bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Frequency on the Fatigue Behavior of IN718 Superalloy
Authors: Du Jin Hui , Lu Xu Dong , Deng Qun
Published: January 2017

IN718 alloy possesses excellent mechanical properties at high temperatures, good process ability, therefore, it has been widely used in aero engine turbine disks, compressor disks, and power turbine shafts (i.e., rotating components). The fatigue properties of the alloy are a key factor that determines the safety and reliability of the engine. In this paper, the fatigue properties of IN718 alloy are investigated under low-and middle-frequency conditions at 600 °C and 455 °C, the initiation of fatigue cracks, and the relation between fatigue life and grain size are discussed. The results show that the carbides response as a crack initiation site at low-frequency fatigue condition (1 Hz), and string-type or heap-type carbides distribution promotes crack propagation and shortens fatigue life, the twin boundaries in large grains are act as a crack initiation site at middle-frequency fatigue condition (10 Hz). The grain size is smaller, and the low cycle fatigue properties of the alloy are better.
Research on the Mechanical Performance and Crack Defects Assessment of X65 Marine Pipeline Welding Joint
Authors: Hu Yan Hua , Wang Yu Lei , Niu Hu Li , Tang De Yu , Li Chun Run , Li Jian
Published: January 2017

In order to study the influence of different types of weld defects, such as slag inclusion, porosity, incomplete fusion, incomplete fusion, burn through, crack on the mechanical performance of X65 marine pipe welding joint (Φ323.9 x 16 mm), the test on the mechanical properties of static tensile, fracture toughness CTOD and fatigue life were carried out to achieve the maximal defect tolerance size allowed in this paper. Research shows that the existence of crack defects would significantly reduce the fracture strength and the fatigue life of welded joint, the application of the maximal defect tolerance size allowed based on crack defects assessment can provide referential basis for the safe and stable operation of marine pipelines.
Mechanistic Insight into H2S Adsorption and Dissociation on MoP(010): A Density Functional Investigation
Authors: Li Gui Xia , Zhu Hou Yu , Zhao Lian Ming , Guo Wen Yue , Lu Xiao Qing , Ma Hui Fang , Yu Yan Chen
Published: January 2017

H2S adsorption and dissociation on MoP(010) were investigated using density functional theory (DFT) together with periodic slab models. Several different possibilities for H2S, SH, S and H adsorption were considered. Our results show that the H2S, SH and H prefer to adsorb at bridge site, while S adsorbs preferentially at hcp and bridge sites. Additionally, the optimum co-adsorption configurations for SH/H and S/H were determined. The results indicate that the co-adsorbed species repel each other slightly on MoP(010) surface. Finally, the potential energy profile of H2S dissociation on MoP(010) surface was given out. The dissociation energy barriers of the S–H bond scission exhibit that H2S prefers to dissociate on MoP(010) surface. When compared with MoP(001) surface, the obvious differences in H2S decomposition arise demonstrate that the MoP-based catalysts are structure-sensitive.
The Improvement of Deformation Analysis for Circular Tunnel Based on Hoek-Brown Criterion in Strain-Softening Rock Mass
Authors: Han Jian Xin , Wang Lei , Jiang Bei , Zheng Chun Mei
Published: January 2017

To overcome the defect that the support pressure is required to be measured or supposed in elasto-plastic analysis in strain-softening rock mass, by the connection of the support pressure imposed on surrounding rock mass, without assuming the support pressure is known a priori, an improved model of solving plastic radius and the distribution of radial displacement around the circular tunnel is proposed. Based on Hoek-Brown yield criterion, the results obtained by strain-softening model are compared with those of elastic perfectly brittle and elastic perfectly plastic models. The examples reveal that the difference of plastic radius obtained by the three models is comparatively smaller, but the difference of radial displacement is comparatively larger. The proposed model overcomes some defects of the previous studies in deformation analysis for tunnel.
Application of Hypotheses Theory during Creep Curves Assesment
Authors: Reznicek Martin , Hylova Lenka , Stanek Michal , Ovsik Martin
Published: January 2017

This article is focused on a test assesment with a low repeatability, which is typical of its financial and time severity. In the introduction of this work the assessment of the current state of the solved problem concentrated on the creep test assesment is carried out, which is typical of its low repeatability. These results are subsequently graphically confronted with the subjective assessment of the observer and using Mann-Whitney test. This test is there used for finding if measured data come from the same basic file or come from the selected confidence level. The results show the significance of using this test, which is calculated with certain probability.
Phase Purity and Thermoelectric Properties of Type-I Clathrates Ba8CuxSiyGe46-x-y (4 ≤ x ≤ 6.5, y = 0 and 5.15 ≤ x ≤ 6.425, 2.05≤ y ≤ 36.9)
Authors: Dong Yue , Yan Xin Lin , Tang Zhao Hui , Ding Xue Yong , Sun Xu Dong , Paschen S.
Published: January 2017

Type-I clathrates have been considered as very promising thermoelectric (TE) materials thus attracting attention widely. Here we report new clathrates Ba8CuxSiyGe46-x-y (4≤ x ≤ 6.5, y = 0 and 5.15 ≤ x ≤ 6.425, 2.05≤ y ≤ 36.9), focusing on their phase purity and TE properties. Our results show that samples prepared by arc melting followed by annealing are multi-phases alloys. The composition of the clathrate phase is also inhomogeneous. This indicates that the kinetic factor dominates the reaction of forming the clathrate phase during element-melting and sample-annealing. We select three compositions in these two series of samples, which have less impurity and better composition homogeneity for the clathrate phase, and the annealed alloys are furthered processed by ball milling (BM) and powder-solidification (either by hot pressing (HP) or by spark plasma sintering (SPS)) for TE properties investigations. The BM and HP/SPS processes can improve the phase purity and homogeneity. The TE measurements show that the Si-substituted samples have better performance than the Ge-based sample, mainly by decreasing the electrical resistivity. This indicates that the elemental substitution may be still an effective way to improve the TE performance of clathrates.
Synthesis and Photochromic Properties of 1-[2-Cyano-1,5-Dimethyl-4-Pyrryl]-2-[2-Methyl-5-(1,3-Dioxolane)-3-Thienyl] Perfluorocyclopentene
Authors: Feng Er Ting , Lu Rui Min , Fan Cong Bin
Published: January 2017

A new unsymmetrical photochromic diarylethene 1-[2-cyano-1, 5-dimethyl-4-pyrryl] -2-[2-methyl-5-(1, 3-dioxolane)-3-thienyl] perfluorocyclopentene has been synthesized, and its properties including photochromism, kinetics and fluorescence have been investigated in detail. The results showed that its photochromic behaviors could be modulated by UV/Vis light, changing from colorless to blue in acetonitrile solution.
Synthesis, Photochromism Properties of 1-(1,5-Dimethyl-2-Pyrrolecarbonitrile)-2-[2-Methyl-5-(4-Aminomethyl)Phenyl-3-Thienyl] Perfluorocyclopentene
Authors: Li Gang , Li Xue , Liu Gang , Zhang Dao Bin
Published: January 2017

A new unsymmetrical diarylethene derivative 1-(1, 5-dimethyl-2-pyrrolecarbonitrile) -2-[2-methyl-5-(4-aminomethyl) phenyl-3-thienyl] perfluorocyclopentene (1o) was designed and constructed successfully. Its optoelectronic properties have been discussed systematically, such as photochromic, kinetics experiments in acetonitrile solution and PMMA.
Study on the Synthesis and Application of a Material 1-[2-Methyl-5-Phenyl-3-Thienyl]-2-[2-Methyl-5-(3-Aldehyde-4-Methoxy)-3-Thienyl] Perfluorocyclopentene
Authors: Lu Rui Min , Li Shu Ying , Cui Shi Qiang
Published: January 2017

A novel photochromic diarylethene was successfully synthesized, which is named 1-[2-methyl-5-phenyl-3-thienyl]-2-[2-methyl-5-(3-aldehyde-4-methoxy)-3-thienyl] perfluorocyclopentene. The compound showed good photochromic behavior. Upon irradiated with UV/vis lights, the color of the compound could be changed between colorless and blue, accompanied by a fluorescence switch between the open-ring isomer and closed-ring isomer.
Facile Self-Assembly Synthesis of Hierarchical 3D Flowerlike Calcium Citrate Microspheres
Authors: Li Jun Feng , Gao Yang , Zhong Liang Zhao , Liu Yu Qing , Liu Heng Quan , Zou Qin , Lai Xue Fei
Published: January 2017

Three-dimensional (3D) flowerlike calcium citrate microspheres assembled from nanosheets were successfully synthesized through a soft chemical method. The phase structure, morphology and microstructure of the synthesized products were characterized by the SEM, XRD, infrared and Raman spectroscopy. The characterization results indicated that the well-organized products with the diameter ranging from 10 to 30μm were composed of nanosheet precursors (50~500nm-50~200nm-8~30nm). The (200) crystal plane was the preferential growth face in the self-assembly process and the sheet precursors could be progressively transformed into consecutive strip with continuous heating treatment. The novel flowerlike calcium citrate microspheres with controllable morphology shows potential application prospect in biomaterials or other fields.
Reduced Graphene Oxide Paper: Fabrication by a Green Thermal Reduction Method and Preliminary Study of its In Vitro Cytotoxicity
Authors: Wang Xin , Li Peng , Luedecke Claudia , Zhang Qiang , Wang Zan , Jandt Klaus D.
Published: January 2017

Graphene films have been intensively explored because of their unique mechanical and physicochemical properties for potential applications in field of tissue engineering and implants. However, for biomedical applications, it is necessary to fully understand the toxicity and biocompatibility of the prepared graphene films since different synthesis method might lead to different biological properties. Here we report a step-by-step thermal reduction method of preparing reduced graphene oxide (rGO) film directly on various substrates at low heating temperature (below about 200 °C) without requiring any chemical reduction agent like hydrazine or other reductants (therefore we call it green method). Slowly heating GO hydrosol that was coated on the surface of a glass cell-culture dish or inside of a polypropylene tube from room temperature to 60, 100, and 160 °C for 12 h, respectively, a shiny and flat surface without crumpled structure or tiny pores was formed. We peeled it off from the substrate to explore its cytotoxicity. The results exhibited that the rGO film was biocompatible with Cal-72 cell but against Escherichia coli bacteria. Our work confirmed that rGO film produced by the green reduction method is cytocompatible with mammalian cells, which makes this rGO film a promising material for tissue engineering scaffold or as a surface-modification coating of an implant.
Scalable Synthesis of Ultrathin g-C3N4 Nanosheets with Enhanced Photocatalytic Activities via High Shear Exfoliation
Authors: Yan Ting Nan , Liu En Hui , Chu Zeng Yong , Li Xiao Dong
Published: January 2017

High-shear mixing was demonstrated as an effective approach for the green synthesis of ultrathin g-C3N4 nanosheets with excellent photocatalytic performance. The resultant nanosheets were characterized in terms of morphology, crystal structure, electronic structure and photocatalytic behavior. It was found that the g-C3N4 nanosheets mainly consist of one C-N layer with a thickness about 0.7 nm. The products show a band gap of 2.6 eV and exhibit high photocatalytic activities with almost 4 times higher than their bulk counterparts toward RhB degradation. With the yield as high as 20 %, the present simple route may be qualified as a promising candidate for the mass production of high quality g-C3N4 nanosheets.
Preparation of Superfine Alumina Powders via Hydrothermal Method
Authors: Song Jie Guang , Wang Rui Hua , Wang Xiu Qin , Xu Ming Han , Ma Ming Liang
Published: January 2017

Superfine alumina has various excellent performance, superfine aluminum often used in metallurgy, aerospace, microelectronics and medicine, so the study of alumina has become a hot research at home and abroad, superfine alumina powder the body needs are also increasing. In this paper, superfine alumina powder were prepared by hydrothermal method, and to study the preparation process. The results show that the fibrous alumina particles gradually becomes granular with the increase of pH of the reaction, pH value of 9 to get a uniform particle size distribution and an average size of small powder particles. As the increasing calcination temperature, the alumina particles gradually grow, the homogeneous superfine particulate alumina powders is obtained under calcination temperature at 950¡æ. The better preferred process is that alkali molar ratio of 1:3, a concentration of 0.3mol/L, the reaction temperature at 200°C, calcination temperature of 950°C.
The Investigation of Perovskite LaCo0.6Ni0.4O3-δ as Cathode Interface Contact Material for Intermediate Temperature Solid Oxide Fuel Cells
Authors: Li Zhe , Yan Dong , Zhang Qian , Pu Jian
Published: January 2017

The goal of this study is to identify LaCo0.6Ni0.4O3-δ (LCN) as reliable cathode contact material for intermediate temperature solid oxide fuel cells (SOFC). LCN was prepared through the polymeric steric entrapment precursor route and calcined at 800 °C which shows single perovskite phase. Area specific resistance (ASR) of LCN was measured at 750 °C. The investigation shows that the ASR can be maintained about 50 mΩ·cm2 for 100 hours operation, and presented ASR stability within 10th thermal cycles. The excellent performance of LCN is attributed to good interface adhesion between LCN and interconnect alloy.
Surface Morphology and Phase Transitions of Anodic TiO2 Films Induced by Hydrothermal Exposure
Authors: Chen Zhao Xiang , Ren Li Mei , Yan Yan Hong , Qi Xiao Wen , Yang Yu Lin
Published: January 2017

A dense TiO2 film was fabricated on the titanium surface using the anodization technique. Surface morphology and phase structure of anodic TiO2 film were investigated before and after the hydrothermal exposure at 160 °C for 24 h. The hydrothermal solution was 3.5 wt% NaCl solution and the films were either immersed in NaCl solution or exposed to water vapor during the exposure. It was found that the as-prepared anodic TiO2 film consisted primarily of amorphous oxides and exhibited a relatively smooth surface. After the hydrothermal exposure, lots of rod-like crystals were formed on the solution-immersed film, while aggregated fine nanoparticles emerged on the vapor-exposed one. Thin film X-ray diffraction analysis indicated that the hydrothermal exposure transformed amorphous oxides into crystalline anatase. The corrosion behavior investigation showed that the structural transition of anodic TiO2 film during the exposure reduced the corrosion resistance of anodized titanium greatly.
Effect of Deposition Time on Hardness and Bonding Strength of Magnetron Sputtered TiN Coatings on 316 Stainless Steel
Authors: Zhang Hao , Luo Chen Gang , Duo Shu Wang , Liu Qiang , Wen Ru Chun , Yuan Ming Yang , Wu Yuan Ling
Published: January 2017

TiN coatings were prepared under different deposition time by magnetron sputtering technology. The effects of deposition time on microstructure and properties of TiN coatings were investigated by SEM, EDS, XRD, micro-hardness tester and scratch instrument, respectively. Results showed that coating thickness was gradually increasing with the prolonging of deposition time; The phases were mostly cub-TiN and a small amount of metal hex-Ti and tetr-Ti2N in TiN coatings; Deposition time has a great influence on surface morphology of TiN coatings; The hardness and adhesion of TiN coating both increased firstly and then decreased with the increase of deposition time. In this paper, TiN coating, whose thickness was 4 mm when deposition time was 5 hour, had excellent comprehensive performance, i.e., TiN coating was dense and smooth and its composite hardness was 34.46 GPa and its adhesive force was 16.00 N.
Controlled Preparation and Characterization of Titanium Series Functional Pigment and its Application in Coatings
Authors: Deng Yu , Zheng Jian Xun , Wang Qiang Qiang , Yang Wei Bo , Zhang Song Song
Published: January 2017

In our recent work, we synthesize several spherical rutile TiO2 powders with different average particle size though hydrothermal method using TiCl4 under lower temperature in a shorter reaction period. Afterwards, solar heat-reflection coatings were prepared by using the TiO2 as pigment. The TiO2 powders were characterized by XRD to determine the phase of crystal. The morphology and particle size were observed by using SEM, and the spectral reflectance of the powder samples and coatings were measured using UV/VIS/NIR spectrophotometer. In order to measure the temperature on the back of coatings, the self-assembled equipment which consisted of solar lamps and surface temperature sensors connected to a data logging system was invented. The test results showed that the shape, average particle size and size distribution were closed-packed state and a bigger mean particle size had higher reflectance intensity. Meanwhile, the reflectance was closely connected to the particle size distribution. Actually, the coatings dispersed TiO2 powder with desired size distribution had excellent performance.
Comparison of Mo-10Nb Alloy Target Materials Prepared by Different Techniques
Authors: Gao Jie , Lu You Jun , Hou Jun Feng , Yuan Zhen Xia , Luo Wen , Hu Bai Zhi
Published: January 2017

The Mo powder and Nb powder was used as raw material, the Mo-10Nb alloy target was prepared by different sintering condition (non-pressure sintering and hot pressing sintering). The density, phase composition, microstructure and elemental distribution of Mo-10Nb alloy targets were determined by X-ray diffraction and scanning electron microscopy. The results showed that prepared by hot pressing Mo-10Nb alloy target density of 9.618 g/cm3, grain size 20 ~ 30μm, Mo and Nb element distribution.
Application of Improved BP Neural Network in the Preparation Processing of the CaCO3 Nanocrystalline
Authors: Luo Qiang , Ren Qing Li
Published: January 2017

A three-layer structure back-propagation network model based on the non-linear relationship between the size of the CaCO3 nanocrystalline and the technological factors, such as reaction time, reaction temperature, raw material adding amount of NaCO3 and CaCl2, was established. Moreover, in order to accelerate the converging rate and avoid the non-converging situation, the momentum terms are introduced. Besides, the variable learning speed is adopted. At the same time, the input variables were pretreated by using the main component analysis firstly. And the results show that the improved back propagation neural networks model is very efficient for predication of the CaCO3 nanocrystalline size.
Bentonite-Copolymer Composite for Removing Basic Fuchsin
Authors: He Yu Feng , Li Hong , Zhang Zhen Hua , Lu Ting Jun , Wang Rong Min
Published: January 2017

Basic Fuchsin (BF) is a toxic triphenylmethane dye with molecular formula C20H20ClN3, which is easy to caused serious public health problems. There is a need to develop a cost effective method for its removal from the wastewater containing BF. Here, a novel composite polymer adsorbent, poly (maleic anhydride - acrylic acid - vinyl acetate)/Na-bentonite composite cross-linked with N,N'-methylenebisacrylamide was prepared by in situ copolymerization. The polymer adsorbent (NaB-PMAVM) was characterized and applied to remove BF. It was found that the removal of BF reached to 95.96%. The adsorption isotherms and kinetics were best-fit with the Freundlich isotherm model and the pseudo-second-order kinetic, respectively.
The Preparation of Magnesium Hydroxide Whiskers
Authors: Ren Qing Li , Luo Qiang
Published: January 2017

The magnesium hydroxide whiskers,its length being about 30μm and its diameter being about 3μm, was prepared by hydrothermal conditions. The effect of preparation technology, which includes the reaction temperature and reaction time, was discussed according to the results of XRD, TEM, and SEM. Moreover, the mechanism of the preparation of magnesium hydroxide whiskers was studied.
Microstructural Study on the Low Density SiO2 Soot Body
Authors: Nie Lan Jian , Jia Ya Nan , Wang Lei , Xiang Zai Kui , Liu Fei Xiang , Wang Hui
Published: January 2017

Low density SiO2 soot body, with a certain strength and porosity, is an intermediate of silica glass prepared by the indirect synthetic method. The microstructures of SiO2 soot body have an important influence on the post-sintering process, such as micro-morphologies, pore structures and so on. These microstructures, including micro-morphologies, phase structure, hydroxyl structure, pore structure, pore size distribution and specific surface area, were studied by ESEM, XRD, FTIR, mercury intrusion method and nitrogen adsorption method. Experimental results indicate that, the low density SiO2 soot body is composed of amorphous nano-SiO2 particles with a particle diameter distribution of 100nm ~ 150nm. The pore structure of SiO2 soot body tends to be irregular and the pore shape contains cross-linked holes, through-holes and blind holes. The pore size distribution is wide and involves macropore, mesopore and micropore.
Study of Three-Dimensional Optical Homogeneity of Fused Silica Prepared by Chemical Vapor Deposition
Authors: Shao Zhu Feng , Xiang Zai Kui , Wang Yu Fen , Sui Mei , Bao Yi Wang
Published: January 2017

Optical homogeneity of the fused silica directly affects the wave-front quality of the optical system. Furthermore, three-dimensional optical homogeneity is required in order to produce high-precision prisms, because of its special optical demand. However, the three-dimensional optical homogeneity of fused silica is poor owing to the periodically grow laws based on vertical CVD technical in the process of ingots production. One circular and one square sample were prepared to measuring the three-dimensional optical homogeneity, founding that the vertical direction had worse optical homogeneity result compared to the horizontal direction. The constituents of the sample were tested and analyzed to found the inhomogeneity reason. The method was proposed to improve the three-dimensional optical homogeneity.
The Effect of Concrete Mix Proportion to the Air Bubble Spacing Coefficients of Hardened Concrete
Authors: Wang Yang , Liang Hui Chao , Zhao Bao Cheng , Jiang Yu Chuan
Published: January 2017

A large number of studies have shown that the air content of fresh concrete and the air bubble spacing coefficients of hardened concrete can be used to characterize the frost resistance of concrete. The performance of air-entraining agent is an important influence factor of these two indexes, and the effect of concrete mix proportion cannot be ignored. In this paper, the effect of concrete mix proportion to the air bubble spacing coefficients of hardened concrete has been studied through a series of tests.
Composition Analysis of an Unknown Redispersible Powder
Authors: Ding Jian Jun , Zhao Wen Yan , Guan Hong Yan , Li Xuan , Mei Yi Fei
Published: January 2017

As an important type of additive, the redispersible powder is widely applied in cement-based and gyp-based materials, so as to improve the cementing strength, impermeability, workability, hydrophobicity and so on. However, the chemical composition of the redispersible powders determines its applicability, as well as the degree of improvement to the matrix materials. In this paper, the chemical composition of an unknown redispersible powder was analyzed by several instruments. Firstly, Fourier transform infrared spectroscopy (FTIR) analysis indicated that the polymer was polymerized with monomers of vinyl esters. Secondly, pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) analysis showed the pyrolysis products were mainly acetic acid, methyl acetate and methyl versatates. Considering the pyrolysis mechanism of synthetic polymers and the results from FTIR spectra, the polymer in the redispersible powder was deduced to be the copolymer of vinyl acetate and vinyl ester of versatic acid (VeoVa), which was a monomer with a unique highly branched carbon-rich structure. Thermogravimetry (TG) analysis revealed that the powder contained 74.0% of polymer, 14.5% of calcium carbonate and 11.4% of other inorganic materials.
Ion Chromatography for the Continuous Determination of Sulfite and Sulfide in Gypsum and Gypsum Products
Authors: Xu Dan Hua , Chen Peng , Liu Shi Hua
Published: January 2017

A quantitative ion chromatographic analytical method for the continuous determination of the sulfite and sulfide in gypsum and gypsum products is proposed. This paper established a determination method removal interference with each other between sulfite and sulfide that measure sulfite and sulfide content respectively. A set of calibration graphs for standards with different concentration ranges with indicate a good linear regression.The method presents good repeatability because in all cases the observed RSD was below 1% through two chromatographic parameters both of the retention time and the area of the analytical signal. The accuracy of the method was evaluated through recovery assays. The recoveries varied from93.9% to 105.7% depending on the anion, indicating that the extraction of the analytes was good enough to de used for the determination of the studied anions in gypsum sample.
Toward Integrated Pressure Sensors for Temperatures up to 600°C
Authors: Maralani Ayden , Beker Levent , Pisano Albert P.
Published: January 2017

The main objective of this study is to develop pressure-sensing systems by integrating pressure transducers with the interface circuitry in one package that can withstand harsh environments, particularly high temperatures up to 600°C. To achieve that, both pressure transducer and interface circuitry are individually required to operate and survive up to 600°C with acceptable degrees of reliability. This article reports performance evaluation of fabricated 4H-SiC Junction Field Effect Transistors along with differential pairs for use in the interface circuitry. The test results are very promising and show stable performances from 25°C up to 600°C. Moreover, design, fabrication, and early test (from 25°C up to 100°C) of an SiC-based circular diaphragm-type pressure transducer are also reported.
Phronesis and the epistemological journey through research undertakings involving human participants in the context of Sierra Leone
Authors: Jackson Emerson Abraham
Published: January 2017

This article has provided some philosophical thoughts concerning the journey of research undertakings involving human participants, with consideration given to both natural / physical and human / social science fields, and with a focus on the situation in Sierra Leone (where ‘ethical prudence’ seemed to be lacking for various reasons). In the process of professional engagement, researchers must seek to give serious reflective thoughts on how their engagement may affect participants and communities - this study has unravelled some thoughts on evolving perspectives (technology-mediated engagement and feminist views). Ethical code of practice has been highlighted as an important instrument in helping researchers (particularly in the Sierra Leone context) manifest serious thoughts in their epistemic quest for pursuing knowledge, through engagement with human participants. The ethical requirement of a researcher to demonstrate intellectual virtue / prudence is a key aspect of the discourse in this article - that which enable trust to be established, and more so, the researcher's ability to exercise practical wisdom in their engagement with research communities.Keywords: Phronesis; Epistemology; Ethics; Praxis; Human Participants; Sierra Leone
Understanding the difference between African magic and African science: a conversation with Christian Emedolu
Authors: Uduagwu Chukwueloka S.
Published: January 2017

In the spirit of conversational philosophy endorsed by the Conversational School of Philosophy (CSP), I am oblige not to venerate ideas but to interrogate and scrutinize them in search of loopholes to be filled and weak points that needed to be strengthened in order to achieve what Jonathan Chimakonam calls theoretic sophistication and promote Global Expansion of Thought (GET). To promote GET in African philosophy which has to do with embedding theories and principles with cultural contents like the idea of African science but making them universally applicable, one needs to ride on the wheels of the tools of Conversational philosophy. The primary aim of this short piece is to converse with Christian Emedolu on his article “From Magic to African Experimental Science: Towards a New Paradigm" and interrogate his ideas to assess their theoretic sophisticationKeywords: Emedolu, African Magic, African Science, African Philosophy, GET, Conversationalism
Radiative characteristics of aerosol during extreme fire event over Siberia in summer 2012
Authors: Zhuravleva Tatiana B. , Kabanov Dmitriy M. , Nasrtdinov Ilmir M. , Russkova Tatiana V. , Sakerin Sergey M. , Smirnov Alexander , Holben Brent N.
Published: January 2017

Abstract. Microphysical and optical properties of aerosol were studied during a mega-fire event in summer 2012 over Siberia using ground-based measurements of spectral solar radiation at the AERONET site in Tomsk and satellite observations. The data were analysed using multi-year (2003–2013) measurements of aerosol characteristics under background conditions and for less intense fires, differing in burning biomass type, stage of fire, remoteness from observation site, etc. (ordinary smoke). In June–August 2012, the average aerosol optical depth (AOD, 500 nm) had been 0.95 ± 0.86, about a factor of 6 larger than background values (0.16 ± 0.08), and a factor of 2.5 larger than in ordinary smoke. The AOD values were extremely high on 24–28 July and reached 3–5. A comparison with satellite observations showed that ground-based measurements in the region of Tomsk not only reflect the local AOD features, but are also characteristic for the territory of Western Siberia as a whole. Single scattering albedo (SSA, 440 nm) in this period ranged from 0.91 to 0.99 with an average of ∼ 0.96 in the entire wavelength range of 440–1020 nm. The increase in absorptance of aerosol particles (SSA(440 nm)  =  0.92) and decrease in SSA with wavelength observed in ordinary smoke agree with the data from multi-year observations in analogous situations in the boreal zone of USA and Canada. Volume aerosol size distribution in extreme and ordinary smoke had a bimodal character with significant prevalence of fine-mode particles, but in summer 2012 the mean median radius and the width of the fine-mode distribution somewhat increased. In contrast to data from multi-year observations, in summer 2012 an increase in the volume concentration and median radius of the coarse mode was observed with growing AOD. The calculations of the average radiative effects of smoke and background aerosol are presented. Compared to background conditions and ordinary smoke, under the extreme smoke conditions the cooling effect of aerosol considerably intensifies: direct radiative effects (DRE) at the bottom (BOA) and at the top of the atmosphere (TOA) are −13, −35, and −60 W m−2 and −5, −14, and −35 W m−2 respectively. The maximal values of DRE were observed on 27 July (AOD(500 nm)  =  3.5), when DRE(BOA) reached −150 W m−2, while DRE(TOA) and DRE of the atmosphere were −75 W m−2. During the fire event in summer 2012 the direct radiative effect efficiency varied in range: at the BOA it was −80–−40 W m−2, at the TOA it was −50–−20 W m−2 and in the atmosphere it was −35–−20 W m−2.
Seasonal distribution of short-tailed shearwaters and their prey in the Bering and Chukchi seas
Authors: Nishizawa Bungo , Matsuno Kohei , Labunski Elizabeth A. , Kuletz Kathy J. , Yamaguchi Atsushi , Watanuki Yutaka
Published: January 2017

Abstract. The short-tailed shearwater (Ardenna tenuirostris) is one of the abundant marine top predators in the Pacific; this seabird spends its non-breeding period in the northern North Pacific during May–October and many visit the southern Chukchi Sea in August–September. We examined potential factors affecting this seasonal pattern of distribution by counting short-tailed shearwaters from boats. Their main prey, krill, was sampled by net tows in the southeastern Bering Sea/Aleutian Islands and in the Bering Strait/southern Chukchi Sea. Short-tailed shearwaters were mainly distributed in the southeastern Bering Sea/Aleutian Islands (60 ± 473 birds km−2) in July 2013, and in the Bering Strait/southern Chukchi Sea (19 ± 91 birds km−2) in September 2012. In the Bering Strait/southern Chukchi Sea, krill size was greater in September 2012 (9.6 ± 5.0 mm in total length) than in July 2013 (1.9 ± 1.2 mm). Within the Bering Strait/southern Chukchi Sea in September 2012, short-tailed shearwaters occurred more frequently in cells (50  ×  50 km) where large-sized krill were more abundant. These findings, and information previously collected in other studies, suggest that the seasonal northward movement of short-tailed shearwaters might be associated with the seasonal increase in krill size in the Bering Strait/southern Chukchi Sea. We could not, however, rule out the possibility that large interannual variation in krill abundance might influence the seasonal distribution of shearwaters. This study highlights the importance of krill, which is advected from the Pacific, as an important prey of top predators in the Arctic marine ecosystem.
Geochemical and microstructural characterisation of two species of cool-water bivalves (Fulvia tenuicostata and Soletellina biradiata) from Western Australia
Authors: Roger Liza M. , George Annette D. , Shaw Jeremy , Hart Robert D. , Roberts Malcolm , Becker Thomas , McDonald Bradley J. , Evans Noreen J.
Published: January 2017

Abstract. The shells of two marine bivalve species (Fulvia tenuicostata and Soletellina biradiata), endemic to south Western Australia, have been characterised using a combined crystallographic, spectroscopic and geochemical approach. Both species have been described previously as purely aragonitic, however, this study identified the presence of three phases, namely aragonite, calcite and Mg-calcite using XRD analysis. Data obtained via confocal Raman spectroscopy, electron probe microanalysis, and laser ablation inductively coupled plasma-mass spectrometry (LA ICP-MS) show correlations between Mg/S and Mg/P in F. tenuicostata, and Sr/S and S/Ba in S. biradiata. The composition of organic macromolecules that constitute the shell organic matrix (i.e. soluble phosphorus-dominated and/or insoluble sulphur-dominated fraction) influences the incorporation of Mg, Sr and Ba into the crystal lattice. Ionic substitution, particularly Ca2+ by Mg2+ in calcite in F. tenuicostata, appears to have been promoted by the combination of both S- and P-dominated organic macromolecules. The elemental composition of these two marine bivalve shells is species-specific and is influenced by many factors such as crystallographic structure, organic macromolecule composition and environmental setting. In order to reliably use bivalve shells as proxies for paleoenvironmental reconstructions, both the organic and inorganic crystalline material need to be characterised to account for all influencing factors and accurately describe the "vital effect".
Video cascade accumulation of the total solar eclipse on Svalbard 2015
Authors: Sigernes Fred , Ellingsen Pål Gunnar , Partamies Noora , Syrjäsuo Mikko , Brekke Pål , Eriksen Holmen Silje , Danielsen Arne , Olsen Bernt , Chen Xiangcai , Dyrland Margit , Baddeley Lisa , Lorentzen Dag Arne , Krogtoft Marcus Aleksander , Dragland Torstein , Mortensson Hans , Smistad Lisbeth , Heinselman Craig J. , Habbal Shadia
Published: January 2017

Abstract. This work presents a novel image accumulation filter technique that reveals small-scale features and details from intense luminosity or high dynamic range (HDR) video recordings. It was discovered and developed from the analyses of the Norwegian Broadcasting Corporation (NRK) film of the total solar eclipse that occurred Friday 20 March 2015 in Longyearbyen (78° N, 15° E) on Svalbard, Norway. The result of the filter is fused with a HDR image of the corona and the Solar Dynamic Observatory (SDO) image of the solar disk.
The Brazilian developments on the Regional Atmospheric Modeling System (BRAMS 5.2): an integrated environmental model tuned for tropical areas
Authors: Freitas Saulo R. , Panetta Jairo , Longo Karla M. , Rodrigues Luiz F. , Moreira Demerval S. , Rosário Nilton E. , Silva Dias Pedro L. , Silva Dias Maria A. F. , Souza Enio P. , Freitas Edmilson D. , Longo Marcos , Frassoni Ariane , Fazenda Alvaro L. , Santos e Silva Cláudio M. , Pavani Cláudio A. B. , Eiras Denis , França Daniela A. , Massaru Daniel , Silva Fernanda B. , Santos Fernando C. , Pereira Gabriel , Camponogara Gláuber , Ferrada Gonzalo A. , Campos Velho Haroldo F. , Menezes Isilda , Freire Julliana L. , Alonso Marcelo F. , Gácita Madeleine S. , Zarzur Maurício , Fonseca Rafael M. , Lima Rafael S. , Siqueira Ricardo A. , Braz Rodrigo , Tomita Simone , Oliveira Valter , Martins Leila D.
Published: January 2017

Abstract. We present a new version of the Brazilian developments on the Regional Atmospheric Modeling System (BRAMS), in which different previous versions for weather, chemistry, and carbon cycle were unified in a single integrated modeling system software. This new version also has a new set of state-of-the-art physical parameterizations and greater computational parallel and memory usage efficiency. The description of the main model features includes several examples illustrating the quality of the transport scheme for scalars, radiative fluxes on surface, and model simulation of rainfall systems over South America at different spatial resolutions using a scale aware convective parameterization. Additionally, the simulation of the diurnal cycle of the convection and carbon dioxide concentration over the Amazon Basin, as well as carbon dioxide fluxes from biogenic processes over a large portion of South America, are shown. Atmospheric chemistry examples show the model performance in simulating near-surface carbon monoxide and ozone in the Amazon Basin and the megacity of Rio de Janeiro. For tracer transport and dispersion, the model capabilities to simulate the volcanic ash 3-D redistribution associated with the eruption of a Chilean volcano are demonstrated. The gain of computational efficiency is described in some detail. BRAMS has been applied for research and operational forecasting mainly in South America. Model results from the operational weather forecast of BRAMS on 5 km grid spacing in the Center for Weather Forecasting and Climate Studies, INPE/Brazil, since 2013 are used to quantify the model skill of near-surface variables and rainfall. The scores show the reliability of BRAMS for the tropical and subtropical areas of South America. Requirements for keeping this modeling system competitive regarding both its functionalities and skills are discussed. Finally, we highlight the relevant contribution of this work to building a South American community of model developers.
Sensitivity analysis of the meteorological pre-processor MPP-FMI 3.0 using
algorithmic differentiation
Authors: Backman John , Wood Curtis , Auvinen Mikko , Kangas Leena , Hannuniemi Hanna , Karppien Ari , Kukkonen Jaakko
Published: January 2017

Abstract. The meteorological input parameters for urban and local scale dispersion models can be evaluated by pre-processing meteorological observations, using a boundary-layer parametrization model. This study presents a sensitivity analysis of a meteorological pre-processor model (MPP-FMI) that utilises readily available meteorological data as input. The sensitivity of the pre-processor to meteorological input was analysed using algorithmic differentiation (AD). The AD tool used was TAPENADE. The AD method numerically evaluates the partial derivatives of functions that are implemented in a computer program. In this study, we focus on the evaluation of vertical fluxes in the atmosphere, and in particular on the sensitivity of the predicted inverse Obukhov length and friction velocity on the model input parameters. The study shows that the estimated inverse Obukhov length and friction velocity are most sensitive to wind speed, and second most sensitive to solar irradiation. The dependency on wind speed is most pronounced at low wind speeds. The presented results have implications for improving the meteorological pre-processing models. AD is shown to be an efficient tool for studying the ranges of sensitivities of the predicted parameters on the model input values quantitatively. A wider use of such advanced sensitivity analysis methods could potentially be very useful in analysing and improving the models used in atmospheric sciences.
Significados alrededor del tejido de pelucas oncológicas en mujeres diagnosticadas con cáncer
Authors: Sanabria Juan Pablo , Muriel Andrea Stefanía , Parra Nathalia
Published: January 2017

Fundamento: La pérdida de cabello se constituye como una alteración física que puede influir en la autoestima de mujeres con cáncer. Objetivo: Comprender los significados alrededor del tejido de pelucas oncológicas en mujeres diagnosticadas con cáncer pertenecientes a un grupo de autoayuda en Cali (Colombia).Método: Estudio cualitativo de diseño fenomenológico interpretativo en el que participaron 10 mujeres. Los resultados preliminares se presentaron en dos grupos focales conformados por todas las integrantes del grupo, quienes contribuyeron en el análisis de los resultados recolectados previamente en las 10 entrevistas en profundidad. El análisis de los datos se realizó con el apoyo del programa Atlas.Ti.Resultados: Las participantes describieron la pérdida del cabello como una experiencia traumática de alto impacto emocional. El uso de accesorios les permitió ocultar y reservarse la enfermedad. Las motivaciones para vincularse al grupo se relacionaron con la oportunidad de compartir experiencias con otras pacientes y con el deseo de mejorar tanto su bienestar como el de mujeres con cáncer. Además, pertenecer al grupo les permitió contar con una red de apoyo en la que pudieron expresar sus miedos e inquietudes.Conclusiones: Aunque la caída del cabello no genera implicaciones funcionales para el organismo, se ha identificado que sobre esta parte del cuerpo se inscriben representaciones sociales vinculadas al significado de ser mujer. La actividad de tejido se presenta como un espacio terapéutico en el que las participantes desarrollan estrategias para afrontar aspectos de su vida.
Estudio bibliométrico de la revista psicooncología (2003-2015)
Authors: Morena de Diago Diego , Morena de Diago Beatriz
Published: January 2017

A través de este estudio bibliométrico se pretende mostrar cómo ha sido la trayectoria de la revista en los 12 años de vida con que cuenta. Se muestra cuál ha sido la producción por años, por autor, por tipología de autor (personal y corporativo), por género, por la procedencia geográfica de los autores (países y comunidades autónomas), por afiliación institucional de los mismos, por el número de firmantes de los artículos y, por último, analizar también la temática a través de las palabras clave propuestas por los, autores de los trabajos.
On the Historiography of Africana Philosophy: Overcoming Disciplinary Decadence through the Teleological Suspension of Philosophy
Authors: Headley Clevis
Published: January 2017

This article is a critical philosophical discussion of Lewis Gordon's An Introduction to Africana Philosophy. Gordon in his text does not portray Africana philosophy as an abstract universalism, philosophy as the “view from nowhere” or philosophy as the “god's eye view” on reality. He also refrains from depicting Africana philosophy as a documentary description of Africana identity, thereby indicating a refusal on his part to reduce Africana philosophy to identity politics, to mere psycho-existential babble. Gordon critically engages with race in his text, but his involvement with this concept does not excessively dominate the text. This article critically explores Africana philosophy's involvement with postmodernism, as well as work through Gordon's notions of disciplinary decadence and the teleological suspension of philosophy. The basic analytical thrust endorses Gordon's efforts to represent Africana philosophy as, among other things, an existential phenomenological account of the being-in-the-world of Africana people. This approach represents Africana philosophy as an anti-Cartesian philosophy, precisely because it does not emanate from a theoretically disembodied consciousness nor from an epistemic knowing subject in search of the transcendental foundations of knowledge.
Effects of Macroeconomic Volatility on Stock Prices in Kenya: A Cointegration Evidence from the Nairobi Securities Exchange (NSE)
Authors: Mumo Muinde Patrick
Published: January 2017

This study examined the effects of macroeconomic volatility on stock prices via selected macro variables using the Johansen co-integration methodology. Time series data was obtained from the Kenya National Bureau of Statistics (KNBS) and the Central Bank of Kenya (CBK) for the period 1998-2015. Macro variables studied include inflation, money supply, exchange rates and interest rates against the NSE 20 share index. The study exploits the presence of unit roots of order 1(1) on the data set to apply the Johansen procedure and the Vector Error Correction Model (VECM) for data analysis. The study finds both a long-run equilibrium relationship between stock prices and the macroeconomic variables and between inflation and other macro variables. Specifically, and contrary to earlier evidence on the Kenyan market, the results suggest a negative long-run equilibrium relationship between money supply and stock prices. Inflation shows negative but insignificant relationship. Exchange rates and interest rates show a positive relationship. The short-term dynamics from the VECM support earlier documented evidence, implying the earlier evidence reflect short-run and not long-run dynamics.The study concludes that the effects of inflation seem to outweigh any possible gains from money supply on aggregate firm output in the long-run. Also, the study adduces evidence of possible spurious problems on earlier documented evidence from the reviewed studies that could be attributable to non stochastic processes in the models used. A robustness check using a multivariate approach points to this and confirms the co-integration results.