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关键词： porphyry deposits   gold   copper   fluid inclusions   temperature   salinity   pressure   depth  

摘要： Fluid inclusions were studied in quartz from economic ores of the Svoboda area, which is one of the main economic areas of the Malmyzh Au-Cu porphyry deposit. The economic Au-Cu mineralization of the deposit formed mostly from chloride fluid. The main physicochemical parameters of the ore-forming include a temperature of 250-350 degrees C, a salinity of 0.8-48.0 wt % NaCl equiv., and a pressure of 15-62 MPa. The calculations of the pressure of ore-forming fluid indicate the depth of the formation of ore mineralization in a range of 1.5-2.4 km and a 900 m ascent of the ore-hosted block during ore deposition. Our data can be used during prospecting and exploration works at Au-Cu porphyry deposits.

关键词： CO2 leakage monitoring   Shallow carbonate freshwater aquifer   CO2-rock-water interactions   Field experiment   CO2 geological storage  

摘要： This work is part of the Aquifer CO2-Leak project and aims to understand, quantify and model the environmental impact of a CO2 leak on water quality in the carbonate freshwater aquifer as well as CO2-water-carbonate interactions. The experiment has been performed within an Oligocene carbonate underground quarry located in Saint-Emilion (France). A water charged with dissolved CO2 was injected in the aquifer through a borehole. Downstream, seven wells were fitted with in-situ probes which automatically measured physicochemical parameters. Periodic water samplings in all wells have been undertaken to determine the elemental concentrations by ion chromatography. The spread of CO2 in the groundwater was monitored as a function of time and was observed to influence the various physicochemical parameters. Five parameters seem to be excellent indicators for monitoring a gas plume during CO2 geological storage in regard to our results: electrical conductivity and pH, and Ca2+, HCO3-, and CO2(aq) concentrations. The interaction between CO2 and limestone is highlighted by a saturation index (SI) calculated with PhreeqC software. It shows (i) a slight trend to dissolution of calcite in the injection well (SI < 0) linked to the reaction process between CO2-H2O-CaCO3 and (ii) a transport process via diffusion for the observation wells with a SI similar or equal to 0. The evolution of physicogeochemical signatures in the aquifer allows us to understand the reactive and transport processes that occur during the migration of a gasified water plume in the context of leakage from a geological storage reservoir. Our results will make possible to model a leakage in a complex natural reservoir.

关键词： Patty   Textured vegetable protein   Extrusion   Physicochemical property   Plant protein  

摘要： Isolated soy protein, wheat gluten, and starch at ratio 5:4:1 were texturized under different moisture contents (40 and 50%) and die temperature (130 and 150 degrees C) by the twin-screw extruder. Physicochemical properties were firstly studied. These textured vegetable proteins (TVPs) were used to form 100% plant-based burger patties. Cooking and textural features were secondly investigated. TVP at 50% moisture content and 130 degrees C die temperature represented the highest water absorption capacity and integrity index but the lowest solubility among TVPs. Cooking loss and shrinkage in diameter and thickness, cohesiveness, chewiness, hardness, and cutting strength of TVP meatless burger patties were significantly lower than that commercial meat patty, while moisture retention and springiness of TVP meatless burger patties were higher (p < 0.05). Our results found that the texture of patty made with TVP at 50% moisture content and 130 degrees C die temperature was the most similarity to commercial meat patty.

关键词： Silica  

摘要： Agaricus bernardii was a typical mushroom in Inner Mongolia, China, with high metabolic rate, respiration rate and dehydration. The storage time of A. bernardii was very short. It was necessary to prolong postharvest storage. This study was to determine the physicochemical and selected enzyme activities of A. bernardii packed with different barrier packaging materials. The materials concluded low-density polyethylene (PE), poly(butylene adipate-co-terephthalate)/poly(l-lactic acid) (PBAT/PLLA), PBAT/PLLA/hydrophobic silica (0.5S SiO2) and polyamide/PE, respectively. The performance analysis of the materials, gas composition, sensory quality, physicochemical properties, nutritional quality, and index of senility of the mushrooms were measured. The results indicated that the low O-2 (<1%) and moderate CO2 levels (4-7%) in 0.5S SiO2 film maintained a high level of soluble protein, soluble sugar, ascorbic acid, and phenolic contents, inhibited the increase of malondialdehyde, increased the antioxidant enzymes activities of peroxidase and decreased the enzymes activities of polyphenol oxidase. The quality index of the mushroom packed in the 0.5S SiO2 film remained a good condition and kept the market value after 15 days of storage. Practical applications The biodegradable poly(butylene adipate-co-terephthalate)/poly(l-lactic acid) (PBAT/PLLA/SiO2) film has a suitable water vapor permeability and CO2/O-2 permeability radio, which could establish a suitable steady-state inner atmosphere and maintain quality of mushrooms. Compared with the other films, PBAT/PLLA/SiO2 film kept the market value after 15 days of storage and the application of 0.5S SiO2 film could have potential on maintaining the quality of postharvest of Agaricus bernardii. Moreover, expected to replace the nondegradable food packaging material.

关键词： Pelletized lime kiln dust   Liming materials   Soil pH  

摘要： Lime kiln dust (LKD) is a fine particulate material by-product produced during the lime burning processes. Current reuse options are chiefly focused on reuse in the cement industry which are limited by the inherent porosity of this by-product. Due to the presence of calcium (Ca), magnesium (Mg) and other elements which can serve as micronutrients to the plants, LKD has the potential to be used as a replacement for conventional liming materials for both soil pH(KCl) increase and plant supplement with secondary major- (Ca and Mg) and micronutrients (Mn, Cu, Zn and Ni). The work described here outlines the investigation of physicochemical properties of pelletized LKD materials and their effect on soil pH(KCl), available Ca and Mg content in the soil as well as straw and grain yields of spring barley. LKD were analyzed using X-ray diffraction, scanning electron microscopy with energy dispersive analysis, while detailed chemical analysis of both pelletized LKD and soil was performed using Atomic Absorption Spectroscopy. Pellet size and major element composition were used as chief indicators for the liming capacity of LKD. It was shown that low acidic soil (pH(KCl) 5.4) can be conditioned using fine (0.1-2 mm) pelletized LKD due to the high release rates while coarse pellets (5-8 mm) did not significantly increase available Ca and Mg content in soil and did not reach optimum pH(KCl) range even after 48 weeks. The highest application rate of LKD at 4 t/ha increased spring barley grain yield compared to control but the increase was not statistically significant. Thus, pelletized lime kiln dust could be a potential alternative to natural limestone or dolomite minerals as liming material for acid soils with the pellet size determining the liming kinetics. [GRAPHICS] .

关键词： FTIR spectroscopy   Raman spectroscopy   Mossbauer spectroscopy   thermal analysis   calorimetry   enthalpy of formation   aluminocopiapite  

摘要： The natural basic aqueous aluminum and iron sulfate, aluminocopiapite (Al0.60Fe0.073+) Fe-4.00(3+)[SO4](6.03)(OH)(1.95) center dot 19.54H(2)O (Blyava, South Urals, Russia), was studied using powder X-ray diffraction, infrared and Mossbauer spectroscopy, and thermal analysis. The enthalpy of formation from the elements Delta H-f(el)0(298.15 K) = -11 826 +/- 58 kJ/mol was determined by high-temperature melt solution calorimetry on a Tian-Calvet high-temperature heat-flux microcalorimeter "Setaram" (France). Standard entropies and Gibbs energies of formation were estimated for the studied aluminocopiapite and other copiapite-group minerals.

关键词： Lamotrigine   Cocrystal   Solubility   Single-crystal structure   Hirshfeld surface analysis  

摘要： Nowadays, pharmaceutical cocrystals are an alternative approach to the synthesis of new solids without altering active pharmaceutical ingredients of the drug. In this study, lamotrigine (LTG) theophylline (THP) cocrystal monohydrate (1:1:1) and LTG glutarimide (GLU) cocrystal (1:1) were synthesized and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, and Fourier transform infrared analysis. The Hirshfeld surface and 2D fingerprint of the LTG molecule in LTG-THP-H2O and LTG-GLU indicated that the main intermolecular forces between two LTG coaystals molecules are H center dot center dot center dot N/N center dot center dot center dot H and H center dot center dot center dot O. Dissolution results and stability studies demonstrated that the properties of LTG were enhanced by coaystal formation. Contrary to LTG-GLU, LTG-THP-H2O posed slower dissolution rate and higher stability capability, which can be ascribed to the hydrated structure in LTG-THP-H2O and the aminopyridine dimer structure in LTG-GLU. Hence, it is necessary to select the conformers purposefully as to improve the corresponding performance of LTG. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Cassava   fermentation   men   physicochemical properties   women  

摘要： Cassava breeding programmes in Uganda do not currently select materials based on flour making quality, explaining in part the low adoption rates of many released varieties. In this study, we describe end user trait preferences, processing qualities and physicochemical properties of cassava flour. We found that higher proportion of women than men showed preference for most attributes of cassava flour quality evaluated in this study. Preference for colour was 66% and 52% among women and men, respectively, while that for stickiness of Kwon was 26% (women) and 15% (men). Ease of peeling and stickiness of Kwon were key processing traits. Heap fermented flour had higher pasting temperatures, but lower viscosities than sun-dried flour, and had lower amylose content compared to fresh root starch. The results demonstrate the importance of gender sensitive participatory evaluation of breeding materials, in tandem with physicochemical evaluation during selection of best possible candidate breeding lines.

关键词： Solvent treatment   Crystallization   Flowability   Compressibility   Ofloxacin  

摘要： Purpose To investigate the potentials of a simple solvent treatment technique for improving the physicochemical and mechanical properties of ofloxacin. Methods Ofloxacin was treated with 5% aqueous ammonia solution at a solid to solvent ratio of 1:3 and treatment time of 4 h in stoppered flasks, then filtered under vacuum. Changes in ofloxacin powder characteristics were monitored using SEM, particle size analysis, IR, DSC, XRD, hydrophilicity, equilibrium solubility, dissolution rate, flowability, and compressibility tests. The effect of PVP K90 and Tween 80 used in two concentrations (0.2% and 2%) was investigated. Crystals of ofloxacin having particle size < 160 mu m were included whenever appropriate for comparison. Results The treated ofloxacin showed bundles of elongated prisms with a wide particle size range (2 to 39 mu m). Average size was reduced from 9.8 to 6.4 and 4.6 mu m with 2% Tween 80 and PVP, respectively. Different analytical techniques confirmed that neither structure modification nor additive molecule incorporation in crystal lattice occurred during treatment. The treated powder showed repose angle 39 degrees, bulk density 0.282 g/cm(3), tap density 0.319 g/cm(3), Hausner ratio 1.13, Carr's index 11.6%, compact hardness 5-6.45 kg, porosity 13-6.38%, and elastic recovery 4.5-8.8%. The corresponding values for untreated ofloxacin were 59.5 degrees, 0.221 g/cm(3), 0.314 g/cm(3), 1.42, 29.6%, 3.74-5.27 kg, 15.38-7.22%, and 4.57-8.83%, respectively. Values were further improved by PVP addition. Conclusions Treating ofloxacin powder with 5% aqueous ammonia solution in the presence of 2% PVP improves the dissolution, flowability, and compressibility of the drug. The treated powder is suitable for the preparation of tablets with few excipients.

关键词： biostimulation   polycyclic aromatic hydrocarbons   oil contamination   biodegradation  

摘要： Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants that are mutagenic, carcinogenic, and toxic to living organisms. Here, the ability and effectiveness of selected bacteria isolated from an oil-contaminated area in biodegrading PAHs were evaluated, and the optimal conditions conducive to bacterial PAH biodegradation were determined. Of six bacterial isolates identified based on their 16S rRNA sequences, Planomicrobium alkanoclasticum could subsist on and consume nearly all hydrocarbons according to the 2,6-dichlorophenolindophenol assay. The efficacy of this isolate at PAH biodegradation was then empirically confirmed. After 30 days of incubation, P. alkanoclasticum degraded 90.8% of the 16 PAH compounds analyzed and fully degraded eight of them. The optimum P. alkanoclasticum growth conditions were 35 degrees C, pH 7.5, and NaNO3 as the nitrogen source. Under these biostimulant conditions, P. alkanoclasticum degraded 91.4% of the total PAH concentrationand completely decomposed seven PAHs after 15 days incubation. Hence, P. alkanoclasticum is an apt candidate for the biodegradation of PAHs and the bioremediation of sites contaminated by them.