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Search results for: WEIGHT OPTIMIZATION
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Studies on applicability of new solid-phase microextraction fibers for the selective extraction and determination of short - chain monocarboksylic acids
PublicationShort-chain monocarobxylic acids, sometimes referred to as volatile fatty acids (VFA), are a group of low molecular weight alkyl monocarboxylic acids that are widely distributed within the environment. These molecules contain any from 2 to 8 carbon atoms and originate from the anaerobic biodegradation of organic matter such as carbohydrates, proteins, and fats. These compounds are commonly found in the effluents from animal farming,...
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LC-MS and LC-NMR as Complementary Techniques for the Determination of Pharmaceuticals in Dosage Formulations
PublicationPharmaceuticals contain not only pharmacologically active compounds but also a range of excipients. The danger exists that impurities may also be present in such drugs, which may adversely affect their efficacy and even endanger patient health and life. Monitoring the composition of pharmaceutical products is therefore essential. The trace amounts of such impurities in pharmaceuticals are often identified and determined with liquid...
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Digestive system, femur and tibia bone characteristics of Dworka and Pekin ducks
PublicationThe aim of this study was to determine traits of the digestive system and femur and tibia bone ofDworka and Pekin ducks. A study was conducted on 24 Dworka duck (breeding strain D11) carcassesand 24 Pekin duck (conservative strain P9) carcasses, 12 male carcasses and 12 female carcassesfrom each strain. The lengths of the intestinal segments were tape measured. The diameters of theintestinal segments and leg bone dimensions...
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Digestive system, femur and tibia bone characteristics of Dworka and Pekin ducks
PublicationThe aim of this study was to determine traits of the digestive system and femur and tibia bone ofDworka and Pekin ducks. A study was conducted on 24 Dworka duck (breeding strain D11) carcassesand 24 Pekin duck (conservative strain P9) carcasses, 12 male carcasses and 12 female carcassesfrom each strain. The lengths of the intestinal segments were tape measured. The diameters of theintestinal segments and leg bone dimensions...
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Digestive system, femur and tibia bone characteristics of Dworka and Pekin ducks
PublicationThe aim of this study was to determine traits of the digestive system and femur and tibia bone ofDworka and Pekin ducks. A study was conducted on 24 Dworka duck (breeding strain D11) carcassesand 24 Pekin duck (conservative strain P9) carcasses, 12 male carcasses and 12 female carcassesfrom each strain. The lengths of the intestinal segments were tape measured. The diameters of theintestinal segments and leg bone dimensions...
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The effect of polyamide PA12 and polyester PBT blocks' lengths on the structure and propertries of multiblock terpoly(amide-block-ester-block-amide) (TPAEA)
PublicationThe ternary multiblock system terpoly(amide-b-ester-b-amide) (TPAEA) of the chemical structure: poly[(oligoamide-6.36)-block-(tetramethylene terephthalate)-block-laurolactam)] -(PA6.36-b-PBT-b-PA12)n- has been obtained (Table 1). In this system the third component (PBT block here), characterized with the proper molecular weight, is dissolved in hard phase of PA12 blocks and partially dissolved in soft phase of PA6.36. The effects...
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Modification of thermal and rheological characteristics of bitumen by waste PET/GTR blends
PublicationWaste poly(ethylene terephthalate) (wPET)/ground tire rubber (GTR) blends with variable compositions were applied as low-cost modifiers into bitumen and their performance has been evaluated via morphological, thermal and rheological analyses. Depending on the weight ratio of wPET/GTR, dispersion of single/composite domains of waste polymers in the bitumen has promoted the interaction between bitumen and blend components. Fourier...
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Implementation of Weigh-in-Motion System in Freight Traffic Management in Urban Areas
PublicationThe article presents how the Weigh-in-Motion system can be used for managing Gdynia’s freight traffic. Potential sites for weight pre-selection were identified in an analysis of the technical and location conditions. Situated directly in the east part of the Port of Gdynia a site was selected for a pilot implementation. Theoretical scenarios were simulated using an extended WIM system as a tool for controlling access to selected...
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Manufacturing of Lightweight Aggregates as an Auspicious Method of Sewage Sludge Utilization
Publication: Sewage sludge is a high-volume and low-cost waste commonly generated worldwide, so its utilization is a vital issue. The application of this waste in the manufacturing of lightweight aggregates was investigated. The process was performed using intensive mixers with volumes of 5 and 30 L, as well as the industrial 500 L mixer. Then, granulates were sintered in a tube furnace. The influence of composition and mixer size on the...
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Examination of fresh water chemistry in maritime Antarctica during austral summer 2017
PublicationDue to the fact that Antarctica is one of the least polluted places on Earth, it is a perfect place to observe the spread of global pollution. Therefore, research conducted on this continent is important due to the possibility of investigating the type of pollution and their way of transport. This work considers presence of organic contaminants in Maritime Antarctica in unexplored until now, Lions Rump headland. Qualitative and...
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Design and Evaluation of the Platform for Weight-Shifting Exercises with Compensatory Forces Monitoring
PublicationDetails of a platform for the rehabilitation of people with severe balance impairment are discussed in the paper. Based upon a commercially available static parapodium, modified to fit force sensors, this device is designed to give a new, safe tool to physiotherapists. It is designed for the patients who cannot maintain equilibrium during a bipedal stance and need to hold to or lean on something during the rehabilitation. Visual,...
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A family of new generation miniaturized impedance analyzers for technical object diagnostics
PublicationThe paper presents the family of three analyzers allowing to measure impedance in range of 10 ohm<|Zx|<10 Gohm in a wide frequency range from 10 mHz up to 100 kHz. The most important features of the analyzers family are: miniaturization, low power consumption, low production cost, telemetric controlling and the use of impedance measurement method based on digital signal processing DSP. The miniaturization and other above mentioned...
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Preparation and characterization of porous scaffolds from chitosan-collagen-gelatin composite
PublicationNovel porous scaffolds composed of chitosan, collagen and gelatin were prepared and characterized. For preparing scaffolds gelatin and collagen isolated from fish skins with various physicochemical properties were used. In order to reduce preparation solubility glutaraldehyde in the amount of 1%, w/w relative to the total biopolymers weight in solution was used. All obtained biomaterials showed a homogeneous porosity. Protein polymer...
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EFFECT OF NANOFLUID CONCENTRATION ON TWO-PHASE THERMOSYPHON HEAT EXCHANGER PERFORMANCE
PublicationAn approach – relaying on application of nanofluid as a working fluid, to improve performance of the two-phase thermosyphon heat exchanger (TPTHEx) has been proposed. The prototype heat exchanger consists of two horizontal cylindrical vessels connected by two risers and a downcomer. Tube bundles placed in the lower and upper cylinders work as an evaporator and a condenser, respectively. Distilled water and nanofluid water-Al2O3...
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Assessment of the impact of bacteria Pseudomonas denitrificans, Pseudomonas fluorescens, Bacillus subtilis and yeast Yarrowia lipolytica on commercial poly(ether urethanes)
PublicationThe assessment of the impact of the bacteria Pseudomonas denitrificans, Pseudomonas fluorescens, Bacillus subtilis and yeast Yarrowia lipolytica on commercial poly(ether urethanes) Tecoflex® and Tecothane® is presented. The polyurethane samples were incubated with pure cultures of the microorganisms at 30 °C for five months. The changes in the chemical structure of the polymers were evaluated using loss of weight and contact angle...
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Modelling Wetland Growing Season Rainfall Interception Losses Based on Maximum Canopy Storage Measurements
PublicationThis study estimates rainfall interception losses from natural wetland ecosystems based on maximum canopy storage measurements. Rainfall interception losses play an important role in water balance, which is crucial in wetlands, and has not yet been thoroughly studied in relation to this type of ecosystem. Maximum canopy storage was measured using the weight method. Based on these measurements, daily values of interception losses...
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Vegetable derived-oil facilitating carbon black migration from waste tire rubbers and its reinforcement effect
PublicationThree dimensional chemically cross-linked polymer networks present a great challenge for recycling and reutilization of waste tire rubber. In this work, the covalently cross-linked networks of ground tire rubber (GTR) were degraded heterogeneously under 150 °C due to the synergistic effects of the soybean oil and controlled oxidation. The degradation mechanism was discussed using Horikx theory and Fourier transformation infrared...
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One year performance evaluation of low volume road with cold recycled base course on the basis of FWD and Dynamic Modulus tests
PublicationArticle presents results of assessment of performance of trial section of flexible pavement with cold recycled base constructed on low volume road within typical contract conditions. Performance evaluation was made based on Falling Weight Deflectometer (FWD) test performed during construction stage – 2 times on the top of cold recycled base course – 28 and 180 days after compaction of base course and 2 times on the top of the wearing...
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OPERATING CONDITIONS OF SLIDE BEARINGS OF MILLS USED IN KGHM POLSKA MIEDŹ S.A.
PublicationThe paper contains the results from a tec hnical analysis of the conditions of the operation of hydrodynamic bearings supporting the drums of ore processing mills at KGHM Polska Mied ź S.A. A theoretical analysis was performed on the grounds of onsite examination and measurem ents of principal dimensions of the bearings of interest. The computer simulation covered the characteristics of the oil film in the bearings...
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Benefit of the doubt approach to assessing the research performance of Australian universities
PublicationThis paper proposes a benefit of the doubt (BoD) approach to assess the research performance of 37 public Australian universities based on data from 2015. The primary activities of Higher Education institutions are teaching and research, but the prestige of a university depends mainly on the results of its research activities. The BoD method is rooted in the data envelopment analysis methodology, which enables the flexible and...
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Additive Manufacturing as a Solution to Challenges Associated with Heat Pipe Production
PublicationThe aim of this review is to present the recent developments in heat pipe production, which respond to the current technical problems related to the wide implementation of this technology. A novel approach in HP manufacturing is to utilise hi-tech additive manufacturing techniques where the most complicated geometries are fabricated layer-by-layer directly from a digital file. This technology might be a solution to various challenges...
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EXPERIMENTAL AND NUMERICAL INVESTIGATION ON SPECIMEN GEOMETRY EFFECT ON THE CTOD VALUE FOR VL-E36 SHIPBUILDING STEEL
PublicationThere are special cases in the marine industry, where additional material tests, such as the fracture toughness test, must be performed. Additional fracture toughness tests, such as CTOD (Crack Tip Opening Displacement), are typically performed on three-point bend specimens. The dimension that defines all the specimen dimensions is the thickness of the material to be tested. It is recommended by classification societies (e.g. DNVGL)...
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Effect of modified soybeen oil amount on rheological characteriza-tion of polyurethane pre-polymers
PublicationPolyurethanes (Pu’s) are the polymeric materials which have got urethane groups in the structure. The properties of Pu’s depend both on the method of preparation and monomers used. Polyurethanes are produced by two methods known as one step or two step method called as “pre-polymers method”, especially for the case of segmented polyurethanes (SPU’s). These materials are thermoplastic block copolymers of the (AB)n type consisting...
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Analytical methodologies for determination of artificial sweeteners in foodstuffs- a review
PublicationArtificial high-intensity sweeteners are more and more frequently used for food production. Food industry tends to highlight beneficial aspects of their use, such as tooth-friendliness, rising-up quality of life of those suffering from different forms of diabetes and possibility of weight control without sacrificing favorite unhealthy drinks or snacks. On the other hand some of the consumers are deeply concerned about safety of...
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Pool Boiling of Water–Al2O3 and Water–Cu Nanofluids Outside Porous Coated Tubes
PublicationThis paper deals with pool boiling ofwater–Al2O3 and water–Cu nanofluids on porous coated, horizontal tubes. Commercially available stainless-steel tubes having 10 mm outside diameter and 0.6 mm wall thickness were used to fabricate a test heater. Aluminum porous coatings 0.15 mm thick with porosity of about 40% were produced by plasma spraying. A smooth tube served as a reference tube. The experiments were conducted under different...
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Application of probabilistic tools to extend load test design of bridges prior to opening
PublicationLoad tests of bridges are widely performed in a large number of countries. Deterministic comparison of measurement results to the theoretical, FEM (finite element method)-based outcomes with possible further calibration is mostly applied. Sometimes, the data collected in the tests are also used to calibrate the reliability factors of bridge structures or their components. This work proposes to complement the stage of the load test...
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Copolymerization of Styrene and Pentadecylphenylmethacrylate (PDPMA): Synthesis, Characterization, Thermomechanical and Adhesion Properties
PublicationThe copolymerization of styrene (St) with a bioderived monomer, pentadecylphenylmethacrylate (PDPMA), via atom transfer radical polymerization (ATRP) was studied in this work.The copolymerization reactivity ratio was calculated using the composition data obtained from1HNMR spectroscopy, applying Kelen-Tudos and Finemann-Ross methods. The reactivity ratio of styrene (r1=0.93) and PDPMA (r2=0.05) suggested random copolymerization...
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Soft Sensor Application in Identification of the Activated Sludge Bulking Considering the Technological and Economical Aspects of Smart Systems Functioning
PublicationThe paper presented the methodology for the construction of a soft sensor used for activated sludge bulking identification. Devising such solutions fits within the current trends and development of a smart system and infrastructure within smart cities. In order to optimize the selection of the data-mining method depending on the data collected within a wastewater treatment plant (WWTP), a number of methods were considered, including:...
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A Low-Profile 3-D Printable Metastructure for Performance Improvement of Aperture Antennas
PublicationIn order to increase the radiation performance of aperture-type antennas, this paper demonstrates a low-profile, planar, single-layer, three-dimensional (3-D) printable metastructure. The proposed hybridized metastructure is highly transparent as it is made out of novel hybrid meta-atoms having transmission coefficient magnitudes greater than -0.72 dB and fully complies with the near-field phase transformation principle. The hybridized...
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Hyaluronic acid/tannic acid films for wound healing application
PublicationIn this study, thin films based on hyaluronic acid (HA) with tannic acid (TA) were investigated in three different weight ratios (80HA/20TA, 50HA/50TA, 20HA/80TA) for their application as materials for wound healing. Surface free energy, as well as their roughness, mechanical properties, water vapor permeability rate, and antioxidant activity were determined. Moreover, their compatibility with blood and osteoblast cells was investigated....
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Emulsifying blends based on natural fats for eco-design of O/W emulsions
PublicationEmulsifier blends are most often used to stabilize and modulate the properties of cosmetic and pharmaceutical emulsions, such as skin care or application-related consistency. However, the rational design of such emulsifier blends is often not well understood, especially when their ingredients are natural raw materials. This study aimed to analyze the influence of natural fatty ingredients selected as emulsifiers on the emulsion...
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Bioactive and biodegradable cotton fabrics produced via synergic effect of plant extracts and essential oils in chitosan coating system
PublicationFunctional antibacterial textile materials are in great demand in the medical sector. In this paper, we propose a facile, eco-friendly approach to the design of antibacterial biodegradable cotton fabrics. Cotton fiber fabrics were enhanced with a chitosan coating loaded with plant extracts and essential oils. We employed Fourier-transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS), UV–Vis spectrophotometry, optical...
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Problems with modelling the strength properties of sailing vessels rigging ropes
PublicationThis article presents the basic parameters of soft ropes: natural fibre ropes, soft wire ropes and synthetic fibre ropes used for running rigging. There are only several materials still used for the production of natural fibre ropes, including cotton, jute, hemp, sisal and manila hemp. The most commonly used soft wire ropes are twisted pair ropes; for smaller diameters there is a 6x19M - FC rope and for larger diameters – 6x37M...
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The effectiveness of polymer adhesive in reduction of vibrations of structural members
PublicationIn this paper, the idea of using polymer adhesive as a damping layer is proposed. An experimental study of two aluminium cantilevered beams has been conducted. One of them presents a plain cantilevered beam, while the second one considers two aluminium beams bonded with a polymer adhesive of different thickness (0,5; 1,2; 1,75; 3,1 and 5 mm). The polymer adhesive considered in the study is a specially designed flexible...
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Innovative system for energy collection and management integrated within a photovoltaic module
PublicationThe dynamic development of battery technology and design based on the flow of lithium ions, mainly driven by the needs of the automotive industry, leads to the conclusion that these batteries are becoming a more viable alternative to traditional lead-acid batteries. Their use is driven by the ability to quickly charge and discharge, a higher durability, maintenance-free operation, much smaller dimensions and lighter weight. The...
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Simulation of fluid structure interaction in a novel design of high pressure axial piston hydraulic pump
PublicationA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
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Unsaturated, biobased polyesters and their cross-linking via radical copolymerization
PublicationBiobased, unsaturated polyesters derived from isosorbide, maleic anhydride and succinic acid were synthesized and characterized. The presence of maleic anhydride units in the structure of the polyesters allowed converting them into cured coatings by radical copolymerization with cross-linking agents such as 2-hydroxyethyl methacrylate, N-vinyl-2-pyrrolidinone, acrylic acid or methacrylamide. The investigated polyesters were obtained...
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Photovoltaic bulk heterojunctions with interpenetrating network based on semiconducting polymers
PublicationPhotovoltaic cells are supposed to be the most common generators of useful electricity in the nearest future as they utilize inexhaustible carriers of renewable energy called photons. Despite the fact that 95% of worldwide applied photovoltaic devices are based on inorganic semiconductors the area of organic photovoltaics grows successively due to possibility of considerable reduction of manufacturing costs. Since the Heeger's...
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Vitamin B9 as a new eco-friendly corrosion inhibitor for copper in 3.5% NaCl solution
PublicationFolic acid salt (sodium folate) was studied as an eco-friendly and non-toxic copper corrosion inhibitor in 3.5% NaCl solution. Electrochemical impedance spectroscopy, polarization resistance and weight-loss measurements show that the inhibitor efficiency increases with concentration (the highest value- approx. 96% was reported for the solution containing 16 mM sodium folate after 24 h). EIS data and Tafel plots indicate that sodium...
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Evaluation of structural change during fast transformation process of cross-linked NR into liquid NR by light pyrolysis
PublicationThe presence of cross-linked networks in rubber creates a tremendous problem for recycling and reusing of waste rubber. Fast transformation of cross-linked natural rubber (NR) into liquid natural rubber was carried out by light pyrolysis in temperature range from 240 to 300 °C in variable time (in range: 1–30 min). The transformation efficiency was evaluated by measuring the sol fraction and the cross-link density of the gel fraction....
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Simulation of fluid structure interaction in a novel design of high pressure axial piston pump
PublicationA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
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Synthesis and characterization of novel renewable polyesters based on 2,5-furandicarboxylic acid and 2,3-butanediol
PublicationNovel polyesters from 2,5-furandicarboxylic acid or 2,5-dimethyl-furandicarboxylate and 2,3-butanediol have been synthesized via bulk polycondensation catalyzed by titanium (IV) n-butoxide, tin (IV) ethylhexanoate, or zirconium (IV) butoxide. The polymers were analyzed by size exclusion chromatography, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy (FTIR), matrix-assisted laser ionization-desorption...
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INFLUENCE OF CERAMIC COATING ON MECHANICAL PROPERTIES OF STAINLESS STEEL
PublicationCrystal structure and phase composition of stainless steel substrates (AISI 304 type) was studied and it was found that they adopted the cubic symmetry. The calculated elementary cell parameter for the mayor Fe-Ni phase (weight fraction 99%) was a = 3.593 Å, whereas the mean grain size was = 2932 Å. Morphology of the stainless steel substrate surface was studied with profilometry. Mechanical properties of the stainless steel...
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Predicting Performance of Lightweight Concrete with Granulated Expanded Glass and Ash Aggregate by Means of Using Artificial Neural Networks
PublicationLightweight concrete (LWC) is a group of cement composites of the defined physical, mechanical, and chemical performance. The methods of designing the composition of LWC with the assumed density and compressive strength are used most commonly. The purpose of using LWC is the reduction of the structure’s weight, as well as the reduction of thermal conductivity index. The highest possible strength, durability and low thermal conductivity...
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New ceramic materials derived from pyrolyzed poly(1,2-dimethylsilazane) and starch as a potential anode for Li-ion batteries
PublicationNewmaterialswere obtained by pyrolysis of starch (S) and poly(1,2-dimethylsilazane) (PSN) (weight ratio: PSN/S 30/70) at temperature a) 500 °C, b) 700 °C and c) 900 °C. Ceramic materials were characterized by infrared spectroscopy, TGA, Raman spectroscopy and SEM. New Si\O and shifted Si\C stretching vibration modes emerged confirming direct interaction between silicon originating fromsilazane and oxygen coming fromstarch. The...
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Biopolyols obtained via microwave-assisted liquefaction of lignin: structure, rheological, physical and thermal properties
PublicationThe present study examined the application of polyols obtained via microwave-assisted liquefaction of lignin in the production of rigid polyurethane foam. Lignin was liquefed in crude glycerol and 1,4-butanediol at diferent temperatures (130–170 °C), without a catalyst and using various biomass concentrations (15 and 30 wt%). The physicochemical properties, process yield, and FTIR-based identifcation of the obtained polyols were...
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Bio‐polyols synthesized by liquefaction of cellulose: Influence of liquefaction solvent molecular weight
PublicationCurrently, the plastics industry including polyurethanes is based on the use of petrochemicals. For this reason, scientists are looking for new types of renewable resources for the substitution of petrochemical substances. This work aims to evaluate the effect of polyethylene glycols (PEG) with different molecular mass impact on properties of bio-based polyols synthesized via biomass liquefaction of cellulose. To date, research...
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Giant Reed (Arundo donax L.) Fiber Extraction and Characterization for Its Use in Polymer Composites
PublicationThis work describes an extraction method for giant reed fibers from stems and leaves based on chemical soaking and crushing through a rolling mill. Obtained fibers, together with the shredded plant (stems + leaves), are characterized in terms of chemical composition, thermal stability, morphology, and crystallinity. Mechanical properties of fibers have also been assessed (single fiber tensile tests). The results show that the proposed...
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Evaluation of Body Surface Area Formulae Based on 3D Body Scans
PublicationHuman body surface area (BSA) is an established parameter for the calculation of chemotherapy drugs dosage, treatment of chronic hepatitis B, treatment of burns or for establishing a dosing regimen for antimicrobials. Although being a critical parameter, usage of modern 3D scanners, which would measure the exact BSA value, is often impossible in time-sensitive operations or for patients unable to withstand the scanning process....
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Thermo-Chemical Decomposition Study of Polyurethane Elastomer Through Glycerolysis Route with Using Crude and Refined Glycerine as a Transesterification Agent
PublicationDue to the increasing amount of polyurethane waste, chemical recycling of these materials is a topic of growing interest for many researchers. The primary pur- pose of polyurethane feedstock recycling is to recover the starting polyol. In this study glycerolysis using glycerine from two sources and two purity grades is proposed as a method of chemical recycling. The main effort of this paper focuses on the employment of commercial...