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Biogas, landfill gas, associated petroleum gas, and other tail gases accompanying various industrial processes are potential sources of hydrogen and carbon monoxide for solid oxide fuel cells via the reforming process. As these gases contain heavy hydrocarbons, fine-tuning of steam and carbon dioxide addition and specific temperature control are necessary to avoid carbon deposition during the reforming process. Numerical simulation plays a crucial role in designing miniaturized steam reforming reactors and optimal working conditions. All simulations of reforming processes must account for carbon deposition. The methods commonly seen in the open literature include Gibbs free energy minimization or parametric equations formalism. This paper utilizes Gaussian process regression as a tool for making predictions about which reforming parameters are suitable for carrying out this process without the danger of damaging the catalyst due to a carbon formation. Parametric equations formalism and Gibbs free energy minimization involve either the minimization of objective function or a search for roots of nonlinear functions. These tasks are sensitive to a choice of the starting points of the algorithm — wrong choice of starting points could lead to numerical instability. Unlike conventional methods, the Gaussian process regression approach bypasses the computation of equilibrium composition. It predicts carbon formation tendencies directly from the initial conditions which ensure stability.

This research including a study of mechanical ,physical properties (band structure, density of states) and the elasticity constants of the Barium Ortho titanate by using Materials studio software. The calculations were based on the generalized gradient approximation (GGA) by linear method. The calculated equilibrium lattice constants of monoclinic barium orthotitanate were: a = 0.612nm, b = 0.77nm, c = 1.05nm,calculated bulk modulus =42.3021 GPa, young modulus= 40.29 GPa, share modulus = 15.97 GPa, lame constant (λ)= 142.56 GPa ,and energy band gap=3.435eV which is indirect band gap and the composite is insulator and the electronic properties where be calculated in first Brillion zone. According the mechanical stability conditions the composite is stable mechanically. These results were calculated by Materials studio software.

Fluoride contamination in groundwater is a major concern in many parts of India and all over the world. Researches paying attention for the removal of fluoride through the application of biosorbents prepared from different parts of plants are finding greater scope and importance. The present research work focuses on Senna auriculata L., flower petal biomass as biosorbent, and evaluated its feasibility for fluoride ion elimination from aqueous solutions. Batch experiments were conducted to remove fluoride under different experimental conditions have been optimized for the maximum removal of fluoride; 80% removal was observed at pH: 6, sorbent dosage: 0.25 g/100 mL, time of agitation: 90 min, and initial concentration of the fluoride ions: 5 mg/L. Characterization studies of the biosorbent revealed its favorability towards the sorption of fluoride. In the isothermal modeling studies, Langmuir isotherm model was obeyed by the biosorption process with R2 value of 0.98 and from a kinetic perspective, the biosorption of fluoride onto the biosorbent observed the pseudo-second-order reaction with R2 value of 0.98. The developed biosorbent has been applied to real field fluoride-contaminated water samples and found to be successful.

The prosthetic socket base material must have exhibited good mechanical properties. An experimental investigation about the behavior of different fibers reinforced laminated composite materials were done. This work has been done on seven laminated composites which were prepared by the Vacuum bagging technique from Polyester resin as a bonding matrix and reinforced with (Jute, Glass, Carbon, Perlon) fibers. Laminated specimens were characterized by mechanical tensile tests such as (Tensile Strength, Young’s Modulus, Elongation Percentage) and physical test (density) to measure specific strength and specific modulus. SEM test also had been studied for different laminated composite. The results of experimental work showed that the mechanical properties were changed with the type and number of reinforcing layers. So, the results showed that the best laminated composite specimens have three layers of Jute with four layers of Carbon fiber. Where tensile strength and modulus of elasticity reach (162 MPa. and 3.60 GPa.) respectively. And specific strength and specific modulus reach to (134 MPa.cm3/gm–2.544 GPa.cm3/gm). The smoothness of the fractured surface will increase, indicating a brittle to semi-ductile transformation, according to SEM results.

Glycine functionalized activated carbon adsorption material (NOPAC-GLY-X) was successfully prepared by one-step thermal decomposition using agricultural waste navel orange peel as a precursor. Through batch adsorption experiments, it is found that the adsorption performance of Gd(III) on activated carbon can be significantly enhanced by glycine modification. The adsorption isotherms of the NOPACs conformed to the Langmuir isotherm model, and the maximum adsorption capacity of the activated carbon sample NOPAC-Gly-60 is approximately 48.5 mg/g. The Gd(III) adsorption capacity of navel orange peel activated carbon can be doubled after glycine modification, and the adsorption efficiency of gadolinium can reach 99% at pH=7. The physicochemical properties of the prepared adsorbents were characterized by BET, FTIR, EA, and XPS. The characterization test shows that the specific surface area of the sample increases from 1121 to 1523 m2/g, and the ratio of (N+O)/C increases from 10.8% to 30.0% by the glycine modification. After five cycles of adsorption-desorption, the adsorption capacity can still be maintained at 88% of the initial capacity. NOPAC-GLY-60 has excellent adsorption selectivity for Gd(III). With the obvious advantages of simple synthesis steps and low cost, the activated carbon modification method adopted in this study has great application value in the field of rare earth adsorption and recovery.

Inexpensive Cu2ZnZnS4 (CZTS) films using a two-step method have been developed for use in photovoltaic devices. Gavalnostatic electroplating precursors from environmentally friendly electrolytes and sulfurization were implemented in this method. Optimized sequential electrodepositions of Cu, Sn, and Zn films were carried out on molybdenum-coated glass, while the sulfurization of Mo/Cu/Sn/Zn precursors was performed at 500 °C or 550 °C in a sealed quartz tube filled with argon. The produced CZTS films were characterized in detail by photoelectrochemical measurements (PECMs, as photoelectrocatalytic detections), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), Raman microspectroscopy, X-ray diffraction (XRD), and UV-Vis spectroscopy. PECMs revealed a photocurrent of “copper poor” CZTS sulfurized at 550 °C up to 1.5 mA/cm2, much higher than that of “copper rich” CZTS sulfurized at 550 °C (0.1 mA/cm2). SEM showed Sn particles were dispersed in the precursors, and the morphologies of “copper poor” CZTS showed less crevices and/or pinholes than those of “copper rich” CZTS. EDX analysis showed only Zn-loss could be found after the sulfurization. Raman imaging revealed the uniform composition of “copper poor” CZTS sulfurized at 550 °C, while “copper rich” CZTS processed at the same temperature contained binary compound SnS2 interposing the CZTS. The results of both XRD and Raman depicted that all CZTS films possessed kesterite structure. A direct band gap of about 1.45 eV for the produced CZTS film was determined from UV-Vis spectroscopy. All the measurements demonstrated that the CZTS film fabricated by galvanostatic electroplating meets the requirements for a light-absorbing layer and is a potential candidate for assembling CZTS solar cells. The J-V measurement of the resulting device confirms this assertion, and demonstrates a 5.0% conversion efficiency of the CZTS solar cell.

Sulfolane is an important aprotic polar solvent. Liquid-liquid equilibrium (LLE) data for the ternary systems of water + 1,2-dichloroethane + sulfolane were measured at temperatures of 288.15, 298.15 and 308.15 K under the atmospheric pressure. The distribution coefficient and selectivity were determined from the measured LLE data, which showed that 1,2-dichloroethane is a suitable extractant for the recovery of sulfolane from its aqueous solution. The nonrandom two-liquid (NRTL) model and the universal quasi-chemical (UNIQUAC) model were utilized to correlate the experimental LLE data. The low values of RMSD indicated that the ternary system could be fitted well by the NRTL and UNIQUAC models. The consistency of the binary interaction parameters for the two thermodynamic models obtained was confirmed by the topological information contained in the Gibbs energy of mixing function (GM/RT).

Heterogeneous two-dimensional layered membranes reconstructed from natural or synthetic van der Waals materials enable novel ion transport mechanisms by coupling with the chemistry and optoelectron...

Chromic oxide (Cr2O3) monolayer is a promising alternative hydrogen evolution reaction (HER) catalyst compared with expensive platinum (Pt) due to its advantages such as low cost, large specific surface area, high reserves, and designability. In this study, the two practical strategies, strain engineering and transition metal (TM) doping (Mn, Fe, Zn, etc.), are proposed to activate the catalytic sites of Cr2O3 monolayer for the HER. The density functional theory (DFT) calculations demonstrate that the strained Cr2O3 monolayer can stimulate the HER activity with the Gibbs free energy of hydrogen adsorption (ΔGH∗) close to 0.09eV, which can be considered as a performable strategy to tune the HER catalytic behavior of Cr2O3 monolayer. For the TM doping, it also plays a role in the performance adjustment. These results provide a guideline to optimize the HER performance of Cr2O3 monolayer.

Ionic liquids (ILs) have attracted increasing attention since last few decades due to their high molecular design abilities and wide applications in different fields. In this study, four novel fluorescent isoquinolino [2,1-a]quinoxalin-5-ium ILs were designed and synthesized via a two-step process including a simple dual Schiff's base formation and a subsequent [RhCp∗Cl2]2-catalyzed oxidative C–H activation/annulation reaction. The as-synthesized ILs were extensively characterized using FT-IR, 1H-NMR, 13C-NMR, 19F-NMR, HSQC-NMR, HMBC-NMR and HR-MS. Their photophysical properties were determined by steady-state fluorescence spectroscopy. The results demonstrate that all these ILs showed dual or triple emissions, large stokes shift (90 nm) and mechanochromic behaviors. Basing on solvatochromism and titration experiments, it is thought that the emission bands of the ILs are raised from their local excited states, charge transfer states or excited state proton transfer of cations, while the substitute effect of these quinoxaline derived ILs on their stokes shifts is negligible.

The present work aimed to investigate the electrochemical properties of ITO substrates in propylene carbonate (PC) with 0.5 mol/L lithium perchlorate (LiClO4) medium in the presence of elaborated thin films of cerium dioxide pure and doped with manganese at varying percentages Ce1–xMnxO2 (x=0 wt%, 2 wt%, 4 wt% and 6 wt%) were successfully deposited by the spray pyrolysis (SP) technique on the glass substrate and ITO at 450 °C.The effects of manganese (Mn) doping thin films Ce1–xMnxO2 were studied and investigated by using different analyses namely X-ray diffraction (XRD) analysis, Raman spectroscopy method, UV-Vis spectrophotometer technique, atomic force microscopy (AFM) analysis and electrochemical properties. XRD data obtained present a polycrystalline with a face-centred cubic structure of fluorite type. Raman results of thin films undoped and Mn doped show two peaks at 465 and 600 cm–1, this letter due to the formation of extrinsic oxygen vacancies by the incorporation of Mn rate into Ce1–xMnxO2 matrix. Energy dispersive spectroscopy (EDS) data show the presence of Ce, O, and Mn elements in the elaborated films. The AFM results reveal that the surface roughness decreases with increasing Mn rate. Further, band gap energy of thin films decreases with increasing in Mn rate due to the formation of defect state between valence and conduction band. The storage capacity of the elaborated (Ce1–xMnxO2/ITO/PC+LiClO4) electrode reaches a maximum of 1.997 mF in the presence of 6% of Mn.

Raman spectroscopy is commonly used to estimate peak temperatures in rocks containing organic carbon. In geological settings such as fold-thrust belts, temperature constraints are particularly important as complex burial and exhumation histories cannot easily be modelled. Many authors have developed equations to determine peak tempertaures from Raman spectral parameters, most recently to temperatures as low as 75 °C. However, recent work has shown that Raman spectra can be affected by strain as well as temperature. Fold-thrust systems are often highly deformed on multiple scales, with deformation characterised by faults and shear zones, and therefore temperatures derived from Raman spectra in these settings may be erroneous. In this study, we investigate how the four most common Raman spectral parameters and ratios change through a thrust-stacked carbonate sequence. By comparing samples from relatively low-strain localities to those on thrust planes and in shear zones, we show maximum differences of 0.16 for I[d]/I[g] and 0.11 for R2, while FWHM[d] and Raman Band Separation show no significant change between low and high strained samples. Plausible frictional heating temperatures of faulted samples suggest that the observed changes in Raman spectra are not the result of frictional heating. We apply three equations used to derive the peak temperatures from Raman spectra to our data to investigate the implications on predicted temperatures between strained and unstrained samples. All three equations produce different temperature gradients with depth in unstrained samples. We observe that individual equations exhibit apparently varying sensitivities to strain, but calculated temperatures can be up to 140 °C different for adjacent strained and unstrained samples using the same temperature equation. These results have implications for how temperatures are determined in strained rock samples from Raman spectra.

As an endeavor to trace the origin of the active surface sites on La2Ce2O7 compound for OCM reaction, a dissection strategy is adopted in this work. In detail, the reaction performance of pure La2O3, CeO2, the physical mixture of La2O3 and CeO2 (La2O3+CeO2), and the combination of pure La2O3 and CeO2 with different orders in the reactor (La2O3-CeO2 or CeO2-La2O3) has been tested for OCM reaction under the same condition. Individual La2O3, CeO2 and their simple mixing/combination display much lower OCM performance than La2Ce2O7 compound, especially below 700 oC. Therefore, the reaction performance of La2Ce2O7 is not due to a simple accumulation of the two pure oxides. To achieve favorable OCM performance, La and Ce cations must be combined into a stable La2Ce2O7 compound possessing a disordered defective cubic fluorite structure with intrinsic oxygen vacancies. In situ Raman, CO2-TPD, EPR and XPS results have demonstrated on the surface of La2Ce2O7, much larger amount of both O2- species and moderate basic sites have been formed in comparison with the individual metal oxides or their simple mixing/combination, thus it exhibits the optimum reaction performance among all the catalysts.

A tailored chitosan crosslinked isovanillin (CCIV) polymeric adsorbent generated using homogeneous catalysis was applied for the extraction and removal of direct yellow dye 50 (DY 50), through rapid adsorption due to an electrostatic attraction between the dye molecules and CCIV frameworks. The removal efficiency of DY 50 was systematically investigated to determine the effect of contact time, incubation temperature, pH of the solution, initial dye concentration, and adsorbent mass. The adsorbent also appeared to exert a novel tribocatalytic energy effect for dye decompositions, which is confirmed through comparison of removal from agitation (friction) which is thought to promote the generation of reactive oxygen species. The DY 50 adsorption was almost instantaneous, where up to 83.3% of the initial DY 50 load was removed within and up to 10 min, and then to 90–97.9% by physicochemical adsorption after 45–180 min using 0.05 g of CCIV bio sorbents under ambient temperature. The variations of DY 50 initial concentrations, contact time, and temperatures allowed us to implement three isotherm models, kinetics, and thermal dynamic studies. The comparison of adsorption equilibrium data of DY 50 on the CCIV surfaces was obtained from Langmuir, Freundlich, and Temkin isotherms models, indicating the “monomer to bilayer” is favorable through van der Waals interaction. Validation of the kinetic models was obtained through the ratio of 95% and 5% extraction time (t95/t5 = 19.42) and residual sum of squares (RSS

The pixel size of the Infrared Atmospheric Sounding Interferometer (IASI) remote sensor is much smaller than the horizontal grid size of current Chemical Transport Models (CTMs). In order to assimilate the maximum of information from the IASI retrievals, we have increased the horizontal resolution of our model MOCAGE to be consistent with the IASI pixel size. Experiments are carried out with the Valentina data assimilation system using the standard and the high resolution versions of the model. Two resolutions of the horizontal Gaussian grid have been used for the model: with a T42 and a T170 triangular truncations. Our study is based on the combination of data from the IASI instrument and from the Microwave Limb Sounder (MLS), since this latter dataset allows the information to be spread through the whole atmospheric columns at a low computational cost. Two datasets of ozone super-observations have been constructed by averaging the IASI data on the two model grids. Direct model simulations without data assimilation first show that the increase of the horizontal resolution modifies the ozone smallest scale structures as well as the ozone meridional distribution. This modification results from a better representation of the vertical velocity with the T170 configuration. When the ozone assimilation is performed there is less influence of the horizontal resolution of the model. Nevertheless, in a general way, comparisons with independent data show large reductions of the ozone standard deviations when the resolution is increased. When the ozone assimilation is performed with the high resolution dataset, the high resolution model does not improve the ozone analysis compared to the one obtained with the same model resolution but with the low resolution IASI dataset. This result is due to the difficulty to combine IASI data and MLS data. For assimilating IASI data at high resolution the horizontal correlation length-scale has to be decreased to catch the small scale structures present in the dataset. By doing so the influence of the coarser resolution MLS data is decreased and part of the information brought on the vertical shape of the ozone profile is lost. It is concluded that it is essential to add information on the vertical distribution of ozone column when the IASI data is assimilated at a resolution close to the pixel size. Using IASI averaging kernels would likely improve the simulations, but the computational cost would be much higher. Alternatively, better results might be obtained by a careful tuning of the horizontal correlation length-scale.

This study explores our ability to simulate the atmospheric chemistry stemming from isoprene emissions in pristine and polluted regions of the Amazon basin. We confront two atmospheric chemistry models – a global, Eulerian chemistry-climate model (UM-UKCA) and a trajectory-based Lagrangian model (CiTTyCAT) – with recent airborne measurements of atmospheric composition above the Amazon made during the SAMBBA campaign of 2012. The simulations with the two models prove relatively insensitive to the chemical mechanism employed; we explore one based on the Mainz Isoprene Mechanism, and an updated one that includes changes to the chemistry of first generation isoprene nitrates (ISON) and the regeneration of hydroxyl radicals via the formation of hydroperoxy-aldehydes (HPALDS) from hydroperoxy radicals (ISO2). In the Lagrangian model, the impact of increasing the spatial resolution of trace gas emissions employed from 3.75° × 2.5° to 0.1° × 0.1° varies from one flight to another, and from one chemical species to another. What consistently proves highly influential on our simulations, however, is the model framework itself – how the treatment of transport, and consequently mixing, differs between the two models. The lack of explicit mixing in the Lagrangian model yields variability in atmospheric composition more reminiscent of that exhibited by the measurements. In contrast, the combination of explicit (and implicit) mixing in the Eulerian model removes much of this variability but yields better agreement with the measurements overall. We therefore explore a simple treatment of mixing in the Lagrangian model that, drawing on output from the Eulerian model, offers a compromise between the two models. We use this Lagrangian/Eulerian combination, in addition to the separate Eulerian and Lagrangian models, to simulate ozone at a site in the boundary layer downwind of Manaus, Brazil. The Lagrangian/Eulerian combination predicts a value for an AOT40-like accumulated exposure metric of around 1000 ppbv h, compared to just 20 ppbv h with the Eulerian model. The model framework therefore has considerable bearing on our understanding of the frequency at which, and the duration for which, the rainforest is exposed to damaging ground-level ozone concentrations.

The work is dedicated to a research into the physicochemical aspects of carbon nanopowder production from the gas phase by the pyrolysis of the initial precursors in a cyclic adiabatic process in a flow-through chemical compression reactor (CCR). The method allows the production of carbon nanomaterials, such as the carbon nanoparticles and globular soot particles, as well, as the core-shell structures representing the 4–7 nm composite particles with a SiC crystal core covered with graphene layers. Products have controlled and reproducible properties, and output capacity of the method is sufficient for technological purposes. The nanopowders are characterized by high-resolution transmission electron (TEM) and scanning electron (SEM) microscopy, X-ray diffraction analysis and Raman spectroscopy. The nanomaterials were used to manufacture their aqueous suspensions - nanofluids, which have shown their effectiveness in enhancing oil recovery in oil displacement technologies.

Introduction: Cannabidiol (CBD), cannabinol (CBN), and Δ9-tetrahydrocannabinol (Δ9-THC) are major cannabinoids in cannabis resin and products. The kinetic of the chemical reaction of resin cannabis is important for product development and storage. A few reports are available in the literature on the rate of CBD and Δ9-THC degradation, and CBN formation in dried resin and solutions of various pH. Materials and Methods: Thermal degradation of CBD, Δ9-THC, and formation of CBN was studied at 50°C, 60°C, 70°C, and 80°C for dried cannabis resin. The effect of pH and temperature on cannabinoids transformation in cannabis solution was also examined at pH 2, 4, 6, 8, 10, and 12 and at 40°C, 50°C, 60°C, and 70°C. High-performance chromatography coupled with diode-array detection (HPLC-DAD) was used for the analysis of CBD, CBN, and Δ9-THC transformation. The values of activation energies (Ea), shelf-life (t90% - t110%), and rate constant (k) were calculated for the CBD, Δ9-THC, and CBN. The effect of temperature and pH on the dried cannabis resin was adequately modeled with the Arrhenius equation. Results: The results indicated that the chemical kinetics in the thermal degradation of CBD, Δ9-THC, and formation of CBN were the zero-order, pseudo-zero-order, and first-order reactions, respectively, in cannabis resin. The first-order and pseudo-first-order degradation kinetics were evidenced for CBD and Δ9-THC, respectively, in cannabis solutions, whereas the zero-order formation kinetic was detected for the CBN. The transformation rate of the CBD, CBN, and Δ9-THC increased with increasing temperature, especially as temperature increased to 70°C at pH 2.0. The optimum pH for CBD stability was between pH 4 and 6, whereas the optimum pH for Δ9-THC stability was between pH 4 and 12. Conclusion: The major cannabinoids (CBD, CBN, and Δ9-THC) reacted more quickly at high temperature and in an acidic solution. Especially, the minimum transformation of CBD, CBN, and Δ9-THC was achieved by using on a low temperature, slightly to moderately acidic pH values, and short-time processing. These results may help to improve the storage condition of CBD, CBN, and Δ9-THC products and in the manufacturing process.

In the study, the layered double hydroxide (LDH) of NiZnFe and its composites with date-palm biochar (LDH-DPb) and carbon nanotubes (LDH-cnt) were synthesized for adsorbing reactive black 5 (RB5) dye from aqueous solutions. In the first 5 min, rapid adsorption was followed by a gradual increase in both dye uptake and removal efficiency of up to 60 min of starting time. In the investigated pH range (3.0–8.0), the removal efficiency linearly decreased while the sorption capacity linearly increased for all three adsorbents as their doses increased to 0.3 or 0.4 g following a decreasing trend up to 0.6 g. By increasing the initial RB5 concentration from 10 to 100 mg L−1, the removal efficiency linearly decreased. A nearly perfect fitting of the pseudo-second-order kinetic model to the adsorption data was observed; however, the Elovich kinetic model showed the heterogeneous surface of adsorbents with chemisorption. At the solid–liquid interface, from a thermodynamics point of view, we obtained the nonspontaneous nature of the adsorption of RB5 dye of the studied adsorbents with an increased disorder, which supported the endothermic nature onto the studied adsorption process. Furthermore, a nearly perfect fitting of the Langmuir model was obtained to the adsorption data, thereby suggesting the monolayer adsorption of RB5 dye onto the studied adsorbents. In the Dubinin–Radushkevich model, a good agreement of the calculated adsorption capacities to the experimental values were observed and the chemical adsorption of RB5 dye on to the studied adsorbents was proposed based on E (8 – 16 kJ mol−1).

Calix [4] arene refers to a group of large cyclic compounds involving a sequence of phenols, which are obtained through the hydroxylation reaction process of phenol and aldehyde derivatives. Calixarenes have a rigid and three-dimensional structure. Nanoparticles can be used in drug delivery due to their ability to enter cells. The application of a carrier for drug delivery is very effective on improving their performance. In order to employ calixarene nanoparticles as the carriers of mercaptopurine drug, their ability and type of adsorption were examined on laboratory scale. In this study, by examining the temperature changes on the course of adsorption and by matching the data against Langmuir adsorption isotherm, Freundlich, and Dubin Radushkovich, the numbers of all thermodynamic constants of this process were calculated. The obtained adsorption capacities indicated that the elevation of the initial concentration leads to the enhanced adsorption capacity. Moreover, by considering the obtained thermodynamic constants, it was found that the adsorption process is exothermic, while the values of Gibbs free energy ∆G0 and the adsorption energy Ea showed that the adsorption process was spontaneous and chemical.

The classical Hantzsch reaction is a simple and utmost efficient protocol for the synthesis of biologically and pharmacologically important 1,4-dihydropyridine derivatives. The present study deals with the utilization of modified heteropoly acid (HPA) catalysts (5 wt% WOx-FeP and 5 wt% MoOx-FeP) in the synthesis of novel Hantzsch 1,4-dihydropyridines, which contains diphenylsulfone moiety via one-pot synthesis strategy under ultrasound irradiation. The developed protocol is simple and green procedure for the synthesis of 1,4-dihydropyridines and is applicable to synthesize different 1,4-dihydropyridine derivatives. The synthesized HPA catalysts offered a sustainable methodology to produce excellent products yields (88–92%) of 1,4-dihydropyridine derivatives. The catalysts were characterized by XRD, Raman, FT-IR, DRUV-vis, XPS, H2-TPR, N2-physisorption and acidity measurements. The HPA supported iron phosphate nanotubes (FeP) catalysts offered enhanced the catalytic performance through the improved Lewis acid site density, redox properties and surface area, compared to the parent phosphomolybdic and phosphotungstic acids. Moreover, the synthesized catalysts can be easily separated from reaction system and reused for six times efficiently without significant loss of activity.

2,4(5)-Dinitroimidazole (2,4(5)-DNI) is an important energetic material, and it is also an important precursor for the preparation of drugs and energetic materials. In this study, the solubility of 2,4(5)-DNI in eleven pure solvents (chlorobenzene, benzene, 1,2-dichloroethane, toluene, water, isopropyl alcohol, ethyl acetate, acetonitrile, methanol, 1,4-dioxane and acetone) were measured by using a dynamic test method from 278.15 K to 323.15 K under 101.1 kPa. Four solubility models were used to fit the experimental data, which were ideal model, modified Apelblat equation, polynomial empirical equation, and λh equation. Meanwhile, the relative average deviation and root-mean-square deviation between the experimental data and the fitted data were also calculated. Furthermore, the three thermodynamic parameters, i.e., dissolution enthalpy, dissolution entropy and Gibbs energy were obtained based on solubility data. Finally, the crude product of 2,4(5)-DNI was crystallized with acetone as solvent, and the purity of the crystalline product was greater than 99.5%.

This work aims to evaluate the dynamic performance of a highly selective Ni-based surface during the oxidative dehydrogenation of ethane (ODH-C2). The catalyst comprises an in-house bimetallic mixed-oxide formulation with a Ni/Sn atomic ratio of 10. To corroborate its proper synthesis, it is characterized by TGA, AES, XRD, physisorption of N2 and TEM. The catalytic evaluation of the mixed oxide under dynamic conditions allows the proposition of a redox surface mechanism whose reliability is evaluated through a rigorous analysis, which is based on the development of a kinetic model and a robust experimentation program using a fully-automated micro-reaction unit and registering in-situ surface temperatures and continuous inline monitoring of oxygen and carbon dioxide. Experiments are carried out using a mixture of ethane or ethylene, oxygen and nitrogen as feedstock, at temperatures from 360 to 480 °C, total pressures from 100 to 500 kPa, and space-time values from 8.1 to 133.1 kgcat s molC2H6−1. Oxygen conversion ranges from 5% to 100% while the one for ethane varies from 5% to 60%. Besides, the selectivity and yield to ethylene vary from 30% to 90% and from 2% to 40%, respectively. The suitability of the redox mechanism is here assessed by evaluating statistical and phenomenological foundations, including Boudart’s criteria. Kinetic parameters, estimated by non-linear regression and using the reparametrized form of the Arrhenius and van’t Hoff equations, are phenomenologically well founded, such that changes of entropy and enthalpy of adsorption correctly describe the loss of mobility due to adsorption and the exothermic nature of the adsorption processes. Ethylene formation is the reaction demanding the lowest activation energy (Ea1 = 61.94 kJ mol−1), while the total oxidation of ethane is the path requiring the largest activation energy (Ea2 = 132.6 kJ mol−1). Concerning the adsorption enthalpy, ethylene exhibits the largest value ( − Δ H C 2 H 4 ° = 123.39 kJ mol−1), while carbon dioxide presents the lowest one ( − Δ H C O 2 ° = 42.00 kJ mol−1). Additional findings can be summarized as follows: activity and selectivity are recovered after the dynamic operation under oxidative conditions of the catalytic surface; carbon dioxide is identified as the only no desired byproduct; and hydroxyl surface species lead to the formation of water which affects the selectivity to ethylene, as well as the reaction rates. These findings are of interest for future studies directed at elucidating the performance of the Ni-based catalyst at larger scales, paving the way for the efficient design of the industrial reactor for the ODH-C2.

Rare earth elements (REE) are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention. However, the separation of REE in these alternative resources is still a challenge due to the low concentration of REE and multi coexisted ions in acidic system. In this study, the species distribution of REE within the pH 0 to 8.0 was calculated. The SBA-15 originated from coal fly ash was modified by two steps with (3-Aminopropyl) triethoxysilane (APTES) and diethylenetriaminepentaacetic dianhydride (DTPADA) to obtain DTPADA-SBA-15 adsorbent, which was applied to the selective adsorption of REE. The results showed that DTPADA-SBA-15 possessed excellent adsorption performance on the selective adsorption of REE, including Eu, Gd, Tb, Nd and Sm, in acidic solution (pH 2) with multi competing ions. The FT-IR and Zeta potential characterization verified that the chemical adsorption through the coordination of O in DTPADA-SBA-15 with REE was dominant at lower pH value. The study of adsorption kinetics indicated that the adsorption of rare earth metal ions followed pseudo-second-order kinetic, of which the adsorption process followed the Langmuir isotherm model.

Magnetite nanoparticles@Fe-BTC composite material was synthesized by a solvothermal method, where magnetite nanoparticles were added during the synthesis and was characterized by different analytical techniques analytical such as XRD, Raman and FTIR spectroscopy, and nitrogen physisorption at 77 K. Magnetite nanoparticles into Fe-BTC composite material was used in the adsorption of metals ions such as copper (Cu(II)), mercury (Hg (II)), arsenic (As (III)), and lead (Pb (II)). The experimental data of the adsorption of Cu(II), As (III), and Pb (II) metals ions showed a better fit to Langmuir isotherm model, while for the Hg (II) ion adsorption was observed a better adjusts to Temkin isotherm model. The kinetic pseudo-second-order model is the one that better describes the experimental data in all metal ions. The composite material showed a maximum adsorption capacity of 55 mg/g, 57 mg/g, 147 mg/g, and 155 mg/g for Cu (II), As (III), Pb (II), and Hg (II), respectively which was considerable. The adsorption selective for composite material in the mixed metal solution followed the order of Cu (II)> Pb (II) > Hg (II) > As (III). Therefore, composite material could be a good alternative as adsorbent material for the remediation of contaminated water by heavy metals.

In this work, thermodynamic and kinetic factors that affect formation and phase transformation process of different solid forms of levofloxacin hydrochloride were investigated in detail. Dynamic vapor sorption experiments (DVS) and varying temperature-powder X-ray diffraction (VT-PXRD) experiments were carried out to study moisture-dependent stability, thermal stability as well as the transformation process between Form I and Form II. Critical water activities of levofloxacin hydrochloride were determined in temperature range of 5.0–45.0 °C. Raman spectroscopy was applied to in situ monitor the temperature-induced phase transformation and the hydration process of levofloxacin hydrochloride, and one possible mechanism consisting of multiple chemical equilibria was proposed to analyze the effect of thermodynamic and kinetic factors on the formation and transformation of different solid forms. Results show that the anhydrate, Form II would transform to the monohydrate, Form I more easily with the increasing water content. And the transition point moves toward higher water contents as the temperature increases. The results suggested that, except for thermodynamic factors, kinetic factors also play an essential role in controlling the solid forms of polymorphic compounds.

New WFe oxides based catalysts were prepared by successive or simultaneous impregnation method on pseudo boehmite in order to understand the role of Fe and evaluate the influence of the preparation method, W loading, and partial reduction of supported species, on the oxidative desulfurization (ODS) performance of dibenzothiophene compounds (DBTs). The catalysts were characterized by SEM-EDS, N2 physisorption, TPR, XPS and Raman spectroscopy (Operando and ex-situ conditions). According to the results, the promoting effect of Fe favors the formation of hydrated WO6 species, mainly in partially reduced samples. The increase of the catalytic activity of up to 7 times using partially reduced catalysts (compared to calcined catalysts) was attributed to the presence of hydrated WO6 species. The above performance allows to achieve ultra-low sulfur content fuels (

The optical and thermal properties of a new class of fluoroindate glass with different erbium contents were investigated via Raman, transmission, and fluorescence spectroscopies, fluorescence decay curve analysis, and differential scanning calorimetry. The strength parameters of the samples were calculated using the Judd–Ofelt theory. The mid-infrared luminescence properties of erbium-doped fluoroindate glasses were studied, and a strong emission at 2.7 μm was obtained. Compared with the traditional ZBLAN glass, this glass has excellent emission properties, especially a longer fluorescence lifetime (7.09 ms) and larger emission cross-section (6.95 × 10−21 cm2) at 2.7 μm. The results indicate that fluoroindate glass is an attractive host for mid-infrared lasers and as a gain medium for optical amplifier applications.

The utilization of coal fly ash derived from circulating fluidized bed combustion (CFBFA) still faces great challenges because of its unique characteristics. In this study, a zeolitic material with Na-P1 zeolite as the main phase was successfully synthesized via a hydrothermal method by using CFBFA as the raw material. The effects of hydrothermal temperature, time, and added CTAB amount on the characterizations of synthesized materials were investigated by XRD, SEM, and XPS. The properties of the optimal zeolitic material and its adsorption performance for Pb2+ in aqueous solution were evaluated. The influences of pH, initial concentration, dosage, and temperature on Pb2+ adsorption were also examined. Results revealed the following optimal parameters for the synthesis of zeolitic material: NaOH concentration of 2 mol·L-1, solid-to-liquid ratio of 1:10 g·ml-1, hydrothermal temperature of 110 °C, hydrothermal time of 9 h, and CTAB amount of 1 g (per 100 ml solution). The adsorption capacities of the zeolitic material reached 329.67, 424.69, and 542.22 mg·g-1 when the pH values of aqueous solution were 5, 6, and 7, respectively. The Pb2+removal efficiency can reach more than 99% in aqueous solution with the initial concentrations of 100–300 mg·L-1 under pH 6 and suitable adsorbent dosage. The adsorption and kinetics of Pb2+ on the zeolitic material can be described by Langmuir isotherm and pseudo-second-order kinetic models, respectively. The ion exchange between Pb2+ and Na+ and chemisorption are the main adsorption mechanism. All these findings imply that the synthesis of low-cost adsorbent for Pb2+ removal from weak acid and neutral aqueous solution provides a highly effective method to utilize CFBFA.

The effect of gold nanoparticles supported on V2O5/TiO2 nanomaterials prepared by different routes and its activity in the CO oxidation at low temperature were studied. The catalysts were characterized by N2 physisorption, X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). This study showed that the sol-gel Au-V2O5/TiO2 material exhibited higher catalytic activity after a thermal treatment at 400 °C in hydrogen than Au-V2O5/NT nanotubes, Au-V2O5/P25 Evonik and V2O5/TiO2 nanomaterials. The sol-gel Au-V2O5/TiO2 catalyst was also more active than Au/TiO2. These results could be explained by the fact that the gold species (Au° and Au1+) improved the interaction between vanadium species and TiO2, allowing high vanadium oxidation states (from V3+ to V5+) through a charge transfer effect between the support surface and Au-VOx reactive species; the presence of monovanadate and Ti3+ species led to remarkable activity in the CO oxidation from 0 °C in comparison with Au/TiO2.

The present study proposes a segmented cooling-stream injection structure based on a certain coolant mass flow rate, and numerically investigates the effect of segmented cooling-stream injection on supersonic film cooling. The results indicate that without shock-wave impingement and with helium as the coolant, segmented cooling-stream injection can reduce the mixing between the mainstream and the cooling stream to produce better cooling performance than single injection, especially at larger coolant Mach numbers. However, with nitrogen as the coolant, the cooling effect of the segmented-injection system is very close to that of the single-injection system. Mixing at the impinging region is enhanced significantly when there is an incident shock wave. When the shock wave impinges between the two coolant inlets, segmented cooling-stream injection improves film cooling effectiveness in the midstream and downstream regions more than single injection because only part of the cooling stream undergoes the enhanced mixing effect of the shock wave. The advantage of segmented injection is reduced when the impinging region is behind the second coolant inlet. The further downstream the impinging region, the smaller the associated advantage.

Owing to the exorbitant overpotential and serious carrier recombination of graphitic carbon nitride (g-C3N4), noble metal (NM) is usually served as the H2 evolution co-catalyst. Although the NM (such as Pt) nanoparticles can reduce the H2 evolution overpotential, the weak Van der Waals interaction between Pt and g-C3N4 makes against the charge transfer. Herein, the solvothermal method is developed to achieve semi-chemical interaction between Pt and g-C3N4 nanotube (Pt-CNNT) for fast charge transfer. Moreover, the generated in-plane homojunction of CNNT can accelerate charge separation and restrain recombination. Meanwhile, the metallic Pt is an excellent H2 evolution co-catalyst. Photo/electrochemical tests verify that the semi-chemical interaction can improve photogenerated charge separation and transferability of CNNT. As a result, the photocatalytic H2 evolution turnover frequency (TOF) of Pt-CNNT under visible light irradiation reaches up to 918 h−1, which is one of the highest in the g-C3N4-based photocatalysts. This work provides a new idea to improve the charge transfer for efficient photocatalytic H2 evolution.

To enable chemical speciation, monitoring networks collect particulate matter (PM) on different filter media, each subjected to one or more analytical techniques to quantify PM composition present in the atmosphere. In this work, we propose an alternate approach that uses one filter type (teflon or polytetrafluoroethylene, PTFE, commonly used for aerosol sampling) and one analytical method, Fourier transform infrared (FT-IR) spectroscopy to measure almost all of the major constituents in the aerosol. In the proposed method, measurements using the typical multi-filter, multi-analytical techniques are retained at a limited number of sites and used as calibration standards. At all remaining sites, only sampling on PTFE and analysis by FT-IR is performed. This method takes advantage of the sensitivity of the mid-IR domain to various organic and inorganic functional groups and offers a fast and inexpensive way of exploring sample composition. As a proof of concept, multiple years of samples collected within the Interagency Monitoring of PROtected Visual Environment network (IMPROVE) are explored with the aim of retaining high quality predictions for a broad range of atmospheric compounds including mass, organic (OC), elemental (EC), and total (TC) carbon, sulfate, nitrate, and crustal elements. Findings suggest that models based on only 21 sites, covering spatial and seasonal trends in atmospheric composition, are stable over a 3 year period within the IMPROVE network with acceptable prediction accuracy (R2 > 0.9, median bias less than 3 %) for most constituents. The major limitation is measuring nitrate as it is known to volatilize off of PTFE filters. Incorporating additional sites at low cost, partially replacing existing, more time- and cost-intensive techniques, or using the FT-IR data for quality control or substitute for missing data, are among the potential benefits of the one-filter, one-method approach.

Background: High methionine-diet (HMD) causes Alzheimer's disease (AD)-like symptoms. Previous studies have shown that Dendrobium nobile Lindle. alkaloids (DNLA) had potential benefits for AD. Object: Whether DNLA can improve AD-like symptoms induced by HMD is to be explored. Method: Mice were fed with 2% HMD diet for 11 weeks, the DNLA20 control group (20 mg/kg), DNLA10 group (10 mg/kg), and DNLA20 group (20 mg/kg) were administrated with DNLA for 3 months. Morris water maze test was used to detect learning and memory ability. Neuron damage was evaluated by HE and Nissl stainings. Levels of homocysteine (Hcy), beta-amyloid 1-42 (Aβ1-42), S-adenosine methionine (SAM), and S-adenosine homocysteine (SAH) were detected by ELISA. Immunofluorescence and western blotting (WB) were used to determine the expression of proteins. CPG island methylation. Results: Morris water maze test revealed that DNLA improved learning and memory dysfunction. HE, Nissl, and immunofluorescence stainings showed that DNLA alleviated neuron damage and reduced the 5-methylcytosine (5-mC), Aβ1-40, and Aβ1-42 levels. DNLA also decreased the levels of Hcy and Aβ1-42 in the serum, along with decreased SAM/SAH levels in the liver tissue. WB results showed that DNLA down-regulated the expression of the amyloid-precursor protein (APP), presenilin-1 (PS1), beta-secretase-1 (BACE1), DNA methyltransferase1 (DNMT1), Aβ1-40, and Aβ1-42 proteins. DNLA also up-regulated the expression of the protein of insulin-degrading enzyme (IDE), neprilysin (NEP), DNMT3a, and DNMT3b. Meanwhile, DNLA increased CPG island methylation levels of APP and BACE1 genes. Conclusions: DNLA alleviated AD-like symptoms induced by HMD via the DNA methylation pathway.

The properties of two-dimensional (2D) materials are highly dependent on their phase and thickness. Various phases exist in tin disulfide (SnS2), resulting in promising electronic and optical properties. Hence, accurately identifying the phase and thickness of SnS2 nanosheets is prior to their optoelectronic applications. Herein, layered 2H-SnS2 and 4H-SnS2 crystals were grown by chemical vapor transportation and the crystalline phase of SnS2 was characterized by X-ray diffraction, ultralow frequency (ULF) Raman spectroscopy and high-resolution transmission electron microscope. As-grown crystals were mechanically exfoliated to single- and few-layer nanosheets, which were investigated by optical microscopy, atomic force microscopy and ULF Raman spectroscopy. Although the 2H-SnS2 and 4H-SnS2 nanosheets have similar optical contrast on SiO2/Si substrates, their ULF Raman spectra obviously show different shear and breathing modes, which are highly dependent on their phases and thicknesses. Interestingly, the SnS2 nanosheets have shown phase-dependent electrical properties. The 4H-SnS2 nanosheet shows a current on/off ratio of 2.58 × 105 and excellent photosensitivity, which are much higher than those of the 2H-SnS2 nanosheet. Our work not only offers an accurate method for identifying single- and few-layer SnS2 nanosheets with different phases, but also paves the way for the application of SnS2 nanosheets in high-performance optoelectronic devices.

Embargado hasta 31/01/2024 In this work, photocatalysts consisting of TiO2 supported on zeolite (USY62) were synthesized by sol-gel method and, subsequently, a noble metal (Pt, Au, or Ag) was incorporated by impregnation or photodeposition. Zeolite-TiO2 composites were characterized by SEM, TEM, XRD, N2 adsorption-desorption, Raman and UV–vis spectroscopy, and well-dispersed anatase TiO2 particles (ca. 10 nm) that exhibited a blue-shift in the UV–vis absorption due to the size quantization effect were produced. The photocatalytic activity of all zeolite-TiO2 composites was examined by the photoreforming of aqueous glycerol solution (10% w/w) under UV and solar-simulated radiation. The activity of the zeolitic photocatalysts decreased in the order Pt > Au > Ag, being catalysts prepared by photodeposition more active than those prepared by impregnation. Moreover, Zeolite-supported TiO2, led to a TiO2 with smaller deactivation in H2 production than unsupported TiO2, which can be ascribed to the small TiO2 particle size or an interaction zeolite-TiO2. All in all, a photocatalyst (USY-Ti-PPt) with TiO2 up to four times more active than unsupported TiO2 under UV radiation was prepared.

Molybdenum trioxide (MoO3) can be employed as an excellent host for intercalation due to its 2D layered structure that connected by van der Waals interactions. Herein, a series of polyoxometalate-based MoO3 composites (Al13@MoO3) were successfully prepared by interpolating the Keggin-type polycationic AlO4Al12(OH)24(H2O)127+ (Al13) into MoO3 gallery. These composites can be applied to rapidly adsorb the anionic dye methyl orange (MO) through strong electrostatic interactions lead to compact and stable gathering in the surrounding of the numerous charged Al13. Adsorption behaviors of composites with the different amount of Al13 were determined, these results revealed that Al13-3.34%@MoO3 exhibited the most remarkable adsorption capacity. More importantly, the composite maintains superior adsorption capacity for five consecutive adsorption/desorption cycles, suggesting that Al13@MoO3 can be an efficient and durable adsorbent.

Studies on the degradation process of waste polyethylene terephthalate (PET) have become increasingly mature, but there are relatively few studies on the separation of degradation products. The products contain many components and the separation of which is difficult. Therefore, the study on phase equilibrium thermodynamics of bis-2-hydroxyethyl terephthalate (BHET) is of great theoretical significance and practical value to provide basic data for the BHET crystallization separation. In this work, the degraded products were purified and characterized. The solubility of BHET in methanol, ethanol, ethylene glycol, water and the mixture of ethylene glycol+water were determined by static method. The experimental results were correlated with different models, such as IS model, λh equation, Apelblat equation and NRTL model. Based on the Van't Hoff equation, the mixing Gibbs energy, enthalpy and entropy were calculated. From this work, the basic data which can be used to guide the crystallization process of BHET were obtained, including solubility data, correlation model and thermodynamic properties

As a two-dimensional carbon based semiconductor, C3N acts as a promising material in many application areas. However, the basic physical properties such as Raman spectrum properties of C3N is still not clear. In this paper, we clarify the Raman spectrum properties of multilayer C3N. Moreover, the stacking driven Raman spectra change of multilayer C3N is also discussed.

The mechanism of syngas to ethanol on MoCu(211) surface has been researched by density functional theory (DFT) calculation, and the effects of Mo as a promoter on C−O bond breaking and C−C bond formation have been discussed. Calculations show that Cu-Mo atoms constitute the active sites on MoCu(211) surface after Mo atom being served as a promoter of Cu catalyst. Compared with Cu(211), MoCu(211) has two improvements. Firstly, CH3 is the most advantageous monomer on the MoCu(211) surface, which provides abundant CH3 intermediate for syngas to ethanol. Secondly, the C−C bond is formed mainly by inserting CHO into the abundant CH3, and the generated CH3CHO through multiple steps of hydrogenation to generate C2H5OH. The key of the promoter Mo on the MoCu(211) surface also has been verified by the analysis of its electronic properties. Differential charge density shows that the massive electron transfer from Mo to Cu, projected density of states (pDOS) shows that the electron transfer from Mo to Cu makes the d-band center of MoCu(211) nearer to the Fermi level, these indicate that the MoCu(211) catalytic capacity increased. The addition of Mo in the Cu-based catalyst not only can effectively solve the problem of C−O bond breaking, but also promote C−C bond formation. About the influence of Mo content on C−O bond breaking and C−C bond formation, compared with MoCu(211), the DFT results and the d-band center of Mo2Cu(211) show that the increase of Mo content could not promote the synergistic effect of Cu/Mo on the generation of ethanol more effectively.

Tandem repeats in genomic sequences are characterized by two or more contiguous copies of a pattern of nucleotides. The role of these repeats as molecular markers is well established in various genetic disorders, human evolution studies, DNA forensics and intron retention. In this work a computational method has been developed for the extraction of both exact and approximate tandem repeats. The proposed algorithm uses Ramanujan Fourier Transform (RFT) to identify periodicities in the DNA sequences. Since RFT estimates the period directly, rather than inferring it from the signal's spectrum, it provides a more sensitive and rapid detection of tandem repeats as compared to other available popular computational methods.

The dye laser analysis depends on the gain equation that contains cross sections of the relevant emission and absorption molecular transitions involved in the lasing process. The absorption cross-section σs (v) is directly related to the absorbance curves of the dye. The emission cross-section σem (v) has been derived in terms of directly measurable spectroscopic quantities. The low frequency tail of the absorption curves is minutely diminishing for very dilute solutions(~=10-5 mole/lit) usually used in laser system. This low frequency tail overlaps the operating frequency band of the laser. The linear dependence of the dye absorption on the dye concentration (Beer- Lambert law), is used to solve the low frequency tail problem. The intrinsic gain characteristics are calculated for the dye Rhodamine "B" and the results are in good agreement with the rep orted experimental results.

Two Bi–Mo–Co–Fe–O catalysts were synthesized by flame spray pyrolysis and tested for their catalytic performance in selective oxidation of propylene to acrolein. Pronounced structural changes during temperature–programmed oxidation and reaction were observed by operando X–ray absorption spectroscopy, X–ray diffraction, Raman spectroscopy, and thermogravimetric analysis. During oxidative treatment, mainly binary oxide phases (α–Bi$^{2}$Mo$^{3}$O$^{12}$, β–CoMoO$^{4}$, Fe$^{2}$ (MoO$^{4}$)$^{3}$) were observed, but single (MoO$^{3}$) or ternary (Bi$^{3}$ (FeO$^{4}$)(MoO$^{4}$)$^{2}$) oxides also formed depending on the relative elemental catalyst composition. During propylene oxidation, the reduction of Fe$^{3+}$ to Fe$^{2+}$ led to a strong rise in activity and induced further phase transformations. MoO$^{3}$ was found to be unselective towards acrolein but was essential in binding other single oxides. The formation of β–Co$^{0.7}$Fe$^{0.3}$MoO$^{4}$ and Bi$^{3}$ (FeO$^{4}$)(MoO$^{4}$)$^{2}$ as well as their synergistic interplay with α–Bi$^{2}$Mo$^{3}$O$^{12}$ are key factors for high performance. The combination of complementary operando methods was crucial to reveal new structure–activity/selectivity correlations, therefore bridging the knowledge gap between simplified model systems and complex applied catalysts.

The formation of solid electrolyte interphase (SEI) and ion intercalation are two key processes in rechargeable batteries, which need to be explored under dynamic operating conditions. In this work, both planar and sandwich model lithium batteries consisting of Li metal | ionic liquid electrolyte | graphite electrode have been constructed and investigated by a series of in situ surface analysis platforms including atomic force microscopy, Raman and X-ray photoelectron spectroscopy. It is found that the choice of electrolyte, including the concentration and contents, has a profound effect on the SEI formation and evolution, and the subsequent ion intercalation. A smooth and compact SEI is preferably produced in high-concentration electrolytes, with FSI- salt superior to TFSI- salt, facilitating the lithiation/delithiation to achieve high capacity and excellent cycle stability, while suppressing the co-intercalation of electrolyte solvent ions. The innovative research scenario of well-defined model batteries in combination with multiple genuinely in situ surface analysis methods presented herein leads to insightful results, which provide valuable strategies for the rational design and optimization of practical batteries, and energy storage devices in general.

Salidroside (8-O-β- d -glucoside of tyrosol), a plant-derived natural product, is used for treatment of hypoxia, fatigue and aging diseases. The availability of salidroside is restricted since it is extracted from 3-5 years old Rhodiola roots, which grow very slowly in the cold region of northern hemisphere of Earth. Our laboratory has constructed an engineered Escherichia coli and established a fermentation process to produce salidroside from glucose. In this article, nine macroporous resins from polarity to non-polarity, including NKA-9, S-8, AB-8, SP825, D101, LSA-8, LX-12, LX-18 and LX-68 resins, were tested to separate salidroside from fermentation broth. After static and dynamic experiments, the weakly polar SP825 resin had a better separation efficiency among nine resins. The adsorption kinetic and isotherm of salidroside on the SP825 resin were determined, and the pseudo-second-order kinetic model and Langmuir model could be fitted well. The effects of the pH on adsorption and ethanol concentration on desorption were investigated, and an optimal separation process was established. The adsorption for salidroside in the SP825 resin column was conducted with loading 150 ml at pH 7, and desorpted by washing 50 ml of 80% ethanol solution. Under the best process conditions, the purity and yield of salidroside in the final product were 91.6% and 74.0%, respectively. The results showed that the macroporous SP825 resin would be feasible and effective to prepare salidroside and has promising application in the downstream process of microbial fermentation. © 2020 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd.. All rights reserved.

Adsorbents with simple preparation and high surface area have become increasingly prevalent for the removal of organic contaminants. Herein, a carbon nanoplate codoped by Co and N elements with abundant ordered mesoporous (Co/N-MCs) was applied as an adsorbent for tetracycline removal. Taking integrated advantages of ordered mesopores on carbon-based structures and N-doping inducing the strengthened π–π dispersion and generation of pyridinic N, as well as cobaltic nanoparticles embedded in carbon nanoplates, the Co/N-MCs was tailored for high efficiently absorbing tetracycline via π-π interaction, Lewis acid-base interaction, metal complexation and electrostatic attraction. The Co/N-MCs had the advantages of high surface area, porous structure, plenty adsorption sites, and easy separation. As such, the as-prepared Co/N-MCs adsorbents significantly enhanced tetracycline removal performance with a maximum adsorption capacity of 344.83 mg·g-1 at pH 6 and good reusability, which was finally applied to removal tetracycline from tap water sample. Furthermore, the adsorption process towards tetracycline hydrochloride could be well attributed to the pseudo-second-order kinetic and Langmuir isotherm models. Compared with traditional carbon-based adsorbents, it owns a simpler synthesis method and a higher adsorption capacity, as well as it is a promising candidate for water purification.

In this study, europium (Eu) was precipitated in TiO2 powder using liquid phase plasma (LPP) process to prepare a photocatalyst with higher activity, even in the visible light range. Eu was uniformly deposited on the surface of TiO2 by the LPP method. It was observed that the amount of Eu precipitated on the TiO2 surface increased with increasing precursor concentration. XPS and EDS analysis showed that Eu was precipitated as europium oxide. The precipitation of Eu shifted the position of the Raman peak to a higher wavelength; with higher Eu content, the band gap energy decreased. Particularly, the photocatalytic efficiency of the Eu doped TiO2 photocatalyst (EDTP) in the visible light source was much higher than that of bare TiO2, and with higher Eu content, the photocatalytic activity was improved. Acetylsalicylic acid was attacked by HO∙ produced on the EDTP’s surface and assumed to be finally mineralized to H2O and CO2 via two decomposition pathways, namely, decarboxylation and deacetylation.

In this study, Ag0.23/(S1.66-N1.91/TiO2-x) single-atom photocatalyst was synthesized by in-situ photo-reducing of silver on S,N-TiO2-x nanocomposite and used to degrade bisphenol A (BPA) through heterogeneous activation of potassium peroxymonosulfate (PMS) under visible-light illumination. The structure, physicochemical property, morphology, and electronic property were evalutated by X-ray diffraction (XRD), Raman spectrum, X-ray photoelectron spectra (XPS), high-resolution transmission electron microscopy (HR-TEM), UV–vis diffuse reflectance spectra (UV-vis DRS), electron paramagnetic resonance (EPR) spectrum. Ag0.23/(S1.66-N1.91/TiO2-x) single-atom photocatalyst exhibited 2.4 times higher activity for the synergetic degradation of BPA than that of its counterpart, and 48.73% mineralization rate of BPA also achieved. It was ascribed to the uniformly-dispersed metallic Ag atoms as the active site for accelerating the migration rate of photo-generated carrier for generation of high reactive radicals. The EPR experiments indicated that SO4•‒ and •OH was jointly involved in BPA degradation.