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关键词： Electrostatic complexing   Water-proof   Thermal stability   Mechanical property   UV blocking  

摘要： Various biodegradable or edible films were designed to deal with the environmental threats from plastic films. To overcome the defects of pectin film, the feasibility for the incorporation of CH/PE fiber was explored. Micron-scale novel artificial CH/PE fibers in needle, spindle or whisker shape with a diameter around 25 mu m were fabricated via a shearing regime in virtue of electrostatic complexing. The incorporation of CH/PE fiber (mixture) and its sizefractioned portions (small and large) substantially changed PE films in diverse ways. Structurally, the fiber incorporated films were heterogeneous with the fibers concentrated in the upper layer, although they presented similar FT-IR spectra and XRD pattern to PE film. Regarding the film performance, the incorporation of CH/PE fibers, especially the small portion, rendered the PE film with higher values in water-proof ability, thermal stability, break resistibility, stretchability and UV blocking capacity. More importantly, this work provided an innovative strategy to improve the performance of edible films. (C) 2020 Elsevier B.V. All rights reserved.

关键词： A. lobatum kernel oil   Physicochemical properties   Fatty acids   Squalene   Tocopherols   Supercritical CO2 extraction  

摘要： There are limited studies available regarding the characteristics of Actinostemma lobatum Maxim. kernels. In the present study, the kernels were analyzed for their nutritional composition, especially their oil characteristics. Expressed on the dry weight basis, the kernel oil accounted for 47 % of the kernel, whereas the content of protein represented 26 %. The major unsaturated fatty acids of the kernel oils were linoleic acid and oleic acid (43 %-44 % and 37 %-38 %, respectively). The kernel oils were found to be rich in squalene, tocopherols, and phytosterols (2327-2975, 676-759, and 504-676 mg/kg, respectively). More specifically, delta-tocopherol was the most abundant tocopherol and Lambda(5)-avenasterol was the major sterol in the kernel oils. Furthermore, three different oil extraction methods (supercritical CO2 extraction, Soxhlet extraction, and cold pressing) were applied and the physicochemical properties of the extracted oils were compared. No significant differences (P > 0.05) were found in tocopherol and sterol contents for the three extraction methods. Higher oil yield and oil recovery were obtained by supercritical CO2 extraction. Overall, A. lobatum kernel is a promising valuable source of bioactive substances and essential fatty acids for future applications in food, pharmaceutical, and cosmetic industries.

关键词： Microalgae   Freshwater aquaculture   Waste treatment   Resource utilization   Sustainability  

摘要： There has been growing interest in exploiting microalgae as a natural process for low cost wastewater treatment and for water quality control and remediation in aquaculture. This constitutes the first study to report on a strong relationship between use of sophisticated wet-laboratory flow cytometry equipment and in-field AlgaeTorch (R) technologies for determining microalgae and bacteria population dynamics in a freshwater pill-pond aquaculture farm over a 10-month monitoring period producing Eurasian Perch, Perca fluviatilis, in the Republic of Ireland. Nitrate levels and temperature were the most significant factors influencing microalgae numbers in rearing and treatment ponds as determined by Principle Component Analysis. Variance in climate, namely drought conditions that occurred during monitoring period, did not affect microalgae or microbial numbers. Chlorophyta, Bacillariophyta and Cryptophyta were the most dominant algal divisions observed in this recirculating aquaculture system, many of these are recognized as a natural source of beneficial prebiotics for fish. Determining baseline microalgal profiles in rearing water, followed by elucidating physicochemical parameters governing wastewater treatment performance, can inform future intensification and diversification of freshwater aquaculture by exploiting and replicating knowledge of favourable algal-microbial ecosystems. Furthermore, holistic datasets can be utilised for smart agriculture by way of informing management tools for future remote monitoring and decision-making by producers.

关键词： Na secondary batteries   Ionic liquids   (fluorosulfonyl)(trifluoromethylsulfonyl)amide   Hard carbon  

摘要： In this study, thermal, physical, and electrochemical properties of the ionic liquid electrolyte system, Na[FTA]-[C(3)C(1)pyrr][FTA], (FTA(-) = (fluorosulfonyl) (trifluoromethylsulfonyl)amide and C(3)C(1)pyrr(+) = N-methyl-N-pro-pylpyrrolidinium) have been investigated for Na secondary batteries. The asymmetric FTA. structure provides a wide liquid-phase temperature range, especially at low x(Na[FTA]) (x(Na[FTA]) = molar fraction of Na[FTA]) and low temperature range. Glass transition at 170-209 K is the only observed thermal behavior in the x(Na [FTA]) of 0.0-0.4. Temperature dependence of viscosity and ionic conductivity obeys the Vogel-Tammann-Fulcher equation, and the correlation between molar conductivity and viscosity follows the fractional Walden rule. The anodic potential limits are above 5 V vs. Na+/Na at 298 and 363 K. The noticeable effects of x(Na [FTA]) are observed in the electrochemical performance of Na metal and hard carbon electrodes. In both cases, a moderate concentration, x(Na[FTA]) of 0.2-0.3, enables favorable charge-discharge behavior. At 363 K, the discharge capacities of the hard carbon electrode at x(Na[FTA]) of 0.3 are 260 and 236 mAh g(-1) at the current densities of 20 and 200 mA g(-1), respectively. The optimum cycling performance occurs at x(Na[FTA]) = 0.3, providing satisfactory capacity retention and high average Coulombic efficiency.

关键词： Faba bean starch   Cross linking   Physicochemical   Thermal   Pasting   Film forming properties  

摘要： Faba bean starch was crosslinked (CL) at different levels (1, 3 & 5%) using sodium trimetaphosphate and studied for physicochemical, thermal, pasting and in vitro digestibility characteristics. Further, films were prepared from these starches and characterized for moisture content, thickness, water solubility, opacity, water vapor permeability (WVP) and mechanical properties. Amylose content, swelling power and solubility decreased after modification. CL resulted in decrease in peak viscosity (PV) whereas pasting temperature increased;CL (5%) showed the lowest PV (6474 mPa.s). Steady shear properties showed flow behavior index values b1 for starch pastes, indicating pseudoplastic and shear-thinning behavior. Thermal properties of CL starches showed higher transition temperatures and enthalpy of gelatinization (Delta H-gel) as compared to native starch. Delta H-gel values of CL starches ranged from 10.70 to 14.20 J/g whereas for native starch, the value was 9.47 J/g. CL resulted in increased resistant starch (from 49.8 to 61.1%), the highest value was for CL (5%). CL starch films exhibited lower moisture content, water solubility and WVP. Film thickness, however, was not affected by modification. CL (5%) starch film showed the highest tensile strength (14.28 MPa) and the lowest elongation at break (25.62%). CL resulted in improved mechanical and barrier properties of starch films. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Heavy metals  

摘要： In response to the global energy crisis and damage to humans by environmental issues, metal oxide nanomaterials (nonprecious) represent an important class of materials for energy conversion and environmental detection on account of their natural abundance, easy synthesis, low cost, and excellent stability. A majority of pristine metal oxide nanomaterials have certain shortcomings in catalysis and sensing, such as poor conductivity and wide bandgap. Fortunately, the regulation of the intrinsic physicochemical properties of metal oxide nanomaterials is a very promising approach for improving their catalytic and sensing properties for energy conversion and environmental detection. In this review, we will mainly discuss the regulation of the intrinsic physicochemical properties, namely, shape and size, defects, crystal facets, and ion cycles of metal oxide nanomaterials, with a majority of applications involving photocatalytic water splitting and CO2 reduction, electrocatalytic water splitting, heavy metal ion (HMI) detection, and metal oxide gas sensors. Density functional theory (DFT) calculations and X-ray absorption fine-structure (XAFS) spectroscopy analysis have been used to evaluate the effects of regulation of the intrinsic physicochemical properties of metal oxide nanomaterials, as well as to further identify the relationship between the intrinsic physicochemical properties and their enhanced catalytic and sensing properties with regard to energy conversion and environmental detection. Finally, some unresolved problems associated with future perspectives in this field are discussed, inspiring further development of the intrinsic physicochemical properties of metal oxide nanomaterials.

关键词： Genetics   Molecules   Testing and assessment   Permeability   Conjugate acid-base pairs  

摘要： Cytotoxic pyrrolobenzodiazepine (PBD)-dimer molecules are frequently utilized as payloads for antibody-drug conjugates (ADCs), and many examples are currently in clinical development. In order to further explore this ADC payload class, the physicochemical properties of various PBD-dimer molecules were modified by the systematic introduction of acidic and basic moieties into their chemical structures. The impact of these changes on DNA binding, cell membrane permeability, and in vitro antiproliferation potency was, respectively, determined using a DNA alkylation assay, PAMPA assessments, and cell-based cytotoxicity measurements conducted with a variety of cancer lines. The modified PBD-dimer compounds were subsequently incorporated into CD22-targeting ADCs, and these entities were profiled in a variety of in vitro and in vivo experiments. The introduction of a strongly basic moiety into the PBD-dimer scaffold afforded a conjugate with dramatically worsened mouse tolerability properties relative to ADCs derived from related payloads, which lacked the basic group.

关键词： Aluminum ion battery   Ionic liquid analogues   AlCl3-urea   Speciation   Ionic conductivity   Electrochemical stability   Graphene nanoplatelets  

摘要： Among post Li-ion battery technologies, Al-ion batteries are receiving growing attention due to the high abundance of Al, low cost, ease of handling in an ambient environment, and high theoretical capacities obtained from three-electron redox process. Here, the physicochemical properties of AlCl3 and urea mixtures known as deep eutectic solvents or ionic liquid analogs (ILAs) are investigated by changing the molar ratio of AlCl3/urea in the range of 1.0-1.6. Multinuclear (Al-27, C-13, H-1) nuclear magnetic resonance spectroscopy (NMR), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV) are used to determine the speciation of ionic moieties, ionic conductivity, and electrochemical stability of this complex system. On the basis of the composition-property results, 1.4 molar ratio of AlCl3/urea was selected as the best composition and was used as the electrolyte in an Al-cell made of Al anode and graphene nanoplatelets (GNP) cathode. The battery delivered a specific capacity of 74 mAh g(-1) at 100 mA g(-1), and it retained a specific capacity of similar to 40 mAh g(-1) at a very high current of 1000 mA g(-1). (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Wild-fruit waste   Physicochemical properties   Beneficiation   Mannan  

摘要： Disposal of biomass waste is the foremost challenge facing the industrial and agricultural sectors due to the economic and environmental considerations. Doum fruit is a product of wild-palm (Hyphaene Thebaica) that is widely consumed in some of the African countries. It is considered as one of the most fruits that productive waste (more than 80 wt% of the fruit's weight). Understanding the physicochemical properties of the Doum fruits waste demonstrate their beneficiation. In this context, Doum seeds were collected, cleaned, and milled to a powder. The physicochemical properties of the powder were investigated using proximate and ultimate analyses. The results revealed that ash content, moisture content, and volatile matter were 1.3 wt%, 10.0 wt%, and 85.3 wt%, respectively. The elemental analyses showed that carbon (44.9 wt%), hydrogen (6.66 wt%), oxygen (42.6 wt%) and nitrogen (1.1 wt%), were the main components. High-performance Liquid Chromatography (HPLC) result exposed that 70 wt% of the sugar content of the seed was mannose. Scanning electron microscope (SEM) pictures disclosed that Doum seed characteristic with high and regular porous structure. Spectroscopy analysis revealed that Doum seed has similar functional groups and chemical structure of carbohydrates (mannan). The extraction of mannan was carried out by scouring the seed powder in an alkali solution of sodium hydroxide (NaOH). The optimal conditions of the extraction were determined to as;temperature (90 degrees C), scouring time (1.5 h), and NaOH concentration (0.25 N). A comparison in chemical structure and thermal properties between the extracted mannan and the commercial mannan (lab-grade) was accomplished. The findings demonstrated that Doum seed has the potential for producing high-content mannan materials.

关键词： Atherigona naqvii   Host plant resistance   Phenylalanine ammonia lyase   Polyphenol oxidase   Seedling vigour   Shoot fly   Spring maize  

摘要： Host plant resistance is one of the most promising alternatives to insecticides to manage the shoot fly,Atherigona naqviiSteyskal, which is a major biotic constraint to spring sown maize in northern India. In present studies, Nineteen maize inbreds selected from diverse sources were characterized for resistance traits against shoot fly under its natural infestation using moistened fishmeal. Though the antixenosis to shoot fly for oviposition was not observed in the test genotypes. But, the presence of significant variation in the deadhearts incidence revealed the existence of relative amount of resistance among the test genotypes. The Tolerance (measured in the terms of less proportion of deadhearts out of total shoot fly incidence (leaf injury + deadhearts)) and Antibiosis (in terms of larval and pupal weight, duration and survival) were recognized as key mechanisms of this resistance. Tolerance to shoot fly was significantly more in resistant inbreds, SO1SHYQBBB13B, HK12-6-2-4, DMSC 28, CM 143 and Winpop 8 (29.46-36.56%) in comparison to the susceptible genotypes SE 563 and LM 16 (46.31-47.44%). The correlation and stepwise regression analyses revealed that the more seedling vigor, less leaf area, less number of leaves and thin stem had significant impact on the shoot fly deadhearts incidence and provided resistance against this pest. The total soluble sugars (TSS), proteins and amino acids were significantly higher in the susceptible inbreds;whereas, total phenols and tannins;and activities of defensive enzymes viz. phenylalanine ammonia lyase (PAL) and polyphenol oxidase (PPO) were significantly higher in resistant inbreds. Further, the stepwise regression revealed that the larval period, per cent pupation, pupal weight female, pupal weight male and adult emergence of shoot fly were significantly influenced by PAL activity, which explained 71.5, 82.9, 47.0, 29.8 and 39.9% of their total variation, respectively. PPO activity significantly influenced the pupal per