with chromium-centered metal-organic framework (Cr-MOF) nanoparticles regulated by the dendrimer polyamidoamine (PAMAM). PAMAM can successfully regulate the synthesis of Cr-MOF; in doing so, the size of Cr-MOF is reduced, its original morphology is maintained, and it has good crystallinity. A simple ultrasonication method was used to make the Cr-MOF/GO hybrid nanocomposite. Various characterization methods confirmed the successful synthesis of PAMAM/Cr-MOF/GO nanocomposites. The PAMAM/Cr-MOF/ERGO modified electrode could be used with cyclic voltammetry (CV) and differential pulse voltammetry (DPV) to study the electrochemical behaviors of 1-hydroxypyrene (1-OHPyr). The results indicated that the constructed PAMAM/Cr-MOF/ERGO electrochemical sensor had a significantly enhanced electrocatalytic effect on the electrochemical reduction of 1-OHPyr compared with the sensors with no PAMAM and the ERGO sensor, which could be ascribed to the synergetic effect from the high porosity of Cr-MOF and the high conductivity of ERGO, as well as the further electron transport action of the nanocomposite. Under the optimal conditions, the reduction peak current and concentration of 1-OHPyr showed a good linear relationship in the range of 0.1-1.0 and 1.0-6.0 μM, and the detection limit of 1-OHPyr was calculated to be 0.075 μM. Moreover, the PAMAM/Cr-MOF/ERGO electrochemical sensor constructed in this paper can be expected to provide some instructions for the construction of electrochemical sensing platforms and wider potential applications.The energy absorption and toughening effect of cartilage could effectively protect bone from damage, and the enhancement mechanisms of cartilage on deformation resistance or strength need to be revealed. Using a self-developed in situ bending tester integrated with an optical microscope, in situ bending of the composite bone structure consisting of the cartilage layer and cortical and cancellous layers was carried out, accompanied by simultaneously obtained continuous morphological changes in diverse deformation layers. Although the bending resistance of pure cartilage layer was only 0.3 N, the significant enhancements of bone strength and ductility induced by the cartilage layer were experimentally revealed, as the peak loads and ultimate bending deflections of the composite structure increased by 1.49- to 2.14-fold and 1.43- to 2.12-fold, respectively. The scanning electron microscopy images of the composite bone structure at various locations with disparate stress conditions exhibited significant difference in crack sizes and degrees of tearing damage. The cartilage layer was verified to induce a layered tearing dimple feature to inhibit the crack propagation and further enhance the deformation resistance. The frequency shift comparison between the Raman spectroscopies of various microregions also indirectly verified the inhibition effect of the cartilage layer on the stress increment in the cortical layer.A high-performance elastomer was obtained by a multinetworking system of a covalent bond, hydrogen bond, and clay plane bond. By taking advantage of the characteristics of each cross-linking, the thermoplastic elastomer shows excellent compression set resistance, good flowability, and high tensile properties. The hydrogen bond gives flowability due to the bond cleavage under heating. The covalent bond contributes to the low compression set by prevention of polymer chain flow. Moreover, the clay plane bond affects the tensile properties by de-localization of the entire cross-link and increase of hysteresis energy between the clay plane surface and other cross-linking points. Furthermore, the self-healing properties and high heat resistance and recyclability were also observed.Magnetic nanoparticles have an important role as heat generators in magnetic fluid hyperthermia, a type of next-generation cancer treatment. Despite various trials to improve the heat generation capability of magnetic nanoparticles, iron oxide nanoparticles are the only approved heat generators for clinical applications, which require a large injection dose due to their low hyperthermia efficiency. In this study, iron oxide nanoclusters (NCs) with a highly enhanced hyperthermia effect and adjustable size were synthesized through a facile and simple solvothermal method. Among the samples, the NCs with a size of 25 nm showed the highest hyperthermia efficiency. Differently sized NCs exhibit inconsistent interparticle crystalline alignments, which affect their magnetic properties (e.g., coercivity and saturation magnetization). As a result, the optimal NCs exhibited a significantly enhanced heat generation efficiency compared with that of isolated iron oxide nanoparticles (ca. 7 nm), and their hyperthermia effect on skin cancer cells was confirmed.Chemical fibers such as glass fiber and aramid cover a large proportion of sound-absorbing composite materials on the current commercial market. These materials possess superior mechanical properties but have the disadvantages of high production costs and energy consumption and difficult recovery and degradation. In this paper, jute fiber and polypropylene were selected as raw materials, and a series of jute fiber-reinforced polypropylene composite materials were prepared by a mixing-hot-pressing process. The acoustic and mechanical performances of the composites with different fiber contents and fiber residue ratios were discussed. The results showed that the sound absorption coefficient values increased with the increasing fiber content and decreasing residual gum ratio. The mechanical properties varied inversely with the residual gum rate. With the increase of fiber content, the tensile and bending strengths first increased and then decreased. Therefore, the jute fiber-reinforced polypropylene composites can possess favorable sound absorption performance with no mechanical property penalty by adjusting the parameters properly, demonstrating that the composite materials have promising applications in the acoustic field.In order to study the release of cerium nitrate in a self-healing epoxy-based coating, poly (urea-formaldehyde) (PUF) microcapsules containing cerium nitrate were synthesized. The effects of healing agent concentration and weight percent of microcapsules in the epoxy resin were studied through the incorporation of microcapsules within an epoxy-based coating. The prepared microcapsules were characterized using thermogravimetric analysis and Fourier transform infrared spectroscopy and confirmed the successful encapsulation of cerium nitrate within PUF capsules. The self-healing performance of the prepared epoxy coating was investigated in 0.6 M NaCl solution using electrochemical impedance spectroscopy (EIS) tests. The EIS results indicated the successful release of encapsulated cerium nitrate from PUF microcapsules once the damage occurred in the epoxy coating, which led to effective self-healing of the epoxy-based coating. The presence of chlorine and cerium ions in the solution led to the precipitation of cerium hydroxides and oxides in the scratched area as a passive layer which hindered the corrosion in the damaged area. In addition, the EIS results showed that the healing performance of the coatings depends on the weight percent of microcapsules and the concentration of the self-healing agent. The highest self-healing performance was achieved for the maximum amount of microcapsule incorporation (10 wt %), while the increase in the microcapsule percent led to a decrease in the adhesion of the coating to the substrate.A shift from coal to liquefied natural gas for electricity generation can mitigate CO2 emissions and respond to the intermittent and variable characteristics of renewable energy. With this objective, numerical simulation was performed in this study to determine the optimal position of the methane injector and evaluate the achievable reduction in NO x emissions before applying methane cofiring to an existing 550 MW tangentially fired pulverized-coal boiler (Boryeong Unit 3). The combustion and NO x reduction in the furnace were intensively analyzed based on the methane cofiring rate (up to 40%). The optimal position of the methane injector was found to be inside the oil port based on the spatial distribution of NO x and the stoichiometric ratio along the furnace height. The NO x reduction rate was logarithmically proportional to the methane cofiring rate, and compared to the base case, a 69.8% reduction was achieved at the 40% cofiring rate. In addition, the fraction of unburned char at the boiler outlet was equivalent to that of the existing boiler as the increase in the flow rates of the close-coupled and separated overfire air improved fuel and air mixing. Simultaneously, methane cofiring led to a reduction in the total fuel loss and CO emissions. Finally, this study showed that the recommended optimum cofiring rate was 20% based on the furnace exit gas temperature. Under the 20% methane cofiring condition, the boiler achieved a 57.3% reduction in NO x emissions and a 7.4% improvement in fuel loss.As perceived, fiber-reinforced photocuring resins possess various distinctive advantages over traditional reinforced resin systems. This includes a rapid curing rate, energy efficiency, no volatile organic compounds, high strength, good thermal stability, and chemical resistance. Printing 3D composite objects using vat polymerization techniques has been a center of interest where photocuring resins are applied. In our present study, we have synthesized resorcinol-based diglycidyl ether, that is, a resorcinol-based epoxy resin, and further acrylated to the resorcinol epoxy acrylate oligomer. This oligomer was further formulated to photocuring resins using a suitable quantity of reactive diluents and photoinitiators. Now, three types of synthetic fibers, that is, glass fibers, nylon fibers, and polyester fibers, were incorporated in this formulated resin at different loading percentages. The oligomer synthesized was analyzed for structural conformation using Fourier transform infrared spectroscopy and 13C nuclear magnetic resonance. Further, we comparatively examined the rheological behavior of prepared formulations, and compatible formulations were applied to stereolithography 3D printers. Finally, physical, mechanical, thermal, transmittance, and morphological characteristics were comparatively analyzed for prepared UV-cured composites. The outcomes obtained during characterizations of UV-cured composites will be inevitably reflected in 3D-printed objects.As the most active and top producing area of coalbed methane (CBM) in China, the southern Qinshui Basin (SQB) is dominated by anthracite. Due to the low permeability of coals, plenty of non-gas-producing and low production CBM wells exist in the SQB. The permeability enhancement through some technological means is the key to increasing the CBM production of this area. In this paper, some typical anthracites were selected from the Daning block of the SQB to assess the effect of acidification treatments on permeability enhancement. The maceral composition determination shows that approximately 15% of minerals exist in the collected coal samples, and the X-ray diffractometer (XRD) results reveal that the minerals consist primarily of clay minerals, along with a little amount of quartz, calcite, and dolomite. Two types of acidizing fluids were used to conduct acidification treatments on the anthracites for different lengths of time. The N2 permeability of the anthracites before and after acidification was measured and compared. The results show that the original samples exhibit low permeability. As the acidification time increases, the permeability of all of the samples shows an increasing trend, and the acid sensitivity index I a increases rapidly first and then levels off, and finally approaches 1. After 48 h of acidification, the samples show an increase ranging from 8.75 to 22.67 times (avg. 14.3 times) the original permeability. The permeability enhancement of the SQB anthracites is mainly attributed to the dissolution of acid-soluble minerals in the cleat system of coal. The minerals in the cleats are completely or partially dissolved by the acids, generating some soluble and insoluble substances; when the fluid flows through, the cleat space is reallocated. Overall, the cleat demineralization by acids frees up a lot of cleat spaces, leading to an increase in cleat connectivity. As a result, the fluid movement becomes smooth and the permeability of coal improves.Fischer-Tropsch has become an indispensable choice in the gas-to-liquid conversion reactions to produce a wide range of petrochemicals using recently emerging biomass or other types of feedstock such as coal or natural gas. Herein we report the incorporation of novel Cu nanoparticles with two Fischer-Tropsch synthesis (FTS) catalytic systems, Fe/reduced graphene oxide (rGO) and Fe-Mn/rGO, to evaluate their FTS performance and olefin productivity in two types of reactors slurry-bed reactor (SBR) and fixed-bed reactor (FBR). Four catalysts were compared and investigated, namely Fe, FeCu7, FeMn10Cu7, and FeMn16, which were highly dispersed over reduced graphene oxide nanosheets. The catalysts were first characterized by transmission electron microscopy (TEM), nitrogen physisorption, X-ray fluorescence (XRF), X-ray diffraction (XRD), and H-TPR techniques. In the SBR, Cu enhanced olefinity only when used alone in FeCu7 without Mn promotion. When used with Mn, the olefin yield was not changed, but light olefins decreased slightly at the expense of heavier olefins. In the FBR system, Cu as a reduction promoter improved the catalyst activity. It increased the olefin yield mainly due to increased activity, even if the CO2 decreased by the action of Cu promoters. The olefinity of the product was improved by Cu promotion but it did not exceed the landmark made by FeMn16 at 320 °C. The paraffinity was also enhanced by Cu promotion especially in the presence of Mn, indicating a strong synergistic effect. Cu was found to be better than Mn in enhancing the paraffin yield, while Mn is a better olefin yield enhancer. Finally, Cu promotion was found to enhance the selectivity towards light olefins C2-4. This study gives a deep insight into the effect of different highly dispersed FTS catalyst systems on the olefin hydrocarbon productivity and selectivity in two major types of FTS reactors.A new class of trifluoromethylpyridine 1,3,4-oxadiazole derivatives (6a-6v) was obtained, and their antibacterial activities were evaluated. Some of them exhibited good activity, particularly 6a, which had the highest in vitro activity against Ralstonia solanacearum (R. solanacearum) and Xanthomonas axonopodis pv. citri (Xac). The half-maximal effective concentrations (EC50) were 26.2 and 10.11 μg/mL, respectively, which were lower than those of commercial thiodiazole copper (97.2 and 35.3 μg/mL, respectively). Furthermore, 6q showed much higher activity against Xanthomonas oryzae pv. oryzae (Xoo) with an EC50 value of 7.2 μg/mL; this was superior to bismerthiazol (57.2 μg/mL). Collectively, our findings provide a foundation for the development of trifluoromethylpyridine 1,3,4-oxadiazole derivatives.Hydroxides of superalkalis (particularly, K- and Na-related species) are shown for the first time to function as superbases. A new small series of hydroxides (XM n+1OH) is designed based on superalkali species (XM n+1) where M (K and Na) is alkali metal atoms, n is the maximal formal valence of the central atom X (F, O, and N), and n ≥ 1. To probe whether such fascinating polynuclear superalkali hydroxides (SAHs), especially the K- and Na-associated moieties are as basic as the representative alkali metal hydroxides (KOH, NaOH, and LiOH) as well as similar Li-based SAHs, a comprehensive computational exploration (in the gas phase) has been reported using the framework of an ab initio method. The ab initio calculations reveal that both the K- and Na-related SAHs consisting of larger gas-phase proton affinity (PA) and gas-phase basicity (GB) values demonstrate stronger basic character compared to the LiOH and Li-based SAHs. However, the available SAHs act as strong bases as well as superbases; among the proposeeoretically examined SAHs may pave alternative routes for the experimentally rewarding applications.The development of inexpensive and environmentally friendly graphene-like carbon is critical for its integration into industrial products. This work highlights the production of graphene-like carbon structures from calcium hydroxide. The chemical vapor deposition conditions to grow graphitic carbon on a calcium hydroxide catalyst are reported. Acetylene, steam, and calcium hydroxide are used to grow a crumpled carbon morphology. The crumpled carbon resulted in a high surface area of 1276 m2/g and high electrical conductivity (>105 S/m). Additionally, the significance and origin of the C 1s X-ray photoelectron spectroscopy (XPS) π-π* plasmon loss peak as it is related to high electrical conductivity is reported. A unique mechanism for the catalytic process involving calcium acetylide is proposed. Several deposition times, steam concentration, and catalyst morphology were tested to synthesize a variety of carbon morphologies from calcium-based materials. Crumpled carbon, hollow nanospheres, bamboo-like carbon nanotubes, multi-walled carbon nanotubes, and graphene fiber morphologies were all formed using calcium-based catalysts. Multiple reaction conditions, a scaled reaction (300 g), and catalyst recyclability were investigated. Calcium-based materials were then used as catalysts for the growth of other graphene-like carbons.In this study, variations in the free radical concentration, degree of swelling (Q), and extraction yield of Buertai coal (C%, 80.4%) in 11 solvents with different characteristics were determined to investigate the interaction between the coal and solvent, as well as the bond cleavage during solvent extraction. Derivative thermogravimetry (DTG) results for the residues and raw coal were compared to confirm whether the covalent bond breaks during solvent extraction. The free radical concentration decreases in certain solvents but increases in a few others. The relative free radical concentration, Q, and extraction yield are positively correlated. The charge-transfer capability of the solvent, and in particular its electron-donating capability, plays an essential role in influencing the interaction between the coal and solvent. The increase in the free radical concentration during solvent extraction can be attributed to (1) the formation or decomposition of charge-transfer complexes, (2) dissociation of charge-transfer complexes into radical ions, and (3) breakage of weak covalent bonds. DTG results show the occurrence of weak covalent bonds breakage at temperatures of 133.9-320.1 °C during solvent extraction due to the reduction of the bond energy caused by the formation of radical ions.About 75% of epithelial ovarian cancer (EOC) patients suffer from relapsing and develop drug resistance after primary chemotherapy. The commonly used clinical examinations and biological tumor tissue models for chemotherapeutic sensitivity are time-consuming and expensive. Research studies showed that the cell morphology-based method is promising to be a new route for chemotherapeutic sensitivity evaluation. Here, we offer how the drug resistance of EOC cells can be assessed through a label-free and high-throughput microfluidic flow cytometer equipped with a digital holographic microscope reinforced by machine learning. It is the first time that such type of assessment is performed to the best of our knowledge. Several morphologic and texture features at a single-cell level have been extracted from the quantitative phase images. In addition, we compared four common machine learning algorithms, including naive Bayes, decision tree, K-nearest neighbors, support vector machine (SVM), and fully connected network. The result shows that the SVM classifier achieves the optimal performance with an accuracy of 92.2% and an area under the curve of 0.96. This study demonstrates that the proposed method achieves high-accuracy, high-throughput, and label-free assessment of the drug resistance of EOC cells. Furthermore, it reflects strong potentialities to develop data-driven individualized chemotherapy treatments in the future.According to WHO, cervical cancer is considered as one of the most frequently diagnosed cancers and the fourth main source of cancer death in women in 2020 worldwide. Hence, there is a need for development of cervical cancer screening with new rapid and cost-effective methods. Although there are few methods available for HPV identification, these techniques are less sensitive, time-consuming, and costly. An ultra-sensitive, selective, and label-free DNA-based impedimetric electrochemical genosensor is developed in this study to detect HPV-18 for cervical cancer. Electrochemical analysis was performed for the characterization of the sensing platform and for the detection of analyte. A single-stranded 25mer oligonucleotide DNA probe was immobilized onto a nitrogen-doped carbon nanodot-modified ITO electrode. Furthermore, the hybridization event was measured by testing the complementary single stranded DNA sequence in the samples. The sensor could distinguish between complementary as well as non-complementary sequences. Herein, impedance quantification demonstrated a limit of detection of 0.405 fM. The developed genosensor showed high selectivity toward HPV-18 in the clinical samples. This sensing platform can be considered as a rapid and selective method for the screening of HPV-18.Electrochemical catalytic coal gasification experiments with Fuxin (FX) coal under a CO2 atmosphere were conducted to evaluate the effects of power and temperature on coal gasification and char structure evolution during electrochemical catalytic gasification (ECG). When the power was 400 W, with temperature increasing from 800 to 1000 °C, the CO content in the gas products increased by 8.16%, the H2 content increased by 8.39%, and the CH4 concentration in the gas products initially increased and then decreased. When the temperature is 900 °C, with power increasing from 0 to 400 W, the CO content in the gas products increased by 58.27%, the H2 content increased by 81.33%, and the CH4 concentration in the gas products increased from 1.31 to 2.37%. The gasification reactivity and the concentration of combustible gas generated during ECG were higher than those during common coal gasification. Thermal electrons play important roles in ECG. These electrons could promote ring opening reactions and aromatic compound cracking and inhibit aromatization reactions while increasing the number of oxygen-containing functional groups in char, consequently enhancing the char gasification reactivity.To meet the stringent emission regulations and fuel economy demands of the spark ignition (SI) engine, more and more new technologies such as turbocharging, variable valve actuation (VVA), and exhaust gas recirculation (EGR) are being developed. For the turbocharged SI engine, the high boost pressure can lead to higher laminar combustion velocity with higher maximum burned gas temperature, which induces more emissions; it also carries a risk of serious knocking, which can not only deteriorate the brake-specific fuel consumption (BSFC) but also destroy the engine. As is well known, the dilution mixture gas methods, which include VVA and EGR, are effective techniques to advance the combustion phase and suppress knocking in the SI turbocharged engines. The effects of VVA and EGR rates on the BSFC and combustion characteristics of an SI engine were analyzed through 100 groups of engine experiments, and the quantitative analysis of the influence saliency of VVA and EGR rates has been introduced. Then, the optimal level of each factor was obtained by a comprehensive balance method. The results indicated that the EGR rate has the most significant influence on the BSFC and CA50. At the same time, the BSFC was only 211.7 g/kWh, which has been improved significantly, and CA50 was 12.55° CA ATDC, which effectively enhances the knock resistance when applying the optimization parameters.Tumor necrosis factor α (TNF-α) is used as a biomarker for the diagnosis of various inflammatory and autoimmune diseases. In recent years, numerous approaches have been used for the qualitative and quantitative analyses of TNF-α. However, these methods have several drawbacks, such as a tedious and time-consuming process, high pH and temperature sensitivity, and increased chances of denaturation in vitro. Quenchbody (Q-body) is a fluorescence immunoprobe that functions based on the principle of photoinduced electron transfer and has been successful in detecting various substances. In this study, we constructed two Q-bodies based on a therapeutic antibody, adalimumab, to rapidly detect human TNF-α. Both sensors could detect TNF-α within 5 min. The results showed that the limit of detection (LOD) of TNF-α was as low as 0.123 ng/mL with a half-maximal effective concentration (EC50) of 25.0 ng/mL using the TAMRA-labeled Q-body, whereas the ATTO520-labeled Q-body had a LOD of 0.419 ng/mL with an EC50 of 65.6 ng/mL, suggesting that the Q-bodies could rapidly detect TNF-α with reasonable sensitivity over a wide detection range. These biosensors will be useful tools for the detection and monitoring of inflammatory biomarkers.Brown seaweeds usually contain alginate as a major polymer. The second major sulfated polymer in brown seaweeds is fucoidan, which has huge potential in medicinal applications. In this study, the photosynthetic pigments from Turbinaria decurrens were first extracted using chloroform/methanol in the ratio of 11 (v/v), followed by fucoidan extraction with yields of 5.58% (crude) and 1.28% (purified fucoidan) from the dry weight of seaweed, whereas alginate was extracted with a yield of 14.7% DW of seaweed. The isolated fucoidan possessing anticoagulation property was identified and characterized as (1-3)-α-l-fucopyranosyl residues with sulfate groups primarily at the C4 position and to a lesser extent at the C2 position, whereas in the case of galactose, at the C3 and C6 positions. The AgNPs synthesized using isolated fucoidan exhibit strong anticoagulant activity and possess a good antibacterial property against Gram-negative clinical bacteria. Functional groups such as O-H, C-H, and S=O associated with sugar residues in sulfated fucoidan are involved in the synthesis of the nanoparticles with a spherical shape, size ranging from 10 to 60 nm, and showing polydispersity. From this study, we conclude that fucoidan-coated anionic AgNPs synthesized from T. decurrens have tremendous potential in drug development.Microbial detection is crucial for the control and prevention of infectious diseases, being one of the leading causes of mortality worldwide. Among the techniques developed for bacterial detection, those based on metabolic indicators are progressively gaining interest due to their simplicity, adaptability, and, most importantly, their capacity to differentiate between live and dead bacteria. Prussian blue (PB) may act as a metabolic indicator, being reduced by bacterial metabolism, producing a visible color change from blue to colorless. This molecule can be present in two main forms, namely, the soluble and the insoluble, having different properties and structures. In the current work, the bacterial-sensing capacity of soluble and insoluble PB will be tested and compared both in suspensions as PB-NPs and after deposition on transparent indium tin oxide-poly(ethylene terephthalate) (ITO-PET) electrodes. In the presence of live bacteria, PB-NPs are metabolized and completely reduced to the Prussian white state in less than 10 h for soluble and insoluble forms. However, when electrodeposited on ITO-PET substrates, less than 1 h of incubation with bacteria is required for both forms, although the soluble one presents faster metabolic reduction kinetics. This study paves the way to the use of Prussian blue as a metabolic indicator for the early detection of bacterial infection in fields like microbial diagnostics, surface sterilization, food and beverage contamination, and environmental pollution, among others.Nitrous oxide (N2O) is one of the greenhouse gases that contribute to global warming. But, there are few methods for controlling N2O directly. It is essential to reduce N2O to solve environmental problems. In this study, we investigate the O2 concentration dependence of N2O decomposition under an argon-based gas mixture in a high-temperature thermal reactor. The gas concentrations are calculated using CHEMKIN. The results confirm that more N2O is converted to N2 or NO at lower O2 concentrations. Therefore, the conversion process is hindered by increasing the O2 concentration. We propose a modified parameter of N2O decomposition, and it is employed in the CHEMKIN calculations. With the modified parameter, the experimental results are in a similar tendency to the calculated results.Catalyzed light olefin oligomerization is widely used in petrochemical industries to produce fuels and chemicals. Light olefins such as propene and butenes are commonly selected as feedstocks. Solid phosphoric acid (SPA) and zeolite are representative acidic catalysts. Both the feedstocks and catalysts have an impact on the product composition. In this study, state-of-the-art instrumentation two-dimensional gas chromatography (GC × GC) coupled photoionization-time of flight mass spectrometry was employed to investigate the composition of dodecene products produced from olefin oligomerization. Information such as the olefin congener distribution, dodecene structural subgroup distribution, and individual dodecene isomers was obtained and utilized in the statistical analyses. By using specific data sets of the product composition, the distinguishment between SPA and zeolite catalysts as well as among the feedstocks was achieved by applying the unsupervised screening approaches (principal component analysis and hierarchical clustering analysis). The potential indicators of catalysts and feedstocks were selected by the feature selection methods (univariate analysis analysis of variance and multivariate analysis partial least squares-discriminant analysis).In this study, the preparation and desulfurization application of MnO2 and pyrolusite blending-modified activated cokes (ACM and ACP) were studied. Thermodynamic calculation shows that the blended metal oxides could be reacted with the solid carbon and gaseous products H2, CO, and CO2 for activation. The physicochemical properties of the blending-modified ACP and ACM responded considerably differently to preparation conditions. The blended metal oxide significantly improved the mesoporous structure of the modified activated cokes, as well as the surface acidic and basic functional groups. Different metal oxides played different roles in the pore structure and surface functional group evolution, and the current investigation indicates that MnO2 is more favorable than pyrolusite. The enhanced acidic and basic functional groups, coupled with the catalysis of metal oxides, improved the desulfurization performance of the modified activated cokes. The sulfur capacities of the prepared ACP and ACM were 47.9-208.9 and 119.4-205.9 mg/g, respectively, which were much greater than the sulfur capacity of the fresh activated coke.TiO2 is an attractive catalyst for the photocatalytic degradation of organic pollutants. However, owing to its large band gap, it can only be activated by ultraviolet (UV) light, which constitutes a small portion of solar energy. Therefore, there has been significant interest in extending its light absorption range from UV to visible light. In this study, fluorinated TiO2 hollow spheres (FTHSs) were prepared via a rapid and simple wet chemical process using ammonium hexafluorotitanate, and then FTHS/WO3 heterostructures with different weight ratios of the FTHS and WO3 nanoparticles were synthesized via a simple wet impregnation method. The formation of the hybrid structure was confirmed by various characterization techniques. The photocatalytic activity of the synthesized photocatalysts in the photodegradation of rhodamine B, a model pollutant, was evaluated under visible light irradiation. The FTHS/WO3 heterostructures exhibited significantly improved photocatalytic activity compared to the bare FTHS or WO3 nanoparticles. The photodegradation efficiency of the FTHS/WO3 heterostructure in the present study was up to 0.0581 min-1. Detailed mechanisms that lead to the enhanced photocatalytic activity of the heterostructures are discussed. In addition, comparative experiments reveal that the photodegradation efficiency of the FTHS/WO3 heterostructure under visible light irradiation is superior to that of the P25/WO3 heterostructure prepared from the commercially available TiO2 catalyst (P25) via the same impregnation method.Electrochemical studies of resorcinol-based acridinedione (AD) dyes with nonfluorophoric simple amino acids, glycine, alanine, and valine, were carried out in water. AD probes are classified into photoinduced electron transfer (PET) and non-PET-based dyes, wherein the electrochemical properties and photophysical and photochemical behavior vary significantly based on the nature of substituent groups and the nature of the solute. The oxidation potential of PET dye (ADR1) to that of non-PET-based dye (ADR2) differs significantly such that the addition of amino acids results in a shift of the oxidation peak to a less positive potential and the reduction peak to a lesser negative potential. The extent of shift of oxidation and reduction potential in PET dye is more pronounced than that of non-PET dye on the addition of valine rather than glycine. The variation in the shift is attributed to the presence of an electron-donating moiety (OCH3) group in the ninth position of ADR1 dye. Consequently, the quenching of fluorescence is observed in ADR2 with non fluorophoric amino acids that are authenticated by the shift of the anodic and cathodic peaks toward a lesser positive potential. Molecular docking (MD) studies of PET and non-PET dye with amino acids portray that neither hydrophobic interactions nor electrostatic or weak interactions such as van der Waals and pi-pi interactions govern the electrochemical nature of dye on the addition of amino acids. Furthermore, the formation of a conventional hydrogen bond between dye and amino acid is established from MD studies. The existence of dye-water-amino acid competitive hydrogen-bonding interactions is presumably well-oriented throughout the aqueous phase as observed through photophysical studies which support our electrochemical investigation.The conventional methods for controlling excess water production in oil/gas wells can be classified on the basis of the mechanism (pore-blocking mechanism and relative permeability modification) used. Gel systems developed on the basis of a pore-blocking mechanism completely block the pores and stop the flow of both oil and water, whereas a relative permeability modifier (RPM) only restricts the flow of a single phase of the fluid. The gel working on the basis of the pore-blocking mechanism is known as a total blocking gel. An invert emulsified (PAM-PEI) polymer gel is a relative permeability modifier system. The same invert emulsion system is tested as a total blocking gel system in this research work. The dual-injection technique (1st injection and 2nd injection) was used for this purpose. In this research work, the emulsion system was tested at a temperature of 105 °C. The core sections with drilled holes and fractures were used for the core flooding experiments, representing a highly fractured reservoir. The developed emulsified gel system was characterized using a dilution test, an inverted bottle test, microscopic images, and FTIR images. The emulsified polymer gel was tested using a core flooding experiment. After the 2nd injection, the postflood medical CT and micro-CT images of the core sections clearly showed the presence of two different phases in the core section, i.e., the oil phase and the gel phase. The core flooding experiment result indicates that the gel formed after the 2nd injection of the emulsion system can withstand a very high differential pressure, i.e., above 2000 psi. The gel did not allow any oil or water to be produced. Hence, the developed emulsified polymer gel system with the help of a dual-injection technique can be efficiently used as a total blocking gel for high-temperature reservoirs.Syngas with important industrial applications has explosive hazards because of its flammability. It is necessary and valuable to study the combustion and explosion characteristics of syngas under actual working conditions. To explore the effects of initial turbulence on the explosion limits and the flame propagation behavior of the syngas-air mixtures, the explosion limits were tested by the explosive limit instrument, and the flame propagation process in the spherical pressure vessel was recorded by a high-speed camera. By adjusting the rotating speed of the stirrer to obtain turbulence of different intensities, the explosion limit and flame propagation behavior of syngas under different turbulent conditions were analyzed. The explosion limit of syngas in the macro-static state was 9.5-76.1%, and its flame front was relatively smooth. However, with the increase in turbulence intensity, both the upper and lower explosion limits of syngas decreased. The disturbance of turbulence made the flame shape change. The flame front was wrinkled, and the flame boundary was blurred, which became more and more obvious with the increase in turbulence intensity. The maximum velocity and duration of flame propagation increased with the increase in turbulence intensity. Under the same turbulence intensity, the flame propagation velocity generally augmented first and then lessened.Tobacco use is the leading preventable cause of premature disease and death in the United States. Approximately, 34 million U.S. adults currently smoke cigarettes. We developed a method for automated sample preparation and liquid chromatography-tandem mass spectrometry quantitation of 14 tobacco-related analytes nicotine (NICF), cotinine (COTF), trans-3′-hydroxycotinine (HCTF), menthol glucuronide (MEG), anabasine (ANBF), anatabine (ANTF), isonicoteine (ISNT), myosmine (MYOS), beta-nicotyrine (BNTR), bupropion (BUPR), cytisine (CYTI), varenicline (VARE), arecaidine (ARD), and arecoline (ARL). The method includes automated solid-phase extraction using customized positive-pressure functions. The preparation scheme has the capacity to process a batch of 96 samples within 4 h with greater than 88% recovery for all analytes. The 14 analytes, separated within 4.15 min using reversed-phase liquid chromatography, were determined using a triple-quadrupole mass spectrometer with atmospheric-pressure chemical ionization and multiple reaction monitoring in negative and positive ionization modes. Wide quantitation ranges, within 1.2-72,000 ng/mL, were established especially for COTF, HCTF, MEG, and NICF to quantify the broad range of biomarker concentrations found in the U.S. population. The method accuracy is above 90% while the overall imprecision is below 7%. Finally, we tested urine samples from 90 smokers and observed detection rates of over 98% for six analytes with urinary HCTF and MEG concentrations ranging from 200-14,100 and 60-57,100 ng/mL, respectively. This high throughput analytical process can prepare and analyze a sample in 9 min and along with the 14-compound analyte panel can be useful for tobacco-exposure studies, in smoking-cessation programs, and for detecting changes in exposure related to tobacco products and their use.Shale gas is an important unconventional natural gas resource, and its reservoirs have pores with strong heterogeneity, which have an important effect on the adsorption and migration of shale gas, but the specific mechanism is still unclear. To further clarify the pore structure characteristics of shale gas reservoirs and the mechanism of their influence on CH4 adsorption capacity, marine shale samples from the Wufeng-Longmaxi formation of wells N1, N3, and N10 in Changning block, southern Sichuan Basin, China, were selected for total organic carbon (TOC), X-ray diffraction (XRD), N2 gas adsorption (N2-GA), CH4 gas adsorption (CH4-GA), and field emission scanning electron microscopy (FE-SEM). The Frenkel-Halsey-Hill (FHH) model and Slit Island Analysis (SIA) were used to calculate the fractal dimension of the pore system and different types of pores, and their relationship and influence on CH4 adsorption capacity were also discussed. The results show that the fractal dimension could reflect the complexity and heterogeneity of pores. According to the FHH model, fractal dimensions of the surface and structure of the pore system (D 1 and D 2, D 1 less then D 2) were obtained, and the pore structure was more complex than the pore surface. According to SIA, the surface fractal dimensions of four types of reservoir space (D DP, D OP, D IP, and D MF) decrease progressively, and their main body is 2.60-2.80, 2.40-2.65, 2.20-2.40, and 2.05-2.30. Organic pores and intergranular pores are the most abundant, and so D 1 is mainly related to D OP and D IP. In high-TOC samples, D 1 is close to D OP, while in low-TOC samples, D 1 is close to D IP. The complexity of the pore surface, D 1, and specific surface area have a positive correlation, and with the increase of pore surface complexity, methane adsorption capacity could be significantly improved. Therefore, D 1 may be used as a characterization parameter of CH4 adsorption capacity, which could provide some evidence to further clarify the adsorption mechanism of shale gas.The fabrication and characterization of single-molecule junctions provide a unique platform to study the physical phenomena of a single molecule, and the electrical characterization enables us to understand the electrical transport properties of a single molecule and guide the fabrication of molecular electronic devices. However, the electrical characterization of single-molecule junctions is sometimes insufficient to extract the structural information on single-molecule junctions, and an alternate method to address this problem is to characterize the mechanical properties of single-molecule junctions. Simultaneous measurement of mechanical and electrical properties can provide complementary information on single molecules to analyze the correlations of their electrical and mechanical properties in the evolution of single-molecule junctions. In this mini-review, we summarize the progress on the simultaneous characterizations of mechanical and electrical properties for single-molecule junctions, and discuss the challenges and perspectives of this research area.Wastewater-based epidemiology (WBE) estimates collective consumption or exposure to chemicals or pathogens by monitoring the substances excreted in the population’s wastewater. Advances in mass spectrometry (MS) and the application of some clinical diagnostic tools and proteomics to wastewater fingerprinting have been linked to the discovery of new biomarkers and indicators of population health and are broadening the scope of WBE that nowadays cover not only small molecule biomarkers but also genetic biomarkers, large molecules, viruses, infection diseases, resistance, etc. This mini-review highlights recent WBE advances using MS and how this progress can create a fingerprint of a city’s health hazards, habits, and lifestyle, which is gaining in public health emphasis.This paper provides a mathematical model that makes it clearly visible why the underestimation of r, the fraction of asymptomatic COVID-19 carriers in the general population, may lead to a catastrophic reliance on the standard policy intervention that attempts to isolate all confirmed infectious cases. The SE(A+O)R model with infectives separated into asymptomatic and ordinary carriers, supplemented by a model of the data generation process, is calibrated to standard early pandemic datasets for two countries. It is shown that certain fundamental parameters, critically r, are unidentifiable with this data. A general analytical framework is presented that projects the impact of different types of policy intervention. It is found that the lack of parameter identifiability implies that some, but not all, potential policy interventions can be correctly predicted. In an example representing Italy in March 2020, a hypothetical optimal policy of isolating confirmed cases that aims to reduce the basic reproduction number R 0 of the outbreak from 4.4 to 0.8 assuming r = 0, only achieves 3.8 if it turns out that r = 40%.Childhood acute lymphoblastic leukemia (ALL) is a significant clinical problem that can be effectively treated with vincristine, a vinca alkaloid-based chemotherapeutic agent. However, nearly all children receiving vincristine treatment develop vincristine-induced peripheral neuropathy (VIPN). The impact of adolescent vincristine treatment across the lifespan remains poorly understood. We, consequently, developed an adolescent rodent model of VIPN which can be utilized to study possible long term consequences of vincristine treatment in the developing rat. We also evaluated the therapeutic efficacy of voluntary exercise and potential impact of obesity as a genetic risk factor in this model on the development and maintenance of VIPN. Out of all the dosing regimens we evaluated, the most potent VIPN was produced by fifteen consecutive daily intraperitoneal (i.p.) vincristine injections at 100 µg/kg/day, throughout the critical period of adolescence from postnatal day 35 to 49. With this treatment, vincristine-treated animals developed hypersensitivity to mechanical and cold stimulation of the plantar hind paw surface, which outlasted the period of vincristine treatment and resolved within two weeks following the cessation of vincristine injection. By contrast, impairment in grip strength gain was delayed by vincristine treatment, emerging shortly following the termination of vincristine dosing, and persisted into early adulthood without diminishing. Interestingly, voluntary wheel running exercise prevented the development of vincristine-induced hypersensitivities to mechanical and cold stimulation. However, Zucker fa/fa obese animals did not exhibit higher risk of developing VIPN compared to lean rats. Our studies identify sensory and motor impairments produced by vincristine in adolescent animals and support the therapeutic efficacy of voluntary exercise for suppressing VIPN in developing rats.Ongoing Coronavirus epidemic (COVID-19) identified first in Wuhan, China posed huge impact on public health and economy around the globe. Both cough and sneeze based droplets or aerosols encapsulated COVID-19 particles are responsible for airborne transmission of this virus and caused an unexpected escalation and high mortality worldwide. Current study intends to investigate the correlation of COVID-19 epidemic with meteorological parameters, particularly temperature and humidity. A data set of Epidemiological data of COVID-19 for highly infected provinces of Pakistan was collected from the official website of (https//www.covid.gov.pk/) and weather data was collected from (https//www.timeanddate.com/) during the time period of 1st March to 30th September 2020. The GrapPad prism 5 Software was used to calculate the mean and standard error of mean (SEM). In the current study the incident of daily covid cases is recorded higher in the month of June while the less number of case were reported in the month of May lated cities. These findings will be helpful for health regulatory authorities and policy makers to take specific measures to combat COVID-19 epidemic in Pakistan.Methane (CH4) is a greenhouse gas generated during the feed fermentation processes in the rumen. However, numerous studies have been conducted to determine the capacity of plant secondary metabolites to enhance ruminal fermentation and decrease CH4 production, especially those plants rich in tannins. This review conducted a descriptive analysis and meta-analysis of the use of tannin-rich plants in tropical regions to mitigate CH4 production from livestock. The aim of this study was to analyse the effect of tannins supplementation in tropical plants on CH4 production in ruminants using a meta-analytic approach and the effect on microbial population. Sources of heterogeneity were explored using a meta-regression analysis. Final database was integrated by a total of 14 trials. The 'meta’ package in R statistical software was used to conduct the meta-analyses. The covariates defined a priori in the current meta-regression were inclusion level, species (sheep, beef cattle, dairy cattle, and cross-bred heifers) and plant. Results showed that supplementation with tropical plants with tannin contents have the greatest effects on CH4 mitigation . A negative relationship was observed between the level of inclusion and CH4 emission (-0.09), which means that the effect of CH4 mitigation is increasing as the level of tannin inclusion is higher. Therefore, less CH4 production will be obtained when supplementing tropical plants in the diet with a high dose of tannins.

    and purpose Speech entrainment therapy (SET) is a computerized therapeutic approach that involves mimicking an audiovisual speech model to improve speech production. In a pilot study using SET for treatment of post-stroke non-fluent aphasia, significant gains were achieved in verbs per minute (VPM) during discourse using untrained items 1 and 6 weeks after treatment, suggesting that SET may yield meaningful improvements in fluent spontaneous speech for individuals with non-fluent aphasia

    The Speech Entrainment for Aphasia Recovery (SpARc) trial is a prospective, randomized, assessor-blinded, multicenter phase II clinical trial studying persons with chronic post-stroke non-fluent aphasia. Participants will be randomized to 3 weeks, 4.5 weeks, or 6 weeks of SET delivered via telehealth or a no SET control condition for 6 weeks. 80 adults (ages 21-81) with history of left hemisphere ischemic or hemorrhagic stroke with residual chronic (>6 months post stroke) non-fluent aphasia diagnosed by the Western Aphasia Battery-Revised (WAB-R) will be randomized (1111) over 4 years. The trial will be conducted at the clinical research facilities at three sites the Medical University of South Carolina, the University of South Carolina, and the University of Utah.

    This paper details the trial design of the SpARc trial, which aims to determine the dose of SET that will generate the highest effect size on speech fluency, VPM, sustained at 3 months post-treatment compared to a no SET control arm, for individuals with chronic post-stroke non-fluent aphasia to permit a future definitive trial to test the clinical utility of SET.

    This paper details the trial design of the SpARc trial, which aims to determine the dose of SET that will generate the highest effect size on speech fluency, VPM, sustained at 3 months post-treatment compared to a no SET control arm, for individuals with chronic post-stroke non-fluent aphasia to permit a future definitive trial to test the clinical utility of SET.

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