bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Various Binders on the Properties of Microalgae-Enriched Urea Granules
Authors: Mikolaitienė Austėja , Šlinkšienė Rasa
Published: December 2022

As the human population grows and the demand for food grows with it, the recycling, or containment of materials is important for resource consumption. Nitrogen is one of the main plant nutrients, most commonly used as the chemical substance urea. Because urea is very soluble and at a relatively low temperature (50–60 °C) it hydrolyses easily (releases N2 and CO2) in soil solutions; this is why very large amounts of nitrogen are lost and greenhouse gases are released and this causes serious environmental problems. Therefore, the aim of this study was to create microalgae-enriched nitrogen fertilizers with different binders that inhibit nitrogen leaching from the soil. Binders such as water (W), polyvinyl acetate dispersion (PVAD), molasses (M), potato starch (S), and carboxymethyl cellulose (CMC) were used in this study and their influence on leaching was analysed. Granular fertilizers were produced in a drum granulator and dryer under equal conditions: granulation time was 7 min, granulation took place at a temperature of 50–60 °C, at a drum rotation speed of 26 rpm, with a 5° inclination angle of the drum. The results show that the highest quantity of the marketable fraction was 43.01 (±3.068%) and it was obtained using urea, with 10% (w/w) microalgae additive, and 11.4% (w/w) of 5% concentration molasses solution. The granules of the fertilizer marketable fraction are similar in size because the size guide number (SGN) of the granules vary in a narrow range and fall within the interval of 287 to 304; this means that the average particle size is ~3 mm. When different binders were used, the average static crushing strength of the granulated fertilizers was lower (approximately 6–12 MPa) than using water alone (approximately 12–16 MPa), but the lower values still fell into the required range. Additives of PVAD solutions and molasses solutions have been found to retain nitrogen in sand. The method of one-way analysis of variance (ANOVA) was used to evaluate the results.
Identification of microRNA158 from Anthurium andraeanum and Its Function in Cold Stress Tolerance
Authors: Jiang Li , Fu Yanxia , Sun Pan , Tian Xingkai , Wang Guangdong
Published: December 2022

Anthurium andraeanum is a tropical flower with high ornamental and economic value. Cold stress is one of the major abiotic stresses affecting the quality and value of A. andraeanum; thus, improving the cold tolerance of this species is an important breeding objective. MicroRNAs (miRNAs) have a critical role in plant abiotic stress responses, but their specific molecular regulatory mechanisms are largely unknown, including those related to the cold stress response in A. andraeanum. Here, we identified and cloned the precursor of miR158 from A. andraeanum (Aa-miR158). Both Aa-miR158 and its target gene (c48247) had higher expression levels in strong leaves than in other tissues or organs. Further study revealed that the transcript level of Aa-miR158 was increased by cold stress. Heterologous overexpression of Aa-miR158 improved cold stress tolerance in Arabidopsis, which was associated with decreases in the malondialdehyde (MDA) concentration and relative electrical conductivity (REC) as well as increases in peroxidase (POD) and catalase (CAT) activity. Moreover, overexpressing Aa-miR158 significantly increased the expression of endogenous genes related to cold stress tolerance and reactive oxygen species (ROS) levels in transgenic Arabidopsis under cold stress. Overall, our results demonstrate that Aa-miR158 is significantly involved in the cold stress response and provide a new strategy for cold tolerance breeding of A. andraeanum.
Estrogenic Activity of 4-Hydroxy-Benzoic Acid from Acer tegmentosum via Estrogen Receptor α-Dependent Signaling Pathways
Authors: Nguyen Quynh Nhu , Lee Seoung Rak , Kim Baolo , Hong Joo-Hyun , Jang Yoon Seo , Lee Da Eun , Pang Changhyun , Kang Ki Sung , Kim Ki Hyun
Published: December 2022

Acer tegmentosum, a deciduous tree belonging to Aceraceae, has been used in traditional oriental medicine for treating hepatic disorders, such as hepatitis, cirrhosis, and liver cancer. We evaluated the estrogen-like effects of A. tegmentosum using an estrogen receptor (ER)-positive breast cancer cell line, namely MCF-7, to identify potential phytoestrogens and found that an aqueous extract of A. tegmentosum promoted cell proliferation in MCF-7 cells. Five phenolic compounds (1–5) were separated and identified from the active fraction using bioassay-guided fractionation of crude A. tegmentosum extract and phytochemical analysis. The chemical structures of the compounds were characterized as vanillic acid (1), 4-hydroxy-benzoic acid (2), syringic acid (3), isoscopoletin (4), and (E)-ferulic acid (5) based on the analysis of their nuclear magnetic resonance spectra and liquid chromatography-mass spectrometry data. All five compounds were evaluated using an E-screen assay for their estrogen-like effects on MCF-7 cells. Among the tested compounds, only 4-hydroxy-benzoic acid (2) promoted the proliferation of MCF-7 cells, which was mitigated by the ER antagonist, ICI 182,780. The mechanism underlying the estrogen-like effect of 4-hydroxy-benzoic acid (2) was evaluated via western blotting analysis to determine the expression levels of extracellular signal-regulated kinase (ERK), phosphoinositide 3-kinase (PI3K), serine/threonine kinase (AKT), and ERα. Our results demonstrated that 4-hydroxy-benzoic acid (2) induced the increase in the protein expression levels of p-ERK, p-AKT, p-PI3K, and p-Erα, concentration dependently. Collectively, these experimental results suggest that 4-hydroxy-benzoic acid (2) is responsible for the estrogen-like effects of A. tegmentosum and may potentially aid in the control of estrogenic effects during menopause.
Reckoning Groundwater Quality and Hydrogeochemical Processes for Drinking and Irrigation Purposes under the Influence of Anthropogenic Activities, North India
Authors: Ahmed Salman , Mulhim Mohammad , Qureshi Fazil , Akhtar Naseem , Lagudu Surinaidu
Published: December 2022

The present study was carried out near an industrial area with a high-density urban population and large-scale agricultural activities. These anthropogenic activities lead to groundwater pollution and depletion of the water table. This study attempted to classify pollution sources and hydrochemical facies that help to ensure the suitability of water for agriculture and drinking. Irrigation suitability indexes, water quality index (WQI), principal component analysis (PCA), and hierarchical cluster analysis (HCA) were applied to twenty-six groundwater samples that were analysed during May 2018 for major cations and anion concentrations. The results revealed that the mechanism of groundwater chemistry has been controlled by the evaporation process with the dominance of hydrochemical facies viz., Ca-Mg-HCO3, Na-K-Cl-SO4, Ca-Mg-Cl, and Na-K-HCO3. The mean dominant concentration for cations is in the order of Ca2+ > Na+ > Mg2+ > K+ while anions are HCO3− > SO4− > Cl− > NO3− > CO32− > F−. Irrigation suitability indexes indicated that groundwater in the study area is high in saline and low to medium alkali hazards due to industrial activities. The PCA and HCA also recognized that most of the variations are elucidated by anthropogenic processes, predominantly due to excessive population, industrial emissions, and agricultural activities. Further, the WQI of the study area suggested that 15% of the samples were unsuitable, 69% poor, and the remaining 16% only suitable for drinking purposes. The present article helps to understand the suitability and hydrochemical processes of groundwater for irrigation and drinking, which will help policymakers in water supply planning and management.
Photocurable 3D-Printable Systems with Controlled Porosity towards CO2 Air Filtering Applications
Authors: Chiappone Annalisa , Pedico Alessandro , Porcu Stefania , Pirri Candido Fabrizio , Lamberti Andrea , Roppolo Ignazio
Published: December 2022

Porous organic polymers are versatile platforms, easily adaptable to a wide range of applications, from air filtering to energy devices. Their fabrication via vat photopolymerization enables them to control the geometry on a multiscale level, obtaining hierarchical porosity with enhanced surface-to-volume ratio. In this work, a photocurable ink based on 1,6 Hexanediol diacrylate and containing a high internal phase emulsion (HIPE) is presented, employing PLURONIC F-127 as a surfactant to generate stable micelles. Different parameters were studied to assess the effects on the morphology of the pores, the printability and the mechanical properties. The tests performed demonstrates that only water-in-oil emulsions were suitable for 3D printing. Afterwards, 3D complex porous objects were printed with a Digital Light Processing (DLP) system. Structures with large, interconnected, homogeneous porosity were fabricated with high printing precision (300 µm) and shape fidelity, due to the addition of a Radical Scavenger and a UV Absorber that improved the 3D printing process. The formulations were then used to build scaffolds with complex architecture to test its application as a filter for CO2 absorption and trapping from environmental air. This was obtained by surface decoration with NaOH nanoparticles. Depending on the surface coverage, tested specimens demonstrated long-lasting absorption efficiency.
Use of Cement Mortar Incorporating Superabsorbent Polymer as a Passive Fire-Protective Layer
Authors: Jamnam Sittisak , Sua-iam Gritsada , Maho Buchit , Pianfuengfoo Satharat , Sappakittipakorn Manote , Zhang Hexin , Limkatanyu Suchart , Sukontasukkul Piti
Published: December 2022

Concrete structures, when exposed to fire or high temperatures for a certain time, could suffer partial damage or complete structural failure. Passive fire-protective coating materials are an alternative way to prevent or delay damage to concrete structures resulting from fire. Superabsorbent polymer (SP) is a synthetic material known for its ability to absorb and retain a large volume of water within itself. With this unique property, the SP exhibits great potential for use as a passive fire protection material. Although several studies have been carried out to investigate the effect of SP as a surface coating material for fire protection, very few have been investigated on the potential use of SP mixed with mortar as a passive fire-protective layer. The objective of this study is to introduce the use of SP in plastering mortar as a fire-protective layer for concrete subjected to temperatures up to 800 °C. This study is divided into two parts: (1) investigating the properties of cement mortar mixed with SP at 0.5% (CONC/SP-0.5) and 1.0% (CONC/SP-1.0) by weight of cement, and (2) investigating the potential use of SP mortar as a plastering layer for concrete subject to high temperatures. The experimental results showed that the density and compressive strength of SP mortar decreases with increasing SP dosages. From the heat exposure results, SP mortar exhibited lower strength loss due to the ability to mitigate moisture through its interconnected pore system. As for the use of SP mortar as a plastering layer, the results demonstrated the concrete specimen plastered with SP mortar had a lower temperature at the interface and core than that plastered with plain mortar. This led to a reduced strength loss of 20.5% for CONC/SP-0.5 and 17.2% for CONC/SP-1.0.
Green Copolymers and Nanocomposites from Myrcene and Limonene Using Algerian Nano-Clay as Nano-Reinforcing Filler
Authors: Derdar Hodhaifa , Mitchell Geoffrey Robert , Mateus Artur , Chaibedraa Sarra , Elabed Zinelabidine Otmane , Mahendra Vidhura Subash , Cherifi Zakaria , Bachari Khaldoun , Chebout Redouane , Meghabar Rachid , Harrane Amine , Belbachir Mohammed
Published: December 2022

In this work, we report a new facile method for the preparation of myrcene-limonene copolymers and nanocomposites using a Lewis acid as a catalyst (AlCl3) and organo-modified clay as a nano-reinforcing filler. The copolymer (myr-co-lim) was prepared by cationic copolymerization using AlCl3 as a catalyst. The structure of the obtained copolymer is studied and confirmed by Fourier Transform Infrared spectroscopy, Nuclear Magnetic Resonance spectroscopy, and Differential Scanning Calorimetry. By improving the dispersion of the matrix polymer in sheets of the organoclay, Maghnite-CTA+ (Mag-CTA+), an Algerian natural organophilic clay, was used to preparenanocomposites of linear copolymer (myr-co-lim). In order to identify and assess their structural, morphological, and thermal properties, the effect of the organoclay, used in varyingamounts (1, 4, 7, and 10% by weight), and the preparation process were investigated. The Mag-CTA+ is an organophylic montmorillonite silicate clay prepared through a direct exchange process in which they were used as green nano-reinforcing filler. The X-ray diffraction of the resulting nanocomposites revealed a considerable alteration in the interlayer spacing of Mag-CTA+. As a result, interlayer expansion and myr-co-lim exfoliation between layers of Mag-CTA+ were observed. Thermogravimetric analysis provided information on the synthesized nanocomposites’ thermal properties. Fourier transform infrared spectroscopy and scanning electronic microscopy, respectively, were used to determine the structure and morphology of the produced nanocomposites (myr-co-lim/Mag). The intercalation of myr-co-lim in the Mag-CTA+ sheets has been supported by the results, and the optimum amount of organoclay needed to create a nanocomposite with high thermal stability is 10% by weight. Finally, a new method for the preparation of copolymer and nanocomposites from myrcene and limonene in a short reaction time was developed.
Effect of Micro- and Nano-Lignin on the Thermal, Mechanical, and Antioxidant Properties of Biobased PLA–Lignin Composite Films
Authors: Makri Sofia P. , Xanthopoulou Eleftheria , Klonos Panagiotis A. , Grigoropoulos Alexios , Kyritsis Apostolos , Tsachouridis Konstantinos , Anastasiou Antonios , Deligkiozi Ioanna , Nikolaidis Nikolaos , Bikiaris Dimitrios N.
Published: December 2022

Bio-based poly(lactic acid) (PLA) composite films were produced using unmodified soda micro- or nano-lignin as a green filler at four different contents, between 0.5 wt% and 5 wt%. The PLA–lignin composite polymers were synthesized by solvent casting to prepare a masterbatch, followed by melt mixing. The composites were then converted into films, to evaluate the effect of lignin content and size on their physicochemical and mechanical properties. Differential scanning calorimetry (DSC), supported by polarized light microscopy (PLM), infrared spectroscopy (FTIR-ATR), X-ray diffraction (XRD), and transmission electron microscopy (TEM) were employed to investigate the PLA crystallization and the interactions with Lignin (L) and Nanolignin (NL). The presence of both fillers (L and NL) had a negligible effect on the glass transition temperature (chain diffusion). However, it resulted in suppression of the corresponding change in heat capacity. This was indicative of a partial immobilization of the PLA chains on the lignin entities, due to interfacial interactions, which was slightly stronger in the case of NL. Lignin was also found to facilitate crystallization, in terms of nucleation; whereas, this was not clear in the crystalline fraction. The addition of L and NL led to systematically larger crystallites compared with neat PLA, which, combined with the higher melting temperature, provided indications of a denser crystal structure in the composites. The mechanical, optical, antioxidant, and surface properties of the composite films were also investigated. The tensile strength and Young’s modulus were improved by the addition of L and especially NL. The UV-blocking and antioxidant properties of the composite films were also enhanced, especially at higher filler contents. Importantly, the PLA–NL composite films constantly outperformed their PLA–L counterparts, due to the finer dispersion of NL in the PLA matrix, as verified by the TEM micrographs. These results suggest that bio-based and biodegradable PLA films filled with L, and particularly NL, can be employed as competitive and green alternatives in the food packaging industry.
Thermo-Mechanical and Creep Behaviour of Polylactic Acid/Thermoplastic Polyurethane Blends
Authors: Jhao Yi-Sheng , Ouyang Hao , Yang Fuqian , Lee Sanboh
Published: December 2022

There is a great need to develop biodegradable thermoplastics for a variety of applications in a wide range of temperatures. In this work, we prepare polymer blends from polylactic acid (PLA) and thermoplastic polyurethane (TPU) via a melting blend method at 200 °C and study the creep deformation of the PLA/TPU blends in a temperature range of 10 to 40 °C with the focus on transient and steady-state creep. The stress exponent for the power law description of the steady state creep of PLA/TPU blends decreases linearly with the increase of the mass fraction of TPU from 1.73 for the PLA to 1.17 for the TPU. The activation energies of the rate processes for the steady-state creep and transient creep decrease linearly with the increase of the mass fraction of TPU from 97.7 ± 3.9 kJ/mol and 59.4 ± 2.9 kJ/mol for the PLA to 26.3 ± 1.3 kJ/mol and 25.4 ± 1.7 kJ/mol for the TPU, respectively. These linearly decreasing trends can be attributed to the weak interaction between the PLA and the TPU. The creep deformation of the PLA/TPU blends consists of the contributions of individual PLA and TPU.
Acrylic Resin Filling Cell Lumen Enabled Laminated Poplar Veneer Lumber as Structural Building Material
Authors: Gao Xudong , Liu Yiliang , Qi Yanran , Gong Ruizhi , Yao Fengbiao , Luo Jiajia , Zhao Yueying , Dai Yong , Wang Jinguo , Lian Chenglong , Dong Xiaoying , Li Yongfeng
Published: December 2022

Wood is a viable alternative to traditional steel, cement, and concrete as a structural material for building applications, utilizing renewable resources and addressing the challenges of high energy consumption and environmental pollution in the construction industry. However, the vast supply of fast-growing poplar wood has bottlenecks in terms of low strength and dimensional stability, making it difficult to use as a structural material. An environmentally friendly acrylic resin system was designed and cured in this study to fill the poplar cell cavities, resulting in a new type of poplar laminated veneer lumber with improved mechanical strength and dimensional stability. The optimized acrylic resin system had a solid content of 25% and a curing agent content of 10% of the resin solid content. The cured filled poplar veneer gained 81.36% of its weight and had a density of 0.69 g/cm3. The static flexural strength and modulus of elasticity of the further prepared laminated veneer lumber were 123.12 MPa and 12,944.76 MPa, respectively, exceeding the highest flexural strength required for wood structural timber for construction (modulus of elasticity 12,500 MPa and static flexural strength 35 MPa). Its tensile strength, impact toughness, hardness, attrition value, water absorption, water absorption thickness expansion, and water absorption width expansion were 58.81%, 19.50%, 419.18%, 76.83%, 44.38%, 13.90%, and 37.60% higher than untreated laminated veneer lumber, demonstrating improved mechanical strength and dimensional stability, significantly. This method provides a novel approach to encouraging the use of low-value-added poplar wood in high-value-added structural building material applications.
Green and Sustainable Hot Melt Adhesive (HMA) Based on Polyhydroxyalkanoate (PHA) and Silanized Cellulose Nanofibers (SCNFs)
Authors: Jo Jaemin , Jeong So-Yeon , Lee Junhyeok , Park Chulhwan , Koo Bonwook
Published: December 2022

Polyhydroxyalkanoate (PHA), with a long chain length and high poly(4–hydroxybutyric acid) (P4HB) ratio, can be used as a base polymer for eco-friendly and biodegradable adhesives owing to its high elasticity, elongation at break, flexibility, and processability; however, its molecular structures must be adjusted for adhesive applications. In this study, surface-modified cellulose nanofibers (CNFs) were used as a hydrophobic additive for the PHA-based adhesive. For the surface modification of CNFs, double silanization using tetraethyl orthosilicate (TEOS) and methyltrimethoxysilane (MTMS) was performed, and the thermal and structural properties were evaluated. The hydrophobicity of the TEOS- and MTMS-treated CNFs (TMCNFs) was confirmed by FT-IR and water contact angle analysis, with hydrophobic CNFs well dispersed in the PHA. The PHA–CNFs composite was prepared with TMCNFs, and its morphological analysis verified the good dispersion of TMCNFs in the PHA. The tensile strength of the composite was enhanced when 10% TMCNFs were added; however, the viscosity decreased as the TMCNFs acted as a thixotropic agent. Adding TMCNFs to PHA enhanced the flowability and infiltration ability of the PHA–TMCNFs-based adhesive, and an increase in the loss tangent (Tan δ) and adjustment of viscosity without reducing the adhesive strength was also observed. These changes in properties can improve the flowability and dispersibility of the PHA–TMCNFs adhesive on a rough adhesive surface at low stress. Thus, it is expected that double-silanized CNFs effectively improve their interfacial adhesion in PHA and the adhesive properties of the PHA–CNFs composites, which can be utilized for more suitable adhesive applications.
Natural Coatings and Surface Modifications on Magnesium Alloys for Biomedical Applications
Authors: Cuartas-Marulanda Diego , Forero Cardozo Laura , Restrepo-Osorio Adriana , Fernández-Morales Patricia
Published: December 2022

Magnesium (Mg) alloys have great potential in biomedical applications due to their incomparable properties regarding other metals, such as stainless steels, Co–Cr alloys, and titanium (Ti) alloys. However, when Mg engages with body fluids, its degradation rate increases, inhibiting the complete healing of bone tissue. For this reason, it has been necessary to implement protective coatings to control the rate of degradation. This review focuses on natural biopolymer coatings used on Mg alloys for resorbable biomedical applications, as well as some modification techniques implemented before applying natural polymer coatings to improve their performance. Issues such as improving the corrosion resistance, cell adhesion, proliferation, and biodegradability of natural biopolymers are discussed through their basic comparison with inorganic-type coatings. Emphasis is placed on the expected biological behavior of each natural polymer described, to provide basic information as a reference on this topic.
Novel Non-Viral Vectors Based on Pluronic® F68PEI with Application in Oncology Field
Authors: Silva Inês , Domingues Cátia , Jarak Ivana , Carvalho Rui A. , Cordeiro Rosemeyre A. , Dourado Marília , Veiga Francisco , Faneca Henrique , Figueiras Ana
Published: December 2022

Copolymers composed of low-molecular-weight polyethylenimine (PEI) and amphiphilic Pluronics® are safe and efficient non-viral vectors for pDNA transfection. A variety of Pluronic® properties provides a base for tailoring transfection efficacy in combination with the unique biological activity of this polymer group. In this study, we describe the preparation of new copolymers based on hydrophilic Pluronic® F68 and PEI (F68PEI). F68PEI polyplexes obtained by doping with free F68 (1:2 and 1:5 w/w) allowed for fine-tuning of physicochemical properties and transfection activity, demonstrating improved in vitro transfection of the human bone osteosarcoma epithelial (U2OS) and oral squamous cell carcinoma (SCC-9) cells when compared to the parent formulation, F68PEI. Although all tested systems condensed pDNA at varying polymer/DNA charge ratios (N/P, 5/1–100/1), the addition of free F68 (1:5 w/w) resulted in the formation of smaller polyplexes (<200 nm). Analysis of polyplex properties by transmission electron microscopy and dynamic light scattering revealed varied polyplex morphology. Transfection potential was also found to be cell-dependent and significantly higher in SCC-9 cells compared to the control bPEI25k cells, as especially evident at higher N/P ratios (>25). The observed selectivity towards transfection of SSC-9 cells might represent a base for further optimization of a cell-specific transfection vehicle.
Penetration Routes of Oxygen and Moisture into the Insulation of FR-EPDM Cables for Nuclear Power Plants
Authors: Ohki Yoshimichi , Hirai Naoshi , Okada Sohei
Published: December 2022

The polymeric insulation used in nuclear power plants (NPPs) carries the risk of molecular breakage due to oxidation and hydrolysis in the event of an accident. With this in mind, tubular specimens of flame-retardant ethylene-propylene-diene rubber (FR-EPDM) insulation were obtained by taking conductors out of a cable harvested from an NPP. Similar tubular specimens were made from a newly manufactured cable and those aged artificially using a method called the “superposition of time-dependent data.” The inner and outer surfaces of each tubular specimen were subjected to various instrumental analyses to examine their oxidation, moisture uptake, and cross-linking. As a result, it has become clear that oxygen penetrates the cable through gaps between the twisted conductor strands. Meanwhile, water vapor diffuses more often through the sheath than through gaps between the conductor strands. Of the two methods used to simulate design-based accidents in NPPs, the one used to simulate the designed loss-of-coolant accident is more severe to FR-EPDM than the one used to simulate the designed severe accident. In addition, the validity of the method called the “superposition of time-dependent data,” which is used to give artificial aging treatments to cable samples, was confirmed. Measurements of spin-spin relaxation time and residual dipolar coupling using time-domain nuclear magnetic resonance were found suitable to use to obtain information on the cross-linking of FR-EPDM insulation.
Curing Kinetics of Bioderived Furan-Based Epoxy Resins: Study on the Effect of the Epoxy Monomer/Hardener Ratio
Authors: Marotta Angela , Faggio Noemi , Brondi Cosimo
Published: December 2022

The potential of furan-based epoxy thermosets as a greener alternative to diglycidyl ether of Bisphenol A (DGEBA)-based resins has been demonstrated in recent literature. Therefore, a deep investigation of the curing behaviour of these systems may allow their use for industrial applications. In this work, the curing mechanism of 2,5-bis[(oxiran-2-ylmethoxy)methyl]furan (BOMF) with methyl nadic anhydride (MNA) in the presence of 2-methylimidazole as a catalyst is analyzed. In particular, three systems characterized by different epoxy/anhydride molar ratios are investigated. The curing kinetics are studied through differential scanning calorimetry, both in isothermal and non-isothermal modes. The total heat of reaction of the epoxy resin as well as its activation energy are estimated by the non-isothermal measurements, while the fitting of isothermal data with Kamal’s autocatalytic model provides the kinetic parameters. The results are discussed as a function of the resin composition. The global activation energy for the curing process of BOMF/MNA resins is in the range 72–79 kJ/mol, depending on both the model used and the sample composition; higher values are experienced by the system with balanced stoichiometry. By the fitting of the isothermal analysis, it emerged that the order of reaction is not only dependent on the temperature, but also on the composition, even though the values range between 0.31 and 1.24.
A Computational Framework for Design and Optimization of Risk-Based Soil and Groundwater Remediation Strategies
Authors: Wang Xin , Li Rong , Tian Yong , Zhang Bowei , Zhao Ying , Zhang Tingting , Liu Chongxuan
Published: December 2022

Soil and groundwater systems have natural attenuation potential to degrade or detoxify contaminants due to biogeochemical processes. However, such potential is rarely incorporated into active remediation strategies, leading to over-remediation at many remediation sites. Here, we propose a framework for designing and searching optimal remediation strategies that fully consider the combined effects of active remediation strategies and natural attenuation potentials. The framework integrates machine-learning and process-based models for expediting the optimization process with its applicability demonstrated at a field site contaminated with arsenic (As). The process-based model was employed in the framework to simulate the evolution of As concentrations by integrating geochemical and biogeochemical processes in soil and groundwater systems under various scenarios of remedial activities. The simulation results of As concentration evolution, remedial activities, and associated remediation costs were used to train a machine learning model, random forest regression, with a goal to establish a relationship between the remediation inputs, outcomes, and associated cost. The relationship was then used to search for optimal (low cost) remedial strategies that meet remediation constraints. The strategy was successfully applied at the field site, and the framework provides an effective way to search for optimal remediation strategies at other remediation sites.
Low-Carbon and Low-Energy-Consumption Gear Processing Route Optimization Based on Gray Wolf Algorithm
Authors: Zhang Yani , Xu Haoshu , Huang Jun , Xiao Yongmao
Published: December 2022

The process of gear machining consumes a large amount of energy and causes serious pollution to the environment. Developing a proper process route of gear machining is the key to conserving energy and reducing emissions. Nowadays, the proper process route of gear machining is based on experience and is difficult to keep up with the development of modern times. In this article, a calculation model of low-carbon and low-energy consumption in gear machining processes was established based on an analysis of the machining process. With processing parameters as independent variables, the grey wolf algorithm was used to solve the problem. The effectiveness of the method was proven by an example of the machining process of an automobile transmission shaft.
Neural Network Model for Permeability Prediction from Reservoir Well Logs
Authors: Abdel Azim Reda , Aljehani Abdulrahman
Published: December 2022

The estimation of the formation permeability is considered a vital process in assessing reservoir deliverability. The prediction of such a rock property with the use of the minimum number of inputs is mandatory. In general, porosity and permeability are independent rock petrophysical properties. Despite these observations, theoretical relationships have been proposed, such as that by the Kozeny–Carmen theory. This theory, however, treats a highly complex porous medium in a very simple manner. Hence, this study proposes a comprehensive ANN model based on the back propagation learning algorithm using the FORTRAN language to predict the formation permeability from available well logs. The proposed ANN model uses a weight visualization curve technique to optimize the number of hidden neurons and layers. Approximately 500 core data points were collected to generate the model. These data, including gamma ray, sonic travel time, and bulk density, were collected from numerous wells drilled in the Western Desert and Gulf areas of Egypt. The results show that in order to predict the permeability accurately, the data set must be divided into 60% for training, 20% for testing, and 20% for validation with 25 neurons. The results yielded a correlation coefficient (R2) of 98% for the training and 96.5% for the testing, with an average absolute percent relative error (AAPRE) of 2.4%. To validate the ANN model, two published correlations (i.e., the dual water and Timur’s models) for calculating permeability were used to achieve the target. In addition, the results show that the ANN model had the lowest mean square error (MSE) of 0.035 and AAPRE of 0.024, while the dual water model yielded the highest MSE of 0.84 and APPRE of 0.645 compared to the core data. These results indicate that the proposed ANN model is robust and has strong capability of predicting the rock permeability using the minimum number of wireline log data.
Optimum Power Flow with Respect to the Capacitor Location and Size in Distribution Network
Authors: Maghami Mohammad Reza , Mutambara Arthur Guseni Oliver
Published: December 2022

In the past few decades, there has been increasing recognition of the importance of optimum power flow (OPF) studies in the context of economic analyses of power systems. There is a need for power system development to maximize efficiency by emphasizing cost and power losses for smart grids to operate effectively in the current situation. This study aims to develop an optimal capacitor bank allocation schedule that minimizes power losses in the distribution networks under equality constraints. This will be achieved by integrating the loss factor and voltage stability into a new approach to determine where the capacitor banks should be located. It aims to reduce the operating costs of power systems and maximize efficiency by applying an optimization model for economic dispatch, which considers distributed power generation and demand response. The NSGA-II optimization algorithm was used in this study to determine the optimal size and location of the capacitor bank. A NSGA-II solves this problem by minimizing cost and power losses while determining the best operating strategy. We used an IEEE 26-bus distribution system to test the proposed method with every possible generation change. Comparing the power flow analysis with/without capacitor optimization showed that the operation optimization model of OPF with NSGA-II can reduce operation costs and improve the power system.
Identification and Analysis of Factors Influencing Green Growth of Manufacturing Enterprises Based on DEMATEL Method—Wooden Flooring Manufacturing Companies as a Case
Authors: Li Wei , Wu Xia
Published: December 2022

It is significant to scientifically identify what factors influence the green growth of manufacturing enterprises and analyze the relationship among these factors, thus promoting green growth. Firstly, the corresponding conceptual model is designed; then, the DEMATEL method and steps used to identify the influencing factors are introduced; finally, the DEMATEL method is adopted to empirically analyze wooden flooring manufacturing companies so as to identify influencing factors of their green growth. According to the results, there are six reason factors, namely environmental standard constraints, green market demand, market competition, green technology advancement, upstream and downstream synergy of green industrial chain, and policy support, which provide the most important external support to enterprises’ green growth and main driving power to wooden flooring manufacturing ones.
From Synthetic Route of Silica Nanoparticles to Theranostic Applications
Authors: Pallavi Pragya , Harini Karthick , Alshehri Sultan , Ghoneim Mohammed M. , Alshlowi Areej , Gowtham Pemula , Girigoswami Koyeli , Shakeel Faiyaz , Girigoswami Agnishwar
Published: December 2022

The advancements in nanotechnology have quickly developed a new subject with vast applications of nanostructured materials in medicine and pharmaceuticals. The enormous surface-to-volume ratio, ease of surface modification, outstanding biocompatibility, and, in the case of mesoporous nanoparticles, the tunable pore size make the silica nanoparticles (SNPs) a promising candidate for nano-based medical applications. The preparation of SNPs and their contemporary usage as drug carriers, contrast agents for imaging, carrier of photosensitizers (PS) in photodynamic, as well as photothermal treatments are intensely discussed in this review. Furthermore, the potential harmful responses of silica nanoparticles are reviewed using data obtained from in vitro and in vivo experiments conducted by several studies. Moreover, we showcase the engineering of SNPs for the theranostic applications that can address several intrinsic limitations of conventional therapeutics and diagnostics. In the end, a personal perspective was outlined to state SNPs’ current status and future directions, focusing on SNPs’ significant potentiality and opportunities.
Finite Element and Neural Network Models to Forecast Gas Well Inflow Performance of Shale Reservoirs
Authors: Abdel Azim Reda , Aljehani Abdulrahman
Published: December 2022

Shale gas reservoirs are one of the most rapidly growing forms of natural gas worldwide. Gas production from such reservoirs is possible by using extensive and deep well fracturing to contact bulky fractions of the shale formation. In addition, the main mechanisms of the shale gas production process are the gas desorption that takes place by diffusion of gas in the shale matrix and by Darcy’s type through the fractures. This study presents a finite element model to simulate the gas flow including desorption and diffusion in shale gas reservoirs. A finite element model is used incorporated with a quadrilateral element mesh for gas pressure solution. In the presented model, the absorbed gas content is described by Langmuir’s isotherm equation. The non-linear iterative method is incorporated with the finite element technique to solve for gas property changes and pressure distribution. The model is verified against an analytical solution for methane depletion and the results show the robustness of the developed finite element model in this study. Further application of the model on the Barnett Shale field is performed. The results of this study show that the gas desorption in Barnett Shale field affects the gas flow close to the wellbore. In addition, an artificial neural network model is designed in this study based on the results of the validated finite element model and a back propagation learning algorithm to predict the well gas rates in shale reservoirs. The data created are divided into 70% for training and 30% for the testing process. The results show that the forecasting of gas rates can be achieved with an R2 of 0.98 and an MSE = 0.028 using gas density, matrix permeability, fracture length, porosity, PL (Langmuir’s pressure), VL (maximum amount of the adsorbed gas (Langmuir’s volume)) and reservoir pressure as inputs.
The Alleged Decline of Liberation Theology: Natural Death or Attempted Assassination?
Authors: Cousineau Madeleine
Published: December 2022

Is liberation theology dead or in decline? This article analyzes factors that have led to that perception and provides evidence to the contrary. It demonstrates that the theology has survived multiple attempts by certain sectors of both church and state to eliminate it, and that it remains very much alive in grassroots pastoral programs and social movements. Support for this last statement is provided by the author’s field research in Brazil. The article concludes with signs that liberation theology will endure as it continues to inspire spiritually motivated people who commit themselves to addressing human needs by promoting social justice.
Trauma, Despair and Faith: Generational Resonances in Exiled Tibetans
Authors: Vahali Honey Oberoi
Published: December 2022

Since the Holocaust much has been written about the violent horrors of the last and the present century. Suddenly recognized as the ‘hated and disowned other’ and driven away from their world of intimate connections, exiled people live with inexpressible angsts which are unconsciously passed on from parents to children, to their children and still further on. The shadow of the past is cast on refugees as unlike on any other diaspora. In spite of, or because of, the lived trauma, sometimes a creative symbolization of losses can take place as the collective makes space for emotional holding. This is indeed rare but not impossible. The present writing dwells on one such collective—the Tibetans housed in India with whom I have worked closely for long as a psychoanalytic researcher. The following account highlights certain ways in which the trauma of uprootedness offsets transgenerational crises and how an exodus acknowledges its past such that a simultaneous remembering and mourning of psychic pain and the carving out of hope is kept alive, especially for those who were exposed to the trials of violent displacement in childhood. Drawing from their inspiring movement that remains imbued by a Buddhist perspective, I also look forward to sharing a few thoughts on healing possibilities which hold restorative value for not only the Tibetans but humanity at large. In a fragmented world torn by the powerful aspiration of each country to become a mighty nation, the Buddhist stress on ‘non-self’ and universal responsibility offers a unique imagination of the ‘nation’ and important insights related to non-violence, forgiveness, compassion, selfhood, and a non-antagonistic relationship with the other—one’s perpetrator. It is of significance to note that such an ambiance is held in place by an attuned spiritual leader, the fourteenth Dalai Lama who mitigates the despair of generations by playing the role of a ‘transitional’ and ‘transformative object’. This writing also dwells on the role of a psychoanalytic researcher as an empathetic witness, a psychic container and a co-traveller.
On Pride, Flags and Flowers: Jerusalem’s Public Parades as a Mechanism for (de)Radicalisation
Authors: Solomon Sophia , Gal Kobi
Published: December 2022

The practice of public parades involving marches has been used historically by political and civic actors as a tool of helping to accomplish recognition of particular agendas or, at the very least, suggest a peaceful proclamation of justice within a democratic framework. Over the past two decades, The pride parade and The flag parade are drawing the attention of radical stakeholders in Israel whilst taking place in Jerusalem—a religiously divided space. Based on EU official reports and data from news reports and social media publications between 2002 and 2022, this paper examines religious extremists’ presence in the above parades, in parallel to the appearance of incitement, physical violence and vandalism. All as part of an ongoing Radicalisation process. In addition, it observes the establishment of The flower parade as a civic counter-response initiated by deradicalisation agents. The research reveals that under the values and rule of democracy, the mechanism of public parades can self-trigger a dynamic between participants and opposers, exploited by extreme collectives for violent purposes. It reflects upon a fundamental dispute between different interpretations of the connection between Judaism, nationality and family values in the light of the democratic framework. One is leading to religious-based exclusion agenda on the one hand, while the other is reacting with inclusion activities on the other.
Perception, Path Planning, and Flight Control for a Drone-Enabled Autonomous Pollination System
Authors: Rice Chapel Reid , McDonald Spencer Thomas , Shi Yang , Gan Hao , Lee Won Suk , Chen Yang , Wang Zhenbo
Published: December 2022

The decline of natural pollinators necessitates the development of novel pollination technologies. In this work, we propose a drone-enabled autonomous pollination system (APS) that consists of five primary modules: environment sensing, flower perception, path planning, flight control, and pollination mechanisms. These modules are highly dependent upon each other, with each module relying on inputs from the other modules. In this paper, we focus on approaches to the flower perception, path planning, and flight control modules. First, we briefly introduce a flower perception method from our previous work to create a map of flower locations. With a map of flowers, APS path planning is defined as a variant of the Travelling Salesman Problem (TSP). Two path planning approaches are compared based on mixed-integer programming (MIP) and genetic algorithms (GA), respectively. The GA approach is chosen as the superior approach due to the vast computational savings with negligible loss of optimality. To accurately follow the generated path for pollination, we develop a convex optimization approach to the quadrotor flight control problem (QFCP). This approach solves two convex problems. The first problem is a convexified three degree-of-freedom QFCP. The solution to this problem is used as an initial guess to the second convex problem, which is a linearized six degree-of-freedom QFCP. It is found that changing the objective of the second convex problem to minimize the deviation from the initial guess provides improved physical feasibility and solutions similar to a general-purpose optimizer. The path planning and flight control approaches are then tested within a model predictive control (MPC) framework where significant computational savings and embedded adjustments to uncertainty are observed. Coupling the two modules together provides a simple demonstration of how the entire APS will operate in practice.
ANN-Based Discernment of Septic and Inflammatory Synovial Fluid: A Novel Method Using Viscosity Data from a QCR Sensor
Authors: Miranda-Martínez Andrés , Sufrate-Vergara Berta , Fernández-Puntero Belén , Alcaide-Martin María José , Buño-Soto Antonio , Serrano-Olmedo José Javier
Published: December 2022

The synovial fluid (SF) analysis involves a series of chemical and physical studies that allow opportune diagnosing of septic, inflammatory, non-inflammatory, and other pathologies in joints. Among the variety of analyses to be performed on the synovial fluid, the study of viscosity can help distinguish between these conditions, since this property is affected in pathological cases. The problem with viscosity measurement is that it usually requires a large sample volume, or the necessary instrumentation is bulky and expensive. This study compares the viscosity of normal synovial fluid samples with samples with infectious and inflammatory pathologies and classifies them using an ANN (Artificial Neural Network). For this purpose, a low-cost, portable QCR-based sensor (10 MHz) was used to measure the viscous responses of the samples by obtaining three parameters: Δf, ΔΓ (parameters associated with the viscoelastic properties of the fluid), and viscosity calculation. These values were used to train the algorithm. Different versions of the ANN were compared, along with other models, such as SVM and random forest. Thirty-three samples of SF were analyzed. Our study suggests that the viscosity characterized by our sensor can help distinguish infectious synovial fluid, and that implementation of ANN improves the accuracy of synovial fluid classification.