bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Mechanical Properties of Ceramic Composites by Harmonic Microstructure Control
Authors: Anggraini Lydia , Yamamoto Ryohei , Hagi Kazuma , Hiroshi Fujiwara , Ameyama Kei
Published: February 2014

In this research, several ceramic composites such as SiC-ZrO2, Al2O3-ZrO2, and Si3N4-ZrO2 containing nominally equal ratio 1:1 were prepared through high energy mechanical milling and spark plasma sintering. The relationship of microstructure and mechanical properties were investigated. Harmonic microstructures consisting of fine and ultra-fine grains forming a network were obtained by the optimum milling time for 144ks with high mechanical properties. The non-milled powder mixtures and too long milling time powder mixtures have low mechanical properties sintered by spark plasma. The crack propagates through ultra-fine grains and deflected by larger fine grains were obtained on the harmonic microstructure sample resulting in high toughness. Thus, the harmonic microstructure can be considered a remarkable design tool for improving the mechanical properties of SiC-ZrO2, Al2O3-ZrO2, and Si3N4-ZrO2 as well as other ceramic composites.
Application of Carbon Fiber-Based Composite for Electric Vehicle
Authors: Anwar Miftahul , Cahyono Sukmaji Indro , Wijang Wisnu R. , Diharjo Kuncoro
Published: February 2014

In the present work, we study how to improve mechanical properties of carbon fiber reinforced plastics (CFRP) in order to increase crashworthiness probability. Experimentally, hybrid carbon /glass fiber composite was made in order to get higher mechanical properties. As a results, with increasing carbon fiber volume fraction (% vol.), tensile strength and flexural strength of the composite are increased. Simulation of impact testing is also performed using data properties taken from the experiment with variation of impact forces on front bumper structure. By varying external load to the bumper, the result shows that higher thickness of hybrid carbon/glass fiber composite has always smaller stress values than thinner one. On the other hand, the displacement of hybrid carbon/glass car bumper increases linearly with increasing external load.
In Situ Al/Al2O3 Composite Coating on Steel Substrate Prepared by Mechanical Alloying at High Temperature
Authors: Wismogroho Agus Sukarto , Widayatno Wahyu Bambang
Published: February 2014

In this study a new technique for producing an Al/Al2O3 composite coating on a steel substrate by an in situ process was examined. The pre-treating of the steel substrate with Al was carried out by MA at room temperature, followed by MA using a low-energy ball mill at 200-500°C. An Al/Al2O3 coating layer with a homogenous distribution of Al2O3 particles were achieved. The coating layer has not only high hardness but also high fracture toughness.
Nano-Micro Characterization of NiCoCrAl Coating on Carbon Steel Substrate
Authors: Eni Sugiarti , Zaini Kemas , Wang Yong Ming , Hashimoto N. , Hayashi Shigenari , Ohnuki Somei
Published: February 2014

The corrosion of carbon steel is major infrastructure degradation problem in practically all industries, including chemical materials, mineral, and petrochemical industries. Coating on carbon steel is one of the techniques which required improving corrosion resistance in extreme environments. In present work, NiCoCrAl was diffusion-coated onto low carbon steel by electrodeposition for NiCo and pack cementation for Cr and Al. The cross section of coated specimen was observed and analyzed using SEM and TEM. Two types of coating processes have been challenging the formation of bond-coat layer on carbon steel substrate with different temperature coating process. SEM and EDS results show that the coating comprises three layers: intermetallics zone of Ni (Al) and Al (Cr), interdiffusion zone of Ni (Co), and there is the substrate. By XTEM observation, it was found that γ (Ni,Fe) and ζ hexagonal structure were identified in all specimens. Orthorhombic structure with the Al3Ni was identified in specimen developed at temperature of 800OC. Further, the top surface of a 1000OC specimen has two phases of β-NiAl and ζ hexagonal structure. In order to understand the performance of two types coating system with different temperature process, oxidation test at temperature of 800OC for 100 hours has been carried out and the result shows that coating system which was developed at 800OC has better oxidation resistance compare to 1000OC coating system.
Interdiffusion of Elements in Aluminum 2024 Clad during Reheat Treatment Process at 495°C
Authors: Basuki Eddy , Sutarno Sutarno , Samuel Samuel
Published: February 2014

Aluminum alloy 2024 is normally strengthened with alloying elements of Cu and Mg. As these elements reduce the corrosion resistance of the materials, a pure Al clad is normally applied. Nevertheless, during ageing at high temperatures, inter-diffusion between elements can occur and causing the recession of the clad. This study investigates the inter-diffusion behavior Al 2024 clad at ageing temperature of 495°C and predicts the clad lifetime due to reheat treatment process. The depletion rate of clad was found at 0.8 μm per-hour of heat treatment. It is predicted that the thickness of the Al 2024 clad will no longer meet with the specifications on heat treatment for 42 hours at 495°C.
Effect of Copper Addition on the High Temperature Oxidation of Zirconium Alloy ZrNbMoGe for Advanced Reactor Fuel Cladding Material
Authors: Bandriyana Bernardus , Prajitno Djoko Hadi , Dimyati Arbi
Published: February 2014

The zirconium alloys ZrNbMoGe have been developed with the aim to improve its high temperature oxidation for employment as a cladding material in Pressurized Water Reactor (PWR) and to extend the over all fuel burn-up. In this paper the effect of Cu addition on the high temperature oxidation behavior of ZrNbMoGe alloy was investigated. The zirconium alloy was produced by melting the zirconium-niobium-molybdenum-germanium and copper-sponge in an arc furnace in an argon environment by the temperature higher than 1850C. The weight percentages of the elements were 2.50 wt.% Nb, 0.5 wt.% Mo, 0.1 wt.% Ge, 0.5 wt.% Cu and Zr in balanced. The oxidation test was carried out in the Magnetic Suspension Balance (MSB) workstation. Two specimens of ZrNbMoGe alloys without and with Cu addition were oxidized in atmosphere at temperature of 500 °C and 700 °C for 8 hours. The results show the oxidation kinetics followed the parabolic rate law. The difference of oxidation behaviors of the two specimens were considered to be caused by the formation of different kind of oxide layers due to the Cu addition.
Fractographic Analysis of 5052 Al-Mg Alloys Processed by Equal Channel Angular Pressing
Authors: Mabruri Efendi , Gede I. Nyoman Putrayasa A.
Published: February 2014

In this work, ECAP technique has been applied to 5052 Al-Mg alloys where the alloys find wide application in building and construction, automotive, cryogenic and marine applications. The alloy samples extruded by ECAP with four different deformation routes for 4 passes each were tensile tested and the observation of the fracture surfaces were carried out by using digital camera and Scanning Electron Microscope (SEM). The experimental results showed that the initial pre-annealed sample showed cup and cone shape of fracture, whereas the fractured ECAPed samples of all deformation routes exhibited shear feature in which the fracture surface made an angle with pressing direction of ECAP. The change of size and shape of dimples fracture from larger and irregular shape dimples in initial sample to much smaller and grains-look like dimples in ECAPed sample indicating the grain refinement occurred after ECAP. Among the ECAP deformation routes applied, route BC resulted in smallest dimples size, i.e. about below 2 mm in average. The post annealing subjected to ECAP samples recovered almost completely the fracture feature and fracture morphology to that of the initial one, which was achieved after annealing at 300°C.
Fatigue and Mechanical Properties of Aluminium-Copper Bi-Metal Tubes
Authors: Sajuri Zainuddin , Baghdadi Amirhossein , Mahmod Muhammad Faisal , Syarif Junaidi
Published: February 2014

Metallurgical bonded aluminium-copper bi-metal tube has a future prospect as an alternative material to copper in the heat, ventilation and air-conditioning (HVAC) industries. The application of aluminum-copper bi-metallic material is seems practical in maintaining the quality of existing products. However, the mechanical strength and fatigue properties of the bi-metal tubes are unknown. In this study, metallurgical, mechanical and fatigue properties of the copper phosphorous alloy and aluminium-copper bi-metal tubes were characterized through metallographic analysis, tensile, bending and fatigue tests. The results show that there observed a weak and brittle Al-Cu intermetallic compound at the interlayer between Al and Cu. Tensile fracture surface observation revealed that separation of Cu from Al occurred at the interlayer. The bending properties of the tubes were influenced by the amount of volume fraction of Cu in the materials. Three point bending fatigue test results showed that a critical buckling stress is presents for tubes with diameter less than 12.7mm. The aluminium-copper bi-metal tubes show degradation of fatigue strength almost 55% as compared to that of Cu alloy tube.
Macrotexture Study of Non- and Sintered Pure Nb and Nb3Sn Using Orientation Distribution Function
Authors: Aniswatin Kholifatul , Risanti Doty Dewi , Pramono Andika Widya
Published: February 2014

This research uses pellets of non- and sintered pure Nb and the superconducting intermetallic compound of Nb3Sn. Sintering was undertaken at 700 °C for 96 hours. The texture data were obtained by using XRD Brüker D8 Advance equipped with gonio-texture and interpreted into namely inverse pole figures, pole figures, and orientation distribution function (ODF). In general, the pole figure analysis indicates that sintering process can lead to a change in the crystal orientation distribution from symmetric or random orientation into preferred orientation. Uni-axial compacting pressure in samples prior to sintering favors the appearance of a preferred orientation on a specific direction. However, this texture is not only retained upon subsequent sintering, but can become much more pronounced or weaker due to the crystal growth occurring at elevated temperatures. The main feature of initial texture for pure compacted Nb obtained in this study is Brass, S, and Copper with Brass being the maximum, whereas Cube and Goss appear as minor components. Upon sintering, it has been found that S, Brass, and Copper retained as the dominant ones, with S has been developed and being the maximum. On the contrary, a significant change in texture upon sintering has been obtained for Nb3Sn, namely Copper, S and Brass components with minor Cube and Goss components for initial condition, and Copper, Goss and Brass with minor Cube and S components for sintered sample. It is noted that the Copper intensity of Nb3Sn decreases from 50.4 to 39.3 multiple of random distribution (m.r.d) for the initial and upon sintering conditions, respectively.
Modeling of Repeated Rolling Contact on Rough Surface: Surface Topographical Change
Authors: Ismail Rifky , Saputra Eko , Tauviqirrahman Mohammad , Jamari J. , Schipper Dirk Jan
Published: February 2014

An finite element analysis (FEA) of a repeated rolling contact over an elastic-plastic deforming rough surface is performed. The surface topographical change is calculated to determine the running-in phase to the steady-state rolling contact situation. A rigid hemisphere is repeatedly rolled over a rough flat aluminum surface and the effect of the contact load and the number of overrollings is studied. It is found that the change in surface topography due to the repeated rolling contact results in smoothening of the rough surface due to the flattening of the highest asperities. The result shows that the running-in of the repeated rolling contact takes place within the first few overrollings.
Neutron Diffraction Measurements on Dissimilar Metal Weld of Cu-Al Obtained by Friction Stir Welding Method
Authors: Priyanto Tri Hardi , Bharoto Bharoto , Muslih Rifai , Mugirahardjo Herry
Published: February 2014

Dissimilar metal weld (DMW) of Cu and Al alloy, namely DMW CuAl, was produced using Friction Stir Welding (FSW) technique. Characterization was performed at retreating and advancing side by neutron diffraction method. It is obtained that the weight percent composition of Cu and Al are dynamically change, depend on weld zone and welding direction. In SZ Cu element 55,18%, and it is majority component in the retreating side and it decreases gradually from the retreating side to the advancing side. The weight percent composition of Cu in the retreating side at HAZ and TMAZ are 99.25 %, and 61.25%, respectively, and in the advancing side are 0.35% and 38.75 %, respectively. Cu Bragg peaks of (111), (200) and (220) show that peak width ratio of BMZ / SZ is approximately 13%. This indicates a change in crystallite size that affects the behavior of plastic deformation in the welded material.
Testing of Materials for Heat and Moisture Transport
Authors: Dvořák Václav , Novotny Petr , Vít Tomáš
Published: February 2014

The article deals with testing materials for using in enthalpy exchangers. The purpose of the enthalpy heat exchangers is to transport the heat and moisture together. Such heat exchangers are used in heat and ventilation air conditioning units. There are several methods how to test transport of moisture through material used in textile industry. However, these methods are not suitable for testing of materials, which are considered to be in heat exchangers. Methods for testing of moisture transport are usually based on free convection around membrane, which separates spaces with air of low humidity and air saturated with water. The free convection does not occur in heat exchangers and moisture varies in wide range. Therefore we developed and tested a devise to simulate moisture transport in enthalpy heat exchangers with plates, where co-current and countercurrent occur. With the help of this device, we could compare materials and evaluate the influence of the surface structure, which affect the boundary layers and heat and mass transport, when the flow is tangential to the material surface. We could also investigate the effect of flow velocity and humidity. The methods of evaluation are discussed and some results are presented.
Eggs Shell Membrane as Natural Separator for Supercapacitor Applications
Authors: Taer Erman , Sugianto Sugianto , Sumantre M.A. , Taslim Rika , Iwantono Iwantono , Dahlan D. , Deraman M.
Published: February 2014

Various eggs shell membranes (ESMs) have been used as a separator for supercapacitor application. The separator was prepared from different membranes such as chicken eggs shell membrane (CESM), duck eggs shell membrane (DESM) and goose eggs shell membrane (GESM). The ESMs were tested as a separator in a two-electrode system, the sandwich-type supercapacitor cell consists of two activated carbon monoliths as electrodes, two stainless steel as current collectors and 1 M H2SO4 solution as an electrolyte. The electrochemical performance of the ESMs was characterized by an electrochemical impedance spectroscopy, a cyclic voltammetry and a galvanostatic charge-discharge. The results of this study exhibit all of the ESMs as a good candidate for supercapacitor separator. However, the CESM was shown excellence electrochemical properties, such as low resistance, high energy density and power density. The scanning electron microscope (SEM) micrograph and X-ray diffraction analysis were also proved that the ESMs are a promising low-cost separator for supercapacitor application.
Automation of Four Circle Diffractomete /Texture Diffractometer for Studies of Crystal Structure and Texture Measurements
Authors: Bharoto Bharoto , Ramadhani Achmad , Suparno Nadi , Priyanto Tri Hardi
Published: February 2014

National Nuclear Energy Agency of Indonesia has several neutron beam instruments for materials science research. One of the instrument is Four Circle Diffractometer / Texture Diffractometer for study of crystal structure and texture measurement. Due to the instrument is fully occupied by many samples, the instruments has to be further developed in order to conduct experiment effectively and efficiently. For that reason, the instrument controller has been replaced with a new programmable controller that can handle all axis simultaneously. Since the controller has been replaced with the new one, a software for data acquisition and measurement also has been modified using a visual basic of programming language with an addition of function, i.e. an automatic measurement for either single-crystal or poly-crystal sample. The software calculates four peaks of Miller indices of the sample for determining the crystal position to be scanned. Then, the software performs the automatic measurement started from scanning the axis of θ-2θ, calculating the peak position by fitting the data obtained from sample diffraction data, then positioning the θ and 2θ axis to the peak position. Finally, the software performs the scanning of the π-χ axis for texture analysis, and save the experiment data into a certain format for the texture analysis software, i.e. Material Analysis Using Diffraction (MAUD).
Celluloide Film Based Infrared Bandpass Filter for Thermography
Authors: Kusminarto Kusminarto , Pratiwi Umi
Published: February 2014

A commercial digital camera was employed for thermal imaging. To do so, an infrared filter was required to block the light except the infrared part of it. The filter was developed using a celluloide colour film burned by certaint intensity of light. In this reseach intensity of monochromatics as well as polychromatics light of 1.00, 1.50, 2.70, 4.00, 8.00, 12.00, 16.00, 24.00, 30.0 and 40.00 klux have been used. The infrared filter produced then characterised their light transmitance using a spectrophotometer. Images of a light bulb and a hot iron plate were taken in a dark room using a digital camera equiped with and without infrared filter. The results show that the infrared filter produced from a celluloide colour film burned by a monochromatics light at intensity of 1.00 klux has the best permomance.
Effect of EDTA and PYP as Co-Ligand of Radiolabeled Nanomaterial M41S-NH2 for Radiosynovectomy
Authors: Daruwati Isti , Christina Maria P. , Perdana Wahyu W. , Hakiki Nugrahaning Wuri , Oekar Nanny Kartini
Published: February 2014

Radiosynovectomy is an innovative medical treatment for rheumatoid arthritis joints. A small amount of beta-emitting radiopharmaceutical is injected into the joint with intra-articullar route of administration. An ideal radionuclide for this treatment is beta emitter whose minimal gamma ray emission, tissue penetration between 5 10 mm, has short half life, high chemical purity and non-toxic properties such as Rhenium-188. For delivering the radionuclide to the specific target site in the synovial tissue and preventing the leakage to the lymph, an ideal carrier as particulate or colloidal compounds is requaired. A silica-based nanomaterial called M41S-NH2 was developed as therapeutic carriers by Polytechnic Institute of Nuclear Technology, Yogyakarta. The advantage of M41S-NH2 is biocompatible and not toxic to human body. As a preliminary experiment, M41S-NH2 was labeled using Technetium-99m which has a similar chemical properties with Rhenium-188. The radiolabelling performed in this system is the indirect method. The purpose of this research is to obtain the highest radiochemical purity of radiolabeled 99mTc-M41S-NH2 by using two co-ligands such as ethylenediaminetetraasetic acid (EDTA) and sodium pyophosphate (PYP). Some parameter such as pH, ratio of SnCl2 to co-ligand, ammount of reductor agent, ammount of M41S-NH2 were optimized in those experiments. Radiochemical purity determination was conducted by ascending paper chromatography method using Whatman 31-ET as stationary phase and physiological saline (NaCl 0,9%) as mobile phase. The optimum condition obtained from the investigation were by using 10 μg PYP as co-ligand, 10 μg SnCl2 as reductor agent, pH 9, and 10 minutes in room temperature as incubation time. More over the highest radiochemical purity obtained from those labeling experiments is 93.42± 0.06 %.
Weld Defect Classification in Radiographic Film Using Statistical Texture and Support Vector Machine
Authors: Muhtadan Muhtadan , Hidayat Risanuri , Widyawan Widyawan , Amhar Fahmi
Published: February 2014

Weld defect identification requires radiographic operator experience, so the interpretation of weld defect type could potentially bring subjectivity and human error factor. This paper proposes Statistical Texture and Support Vector Machine method for weld defect type classification in radiographic film. Digital image processing technique applied in this paper implements noise reduction using median filter, contrast stretching, and image sharpening using Laplacian filter. Statistical method feature extraction based on image histogram was proposed for describing weld defects texture characteristic of a radiographic film digital image. Multiclass Support Vector Machine (SVM) algorithm was used to perform classification of weld defects type. The result of classification testing shows that the proposed method can classify 83.3% correctly from 60 testing data of weld defects radiographic films.
Investigation of Moisture in Coal Using Electrical Capacitance Volume Tomography
Authors: Maulana Iriwn , Haryono Didied , Taruno Warsito P. , Al Huda Mahfudz , Baidillah Marlin , Sulaiman Rommy I.
Published: February 2014

A preliminary study about the development of Electrical Capacitance Volume Tomography (ECVT) for determining moisture, calorie and the flow of coal mass real-time on the conveyor has been done. This study aims to examine the capability and sensitivity of ECVT as a capacitance measurement system to investigate the correlation between moisture in coal and its dielectric property. The ECVT system comprises of a 2-channel rectangular sensor, data acquisition system and a computer system to control the measurement, process data and display the data of normalized capacitance of coal as the result. The linear correlation between moisture in coal and data of coal relative capacitance is obtained and presented in this paper. The results have shown that ECVT has good capability and sensitivity as a system to monitor the dielectric property and behavior of coal which are affected by the moisture content
Utilization of Fly Ash as Ceramic Support Mixture for the Synthesis of Zeolite Pervaporation Membrane
Authors: Alfiyan Bhagus , Susanto Heru
Published: February 2014

s. Ethanol purification is a key problem during fuel grade bioethanol production. Conventional distillation cannot be used any more after the ethanol concentration has reached azeotrophic condition (~95 wt.%). In this case pervaporation (PV) is recognized as one of the promising alternative purification technologies. The performance of pervaporation is significantly influenced by the membrane material used. This paper utilizes fly ash, a solid waste from coal combustion of thermal power plant, to prepare porous support pervaporation membranes. The support was prepared from a mixture of fly ash, kaolin and alumina. The support membrane was then coated by crytallization of hydrophilic zeolite. The results show that the the performance of support material was influenced by the preparation temperature and fly ash content. The addition of fly ash and the increase in alumina concentration would raise the mechanical strength of the membrane but the more the fly ash used the harder the support to be molded. An optimum fly ash content in support layer was found to be ~50 wt.% of the mixture. The higher calcination temperature the better the resulting support layer. Zeolite crystallization on the support layer was influenced by crytallization temperature, zeolite solution concentration, and crystallization time.
Excited-State Proton Transfer in Fluorescent Photoactive Yellow Protein Containing 7-Hydroxycoumarin
Authors: Novitasari Dian , Kamikubo Hironari , Yamazaki Yoichi , Yamaguchi Mariko , Kataoka Mikio
Published: February 2014

Green fluorescent protein (GFP) has been used as an effective tool in various biological fields. The large Stokes shift resulting from an excited-state proton transfer (ESPT) is the basis for the application of GFP in such techniques as ratiometric GFP biosensors. The chromophore of GFP is known to be involved in a hydrogen-bonding network. Previous X-ray crystallographic and FTIR studies suggest that a proton wire along the hydrogen-bonding network plays a role in the ESPT. In order to examine the relationship between the ESPT and hydrogen-bonding network within proteins, we prepared an artificial fluorescent protein using a light-sensor protein, photoactive yellow protein (PYP). The native chromophore of p-coumaric acid (pCA) of PYP undergoes trans-cis isomerization after absorbing a photon, which triggers proton transfers within the hydrogen-bonding network comprised of pCA and proximal amino acid residues. Although PYP emits little fluorescence, we succeeded to reconstitute an artificial fluorescent PYP (PYP-coumarin) by substituting the pCA with its trans-lock analog 7-hydroxycoumarin. Spectroscopic studies with PYP-coumarin revealed that the chromophore takes an anionic form at neutral pH, but is protonated by lowering pH. Both the protonated and deprotonated forms of PYP-coumarin emit intense fluorescence, as compared with the native PYP. In addition, both the deprotonated and protonated forms show identical λmax values in their fluorescence spectra, indicating that ESPT occurs in the artificial fluorescent protein.
Effect of Modification of Cement-Bonded Particleboards Composition on their Frost Resistance
Authors: Melichar Tomáš , Bydžovský Jiří , Černý Vit
Published: February 2014

The article deals with the study of the effect of modification of composition of cement-bonded particleboards on their frost resistance. Powder waste from the line for production of cement-bonded particleboards was used for preparation of test units. Conditions of storage under alternating freezing and defrosting in combination with effect of water were specifically created. Subsequently, the fundamental physical-mechanical parameters were assessed.
Basic Characteristics of Green Cements of CEM V/A and V/B Kind
Authors: Smrčková Eva , Bačuvčík Michal , Janotka Ivan
Published: February 2014

The reduction of the clinker to addition ratio is becoming of main technological importance because energy saving potential by process optimization at the cements manufacture is almost exhausted. The main properties of composite cements of CEM V/A and CEM V/B kinds of Austrian (AT) and Slovak (SK) provenance with cement clinker contents between 45.1 % (CEM V/A-AT) – 52.9 % (CEM V/A-SK) and 26.9 % (CEM V/B-AT) – 30.9 % (CEM V/B-SK), and reference Slovak CEM I 32.5 R cement containing 95 % of the clinker were tested. The composite cements consist of cement clinker with following additions: blast furnace slag, fly ash and natural pozzolan - zeolite. Basic cement properties (normal consistency, initial and final set, volume stability) and fresh mortar properties (workability, volume density, air content) and strength parameters using standard mortars with W/C of 0.5 are introduced. Laboratory-made CEM V/A concrete specimens (AT and SK) demonstrated 90-day cube compressive strength between 49.8 – 50.9 MPa in water and 45.2 – 48.2 MPa in 60 % R.H. dry air; and those of CEM V/B concretes between 39.7 – 40.9 MPa in water and 26.9 – 38.7 MPa in 60 % R.H. dry air opposite to 53.6 MPa in water and 48.3 MPa of the CEM I 32.5 R concrete kept 90 days in 60 % R.H. dry air at (20 ± 1) °C. The use of CEM V/ (A, B) cements for structural concrete is strongly restricted by normative limitations in European countries. In order to improve this circumstance in Austria and Slovakia, the common research project was solved between 2010 and 2012 with the aim to show application possibilities of CEM V/A and CEM V/B cements for common usage in the structural concrete and ready-mixed concrete.
Study of Effect of Various Types of Cement on Properties of Cement Pastes
Authors: Bodnárová Lenka , Jarolím Tomáš , Hela Rudolf
Published: February 2014

This article studies the effect of various types of cement on rheological properties of cement pastes. Rheological properties are significantly related to workability of concrete and to requirements of mixing water amount and thus affect the development of strength, durability of concrete and resistance of concrete to extreme conditions and to high temperature. This article describes the influence of cement type, type and dose of superplasticising admixtures on development of torque in time. Torque was monitored by the rotational viscometer Viskomat NT. Theoretical part of the article briefly describes the phenomenons that can accompany mixing and processing of cement pastes. Experimental part is focused on monitoring the rheological behaviour of cement pastes of different formulas by monitoring the evolution of torque in time.
Properties of Polyurethane and Epoxy Modified Cementitious Hybrids for Flooring Systems
Authors: Petranek Vít , Hlawiczka Jakub
Published: February 2014

This article focuses on a special kind of polymer modified mortars (PMM) which were developed especially for industrial floorings. These floorings are designed as self-leveling screeds, repair mortars or final coatings of the floor. The article investigates systems of two different binder systems (cement and PU or EP) with polymer-cement ratios between 0,2 to 0,75 [1-. Products of this range could be called cementitious hybrids. Polymers are added into cementitious mortars for different purpose. They are used mainly to improve performance of final product like the workability, adhesion, tensile strength and many other properties of cement materials. They combine several advantages compared to conventional materials like pure epoxy or self-leveling cementitious screeds. Hybrids also show good final properties like endurance against organic and inorganic acids, high abrasion resistance, good slip resistance, toughness etc.. This kind of material can be applied on relative water-saturated substrates or a few days old concrete without cracks or blister formation. It is also known, that properly designed formulations could provide a temporary moisture barrier, which is used to minimize osmotic blister formation in polymer based top coats caused by high moisture content of the substrate. The article elaborates progress of forming co-matrix of these cementitious hybrids. These show some improved properties like waterproofness and improved adhesion to the substrate compared to the conventional cementitious mortar without an organic binder. The general advantages of using this type of material for industrial floorings are also mentioned in the article.
Microwave-Assisted Combustion Synthesis of Nanocrystalline ZnO Powders Using Zinc Nitrate and Various Amount of Organic Fuels as Reactants: Influence of Reactant Parameters - A Status Review
Authors: Nehru L.C. , Sanjeeviraja C.
Published: February 2014

Nanocrystalline ZnO powders have been synthesized by a novel and simple microwave-assisted combustion synthesis method using urea, glycine, carbohydrazine and citric acid as fuels and zinc nitrate as oxidant. The starting materials were directly mixed and a slurry precursor with high homogeneity was formed due to the hygroscopicity of the reactants. The precursor could be ignited at room temperature, resulting in dry, loose and voluminous ZnO powders. An interpretation based on an adiabatic flame temperature, amount of gases produced during reaction for various fuel-to-oxidizer molar ratios (ψ), has been proposed for the nature of combustion and its correlation with the characteristics of as-synthesized product. The variation of adiabatic flame temperature (Tad) with the ψ value was calculated theoretically according to the thermodynamic concept. The reaction process of the precursor was investigated by XRD techniques.
An Integrative Review on Nursing Studies Related to Humor.
Authors: Kim Shin Jeong , Kim Sung Hee , Lee Jung Eun , Kim Hye Young , Yoo So Young , Oh Jina
Published: February 2014

PURPOSE: The purpose of this paper was to describe the attributes of nursing with humor based on an integrative review and to present basic information for developing humor intervention programs for children.METHODS: Using combinations of the terms 'nursing' and 'humor' as key words, the researchers searched four electronic databases to relevant identify studies. Thirteen studies were selected through full text screening of related research published in academic journals from January 1993 to April 2013.RESULTS: Through in-depth discussion and investigation of the relevant literature, three components emerged; 1) using instruments of coping for stress relief, 2) symptoms relief through pleasant feeling, and 3) job satisfaction and work improvement of nurse using humor.CONCLUSION: The results of this study suggest that humor is valuable as a nursing intervention for children and the possibility of bringing about positive results in nursing care if nurses utilize the sense of humor as fully as they can. Therefore, it is critical for nurses to develop a diversity of humor interventions for children as well as measurements to test quality and quantity of humor used in clinical pediatric settings.
Risk factors associated with deciduous tooth decay in Iraqi preschool children
Authors: Al-Mendalawi Mahmood Dhahir , Karam Nadia Taha
Published: February 2014

Introduction: Tooth decay (TD) is common in children with significant consequences on systemic well-being, growth and quality of life, as well as increasing the risk of decay in the permanent teeth. Aim: The aim of the present study is to define risk factors associated with deciduous TD (DTD) in Iraqi preschool children. Materials and Methods: From the 1 st June to 31 st December 2012, a case-control study was carried out on 684 children under the age of 6 years who attended Al-Aulwyiah pediatric teaching hospital in Baghdad. Clinical examination and World Health Organization caries diagnostic criteria for decayed, missing and filled teeth (DMFT) were applied. Data including gender, residence, socio-economic status (SES), parental education level, parental smoking, tooth brushing frequency, type of feeding during infancy and the presence of any systemic disease in the child were sought. Results: The mean DMFT score in the case group was 2.03 ± 1.39, of which decayed teeth formed 1.93. Males had a higher mean DMFT (2.10 ± 1.08) than females (1.96 ± 1.70) but with no statistically significant difference. The study revealed that residence, SES, parental education level and tooth brushing frequency were dependent risk factors significantly associated with DTD. However, gender, parental smoking and pattern of feeding during infancy were not significantly associated with DTD. Only four children with systemic disorders (1.2%), namely asthma and congenital heart diseases, were noticed to have DTD. Conclusion: Pediatricians and dentists could provide dental preventive and screening measures. Confronting relevant risk factors associated with DTD and improving access to oral care services are suggested. In addition, promotion of oral health programs through school curricula is needed.
Adam Smith on Rhetoric and Phronesis, Law and Economics
Authors: Mark Garrett Longaker
Published: February 2014

Following recent scholarship, this article investigates the relationship among Adam Smith's lectures on rhetoric and belles lettres, his Wealth of Nations, the Theory of Moral Sentiments, and his lectures on jurisprudence. According to Smith, the rhetorical theory regarding genre and style improves practical judgment that is central to both economic and legal affairs. Though Smith's lectures on rhetoric feature no overt mention of these legal or commercial applications, when we read these lectures alongside his lectures and writings on jurisprudence and economics, we see that Smith had developed numerous applications for the practical judgment that he taught his students when, under his guidance, they analyzed literary texts. Noting the interrelation among Smith's work on rhetoric, law, and economics allows us to see that others in the Scottish Enlightenment, such as Hugh Blair and Henry Home Lord Kames, similarly found connections among jurisprudence, political economy, and rhetorical theory.
Torture and the Politics of the Sacred
Authors: Bush Stephen S.
Published: February 2014

Of those who deny that it is ever appropriate to torture, even in ticking time bomb scenarios, many appeal to notions like the sacredness of the human person to explain their position. In this article I argue that the sacred does not contribute decisively to resolving the debates about torture in ticking time bomb scenarios. However, the sacred is significant for one important facet of the contemporary problem of torture: the essential role of the populace's attitudes toward torture in ensuring that the prohibition against torture is enforced.
Activist Essayism
Authors: Woolridge Paul
Published: February 2014

Any study of the essay is bound to run into the problem of classification, even more modest inquiries like this one which restrict the genre’s range to twentieth-century Anglo-American literary life. To speak of ‘the essay’, in fact, is already to invoke it as a distinct form of writing, a genre to itself, a rubric under which each individual instance engenders some larger, definitive set of shared criteria. We speak in similar presupposing terms about the novel, the lyric poem, the short story and the epic (among the many others) as literary objects, written forms defined and characterised by larger generic categories. The essay, to be sure, has many such distinguishable features which mark it off as at least a minor literary genre recognisable apart from the rest. Spontaneous, brief, sceptical, ambulatory, tentative, exploratory, subjective, experiential, conversational, fragmentary, elastic, unmethodical and free are some of the more common epithets imputed to its form. As Graham Good observes, ‘many good insights into the potentials of the essay form can be gained from the titles of collections’, especially when drawn from critical and self-reflexive characterisations focused on the essay form itself.1
The Ten Plagues of Egypt
Authors: Wotton Roger
Published: February 2014

The ten Plagues of Egypt described in the Bible were central to the liberation of the Jewish people from the oppression of the Egyptians. The succession of disasters demoralised the Egyptians and were seen as a victory for Jewish monotheistic beliefs. In this essay, natural explanations for most of the Plagues are proposed and a chronology of events is provided. Could the mythological explanation of these arguably natural phenomena still have a profound influence on the modern world?
Carnival and Comedy: on Bakhtin's Misreading of Boccaccio
Authors: Stevens Adrian
Published: February 2014

Bakhtin’s theory of carnival as it is developed in the two seminal studies Rabelais and his World and Problems of Dostoevsky’s Poetics has impacted on a variety of disciplines. Although essentially literary in conception, it claims a historical underpinning. Bakhtin’s fundamental premise is that carnival, understood as the ‘sum total of all diverse festivities, rituals and forms of a carnival type’, was a historical and cultural phenomenon of incalculable importance for the development of European comic narrative from classical antiquity onwards.
What are You Looking at?
Authors: Bentley Peter
Published: February 2014

You’re waiting at the station for your train and you glance at the electronic poster next to you. It notices that you’re looking at it, and from your gaze it works out what you would most like to see. The display changes to show you new brands of mobile phone, and then changes again to show handheld computers as it notices your gaze flicker. You glance at the clock and so it brings up a list of forthcoming trains, then zooms in on yours and shows you exactly how long it will take to arrive. It’s as though it’s reading your mind – but really it’s reading your eyes.
Death and Dying in the Upanisads, Bhagavad-Gita and Caraka Samhita
Authors: Hilton Claire
Published: February 2014

Death, dying and immortality appear at the interface of medical, cultural and religious teaching in many cultures and over thousands of years. Chinese medicine advocated yangsheng (life nurturing), and the desire for immortality was documented during the Han dynasty (206 BCE – 220 CE).1 Galen (129-c216CE) wrote on both medical aspects of long life and philosophical ideas of creation and soul,2 whilst medical ethics today in western cultures not infrequently links to religious beliefs of Christianity and Judaism originating over two millennia ago. This essay explores death and dying in ancient Sanskrit religious and medical texts.
The Future of Poetry
Authors: Wolf Thomas
Published: February 2014

I have seen the future of poetry, and it is in the past. 1984, to be exact, when a precocious algorithm named RACTER published its first book, a tidy little affair called The Policeman’s Beard is Half Constructed. Its weird surrealist illustrations aside, The Policeman’s Beard was notable for two quirks, first, being written by a robot, and second, despite being written by a robot, reading like poetry by John Ashbery.
Hermes 2007 Symposium, Aarhus (Denmark)
Authors: Obradovic Dragana
Published: February 2014

The research interests and presentations of the assembled PhD students at the Hermes Workshop 2007 (hosted this year by Aarhus Universitet) read like an eclectic catalogue of world-wide intellectual curiosities. It was a conference where papers on Michael Ondaatje vied for the audience’s ears and sharp critique alongside an analysis of Jean-Luc Godard’s literary quotation in film, while the poetics of Michel Houellebecq’s novels were presented on the same panel as the travel writing of V.S. Naipaul and W.G. Sebald. If you suggest that there is little variety here among works of contemporary cultural production, there were papers that deepened the linguistic and temporal reach: the conference started with a reflection on literature as philosophy of history and closed with a medievalist’s presentation on the Greek, Ottoman and Russian reports on the fall of Constantinople.
Emblemática y bestiarios en El día de fiesta de Juan de Zabaleta
Authors: Albert Mechthild
Published: February 2014

ABSTRACT: This article seeks to compare emblematics with El día de fiesta (1654/1660) by Juan de Zabaleta, a collection of portraits of manners and characters marked by an encyclopaedic feature that serves the pronounced degree of religious and moral didacticism of the text. It first recapitulates the epistemological basis that Zabaleta has in common with emblematics, namely analogical thinking (Foucault) and the belief in the ‘readability of the world’ (Blumenberg). Subsequently it analyses the allegorical function of certain animals –the panther and the octopus, the ape and the turtle– which Zabaleta refers to as examples of virtues and vices, especially hypocrisy, comparing it to the meaning attributed to the same beasts in emblem books. KEYWORDS: Emblematics, Bestiaries, Juan de Zabaleta, Analogical Thinking, Readability of the World   RESUMEN: El presente artículo se propone comparar la emblemática con El día de fiesta (1654/1660), de Juan de Zabaleta, una colección de cuadros de costumbres cuya fuerte carga enciclopédica está al servicio de un pronunciado didactismo religioso-moral. Primero se recordarán las bases epistemológicas que Zabaleta tiene en común con la emblemática, a saber el pensamiento analógico (Foucault) y la fe en la ‘legibilidad del mundo’ (Blumenberg). Posteriormente se analizará la función alegórica de determinados animales –la pantera y el pulpo, el mono y la tortuga– a los que Zabaleta se refiere como ejemplos de virtudes y vicios, en particular la hipocresía, contrastándola con el mensaje atribuido a la correspondiente fauna en los libros de emblemas. PALABRAS CLAVES: Emblemática, Bestiarios, Juan de Zabaleta, pensamiento analógico, legibilidad del mundo.
The life cycle of Drosophila orphan genes
Authors: Palmieri Nicola , Kosiol Carolin , Schlötterer Christian
Published: February 2014

Orphans are genes restricted to a single phylogenetic lineage and emerge at high rates. While this predicts an accumulation of genes, the gene number has remained remarkably constant through evolution. This paradox has not yet been resolved. Because orphan genes have been mainly analyzed over long evolutionary time scales, orphan loss has remained unexplored. Here we study the patterns of orphan turnover among close relatives in the Drosophila obscura group. We show that orphans are not only emerging at a high rate, but that they are also rapidly lost. Interestingly, recently emerged orphans are more likely to be lost than older ones. Furthermore, highly expressed orphans with a strong male-bias are more likely to be retained. Since both lost and retained orphans show similar evolutionary signatures of functional conservation, we propose that orphan loss is not driven by high rates of sequence evolution, but reflects lineage-specific functional requirements.
Modeling of semi-shell nanostructures formed by metal deposition on dielectric nanospheres and numerical evaluation of plasmonic properties
Authors: Fujimura Ryushi , Zhang Ruzhi , Kitamoto Yoshitaka , Shimojo Masayuki , Kajikawa Kotaro
Published: February 2014

A theoretical model of semi-shell structures formed by metal deposition is constructed for accurate prediction of plasmonic properties. Our model takes account of the influence of metal migration after deposition and the granular nature of the metal. Validity of our model was confirmed by the fact that the plasmonic resonances simulated by our model agreed well with those obtained by experiment. Simulations using the discrete dipole approximation revealed that the semi-shells formed by metal deposition show a larger absorption cross-section than semi-shells fabricated by reshaping of fully-covered core–shells. The deposition type semi-shell is suitable for the photothermal therapy because a larger temperature rise is expected due to greater absorption.
Trap properties of high-k/metal gate pMOSFETs with aluminum ion implantation by random telegraph noise and 1/f noise measurements
Authors: Kao Tsung-Hsien , Wu San-Lein , Tsai Kai-Shiang , Fang Yean-Kuen , Lai Chien-Ming , Hsu Chia-Wei , Chen Yi-Wen , Cheng Osbert , Chang Shoou-Jinn
Published: February 2014

In this study, the impact of aluminum ion implantation on 1/f noise characteristics and random telegraph noise (RTN) in high-k/metal gate (HK/MG) p-type metal–oxide–semiconductor field-effect transistors (pMOSFETs) was investigated. Aluminum ion implantation (Al I/I) into TiN/HfO2/SiO2 was implemented to tune an effective work function (EWF) in pMOSFETs without EOT increase complicated processes. RTN and 1/f results revealed that regardless of the implanted dose, HK/MG devices with Al I/I exhibit lower slow oxide trap densities than the control devices, which are responsible for the reduced trap position (x
t) from the SiO2 interfacial layer (IL)/Si interface. For the HK/MG devices with different implanted doses, no significant differences in trap properties were observed.