bluuebunny/crossref_metadata_2025 huggingface dataset:
Co-Occurrence of Defoliating and Non-Defoliating Pathotypes of Verticillium Dahliae in Field-Grown Cotton Plants in New South Wales, Australia
Authors: Le Duy P. , Gregson Aphrika , Tran Thao T. , Jackson Rodney
Published: June 2020

Verticillium wilt (VW) is a major constraint to cotton production in Australia and worldwide. The disease is caused by a soilborne fungus, Verticillium dahliae, a highly virulent pathogen on cotton. Commonly, V. dahliae is designated into two pathotypes: defoliating (D) and non-defoliating (ND), based on induced symptoms. In the previous two survey seasons between 2017 and 2019, stems with suspected VW were sampled for the confirmation of presence and distribution of D and ND pathotypes across New South Wales (NSW), Australia. A total of 151 and 84 VW-suspected stems sampled from the 2017/18 and 2018/19 seasons, respectively, were subjected to pathogen isolation. Of these, 94 and 57 stems were positive for V. dahliae; and 18 and 20 stems sampled respectively from the two seasons yielded the D pathotype isolates. Two stems from the 2017/18 season and one stem from 2018/19 season yielded both D and ND pathotype isolates. We also successfully demonstrated the co-infection of both pathotypes in pot trials, which was driven predominantly by either of the pathotypes, and appeared independent on vegetative growth, fecundity and spore germination traits. Our study is the first report of the natural co-occurrence of both D and ND pathotypes in same field-grown cotton plants in NSW, to which a challenge to the disease management will be discussed.
Ethnobotany, Phytochemistry and Pharmacological Activity of Kigelia africana (Lam.) Benth. (Bignoniaceae)
Authors: Nabatanzi Alice , M. Nkadimeng Sanah , Lall Namrita , Kabasa John D. , J. McGaw Lyndy
Published: June 2020

Kigelia africana has been used in the management of human ailments since time immemorial. Ethnobotanists have documented the traditional uses of K. africana, which include treatment of skin disorders, cancer and gynecological complaints, among others. This has interested scientists, who have examined K. africana plant parts for their bioactivity. This review provides an insightful understanding on the ethnobotany, phytochemistry and pharmacology of K. africana. Web search engines Google and Google Scholar, as well as the databases of PubMed, Scopus, JSTOR, HINARI, SID, AJOL and Springer Link, were exhaustively searched using key words and phrases. Institutional reports and conference papers were also consulted. A total of 125 relevant international literature sources meeting the inclusion criteria were included. Kigelia africana has biologically active phytochemicals, many of which have been isolated. Whilst the fruits are most often cited in pharmacological studies, other plant parts are also used in herbal preparations. Commercially available products have been formulated from K. africana, though many have not been fully standardized. Despite many efforts by researchers to scientifically validate traditional uses of K. africana, many remain merely claims, thus the need to conduct more research, scientifically validate other traditional uses, isolate new bioactive phytochemicals and standardize K. africana products.
Ethylenediaminetetraacetic Acid (EDTA) Mitigates the Toxic Effect of Excessive Copper Concentrations on Growth, Gaseous Exchange and Chloroplast Ultrastructure of Corchorus capsularis L. and Improves Copper Accumulation Capabilities
Authors: Saleem Muhammad Hamzah , Ali Shafaqat , Kamran Muhammad , Iqbal Naeem , Azeem Muhammad , Tariq Javed Muhammad , Ali Qasim , Zulqurnain Haider Muhammad , Irshad Sana , Rizwan Muhammad , Alkahtani Saad , M. Abdel-Daim Mohamed
Published: June 2020

Copper (Cu) is an important micronutrient for a plant’s normal growth and development. However, excess amount of Cu in the soil causes many severe problems in plants—which ultimately affect crop productivity and yield. Moreover, excess of Cu contents causes oxidative damage in the plant tissues by generating excess of reactive oxygen species (ROS). The present experiment was designed to investigate the phytoextraction potential of Cu, morpho-physiological features and biochemical reaction of jute (Corchorus capsularis L.) seedlings using ethylenediaminetetraacetic acid (EDTA) of 3 mM under different Cu levels (0 (control), 50 and 100 μM) in a hydroponic nutrient solution (Hoagland). Our results showed that elevated Cu rates (50 and 100 μM) in the nutrient solution significantly reduced plant height, fresh and dry biomass, total chlorophyll content and gaseous exchange attributes in C. capsularis seedlings. As the concentration of Cu in the medium increased (50 and 100 μM), the level of malondialdehyde (MDA) and oxidative stress in C. capsularis seedlings also increased, which could have been controlled by antioxidant activity in particular plant cells. In addition, rising Cu concentration in the nutrient solution also increased Cu uptake and accumulation in roots and leaves as well as affected the ultrastructure of chloroplast of C. capsularis seedlings. The addition of EDTA to the nutrient solution significantly alleviated Cu toxicity in C. capsularis seedlings, showing a significantly increase in plant growth and biomass. MDA contents was not significantly increased in EDTA-induced plants, suggesting that this treatment was helpful in capturing ROS and thereby reducing ROS in in C. capsularis seedlings. EDTA modification with Cu, although the bioaccumulation factor in roots and leaves and translocation factor for the leaves of C. capsularis seedlings has significantly increased. These results indicate that C. capsularis has considerable potential to cope with Cu stress and is capable of removing a large quantity of Cu from the Cu-contaminated soil while using EDTA is a useful strategy to increase plant growth and biomass with Cu absorption capabilities.
Solid Polymer Electrolytes with Flexible Framework of SiO2 Nanofibers for Highly Safe Solid Lithium Batteries
Authors: Cui Jin , Zhou Zehao , Jia Mengyang , Chen Xin , Shi Chuan , Zhao Ning , Guo Xiangxin
Published: June 2020

Composite electrolytes consisting of polymers and three-dimensional (3D) fillers are considered to be promising electrolytes for solid lithium batteries owing to their virtues of continuous lithium-ion pathways and good mechanical properties. In the present study, an electrolyte with polyethylene oxide–lithium (bis trifluoromethyl) sulfate–succinonitrile (PLS) and frameworks of three-dimensional SiO2 nanofibers (3D SiO2 NFs) was prepared. Taking advantage of the highly conductive interfaces between 3D SiO2 NFs and PLS, the total conductivity of the electrolyte at 30 °C was approximately 9.32 × 10−5 S cm−1. With a thickness of 27 μm and a tensile strength of 7.4 MPa, the electrolyte achieved an area specific resistance of 29.0 Ω cm2. Moreover, such a 3D configuration could homogenize the electrical field, which was beneficial for suppressing dendrite growth. Consequently, Li/LiFePO4 cells assembled with PLS and 3D SiO2 NFs (PLS/3D SiO2 NFs), which delivered an original specific capacity of 167.9 mAh g−1, only suffered 3.28% capacity degradation after 100 cycles. In particular, these cells automatically shut down when PLS was decomposed above 400 °C, and the electrodes were separated by the solid framework of 3D SiO2 NFs. Therefore, the solid lithium batteries based on composite electrolytes reported here offer high safety at elevated temperatures.
Use of Multi-Hollow Polyester Particles as Opacifying Agent for Injection-Molded Polyethylene
Authors: F. A. Silva João , M. T. Carvalho Tânia , L. Almeida Margarida , Pereira Paula , Sousa Helena , Martins Jorge , Carvalho Luísa , D. Magalhães Fernão
Published: June 2020

Titanium dioxide is considered the most efficient white pigment for opacification of thermoplastics. However, its high cost, combined with strong price oscillations due to production bottlenecks, has been driving the industry towards alternatives that might allow reducing the titanium dioxide content, while maintaining the product’s opacity. A strategy commonly used in waterborne paints consists in adding hollow polymer particles to the formulation, therefore achieving opacification due to light refraction at the air/polymer interface. In the current work, we show preliminary results that indicate that a similar strategy can be followed for thermoplastics opacification, as long as thermoset particles are used, in order to ensure preservation of the hollow geometry during melt-processing. Multi-vesiculated crosslinked styrene–polyester particles, produced by a single-step double emulsion process, are used. Evidence of synergic interaction between the multi-hollow particles and titanium dioxide has been found.
Cutting Processes of Natural Fiber-Reinforced Polymer Composites
Authors: Masoud Fathi , Sapuan S.M. , Mohd Ariffin Mohd Khairol Anuar , Nukman Y. , Bayraktar Emin
Published: June 2020

Recently, natural fiber-reinforced polymers (NFRPs) have become important materials in many engineering applications; thus, to employ these materials some final industrial processes are needed, such as cutting, trimming, and drilling. Because of the heterogeneous nature of NFRPs, which differs from homogeneous materials such as metals and polymers, several defects have emerged when processing the NFRPs through traditional cutting methods such as high surface roughness and material damage at cutting zone. In order to overcome these challenges, unconventional cutting methods were considered. Unconventional cutting methods did not take into account the effects of cutting forces, which are the main cause of cutting defects in traditional cutting processes. The most prominent unconventional cutting processes are abrasive waterjet (AWJM) and laser beam (LBM) cutting technologies, which are actually applied for cutting various NFRPs. In this study, previously significant studies on cutting NFRPs by AWJM and LBM are discussed. The surface roughness, kerf taper, and heat-affected zone (HAZ) represent the target output parameters that are influenced and controlled by the input parameters of each process. However, this topic requires further studies on widening the range of material thickness and input parameter values.
Morphology and Mechanical Properties of 3D Printed Wood Fiber/Polylactic Acid Composite Parts Using Fused Deposition Modeling (FDM): The Effects of Printing Speed
Authors: Yang Teng-Chun , Yeh Chin-Hao
Published: June 2020

In this study, a wood fiber/polylactic acid composite (WPC) filament was used as feedstock to print the WPC part by means of fused deposition modeling (FDM). The morphology and mechanical properties of WPC parts printed at different speeds (30, 50, and 70 mm/s) were determined. The results show that the density of the printed WPC part increased as the printing speed decreased, while its surface color became darker than that of parts printed at a high speed. The printing time decreased with an increasing printing speed; however, there was a small difference in the time saving percentage without regard to the dimensions of the printed WPC part at a given printing speed. Additionally, the tensile and flexural properties of the printed WPC part were not significantly influenced by the printing speed, whereas the compressive strength and modulus of the FDM-printed part significantly decreased by 34.3% and 14.6%, respectively, when the printing speed was increased from 30 to 70 mm/s. Furthermore, scanning electronic microscopy (SEM) illustrated that the FDM process at a high printing speed produced an uneven surface of the part with a narrower width of printed layers, and pull-outs of wood fibers were more often observed on the fracture surface of the tensile sample. These results show that FDM manufacturing at different printing speeds has a substantial effect on the surface color, surface roughness, density, and compressive properties of the FDM-printed WPC part.
Defect Characteristics and Online Detection Techniques During Manufacturing of FRPs Using Automated Fiber Placement: A Review
Authors: Sun Shouzheng , Han Zhenyu , Fu Hongya , Jin Hongyu , Dhupia Jaspreet Singh , Wang Yang
Published: June 2020

Automated fiber placement (AFP) is an advanced manufacturing method for composites, which is especially suitable for large-scale composite components. However, some manufacturing defects inevitably appear in the AFP process, which can affect the mechanical properties of composites. This work aims to investigate the recent works on manufacturing defects and their online detection techniques during the AFP process. The main content focuses on the position defect in conventional and variable stiffness laminates, the relationship between the defects and the mechanical properties, defect control methods, the modeling method for a void defect, and online detection techniques. Following that, the contributions and limitations of the current studies are discussed. Finally, the prospects of future research concerning theoretical and practical engineering applications are pointed out.
Rheological, Mechanical and Morphological Characterization of Fillers in the Nautical Field: The Role of Dispersing Agents on Composite Materials
Authors: Vita Silvia , Ricotti Rico , Dodero Andrea , Vicini Silvia , Borchardt Per , Pinori Emiliano , Castellano Maila
Published: June 2020

Coatings have a fundamental role in covering the external surface of yachts by acting both as protective and aesthetic layers. In particular, fillers represent the essential layer from the point of view of mechanical properties and consist of a polymeric matrix, different extenders and additives, and dispersing agents, with the latter having the role to provide good extender-matrix compatibility. In the present work, the effects of dispersing agents with an ionic or steric action on the interactions between hollow glass microspheres and an epoxy-polyamide resin are evaluated. Un-crosslinked filler materials are studied via rheological tests, whereas the mechanical and morphological properties of the crosslinked samples are assessed. The results clearly indicate that steric dispersing agents provide a much greater compatibility effect compared to ionic ones, owing to their steric hindrance capability, thus leading to better-performing filler materials with a less-marked Payne effect, which is here proved to be an efficient tool to provide information concerning the extent of component interactions in nautical fillers. To the best of our knowledge, this work represents the first attempt to deeply understand the role of dispersing agents, which are until now empirically used in the preparation of fillers.
Synchrotron and Raman Study of the Rotator Phases and Polymorphism in Tricosane Paraffin
Authors: Blázquez-Blázquez Enrique , Barranco-García Rosa , Cerrada María L. , Martínez Juan C. , Pérez Ernesto
Published: June 2020

A detailed study of the phase behavior of n-paraffin C23H48 has been performed by means of real-time variable-temperature experiments with synchrotron radiation. Two detectors were employed for simultaneous analysis of the small-angle (SAXS) and wide-angle X-ray-scattering (WAXS) regions. This paraffin presents a very interesting phase behavior, involving two crystal polymorphs, three rotator phases and the liquid state. The Ostwald rule of stages is invoked to find similarities of the rotator phases with the eventual transient mesomorphic structure in the multistage model of polymer crystallization. That study is complemented by variable-temperature Raman experiments covering frequencies down to 150 cm−1. It was found that the low-frequency region is the most informative regarding the phase transitions, and specifically the intensity of the first overtone. From these analyses, several parameters are evaluated as function of temperature.
Dynamic Mechanical Damage and Non-Shock initiation of a New Polymer Bonded Explosive during Penetration
Authors: Li Xiao , Liu Yizhi , Sun Yi
Published: June 2020

Complexities of heating mechanisms make it difficult to investigate the safety of a polymer bonded explosive (PBX) charge of earth-penetrating-weapons (EPWs) during penetration. In this paper, the dynamic damage and non-shock initiation of PBX1314 (60 wt % hexahydro-1, 3, 5-trinitro-1, 3, 5-s-triazine (RDX), 16 wt % aluminum, 24 wt % hydroxy-terminated polybutadiene (HTPB)) during penetration is investigated through experiments and simulations. In the experiments, steel projectiles filled with PBX1314 are launched to penetrate concrete targets. In the results, non-shock initiations occur on the tail surface of PBX1314 along with mechanical damage of the tail and middle part of PBX1314. A dynamic damage and initiation model is proposed to characterize the effects of microcracks on the mechanical and thermal responses of PBX1314. Investigation based on the model suggests that microcrack interfacial friction plays significant roles in damage, heat generation and localization in PBX1314. A non-shock initiation criterion is developed based on macroscale variables in PBX1314. Numerical simulations of the penetration experiments are performed by using the proposed model and criterion. The mechanical damage and non-shock initiation of PBX1314 in the experiments are successfully predicted. The simulation results indicate that the tail of PBX1314 impacts the projectile repeatedly during penetration. Finally, the initiation criterion is satisfied because of frictional heat localization near microcrack surfaces and initiation is activated in the tail of PBX1314.
Assessment of Supercritical CO2 Extraction as a Method for Plastic Waste Decontamination
Authors: Alassali Ayah , Aboud Noor , Kuchta Kerstin , Jaeger Philip , Zeinolebadi Ahmad
Published: June 2020

Due to the lack of advanced methods to clean plastic waste from organic contaminants, this study aimed at evaluating supercritical extraction as a decontamination method. Oil-adhesive high-density polyethylene (HD-PE) oil containers were subjected to supercritical extraction using supercritical carbon dioxide. The extraction was conducted at 300 bar, applying various temperatures (i.e., 70, 80 and 90 °C). The study assessed the impact of temperature on the decontamination efficiency. The variation in the samples’ quality was first analyzed using near infrared (NIR) spectroscopy. An analysis of the content of polycyclic aromatic hydrocarbons (PAHs) was followed. Samples treated at 70 and 80 °C showed higher extraction efficiencies, in spite of the lower extraction temperatures. The NIR analysis showed that the plastic specimens did not experience degradation by the supercritical decontamination method. Moreover, the NIR spectra of the extracted oil showed the presence of a wide range of compounds, some of which are hazardous. This has been confirmed by a GC-MS analysis of the extracted oil. Based on the provided assessment, the quality of the decontaminated HD-PE plastic samples—from a contamination point of view—is enhanced in comparison to untreated samples. The level of PAHs contamination decreased to be within the allowed limits defined by the REACH regulation, and also met the specifications of the German Product Safety Committee. This study proved the effectiveness of the supercritical extraction using CO2 in extracting organic contaminants from plastics, while maintaining their quality.
Crosslinked Sulfonated Polyphenylsulfone-Vinylon (CSPPSU-vinylon) Membranes for PEM Fuel Cells from SPPSU and Polyvinyl Alcohol (PVA)
Authors: Kim Je-Deok , Matsushita Satoshi , Tamura Kenji
Published: June 2020

A crosslinked sulfonated polyphenylsulfone (CSPPSU) polymer and polyvinyl alcohol (PVA) were thermally crosslinked; then, a CSPPSU-vinylon membrane was synthesized using a formalization reaction. Its use as an electrolyte membrane for fuel cells was investigated. PVA was synthesized from polyvinyl acetate (PVAc), using a saponification reaction. The CSPPSU-vinylon membrane was synthesized by the addition of PVA (5 wt%, 10 wt%, 20 wt%), and its chemical, mechanical, conductivity, and fuel cell properties were studied. The conductivity of the CSPPSU-10vinylon membrane is higher than that of the CSPPSU membrane, and a conductivity of 66 mS/cm was obtained at 120 °C and 90% RH (relative humidity). From a fuel cell evaluation at 80 °C, the CSPPSU-10vinylon membrane has a higher current density than CSPPSU and Nafion212 membranes, in both high (100% RH) and low humidification (60% RH). By using a CSPPSU-vinylon membrane instead of a CSPPSU membrane, the conductivity and fuel cell performance improved.
Broadband Dielectric Spectroscopy Study of Biobased Poly(alkylene 2,5-furanoate)s’ Molecular Dynamics
Authors: Soccio Michelina , Martínez-Tong Daniel E. , Guidotti Giulia , Robles-Hernández Beatriz , Munari Andrea , Lotti Nadia , Alegria Angel
Published: June 2020

Poly(2,5-alkylene furanoate)s are bio-based, smart, and innovative polymers that are considered the most promising materials to replace oil-based plastics. These polymers can be synthesized using ecofriendly approaches, starting from renewable sources, and result into final products with properties comparable and even better than those presented by their terephthalic counterparts. In this work, we present the molecular dynamics of four 100% bio-based poly(alkylene 2,5-furanoate)s, using broadband dielectric spectroscopy measurements that covered a wide temperature and frequency range. We unveiled complex local relaxations, characterized by the simultaneous presence of two components, which were dependent on thermal treatment. The segmental relaxation showed relaxation times and strengths depending on the glycolic subunit length, which were furthermore confirmed by high-frequency experiments in the molten region of the polymers. Our results allowed determining structure–property relations that are able to provide further understanding about the excellent barrier properties of poly(alkylene 2,5-furanoate)s. In addition, we provide results of high industrial interest during polymer processing for possible industrial applications of poly(alkylene furanoate)s.
A Fractal-Based Correlation for Time-Dependent Surface Diffusivity in Porous Adsorbents
Authors: Inglezakis Vassilis J. , Balsamo Marco , Montagnaro Fabio
Published: June 2020

Fluid–solid adsorption processes are mostly governed by the adsorbate transport in the solid phase and surface diffusion is often the limiting step of the overall process in microporous materials such as zeolites. This work starts from a concise review of concepts and models for surface transport and variable surface diffusivity. It emerges that the phenomenon of hindered surface diffusion for monolayer adsorption, which is common in zeolites, and models able to fit a non-monotonic trend of surface diffusivity against adsorbate solid phase concentration, have received limited attention. This work contributes to the literature of hindered diffusion by formulating a time-dependent equation for surface diffusivity based on fractal dynamics concepts. The proposed equation takes into account the contributions of both fractal-like diffusion (a time-decreasing term) and hopping diffusion (a time-increasing term). The equation is discussed and numerically analyzed to testify its ability to reproduce the possible different patterns of surface diffusivity vs. time.
Covalently Cross-Linked Nanoparticles Based on Ferulated Arabinoxylans Recovered from a Distiller’s Dried Grains Byproduct
Authors: De Anda-Flores Yubia , Carvajal-Millan Elizabeth , Lizardi-Mendoza Jaime , Rascon-Chu Agustin , Martínez-López Ana Luisa , Marquez-Escalante Jorge , Brown-Bojorquez Francisco , Tanori-Cordova Judith
Published: June 2020

The purpose of this investigation was to extract ferulated arabinoxylans (AX) from dried distillers’ grains with solubles (DDGS) plus to investigate their capability to form covalently cross-linked nanoparticles. AX registered 7.3 µg of ferulic acid/mg polysaccharide and molecular weight and intrinsic viscosity of 661 kDa and 149 mL/g, correspondingly. Fourier transform infrared spectroscopy (FTIR) was used to confirm the identity of this polysaccharide. AX formed laccase induced covalent gels at 1% (w/v), which registered an elastic modulus of 224 Pa and a content of FA dimers of 1.5 µg/mg polysaccharide. Scanning electron microscopy pictures of AX gels exhibited a microstructure resembling a rough honeycomb. AX formed covalently cross-linked nanoparticles (NAX) by coaxial electrospray. The average hydrodynamic diameter of NAX determined by dynamic light scattering was 328 nm. NAX presented a spherical and regular shape by transmission electron microscopy analysis. NAX may be an attractive material for pharmaceutical and biomedical applications and an option in sustainable DDGS use.
Performance Assessment of SWRO Spiral-Wound Membrane Modules with Different Feed Spacer Dimensions
Authors: Ruiz-García A. , Nuez I.
Published: June 2020

Reverse osmosis is the leading process in seawater desalination. However, it is still an energy intensive technology. Feed spacer geometry design is a key factor in reverse osmosis spiral wound membrane module performance. Correlations obtained from experimental work and computational fluid dynamics modeling were used in a computational tool to simulate the impact of different feed spacer geometries in seawater reverse osmosis spiral wound membrane modules with different permeability coefficients in pressure vessels with 6, 7 and 8 elements. The aim of this work was to carry out a comparative analysis of the effect of different feed spacer geometries in combination with the water and solute permeability coefficients on seawater reverse osmosis spiral wound membrane modules performance. The results showed a higher impact of feed spacer geometries in the membrane with the highest production (highest water permeability coefficient). It was also found that the impact of feed spacer geometry increased with the number of spiral wound membrane modules in series in the pressure vessel. Installation of different feed spacer geometries in reverse osmosis membranes depending on the operating conditions could improve the performance of seawater reverse osmosis systems in terms of energy consumption and permeate quality.
An Artificial Intelligence Approach to Predict the Thermophysical Properties of MWCNT Nanofluids
Authors: Bakthavatchalam Balaji , Shaik Nagoor Basha , Hussain Patthi Bin
Published: June 2020

Experimental data of thermal conductivity, thermal stability, specific heat capacity, viscosity, UV–vis (light transmittance) and FTIR (light absorption) of Multiwalled Carbon Nanotubes (MWCNTs) dispersed in glycols, alcohols and water with the addition of sodium dodecylbenzene sulfonate (SDBS) surfactant for 0.5 wt % concentration along a temperature range of 25 °C to 200 °C were verified using Artificial Neural Networks (ANNs). In this research, an ANN approach was proposed using experimental datasets to predict the relative thermophysical properties of the tested nanofluids in the available literature. Throughout the designed network, 65% and 25% of data points were comprehended in the training and testing set while the other 10% was utilized as a validation set. The parameters such as temperature, concentration, size and time were considered as inputs while the thermophysical properties were considered as outputs to develop ANN models of further predictions with unseen datasets. The results found to be satisfactory as the (coefficient of determination) R2 values are close to 1.0. The predicted results of the nanofluids’ thermophysical properties were then validated with experimental dataset values. The validation plots of all individual samples for all properties were graphically generated. A comparison study was conducted for the robustness of the proposed approach. This work may help to reduce the experimental time and cost in the future.
Kaempferol Rhamnosides from Geranium sibiricum as Aldose Reductase Inhibitors and Their Content by HPLC Analysis
Authors: Quilantang Norman , Choi Kyung , Lee Bog-Hieu , Lee Sanghyun
Published: June 2020

The study aimed to assess the aldose reductase (AR) inhibition of selected Geranium species and determine the bioactive flavonoid constituents. Flavonoids are known to be good AR inhibitors. Among the species examined, G. sibiricum exhibited potent inhibition of AR (IC50 value, 2.4 µg/mL). Further examination of G. sibiricum, after solvent extraction and fractionation, revealed that the ethyl acetate fraction (IC50 value, 0.41 µg/mL) had a potent AR inhibitory effect. Kaempferol rhamnosides were the active compounds from this fraction. Moreover, G. sibiricum showed the highest content of kaempferol-7-O-rhamnoside and kaempferol-3,7-O-dirhamnoside among the samples examined with a concentration in the extracts of 28.1 and 2.2 mg/g, respectively. This study shows that G. sibiricum exhibits promising AR inhibitory activity, which can be explored further as a natural therapy for treating and managing complications associated with diabetes.
A Nodes-Based Non-Structural Model Considering a Series Structure for Heat Exchanger Network Synthesis
Authors: Xu Yue , Kayange Heri Ambonisye , Cui Guomin
Published: June 2020

The aim of heat exchanger network synthesis is to design a cost-effective network configuration with the maximum energy recovery. Therefore, a nodes-based non-structural model considering a series structure (NNM) is proposed. The proposed model utilizes a simple principle based on setting the nodes on streams such that to achieve optimization of a heat exchanger network synthesis (HENS) problem. The proposed model uses several nodes to quantify the possible positions of heat exchangers so that the matching between hot and cold streams is random and free. Besides the stream splits, heat exchangers with series structures are introduced in the proposed model. The heuristic algorithm used to solve NNM model is a random walk algorithm with compulsive evolution. The proposed model is used to solve four scale cases of a HENS problem, the results show that the costs obtained by NNM model can be respectively lower 3226 $/a(Case 1), 11,056 $/a(Case 2), 2463 $/a(Case 3), 527 $/a(Case 4) than the best costs listed in literature.
Unconfined Dense Plunging Jets Used for Brine Disposal from Desalination Plants
Authors: Chow Aaron C. , Shrivastava Ishita , Adams E. Eric , Al-Rabaie Fahed , Al-Anzi Bader
Published: June 2020

Laboratory experiments were conducted to measure entrained air bubble penetration depth and dilution of a dense vertical unconfined plunging jet to evaluate its performance as an outfall to dilute brine from desalination plants as well as a means to aerate water column. Experiments involved neutrally buoyant or dense plunging jets discharging in quiescent receiving water. The density difference between effluent and receiving water, the plunging jet length (height above water surface), and the receiving water salinity were varied in the experiments. Observed penetration depth for neutrally buoyant jets was somewhat greater than previously reported, and increased modestly with jet density. Increasing density also resulted in an increasing number of fine bubbles descending together with the dense plume. These observations can help guide the design of plunging jets to mitigate anoxic conditions in the water column when brine is introduced to a receiving water body, as with seawater desalination.
Physico-Chemical Changes, Microbiological Properties, and Storage Shelf Life of Cow and Goat Milk from Industrial High-Pressure Processing
Authors: Tan Sok Fern , Chin Nyuk Ling , Tee Tuan Poy , Chooi Sook Kuan
Published: June 2020

Industrial high-pressure processing (HPP) was conducted on cow and goat milk in comparison to conventional heat pasteurization. No significant changes were found in the physico-chemical properties of the treated milk except for pH, where pasteurized cow milk experienced a decrease while goat milk’s pH increased for both pasteurized and HPP treated. HPP-treated cow and goat milk both achieved microbial shelf life of 22 days at 8 °C storage with no increase in Bacillus cereus, mesophilic aerobic spores, coliform, yeast and mold but slight increase in psychrotrophic bacteria and total plate count. Pasteurized goat milk was spoilt at the end of storage with exceeding count of psychrotrophic bacteria (9.0 × 108 CFU/mL) and total plate count (3.5 × 108 CFU/mL). HPP-treated cow milk exhibited higher physico-chemical stability than goat milk as evidenced by non-significant change of titratable acidity but goat milk experienced an increase of 0.04% averagely.
Effect of Purification Methods on Commercially Available Cellulose Nanocrystal Properties and TEMPO Oxidation
Authors: Banerjee Manali , Saraswatula Sisira , Williams Anna , Brettmann Blair
Published: June 2020

Cellulose nanocrystals (CNCs) are attractive for use in polymer composites, biomedical applications, and barrier packaging. In all of these applications they are mixed with other components and compatibility is a major design consideration, as CNCs naturally have a high density of surface hydroxyl groups and primarily disperse well in polar media. Numerous surface modification approaches have been used to address these issues, but challenges remain due to the variability in the commercially available CNC materials. CNCs can be produced from biomass using several extraction methods, most notably acid hydrolysis and biomass extraction, also known as the American Value Added Pulping process. The production method of the CNC material has an impact on both physical and surface properties of CNCs, including size, shape, crystal structure, and zeta potential. In addition, post-treatments can be used to purify the CNC material and further alter these properties. This work studies the properties of CNCs from three different commercial suppliers and after conducting three different post-treatments: dialysis, Soxhlet extraction, and acetone washing to understand the effect of the commercial source and purification on CNC surface properties and modification via 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) mediated oxidation. We show that there is significant variation in CNC physical and surface properties between different commercial suppliers before and after purification. Importantly, we show that for CNCs produced through acid hydrolysis, acetone washing or Soxhlet extraction in ethanol decreases the achievable degree of TEMPO modification, but makes it more consistent between the different commercial suppliers. This has important implications for improving reproducibility in CNC research as well as aiding the expanding fields of applications.
Classification and Comparison of Dividing Walls for Distillation Columns
Authors: Chen Zewei , Agrawal Rakesh
Published: June 2020

A classification method is proposed to classify dividing walls into 5 types. Each type of dividing wall has its unique structural characteristics which impact its total vapor duty, construction complexity and controllability. Based on this classification, a comprehensive guideline to draw optimal dividing wall columns for any n-component distillation is provided.
Investigation of C-Band SAR Polarimetry for Mapping a High-Tidal Coastal Environment in Northern Canada
Authors: Omari Khalid , Chenier René , Touzi Ridha , Sagram Mesha
Published: June 2020

Synthetic Aperture Radar (SAR) has been used in characterizing intertidal zones along northern Canadian coastlines. RADARSAT-2, with its full polarimetric information, has been considered for monitoring these vulnerable ecosystems and helping enhance the navigational safety of these waters. The RADARSAT Constellation Mission (RCM) will ensure data continuity with three identical SAR satellites orbiting together, providing superior revisit capabilities. The three satellites are equipped with multiple configurations, including single-polarization (HH, HV, VV), conventional (HH-HV, VV-VH, and HH-VV), hybrid (i.e., compact) dual polarization, and fully polarimetric (FP) modes. This study investigates the potential of the compact polarimetric (CP) mode for mapping an intertidal zone located at Tasiujaq village on the southwest shore of Ungava Bay, Quebec. Simulated RCM data were generated using FP RADARSAT-2 images collected over the study site in 2016. Commonly used tools for CP analysis include Raney m-delta classification and the hybrid dual polarizations RH-RV (where the transmitter is right-circular and the receivers are horizontal and vertical linear polarizations) and RR-RL (where the transmitter is right circular and the receivers are right-circular and left-circular polarizations). The potential of CP is compared with single, conventional dual-pol, and FP. The Freeman–Durden and Touzi discriminators are used for FP analysis. The random forest classifier is used as a classification approach due to its well-documented performance compared to other classifiers. The results suggest that the hybrid compact (RR-RL and RH-RV) dual polarizations provide encouraging separability capacities with overall accuracies of 61% and 60.7%, respectively, although they do not perform as well as conventional dual-pol HH-HV (64.4%). On the other hand, the CP polarimetric m-delta decomposition generated slightly less accurate classification results with an overall accuracy of approximately 62% compared to the FP Freeman–Durden (67.08%) and Touzi discriminators (71.1%).
Spatiotemporal Derivation of Intermittent Ponding in a Maize–Soybean Landscape from Planet Labs CubeSat Images
Authors: Paul Robert F. , Cai Yaping , Peng Bin , Yang Wendy H. , Guan Kaiyu , DeLucia Evan H.
Published: June 2020

Climate change is increasing the frequency and intensity of heavy precipitation in the US Midwest, overwhelming existing tile drainage, and resulting in temporary soil ponding across the landscape. However, lack of direct observations of the dynamics of temporal soil ponding limits our understanding of its impacts on crop growth and biogeochemical cycling. Satellite remote sensing offers a unique opportunity to observe and analyze this dynamic phenomenon at the landscape scale. Here we analyzed a series of red–green–blue (RGB) and near infrared (NIR) remote sensing images from the Planet Labs CubeSat constellation following a period of heavy precipitation in May 2017 to determine the spatiotemporal characteristics of ponding events in the maize–soybean cropland of Champaign County, Illinois USA. We trained Random Forest algorithms for near-daily images to create binary classifications of surface water versus none, which achieved kappa values around 0.9. We then analyzed the morphology of classification results for connected pixels across space and time and found that 2.5% (5180 ha) of this cropland was classified as water surface at some point during this period. The frequency distribution of areal ponding extent exhibited a log–log relationship; the mean and median areas of ponds were 1231 m2 and 126 m2, respectively, with 26.1% of identified ponds being at the minimum threshold area of 45 m2, and 2.5% of the ponds having an area greater than 104 m2 (1 ha). Ponds lasted for a mean duration of 2.4 ± 1.7 days, and 2.3% of ponds lasted for more than a week. Our results suggest that transient ponding may be significant at the landscape scale and ought to be considered in assessments of crop risk, soil and water conservation, biogeochemistry, and sustainability.
Angular Light, Polarization and Stokes Parameters Information in a Hybrid Image Sensor with Division of Focal Plane
Authors: Freitas Carvalho Francelino , Augusto de Moraes Cruz Carlos , Costa Marques Greicy , Martins Cruz Damasceno Kayque
Published: June 2020

Targeting 3D image reconstruction and depth sensing, a desirable feature for complementary metal oxide semiconductor (CMOS) image sensors is the ability to detect local light incident angle and the light polarization. In the last years, advances in the CMOS technologies have enabled dedicated circuits to determine these parameters in an image sensor. However, due to the great number of pixels required in a cluster to enable such functionality, implementing such features in regular CMOS imagers is still not viable. The current state-of-the-art solutions require eight pixels in a cluster to detect local light intensity, incident angle and polarization. The technique to detect local incident angle is widely exploited in the literature, and the authors have shown in previous works that it is possible to perform the job with a cluster of only four pixels. In this work, the authors explore three novelties: a mean to determine three of four Stokes parameters, the new paradigm in polarization cluster-pixel design, and the extended ability to detect both the local light angle and intensity. The features of the proposed pixel cluster are demonstrated through simulation program with integrated circuit emphasis (SPICE) of the regular Quadrature Pixel Cluster and Polarization Pixel Cluster models, the results of which are compliant with experimental results presented in the literature.
Development of Thermal Principles for the Automation of the Thermographic Monitoring of Cultural Heritage
Authors: Garrido Iván , Lagüela Susana , Sfarra Stefano , Arias Pedro
Published: June 2020

The continuous deterioration of elements, with high patrimonial value over time, can only be mitigated or annulled through the application of techniques that facilitate the preventative detection of the possible agents of deterioration. InfraRed Thermography (IRT) is one of the most used techniques for this task. However, there are few IRT methodologies, which can automatically monitor the cultural heritage field, and are vitally important in eliminating the subjectivity in interpreting and accelerating the analysis process. In this work, a study is performed on a tessellatum layer of a mosaic to automatically: (i) Detect the first appearance of the thermal footprint of internal water, (ii) delimit the contours of the thermal footprint of internal water from its first appearance, and (iii) classify between harmful and non-harmful internal water. The study is based on the analysis of the temperature distribution of each thermal image. Five thermal images sequences are acquired during the simulation of different real situations, obtaining a set of promising results for the optimization of the thermographic inspection process, while discussing the following recommended steps to be taken in the study for future researches.
Design and Development of a Fully Printed Accelerometer with a Carbon Paste-Based Strain Gauge
Authors: Liu Mingjie , Zhang Qi , Zhao Yulong , Shao Yiwei , Zhang Dongliang
Published: June 2020

In this paper, we present a fully printed accelerometer with a piezoresistive carbon paste-based strain gauge printed on its surface, which can be manufactured at low cost and with high efficiency. This accelerometer is composed of two parts: a sensor substrate made from high-temperature resin, which is printed by a 3D printer based on stereolithography apparatus (SLA), and a carbon paste-based strain gauge fabricated by screen-printing technology and by direct ink writing (DIW) technology for the purposes of comparison and optimization. First, the structural design, theoretical analysis, simulation analysis of the accelerometer, and analyses of the conductive mechanism and the piezoresistive mechanism of the carbon paste-based strain gauge were carried out. Then the proposed accelerometer was fabricated by a combination of different printing technologies and the curing conditions of the carbon paste were investigated. After that, the accelerometers with the screen-printed strain gauge and DIW strain gauge were characterized. The results show that the printing precision of the screen-printing process on the sensor substrate is higher than the DIW process, and both accelerometers can perform acceleration measurement. Also, this kind of accelerometer can be used in the field of measuring body motion. All these findings prove that 3D printing technology is a significant method for sensor fabrication and verification.
Special Issue “Fiber Optic Sensors and Applications”: An Overview
Authors: Wei Lei , Tjin Swee Chuan
Published: June 2020

We present here the recent advance in exploring new detection mechanisms, materials, processes, and applications of fiber optic sensors.
Volumetric Change Detection in Bedrock Coastal Cliffs Using Terrestrial Laser Scanning and UAS-Based SfM
Authors: Hayakawa Yuichi S. , Obanawa Hiroyuki
Published: June 2020

Three-dimensional (3D) morphological changes in rocky coasts need to be precisely measured for protecting coastal areas and evaluating the associated sediment dynamics, although volumetric measurements of bedrock erosion in rocky coasts have been limited due to the lack of appropriate measurement methods. Here we carried out repeat surveys of the 3D measurements of a small coastal island using terrestrial laser scanning (TLS) and structure-from-motion (SfM) photogrammetry with an unmanned aerial system (UAS) for 5 years. The UAS-SfM approach measures the entire shape of the island, whereas the TLS measurement enables to obtain more accurate morphological data at a scale of centimeters on the land side. The multitemporal TLS-derived data were first aligned in timeline by the iterative closest point (ICP) method and they were used as positionally correct references. The UAS-SfM data were then aligned to each of the TLS-derived data by ICP to improve its positional accuracy. The changed areas for each period was then extracted from the aligned UAS-derived point clouds and were converted to 3D mesh polygons, enabling a differential volume estimate (DVE). The DVE for each period was revealed to be from 3.1 to 77.2 m3/month. These changes are rapid enough to force the coastal bedrock island to disappear in 30 years. The temporal variations in the DVE is roughly associated with those in the frequency of high tidal waves.
Realtime Localization and Estimation of Loads on Aircraft Wings from Depth Images
Authors: Bilal Diyar Khalis , Unel Mustafa , Yildiz Mehmet , Koc Bahattin
Published: June 2020

This paper deals with the development of a realtime structural health monitoring system for airframe structures to localize and estimate the magnitude of the loads causing deflections to the critical components, such as wings. To this end, a framework that is based on artificial neural networks is developed where features that are extracted from a depth camera are utilized. The localization of the load is treated as a multinomial logistic classification problem and the load magnitude estimation as a logistic regression problem. The neural networks trained for classification and regression are preceded with an autoencoder, through which maximum informative data at a much smaller scale are extracted from the depth features. The effectiveness of the proposed method is validated by an experimental study performed on a composite unmanned aerial vehicle (UAV) wing subject to concentrated and distributed loads, and the results obtained by the proposed method are superior when compared with a method based on Castigliano’s theorem.
A Hough-Space-Based Automatic Online Calibration Method for a Side-Rear-View Monitoring System
Authors: Lee Jung Hyun , Lee Dong-Wook
Published: June 2020

We propose an automatic camera calibration method for a side-rear-view monitoring system in natural driving environments. The proposed method assumes that the camera is always located near the surface of the vehicle so that it always shoots a part of the vehicle. This method utilizes photographed vehicle information because the captured vehicle always appears stationary in the image, regardless of the surrounding environment. The proposed algorithm detects the vehicle from the image and computes the similarity score between the detected vehicle and the previously stored vehicle model. Conventional online calibration methods use additional equipment or operate only in specific driving environments. On the contrary, the proposed method is advantageous because it can automatically calibrate camera-based monitoring systems in any driving environment without using additional equipment. The calibration range of the automatic calibration method was verified through simulations and evaluated both quantitatively and qualitatively through actual driving experiments.