Shrinkage of Mirabelle Plum during Hot Air Drying as Influenced by Ultrasound-Assisted Osmotic Dehydration

Convective drying in hot air is still the most popular method applied to reduce the moisture content of fruits and vegetables. Conventional hot-air drying of Mirabelle plum is considered to be a slow and energy intensive process. This is due to the fact that the waxy skin of Mirabelle plum has low permeability to moisture, a fact which results in high shrinkage. The aim of this study was to investigate the effect of ultrasound-assisted osmotic dehydration pretreatment on shrinkage of Mirabelle plum as a function of moisture content with the end goal of optimizing operating conditions that minimize shrinkage of the produce during drying. Results showed that application of ultrasound-assisted osmotic dehydration led to a significant (p < 0.05) decrease in shrinkage (from 76.41 to 64.05%). A linear relation between moisture loss and shrinkage was observed. Results indicated that shrinkage may be easily estimated from changes in moisture content, and independent of the drying rate. Inversely, determination of shrinkage would provide an indirect indication of moisture content.     

A case study on the assessment of response modification coefficient and earthquake-induced collapse potential of a high-rise setback tower

This paper evaluates response modification coefficient (R-factor) and collapse potential of a high-rise tower with setback irregularity under spectral-matched ground motion records. The tower is comprised of two legs with three distinct lateral bearing systems in elevation and curved configuration in plan. Furthermore, it has a setback in elevation, recognised by inclined columns joining two legs of the tower in uppermost stories. These characteristics cause the tower to classify as a complex irregular structure in which using code-based R-factor is highly dubious. In this paper, initially, an analytical model of the tower was subjected to a suite of ground motions to estimate collapse potential and equivalent R-factor in accordance with FEMA P695. Alternatively, structural performance parameters including inter-storey drift ratios, residual drift ratios and plastic hinge rotations were compared to TBI acceptance criteria. To achieve consistent safety margin against collapse, the value of 8 was suitable for R-factor. In spite of satisfactory threshold in accordance with FEMA P695 and TBI guidelines, for a structure with irregular configuration and multiple bearing system, damages can be localised close to zones of change in lateral bearing system that may lead to partial collapse.     

Application of MLP-ANN as novel tool for estimation of effect of inhibitors on asphaltene precipitation reduction

Sedimentation of heavy fractions of oil such as asphaltene is the main concern in different parts of petroleum industries like production and transportation. Due to this fact, the inhibition of asphaltene precipitation becomes one of the great interests in the petroleum industry. In the present investigation, multi-layer perceptron artificial neural network (MLP-ANN) was developed to estimate asphaltene precipitation reduction as a function of concentration and kind of inhibitors and oil properties. To this end, a total number of 75 data points were extracted from reliable source for training and validation of predicting algorithm. The outputs of MLP-ANN were compared with experimental data graphically and statistically, the determined coefficients of determination (R²) for training and testing are 0.996522 and 0.995239 respectively. These comparisons expressed the high quality of this algorithm in the prediction of asphaltene precipitation reduction. so the MLP-ANN can be used as a powerful machine for estimation of different processes in petroleum industries.     

Modified low molecular weight acrylics in coating application: synthesis and property evaluation

Low molecular weight resins containing relatively high levels of acrylic acid were converted to oxidatively curable materials by reacting the carboxylic acid groups with oxazoline functional alkenes. The oxazolines were obtained by reacting fatty acid with 2-amino-2-methyl-1-propanol. The oxazolines were then reacted with the acrylic resins at elevated temperature. Relatively high yields of the desired reaction products were obtained in relatively short reaction times. The resulting resins were formulated into aqueous coatings and films were made over metal substrates. The films were cured oxidatively and evaluated for property development. The films had good general solvent resistance but poor resistance to dilute sodium hydroxide.

Bit Selection Optimization Using Artificial Intelligence Systems

Abstract

Optimizing bit selection is one of the main challenges in drilling operations. Bit selection is based on the recorded performance of similar bits from offset wells. There are too many parameters intervening in drilling bit selection. Therefore, developing a logical relationship between them to assist in proper bit selection is extremely necessary and complicated though. In such a case, artificial neural networks (ANNs) have proven to be helpful in recognizing the complex relationship between variables. In this new approach, two models are developed with high proficiency using ANNs. The first model provides appropriate drilling bit selection based on the desired rate of penetration (ROP) to be obtained by applying specific drilling parameters. The second model uses proper drilling parameters obtained from an optimizing procedure to select the drilling bit that provides the maximum achievable rate of penetration. Genetic algorithms (GAs), as a class of optimizing methods for complex functions, are applied to help bit optimization and its related drilling parameters. With the given data sets, these new models predicted successfully the bit types and the optimum drilling parameters. The correlation coefficients for the predicted bit types and optimum drilling parameters in testing the obtained networks are 0.96 and 0.86, respectively. MATLAB software was used to perform ANN and GA solutions.     

Chemically crosslinked polyvinyl alcohol for water shut-off and conformance control treatments during oil production: The effect of silica nanoparticles

Polyvinyl alcohol (PVA) is a synthetic commercial polymer with the inherent hydrophilicity, thermal and chemical resistance, ecofriendly, and a high anti-fouling potential making it an attractive choice for water treatment applications, but has been less studied for oil and gas industry applications. On the other hands, nowadays nanotechnology has gained an important space within most core areas in upstream oil and gas operations. The present work, first PVA at various concentrations, was added to 5 wt% NaCl solution and then, crosslinked by formaldehyde 37% at two different concentration ratios. To compare, a nanocomposite hydrogel was fabricated in the same way with 1 wt% silica nanoparticles (NPs). Contact angle and filtration test were performed to confirm the ability of PVA hydrogel and nanocomposite hydrogel for oil and water adsorption. Following this, a rheology measurement was made to realize the gelation time of samples and their performance for water shutoff applications. Finally, an experimental flooding setup was designed to inject the fluids into carbonate plugs in order to estimate of oil and water effective permeability, and oil recovery factor (RF) before and after the PVA hydrogel and nanocomposite hydrogel injection. Both samples wettability tests showed a super-hydrophilic state for brine droplets and neutral state for synthetic oil droplets by using nanocomposite hydrogel. The flooding tests revealed that the PVA hydrogel was clogged the plug with blocking efficiency of 32.83% for water effective permeability and 14.60% for oil effective permeability. This value was calculated to be 50.37% for water effective permeability and 31.36% for oil effective permeability in the case of nanocomposite hydrogel injection. Oil RF was also reported to be 64.58% after injecting PVA hydrogel which was higher than nanocomposite hydrogel injection with RF of 52.08%.     

Innovative Diagnostic Peptide-Based Technologies for Cancer Diagnosis: Focus on EGFR-Targeting Peptides

Active targeting using biological ligands has emerged as a novel strategy for the targeted delivery of diagnostic agents to tumor cells. Conjugating functional targeting moieties with diagnostic probes can increase their accumulation in tumor cells and tissues, enhancing signal detection and, thus, the sensitivity of diagnosis. Due to their small size, ease of chemical synthesis and site-specific modification, high tissue penetration, low immunogenicity, rapid blood clearance, low cost, and biosafety, peptides offer several advantages over antibodies and proteins in diagnostic applications. Epidermal growth factor receptor (EGFR) is one of the most promising cancer biomarkers for actively targeting diagnostic and therapeutic agents to tumor cells due to its active involvement and overexpression in various cancers. Several peptides for EGFR-targeting have been identified in the last decades, which have been obtained by multiple means including derivation from natural proteins, phage display screening, positional scanning synthetic combinatorial library, and in silico screening. Many studies have used these peptides as a targeting moiety for diagnosing different cancers in vitro, in vivo, and in clinical trials. This review summarizes the progress of EGFR-targeting peptide-based assays in the molecular diagnosis of cancer.     

Magnetic Resonance Imaging of Tumor-Infiltrating Lymphocytes by Anti-CD3-Conjugated Iron Oxide Nanoparticles

Immune checkpoint blockade, considered a revolutionary approach in cancer treatment, is only effective in patients with high tumor-infiltrating lymphocytes (TILs). This work aimed to investigate the feasibility of targeted contrast agent (CA) based on dextran-coated superparamagnetic iron oxide nanoparticles (SPIONs-DEX) for TILs detection by magnetic resonance imaging (MRI) studies. To do so, we synthesized an MRI CA by conjugating SPIONs-DEX to an anti-CD3 monoclonal antibody via cyanogen bromide as a cross-linker. In vitro assessments demonstrated the higher labeling efficiency of the developed CA to CD3+ lymphocytes compared to SPIONs-DEX. In vivo MRI of a xenograft model of CD3+ lymphocytes revealed the significant signal loss after the intravenous injection of the bioconjugate by ∼34 % and 21 % in T₂*-weighted and T₂-weighted images, respectively. The histopathological evaluation of xenograft tumors confirmed the labeling of lymphocytes by the targeted CA. This approach could open up a new horizon in the non-invasive assessment of TILs to identify patients eligible for immunotherapy.     

Biodegradable composite films based on Trigonella foenum-graceum galactomannan—xanthan gum: Effect of grape seed oil on various aspects of emulsified films

Nowadays, preparing biodegradable films based on hydrocolloids has become thoroughly crucial in food packaging. Also, to enhance some of the aspects of these films, adding oil to the formulation of the films has been considered as a valid method. In this study, a variety of films based on two biopolymers (fenugreek galactomannan and xanthan gum) in the presence or absence of grape seed oil were produced and the various aspects of the obtained films were comprehensively investigated. The obtained data demonstrated that preparing composite films based on two hydrocolloids improved the aspects including film thickness, water vapor permeability (WVP), oxygen permeability (OP), mechanical and thermal properties more than films based on only one hydrocolloid. This improvement was mostly related to the good and acceptable interaction between two biopolymers. The X-ray diffraction (XRD) patterns indicated that all films had an amorphous or non-crystalline structure. Also, the scanning electron microscope images demonstrated that films based on fenugreek galactomannan and composite films based on two hydrocolloids. The value of film thickness and strain at break (SAB) increased by adding oil to the formulation. Contrarily, the moisture content and absorption, WVP, OP, opacity, and ultimate tensile strength (UTS) values of the films decreased by adding oil.     

Cover Image

Hollow structural section (HSS) and concrete-filled tube (CFT) cross-sections have been widely employed in the columns and braces of special concentrically braced frames (SCBFs). Square-HSS cross-section widely used in multistory frames is filled with concrete and converted to square-CFT cross-section to enhance the behavior of this cross-section. However, some investigations indicated that circular-HSS cross-section filled with concrete (circular-CFT) showed better behavior in comparison with square-CFT cross-section due to more uniform and larger concrete confinement in circular-CFT cross-section. The current study was experimentally undertaken to evaluate (1) the seismic performance and the global and local hysteresis responses of HSS and CFT members with various cross-section shapes from initial elastic range to collapse in the system level of multistory SCBFs, (2) the behavioral differences between square cross-section and circular cross-section, and (3) the behavioral differences between HSS cross-sections and CFT cross-sections employed in the columns and braces of SCBFs. Four full-scale one-bay, two-story SCBFs with four various cross-sections, namely, square-HSS, circular-HSS, square-CFT, and circular-CFT, for columns and braces were subjected to cyclic lateral loading. Evaluating base shear–roof drift hysteretic loops of SCBF specimens demonstrated that SCBF specimens with CFT columns and braces (CFT-SCBFs) experienced respectively around 107%, 58%, 28%, and 152% higher stiffness, post-yielding and post-buckling strengths, ductility, and energy dissipation capacity than SCBF specimens with HSS columns and braces (HSS-SCBF). In addition, the experimental observations indicated that CFT braces experienced local buckling initiation, crack initiation, and fracture at respectively 2.22, 2.35, and 2.32 times of roof drifts of those exhibited by HSS braces. Moreover, assessing braces with various cross-sections indicated that CFT braces showed an increase in compression strength, post-buckling strength, compression axial deformation, and out-of-plane buckling approximately by 83%, 152%, 127%, and 100%, respectively, in comparison with HSS braces. Finally, square-HSS/CFT braces sustained rupture propagation better than circular-HSS/CFT braces.