bluuebunny/crossref_metadata_2025 huggingface dataset:
Diversity of the caddisflies (Trichoptera) of Bulgaria
Authors: Evtimova Vesela
Published: September 2019

Conservation of freshwater environments and assessment of their ecosystem services as a function of biodiversity are key research objectives with global importance. Additionally, the taxonomic composition of aquatic communities, including benthic macroinvertebrates, is crucial for the evaluation of the ecological status of the water bodies they inhabit. Numerous biotic indices and metrics have been developed based on freshwater benthic invertebrates. This contribution focuses on the order Trichoptera, as it includes diverse sensitive taxa with specific requirements to their environment. The aim was to summarise the current knowledge on morpho-taxonomy of adult and larval stages of Bulgarian caddisflies based on published and original data. The only checklist of Bulgarian caddisflies was published in the 1980s by Kumanski 1981 and included 218 species from 76 genera. This checklist was mostly based on adult Trichoptera. It was followed by two monographs (Kumanski 1985, Kumanski 1988) and numerous scientific papers (mostly by the same author, e.g. Kumanski 1993, Kumanski 2007) that by 2007 increased the number of known caddisflies from Bulgaria to 258 species. Based on the literature and on original data, the number of valid species of Trichoptera in Bulgaria is estimated to 255. They are from 78 genera, belonging to 20 families. Worldwide, adult forms are better studied, while not all of the larval stages of caddisflies are currently known or described. More than 100 of the Bulgarian caddisflies (almost 40%) lack larval description. This is likely owing to their limited geographical distribution and insufficient studies on the aquatic stages of Bulgarian Trichoptera over the last decades. Additionally, some of the representatives of the order are endemic for the Balkan Peninsula or Bulgaria.
Nematode diversity in four crop types (pea, apple, lavender and rose) in southern Bulgaria
Authors: Lazarova Stela , Mladenov Aleksandar , Lozanova Lyudmila , Peneva Vlada
Published: September 2019

Nematodes represent one of the largest phyla in the animal kingdom and are a key component of the soil microfauna (organisms with body width <0.2 mm). Being a widespread and diverse group, they display a wide range of adaptations and lifestyle traits. Their functional role in soil food-webs is mostly related to their feeding type. The majority of terrestrial nematodes feed on plant roots, bacteria and fungi, while a small group of plant associated species spend part or their whole life cycle in roots. Some plant-feeding species are known as important pests that can parasitize various crops causing adverse effects on yield and production quality. Their effective management requires accurate detection and identification. In the frame of the National Research Program "Healthy Foods for a Strong Bio-Economy and Quality of Life", selected groups of soil nematodes are used as bioindicators for assessing soil and plant health, and ecosystem services in several agricultural ecosystems. Nematode communities from four crop types (pea, apple, lavender and rose) in southern Bulgaria managed by conventional and organic farming were sampled and investigated. Here we present some preliminary results on pea, lavender and rose associated nematode diversity. Multiple core samples from 18 sampling plots were collected in June 2019. Nematodes were isolated from 200 g of soil by decanting and sieving method, fixed, dehydrated and mounted on permanent slides. Overall, over 60 genera belonging to five trophic groups were identified. Approximately half of the nematode genera found are obligatory plant- and plant/fungus feeders. Parasitic nematodes were represented by 12 genera, some of which include important pests known to cause severe damages on crops e.g. Meloidogyne Goeldi, 1889, Pratylenchus Filipjev, 1934, Pratylenchoides Winslow, 1958 and Tylenchorhynchus Cobb, 1913.
Investigation of Thermoelectric Performance of MoS2-Templated Polyaniline Nanocomposites
Authors: Ali Mariam K. , Moneim A.A.
Published: September 2019

Polyaniline has attracted a lot of attention for thermoelectric (T.E) applications, however their drawback materials is that they possess low power factors than the state-of-the-art materials such as BiTe-based, BiSb-based, PbTe-based, etc. [1-4]. Currently, in order to enhance the T.E properties, hybrids between the polymer and other components such as carbon materials, other polymers, and even inorganic materials are being investigated. In this work, the effect of MoS2 addition on the T.E properties of polyaniline was investigated. The MoS2 nanoflowers were first synthesized via hydrothermal process at 200 °C for 24 hrs after which they were used for templated in situ polymerization of polyaniline. The scanning electron microscope (SEM) image showed that the MoS2 nanoflowers were covered with the polyaniline during the polymerization process and this was confirmed from the X-ray diffraction (XRD) analysis which showed existence of both the polyaniline and MoS2 in the synthesized material. The electrical conductivity of polyaniline was reported to be 10-3 S cm-1 and it was noticed that addition of minute amounts of MoS2 into polyaniline resulted in an enhancement of the electrical conductivities of up to two orders of magnitude. Nanocomposite with 5 % MoS2 (PMX-5) showed optimized power factor values ranging from 6.30 x 10-2 - 1.12 x 10-3 μW m-1 K-2 for the temperature range studied. This study therefore provides a facile approach for synthesis of polyaniline-molybdenum disulphide nanocomposites and the results obtained confirm that transition metal dichalcogenides (TMDs) have a potential for the enhancement of T.E properties of polyaniline.
Fracture Toughness of CF-Plug Joints of Ti and Epoxy Matrix CFRP
Authors: Nishi Yoshitake , Uchida Helmut Takahiro , Kaneko Satoru , Faudree Michauel C.
Published: September 2019

A new method of linear connected joints (Ti/CF-plug/Epoxy) of Ti (Titanium) to Epoxy connected by CF-plug was innovated and developed, since fine carbon fibers (CFs) generate the extremely large friction force by their broad interface between metals and Epoxy polymer (M/Epoxy). Compared with glue and spontaneous adhesions of M/Glue/Epoxy and M/Epoxy, the new method remarkably improved the fracture toughness with maintaining light weight. To maintain the high joint strength of the Ti/CFW-CFJ/Epoxy, the Ni coating film on CF should control to bite the CF by molten Ti. The tensile strength (σb) and its strain (εb) of Ti/NiCFW-CFJ/Epoxy were higher than those of Ti/CFW-CFJ/Epoxy. In addition, increasing the CF-volume increases the σb. The CF-plug joint between Ti and Epoxy matrix CFRP apparently probably enhances the fuel efficiency, as well as safety level of airplane.
Properties of Porous Polyimide Films Based on Melamine Template
Authors: Ding Qing Jun , Li Hua Feng
Published: September 2019

In this paper, melamine was used as porogen to prepare porous polyimide film by in-situ polymerization. The mechanical properties, thermal properties, dielectric properties, oil content and friction and wear properties of polyimide films with different porosity were investigated. The tensile strength of porous films decreases obviously with increase of melamine content. It shows the lower thermal decomposition temperature and the faster decomposition speed compared with the non-porous film, indicating higher heat exchange rate due to holes in porous films. As the porogen content increases, the dielectric constant decreases significantly, and the film with melamine content of 20 wt.% has the lowest dielectric constant of 2.43. The holes lead to good oil storage performance and the wear rate and the friction coefficient decrease with the increase of porosity. Keywords: polyimide; porous; melamine; dielectric; friction
Anisotropy Evaluation of Different Raster Directions, Spatial Orientations, and Fill Percentage of 3D Printed PETG Tensile Test Specimens
Authors: Hanon Muammel M. , Marczis Róbert , Zsidai László
Published: September 2019

In this paper, the mechanical properties of Polyethylene terephthalate-glycol (PETG) tensile test specimens have been investigated. The test pieces were prepared using fused deposition modelling (FDM) 3D printing technology. Three print settings were examined which are: raster direction angles, print orientations, and infill percentage and patterns in order to evaluate the anisotropy of objects when employing FDM print method. The variations in stress-strain curves, tensile strength values and elongation at break among the tested samples were studied and compared. Illustration for the broken specimens after the tensile test was accomplished to know how the test pieces printed with various parameters were fractured. A comparison with some previous results regarding the elongation at break has been carried out.
Effect of Hydroentanglement on Structures and Properties of Wet-Laid Paper Sheets
Authors: Deng Chao , Jin Xian Gyu
Published: September 2019

In this work, pulp/lyocell wet-laid paper sheets have been consolidated by hydroentanglement techniques. Scanning electron microscopy has been used to evaluate the structures of wet-laid paper sheets before and after hydroentanglement. Wet tensile strength along longitudinal (preferential) and transverse directions show the effect of hydroentanglement techniques on the mechanical properties of wet-laid paper sheets. In addition, the air permeability and water absorbency properties of materials have been evaluated. The results show that the structures of wet-laid paper sheets become fluffy and fiber entanglements increase after consolidation. The wet tensile strength values of wet-laid paper sheets at the longitudinal and transverse directions are increased by 109.0% and 78.7%, respectively after hydroentanglement. The air permeability and water absorbency of wet-laid paper sheets are increased by 957.6% and 137.0%.
Non-Oriented Silicon Iron Alloys Used in Efficient Electrical Motor Production
Authors: Paltanea Gheorghe , Manescu Paltanea Veronica , Nemoianu Iosif Vasile , Gavrila Horia
Published: September 2019

In this paper four non-oriented electrical steel grades M400-50A, M400-65A, M300-35A and NO20, utilizing a laboratory single sheet tester, were analyzed. For the magnetic measurements the peak magnetic polarization of 1 T was chosen. The frequency was variated between 3 Hz and 400 Hz. The isotropic electrical steel sheets were cut through punching technology, along the rolling direction. The experimentally determined energy losses were decomposed, using the loss separation theory, into hysteresis, classical and excess components. The relative magnetic permeability was analyzed and its parts, real and imaginary permeability were computed. The non-oriented alloy magnetic properties’ variation as a function of frequency was plotted and explained in the paper.
Thermal Stability of Nanocrystalline Soft Magnetic Alloys with Different Inhibitors
Authors: Tsepelev Vladimir S. , Starodubtsev Yuri N. , Belozerov V.Ya.
Published: September 2019

In this work, the effect of different inhibitors on the thermal stability of the magnetic properties in Fe73.5Cu1M3Si13.5B9 nanocrystalline alloys, where M = Nb, W, Mo, was investigated. Nanocrystalline alloy with tungsten has the greatest thermal stability. The change in the magnetic properties in the ageing process was associated with vacancies and vacancy clusters, the formation of which is facilitated by large atoms of inhibitory elements occupying free positions in the substitution solid solution.
Study of Corrosion Behaviour of Carbon Steel in Evian Derived Solution from Electrochemical Techniques
Authors: Mjwana Phumlani , Obadele Babatunde J. , Refait Philippe , Olubambi Peter
Published: September 2019

Marine structures and buried pipelines are constantly exposed to extreme conditions with elements such as temperature variation, soil ion content and dissolved metals posing a continuous threat on the integrity and lifespan of the structures. Quantification of these elements has been limited to studying only a few of the parameters, with the resulting corrosion behaviour not fully understood. The purpose of this study was to investigate the corrosion behaviour of carbon steel in Evian derived solution using the anodic component attained from modelled polarisation curves. The behaviour of the metal/electrolyte interface was studied using a combination of voltammetry and X-ray diffraction analysis of the mineral layer. The expression for the anodic and cathodic component of the current as a function of potential was attained from log|j| vs. potential plots. Mathematical modelling of the experimental polarisation curves was done using OriginPro Data Analysis & Graphing Software. Voltammetry around open circuit potential (VAOCP) showed the necessity for corrosion protection as the adopted electrochemical system resulted in a progressively corrosive environment. Kinetics and mechanism of the anodic and cathodic process indicated corrosion processes similar to aerated soil conditions.
Synthesis and Characterization of a Polymer Matrix of Carrageenan, Chitosan and Hyaluronan on Stainless Steel 316L
Authors: Fojas Jhalique Jane , De Leon Rizalinda L.
Published: September 2019

A novel bioactive coating matrix consisting of three biopolymers – carrageenan, chitosan, and hyaluronan, was synthesized via alternate layer-by-layer (L-b-L) self-assembly of the oppositely-charged polyelectrolytes on a 316 L SS scaffold. The L-b-L deposition was carried out by substrate immersion in each polyelectrolyte solution for various length of time with 80 mins as the optimum time based on morphological non-homogeneity of coating evaluated through SEM. Co-60 γ-irradiation of the coating was done to enhance cross-linking. To test the coating matrix’s resitstance to shear stress, the coated scaffolds were subjected to agitation of 500 to 2000 rpm in phosphate buffer solution (PBS) for 24 hours. The biopolymer surface subjected to 500 rpm agitation did not exhibit noticeable surface changes and appeared similar to that of the control sample. The optimum coating was then evaluated for hemocompatibility and demonstrated low cytotoxicity with average live cell count of 77.54% after 48 hours of incubation.
Mechanical and Corrosion Behavior of Pure Aluminium Added Friction Stir Weld Joint of Aluminium Alloy
Authors: Sinhmar Sunil , Dwivedi Dheerendra Kumar
Published: September 2019

Friction stir welding (FSW) of AA2014 aluminium alloy was performed by sandwiching pure aluminium (Al) in the form of strip between the abutting surfaces. Mechanical and corrosion behavior of weld joint with and without pure aluminium addition was compared. Friction stir welding was carried out at rotational speed of 931 rpm and traverse speed of 41 mm/min. Pure aluminium strip of 1 mm thickness was used for incorporating Al in weld nugget zone. Microstructure analysis was carried out using optical microscope and FESEM with energy dispersive spectroscopy (EDS). Microhardness and tensile testing were performed on the weld joints. Corrosion behavior was investigated using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (Tafel) test. FESEM analysis was performed before and after corrosion test. Traces of pure aluminium strip were observed in the microstructure. The incorporated strip was found not to be uniformly distributed in the nugget zone. Pure aluminium addition reduced the extent of formation of the second phase particle in the nugget zone as compared to the normal FSW joint i.e. without Al addition. This metallurgical homogeneity resulted in better corrosion resistance of the Al added weld joint than the normal FSW joint.
WO3/Nb2O5 Nanoparticles-Decorated Hierarchical Porous ZnO Microspheres for Enhanced Photocatalytic Degradation of Palm Oil Mill Effluent and Simultaneous Production of Biogas
Authors: Sin Jin Chung , Chin Ying Hui , Lam Sze Mun
Published: September 2019

Conventionally, palm oil mill effluent (POME) was treated using open ponding system, which nevertheless long retention times and large treatment areas were required. In this report, heterogeneous photocatalysis was used to degrade the POME and simultaneously assessed the biogas formation. Characterization of the chemically prepared hierarchical porous ZnO microspheres showed that wurtzite was the predominant crystalline phase with a band gap energy of 3.22 eV. Moreover, the as-prepared ZnO were assembled by large numbers of interleaving nanosheets and formed an open porous structure. Under UV irradiation, the as-prepared ZnO demonstrated photocatalytic property on POME degradation. The WO3 and Nb2O5 decorated ZnO photocatalysts (WO3/ZnO and Nb2O5/ZnO) with improved photocatalytic performances were also prepared using a simple and rapid way. Significantly, in the presence of WO3/ZnO and Nb2O5/ZnO composites, the degradation of POME achieved 68.3% and 91.7%, respectively after 240 min irradiation. Interestingly, the assessment of the biogas formation showed that the photocatalytic reactions over Nb2O5/ZnO and WO3/ZnO composites generated higher amount of biogas products (CH4 + CO2) compared to that of ZnO. The photocatalytic enhancement was attributed to the high separation efficiency of photogenerated electron–hole pairs based on the formation of heterojunction structures between the WO3/Nb2O5 and ZnO. The observed findings also revealed that the photocatalytic technology using hierarchical WO3/ZnO and Nb2O5/ZnO composites had the potential to efficiently treat wastewater.
Solid State Reaction Synthesis and Characterization of Lithium Lanthanum Titanate Lithium-Ion Conducting Solid Electrolyte with Different Li to La Content
Authors: Dono Andrew , Cervera Rinlee Butch
Published: September 2019

Lithium Lanthanum Titanate, Li3xLa(2/3)-x□(1/3)-2xTiO3, with three different compositions of (i) x = 0.097 (Li0.29La0.57TiO3), (ii) x = 0.117 (Li0.35La0.55TiO3), and (iii) x = 0.167 (Li0.50La0.50TiO3) were prepared via solid state reaction synthesis sintered at 1150 °C for 36 hours. X-ray diffraction (XRD) analysis revealed that all samples can be indexed to a cubic perovskite structure with lattice parameter a of about 3.86 Å. Morphological analysis using SEM showed that the samples are relatively dense and the calculated relative density of the LLTO samples range from about 94% to as high as 99% with increasing trend as Li content increases. Room temperature conductivity and its temperature dependence up to 120 °C were investigated. LLTO sample with x =0.117 revealed the highest total ionic conductivity at room temperature of about 1.69 x 10-03 S/cm which can be a promising solid electrolyte for an all-solid-state lithium-ion batteries.
Atmospherically Stable Silver Nanowire/Hydroxyethyl Cellulose Films and their Application in Flexible Transparent Touch Screen
Authors: De Guzman Nathaniel , Balela Mary Donnabelle L.
Published: September 2019

Silver nanowires (AgNWs) has been extensively studied to replace indium tin oxide as a suitable material for transparent conducting films (TCEs) The networks of nanowires however are prone to degradation due to corrosion when exposed to ambient conditions. In this study, high aspect ratio AgNWs were synthesized with an improved polyol method by varying the reaction temperatures in the nucleation and growth stage. Solutions of AgNWs were deposited on polymer substrates and were exposed to ambient laboratory conditions for several days and the effect on the stability and overall performance of the AgNW films was investigated. Morphological and elemental analysis of the exposed films was done using SEM and EDX, respectively. Hydroxyethyl cellulose (HEC) was introduced as a polymeric binder and protective agent in order to prevent the exposure of the AgNW surface to corrosive agents in air. A TCE with a sheet resistance of 47.50 Ω/sq and transmittance of 89.70% at 550 nm without any harsh post-treatments, was demonstrated. These electrodes were used to fabricate a transparent flexible touch screen.
Flexural Vibration Attenuation Properties of Phononic Crystals
Authors: Ghachi Ratiba F. , Alnahhal Wael I. , Haque A.B.M. Tahidul , Shim Jong Min , Aref Amjad
Published: September 2019

Phononic crystals (PCs) have the ability to have phononic bandgaps dependent on the acoustic properties of its constituent materials (i.e., mass, elasticity). Forming a 1D periodic variation using a viscoelastic material allow the PC to have more wave vibration attenuation in the longitudinal direction. In this study, the low transmission zones and the vibration attenuation properties of a one-dimensional PC subjected to flexural vibration was evaluated experimentally. Results were presented in the form of frequency response functions and showed the flexural low-frequency zones starting at 500 Hz with three zones in the 16kHz range.
Influence of B2O3 on Dielectric, Mechanical, and Thermal Properties of MgO-Al2O3-SiO2 Glass-Ceramics
Authors: Li Bo , Jing Ke , Bian Hai Bo
Published: September 2019

Low temperature sintered MgO-Al2O3-SiO2 glass-ceramic with high mechanical and low thermal expansion was prepared for package. The remarkable influence of B2O3 addition on the electrical, mechanical, and thermal properties was fully investigated. A small amount of B2O3 promoted the sintering process and improved the densification of MAS. The kinetics via Kissinger method indicated that an appropriate B2O3 content decreased the activation energy and helped the occurrence of crystallization. Due to the increase of crystallinity and indialite phase, B2O3 addition significantly enhanced flexural strength and Young’s modulus. MAS doped with 3wt% B2O3 can be sintered at 900 °C and obtained good properties: σ = 229 MPa, φ = 86 GPa, α = 1.66×10-6 /°C, εr = 5.29, and tanδ = 5.9×10-4.
Effect of Heating Rate on the Microstructure and Mechanical Properties of Spark Plasma Sintered CNTs Reinforced Nickel Aluminide
Authors: Ayodele Olusoji Oluremi , Awotunde Mary Ajimegoh , Shongwe Mxolisi Brendon , Adegbenjo Adewale Oladapo , Babalola Bukola J. , Obadele Babatunde J. , Olubambi Peter Apata
Published: September 2019

Powder metallurgy method was used to consolidate nickel aluminide reinforced multi-walled carbon nanotubes through planetary ball mill in order to facilitate the effective dispersion of carbon nanotubes (CNTs). In this investigation, 0.5 wt% of CNTs was added to the powder mixture of nickel and aluminum through two ball milling processes: low energy ball mill (LEBM) and high energy ball mill (HEBM). The bulk composites were synthesized by spark plasma sintering (SPS) at constant temperature, holding time, pressure of 32 MPa, 800 °C and 5 min respectively. The heating rate was varied between 50 and 150 °C/min. Microstructural evolutions of the composites were studied and densification of the composites was improved with increase in heating rate but depreciated as the heating rate was further increased. Vickers microhardness values of the fabricated composites were enhanced with increase in heating rate.
Stability Analysis of Cylindrical Shells Resting on Winkler Elastic Foundation Using Semi-Analytical Quadrature Element Method
Authors: Hu Qi Gao , Hu Xu Dong , Shen Zhi Qiang , Tao Liang Yun , Tan Ze
Published: September 2019

The buried pipelines or vessels and other similar structures made of homogeneous or advanced composite materials are commonly used in civil engineering and biotechnology. The radial stability problem of these structures was widely studied using the cylindrical shell model over the past years. In this paper, the linear stability of cylindrical shells resting on Winkler elastic foundation under uniformly distributed external pressure was analyzed with semi-analytical quadrature element method (QEM). As for the longitudinal direction, the radial deflection of shell was approximated by the quadrature element formulation. While the analytic trigonometric function was adopted for description of radial deflection in circumferential direction. The Numerical results of critical buckling load were compared with the semi-analytical FEM. It is found that the semi-analytical QEM possesses higher computational efficiency and applicability than semi-analytical FEM. Then, the effects of the shell length, radius, and thickness on the critical buckling pressures are systematically investigated through the parametric studies.
Effect of Dipotassium Hydrogen Phosphate and Calcium Nitrate on Strength and Microstructural Properties of Geopolymer Mortar
Authors: Rahman Norbaizurah , Ismail Amalina Hanani , Kusbiantoro Andri
Published: September 2019

Adoption of coal fly ash (Class C) as the main source material for geopolymers would cause rapid setting to the fresh geopolymer mortar or concrete. This behaviour explained the limited application of this material in the construction industry. On the other hand, calcium nitrate (Ca (NO3)2) and dipotassium hydrogen phosphate (K2HPO4) are alternative admixtures that known to extend the setting time of fresh geopolymers. However, their effect on the strength and microstructural properties remain unclear due to the limitation of relevant literature from previous studies. Therefore, this study aims to investigate the effect of these admixtures in fly ash based geopolymer system, particularly to its strength performance. The effects of adding Ca (NO3)2 and K2HPO4 were evaluated at dosages of 0.5%, 1.5%, and 2.5% (by fly ash weight) in the geopolymer mixture, and samples were cured at room temperature. Hardened geopolymer specimens were measured for their compressive strength, porosity, and microstructural characteristic. The inclusion of 0.5% of alternative chemical reagents was found as the optimum proportion and able to enhance the compressive strength of the geopolymer mixtures. However, efflorescence was detected on the surface of the hardened specimen when K2HPO4 was included in its mixture. This phenomenon is influenced by the presence of monovalent and trivalent anions in the system namely nitrates and phosphates. In this study, each anion had a particular role in each stage of geopolymerisation, and determined the quality via crystal growth control and influenced the development of aluminosilicate structures.
Compressive Strength Variations in Lightweight Aggregate Concrete Samples Affected by Segregation Caused by Excessive Vibration
Authors: Solak Afonso Miguel , Tenza-Abril Antonio José
Published: September 2019

Lightweight aggregates used in lightweight aggregate concrete (LWAC) exert an important influence on the compressive strength and elastic modulus of concrete. A good homogeneity of the material is essential in this type of concrete once a non-uniform distribution of aggregates in the mixture may strongly affect the concrete global properties, which are commonly considered as homogenous values for design purposes. LWAC, due to density differences among its components, are susceptive to segregation. The separation of the aggregates from the rest of the mixture increases the risk of cracking and areas where segregation or insufficient compaction occur are mostly the areas where the concrete failure begins. The aim of this study is analysing possible variations caused by segregation on compressive strength (fc) along the height of cylindrical samples, comparing results of four sections extracted from samples segregated intentionally.
Tensile Test Method for Basalt Roving
Authors: Stupishin Leonid U. , Emelyeanov S.G. , Savelyeva E.V. , Altuhov F.V.
Published: September 2019

In the construction industry there is no method for tensile testing of materials of basalt complex filaments of small diameters and roving. The existing methods of testing fibers and roving presented in regulatory documents are intended for textile materials and materials based on fiberglass. The studies cited in the article were aimed at studying the strength properties of roving materials and a multifilament yarn based on basalt fibers, as well as working out methods for testing them. The article presents studies of the strength characteristics of roving and complex yarn based on basalt fiber, on which testing of basalt material samples was tested. The strength characteristics of various forms of basalt materials for various adhesive processing were obtained. The applied experimental test procedure was appreciated positively.
Energy Savings of PCM-Incorporated Building in Hot Dry Climate
Authors: Sovetova Meruyert , Memon Shazim Ali , Kim Jong
Published: September 2019

Phase change materials is one of the innovative technologies to reduce the heating and cooling demand of buildings. In this research, the thermal performance and energy efficiency of PCM-incorporated residential house located in Sharjah and Al-Ain cities using DesignBuilder software have been evaluated. According to the simulation results, for both cities PCM 32 was found to be the most effective with energy consumption reduction around 19%. The optimum PCM decreased the maximum temperature by up to 1.09°C and was able to reduce temperature fluctuations. For constant volume, the influence of different thicknesses and surface area on energy savings was evaluated and it was found that energy savings increased with the increase in surface area and decrease in thickness of PCM layer. Finally, from correlation analysis, it was found that relationship between energy savings and meteorological factors like wind speed, temperature, relative humidity and solar radiation exist.
Connection Performance of Bolted Aluminum Alloy Honeycomb Panel-Beam Composite Structure
Authors: Gu Ye , Zhao Cai Qi , Yang Yong , Zhao Wei Ran
Published: September 2019

A convenient and reliable connection between panels and beams was investigated for collaborative work of single-layer composite reticulated shell structure in which aluminum alloy honeycomb panels participate. In the paper, the "self-tapping bolt" connection was adopted to realize the "tight fit" performance of connection effectively in the composite structure. Through three groups of bearing capacity test on 1.5 m×3 m square meters of the aluminum alloy honeycomb panel-square tube beam combined structure, the force characteristics and failure mechanism of the structures were studied. The experimental results revealed that the connection method could ensure effective transmission between the panel and the beam which made them work in excellent condition. In order to simulate complex performance connection with the panel-beam composite structure, tangential and normal contact behavior were considered at the bolt connection point between the honeycomb panel and the beam in ABAQUS analysis. The analysis results illustrated that the finite element results had the highest matching degree with the experimental values when the friction coefficient of the joint boundary was 0.25. The finite element analysis of the connection bolts spacing indicated that the economic and excellent connection effect can be achieved when the spacing was about 90 mm.
Enhancing Dispersion of Silica Nanoparticles with Ammonium Laurate Surfactant for Natural Rubber Latex Composites
Authors: Seangyen Wichudaporn , Prapainainar Paweena , Sae-Oui Pongdhorn , Loykulnant Surapich , Dittanet Peerapan
Published: September 2019

In-situ silica nanoparticles with ammonium laurate surfactant in natural rubber latex composites were characterized to describe the reinforcement mechanism in enhanced mechanical properties. In-situ sol-gel method was introduced to generate silica nanoparticles in natural rubber latex using a mole ratio of water-to-TEOS of 28.9 stirring at room temperature for 24 hours. The addition and effect of adding ammonium laurate surfactant for enhancing dispersion and compatibility between silica nanoparticles and rubber matrix was also studied. The natural rubber latex was then vulcanized by electron beam radiation at 200 kGy. The silica content in rubber composites made in-situ, was analyzed by TGA, showed an increase from 3.08 phr to 8.92 phr, corresponding to addition of TEOS amounts of 10 phr to 30 phr, respectively. The dispersion of silica nanoparticles in rubber matrix with ammonium laurate surfactant was improved and exhibited less aggregation than rubber composites absent of ammonium laurate surfactant as evidenced by SEM-EDX. The increase of silica content in rubber composites exhibited lower swelling ratio and higher crosslink density when compared with neat natural rubber. Also, the modulus at 100% and 300% strain also increased with increasing silica nanoparticles incorporation in contrast to tensile strength.
A Nanoindentation Study on Al (TiFe-Mg-SiC) Composites Fabricated via Stir Casting
Authors: Akinwamide Samuel Olukayode , Lemika Serge Mudinga , Obadele Babatunde J. , Akinribide Ojo Jeremiah , Falodun Oluwasegun Eso , Olubambi Peter Apata , Abe Bolanle Tolulope
Published: September 2019

The limitations of aluminium in most engineering applications has led to the development of aluminium matrix composites with improved microstructural and mechanical properties. Nanoindentation techniques was used in assessing the mechanical properties of fabricated aluminium matrix composites with ferrotitanium and silicon carbide as reinforcements. Results from nanoindentation experiments shows the dependence of modulus of elasticity, microhardness and contact depth on the dispersion of ferrotitanium and silicon carbide reinforcements within the aluminium matrix. Highest nanohardness value was observed in composite with 7 wt. % silicon carbide, while the lowest elastic modulus was recorded in as-cast aluminium. Further analysis of specimens confirmed a decrease in maximum penetration depth with respective increase in the addition of silicon carbide reinforcements in the fabricated composites.
Effect of Polyethylene Glycol in Nanocellulose/PLA Composites
Authors: Somphol Wanasorn , Lampang Thipjak Na , Prapainainar Paweena , Sae-Oui Pongdhorn , Loykulnant Surapich , Seubsai Anusorn , Dittanet Peerapan
Published: September 2019

Poly (lactic acid) or PLA was reinforced by nanocellulose and polyethylene glycol (PEG), which were introduced into PLA matrix from 0 to 3 wt.% to enhance compatibility and strength of the PLA. The nanocellulose was prepared by TEMPO-mediated oxidation from microcrystalline cellulose (MCC) powder and characterized by TEM, AFM, and XRD to reveal rod-like shaped nanocellulose with nanosized dimensions, high aspect ratio and high crystallinity. Films of nanocellulose/PEG/PLA nanocomposites were prepared by solvent casting method to evaluate the mechanical performance. It was found that the addition of PEG in nanocellulose-containing PLA films resulted in an increase in tensile modulus with only 1 wt% of PEG, where higher PEG concentrations negatively impacted the tensile strength. Furthermore, the tensile strength and modulus of nanocellulose/PEG/PLA nanocomposites were higher than the PLA/PEG composites due to the existence of nanocellulose chains. Visual traces of crazing were detailed to describe the deformation mechanism.
Synthesis of Natural Composite of Natural Rubber Filling Chitosan Nanoparticles
Authors: Petchsoongsakul Thidarat , Dittanet Peerapan , Loykulnant Surapich , Kongkaew Chaveewan , Prapainainar Paweena
Published: September 2019

Mechanical properties of natural rubber composite were improved by adding chitosan nanoparticles in this work. The chitosan nanoparticles were prepared by ionotropic gelation method. The effect of chitosan nanoparticle content in natural rubber at 0, 3, 6 and 9 phr were studied. Size of the synthesized chitosan nanoparticles was 282 ± 96 nm. Natural rubber vulcanization was by electron irradiation at intensity 200 kGy. The morphology of composite was investigated by scanning electron microscopy (SEM). The mechanical properties (tensile strength and modulus) were determined by tensile testing. The interaction of filler-rubber was illustrated by Fourier transform-infrared (FTIR) and dynamic mechanical analysis (DMA). It was found that chitosan nanoparticles was well dispersed within natural rubber matrix. The optimum filler content was affected to mechanicals properties of natural rubber composites. The chitosan nanoparticles at 3 phr in natural rubber composites was found to have the highest mechanical properties. The dispersion and immobilization of chitosan nanoparticles at 3 phr was the best among all loading. In addition, 3 phr chitosan nanoparticles / natural rubber composite had filler-rubber higher interaction than those of other loading.
Presence of N-acetylgalactosamine/galactose residues on bronchioloalveolar cells during rat postnatal development
Authors: Martins Maria de Fátima , Martins Paula , Gonçalves Carlos Alberto
Published: September 2019

In mammals, the alveolarization process develops predominantly after birth. Airway cells display a complex assemblage of glycans on their surface. These glycans, particularly terminal glycan extensions, are important effective carriers of information that change during the differentiation process. Nevertheless, few systematic data are reported about the cell surface sugar residue content during post-natal lung development. In the present work, we aimed to identify and semi-quantify N-acetylgalactosamine (GalNAc)/galactose (Gal) residues on the bronchioloalveolar cell surface in rat lung sections from 1-, 4-, 8- day old and adult animals and link these data with the lung glycocalyx composition. Horseradish peroxidase-conjugated lectin from Glycine max (soybean agglutinin, SBA) was used, and light microscopy methodologies were performed. SBA labelling intensity was studied before and after sialidase pre-treatment, at one-, four- and eight-day-old animals and adult animals. For semi-quantitative evaluation of SBA binding intensity, two investigators performed the analysis independently, blinded to the type of experiment. Reactivity of the lectin was assessed in bronchiolar and respiratory portion/alveolar epithelial cell surfaces. We evidenced a stronger positive reaction when lung sections were pre-treated with neuraminidase before incubation with the lectin in one- and four-day-old animals and adult animals. These results were not so manifest in eight-day-old animals. This binding pattern, generally points towards the presence of terminal but mainly sub-terminal GalNAc/Gal residues probably capped by sialic acids on the rat bronchiolar/respiratory tract epithelial cells. As this glycan extension is common in O- and N-glycans, our results suggest that these glycan classes can be present in bronchioloalveolar cells immediately after birth and exist during the postnatal period. The results observed in eight-day-old rat lung sections may be due to the dramatic lung morphologic changes and the possible underlying biological mechanisms that occur during this age-moment.
Error propagation approach for estimating root mean square error of the reference evapotranspiration when estimated with alternative data
Authors: Ganji Homayoon , Kajisa Takamitsu
Published: September 2019

Estimation of reference evapotranspiration (ET0) with the Food and Agricultural Organisation (FAO) Penman-Monteith model requires temperature, relative humidity, solar radiation, and wind speed data. The lack of availability of the complete data set at some meteorological stations is a severe restriction for the application of this model. To overcome this problem, ET0 can be calculated using alternative data, which can be obtained via procedures proposed in FAO paper No.56. To confirm the validity of reference evapotranspiration calculated using alternative data (ET0(Alt)), the root mean square error (RMSE) needs to be estimated; lower values of RMSE indicate better validity. However, RMSE does not explain the mechanism of error formation in a model equation; explaining the mechanism of error formation is useful for future model improvement. Furthermore, for calculating RMSE, ET0 calculations based on both complete and alternative data are necessary. An error propagation approach was introduced in this study both for estimating RMSE and for explaining the mechanism of error formation by using data from a 30-year period from 48 different locations in Japan. From the results, RMSE was confirmed to be proportional to the value produced by the error propagation approach (ΔET0). Therefore, the error propagation approach is applicable to estimating the RMSE of ET0(Alt) in the range of 12%. Furthermore, the error of ET0(Alt) is not only related to the variables’ uncertainty but also to the combination of the variables in the equation.
Development of a new washing machine in olive oil extraction plant: A first application of usability-based approach
Authors: Cappelli Alessio , Parretti Chiara , Cini Enrico , Citti Paolo
Published: September 2019

This paper suggests an approach based on usability engineering, used to assess the usability of machines and plants in the agrofood industry, aiming to enhance machines efficacy, efficiency and safety with a development focused on users’ needs. Furthermore, the article examines the validation of the suggested approach through its application in a case study regarding a washing machine for the production of extra virgin olive oil. Firstly, it was necessary to identify the target cluster. For this reason, only Tuscan high quality extra virgin olive oil manufacturers were selected. The selected producers are of between 30 and 65 years old, with working experience in the field of at least 10 years. Once the cluster was identified, through brainstorming, the critical phases of the process were identified. According to the results, the washing process was considered the most critical phase. The reached conclusions were analysed and translated into technical aspects through the Quality Function Deployment. The predominant needs to be introduced in the new washing machine were related to the reduction of processing time, the improvement of washing system, the reduction of water consumption, and the increase of worker safety. Successively, a virtual prototype was developed and tested with 8 experts. Afterwards, a usability test was performed with 15 users. Two different olive washing machines were evaluated (traditional vs new machine). The Wilcoxon signed-rank test was utilised for users’ scores interpretation. According to P-values (ranging from P<0.001 to P=0.008) several statistically significant differences emerged between the two washing machines. In particular, remarkable differences regarding efficacy, efficiency, usability, human-machine interaction, reliability and an increase in safety were highlighted. Moreover, the results indicate that the new washing machine is overall perceived as more usable machine. In conclusion, the results are encouraging and give robustness both to the proposed methodological approach and to the improvement of the new washing machine.
Depression and heart failure: an intricate relationship
Authors: Aloisi Gaetano , Zucchelli Alberto , Aloisi Bruno , Romanelli Giuseppe , Marengoni Alessandra
Published: September 2019

In patients with heart failure (HF), depression is common and associated with adverse outcomes such as reduced adherence to treatment, poor quality of life, increased hospitalizations and elevated mortality. Despite these adverse impacts, depression remain underdiagnosed in HF patients. We performed a target review of the literature to identify the association between HF and depression, to examine the mechanisms that link these two conditions and to identify instruments for an accurate diagnosis and treatment of depression in HF patients. Depression is associated with the development and progression of HF, including increased rates of mortality, mediated by behavioral and pathophysiological mechanisms. The overlap of symptoms between depression and HF often makes the diagnosis of depression difficult and late. Currently, specific guidelines for depression screening in HF patients are lacking, partly because evidences showing that depression screening improves cardiac outcomes are insufficient. European guidelines suggest the early use of instruments such as the Beck Depression Inventory (BDI) and the Geriatric Depression Scale (GDS), both characterized by accuracy and administration simplicity. There is limited evidence of pharmacological treatment and psychotherapy efficacy in patients with HF. However, cognitive-behavioral therapy has been shown to improve outcomes HF patients, and selective serotonin reuptake inhibitors appear safe in this cohort.
Omics-based insights into therapy failure of pediatric B-lineage acute lymphoblastic leukemia
Authors: Alsagaby Suliman A.
Published: September 2019

B-lineage acute lymphoblastic leukemia (B-ALL) is the most common type of cancer seen in children and is characterized by a variable clinical course. Although there have been remarkable improvements in the therapy outcomes of pediatric B-ALL, treatment failure remains the leading-cause of death in 18% of the afflicted patients during the first 5 years after diagnosis. Molecular heterogeneities of pediatric B-ALL play important roles as determinants of the therapy response. Therefore, many of these molecular abnormalities have an established prognostic value in the disease. The present review discusses the omics-based revelations from epigenomics, genomics, transcriptomics and proteomics about treatment failure in pediatric B-ALL. Next it highlights the promise of the molecular aberration-targeted therapy to improve the treatment outcomes.
Geographical distribution of cervical cancer in Odisha: A 5-year retrospective study at a regional cancer center
Authors: Hota Pradeep Kumar , Panda Niharika , Nayak Bhagyalaxmi , Samantaray Sagarika
Published: September 2019

Background: Cancer cervix and breast are the two major female health problems in India. A hospital-based, 5-year (2010–2014) retrospective study was conducted at a regional cancer center of Odisha to analyze the present burden of cancer cervix in this state, which has a population of more than 45.5 million at present. Materials and Methods: All the patients suffering from cancer cervix that was treated by radiotherapy during 2010–2014 at this center were analyzed year wise for age, stage of disease, and native area. Results: Based on the Census 2011 data, it was calculated and found that from the low-literacy area on an average of 4.62 cervical cancer patients per million, from the medium-literacy area 6.56 patients per million, and from high-literacy area 19.11 patients per million of population have received radiotherapy in this hospital. More than 60% of patients with cervical cancer were from stage IIIB and in the age group of 50–55 years. Discussion: Odisha has 83.7% female population in rural areas with literacy rate below 50%. Due to lack of awareness and unavailability of cancer care facilities at their reach, they mainly depend on various alternative medicines in unscientific manner for their health care. Conclusion: Strengthening of existing regional cancer center, development of oncology wings in all medical college hospitals by providing basic radiotherapy facilities, emphasizing more on district cancer control programs, decentralizing of NGO schemes, and facilitating with more cancer screening and awareness programs may help better registration, prevention, and treatment of cancer in Odisha.