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In this study, imines bearing quinazolin‐4(3H)‐one were synthesized and their inhibitory properties were investigated against some metabolic enzymes including Acetylcholinesterase (AChE), Butyrylcholinesterase (BChE), α‐Glycosidase (α‐Gly), and human Carbonic Anhydrase I–II (hCA I–II). All compounds had inhibitory strength with Ki values in the range of 38.55±4.08–159.05±10.68 nM and 41.04±6.73–177.12±8.06 nM against hCA I and hCA‐II, respectively in comparison to the standard acetazolamide (AZA) Ki=125.15±0.78 nM (for hCA‐I) and Ki=148.75±0.92 nM (for hCA‐II). The compounds showed potent inhibitory activity against α‐Gly enzyme with IC50 value 0.34–2.28 nM (standard inhibitor acarbose (ACR): 3.18 nM). Also, these analogs had potent inhibitory strength with Ki values in the range of 4.20±0.15–26.10±2.36 nM against AChE and 1.22±0.05–16.09±0.88 nM against BChE in comparison to the standard tacrine (TAC) Ki=37.62±6.86 nM (for AChE) and Ki=26.75±5.79 nM (for BChE). Additionally, the molecular docking and molecular dynamics simulation study was carried out for the determination of ligand‐enzyme interactions. The docking scores of the most active compound were calculated as −7.31, −7.59, −6.66, −6.93 and −7.11 kcal/mol for AChE, BChE, hCA I, hCA II, and α‐Gly, respectively. [ABSTRACT FROM AUTHOR]

In this work, the inhibitory ability and mechanism of ω3‐nicotinic acid (ω3‐NA) and ω3‐Picolinic acid (ω3‐PA) complexes on the activity of mushroom tyrosinase (MT) were scrutinized for progressing a novel MT inhibitor. The complexes were synthesized. It was shown to have a considerable inhibition on the MT activity and Ki value of ω3‐NA and ω3‐PA on MT equal to 5.2 and 5.1 mM, respectively. ω3‐NA and ω3‐PA inhibited MT with Vmax values in the range of 0.134 mM and 0.14 mM, respectively. The outputs obtained from fluorescence quenching specified that ω3‐NA and ω3‐PA could interact with MT. Especially, the decrease in fluorescence intensity was due to the formation of a ligand‐enzyme complex which was mostly motivated by hydrogen bonding and hydrophobic forces. The presence of ω3‐NA and ω3‐PA altered the structure of MT and reduced the α‐helix of the enzyme. Molecular docking investigation along with molecular dynamics simulation exhibited that ligands‐MT formation is directed by hydrogen binding with Trp136, His263, and Val299 residues. The results highlight that ω3‐NA and ω3‐PA can be considered as possible inhibitors in treating hyperpigmentation via MT enzyme inhibition. [ABSTRACT FROM AUTHOR]

Inhibition of intestinal α‐glucosidase (αGS), a crucial enzyme in carbohydrate digestion, is an effective therapeutic approach for diabetes mellitus treatment. The C‐glycosylflavonoids (CGFs) are natural compounds with antioxidant, antidiabetic, and anti‐inflammatory activities. The present work seeks an alternative compound among CGFs that can control the blood glucose level by inhibiting αGS enzyme activity. Therefore, ten CGFs were selected and carried out the docking to αGS. The docking outcomes proposed that among selected CGFs, the orientin compound can successfully interact with the key residues of Asp215, Glu277, Asp352, Arg442, and Arg446. Of them, the orientin compound with docking energy of −6.11 Kcal/mol, was subsequently subjected to molecular dynamics simulation (MDs), and in vitro investigation. MDs results indicated that orientin formed a stable complex with αGS enzyme. We also performed molecular mechanics generalized Born and surface area (MM/GBSA) free energy calculation manner on all chosen CGFs along with miglitol as reference. The IC50 value of orientin for αGS inhibition with competitive mode was found to be 0.13 mg/ml. The results highlight that orientin can be considered as a possible compound in treating DM via αGS inhibition. However, further in vitro and in vivo analyses are required to confirm this claim. [ABSTRACT FROM AUTHOR]

A series of mixed matrix membranes (MMMs) based on polyurethane (PU) and silica nanoparticles was fabricated. Three types of PU were synthesized with different polyethylene glycol (PEG)/polytetramethylene glycol ratios (PU0, PU75, and PU100, the corresponding numbers: PEG percent). The MMMs were characterized using FTIR, SEM, and gas permeation measurements (N2, O2, CH4, and CO2). The phase mixing of PU0 and PU75 membranes increased with silica content. This resulted in a decrease in gas permeability, while an increase in CO2/CH4 and CO2/N2 selectivities. The gas separation trend for PU100 membranes was the opposite. The molecular probing approach was served to study the interfacial structure of the MMMs. The existence of a rigidified polymer layer with 2.38 and 2.44 nm thicknesses around silica was revealed through PU0 and PU75 membranes, respectively. In contrary, silica was surrounded by a polymer chain dilution interphase with a thickness of 2.20 nm for PU100 MMMs. [ABSTRACT FROM AUTHOR]

In this study, (E)‐N′(3,5‐di‐tert‐butil‐2‐hedroxybenzilidene)‐2‐hydroxybenzohydrazide (H3sahz)2 and its copper (II) complex has been synthesized and evaluated by methods FTIR, UV–Vis, EPR, and single crystal X‐ray analysis. It has been shown, that H3sahz crystallizes as a dimer through hydrogen bonds. H3sahz with copper nitrate forms [Cu(H2sahz)(NO3)(H2O)] complex, which according to X‐ray diffraction analysis has a distorted square pyramidal structure. The complex was screened for α‐glucosidase (α‐Glu), acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) inhibitory abilities. Results displayed that IC50 and Ki values of the novel complex for AChE, BChE, and α‐Glu enzymes were obtained at 0.93–2.14, 1.01–2.03, and 73.86–102.65 μM, respectively. The molecular docking outcomes have shown that the synthetic complex has a lower affinity for α‐glucosidase compared to acarbose. But the inhibition ability of H3sahz for acetylcholinesterase and butyrylcholinesterase enzymes was greater than that of tacrine. These findings indicate that the (H3sahz)2 complex may be considered a possible candidate for the development and discovery of compounds effective in inhibiting the relevant enzymes. [ABSTRACT FROM AUTHOR]

During high‐humidity hot air impingement blanching (HHAIB) of fruits and vegetables, the process effect on the product and subsequent process depends on the operating fluid parameters. In this regard, heat transfer phenomenon during applying the pretreatment is not well known. In this study, the mechanisms of heat transfer during the HHAIB of grape berries were investigated via developing an appropriate mathematical model. Numerical simulation of the model was performed using COMSOL software at temperature of 110°C, fluid velocities of 2, 6, and 10 m s−1, and relative humidities of 20%, 40%, 60%, and 80%. The heat transfer caused by the impinging jet and condensation on the grape surface were considered. The center and surface temperature of the grape berries were predicted. Taking the appropriate heat transfer rate and uniformity of temperature distribution in grape berries into account, the relative humidity range of 40%–60% and the velocity of 10 m s−1 were selected for the process. Comparison of the predicted and measured values for the center temperature of the grape berry statistically validated the simulation task with a determination coefficient (R2) of 0.993 and root mean square error of 1.347. Practical Applications: Nowadays, the demand for organic foods has increased. The high‐humidity hot air impingement blanching (HHAIB) is a safe, effective, and controllable nonchemical method that can be used instead of chemical pretreatment in raisin production. In terms of applying the HHAIB pretreatment for grape drying, little research has been done. Thus, there is still no complete understanding of the heat transfer during its application. Numerical simulations are beneficial tools for accurate designing and optimization of thermal processes. Thus, it is necessary to use mathematical modeling to understand HHAIB mechanisms for industrialization. [ABSTRACT FROM AUTHOR]

Purpose: This updated meta‐analysis aimed to assess the diagnostic performance of circulating cell‐free DNA (cf‐DNA) for prostate cancer (PCa). Methods: A systematic search was conducted in PubMed, Scopus, Web of Science, and Embase databases to retrieve related studies. Several diagnostic estimates, including sensitivity (SE), specificity (SP), likelihood ratios (LRs), and diagnostic odds ratio (DOR) were also used to perform the meta‐synthesis. Additionally, the area under hierarchical summary receiver operating characteristic curves (AU‐HSROC) was used as a global measure of test accuracy. Results: Twenty‐nine unique articles were enrolled in the meta‐analysis. Pooled SE and SP for overall accuracy of cf‐DNA in PCa were obtained as 0.54 (95% CI: 0.47–0.61) and 0.92 (95% CI: 0.88–0.95), respectively. Positive LR (PLR) was 6.8 (95% CI: 4.9–9.5, I2: 92.98%) and negative LR (NLR) was 0.5 (95% CI: 0.43–0.58). Pooled DOR was 13.56 (95% CI: 9.49–19.37) and the AU‐HSROC was 0.83 (95% CI: 0.79–0.86). Conclusion: The present study suggested that cf‐DNA assays have comparable SE as well as remarkably higher SP (qualitative assays) than common biomarkers in the detection of PCa like prostate‐specific antigen (PSA). In addition, cf‐DNA assays have better performance in PCa confirmation and almost similar performance to PSA in excluding PCa patients. [ABSTRACT FROM AUTHOR]

The compatibility between polymer matrix and filler is a vital issue in the fabrication of composites with desirable properties. To enhance the interfacial adhesion between matrix and filler, various surface modification treatments are applied. The objective of this study was to increase the affinity of silica and poly(urethane‐urea)s (PUUs), thereby improving the mechanical properties of the resulting composites. Stepwise surface modification of mesoporous silica with amine‐containing dendrimers was done. Various techniques were used to confirm the surface‐modified structure during the stepwise reaction. Additionally, the N2 adsorption–desorption method indicated a gradual reduction in surface area, pore diameter and pore volume of the particles, which warrants the gradual propagation of the dendrimers on the surface and also inside the pores. A type IV isotherm was obtained in this analysis. Two types of pre‐synthesized PUUs were chosen for composite preparation containing the surface‐modified silica with 0.5, 1, 2.5 and 5 wt% concentrations. Due to the high affinity of the dendrimers containing amine moieties on the particles with polyurethane, a proper dispersion of particles in the matrix was achieved based on scanning electron micrographs. Tensile measurements showed an increased Young's modulus and strength of polyurethane films as a result of addition of the particles. However, no significant improvement in the tensile performance of the composites was seen above 2.5 wt% particle loading due to some particle aggregations. © 2021 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

A series of polysulfone (PSF) membranes were prepared using different solvents: dimethylformamide (DMF), tetrahydrofuran, dimethylacetamide, and n‐methyl‐2‐pyrrolidone (NMP). The PSF membrane prepared by NMP showed the highest gas permeability. The influence of propionic acid as a Lewis acid on gas separation properties of the PSF was explored. The PSF membrane prepared by the casting solution containing 25 wt% PSF, 35 wt% propionic acid, and 40 wt% NMP showed a superior gas separation performance. The gas permeation measurements indicated that incorporating 30 wt% γ‐alumina nanoparticles into the PSF matrix resulted in about the respective 43% and 41% increase in CO2 and O2 permeability together with a rise in CO2/CH4 and O2/N2 selectivities (13% and 7%, respectively). Furthermore, by rearranged modified Maxwell model, the role and nature of the interfacial layer in the PSF‐based mixed matrix membranes were mathematically analyzed considering a reduced permeability factor. [ABSTRACT FROM AUTHOR]

The Richardson–Richards equation (RRE) is a widely used partial differential equation (PDE) for modeling moisture dynamics in unsaturated soil. However, field soil moisture observations do not always satisfy RRE. In this paper, we introduce a new physically constrained machine learning (PCML) approach to derive governing soil water flow PDE directly from moisture observations. This paper is viewed as a feasibility study and reports results of our first attempt in developing the PCML approach. Here, we rely on noisy synthetic soil moisture data obtained from the linear RRE subject to real flux boundary conditions. The linear RRE was used as a reference PDE to check the PCML‐derived PDEs, where the PCML performance was shown to be highly dependent upon the sample size in time and space. Results presented here confirm the feasibility of deriving soil water flow governing PDEs directly from soil moisture observations using PCML. Core Ideas: A physically constrained machine learning approach is introduced in soil hydrology.It enables retrieving soil water flow equation(s) from moisture observations.It enables adding new data‐driven terms to the Richardson–Richards equation. [ABSTRACT FROM AUTHOR]

Measurements of the soil water characteristic (SWC) and unsaturated hydraulic conductivity [K(h)] curves, which are at the core of modeling flow and transport processes in porous media, are laborious and prone to experimental errors. To overcome some of the current experimental limitations, we examined the potential feasibility of shortwave infrared (SWIR) imaging of water imbibition into dry soil during a controlled laboratory experiment in conjunction with inverse numerical modeling to determine the wetting SWC and the K(h) function. To generate time series of high‐resolution surface moisture maps, the imaged surface reflectance was converted to surface soil moisture via a recently developed physical radiative transfer model. The moisture time series were then used to parameterize the HYDRUS 2D/3D numerical code for forward simulations. The optimization was performed with simulated annealing in MATLAB that was linked to HYDRUS 2D/3D to automate the inversion process. The obtained SWC wetting curves were subsequently compared with Tempe cell and Dewpoint PotentiaMeter measurements. Although further research and refinements of the proposed method are needed, the results of this exploratory study obtained for a broad range of soil textures are promising and demonstrate the potential feasibility of the proposed approach for rapid estimation of soil hydraulic properties. [ABSTRACT FROM AUTHOR]

In this study, the effect of solvent type and nanoparticles of silica and zeolite 4A on the gas separation properties of polyimide (PI) membranes were investigated. Gas separation of the membranes based on pure solvents of dimethylformamide (DMF), n‐methyl‐2‐pirrolidone (NMP), dimethylacetamide (DMAc), and dimethylsulfoxide (DMSO) were studied. The prepared PI membranes using DMAc and DMSO showed the highest selectivity and permeability, respectively. In this regard, the influence of their mixing on transport properties of the PI was evaluated. The prepared membrane using the mixture of DMSO/DMAc with the volume ratio of 1:3 showed the best gas separation performance in comparison to the Robeson's upper bound. Incorporation of 20 wt% of silica and zeolite 4A nanoparticles into the PI membrane indicated that the selectivity of CO2/CH4 increased from 39.4 to 57.6 and 68.5, respectively. Besides, gas transport properties of the PI‐based mixed matrix membranes were satisfactory predicted by modified Maxwell model. Furthermore, characteristic parameters of the encapsulated particles by interfacial layer were determined. [ABSTRACT FROM AUTHOR]

The increasing need for more efficient separation processes has motivated the development of polymer membranes that can provide fast and selective transport. In this work, cadmium‐based metal–organic framework (MOF) nanoparticles and a polyurethane–urea (PUU) elastomer were synthesized. New mixed‐matrix membranes (MMMs) were then fabricated from the nanoparticles and the PUU. SEM images verified that embedding the nanoparticles changes the morphology of the PUU and the nanoparticles disperse well in the PUU due to satisfactory compatibility of the polymer and nanoparticles. Fourier transform infrared spectroscopy and X‐ray diffraction analysis confirmed the dispersion of the nanoparticles in the soft segment of the PUU. With increased temperature, gas permeabilities of the MMMs improved but their sieving ability deteriorated. An MMM incorporating 2.5 wt % of the MOF showed a CO2 permeability of ~140 barrer and a CO2/N2 selectivity of ~30, which are 89 and 38% higher than those of the pristine membrane. Gas permeation tests showed that the higher CO2/N2 selectivity of the MMMs was due to improved solubility selectivity and the higher CO2 permeability was a result of improved CO2 diffusivity and solubility coefficients. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48704. [ABSTRACT FROM AUTHOR]

The membrane technology has received considerable attention for olefin/paraffin separation in recent years, owing to its attractive energy efficiency. In this study, reduced graphene oxide (rGO) is prepared via hydrothermal treatment of graphene oxide. The prepared rGO is characterized and then incorporated into polysulfone (PSF) to fabricate mixed‐matrix membranes (MMMs). The fabricated membranes are characterized using Fourier transform infrared spectrometry, field emission scanning electron microscopy, and X‐ray powder diffraction. The gas transport properties of the MMMs are evaluated for ethylene/ethane and propylene/propane gas pairs at 2 bar and 30∘C. Permeation tests indicate that the PSF membrane embedded with 1.0 wt% of the rGO nanosheets has 143% and 193% higher C2H4 and C3H6 permeabilities, respectively, its C3H6/C3H8 selectivity is 18% higher, but its C2H4/C2H6 selectivity is 23% lower, compared to those of the pristine PSF membrane. The gas permeability enhancement is attributed to improved gas diffusion and solubility coefficients. These results indicate the potential of rGO nanosheets for the enhancement of olefin permeabilities without significant drops in olefin/paraffin selectivities. [ABSTRACT FROM AUTHOR]

Diabetes is associated with numerous complications, such as diabetic skin wounds or ulcerations. The aim of this study was to evaluate experimentally the effectiveness of applying polycaprolactone (PCL)‐gelatin scaffold, with or without rat CD93 hematopoietic stem cells (HSCs), in diabetic wound healing in a rat model. CD93 HSCs were aseptically isolated from rat bone marrow using fluorescent activated cell sorting (FACS) method and FACS‐SORTER. A total of 25 Wistar rats were divided into five groups including Group I (sham, nondiabetic, and wound covered only with sterile dressing), II (control, diabetic rat), III (CD93 HSCs alone), IV (PCL‐gelatin scaffold), and V (CD93 HSCs+PCL‐gelatin scaffold). Animals were killed on Days 7, 14, or 28 posttreatment and histological sections were blindly evaluated by two expert pathologists. Death‐associated protein kinase 1 (DAPK‐1) gene and vesicular endothelial growth factors (VEGF) protein expression were evaluated using reverse transcription‐polymerase chain reaction and western blot, respectively. The thickest and the thinnest epidermises microscopically were belonged to CD93+HSCs+scaffold and the control group, respectively. The growth rate of the epidermis and adnexal epithelia was the highest in both the cell and cell+scaffold groups. Evaluation of the protein expression level of VEGF indicated that the expression levels of this growth factor were the most on Day 7 posttreatment in sham, HSCs alone, and HSCs cell+scaffold groups. While the lowest expression levels of this growth factor was detected in the control and scaffold groups. The gene expression level of DAPK‐1 on Day 7 posttreatment was higher than that of the Day 14 posttreatment in all groups. The highest and lowest gene expression levels of DAPK‐1 belonged to control and sham groups, respectively. According to our findings, CD93 HSCs offer new prospects for the treatment of diabetic ulcers and concomitant application of these cells with PCL‐gelatin nanofiber scaffold significantly improves diabetic wound treatment. [ABSTRACT FROM AUTHOR]

The separations of ethylene/ethane and propylene/propane using polysulfone‐silica nanocomposite membranes were studied. Silica nanoparticles were prepared via sol‐gel method and the membranes by phase inversion. Characterization by Fourier transform spectroscopy and scanning electron microscopy indicated a good distribution of silica nanoparticles in the polymer matrix and also a good compatibility between the two phases. The performances of the prepared membranes in ethylene‐ethane and propylene‐propane separation were evaluated. The results showed the increments in gas permeability and selectivity by silica. Higher silica contents increased the solubility coefficient and reduced the diffusion coefficient of gases. The plasticization pressure of polysulfone was increased by incorporating the silica nanoparticles in polymer. [ABSTRACT FROM AUTHOR]

Soil moisture (SM) is a key hydrologic state variable that is of significant importance for numerous Earth and environmental science applications that directly impact the global environment and human society. Potential applications include, but are not limited to, forecasting of weather and climate variability; prediction and monitoring of drought conditions; management and allocation of water resources; agricultural plant production and alleviation of famine; prevention of natural disasters such as wild fires, landslides, floods, and dust storms; or monitoring of ecosystem response to climate change. Because of the importance and wide‐ranging applicability of highly variable spatial and temporal SM information that links the water, energy, and carbon cycles, significant efforts and resources have been devoted in recent years to advance SM measurement and monitoring capabilities from the point to the global scales. This review encompasses recent advances and the state‐of‐the‐art of ground, proximal, and novel SM remote sensing techniques at various spatial and temporal scales and identifies critical future research needs and directions to further advance and optimize technology, analysis and retrieval methods, and the application of SM information to improve the understanding of critical zone moisture dynamics. Despite the impressive progress over the last decade, there are still many opportunities and needs to, for example, improve SM retrieval from remotely sensed optical, thermal, and microwave data and opportunities for novel applications of SM information for water resources management, sustainable environmental development, and food security. Key Points: Recent soil moisture measurement and monitoring techniques and estimation models from the point to the global scales and their limitations are presentedThe importance and application of soil moisture information for various Earth and environmental sciences disciplines such as forecasting weather and climate variability, modeling hydrological processes, and predicting and monitoring extreme events and their impacts on the environment and human society are presented [ABSTRACT FROM AUTHOR]

Hydrophilic polyvinyl alcohol membranes, modified by lithium bromide, were prepared with glutaraldehyde as a crosslinking reagent. The membranes were investigated for the pervaporation dehydration of a water–isopropyl systems. The effect of the feed temperature on permeation flux and membrane selectivity was studied. The characterization of modified membranes was performed using Fourier transform infrared spectroscopy (FT‐IR), differential scanning calorimeter (DSC) and X‐ray diffraction. It was observed that the crystallinity of membranes increased as lithium bromide was added to the polymer. High performance liquid chromatography (HPLC) was used to analyze water content and isopropyl alcohol in the feed and permeate samples The pervaporation tests also confirmed an enhancement in water permeability through adding LiBr to the polymer, because of the high hydrophilic properties of this salt. According to pervaporation experiments conducted at 50°C, the water flux increased from 0.1049 kg/ m2 hr to 0.1114 kg/ m2 hr as 0.5 wt% of LiBr was added to the polymer matrix. Furthermore, an addition of 1 wt% of LiBr compared to homogeneous PVA membrane increased selectivity from 76 to 779. POLYM. ENG. SCI., 59:E101–E111, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Abstract: Thermal conductivity is an essential component in multiphysics models and coupled simulation of heat transfer, fluid flow, and solute transport in porous media. In the literature, various empirical, semiempirical, and physical models were developed for thermal conductivity and its estimation in partially saturated soils. Recently, Ghanbarian and Daigle (GD) proposed a theoretical model, using the percolation‐based effective‐medium approximation, whose parameters are physically meaningful. The original GD model implicitly formulates thermal conductivity λ as a function of volumetric water content θ. For the sake of computational efficiency in numerical calculations, in this study, we derive an explicit λ(θ) form of the GD model. We also demonstrate that some well‐known empirical models, e.g., Chung‐Horton, widely applied in the HYDRUS model, as well as mixing models are special cases of the GD model under specific circumstances. Comparison with experiments indicates that the GD model can accurately estimate soil thermal conductivity. [ABSTRACT FROM AUTHOR]

The concept of mixed matrix membrane comprising dispersed inorganic fillers into a polymer media has revealed appealing to tune the gas separation performance. In this work, the membranes were prepared by incorporation of mesoporous silica into polyurethane (PU). Mesoporous silica particles with different pore size and structures, MCM‐41, cubic MCM‐48 and SBA‐16, were synthesized by templating method and functionalized with 3‐aminopropyltriethoxysilane (APTES). High porosity and aminated surface of the mesoporous silica enhance the adhesion of the particles to the PU matrix. The SEM and FTIR results showed strong interactions between the particles and the PU chains. Moreover, the thermal stability of the hybrid PUs improved compared to the pure polymer. Gas transport properties of the membranes were measured for pure CO2, CH4, O2, and N2 gases at 10 bar and 25°C. The results showed that the gas permeabilities enhanced with increasing in the loading of modified mesoporous silica particles. High porosity and amine‐functionalized particles render opportunities to enhance the gas diffusivity and solubility through the membranes. The enhanced gas transport properties of the mixed matrix membranes reveal the advantages of mesoporous silica to improve the gas permeability (CO2 permeability up to ~70) without scarifying the gas selectivity (α(CO2/N2)~ 30 for 5 wt% SBA‐16 content). [ABSTRACT FROM AUTHOR]

Core Ideas: SWIR imaging for quantification of soil moisture dynamics is introduced.High spatiotemporal resolution images yield accurate soil moisture profile.Flux density profiles during water infiltration were quantified with this method.The new technique opens potential avenues for soil hydraulic properties estimation. A novel proximal sensing framework for high‐resolution soil water content profile retrieval under laboratory conditions has been developed. Constant‐head upward‐flow experiments were conducted for a number of soils that cover a wide textural range. The soils were packed into quartz Hele–Shaw cells, and the profile was imaged at high temporal frequency with a shortwave infrared (SWIR) camera in the 900‐ to 1700‐nm electromagnetic domain during upward infiltration of water. The SWIR reflectance recorded for each spatial pixel was converted to soil water content with a recently developed linear physical model. Because of the linearity of the model, its parameters were assumed to be identical at both the pixel and column scales, and this allowed simple self‐calibration during the experiment. The obtained water content profiles were in good agreement with soil water content data measured independently with a recently developed time domain reflectometry array with 1‐cm depth resolution. In addition, the accuracy of the soil water content profiles was verified based on the water mass balance. The high‐spatiotemporal‐resolution SWIR reflectance‐derived water content profiles allow calculation of water flux densities, which provides a potential new avenue for the rapid estimation of soil hydraulic properties and processes via inverse numerical or analytical modeling. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, the melt linear viscoelastic rheological properties of polyamide 6 (PA6)-acrylonitrile butadiene styrene terpolymer (ABS) immiscible blends were analyzed with the help of Coran and fractional Zener models (FZMs) to assess the microstructure of the blends. For this purpose, dynamic shear flow experiments and scanning electron microscopy investigations were performed. The nonzero value of the elastic modulus of the spring element ( G e) of the FZM for ABS-rich blends was explained by the formation of a networklike structure because of the agglomeration of the rubber phases of the ABS matrix, whereas for the PA6-rich blends with a high content of ABS, the interactions and/or interconnectivity of the ABS dispersed phase led to a nonzero value of Ge. The value of the fitting parameter of the Coran model ( f) was near to 0.5 for the 50/50 blend; this was fully in agreement with the formed cocontinuous morphology for this blend composition. On the other hand, the f value for the blends with a matrix-droplet-type morphology was near to zero for the PA6-rich blends; this indicated the lower continuity of the ABS dispersed phase as a harder phase compared to the PA6 soft matrix, whereas the f value was near to 1 for ABS-rich blends. This confirmed the formation of an interconnected networklike structure for this series of blends. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45423. [ABSTRACT FROM AUTHOR]

Remote sensing has shown an immense capability for large-scale estimation of air temperature ( Tair), one of the most important environmental state variables, using land surface temperature ( LST) data. Following recent investigations on the Tair-LST relationship, in this article, we propose an advanced statistical approach to this realm. We tested the approach for estimation of Tair in eastern part of Iran using MODIS daytime and nighttime LST products and 11 auxiliary variables including Julian day, solar zenith angle, extraterrestrial solar radiation, latitude, altitude, reflectance at various visible and infrared bands and vegetation indices. Fourteen statistical models constructed through a stepwise regression analysis were evaluated along a 5-year period (2000-2004) using MODIS and meteorological station data. Results of this study indicated that the statistical approach performed reasonably well, where our final proposed model could estimate average Tair with validation mean absolute error of 2.3 and 1.8 °C at daily and weekly scales, respectively. Nighttime LST, Julian day, altitude and solar zenith angle indicated to be the most effective variables capturing most variations of Tair in the study region. Variables influenced by land surface and land cover properties including reflectance at different bands and vegetation indices showed a negligible effect on the Tair-LST relationship within the study area. It was indicated that the proposed models generally performed better for lower altitude regions. [ABSTRACT FROM AUTHOR]

The objective of this work was to study osmotic dehydration of banana slices using direct and indirect sonication. The optimum process was determined by response surface methodology and the effect of treatments, including mechanical agitation, indirect sonication and direct sonication, on banana microstructure was analyzed by scanning electron microscopy. Optimization of process in terms of maximum water loss and minimum solid gain, color and surface area changes was performed, and the direct sonication in sucrose concentration of 53.95% (w/v) had the best performance. Microstructure studies proved that ultrasound was responsible for creation of microchannels through the cell distortion and disconnection between cavities. Moreover, effective diffusivity for solid and water diffusion increased by 1,342.1% and 1,184.5% for direct sonication and 229.0% and 294.7% for indirect sonication for sucrose concentration 60% (w/v), respectively. Ultrasound led to increase of porosity by about 21.38% and 36.47% for indirect and direct sonication, respectively, in comparison with untreated sample. Practical Applications Drying is an expensive and energy intensive process needing long-time operation. Indirect ultrasound-assisted osmotic dehydration was previously used to enhance drying efficiency. In this article, direct ultrasound was applied to dehydrate banana slices. The results indicated that this method is very powerful, which could increase effective diffusion up to 1,342.1%. Response surface methodology was applied to maximize water loss and minimize solid gain, color and surface area changes. Direct sonication could be recommended for dehydration of fruits and vegetables. [ABSTRACT FROM AUTHOR]

The Miller-Miller similar media theory is widely applied to characterize the spatial variability of soil hydraulic properties. For a group of soils, a distinct scaling factor is commonly assigned to each individual soil to coalesce the soil water characteristic and hydraulic conductivity functions to single curves. It is generally assumed that the Miller-Miller theory is valid as long as soils are 'similar' either with regard to their microscopic pore space geometry or the closely related macroscopic soil hydraulic functions. In this paper, it is illustrated that similarity is not the sole required condition for validity of the Miller-Miller theory. In addition, the interrelation between the soil water characteristic and the hydraulic conductivity functions considered for scaling need to be comparable. The interrelation is dependent not only on the pore space geometry, but also on solid-liquid interactions. Hence similar interrelation cannot be concluded from similarity of microscopic pore space geometry. A dimensionless parameter termed the 'joint scaling factor' was defined and applied to evaluate the soundness of the interrelation condition for 26 soils from the UNSODA database that were grouped into six classes of similar soils. Obtained results clearly reveal the crucial importance of the interrelation condition for the Miller-Miller scaling theory, which has been hidden behind the 'similarity' requirement, and contradict the general belief that Miller-Miller scaling is valid as long as soils are 'similar.' [ABSTRACT FROM AUTHOR]

A new model for prediction of the effective permeability of gases in mixed matrix membranes (MMMs), considering the effects of particle shape and the interfacial layer, is presented. The proposed model treats core filler particles and interfacial shell layers as complex particles. Moreover, the Bruggman mathematical procedure is used to improve the accuracy of the presented model for high concentrations of fillers in MMMs. Also, an appropriate uniform criterion is established to make efficient use of the new model for various experimental data to avoid the need for curve-fitting procedures. Finally, the proposed model is examined for several sets of experimental data. [ABSTRACT FROM AUTHOR]

BACKGROUND: The investigation of drying kinetics and mass transfer phenomena is important for selecting optimum operating conditions, and obtaining a high quality dried product. Two analytical models, conventional solution of the diffusion equation and the Dincer and Dost model, were used to investigate mass transfer characteristics during combined microwave-convective drying of lemon slices. Air temperatures of 50, 55 and 60 °C, and specific microwave powers of 0.97 and 2.04 W g−1 were the process variables. RESULTS: Kinetics curves for drying indicated one constant rate period followed by one falling rate period in convective and microwave drying methods, and only one falling rate period with the exception of a very short accelerating period at the beginning of microwave-convective treatments. Applying the conventional method, the effective moisture diffusivity varied from 2.4 × 10−11 to 1.2 × 10−9 m2 s−1. The Biot number, the moisture transfer coefficient, and the moisture diffusivity, respectively in the ranges of 0.2 to 3.0 (indicating simultaneous internal and external mass transfer control), 3.7 × 10−8 to 4.3 × 10−6 m s−1, and 2.2 × 10−10 to 4.2 × 10−9 m2 s−1 were also determined using the Dincer and Dost model. CONCLUSIONS: The higher degree of prediction accuracy was achieved by using the Dincer and Dost model for all treatments. Therefore, this model could be applied as an effective tool for predicting mass transfer characteristics during the drying of lemon slices. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Evaporation from soil and other porous media constitutes a significant source of water loss affecting global water balance and energy exchange between land and atmosphere. The presence of a shallow water table can lead to sustained water loss that is dependent on porous media hydraulic properties and water table depth among other factors. In this paper, an exact analytical solution to steady state evaporation from porous media is developed using the Brooks-Corey hydraulic conductivity model. The solution is presented in terms of a set of infinite series. An advantage of this solution compared to previous derivations is that the infinite series can be very closely approximated using a closed-form solution (i.e., excluding integrals or series). The novel solution shows excellent agreement with the exact solution for a broad range of soil texture from sand to clay. The applicability of the solution to predict the location of the drying front was also verified using experimental data taken from the literature. The solution may be used for directly modeling steady state evaporation or for inverse determination of the Brooks-Corey hydraulic parameters. [ABSTRACT FROM AUTHOR]

ABSTRACT Impact forces during the contact are the main sources of damage in Peach fruit. In order to reduce this damage, it is necessary to model the impact forces during handling and transporting. An experimental procedure was conducted to determine the parameters of a viscoelastic normal contact force model. Peaches were subjected to dynamic loading by means of a pendulum at the levels of impact. In order to estimate the values of the parameters (spring, 'k' and damping, 'c') of the Kuwabara and Kono viscoelastic contact force models for normal impacts the nonlinear least squares technique to be calculated. Two prediction models were constructed for the parameters 'k' and 'c' using multiple linear regression analyses. In these models, impact velocity and two fruit properties (the effective radius of curvature and acoustic stiffness) were used as independent variables. Significant effect of impact velocity, the effective radius of curvature and acoustic stiffness and some interactions on the parameters 'k' and 'c' were obtained at 5% probability level with the coefficient of determination of 0.99 for models. It was concluded that lowering the impact velocity and increasing the effective radius of curvature and acoustic stiffness will enhance the parameters 'k' and 'c' of the peach fruit, but there was no significant effect of the acoustic stiffness on the damping parameter. PRACTICAL APPLICATIONS A very promising approach for the simulation of fruit impact damage during transport and handling is the contact force discrete element method (DEM). In order to do so, models for the forces acting between particles (like fruits) in contact need to be specified. Forces acting between the two particles are decomposed into normal and tangential components. In this paper the focus is set on normal contacts. The presented research determines the parameters of normal contact forces models suited for DEM simulation of viscoelastic materials (peach fruit). [ABSTRACT FROM AUTHOR]

This article presents a novel computer‐aided prediction system based on integration of fixed‐grid wavelet network (FGWN) and image processing technique for quantification of pigments (chlorophyll and carotenoid contents) in bitter orange peel. The proposed intelligent system captures the fruits image and uses image processing followed by principal component analysis (PCA) in order to extract the effective features. They consisted of 34 color features in the RGB and CIE color spaces, including some statistical parameters of color matrices (R, G, and B) or their differences and ratios as well as three CIE parameters. The first four principal components of the selected features are then fed as the inputs to the FGWN for estimating each pigment. The chlorophyll and carotenoid contents were modeled with the acceptable determination coefficient of 0.96 and 0.87, respectively. To evaluate the performance of the WN, it is compared against two common and powerful artificial intelligence techniques namely artificial neural network (ANN) and adaptive neuro‐fuzzy inference system (ANFIS). The results revealed that the WN could provide almost the same performance with a much lower number of parameters. Therefore, this study develops a novel attempt of strategy to be used for quality control of the bitter orange peel. Practical applications: A research challenge could be developing a fast, cheap, and nondestructive system that predicts pigments contents of citrus fruits for different applications and/or specifying the necessity of postharvest artificial de‐greening to satisfy market demand. The integration of image processing and fixed‐grid wavelet network (FGWN) is a potential approach to overcome the mentioned challenge. Such an integration showed acceptable results for the determination of chlorophylls and carotenoids content in bitter oranges in the current study. In terms of applicability, the parsimonious models of the FGWN is quite desirable for online uses. [ABSTRACT FROM AUTHOR]

Poly(ether sulfone) (PES), because of its low chain mobility and high gas selectivity, was selected as a gas‐separation membrane. Because poly(ethylene glycol) (PEG) contains polar ether groups favorable for carbon dioxide (CO2) capture, we investigated the effects of PEG on the CO2/CH4 and CO2/N2 separation properties of PES–PEG blend membranes. PEG with different molecular weights (4000, 6000, and 10,000) and concentrations of up 30 wt % was added to PES. Scanning electron microscopy and wide‐angle X‐ray diffraction analyses on the blends confirmed the uniformity and dense surfaces of the membranes and no changes in the crystallinity, respectively. Fourier transform infrared spectra indicated good interactions between the PEG and PES segments. Gas permeation tests showed that with increasing PEG molecular weight, its weight fraction permeability of CH4 and CO2 increased, whereas the permeability of O2 and N2 decreased. The best composition of PES–PEG was a 70/30 ratio; with this composition, the selectivities of CO2/N2 and CO2/CH4 were enhanced by 64 and 14%, respectively, compared to that of the pure membrane. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46845. [ABSTRACT FROM AUTHOR]

Near-surface soil conditions (i.e., moisture and temperature) moderate mass and energy exchange at the soil-atmosphere interface. While remote sensing offers an effective means for mapping near-surface moisture content across large areas, in situ measurements, targeting those specific remotely sensed soil depths, are poorly understood and high-resolution near-surface measurement capabilities are lacking. Time domain reflectometry (TDR) is a well-established, accurate measurement method for soil dielectric permittivity and moisture content. A TDR array was designed to provide centimeter-resolution measurements of near-surface soil moisture. The array consists of nine stainless steel TDR rods spaced 1 cm apart, acting as waveguide pairs to form eight two-rod TDR probes in series. A critical aspect of the design was matching the spacing of the coaxial cable-TDR rod transition to avoid unwanted reflections in the waveforms. The accuracy of the TDR array permittivity measurement (±1 permittivity unit) was similar to that of conventional TDR as verified in dielectric liquids. Electric field numerical simulations showed minimal influence of adjacent rods during a given rod-pair measurement. The evaporation rate determined by the TDR array compared well with mass balance data in a laboratory test. Near-surface soil moisture profile dynamics were monitored at centimeter-depth resolution using the TDR array in a field experiment where volumetric moisture content estimates (0-8 cm) were within 2% of conventional three-rod TDR probes averaging across 0 to 8 cm and from 1- to 3-cm depths. [ABSTRACT FROM AUTHOR]

A novel method for scaling water flow and solute transport during soil-water redistribution was developed. The scaled results are invariant for a broad range of soil textures and initial conditions. The scaling method gives insight regarding transport processes and provides an approximate solution of the highly non-linear governing equations. A recently developed method for scaling Richards' equation during soil-water redistribution was extended here to derive invariant solutions for solute transport for a range of soils and initial conditions. Any arbitrary model for hydraulic properties can be used in Richards' equation. A transport model including both terms of convection and diffusion/dispersion is considered where the soil-solute reactions described by a linear sorption isotherm are considered. To evaluate the proposed method, Hydrus-1D simulations were used to solve the water flow and solute transport equations for various soil textures and initial conditions. The resulting soil water content and solute concentrations profiles were scaled using the proposed method. The scaled results were nearly invariant for loam to clay soil textures and for a variety of initial conditions. The invariance of the scaled results implies a robust approach to scaling water flow and solute transport during the redistribution process and readily produces approximate solutions of the highly nonlinear governing equations. [ABSTRACT FROM AUTHOR]