bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction of a Supernova with a Circumstellar Disk
Authors: McDowell Austin T. , Duffell Paul C. , Kasen Daniel
Published: March 2018

Interaction between a supernova (SN) ejecta and a dense circumstellar medium (CSM) can power a luminous light curve and create narrow emission lines in the spectra. While theoretical studies of interaction often assume a spherically symmetric CSM, there are observational indications that the gas surrounding some SNe has a disk-like geometry. Here, we use moving-mesh hydrodynamics simulations to study the interaction of an SN with a disk and determine how the dynamics and observable signatures may depend on the disk mass, thickness, and radial extent. We find that simple modifications to standard spherically-symmetric scaling laws can be used to describe the propagation and heating rate of the interaction shock. We use the resulting shock heating rates to derive approximate bolometric light curves, and provide analytic formulas that can be used to generate simple synthetic light curves for general supernova-disk interactions. For certain disk parameters and explosion energies, we are able to produce luminosities akin to those seen in super-luminous SNe. Because the SN ejecta can flow around and engulf the CSM disk, the interaction region may become embedded and, from certain viewing angles, the narrow emission lines indicative of interaction may be hidden.
Two-phase Heating in Flaring Loops
Authors: Zhu Chunming , Qiu Jiong , Longcope Dana W.
Published: March 2018

We analyze and model a C5.7 two-ribbon solar flare observed by the Solar Dynamics Observatory, Hinode, and GOES on 2011 December 26. The flare is made of many loops formed and heated successively over one and half hours, and their footpoints are brightened in the UV 1600 Å before enhanced soft X-ray and EUV missions are observed in flare loops. Assuming that anchored at each brightened UV pixel is a half flaring loop, we identify more than 6700 half flaring loops, and infer the heating rate of each loop from the UV light curve at the footpoint. In each half loop, the heating rate consists of two phases: intense impulsive heating followed by a low-rate heating that is persistent for more than 20 minutes. Using these heating rates, we simulate the evolution of their coronal temperatures and densities with the model of the “enthalpy-based thermal evolution of loops.” In the model, suppression of thermal conduction is also considered. This model successfully reproduces total soft X-ray and EUV light curves observed in 15 passbands by four instruments GOES, AIA, XRT, and EVE. In this flare, a total energy of 4.9 × 1030 erg is required to heat the corona, around 40% of this energy is in the slow-heating phase. About two-fifths of the total energy used to heat the corona is radiated by the coronal plasmas, and the other three fifth transported to the lower atmosphere by thermal conduction.
An Unexpected Detection of Bifurcated Blue Straggler Sequences in the Young Globular Cluster NGC 2173∗
Authors: Li Chengyuan , Deng Licai , Grijs Richard de , Jiang Dengkai , Xin Yu
Published: March 2018

The bifurcated patterns in the color–magnitude diagrams of blue straggler stars (BSSs) have attracted significant attention. This type of special (but rare) pattern of two distinct blue straggler sequences is commonly interpreted as evidence that cluster core-collapse-driven stellar collisions are an efficient formation mechanism. Here, we report the detection of a bifurcated blue straggler distribution in a young Large Magellanic Cloud cluster, NGC 2173. Because of the cluster’s low central stellar number density and its young age, dynamical analysis shows that stellar collisions alone cannot explain the observed BSSs. Therefore, binary evolution is instead the most viable explanation of the origin of these BSSs. However, the reason why binary evolution would render the color–magnitude distribution of BSSs bifurcated remains unclear.
Multi-fluid Approach to High-frequency Waves in Plasmas. III. Nonlinear Regime and Plasma Heating
Authors: Martínez-Gómez David , Soler Roberto , Terradas Jaume
Published: March 2018

The multi-fluid modeling of high-frequency waves in partially ionized plasmas has shown that the behavior of magnetohydrodynamic waves in the linear regime is heavily influenced by the collisional interaction between the different species that form the plasma. Here, we go beyond linear theory and study large-amplitude waves in partially ionized plasmas using a nonlinear multi-fluid code. It is known that in fully ionized plasmas, nonlinear Alfvén waves generate density and pressure perturbations. Those nonlinear effects are more pronounced for standing oscillations than for propagating waves. By means of numerical simulations and analytical approximations, we examine how the collisional interaction between ions and neutrals affects the nonlinear evolution. The friction due to collisions dissipates a fraction of the wave energy, which is transformed into heat and consequently raises the temperature of the plasma. As an application, we investigate frictional heating in a plasma with physical conditions akin to those in a quiescent solar prominence.
A new species of the spider genus Cangoderces (Araneae, Telemidae) from South Africa
Authors: Wang Chunxia , Li Shuqiang , Haddad Charles R.
Published: March 2018

A new species of the spider family Telemidae from South Africa, Cangodercesglobosa sp. n., is diagnosed, described and illustrated. This is the second species of the family to be recorded from the country. Consistent with the habits of most Afrotropical telemids, C.globosa sp. n. was collected by sifting leaf litter in forests.
Pechiney in Australia: A History of Tomago Smelter (1978-1985)
Authors: Mioche Philippe
Published: March 2018

L’aventure australienne commence dans les années 1960 pour Pechiney, attiré par un territoire promis à devenir l’Eldorado de la bauxite. Consciente de cette richesse, l’Australie veut alors la valoriser et développer une industrie locale autour du minerai. C’est ainsi que Pechiney participe dès 1963 à la grande usine d’alumine de Gladstone, exploitée en coopérative par Queensland Alumina Ltd (QAL). Au cours de la décennie suivante, une intégration plus étroite de la filière va toucher la production d’aluminium primaire. Les pouvoirs publics australiens proposent en 1978 à Pechiney de créer une joint-venture afin de construire une usine d’électrolyse sur le site de Tomago. L’opération séduit le producteur français pour trois raisons : l’approvisionnement garanti en alumine, la proximité des marchés asiatiques et la possibilité de vendre sa technologie des cuves d’électrolyse dont il est devenu un des leaders mondiaux grâce à son laboratoire savoyard, le LRF. Après une période d’études et de négociations parfois tendues autour du prix de l’électricité, l’usine entre en activité en septembre 1983. Principal partenaire avec la firme australienne Colonial Sugar Refining, Pechiney apporte son expertise à la nouvelle affaire et conduit les opérations notamment par l’intermédiaire de ses personnels expatriés qui contribuent au démarrage de l’usine et à la formation de la main-d’œuvre locale.
Une jeunesse pour la guerre : la Hitlerjugend (1922-1945)
Authors: Pine Lisa
Published: March 2018

Cet article souligne que l’histoire des enfants-soldats lors de la Seconde Guerre mondiale tient pour une large part au rôle que jouèrent les Jeunesses hitlériennes (Hitlerjugend ou HJ). Il retrace le développement de la Hitlerjugend, mouvement de jeunesse devenu canal de recrutement pour le personnel de guerre. L’Allemagne avait une longue et fière tradition de mouvements de jeunesse au sein de laquelle la HJ occupe une place particulière. Les Jeunesses hitlériennes en vinrent à incarner un esprit ouvertement militaire, que caractérisait une masculinité dure et martiale très différente des autres formes de masculinité qui s’épanouissaient jusqu’alors dans les institutions traditionnelles telles que la famille, l’école et l’église. L’article débute par une exploration de l’histoire des Jeunesses hitlériennes, afin de mettre en contexte la période de guerre, avant d’analyser la formation de ce mouvement, les expériences vécues en temps de guerre et la transformation de ses membres en véritables soldats. Dans la quête d’expansion territoriale ou Lebensraum (« espace vital ») du Troisième Reich, la génération Hitlerjugend joua un rôle important pour la Volksgemeinschaft (« communauté nationale »), la guerre et la conquête de l’empire. Au cœur de la guerre, garçons et filles allemands furent recrutés pour la défense antiaérienne, les premiers parfois envoyés dans les régiments de la Wehrmacht ou de la SS. Enfin, vers la fin de la guerre, de jeunes garçons furent recrutés par la Volkssturm (la milice populaire), défendant l’État national-socialiste jusqu’à la fin en 1945.
La gauche face à la crise de la gouvernance des migrations
Authors: Carême Damien , Palheta Ugo , Binctin Barnabé , Brücker Pauline , Simon Patrick , Vertongen Youri Lou
Published: March 2018

Avec la dite « crise des réfugié·e·s », les gouvernements européens ont confirmé leur obsession sécuritaire dans la gestion des phénomènes migratoires. Loin d’assurer l’accueil et la protection sur le terrain, ils privilégient davantage le tri et le contrôle, et le cas échéant le refoulement, des migrant·e·s, bafouant ainsi les principes fondamentaux d’une Convention de Genève par ailleurs dépassée pour traiter du contexte actuel. Particulièrement absente des débats depuis le fameux « été des migrations » en 2015, la gauche européenne s’est montrée incapable de produire des contre-offensives aux discours de repli sur soi qui font le lit, aujourd’hui encore, d’un durcissement des politiques d’asile. Comment expliquer cette mise en retrait des forces de gauche, institutionnelles ou non, pourtant attendues comme alternatives aux mesures restrictives décidées en matière migratoire ? C’est la question que nous avons posée à deux personnalités de gauche, engagées à leur échelle dans le soutien et l’accueil des migrant·e·s.
« On a fait la révolution pour être libres. Libres de partir » : les départs des harragas de la Tunisie en révolution
Authors: Giusa Caterina
Published: March 2018

Le 28 octobre 2017, un groupe de harragas tunisiens bloqués dans le hotspot de l’île de Lampedusa (Italie) publient un communiqué où ils annoncent le début d’une grève de la faim pour « réclamer [leur] droit de circulation et pour protester contre l’expulsion forcée ». Ces jeunes hommes qui ont quitté la Tunisie après la révolution sont souvent sommés de se justifier, aussi bien du côté de l’Europe que de la Tunisie, alors même que ces migrations peuvent être analysées comme un prolongement du phénomène révolutionnaire.
Calais, carrefour des solidarités citoyennes
Authors: Bouagga Yasmine
Published: March 2018

Au cours des années 2015 et 2016, Calais et sa région ont été des lieux d’intenses engagements citoyens et de mobilisations en solidarité avec les personnes migrantes bloquées à la frontière franco-britannique. Des milliers de volontaires sont venu·e·s apporter leur soutien, individuellement ou au sein d’associations plus ou moins professionnalisées. Si les actions de solidarité sont anciennes, elles ont pris, ponctuellement, une ampleur inédite avec la médiatisation de la « crise des réfugiés », et en réaction à des politiques gouvernementales perçues comme inhospitalières ou défaillantes. Ces soutiens hétérogènes, fortement internationalisés et investis dans les campements mêmes ont réinterrogé les rapports de l’humanitaire et du politique.
Nos voisins les migrants : occupation et vie locale à Place des Fêtes, Paris 19 e
Authors: Simon Patrick , Coutant Isabelle
Published: March 2018

L’occupation par des migrants venant de la Chapelle du lycée Jean Quarré – désaffecté – à Place des Fêtes dans le 19 e  arrondissement de Paris a suscité des réactions contrastées dans le quartier. Aux crispations des uns a répondu la mobilisation d’un comité de soutien qui a accompagné l’occupation. Isabelle Coutant, qui a observé l’installation des migrants dans le lycée et ses conséquences sur la vie locale, revient sur les différents répertoires de mobilisation dans le quartier et les relations entre collectifs de soutien.
What’s in a Word? The Conceptual Politics of ‘Informal’ Street Trade in Dar es Salaam
Authors: Steiler Ilona
Published: March 2018

Focussing on policies towards urban street trade in Dar es Salaam, Tanzania, in this paper I illustrate how despite the widely acknowledged limits to its analytical usefulness, the contested and politically charged concept of the ‘informal economy’ continues to play a vital role in informing strategies of economic and social development on multiple levels of government. I argue that while the negative connotations of the concept continue to cast street trade as an aberration from the norm of formalised economic activity, its usage distracts from the causes and conditions of street trade and leads to a narrow focus on business formalisation, with disastrous consequences for traders and city authorities. I aim at making a conceptual and empirical contribution, structured in two parts: First, starting from Keith Hart’s reflections, I sketch out the discussions surrounding the concept of the informal economy and highlight its socially constructed and normative dimension. In the second part, I delineate the legal status of street trade in Tanzania. The conception of street trade as ‘informal’ is then traced from an international think tank to a national formalisation programme, further to urban planning and law enforcement policies, and finally contrasted with the views of traders.
Strain-Rate Dependence of Compressive Yield Strength of Titanium Grade 4 with Coarse-Grained and Ultrafine-Grained Structures: Experimental Results and Theoretical Calculation
Authors: Smirnov Ivan V. , Konstantinov Alexander Y.
Published: March 2018

The nanocrystalline (NC) and ultrafine-grained (UFG) structures of metallic materials can lead to their extraordinary high strength. However, most of the papers on this topic consider deformation parameters of NC and UFG materials only for the case of quasi-static tensile tests. Characteristics of dynamic strength and fracture of such materials remain unexplored. This paper presents a study of the mechanical behavior of pure titanium Grade 4 with a coarse-grained (CG) and UFG structure under uniaxial compression with different strain rates. The UFG structure was provided using the method of equal-channel angular pressing. The dynamic compression was carried out on a setup with the Split-Hopkinson pressure bar. It is found that in the observed range of strain rates 10–3-3×103 s–1, the yield stress of the CG titanium increases by 20%, and does not exceed the yield stress of the UFG titanium. However, the yield stress of the UFG titanium remains close to a quasi-static value. It is shown that these strain-rate dependencies of the yield strength can be predicted by the incubation time approach. The calculated curves show that at strain rates above 104 s–1 the yield stress of the CG titanium becomes higher than the yield strength of the UFG titanium.
Comparison of Different Extrapolation Models for Materials in the Closed-Extruding Fine Blanking Simulation
Authors: Deng Ming , Niu Jiang Po , Ma Yi Long , Lv Lin
Published: March 2018

The selection of the flow stress model of materials has a great influence on the plastic forming simulation of metal. For closed extrusion fine blanking, selecting the accurate and appropriate material flow stress model can make the finite element simulation closer to the real situation, and the simulation data is more reliable. In order to solve the accuracy problem of finite element simulation closed-extruding fine blanking, 5 types of flow stress fitting curve equations were obtained based on the data of sheet metal tensile test. With the secondary development of finite element software Deform-2D, the circular piece of closed-extruding fine blanking forming process was simulated, whose diameter is 14 mm and thickness is 30 mm. The simulation results of different rheological models were compared after physical experiment being carried out.The results show that Ludwik extrapolation rheological model is suitable for finite element simulation of closed-extruding fine blanking technology, which effectively improves closed-extruding fine blanking simulation accuracy. Lay the foundation for the application of closed-extrusion fine blanking in industry.
Friction and Wear Characteristic of Electroplating Cu Coating on 0Cr18Ni9Ti Stainless Steel
Authors: Wang Wei Hua , Xie Fa Qin , Yao Xiao Fei , Wu Xiang Qing
Published: March 2018

In order to improve wear resistance surface on 0Cr18Ni9Ti stainless steel, Cu coating on the 0Cr18Ni9Ti stainless steel substrate was deposited by electroplating technology. The friction and wear properties of 0Cr18Ni9Ti stainless steel substrate and Cu coating were investigated contrastively. The morphologies of the wear scars were analyzed by scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDS) and scanning probe microscope (SPM), and the wear mechanism was discussed. The results showed that the wear resistance of Cu coatings was significantly improved as compared to that of 0Cr18Ni9Ti stainless steel substrate. The wear scar of 0Cr18Ni9Ti stainless steel substrate showed flaking pit, and its wear mechanism were delamination and abrasive wear. In case of Cu coating, the wear scars showed morphology of plastic deformation caused by adherent copper debris being pressed, and its wear mechanism were delamination and fatigue wear.
Effect of SiC Whiskers on the Microstructure and Thermal Conductivity of Carbon Foam
Authors: Yu Sheng Jie , Chen Zhao Feng , Wang Yang
Published: March 2018

This paper describes the modification of ultralight flexible carbon foam by chemical vapor deposition (CVD) of silicon carbide whiskers (SiCw). The effect of SiC whiskers on the microstructure and the thermal conductivity of carbon foam were investigated by scanning electron microscopy (SEM) and laser flash diffusivity method in a Netzsch LFA427. The results show that the macro-pores (~30 μm) of the carbon foam were divided by the random distribution of SiC whiskers. The diameter of SiC whiskers decreased with decreasing catalyst concentration which resulted in the improved microstructure with a smaller pore diameter (4~6 μm) and a more homogeneous distribution of the pores. The carbon foam reinforced by SiCw exhibits better insulation performance than the pristine carbon foam when the temperature exceeds 200°C.
Enhanced Dielectric and Electrical Properties in Polyurethane Composites with Graphene Nanosheets
Authors: Ardimas  , Putson Chatchai
Published: March 2018

The Electrical properties of polyurethane (PU) filled with graphene nanosheets (GRN) at low frequency is investigated. In last decade, polyurethane elastomers have attracted attention in transducer and actuator applications. The dielectric constant is one of the key factors for increasing actuator ability. Graphene nanosheets as conducting fillers have to be filled to increase the dielectric constant. In order to prove this idea, polyurethane composites with various graphene contents have been characterized by SEM and DSC. And their electrical capability has been measured at various frequencies of 101-104 by using LCR meter. To gain the films, polyurethane composites filled with various graphene contents were prepared by solution casting method. The results showed a well homogenous dispersion of the graphene filler in the polyurethane matrix. In addition, it was found that the glass transition temperature (Tg) of the PU/GRN increase as the content of filler increased and it can be affected the interfacial polarization between PU matrix with the GRN fillers. Therefore, it is found that graphene in the polyurethane matrix exhibit high enhanced the electrical properties and the optimal dielectric constant at 2wt% graphene of 9.74.
Nitrate Reduction Using As-Synthesized Nanoparticles Zero Valent Iron (NZVI) at Ambient Environment
Authors: Lai Mun Kou , Teo Hiu Hong , Satheshkumar Sauandaraju , Ng Chun Kit
Published: March 2018

Nitrate removal or denitrification, involves reduction of nitrate into nitrogen and oxygen. The use of nanoparticles zero valent metals for denitrification receives great attention as they have been proven to be effective and environmentally safe. In this work, the nanoparticles were prepared by reducing the metals salts, dissolved in a mixed solution of water and ethanol, using sodium borohydrate. The nitrate reduction reaction took place in an ambient environment – room temperature, neutral pH and aerobic condition. Results from the experiments carried out showed that nitrate has been successfully reduced up to a maximum of 40% in all the samples without an increase in the pH of the solution, a strong indication that ammonia was not produced. As for the study on the reactivity of the recycled NZVI, the samples synthesized with 4:1 (v/v) ethanol/water and using 9: 1 (v/v) ethanol/water, the reactivity of the iron is similar to the fresh NZVI for the first two hours of the study.
Enhanced Adsorption Properties of Ag-Loaded β-Zeolite towards Toluene
Authors: Temerev Victor , Vedyagin Aleksey , Iost Kristina , Afonasenko Tatyana , Tsyrulnikov Pavel
Published: March 2018

Two series of Ag-loaded β-zeolites with silica/alumina ratio of 25 and 36 were prepared by ion exchange technique. The silver loading was varied in a range of 2-10 wt%. The samples were characterized by low-temperature nitrogen adsorption, Infrared and UV-vis spectroscopy, and transmission electron microscopy. Adsorption/desorption properties of zeolites were examined using a specially designed setup. Toluene was used as a model hydrocarbon. It was found that adsorption capacity of zeolites grows up along with silver content increase till 8%, and reduces then. According to data of physicochemical methods, at low loading the silver exists in cluster and ionic forms, while at high loading agglomerated particles predominate, which worsens the adsorption properties.
Assessment of Corrosion Behavior in Artificial Saliva of Wires for Orthodontic Applications
Authors: Phukaoluan Aphinan , Khantachawana Anak , Kaewtatip Pongpan , Dechkunakorn Surachai
Published: March 2018

The aim of this study, the corrosion behavior of TiNiCu in artificial saliva (pH5.35) at 37°C was assessed by the use of electrochemical methods. Ti50Ni43Cu7 (at%) used in this study were made from ingots prepared by the vacuum arc melting (VAM) method. The furnace was purged with argon gas during melting. All melted ingots were then homogenized at 800°C for 3.6 ks. Open circuit potential (OCP) was monitored at 3.6 ks followed by potentiodynamic techniques. The results showed that all chemical composition of orthodontic wires by EPMA were Ti, Ni, Cu, Cr, Fe and Mn. Surface roughness was measured in order to ensure that TiNiCu and SS was significant difference which might affect corrosion resistance. It was seen that TiNiCu orthodontic wires, presented a good corrosion resistance, compared to the stainless steel, probably due to the formation of a protective oxide film mainly constituted by titanium oxide.
Numerical Studies on Low-Velocity Impact Failure Response of Al 1100 under Blunt and Hemispherical Impactors
Authors: Sahu Sonika , Ansari Mohd Zahid , Cho Chong Du
Published: March 2018

Numerical simulation is performed to study the deformation and failure modes of Al 1100 plate of 2.4 mm thickness, subjected to low-velocity impact. Blunt and hemispherical nose shaped impactors are used in this study. The quasi-static tensile test is performed at a strain rate of 0.01/s to obtain the Johnson-Cook material parameters which are used in numerical simulation software, ABAQUS/CAE to perform impact analysis. Mesh convergence study is carried out to decide the appropriate number of elements for numerical analysis. The impact behavior of Al 1100 plate for each impactor shapes are studied at 22 J impact energy. Result indicate that increased in the nose radius of impactor will increase the amount of deformation energy for aluminium plate.
Goss Texture Formation by Asymmetric Rolling in Steel Sheet
Authors: Kim In Soo , Nam Su Kwon , Kim Gwang Hee , Lee Dong Nyung
Published: March 2018

The Goss texture, or {110}<001>, shows soft magnetic property due to the <100>. Therefore, it is one of the most important texture in Si steels. The Goss texture is one of the shear deformation texture in steel which has bcc structure. During the asymmetric rolling, shear deformation is imposed on steel sheets. To obtain the Goss texture, the carbon and Si steel sheets were asymmetrically rolled by 50-85% reduction in thickness at room temperature and at 770 °C. The asymmetric rolling of steel sheets gave rise to the well-developed Goss texture to them.
An Error Compensation Method for Rectangular Window Based on NURBS Reconstruction Theory
Authors: Li Dong Xia , Wang Ai Min , Ren Peng Hao
Published: March 2018

Aiming at the error compensation problem for rectangular window, this paper presents a method of compensation for rectangular window based on NURBS (Non-Uniform Rational B-Splines) reconstruction. In the method, the machining surface is digitally obtained by means of on-machine measurement. The measured data are divided into four regions and different error compensation schemes are used for different regions. The adaptive compensation of the machining error calculated based on NURBS reconstruction theory is achieved by modifying the coordinates of the tool point in the cutter location file. The automation of error calculation and compensation is implemented by software development based on Visual Studio 2012. At the end of the paper, a compensating tool path is emulated in VERICUT. The results show our method is feasible.
Modal Stress Analysis of a Cracked Woven Composite Beam under Compression
Authors: Yetmez Mehmet
Published: March 2018

In this study, modal stress analysis of carbon fiber plain weave cracked composite beams under compression is considered. General-purpose finite element code MSC. Marc is used for the finite element beam models. Before understanding the compression effect on the beam, dynamic characteristics of the models are compared with the experimental evaluations. Investigation of quasi-static and dynamic (equivalent von Mises stress and elastic strain energy density) behavior of the plain weave cracked beams with two different thicknesses under compression is examined numerically. Results are given in tabular and graphical form.
Thermal Conductivity of Aerated Concrete Based on Response Surface Method
Authors: Ulykbanov Anuar , Sharafutdinov Eldar , Ramazanova Elmira , Shon Chang Seon
Published: March 2018

Aerated concrete (AC) is widely used in the construction industry due to lightweight and advanced thermal properties. In this research, thermal conductivity (λ) of non-autoclaved AC was characterized with Response Surface Methodology (RSM). The effect of fine aggregates with different Al2O3 contents on the minimal λ value was analyzed using RSM. Test results show that sand with higher Al2O3 content has more influence on lower λ of AC. The regression models were significant and applicable to analyzation and prediction of λ of AC with good accuracy.
Mechanical Properties of Herbal Patches from Chitosan-Based Polymer Blends for Medical Applications
Authors: Suksaeree Jirapornchai
Published: March 2018

Recently, Thai herbs are widely used as medicine to treat some illnesses. Zingiber cassumunar Roxb., known by the Thai name “Plai”, is a popular anti-inflammatory, antispasmodic herbal body and muscle treatment. This research aimed to prepare herbal patches that incorporated the 3 g of crude Z. cassumunar oil. The herbal patches made from different polymer blends were 2 g of 3.5%w/v chitosan and 5 g of 20%w/v hydroxypropyl methylcellulose (HPMC), or 2 g of 3.5%w/v chitosan and 5 g of 20%w/v polyvinyl alcohol (PVA) using 2 g of glycerin as a plasticizer. They were prepared by mixing all ingredients in a beaker and produced by solvent casting method in hot air oven at 70±2oC. The completed herbal patches were evaluated for their mechanical properties including Young’s modulus, ultimate tensile strength, elongation at break, T-peel strength, and tack adhesion. The thickness of blank and herbal patches was 0.263-0.282 mm and 0.269-0.275 mm, respectively. Young’s modulus, ultimate tensile strength, elongation at break, T-peel strength, and tack adhesion were 104.73-142.71 MPa, 87.92-93.28 MPa, 154.39-174.98 %, 3.43-4.88 MPa, and 5.29-7.02 MPa, respectively, for blank patches, and 116.83-147.28 MPa, 89.49-100.47 MPa, 133.78-159.27 %, 2.01-3.98 MPa, and 4.03-5.19 MPa, respectively, for herbal patches. We prepared herbal blended patches made from chitosan/PVA or chitosan/HPMC polymer matrix blends incorporating the crude Z. cassumunar oil. They had good mechanical properties that might be developed for herbal medicinal application.
Design and Fabrication of Thick Film Dissolved Oxygen Sensor Based on RuO2 Working Electrodes for Water Quality Monitoring
Authors: Wiranto Goib , Widodo Slamet , Hermida I Dewa Putu , Manurung Roberth V. , Sugandi Gandi , Arifin Zaenal , Wiendartun
Published: March 2018

A Dissolved Oxygen (DO) sensor has been designed and fabricated on an 8.5 x 22.5 mm Alumina substrate using thick film technology. The structure of the sensor device consisted of AgPd working/counter electrode, Ag/AgCl reference electrode, RuO2active layer, KCl electrolyte, and TiO2membrane. Formation of the Ag/AgCl reference electrode was done by chlorination of Ag layer using FeCl3, and the TiO2membrane was formed by screen printing of TiO2paste. Measurement was done to study the sensor’s performance based from the current-voltage characteristics between 1.1 – 1.6 V. The results showed that a stable diffusion current was obtained when the input voltage was 1.4 V, resulting in the best sensor performance with a sensitivity of 0.560 μA l/mg and a stable step response time of 4 min. The device showed highly potential to be used as candidate for online water quality monitoring system.
Effect of S:Fe Molar Ratios on the Direct Formation of Nanocrystalline Pyrite FeS2 Thin Films by Chemical Spray Pyrolysis under a Low Substrate Temperature (< 300 °C) for Biosensor
Authors: Cheng Bo Ci , Shi Jen Bin , Wu Cheng Han , Chen Kuan Ping , Wu Po Feng , Lee Hsuan Wei , Lin Hsien Sheng , Cheng Fu Chou
Published: March 2018

The FeS2films were deposited by using the spray pyrolysis method using mixed aqueous solutions of CH4N2S and FeCl3, with different S:Fe molar ratios. The homogeneous FeS2nanocrystalline films with good crystallinity were synthesized. The structure, composition, and properties of these films were very sensitive to the S:Fe molar ratios. The direct transition of the pyrite FeS2films were about 0.9 - 1.25 eV. High absorption coefficients and suitable band gaps were observed. FeS2thin films were synthesized for new biomaterial applications such as glucose.
Energy Absorption Capacity of Basalt Sandwich Composite Cylinder Subjected to Axial Compression Loadings
Authors: Roslan Mohd Nazrul , Yahya Mohd Yazid , Ahmad Zaini , Abdul Rashid Azrin Hani , Wang Wen Xue
Published: March 2018

In this report presented the investigation of axial progressive compression on sandwich composite cylinder made from basalt fibre reinforced composite tube as skins and polyurethane (EPU) foam as core of the structure. The effect of braid orientation angle of the sandwich skins and foam core thickness were evaluated on the parameter performance namely peak force, average force, total energy absorption, crush force efficiency, and specific energy absorption. The primary failure mode observed was progressive failure fibre cracking and tube’s wall folding and crumping. Experiment result showed that the effect of outer wall braid angle of sandwich tube structure was the dominant factor contributed to high energy absorption capacity. Furthermore, the foam thickness has no significant influences on the SEA value; however, the total diameter size of sandwich tube skins was.
Sintering Temperatures Investigation on the Electrical Characteristics of Fe2TiO5/MnO2 Ceramics-Based NTC Thermistor
Authors: Wiendartun  , Rusdiana Dadi , Setiawan Andhy
Published: March 2018

Fabrication of Fe2TiO5 pellet/disk ceramics-based NTC thermistor has been performed, in order to know the effect of sintering tempertures on the electrical characteristic of 1.0 mole % MnO2 doped-Fe2TiO5 ceramics. These ceramics were made by mixing commercial powders of Fe2O3, TiO2 and MnO2 with proportional composition to produce Fe2TiO5 based ceramic. The raw pellet was sintered at 1100 °C, 1200 °C and 1300 °C temperature for 2 hours in air. Analysis of the microstructure and crystal structure were performed by using a scanning electron microscope (SEM) and x-ray diffraction (XRD) respectively. XRD pattern showed that all of Fe2TiO5 ceramics made ​​at various sintering temperatures are orthorhombic The SEM images showed that the grain size of pellet ceramics increase with increasing sintering temperatures. From electrical data that was measured at temperature 30-300 °C, showed that the addition of sintering temperature decreased the thermistor constant (B), activation energy (Ea), thermistor sensitivity (α) and room temperature resistance (RRT). Thermistor constant (B) of the ceramics was relatively big of 5778 K to 6707 K. The value of B indicated that ceramics made in this work fit the market requirement for NTC thermistor.
Mechanical Properties and Microstructure of the Magnesium Alloy Mg-6.8Y-2.5Zn-0.5Al Produced by Casting and Hot Rolling
Authors: Neh Kristina , Ullmann Madlen , Kawalla Rudolf
Published: March 2018

In recent years, magnesium alloys have been received much attention as important structural materials for lightweight components in automotive, electronic and space industries because of the low density, high specific strength, high damping capacities and good casting properties. Among various magnesium alloys, rare earth (RE) containing alloys are known to show high strength, excellent creep resistance, and good thermal stability. Long period stacking ordered structures (LPSO) being responsible for the improved property profile in some Mg–RE alloys. One promising system are the Mg-Y-Zn alloys, which are predominantly processed via extrusion. Only a few studies are focused on hot rolling. However, these works are confined to rolling temperatures between 350 °C and 420 °C. The present paper summarizes the development of a rolling technique including pass schedule and heat treatment for the magnesium alloy Mg-6.8Y-2.5Zn-0.5Al in as-cast condition in order to produce sheets with a final thickness of 2.5 mm. The investigations are accompanied by the characterization of the microstructure as well as the determination of the mechanical properties.
Conceptualisation of African primal health care within mental health care
Authors: Nare Neo E. , Pienaar Abel J. , Mphuthi Ditaba D.
Published: March 2018

Background: It is believed by western education systems that the first contact should be with the nurse in primary health care. However, it is not the case. Therefore, the researcher attempts to correct this misconception by conceptualising the correct beginning of health seeking behaviour in an indigenous African community, namely African Primal Health Care (APHC). ‘Primal’ was coined during a colloquium by Dr Mbulawa and Seboka team members; however no formal conceptualisation took place, only operational definition. Due to the study scope, conceptualisation is narrowed to mental health, but this concept is applicable in the broader health context. The research purpose was to contribute to the body of indigenous knowledge systems to advocate towards co-existence of primal health care and mental health care.Aim: Formulate APHC within a mental health care context.Objectives: To explore philosophical grounding of APHC and describe epistemology of APHC. To analyse and crystallise the exploration to establish understanding within mental health and conceptualise APHC within mental health care to enhance co-existence.Methodology: Narrative synthesis, concept analysis (qualitative design). Lekgotla was used as a method of data collection and data were analysed using Leedy and Ormrod’s five steps of data analysis.Results: APHC is a health care system that existed in Africa prior to the introduction of the western health care system. It is based on the African belief system and practices. The practices come from the community, for the community and are authenticated by the community. APHC uses a holistic approach and the family and community are involved in the healing process.
Challenges in implementing continuous support during childbirth in selected public hospitals in the North West Province of South Africa
Authors: Spencer Nobelungu S. , Du Preez Antoinette , Minnie Catharina S.
Published: March 2018

Background: According to a Cochrane review, continuous support during childbirth increases the mother’s chances of a vaginal birth without identified adverse effects. However, this evidence-based practice is not universally implemented. The objective of the study was to identify challenges encountered in implementing continuous support during childbirth in public hospitals in the North West Province of South Africa. Method: An explorative, descriptive and contextual qualitative approach was used. The data were collected during 2013 by conducting focus group interviews with 33 registered midwives who had worked in maternity units in three selected public hospitals in the North West Province for at least two years. Results: Midwives identified challenges that negatively impacted the implementation of continuous support during childbirth at organisational and interpersonal levels. At the organisational level, challenges included human resources, policies and guidelines as well as the architectural outlay of the maternity units. The personal challenges related to communication and attitudes of nurses, patients and their families.  Conclusions: Organisational and personal challenges had a negative impact on the provision of continuous care during childbirth.
Exchange of wife for social and food security: A famine refugee’s strategy for survival (Gn 12:10–13:2)
Authors: Tushima Cephas T.A.
Published: March 2018

This essay studies Genesis 12:10–13:2 with a literary close reading approach that takes seriously the text’s literary, historical and theological constituent elements. After a brief history of interpretation, it situates the narrative in its historical context, which is followed with a narrative critical reading of the text. The analysis of the text unveils the dissimulations of Abram, who manipulated his wife, Sarai, into thinking her beauty posed a threat to him, while his primary motive rested with the pursuit of economic gain in the face of the severe famine that had impoverished him in Canaan. Abram also succeeded in making Pharaoh believe that Sarai was his sister, on which account he exchanged her for material again. This analysis affords insight into the insecurity, anxiety, feelings of alterity of immigrant populations in their liminal conditions, the mistrust of immigrants by the state and host communities, and the ensuing power play (including sexual politics and/or commerce) with its concomitant perils. Through these, the passage speaks anew to contemporary communities of faith in view of the prevalent and ever-increasing migratory trends of the 21st century.
Economic migration and the socio-economic impacts on the emigrant’s family: A case of Ward 8, Gweru Rural district, Zimbabwe
Authors: Ndlovu Everson , Tigere Richard
Published: March 2018

Gweru Rural district in the Midlands province of Zimbabwe has witnessed an increasing number of outward migrations of breadwinners, leaving behind a desperate environment for families. This study was motivated by the realisation that most of the sick left behind, the elderly and children would visit the health centres unaccompanied, risking taking prescribed drugs incorrectly, thus further compromising their health. The study sought to establish the socio-economic effects of international migration on family members left behind in ward 8 of Gweru Rural. The study adopted a qualitative case study approach. Focus group discussions, questionnaires and structured individual interviews were used to elicit for data. Non-probability sampling design was used because of small samples available. Convenience and purposive sampling techniques were particularly used. Data were manually analysed and presented both qualitatively and quantitatively. The study revealed that international migration particularly to South Africa, especially by non- professionals, was not yielding the much expected economic gains; instead it was characterised by more negative social effects on the emigrant’s family. The study recommends that emigrants should consider migrating with their loved ones and, where it is not feasible, to put in place sound alternative caregiving arrangements. The study has provided an insight into international migration and its effects on left-behind families. However, a more comprehensive and quantitative survey remains critical to delving deeper into this migration phenomenon, particularly on how both the emigrant and left-behind spouses handle the issue of conjugal rights.
A geographic information system-based approach of flood hazards modelling, Paschim Medinipur district, West Bengal, India
Authors: Dandapat Kishor , Panda Gopal K.
Published: March 2018

From the beginning of civilisation, human beings have preferred living on the river banks which have been the most vulnerable areas of flood hazards and consequent disasters. During the monsoon period, in many developing countries of south-east Asia, flood hazards and disasters have been a serious challenge for their development. Most of the rivers exceed their normal channel capacity attaining the flood stage and frequently overflow their banks, causing great havoc to the life and property of the people. Flooding is a very serious problem in many districts of West Bengal. The prime concern of delineation of flood-prone areas is to regulate the land use in the flood-prone areas to restrict damage potential and also mitigate the negative effects of floods on people and the economy. In a regulated way, flood-prone areas are required to be developed. Because, on one hand, it is to be ensured that existing hazard and flood damage potential do not increase and new developmental works become a step towards mitigation of disaster risk. In a perspective view, the demarcation and identification of flood-prone areas of different magnitudes, frequencies and return periods on a large-scale map seem to have great importance. Satellite-derived flood maps from 2007 to 2016 have been applied to form a flood frequency map and the same as a group of flood depth maps has been employed to produce the Flood Damage Map for depth data of flood. Finally, the modelling of flood hazards has been directed by envisaging amalgamation of Flood Depth and Flood Affected Frequency. Then the final flood hazard map amalgamated with population and housing data has been used to ascertain the flood disclosure for these two components. Flood hazard analysis in the study area revealed that 24% of the population has been located in high flood hazard zones, where 39% of human settlements are located in different flood hazard zones.
Research trends in the South African Journal of Human Resource Management
Authors: Pietersen Charlotte
Published: March 2018

Orientation: A comprehensive framework for research in human resource management (HRM) in terms of fundamental knowledge orientations was found lacking.Research purpose: The aim was to perform a typological review of research trends in the field of HRM, specifically of publications in the South African Journal of Human Resource Management (SAJHRM).Motivation for the study: No previous research in the field of HRM in South Africa adopted a fundamental theory of knowledge.Research design, approach and method: A qualitative design was followed, consisting of a documentary analysis of articles that were published in the SAJHRM for the period from 2003 to 2015. A detailed content analysis of published articles was performed in terms of a number of criteria, namely knowledge type, race, gender, authorship, author contribution and representation according to author institution and country of origin.Main findings: An analysis of a final selection of 289 articles indicated that research in the SAJHRM was mostly on the following lines: research was mostly of the hypothesis-testing (Type II) knowledge type; involved multiple authorship; and was conducted by mostly white, male researchers, based at a relatively few South African academic institutions.Practical and managerial implications: The SAJHRM should, in partnership with the HRM profession, promote and publish research that more prominently addresses the gap between academic HRM and HRM practice, especially in terms of the participatory or action research (Type IV) mode of knowledge generation.Contribution: The present analysis of research trends in the SAJHRM provides a broader and more nuanced perspective on forms of research required for the HRM field in South Africa.
Investigating the impact of a combined approach of perceived organisational support for strengths use and deficit correction on employee outcomes
Authors: Els Crizelle , Mostert Karina , Van Woerkom Marianne
Published: March 2018

Orientation: The positive psychology paradigm suggests a balanced focus on employee strengths and deficits. However, an overemphasis on strengths has raised questions regarding the value of a focus on strengths use, deficit improvement or a combined approach with a balanced focus on both.Research purpose: The primary objective was to examine whether perceived organisational support (POS) for strengths use, POS for deficit improvement or a combined approach would be the strongest predictor of work engagement, learning, job satisfaction and turnover intention.Motivation for the study: In the literature, there is little empirical evidence to support an approach where both employees’ strengths are used and their deficits improved.Research design, approach and method: This study was conducted among 266 teachers from four public schools in the Western Cape. A cross-sectional survey design was used.Main findings: The results suggest that both strengths use and deficit improvement are important predictors of work engagement, learning, job satisfaction and turnover intention. Learning was higher and turnover intention lower for individuals experiencing a combined approach compared to those believing that their school did not support them in either using their strengths or improving their deficits. Furthermore, a combined approach was associated with higher job satisfaction than a strengths-based approach, and a deficit-based approach was shown to be associated with higher levels of work engagement and lower turnover intentions compared to an environment where neither employees’ strengths nor deficits were addressed.Practical or managerial implications: The results urge organisations to invest an equal amount of resources in their employees’ strengths and deficits, as opposed to neglecting either one. Such a combined approach may be associated with increased work engagement, learning and job satisfaction and lower turnover intention.Contribution: This study provides empirical evidence that supports a combined approach where both employees’ strengths are used and their deficits developed.