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关键词： Tunlan coal   Molecular structure   Physicochemical structure model   Nanopore   Microcrystalline structure  

摘要： Physicochemical structure is essential for understanding physiochemical properties of coal reservoir and coalbed methane (CBM) occurrence. In this work, ultimate analysis, C-13 nuclear magnetic resonance spectra (NMR), Fourier transform infrared spectroscopy (FTIR) and gas chromatograph/mass spectrometer (GC/MS) tests were adopt to investigate the coal molecular structure information. Then, by means of molecular simulation, stable three-dimensional (3D) molecular structure and physicochemical structure models of Tunlan coal were established to reveal the physicochemical response at a molecular level. Results show that compared with the single molecular structure, angle and torsion energies in nanopore structure play a more important role in maintaining a stable and stereoscopic structure. While the electrostatic energy in non-bond energy can simulate to form nanopore space in coal. Then, with the dissolution of low molecular weight compounds (LMWCs), the pore volume (PV) of micropores increases gradually, while the corresponding specific surface area (SSA) decreases first and then increases, suggesting that pore expansion and pore increase effects are dominant in the early and the later dissolution stages, respectively. Furthermore, observing physicochemical response, total pore structure distribution depends on whether vertical or horizontal changes of basic structure units in coal make a great contribution in this evolution stage. Actually, when the aromatic layer is mainly the increase of the stacking height L-c, it is easy to result in the decrease of total SSA and PV. In contrast, for mainly the increase of the diameter L-a, all pores in coal present an increase characteristic to induce the increase of total SSA and PV.

关键词： Cucumbers   Fertilizers   Physicochemical properties   Chemical elements   Volatiles  

摘要： The main purpose of the present study was to investigate the effect of different fertilizers on the physicochemical properties, multi-element and volatile composition of cucumbers. All samples were divided into five groups according to different combinations and amounts of chicken manure, NPK 17-17-17 fertilizer and microbial fertilizer. The co-application of chicken manure (120,000 kg/ha) and NPK 17-17-17 fertilizer (750 kg/ha) achieved the best texture properties, whereas the addition of the microbial fertilizer at 6000 kg/ha significantly improved the color quality of cucumbers. Similarly, the co-application of chicken manure, NPK 17-17-17 fertilizer and microbial fertilizer at 6000 kg/ha enhanced the number and abundance of volatile components detected in the cucumbers. Cucumbers from the control group contained the highest levels of most of the determined elements. Overall, a combination of chicken manure, NPK 17-17-17 fertilizer and 6000 kg/ha microbial fertilizer is recommended as a relatively efficient fertilizer utilization for cucumbers.

关键词： Physical chemistry   Biomaterials   Two dimensional materials   Vinyl   Spectroscopy  

关键词： Physicochemical properties  

摘要： Microbial flora of probiotic yogurt can have nutraceutical properties and improve beneficial health effects of food products. In this study, microbial and physicochemical properties of raw chicken fillets dipped in regular yogurt and probiotic yogurt containing Lactobacillus casei, preserved at 4 & DEG;C for 9 days, were studied. In this regard, microbial analysis (Staphylococcus aureus, fecal coliform, yeasts, and molds) and physicochemical analysis (pH, water holding capacity, cooking loss percentage, Thiobarbituric acid reactive substances, and texture profile analysis) were performed during the storage time. In comparison with control samples, the amount of Staphylococcus aureus, fecal coliforms, yeast and mold counts, pH index, malondialdehyde value, and cooking loss percentage reduced significantly (P < 0.05) in the chicken fillets treated with regular and probiotic yogurt, while the water holding capacity increased in six days. It was concluded that probiotic and regular yogurts reduced microbial growth and improved the physicochemical quality of chicken fillets during storage and cooking time.

关键词： Differential scanning calorimetry  

摘要： The present work investigates the effects of cis and trans butenedioic acid isomers (maleic acid and fumaric acid) on the crystallinity and pharmaceutical behavior of lumefantrine. Differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), attenuated total reflectance infrared spectroscopy (ATR-IR), solid-state nuclear magnetic resonance spectroscopy (ss-NMR), and single-crystal X-ray diffraction (SC-XRD) studies were employed. Lumefantrine-fumaric acid crystallized as a salt in the monoclinic space group P2(1)/c. In comparison, DSC and PXRD showed the formation of a co-amorphous solid with maleic acid. Complete proton transfer with a strong ionic interaction led to crystalline salt formation with the trans isomer, whereas weaker/fewer hydrogen bonds with the cis isomer of butenedioic acid led to a co-amorphous salt. The in vitro dissolution of both salts resulted in a similar 2.6-2.7-fold improvement in dissolution rate when compared to that of the crystalline lumefantrine. The crystalline and co-amorphous salts were stable under accelerated stability conditions (40 +/- 2 degrees C and 75 +/- 5% RH) for one month.

关键词： Bismuth   Supramolecular   DFT   X-ray diffraction   Dithiocarbamate   Organometallic   Organolithium  

摘要： Two new organobismuth(III) dimethyldithiocarbamates, i.e. [2-(Me 2 NCH2)C6H4]Bi(Cl)(S-2 CNMe2) (4) and [2-(Me2NCH2)C6H4]Bi(S-2 CNMe2)(2) (5), were obtained and their potential use as single source precursors for obtaining Bi-2 S-3 was investigated. Compound 5 shows clean decomposition to Bi2S3 in the 220-320 degrees C temperature range, while in the case of 4 decomposition is plagued by a potential redistribution process. DFT, NBO and Hirshfeld surface analyses were carried out for the starting material [2-(Me2NCH2)C6H4]Li (1) and the new compound 5 in order to understand the nature of intra- and intermolecular bonding interactions and the results were compared with those observed experimentally by single crystal X-ray diffraction. (C) 2021ElsevierB.V. Allrightsreserved.

关键词： beta-keto-enol   alpha-glucosidase   Docking   DFT   Thermal   XRD  

摘要： The new (Z)-pyrazol beta-keto-enol as model-molecule has been prepared in accepted high yield;the structure was investigated by X-ray single crystal diffraction (XRD) and Density Functional Theory (DFT) modeling. Several hydrogen bonds interactions were recorded experimentally via XRD and theoretically via Hirshfeld surface analysis (HSA) calculations. The recorded vibrational frequencies FT-IR were further compared to computed ones. Natural Population Analysis (NPA), Mulliken Atomic Charge (MAC), and Molecular Electrostatic Potential (MEP) has been carried out to complete the set of theoretical tools. The HOMO/LUMO, density of state (DOS) and TD-SCF/DFT were applied to compare these quantum parameters with experimental electron transfer and direct optical activity. DFT calculations, natural bond orbital (NBO) analysis and non-covalent interactions (NCI) analysis were used to explore the mechanism of the single proton keto-enol intra-migration tautomerization reaction. Additionally, the desired compound was screened for its in-vitro alpha-amylase and alpha-glucosidase inhibitory activities. The title compound reflected a potent inhibitory activity alpha-glucosidase enzyme with IC50 value of 72.20 +/- 1.50 mu M. Moreover, the solved 3D-crystal structure was used for 1BNA DNA docking evaluation. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Clay   Extrudates   Citronellal cyclization   Bentonite   Attapulgite   Sepiolite   Palygorskite  

摘要： Four clay materials, namely, bentonite, bleaching earth, attapulgite and sepiolite, were shaped into the cylindrical body by extrusion. Clays were characterized in depth by TEM, SEM-EDX, N2 physisorption, pyridine FTIR, pH measurements, contact angle measurements, 27Al MAS NMR, and the crush test. Catalytic properties were investigated in the citronellal cyclization as a model reaction. The reaction was performed in the trickle-bed reactor at 70 degrees C, 10 bar of Ar with 0.086 M initial citronellal concentration in cyclohexane. The best results were obtained over attapulgite with isopulegols yield of 24% and stereoselectivity to the desired isopulegol isomer of 61%. Attapulgite had the highest meso-to-micropore volume ratio, the highest basicity, a low Bronstedto-Lewis acid sites ratio, and the lowest amount of Bronsted acid sites compared to other extrudates. In addition, same clay exhibited the highest mechanical strength of extrudates.

关键词： Palladium phthalocyanine   Nickel phthalocyanine   Antibacterial photodynamic therapy   Singlet oxygen   Methicillin-resistant Staphylococcus aureus   Aeromonas hydrophila  

摘要： Four novel tetra non-peripheral 2-hydroxypyridine substituted palladium (II) and nickel (II) phthalocya-nines and their quaternized derivatives were synthesized. The phthalocyanines were fully characterized by different spectroscopic methods such as UV-Vis, FT-IR, 1 H NMR and MALDI-TOF mass spectrome-try. The quaternized phthalocyanines showed solubility in DMSO and water within a wide concentra-tion range and with lack of aggregation behavior. The singlet oxygen generation properties were deter-mined for quaternized phthalocyanine complexes in DMSO, water, and water + TritonX 100 solutions. The uptake capability and in vitro photodynamic activity studies performed on two pathogenic bacteria namely Gram (+) Methicillin-resistant Staphylococcus aureus (MRSA) and Gram (-) Aeromonas hydrophila suggested good potential of palladium (II) phthalocyanine complex (5) for the uptake and inactivation of planktonic cultured bacteria. Significant localization of water-soluble Pd(II) phthalocyanine complex was observed for MRSA biofilms. However, this resulted in low efficiency of pathogen inactivation. The newly synthesized nickel (II) phthalocyanine (6) showed lack of inactivation towards both bacterial strains under the applied mild treatment conditions. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Powders  

摘要： In this study, production of instant beverage powder by the foam-mat drying method (foam-mat freeze- and hot-air drying) from red beetroot, quince fruit, and cinnamon extracts without and with maltodextrin (MD) (0%, 10%, 20%, and 30%) were investigated. The results showed that an increase in the MD level has led to a decrease in the moisture content of powders. Drying method and MD concentration had a significant effect on rehydration time, color, and total phenolic content (p & LE;0.05). Foam-mat hot-air-dried powder containing 20% MD had a good flowability. According to the statistical analysis, MD content had a more significant effect on the antioxidant activity of powders than the drying method (p & LE;0.05). The total phenolic content of foam-mat hot-air-dried powders was higher than that of foam-mat freeze-dried powders. Based on the results, the produced powder containing 20% MD via foam-mat hot-air drying (60 & DEG;C) was the optimum sample.