ZnO microparticle-loaded chitosan/poly(vinyl alcohol)/acacia gum nanosphere-based nanocomposite thin film wound dressings for accelerated wound healing

The present study deals with the development of novel ZnO microparticle-loaded chitosan/poly(vinyl alcohol)/acacia gum nanosphere-based nanocomposite thin films through electrospraying and evaluation of their potential use in wound healing applications for skin. ZnO microparticles were synthesized and used as bioactive agents. Morphology, size distribution, structure, and dispersion of the synthesized ZnO microparticles were analyzed by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy (TEM). ZnO microparticles were incorporated into the ternary nanocomposite films by electrospraying technique. Thermogravimetric analyses reveal that incorporation of ZnO microparticles into the nanocomposite structure improves the thermal stability. Mechanical analyses show that tensile strength reaches to the maximum value of 12.75 MPa with 0.6 wt % ZnO content. SEM and TEM micrographs demonstrate that the nanocomposite films consist of nanospheres with nanocapsular structures whose sizes are mostly between 250 and 550 nm. Viability tests established prevailing cellular performance of the fibroblasts on 0.6 wt % ZnO microparticle-loaded nanocomposite films with a viability percentage of 160% compared to the control group. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48445.     

A review of recent laboratory research and commercial developments in fast pyrolysis and upgrading

Robust alternative technology choices are required in the paradigm shift from the current crude oil-reliant transport fuel platform to a sustainable, more flexible transport infrastructure. In this vein, fast pyrolysis of biomass and upgrading of the product is deemed to have potential as a technology solution. The objective of this review is to provide an update on recent laboratory research and commercial developments in fast pyrolysis and upgrading techniques. Fast pyrolysis is a relatively mature technology and is on the verge of commercialisation. While upgrading of bio-oils is currently confined to laboratory and pilot scale, an increased understanding of upgrading processes has been achieved in recent times.     

The effects of different materials as dough improvers for organic whole wheat bread

In this research, the effects of different materials such as defatted Cephalaria syriaca flour (0.5%), rosehip (2.5%), vital gluten (2.5%) and malt flour (2%), and their combinations on the quality of organic whole wheat flour were investigated. The highest maximum resistance value was obtained in the treatment containing 0.5% cephalaria and 2.5% rosehip. The addition of malt flour and vital gluten significantly increased the extensibility value. Although rosehip, cephalaria and vital gluten generally increased the dough energy, malt flour decreased the dough energy when compared to the control. The combination of 0.5% cephalaria and 2.5% rosehip significantly decreased the adhesion and stringiness of dough. Data showed that dough rheological characteristics of organic whole wheat flour could be improved with the addition of different materials such as malt flour, cephalaria, rosehip and vital gluten.     

Bio-oil Production from an Oilseed By-product: Fixed-bed Pyrolysis of Olive Cake

Abstract

A study of pyrolysis of olive cake at the temperature range from 400°C to 700°C has been carried out. The experiments were performed in a laboratory scale tubular reactor under nitrogen atmosphere. The yields of derived gases, liquids, and char were determined in relation to pyrolysis temperature and sweeping gas flow rates, at heating rates of about 300°C min^?1. As the pyrolysis temperature was increased, the percentage mass of char decreased whilst gas product increased. The oil products increased to a maximum value of ～39.4 wt% of dry ash free biomass at a pyrolysis temperature of about 550°C in a nitrogen atmosphere with flow rate of 100 mL min^?1 and with a heating rate of 300°C min^?1. Results showed that the bio-oil obtained under the optimum conditions is a useful substitute for fossil fuels or chemicals.     

Use of Brink Depth in Discharge Measurement

The behavior of free surface flow at a rectangular free overfall is studied experimentally to obtain a relation between the brink depth and the flow rate. A series of experiments were conducted in a tilting flume with wide range of flow rates covering subcritical, critical, supercritical regimes, and two different roughnesses in order to develop a relationship between the discharge and the brink depth. An equation is proposed to determine the flow rate using the brink depth for a channel of known roughness and bed slope.     

Delivery and impact bypass in a karst aquifer with high phosphorus source and pathway potential

Conduit and other karstic flows to aquifers, connecting agricultural soils and farming activities, are considered to be the main hydrological mechanisms that transfer phosphorus from the land surface to the groundwater body of a karstified aquifer. In this study, soil source and pathway components of the phosphorus (P) transfer continuum were defined at a high spatial resolution; field-by-field soil P status and mapping of all surface karst features was undertaken in a > 30 km² spring contributing zone. Additionally, P delivery and water discharge was monitored in the emergent spring at a sub-hourly basis for over 12 months. Despite moderate to intensive agriculture, varying soil P status with a high proportion of elevated soil P concentrations and a high karstic connectivity potential, background P concentrations in the emergent groundwater were low and indicative of being insufficient to increase the surface water P status of receiving surface waters. However, episodic P transfers via the conduit system increased the P concentrations in the spring during storm events (but not >0.035 mg total reactive P L⁻¹) and this process is similar to other catchments where the predominant transfer is via episodic, surface flow pathways; but with high buffering potential over karst due to delayed and attenuated runoff. These data suggest that the current definitions of risk and vulnerability for P delivery to receiving surface waters should be re-evaluated as high source risk need not necessarily result in a water quality impact. Also, inclusion of conduit flows from sparse water quality data in these systems may over-emphasise their influence on the overall status of the groundwater body.     

Removal of textile dye from aqueous solution by electrochemical method

The use of adsorption and electrochemical treatment technologies for wastewater treatment has significantly increased in recent years. In the present study, carbon prepared from biomass waste can be used as electrode material in the electrochemical process is shown. Given that the electrode material is quite expensive, low-cost manufacturing is gaining more and more importance. Electroadsorption of textile dye (Burdem Orange II) by using activated carbon prepared from waste material, which is cherry stones, was investigated with the variation in the parameters of pH, initial dye concentration, solution flow rate, applied potential, and supporting electrolyte. The removal efficiency of textile dye up to 98% were achieved by electrochemical method.     

Geometry design model of a precise form-milling cutter based on the machining characteristics

This paper presents a new approach to design a form milling cutter for precisely obtaining the complex free-form surfaces. In this study, the intersection point of the rake surface, helix flute and clearance flank is appropriately defined due to its significant role in the design and grinding performance. The angle-solid-block analysis is developed to establish the new cutter geometry model. Hence, a new form-milling cutter satisfying the requirements of machining characteristics of workpiece can be designed. In addition, the cutter geometric model can be adopted to map out the measuring strategy with minimum measured points to attain the exact geometric feature of cutter.     

Economic restructuring in Eastern Europe and acid rain abatement strategies

Acid rain abatement in Europe are currently being discussed in view of the expiration of the Helsinki Protocol on SO₂ emission reduction. The changing energy situation in Eastern European countries is expected to have an influence on the deposition pattern in Europe. The paper presents a consistent energy scenario for Eastern European countries and compares optimal strategies to reduce SO₂ emissions. These strategies are based on runs with the RAINS model in which environmental targets have been set based on critical loads for sulphur. The analysis shows that economic restructuring and efficiency improvements in Eastern European countries, as well as in Western Europe, may result in significantly lower sulphur abatement. costs. Potential assistance to Eastern Europe to guarantee desired environmental standards in Western countries should therefore focus not only on providing emission control devices but also on the success of the economic transition process.     

Comparative findings on the stereoselectivity of cholinoreceptors

The potency of the optical isomers of the muscarinomimetic agent 2-methyl-4-dimethylaminomethyl-1.3-dioxolane methiodide (F-2268) was compared on cholinoreceptors, (ChR) of different animals. The greatest difference between optical isomers was observed on the muscarinic ChR of guinea pig ileum smooth muscle cis-L(+)isomer being more than hundred times as potent as cis-D(-)isomer. On the ChR of muscarinic type in the holothuria Cucumaria japonica retractor muscle, cis-L(+)isomer was 25 times as efficient as cis-D(-)isomer. On the ChR of sea urchin and sipunculid locomotor muscles, optical isomers differ only 3 to 5 times. There was no difference between the effect of optical isomers on the ChR of muscarinic type which mediate hyperpolarization in the neurones of the gastropod mollusc Planorbarius corneus. This suggest that some changes in ChR stereoselectivity may occur in the course of evolution.