Filters
total: 838
filtered: 612
Search results for: elephant grass
-
Effect of Glass Powder on the Cement Hydration, Microstructure and Mechanical Properties of Mortar
Publication -
Lightweight glass and metal roof structures in the 19th century. Architecture and construction.
PublicationThe 19th century brought new construction possibilities. The usage of metal elements in mesh structures, filled in with glass, resulted in creating entirely new types of objects. They have distinguished themselves in architecture and technical solutions. The envelope structures giving spatial interiors were arising very quickly. They have been enabling large light penetration, triggering them extremely bright. Thus these building...
-
The Issue of Shading Photovoltaic Installation Caused by Dust Accumulation on the Glass Surface
PublicationThe issue of accumulation of dust and other pollutants on the surface of photovoltaic modules was thoroughly analysed over the years. One of the first surveys in this field of knowledge linked pollutant accumulation on the module surface with transmittance loss of its glass covering, which leads to lessened amount of solar radiation reaching solar cells. First stage of this accumulation process is linear transparency loss, and second...
-
Niobate in silicate and phosphate glasses: Effect of glass basicity on crucible dissolution
PublicationUsing niobium crucibles for melting phosphate and silicate glasses of various modifier oxide contents, and therefore varying optical basicity (Λ), was found to result in varying dissolution rates of niobate during melting. Because of their high electronic polarizability, even small concentrations of niobates are detectable in the Raman spectra of glasses. Even less than 1 mol% Nb2O5 can be identified, as independently confirmed...
-
Degradation of Gel-Coat Layer in Glass/Polyester Laminate in Seawater Environment
PublicationGlass/polyester laminate coated with gelcoat layer of different thickness 0,5; 1,5; 3 mm was studied in terms of blistering behaviour and water sorption in hot water environment. Blistering was found to be accelerated for thin (0,5 mm) gel-coat layer compared to the thick (1,5; 3 mm), however no significant difference in blistering behaviour was observed between the laminates with gel-coat thickness 1,5 and 3 mm which may suggest...
-
Low velocity impact damage in glass/polyester composite sandwich panels
PublicationZbadano odporność udarową konstrukcji przekładkowych z laminatu poliestrowo szklanego pod kątem adhezji z rdzeniem (pianki PVC) przy polaczeniu dwoma rodzajami kleju lub łączanymi na ''mokro'' przy pomocy żywicy w trakcie utwardzania laminatu. Do oceny obszaru zniszczeń udarowych zastosowano metodę ultradźwiękową, która umożliwia wykrycie pola delaminacji nakładających się na siebie w poszczególnych warstwach .Obszary zniszczeń...
-
The structure and melting of lead nanocrystalline layer in reduced lead-germanate glass
PublicationNanokrystaliczna warstwa granul Pb na powierzchni szkieł ołowiowo-germanianowych została wytworzona poprzez wygrzewanie w wysokich temperaturach, w atmosferze wodoru. Właściwości tej warstwy silnie zależą od temperatury i czasu redukcji. Artykuł prezentuje rentgenowskie i mikroskopowe badania struktury warstwy oraz wpływ topnienia i krzepnięcia granul Pb na jej przewodnictwo.
-
Electronic conductivity in the SiO2-PbO-Fe2O3 glass containing magnetic nanostructures
PublicationThe linear impedance spectra of iron–silicate–lead glass samples were measured in the frequency range from 1 MHz to 1 MHz and in the temperature range from 153 K to 423 K. The structure was investigated by means of XRD and atomic force microscopy. Local electrical and magnetic properties of the samples were tested with the aid of electrostatic force microscopy (EFM) and magnetic force microscopy (MFM). The obtained results show...
-
Electrical properties and structure of lead-borate glass containing iron ions.
PublicationThe ac and dc conductivity in iron–lead-borate glass samples was investigated in the frequency range from 1 mHz to 1 MHz and in the temperature range from 153 K to 423 K. The structure was investigated by the means of atomic force microscopy (AFM) and the crystalline phases (if present) were identified by the means of X-ray diffractometry. Two types of ac electrical behaviour were observed. The first group of glass samples which...
-
Mechanical, thermo-mechanical properties of epoxy/glass composites with submicron particles
PublicationIn this research the influence of submicron zinc oxide and silicon dioxide particles on mechanical, thermo-mechanical properties of epoxy matrix composites reinforced with glass fibres was investigated. Composites were fabricated using hand lay-up method. Materials contained 39-41 wt.% of glass fibres. The bending tests, dynamic mechanical analysis and tribological tests were performed on each group of composites and also for...
-
Influence of concentration on contact angle of water-Cu nanofluid on glass substrate
PublicationIn the paper the results of an experimental investigation of influence of nanoparticle concentration on contact angle of water-Cu nanofluid on glass substrate have been presented. Nanoparticles were tested at the concentration of 0.01%, 0.1%, and 1% by weight. In the present study copper was applied as nanoparticle while distilled, deionized water was used as a base fluid. The mean diameter of nanoparticle is estimated to be 50...
-
Application of lightweight cement composite with foamed glass aggregate in shell structures
PublicationThe purpose of the paper is to investigate the abilities of applying Granulated Expanded Glass Aggregate (GEGA) as a natural volume substitute of aggregate as a component of lightweight concrete. The GEGA aggregates used in the experiments were made of confused glass waste. In order to achieve satisfactory strength of concrete Granulated Ash Aggregate (GAA) was added as well. To produce specimens three grain sizes of aggregates...
-
High Rise Building: The Mega Sculpture Made Of Steel, Concrete and Glass
PublicationHigh rise building has transformed from providing not only the expansion of floor space but functioning as mega sculpture in the city. The shift away from economic efficiency driven need is only expected to grow in the future. Based on literature studies; after analysing planning documents and case studies, it was examined whether the presumption that gaining the maximum amount of usable area is the only driving factor; or if the...
-
Spin-glass behavior in a binary Pr 3 Ir intermetallic compound
PublicationPolycrystalline Pr3Ir was synthesized by arc melting. Its cementite-type crystal structure (Pnma) was confirmed by powder X-ray diffraction and estimated lattice parameters are in agreement with literature. Physical properties were measured by means of the ac and dc magnetic susceptibility, electrical resistivity and heat capacity. Our results indicate spin-glass behavior in Pr3Ir with a freezing temperature Tf = 6.58 K and activation...
-
CEE Trade in Services: Value-Added Versus Gross Terms Approaches
PublicationThis article assesses the impact of the determinants of service exports in both value-added terms and gross terms for seven Central Eastern European economies in 1995–2011. The results confirm the importance of increasing labor productivity and highly skilled and medium-skilled workers in the growth of trade in services. Exports of services are also supported by linkages between domestic services, especially business services,...
-
The structure of Pb-PbO-SiO2 glass via molecular dynamics simulation
PublicationPraca poświęcona jest badaniom struktury blisko i średniozasięgowej częściowo zredukowanego szkła ołowiowo-krzemianowego o stechiometrii 1Pb1PbO1SiO2 uzyskanego na drodze symulacji dynamiczno-molekularnych. Otrzymane rezultaty porównamy z danymi otrzymanymi dla szkła niemodyfikowanego (2PbO1SiO2) i całkowicie zredukowanego (2Pb1SiO2).
-
Chemically modified glass fiber as a matrix-free reference material for volatile compounds
PublicationW pracy opisano sposób wytwarzania nowego typu bezmatrycowych materiałów odniesienia lotnych związków organicznych. Do otrzymywania lotnych analitów wykorzystano technikę termicznego rozkładu związków powierzchniowych. Jako nośnik zastosowano modyfikowane chemicznie włókna szklane. Związkiem oznaczanym był chlorek metylu.
-
On delamination threshold loads in low velocity impact on glass-carbon/epoxy composites.
PublicationZbadano możliwości zastąpienia badań udarowych o niskiej energii ze spadającą masą badaniami quasi-statycznymi przy analogicznym obciążeniu próbki dla laminatów epoksydowych wzmocnionych włóknami węglowymi i szklanymi oraz węglowymi. Uzyskano dobrą zgodność wyników obu typów badań , co znajduje potwierdzenie w wynikach innych badaczy.
-
Correlations of structural, thermal and electrical properties of sodium doped complex borophosphosilicate glass
PublicationBorophosphosilicate glasses with varying sodium ion concentrations were investigated for their, structural, thermal, and electrical properties. All the obtained glasses were transparent except the glass with the highest sodium content, which exhibited translucency due to inhomogeneities. Increasing sodium content led to reduced boron and silicon content while maintaining a constant B/Si ratio, indicating progressive depolymerization...
-
Enhancing electrical properties through in-situ controlled nanocrystallization of V2O5–TeO2 glass
PublicationV2O5–TeO2 glass–ceramics (VTGC) were prepared by controlled annealing of the V2O5–TeO2 glass (VTG), which illustrates a parent glass matrix with a single charge carrier. The annealing proceeded at six temperatures selected between the glass transition and the maximum of the frst crystallization process to obtain various nanocrystallite sizes. Heat treatment caused an increase in DC conductivity by 2.5–3.5 (250–285 °C) order of...
-
Nonlinearity shaping in nanostructured glass-diamond hybrid materials for optical fiber preforms
PublicationNanodiamond integration with optical fibers has proved a compelling methodology for magneto-optics. We reveal that the applicability of nanodiamonds in nonlinear optics goes beyond the previous demonstrations of frequency converters. Instead, we exploit the recently reported volumetric integration of nanodiamonds along the optical fiber core and show that the nonlinear response of glasses can be manipulated by nanodiamonds. By...
-
Increasing the conductivity of V2O5-TeO2 glass by crystallization: structure and charge transfer studies
PublicationIn the present paper, V 2 O 5 -TeO 2 glass was prepared by the melt-quenching technique. Crystallization of glass with a vanadium content higher than 35%mol results in an increase in electrical conductivity by a few orders of magnitude and a decrease in activation energy from ~0.40 to ~0.12 eV. In this work, a critical review of existing charge transfer models was presented on the example of V 2 O 5 -TeO 2 glass and glass–ceramics....
-
Autonomous Perception and Grasp Generation Based on Multiple 3D Sensors and Deep Learning
PublicationGrasping objects and manipulating them is the main way the robot interacts with its environment. However, for robots to operate in a dynamic environment, a system for determining the gripping position for objects in the scene is also required. For this purpose, neural networks segmenting the point cloud are usually applied. However, training such networks is very complex and their results are unsatisfactory. Therefore, we propose...
-
Structure and magnetic properties of BeO-Fe2O3-Al2O3-TeO2 glass-ceramic composites
PublicationIn this work, glass-ceramics in the xBeO–20Fe2O3–(80-x)TeO2 system with x = 0–25 mol% were synthesized by the traditional melt quenching route and studied by inductively coupled plasma optical emission spectroscopy, X-ray diffraction, confocal microscopy, infrared and Raman spectroscopy. BeO addition was found to support the crystallization process of Fe2O3 during melting, and an increased BeO content was associated with an increased...
-
Correlations of structural, thermal and electrical properties of sodium doped complex borophosphosilicate glass
Publication -
Enhancing electrical properties through in-situ controlled nanocrystallization of V2O5–TeO2 glass
Publication -
Electronic conduction in (Bi,Pb)–Sr–Ca–Cu–O glass-ceramics
Publication -
The effect of random surface topography height on fretting in dry gross slip conditions
Publication -
Increasing the conductivity of V2O5 -TeO2 glass by crystallization: structure and charge transfer studies
PublicationIn the present paper, V2O5-TeO2 glass...
-
Engineering Au nanoparticle arrays on SiO2 glass by pulsed UV laser irradiation
PublicationWe study semi-regular arrays of Au nanoparticles (NP) obtained via UV laser irradiation of thin Au films on glass substrate. The NP structures are prepared from films of a thickness up to 60 nm produced by discharge sputtering or pulsed laser deposition, and annealed by nanosecond laser pulses at 266 or 308 nm, respectively, at fluencies in the range of 60-410 mJ/cm2. For the rare- and close-packed NP structures, consistent description...
-
Influence of the rare-earth impurities on the Ga and Ge local structure in the Ca3Ga2Ge3O12 glass
PublicationW pracy przedstawione zostały wyniki analizy EXAFS realizowanejza pomocą metody GNXAS dla serii szkieł typu Ca3Ga2Ge3O12 domieszkowanych metalami ziem rzadkich (0.7 wt.% - Ce, Eu, Ho, Er; oraz 1.0 wt.% Nd). Badaniu poddano lokalne otoczenie wokół jonów Ge i Ga. Porównanie wyników z danymi strukturalnymi otrzymanymi dla szkła niedomieszkowanego wskazuje, że domieszka metali ziem rzadkich modyfikuje jedynie otoczenie jonów galu,...
-
Superconducting lead granular layer prepared by reducting in hydrogen lead of germanate glass
PublicationCienka warstwa granul Pb została wytworzona poprzez wygrzewanie w wodorze, w wysokiej temperaturze. Struktura i nadprzewodzące właściwości warstwy ołowiu zależą od temperatury i czasu redukcji. Artykuł analizuje wpływ warunków redukcji na wytworzoną warstwę granul Pb.
-
Novel method for metal-oxide glass composite fabrication for use in thermoelectric devices
PublicationA novel method for thermoelectric materials fabrication using a reduction of oxide precursors in hydrogen was reported. On the example of Bi-Sb, Bi-Sb-Te and Te-Ag-Ge-Sb compounds it was shown that this simple and easy method is suitable for fabrication of two-, three- and even multicomponent thermoelectric materials. It allows controlling a composition, microstructure and even type a of electrical charge carriers. As a result...
-
Investigation of polyurethane elastomer–steel joints using glass lacquer as an adhesive agent
PublicationThis article describes an innovative method of coupling polyurethane elastomer (based on polyurethane glycolysate) with constructional steel, by implementation of a Glaspur®—glass lacquer containing latent polyurethanes and monosilane adhesion promoters. The commonly applied coupling agent is Cilbond® 45SF glue or its derivatives. Additionally, glycolysate was synthesised from polyurethane waste and 1,3-propylene glycol in 6:1...
-
Nonlinear electrical properties of glass-ceramics nanocomposites containing ferroelectric nanocrystallites of Bi2VO5.5
PublicationNonlinear A.C. impedance measurements were conducted in the 50BiV-50SrBAlO nanocomposite as a function of frequency, temperature and A.C. voltage. This material is ferroelectric below temperature of 730 K, and above 730 K is a good ion-conductor. For this nanocomposite a low A.C. voltage of 1 V rms is enough to observe high nonlinearities. The origin of these nonlinear effects depends on the temperature and frequency. In the high...
-
Effect of porosity on physical properties of lightweight cement composite with foamed glass aggregate
PublicationThis paper reports on a study of physical properties of lightweight cement composite. We investigate the possibility of replacing traditional aggregate with Granulated Ash Aggregate (GAA) and above all with Granulated Expanded Glass Aggregate (GEGA). For this purpose, 15 specimens of different percentage share of each aggregate in total aggregate volume were tested: 0%, 25%, 50%, 75% or 100% of foam glass aggregate (GEGA) partially...
-
An EXAFS study of the local structure of rare-earth luminescence centres in the Ca3Ga2Ge3O12 glass
PublicationW pracy przedstawiono wyniki analizy EXAFS danych mierzonych na krawędzi L3 atomów ziem rzadkich takich jak Eu, Ho (0.7 wt.%) oraz Er (1.46 wt.%), którymi domieszkowano szkło 3CaO-Ga2O3-3GeO2. Otrzymane parametry strukturalne opisujące pierwszą powłokę koordynacyjną badanych atomów wskazują, że ich lokalne otoczenie tlenkowe jest jednakowe (niezależne od typu jonu ziemi rzadkiej) i uwzględniając strukturalny nieporządek bardzo...
-
Electronic conduction in (Bi,Pb)-Sr-Ca-Cu-O glass-ceramics
PublicationAmorficzny materiał (Bi,Pb)4Sr3Ca3Cu4Ox wygrzewany w odpowiednich warunkach staje się nieuporządkowanym metalem i nadprzewodnikiem. Przedstawiono model mechanizmu przewodnictwa elektrycznego tych materiałów. Przeprowadzono dyskusję istniejących teorii do opisu badanych materiałów.
-
Experimental and Numerical Study on Mechanical Characteristics of Aluminum/Glass Fiber Composite Laminates
PublicationThe fiber-metal composites made of aluminum sheets and glass fibers reinforced with a polyester resin as the matrix were studied. The composites were prepared by hand lay-up method. Some aspects of manufacturing affecting the composite behavior were considered. In particular, the influences of the arrangement of layers and their number on the mechanical and physical properties of composites with ten different compositions were...
-
Post-impact moisture absorption in hybrid glass, aramid, carbon/epoxy composites
PublicationZbadano chłonność wody i własności po udarze i absorpcji wody w laminatach hybrydowych aramidowo-szklano-węglowych. Badania porównawcze dla laminatów szklano-epoksydowych wykazały 18% i 33% spadek wytrzymałości na ściskanie odpowiednio w wyniku udaru o energii 10J oraz udaru i absorpcji wody.
-
Structural and electrical transport studies of reduced in hydrogen surfaceof bismuth germanate glass
PublicationOtrzymano nanostruktury krystalicznego bizmutu w matrycy szkła germanowegooraz warstwę nanostruktur krystalicznego bizmutu na powierzchni redukowanegow atmosferze wodoru szkła Bi0.33Ge0.67O1.83. Zaproponowano prosty model bu-dowy zredukowanych szkieł bizmutowo-germanowych potwierdzony wynikami badańAFM i XRD. Zbadano wpływ czasu i temperatury redukcji oraz topnienia bizmu-tu na własności elektryczne badanych szkieł. Przeanalizowano...
-
Gel glass transition in silica and nitrided silica aerogels experiment and computer modelling.
PublicationPrzedstawiono dane eksperymentalne i symulacje komputerowe metodą dynamiki molekularnej procesu densyfikacji do szkła aerożeli krzemianowych i azotowanych aerożeli krzemianowych.
-
Polyvalent Mechanical Bacterial Lysate Administration Improves the Clinical Course of Grass Pollen–Induced Allergic Rhinitis in Children: A Randomized Controlled Trial
Publication -
Evaluation of corrosion inhibition of brass-118 in artificial seawater by benzotriazole using Dynamic EIS
Publication -
Graffiti saves birds: A year-round pattern of bird collisions with glass bus shelters
Publication -
Computer study of the lead-germanium alloy formation in over-reduced lead-germanate glass
PublicationPraca poświęcona jest badaniom dynamiczno-molekularnym struktury zredukowanego szkła ołowiowo-germanianowego o składzie 1Pb 1Ge 1GeO2. Analizie poddano strukturę matrycy szkła, GeO2 i osadzonej w niej fazy metalicznej, którą formują neutralne atomy Pb i Ge.
-
Effect of slag coal ash and foamed glass on the mechanical properties of two-stage concrete
PublicationTwo-stage concrete (TSC) is known by various names such as colcrete, Polcrete, preplaced aggregate concrete and prepacked concrete. It is different from traditional concrete in two fundamental ways, namely method of construction and mix proportion. Two-stage concrete (TSC) is defined as firstly, coarse aggregates are placed into the formwork and grout is applied to fill in the between coarse aggregate particles voids. Secondly,...
-
Mechanism of hopping conduction in Be–Fe–Al–Te–O semiconducting glasses and glass–ceramics
PublicationElectrical properties of beryllium-alumino-tellurite glasses and glass–ceramics doped with iron ions were studied using impedance spectroscopy. The conductivity was measured over a wide frequency range from 10 mHz to 1 MHz and the temperature range from 213 to 473 K. The D.C. conductivity values showed a correlation with the Fe-ion concentration and ratio of iron ions on different valence states in the samples. On the basis of...
-
Modelling of laminated glass PVB walls of buildings exposed to vehicle impact with different speeds
PublicationThis paper presents an analytical model, developed for laminated glass subjected to a low-velocity impact. It has the ability to capture glass cracks as well as large non-linear deformations. It is based mathematically on the firstorder deformation concept, which considers the effect of membrane and transverse shear as well as bending. This theory uses damage mechanics to capture the glass cracking. For this purpose, several experiments...
-
Characterization of Mechanical and Bactericidal Properties of Cement Mortars Containing Waste Glass Aggregate and Nanomaterials
Publication