bluuebunny/crossref_metadata_2025 huggingface dataset:
The Enlightenment on the Construction of Urban Infrastructure in China from Dujiangyan Irrigation Project
Authors: Li Jun Zhuo , Jiang Tao , Ahmad Hassan , Sun Da Jiang , Chen Qi Bing
Published: November 2016

Dujiangyan Irrigation Project promotes the sustainable development of economy and society in Chengdu plain, which plays an important ecological role and has great historical, cultural and social values. As an significant infrastructure, Dujiangyan project not only optimizes the river system distribution in Chengdu plain and improves the ecological living environment of Chengdu plain, but also grants Chengdu plain a rich connotation of water cultures, such as scientific concept of water management, advanced water-control techniques and the customs of loving water and protecting water. These are all the ecological wisdom of ancient urban construction. This essay summarizes the ecological and cultural wisdom of Dujiangyan irrigation project, its influences on the development and living environment of Chengdu plain. It not only provides some pretty enlightenment for rationality and moderation of urban infrastructure construction, also is an important reference of sustainable development. At the same time, this paper puts forward the importance of cultural relics in the process of sustainable development, which provides a new idea about the research on the future urban infrastructure.
Structural Strength Analysis of Ship-to-Shore Crane
Authors: Tang Gang , Hu Xiong , Wang Wei , Tang Tian Hao , Claramunt Christophe , Chen Chuan Wu
Published: November 2016

It is necessary to analyze the strength of STS crane with static load for assessing the safety of the STS crane. A case study of a STS crane with 28 ton capacity and 18 years of working time has been conducted. A testing system with signal sensing, signal conditioning, signal acquiring and signal analyzing has been established. After the field test, all the stresses of the test positions have been calculated and the strength of STS crane with static load is in the allowable range. As a result of this study, a systematic approach to analyze the strength of STS crane with static load is proposed.
Effects of Incubation Temperature, Repeated Application, and Heavy Metal Addition on Degradation of Nitrification Inhibitor 3,4-Dimethylpyrazole Phosphate (DMPP) in Burozem with Model Experiments
Authors: Zhao Mu Qiu , Zhang Li Li , Shi Yun Feng
Published: November 2016

3,4-Dimethylpyrazole phosphate (DMPP) is used to inhibit nitrification when NH4+ or NH4+-producing fertilizers are applied in agricultural and horticultural systems. The kinetics of DMPP decomposition were studied in pretreated and non-pretreated burozems, using model experiments. DMPP was added in same concentration (50 mg·kg-1) but incubated at various temperatures (15, 23 and 30°C). Additionally, DMPP degradation was examined after treatment with Cu2+ or Cd2+ at various doses. When DMPP was applied into the non-pretreated soil, a delay phase of about 9.5-27.4 days appeared in the initial stage of degradation. However, the delay phase disappeared when DMPP was applied into the pretreated soil. The half-life of DMPP in the non-pretreated soil was higher than that of the pretreated soil by about 58-86%. These indicated that an inducible metabolic degradation occurred, following first-order kinetics. The mineralization rate of DMPP was enhanced by increasing temperature, and the half-life decreased significantly with increasing temperature, both in pretreated and non-pretreated soil. With the addition of DMPP and heavy metal (Cu2+ or Cd2+) in the soil, the content of DMPP was different from CK after incubation, and the mineralization of DMPP was significantly decreased with the increase of heavy metal addition. The lower additional amount of Cu2+ (20 mg·kg-1) or Cd2+ (1 mg·kg-1) promoted the degradation of DMPP, while higher additional amount of Cu2+ (500 mg·kg-1) or Cd2+ (25 mg·kg-1) significantly inhibited the decomposition of DMPP.
Integration of Spherical 360° Panoramic Virtual Tour with Assessment Data for Risk Assessment and Maintenance of Tunnel and Cavern
Authors: Usman Fathoni , Banuar Nursimaa , Kurniawan Tri Basuki , Ismail Mohd Nadzari , Othman Nor Azura
Published: November 2016

Construct a tunnel is a challenge to nature. It releases stress by drilling and sometimes blasting different rock formation. Once it is constructed, existence of water seepage infiltrated through weakest formation of rock has developed distresses that become one of common problems in underground structure. This paper presents development a web based distress mapping application using visual assessment, non-destructive assessment and utilizing 360° spherical panoramic images to give real visualization experience tunnel and cavern of underground hydroelectric power plan. In developing the application, the virtual tour engine from krpano and scripting language Java Script were utilized. Statistical analysis on the condition of the distress was also discussed. The developed system is used to improve human experience on the assessment processes at location of distresses. By using this system, the assessment can be recorded into the database easily using any smart device with HTML browser capability and assist safety officer, engineers and tunnel owner to decide appropriate mitigation of maintenance and/or repair in order to prolong service life of the tunnel and caver of the hydroelectric power plan.
AHP Model for Evaluation of Pile Installation Methods
Authors: Kuo Chiang Pin , Chao Li Chung
Published: November 2016

As an economical way of transmitting the loads from structures to the soil or rock layer, pile foundations have been widely applied in construction projects. With an objective of developing a model for selecting the optimum pile installation method for a project, this study investigated three alternative methods that are commonly used in Taiwan. Based on a review of related researches, a generic evaluation framework of a hierarchy comprising 21 factors in four groups is proposed and a model using the analytical hierarchy process (AHP) to produce the weight of the factors and the ratings of the pile installation methods is presented. The model is illustrated using an example, in which the rankings of the alternative methods from best to worst are precast pre-stressed bored piles (PPBP), cast-in-situ concrete piles (CISP) and precast pre-stressed driven piles (PPDP). Practitioners may use the model as a structured, systematic and effective approach in evaluating and selecting the installation method for a project.
Analysis of Unstable Rock-Mass Stability Based on Limit Equilibrium Method and Strength Reduction Method
Authors: Kong Ying , Shi Hua Peng , Yu Hong Ming
Published: November 2016

With the slope unstable rock masses of a stope in Longsi mine, Jiaozuo City, China as the target, we computed and analyzed the stability of unstable rock masses using a limit equilibrium method (LEM) and a discrete element strength reduction method (SRM). Results show that the unstable rock masses are currently stable. Under the external actions of natural weathering, rainfall and earthquake, unstable rock mass 1 was manifested as a shear slip failure mode, and its stability was controlled jointly by bedding-plane and posterior-margin steep inclined joints. In comparison, unstable rock mass 2 was manifested as a tensile-crack toppling failure mode, and its stability was controlled by the perforation of posterior-margin joints. From the results of the 2 methods we find the safety factor determined from SRM is larger, but not significantly, than that from LEM, and SRM can simulate the progressive failure process of unstable rock masses. SRM also provides information about forces and deformation (e.g. stress-strain, and displacement) and more efficiently visualizes the parts at the slope that are susceptible to instability, suggesting SRM can be used as a supplementation of LEM.
Synthesis and In Vitro Characterization of Carbon Nano Tube-Polycaprolactone Composite Scaffold for Odontoblast Cell Interaction
Authors: Ketabi Mohamad Ali , Shahnavazi Maryam , Fekrazad Reza , Tondnevis Farbod , Keshvari Hamid , Raz Majid , Sadeghi Ali , Abolhasani M.M.
Published: November 2016

Dentin tissue engineering is one of innovative and effective regenerative method for treatment of dental pulp and dental tissue, and our research concentrated on preparing an effective scaffold substrate containing carbon Nano tube in polycaprolactone Nano fiber matrix. Our characterization showed benefits of this complex structure and its effect on odontoblast cell interaction. The results indicated that the prepared nanofiber polymer contains 4% CNT have a great potential as biocompatible materials for use in dental tissue engineering and odontoblast cell interaction.
Fabrication of Hydroxyapatite Microcapsules for Controlled Release of Hydrophobic Drug
Authors: Matsunaga Takahiko , Yabutsuka Takeshi , Takai Shigeomi , Yao Takeshi
Published: November 2016

Hydroxyapatite (HAp), a principal component of living bone and teeth, is collecting a lot of attention as a biomaterial owing to its biocompatibility. Also, HAp formed in simulated body fluid (SBF) has flake-like structure and porous body. From these properties, in this study, we fabricated HAp microcapsules encapsulating ibuprofen by attaching the Apatite Nuclei (ANs) on oil droplets containing the ibuprofen and soaking the mixture in SBF. In addition, we evaluated the behavior of drug release from the microcapsules In Vitro.
Osteoblastic Cells Response to Albumin Coatings on Zinc Containing Hydroxyapatite
Authors: Costa Andrea Machado , Mavropoulos Elena , Tanaka Marcelo , Navarro da Rocha Daniel , Mendonça Fonseca Flavia , Prado da Silva Marcelo Henrique
Published: November 2016

In this work, zinc-containing hydroxyapatite (ZnHA) and hydroxyapatite (HA) discs were coated with native bovine serum albumin (BSA) using 100 μg/ml BSA solution at 37°C. Changes on BSA secondary structure from α-helix to β-turn were detected by deconvolution analyses of FTIR amide I band. Fluorescence images of MC3T3-E1 osteoblast cultured on HA and ZnHA discs revealed cells with elongated morphology, typical of 2D experiments, after 24 hours. An intense cytoskeleton organization was observed on samples coated with BSA.
Simultaneous Identification of Amorphous Calcium Phosphate and S.epidermidis Bacteria by Photoacoustic Spectroscopy
Authors: Brangule Agnese , Gross K. , Skadins Ingus , Reinis Aigars , Kroiča Juta
Published: November 2016

The incorporation of biomaterials in human tissue requires methods to study the interface of the implant with the biological setting. We set out to study whether Photoacoustic spectroscopy with a higher level of sensitivity from the cantilever detector could simultaneously detect amorphous calcium phosphate and the bacteria. The calcium phosphate was synthesized, pressed into tablets, and then immersed in a solution containing S.epidermidis bacteria. Spectra were recorded after 1, 2, 3, 4 and 5 days. Deconvolution of the spectra at different time periods was able to separate bands belonging to the bacteria and carbonate bands arising from the calcium phosphate. This allowed the simultaneous identification of the biomaterial and bacteria. It was found that the PAS spectra could not identify the bacterial adhesion process due to the low concentration, but the amide peaks at 3 days inferred colonization of bacteria. This was confirmed by SEM that shoed an increase in the bacteria concentration. This is the first step in showing the simultaneous detection of calcium phosphate and bacteria by Photoacoustic spectroscopy, a method that required more research to show changes on the surface of the implant.
Basic Properties of Novel Bioactive Cement Based on Silica-Calcium Phosphate Composite and Carbonate Apatite
Authors: Zakaria Myrna Nurlatifah , Cahyanto Arief , El-Ghannam Ahmed
Published: November 2016

Silica-calcium phosphate composite (SCPC) and carbonate apatite (CO3Ap) are resorbable bioactive materials with the ability to adapt to bone structure and to induce bone regeneration. Considering the similarity between bone and dental structure, where both are mainly composed of calcium deficient carbonate containing hydroxyapatite, we hypothesize that a SCPC-CO3Ap bone cement might also be favorable for the regeneration of dentin and pulp tissue. Therefore, in the present study we report on the effect of composition and structure of SCPC-CO3Ap cement on the morphology, setting and mechanical properties of the material. The novel bioceramics cement composed of vaterite, dicalcium phosphate anhydrous (DCPA) and SCPC. The powder cement ratio divided into 5 groups: group 1 (60% DCPA : 40% vaterite : 0% SCPC) as a control, group 2 (60% DCPA : 10% vaterite : 30% SCPC), group 3 (60% DCPA : 20% vaterite : 20% SCPC), group 4 (60% DCPA : 30% vaterite : 10% SCPC), and group 5 (60% DCPA : 0% vaterite : 40% SCPC). Each group was mixed by 1M Na2HPO4 aqueous solution at liquid to powder ratio of 0.5 and hardened at 37°C and 100 % of relative humidity for 72 hours. Set cement was examined by X-Ray diffraction (XRD), scanning electron microscopy (SEM) and the mechanical strength was evaluated by diametral tensile strength. XRD patterns revealed that the apatite formation was formed after 72 hours, however the intensity of apatite varied based on the SCPC content. The DTS evaluation indicated that group 3 has the highest mechanical strength compared to others. This was supported by SEM analysis of set cement showing more compact surface microstructure of group 2 and 3 compared to other different ratio and control group. The novel bioceramics cement was successfully made using vaterite, DCPA and SCPC. This new cement is currently being investigated for dental application to induce dentinogenesis.
An Evaluation of Bioactive Glass/Calcium Phosphate Cement Composite, Synthesized via Sol-Gel Method
Authors: Shahrezaee M. , Raz Majid , Sanati M. , Sadeghi Ali , Tondnevis Farbod , Abolhasani M.M. , Moztarzadeh F.
Published: November 2016

In this study four types of calcium phosphate cement/bioactive glass composites has been synthesized via mixing and sol-gel method and the effect of hydroxyapatite/tricalcium phosphate ratio to its mechanical properties and setting time was investigated. The prepared samples were characterized using X-ray diffraction (XRD), foureir transform infra-red spectroscopy (FTIR), scanning electron microscopy (SEM), mechanical testing and setting time measurement. XRD analysis showed amorphous structure of the prepared bioactive glass. But the patterns of the prepared composite had sharp peaks because of their crystalline structure. FTIR analysis indicated that the composites had carbonated calcium phosphate structure. SEM micrographs illustrated amorphous calcium phosphate particles with irregular shapes. With increasing the HA/TCP ratio, Young's modulus and compressive strength of the composites increased from 179 to 453 MPa and from 20 to 38 MPa respectively. The setting time of the samples decreased with increasing the HA/TCP ratio from 22 to 18 minutes.
Controlled Ion Release Property of Glass Ionomer Cement Containing Nanoporous Silica Particles
Authors: Nakanishi Ko , Bando Yosuke , Katsurayama Tomohiko , Morimoto Shino , Abe Shigeaki , Yamagata Shuichi , Yoshida Yasuhiro , Iida Junichiro
Published: November 2016

Controlled ion release property of nanoporous silica particles (NPS) were investigated using cationic fluorescent dye, rhodamine B. The dye was charged into a glass ionomer cements (GIC) pellet containing the particles and then the pellet were immersed into distilled water. The dye-release behavior was observed using a UV-vis. spectrophotometer. GIC containing NPS can release the dye for a couple of weeks, where as other samples released it only a few days. This result suggests that NPS has excellent sustained dye-release property.
Fabrication of Bioactive Cobalt-Chromium Alloys by Incorporation of Apatite Nuclei
Authors: Yabutsuka Takeshi , Mizutani Hiroto , Takai Shigeomi , Yao Takeshi
Published: November 2016

Micrometer-sized pores were formed on the surface of cobalt-chromium (Co-Cr) alloys by sandblasting method. In order to provide bioactivity to the Co-Cr alloys, the alloys were soaked in SBF and heated. By this treatment, amorphous calcium phosphate film was formed on the Co-Cr alloys. Apatite-forming ability of the specimens was evaluated by using SBF.
Adhesion Characterization of Zinc-Substituted Hydroxyapatite Coatings
Authors: Prado da Silva Marcelo Henrique , Navarro da Rocha Daniel , Moura Felipe Nobre , Costa Andrea Machado , Louro Luis Henrique Leme
Published: November 2016

In this study, hydroxyapatite and Zn-containing hydroxyapatite coatings were produced and characterized with respect to adhesion. The coating technique consists of a two-step hydrothermal process. X-ray diffraction (XRD) analyses showed that, in the first step, the coatings consisted of parascholzite (JCPDS-01-086-2372), a mixture of parascholzite and monetite (JCPDS-01-071-1759), or parascholzite and brushite (JCPDS-72-0713), depending on Zn concentration in the precursor solution. The second step consisted of an alkali conversion in a KOH solution. The final coating was identified as pure hydroxyapatite (HA) or Zn-doped hydroxyapatite, depending on the precursor solution Zn content. Scratch tests on the pure HA coatings showed higher adhesion, when compared to Zn-substituted HA coatings.
Bioactivity Assessment of Calcium Phosphate Coatings
Authors: Navarro da Rocha Daniel , de Oliveira Cruz Leila Rosa , Mijares Dindo Q. , Blazutti Marçal Rubens Lincoln Santana , de Campos José Brant , Coelho Paulo G. , Prado da Silva Marcelo Henrique
Published: November 2016

Nowadays, bioactive coatings or modifications on titanium surface have been tested in vitro and in vivo. In this study, two types of calcium phosphate coatings were produced by a chemical deposition method and their bioactivity assay in cell culture medium were investigated. The calcium phosphate coatings were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy with field emission gun (FEG-SEM) analyses. Titanium substrate was successfully coated with brushite using chemical deposition method and, after a second step of conversion, the hydroxyapatite coating was obtained. The hydroxyapatite coating showed a bioactivity property after 14 days’ incubation in McCoy medium culture.
Temperature Influence on the Calcium Phosphate Coatings by Chemical Method
Authors: Navarro da Rocha Daniel , de Oliveira Cruz Leila Rosa , Mijares Dindo Q. , Blazutti Marçal Rubens Lincoln Santana , de Campos José Brant , Coelho Paulo G. , Prado da Silva Marcelo Henrique
Published: November 2016

The increasing interest in the use of brushite and monetite as resorbable calcium phosphate cements or graft materials is related to the fact of these phases being metastable under physiological environment, with higher solubility than hydroxyapatite phase. In this study, X-ray diffraction (XRD) and scanning electron microscopy with field emission gun (FEG-SEM) analyses were performed in order to assess the temperature influence on the production of calcium phosphate coatings by a chemical deposition method. Titanium substrates were successfully coated with brushite and monetite by a chemical deposition method and a brushite-monetite transformation was assessed with the increasing temperature. Brushite deposition was kinetically favored at low temperatures, whereas monetite was the major phase at higher temperatures.
Natural Hydroxyapatite Synthesis from Fish Bones: "Atlantic Bonito" (Sarda sarda)
Authors: Gunduz Oguzhan , Kilic Osman , Ekren Nazmi , Gokce Hasan , Kalkandelen Cevriye , Oktar Faik Nuzhet
Published: November 2016

Hydroxyapatite (HA) is produced from animal sources like bovine-sheep bones and from human sources with different techniques. Nowadays, it is very crucial utilizing higher valued products from waste materials. Especially, fish bones become major sources for HA production. We have used the waste bone of "Atlantic Bonito" (Sarda sarda), which is a very characteristic fish species. It lives through Atlantic Ocean, the Mediterranean Sea and up to the Black Sea, where it is regarded as a point commercial fish. In this study, the fish bones of "Atlantic Bonito" (Sarda sarda) were collected and cleaned from flesh and greasy parts with distilled boiling water. It was washed again with distilled water, dried and calcinated for 4 hours at 850 °C. Afterwards the material was analysed by X-ray diffraction (XRD) and scanning electron microscope (SEM). XRD analysis revealed the obtained bioceramic material is made of 66.7% HA and 33.3% TCP. The fish bone of “Atlantic Bonito” (Sarda sarda) can be easily trandformed to bioceramic material and it can be used in applications where partly resorbable and economic biomaterials with low carbon footprint needed.
Study of Morphological Behavior of Hydroxyapatite, EDTA Hydroxyapatite and Metal Doped EDTA Hydroxyapatite Synthesized by Chemical Co-Precipitation Method via Hydrothermal Route
Authors: Bhattacharjee Birendra Nath , Mishra Vijay Kumar , Rai Shyam Bahadur , Parkash Om , Kumar Devendra
Published: November 2016

Hydroxyapatite Ca10(PO4)6(OH)2: (HAp) with stoichiometric composition and Ca/P (ratio) = 1.67 has attracted much attention in the context of bone transplant due to its similarity with the mineral constituent of mammals bone and teeth. It is frequently used as a filler to replace amputated bone or as a coating to promote bone ingrowth into prosthetic implants. Biomimetics or biomimicry is the imitation of the models, systems, and elements of nature for the purpose of solving complex human problems. Living organisms have evolved well-adapted structures and materials over geological time through natural selection. Biomimetics has given rise to new technologies inspired by biological solutions at macro and nanoscales. Nanostructure modification of dental implants has long been sought as a means to improve osseointegration through enhanced biomimicry of host structures. Several methods have been proposed and demonstrated for creating nanotopographic features.In the present investigation hydroxyapatite and metals (scandium, magnesium and neodymium) doped hydroxyapatite were successfully synthesized in laboratory by chemical precipitation using hydrothermal route and also by taking ethylene diamine tetra-acetic acid as a complexing reagent. The crystal, grain, and bonding structures of resulting HAp were characterized structurally using X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques and spectroscopically using Fourier transform infrared (FT-IR) techniques. From SEM analysis it was found that the irregular structure of HAp changes to nanorods with EDTA HAp which further gets converted to dandelium structure with scandium doping, plate structure with magnesium doping and whiskers structure on doping with neodymium.
Electrospun Poly(ε-Caprolactone)/Bovine Hydroxyapatite (BHA) Composite Nanofibers for Bone Tissue Engineering
Authors: Keler M. Kagan , Daglilar Sibel , Gunduz Oguzhan
Published: November 2016

Tissue engineering applications have opened a different future-promising era for critical injuries, defects and diseases. Bone tissue engineering is the part of tissue engineering which aims to stir up new practical bone re-formation via the interactive combination of biomaterials and cells. Poly (e-caprolactone) (PCL) is a unique semi crystalline polymer material which handles several important features such as biocompatibility, high biomedical durability and degradation properties. Bovine hydroxyapatite (BHA) is another biocompatible material which provides to get ultimate mechanical behavior in composite designs. Because of their high biocompatibility, PCL and BHA were integrated the electrospinning system together. The system was revised for multi-feeding needle equipment. Eight dissimilar tissue scaffolds were produced and investigated for this recent work.
Fabrication of Bioactive Glass Fiber Reinforced Polyamide with High Mechanical Performance by the Function of Apatite Nuclei
Authors: Yabutsuka Takeshi , Fukushima Keito , Kidokoro Yasutaka , Matsunaga Takahiko , Takai Shigeomi , Yao Takeshi
Published: November 2016

We immersed micropores-formed glass fiber reinforced polyamide MXD6 (GFR-MXD6) in SBF and precipitated apatite nuclei in the pores of the substrate by raising both the pH and the temperature of SBF and obtained bioactive GFR-MXD6. By immersing in SBF, hydroxyapatite formation was induced by the apatite nuclei in the pores and grew to the surface of the substrate. High adhesive strength between the formed hydroxyapatite and the substrate was obtained by a mechanical interlocking effect.
Chlorhexidine Adsorption in Hydroxyapatite and Alginate Microspheres by Extrusion in Zinc and Calcium Chloride
Authors: Ayad Nadia Mohammed Elmassalami , Navarro da Rocha Daniel , Costa Andrea Machado , Prado da Silva Marcelo Henrique
Published: November 2016

In this work, the adsorption of a low-concentration solution of chlorhexidine (CHX), an antimicrobial drug, in hydroxyapatite (HA) and alginate microspheres was studied. The microspheres were formed by extrusion of a 1:10 mixture of alginate and HA in two different divalent solutions: CaCl2 and ZnCl2. UV-Vis spectroscopy showed that the microspheres adsorbed approximately half of the chlorhexidine in solution, which was initially at 0.2%. XRD patterns obtained prior adsorption confirmed the presence of HA as the only crystalline phase. Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX) analysis were performed before and after CHX adsorption. The spheres produced in CaCl2 solution did not show significant change after adsorption. However, samples obtained in ZnCl2 solution showed a different microstructure, with the presence of crystals with a high Zn concentration. X-Ray Fluorescence (XRF) confirmed the presence of ZnO in the samples after CHX absorption.
Synthesis and Characterization of CaO-SiO2-MgO Bioactive Glass Produced by Sol-Gel
Authors: Ayad Nadia Mohammed Elmassalami , da Silva Figueiredo Andre Ben-Hur , de Araujo Gonzalez Wilma , Navarro da Rocha Daniel , Blazutti Marçal Rubens Lincoln Santana , Prado da Silva Marcelo Henrique
Published: November 2016

Bioactive glasses have widely used in biomedical applications such as bone filler due to their excellent biocompatibility, bioactivity and osteoconduction characteristics. In this work, a silicate-rich glass was synthesized by the sol-gel method with 60% SiO2 – 30%CaO – 10% MgO composition where fumed silica acts as the silica precursor. This new method was hypothesized to reduce the gel formation time, due to the high surface area of the fumed silica. In addition, this would presumably increase the nanoporosity of the glass. For comparison purposes, we used a glass of the same composition, but with the conventional silica precursor, tetraethyl orthosilicate (TEOS), through the sol gel method. Both were heat treated at 450°C. FT-IR analysis before and after heat treatment at 450°C showed the presence of nitrate groups, especially in the TEOS samples. This is consistent with the more hygroscopic aspect of those samples. The fumed silica samples had significantly less pronounced peaks corresponding to the nitrate groups, consistent with the more porous structure and the less hygroscopic aspect. The fumed silica samples indeed had a lower gelling time and showed similar results obtained by XRD and FT-IR analyses, showing that the use of fumed silica is viable and advantageous in the glass synthesis by the sol-gel process
Optimization of Humid Conditions Using an Ultrasonic Nebulizer for the Fabrication of Hydroxyapatite Film with the Er:YAG Laser Deposition Method
Authors: Yamamoto Ei , Kato Nobuhiro , Hatoko Yuka , Hontsu Shigeki
Published: November 2016

Restoration and maintenance of tooth substance are primary concerns in operative dentistry. Intact tooth is mainly composed of hydroxyapatite (HAp). However, there are no practical HAp materials for the treatment of tooth decay and hypersensitivity. We have newly proposed and developed a tooth restoration technique with intraoral laser ablation using an Er:YAG laser in order to form the HAp thin film on tooth surface in the atmosphere at room temperature. However, the fabricated HAp film is not uniform for the present due to the unsettled water condition at the material surface during the laser ablation. In the present study, we tried to optimize the humid condition using a nebulizer for the fabrication of HAp layer with the Er:YAG laser deposition method. The HAp layers were fabricated on a titanium substrate while changing the flow rate of water mist in order to determine the relationship between the spraying amount and the HAp layer structure. It is revealed that there exists the optimal humid condition to fabricate the uniform hydroxyapatite coating film with the Er:YAG laser deposition method.
Niobophosphate Glass as Sintering Additive for Al2O3-YAG
Authors: de Freitas Cabral Ricardo , Prado da Silva Marcelo Henrique , de Campos José Brant , Raybolt Aline , Lima Jr. Edio Pereira , de Sousa Lima Eduardo
Published: November 2016

In this study, the following compositions were produced: Al2O3-YAG laser with 2, 4, 6 and 15% by weight of niobophosphate glass (30mol%P2O5-30mol%Nb2O5-20mol%CaO-20mol%CaF2). Sintered discs were characterized by scanning electron microscopy (SEM), X-Ray diffraction (XRD) with the refinement by the Rietveld method and density. The YAG-Al2O3 composite sintered at 1450 °C showed densification of 90%, which indicates the effectiveness of the sintering additive.
Synthesis and Characterization of MgPSZ-PMMA Composite by Sol-Gel Modification and Direct Foaming Technique Using Egg Whites
Authors: Takarini Veni , Rudyawan Alfend , Hardiansyah Andri , Septawendar Rifki , Prastomo Niki , Hasratiningsih Zulia , Djustiana Nina , Purwasasmita Bambang Sunendar
Published: November 2016

This study prepared Magnesium-Partially Stabilized Zirconia (Mg-PSZ) filler synthesis and direct foaming technique using egg whites, and impregnated by PMMA. The results were evaluated systematically by X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and Transmission Electron Microscope (TEM). XRD results denote that the powder sample of MgPSZ was successfully formed with various crystal size of tetragonal and monoclinic phase. SEM and TEM observations revealed that nanoparticles MgPSZ were in spherical and long rounded shapes. Furthermore, SEM observation revealed that the direct foaming method were also successful in the formation of porous structures which favourable for impregnation process by PMMA. The use of egg whites as a polymer precursor in both methods demonstrates that porous specimens contained nanosized, predominantly tetragonal, Mg-PSZ powders were successfully synthesized. This shall yield an interesting prospect towards cheap, reliable, and biocompatible product to resemble the modulus elasticity of dentin.
VSC Sorption onto Mg-Fe-F Layered Double Hydroxide and its Fluoride Release in Aqueous Solution
Authors: Yokogawa Yoshiyuki , Namba Shota , Kinoshita Junichiro , Morita Yuki , Fujii Kazuo , Hotta Masato , Doi Yutaka
Published: November 2016

Etiology of halitosis is often concerned with gram-negative anaerobic bacteria, which produce the malodorous compounds such as volatile sulfur compounds (VSC), hydrogen sulfide and methyl mercaptan. The absorbents for the malodorous compounds are expected to prevent the teeth from decaying and peiodontics disease. The VSC adsorption capabilities of layered double hydroxides, of which composition is A1-xBx(OH)2Cx/n·mH2O, where A and B are Mg and Fe ions, and C are carbonate (CO32- : MgFe LDH CO3) and fluorine (F - : MgFe LDH F) ions in aqueous medium was studied by GC/FPD. The concentration of H2S rapidly decreased for first 1 hours of soaking in H2S water and fell to 0% in 4-5 h when MgFe LDH CO3 was applied. MgFe LDH F was used, then the H2S concentration was quickly decreased the same as MgFe LDH CO3, and 8 mg/l of fluorine was released at a time. The iron ion was not detected in the H2S water after soaking for 18 hours. The MgFe LDHF are expected to be likely adsorbent for the fast removal of VSC from the mouth and fluorine releasing agent.
Stability Assessment of 85 Sandblasted and Laser-Etched Surface Zirconia Implant Using the Periotest Method over 4 Months of Bone Integration Time
Authors: Noumbissi Sammy , Piconi Corrado
Published: November 2016

The stability of a series of 85 one-piece zirconia implants performed by the same surgeon between 2011 and 2015 has been analyzed retrospectively. The stability was measured using the Periotest device during 4 months of osseointegration. The implants had two type of endosseous surfaces: fully sandblasted and laser etched at the crest of the threads. Stability values were assessed starting at the time of placement, two, four, eight, 12 and 16 weeks. The pattern and timing of osseointegration and implant stability resulted in observations similar to that observed with sandblasted and coated titanium implants. As a result of laser etching, the implants displayed higher roughness with a bone like surface topography and appear to have faster osseointegration and higher values of stability in comparison with sandblasted implants.
In Vitro Evaluation of Biomimetic Incorporation and Release Kinetics of BMP2 on Functionalized Bio-Oss® Block
Authors: Teng Fei , Liu Yue Lian
Published: November 2016

Objective: To functionalize the Bio-Oss® Block with biomimetic coating incorporating BMP2 and evaluate the release kinetics of the incorporated BMP2 In Vitro.Materials and methods: Bio-Oss® Blocks were prepared with the size of 7mm x 10mm x 4mm. Each block was immersed and suspended in 300ml 5-fold-concentrated modified Tyrode solution for 24 hours to form a seeding substratum. BMP2 at the concentration of 10ug/ml was added into 120ml supersaturated calcium phosphate solution and co-precipitated within the growing layer for 48 hours. The loading amount of incorporated BMP2 was determined using enzyme-linked immunosorbent assay . The surface characterization of the coating was evaluated by scanning electron microscopy. The distribution of coating-incorporated protein was mapped by a confocal laser-scanning microscope. BMP2 release profiles from the functionalized blocks under different circumstances were monitored. Results: The total loading of BMP2 in a BMP2-incorporated-block is 50.35 ± 6.41μg. The crystalline coating layer deposited on both the superficial surfaces and internal surfaces of the blocks. The BMP2 was distributed homogeneously in the whole block. The coating-incorporated depot of BMP2 barely released in Tris-HCl buffered solution (pH of 7.4). However, when the functionalized blocks were immersed in Citric acid-Sodium citrate buffered solution (pH of 5), or were co-cultured with osteoclasts, the coating-incorporated BMP2 depot showed a sustained release.Conclusions: BMP2 were successfully incorporated onto and into the Bio-Oss® Blocks. A sustained delivery of a lower concentration of BMP2 (μg-BMP2) from Bio-Oss® Block was achieved in acidic solution or with the mediation of osteoclasts.
The HL-60 Cells Response to Various Particle Sizes of Tetracalcium Phosphate Ceramic Delivery System
Authors: Benghuzzi Hamed , Tucci Michelle
Published: November 2016

The specific objective of this investigation is to study the effect of tetracalcium phosphate (TeCP) delivery system fabricated from three different particle sizes (<38, 45 and 75 um) on the viability of HL-60 cell line in culture. Each TeCP reservoir was fabricated using standard protocols. The sintered microcrystal material were cold pressed at 5000 kg compression load, sterilized and loaded into wells pre-plated with 106 HL-60 cells. At the end of 24, 48, and 72 hours, the supernatants (cell suspension) from the wells were collected for cell count (a hemacytometer method) and lactate dehydrogenase (LDH) assays. The cells were evaluated for structural cellular damage by using conventional histopathological protocols (H&E stain). Results obtained from this investigation suggest the followings: (i) particle sizes are key elements in developing TeCP delivery system, (ii) the use of <38 um particle sizes would be favorable for long duration of delivering biologicals from the TeCP reservoirs due to the viability of HL-60 cells, (iii) LDH activities were directly proportional the particle sizes of the ceramic capsules compared to the control and (iv) there were less cellular structural changes in devices fabricated from <38 um particle sizes and the cells became more reactive with an increase in particle sizes.
Colloidal Apatite Nanoparticles: Insights on their Interaction with Cells and Artificial Lipid Membranes
Authors: Drouet Christophe , Fleury Jean Baptiste , Stefanic Martin , Choimet Maela , Al-Kattan Ahmed , Kim Hyoung Mi , Oh Jae Min , Tourrette Audrey , Santran Veronique , Pipy Bernard , Ward Kevin
Published: November 2016

Biomimetic nanocrystalline apatites are analogous to bone mineral. They can be exploited not only for bone regeneration applications, but it is also possible to take advantage of their biomimetic features to explore novel domains of research such as in nanomedicine, if the nanoparticles are stabilized as a colloidal formulation. In this contribution, we concentrate on AEP/HMP-stabilized colloidal apatite nanoparticles (NPs) and on their interaction with different types of cells so as to get experimental evidence on their low cytotoxicity, non-proinflammatory potential, and good compatibility with Red Blood Cells. We then started to explore their interaction with an artificial free-standing phospholipid bilayer, as a simplified model for cell membranes: results indicate, for the first time, that these colloidal apatite NPs can modulate phospholipid bilayer membrane properties, and may even favor the permeation of small molecules (illustrated here with luminescent FITC), which could ultimately be exploited for nanomedicine applications in view of enhancing intracellular drug delivery.
Electrospun Polyvinylpyrrolidone (PVP) Nanofiber Mats Loaded by Garcinia mangostana L. Extracts
Authors: Sriyanti Ida , Edikresnha Dhewa , Munir Muhammad Miftahul , Rachmawati Heni , Khairurrijal
Published: November 2016

Composite nanofibers of polyvinylpyrrolidone (PVP) and Garcinia mangostana L. extract (GME) have been synthesized through electrospinning method for application in drug delivery systems. The precursor solution of 10 mL PVP 10% w/w and GME 2% w/w was then electrospun collected at the rotating collector at the following optimum parameters: a voltage of 15 kV, a collector-nozzle distance of 12 cm, and a flow rate of 1 mL/hour. SEM images showed that the average diameters were 476 nm and 690 nm for the PVP and PVP-GME composite nanofibers, respectively. To some degree, the addition of GME into PVP nanofibers increased the average diameter size of nanofibers. Moreover, the release studies, it was shown that 80% of the GME was released within 30 minutes. Therefore, the PVP-GME composite nanofibers can be applied as the drug delivery systems.
Corrosion Inhibition of 6063 Aluminum Alloy in 0.5 M Sodium Hydroxide Medium by Aqueous Extract of Seeds of Garcinia indica
Authors: Prabhu Deepa , Padmalatha
Published: November 2016

The corrosion inhibition of Garciniaindica extract (GIE) on 6063 aluminum alloy was investigated in 0.5 M sodium hydroxide (NaOH) solution by weight loss method and Tafel polarization techniques. The effects of inhibitor concentrations, temperature on the inhibitor action were investigated. Inhibition efficiency was found to increase with increase in concentration of inhibitor and it increased with increase in the temperature. The kinetic parameters and thermodynamic parameters were calculated. The adsorption of GIE was found to be through chemisorption and obeyed Langmuir adsorption isotherm.
Experimental Analysis of Thermal Fatigue in Bimetallic Welds
Authors: Aggarwal Hamender Kumar , Chhibber Rahul , Arora Navneet , Mehta Rajeev
Published: November 2016

The bimetallic weld joints are widely utilized in the pressurized water reactors, boiling water reactors, heat exchangers in process industries, heat transport piping system utilized in nuclear plants, etc. The present study is aimed at analyzing the bimetallic weld strength degradation due to thermal fatigue. For generating thermal fatigue like conditions, an experimental test rig has been developed. The bimetallic weld between low alloy steel SA 516 grade 70 and stainless steel 304 L was prepared. The experimental results show that, heating time, notch radius and number of cycles have the effect on tensile properties of bimetallic welds.
Application of Neural Network for the Prediction of Tensile Properties of Friction Stir Welded Composites
Authors: Shettigar Arun Kumar , Prabhu Subramanya , Malghan Rashmi , Rao Shrikantha , Herbert Mervin
Published: November 2016

In this paper, an attempt has been made to apply the neural network (NN) techniques to predict the mechanical properties of friction stir welded composite materials. Nowadays, friction stri welding of composites are predominatally used in aerospace, automobile and shipbuilding applications. The welding process parameters like rotational speed, welding speed, tool pin profile and type of material play a foremost role in determining the weld strength of the base material. An error back propagation algorithm based model is developed to map the input and output relation of friction stir welded composite material. The proposed model is able to predict the joint strength with minimum error.
Influence of Spheroidizing Heat Treatment on Mechanical Properties of EN47 Steel
Authors: Harisha S.R. , Sharma Sathya Shankar , Kini U. Achutha
Published: November 2016

The high temperature phase austenite in steel has the property to transform into a variety of room temperature phases like coarse pearlite, bainite & martensite depending upon the cooling cycle. The machinability and toughness depend upon the shape and distribution of pro eutectoid harder phases. The spherical or oval shapes give lesser resistance for machining process. So it is required to design the heat treatment to tailor the property as required by the application. In this view, it is proposed to study the mechanical and micro structural properties of EN47 steel undergoing Spheroidization. The aim of this work is to test the hardness, toughness and wear property of the steel in spheroidised condition. Hardening treatment improves hardness of the material, a marginal decrease in hardness value with improved ductility is observed in tempering. Hardening and longer duration tempering show better wear resistance compared to other heat treatments. Both mild and severe wear regions are observed. Generally mild wear region is observed above five hours of continuous running of the specimen. Micro structural analysis shows the existence of pearlitic structure in as bought & normalized specimen, lath martensitic structure in hardened specimen.
Enhanced Catalytic Activity of α-Fe2O3 with the Adsorption of Gases for Ammonia Synthesis
Authors: Qureshi Saima , Yahya Noorhana , Kait Chong Fai , Alqasem Bilal , ur Rehman Zia , Irfan Muhammad
Published: November 2016

Ab initio density functional theory employed to study the adsorption of hydrogen and nitrogen gas molecule on the α-Fe2O3 (111) surface for ammonia synthesis. The calculated adsorption energy is-4.70kcal/mol, -4.60kcal/mol,-4.38kcal/mol and-3.77kcal/mol for different orientations of adsorbed gas molecules and shows that system is stable and gas molecules have adsorbed. It can also be seen with adsorption of gas molecules the net spin of hematite enhanced from 0 to 2 hence confirms the activity of hematite surface. Hematite nanowires synthesized by oxidation method. Raman spectrum analyses demonstrates that the nanowires are single-crystalline. Field Emission Scanning Electron Microscopy (FESEM) reveals that the nanowires have lengths of 10-25 μm. The magnetic saturation of the nanowires is 15.6 emu/g investigated by vibrating sample magnetometer (VSM). Ammonia was synthesized by magnetic induction method using the hematite nanowires as catlyst and quantified by Kjeldahl method. It is found that the role of gases adsorption was able to enhance catalytic activity of hematite nanowires for the ammonia synthesis. This green synthesis method could be a contender to the Haber-Bosch process currently used by the industry.
Hydrogen Assisted Tempered Martensite Embrittlement of Ultra High Strength Martensitic Steel
Authors: Chen T.C. , Chien Wen Hao , Wang Yuan Tsung , Huang Ching Yuan , Yen Hung Wei , Lin Hsin Chih
Published: November 2016

The demand for new materials that provide excellent structural performance while reducing weight and being cost-effectively manufactured is increasing. For applications with high strength requirements, ultra-high strength steels (UHSS) have been widely used. However, with such a high strength level, UHSS are very sensitive to the hydrogen that could be ease by the tempering process. In this research, the correlation of hydrogen and tempering process on commercial UHSS 15B30 has been studied. Results show that the tensile strength (TS) of as-quenched 15B30 is about 1900MPa. After tempering treatment of the quenched 15B30, the TS decreases from 1600MPa to 1200MPa with tempering temperature increased from 200°C to 400°C. The 15B30 specimens, being subjected to hydrogen charge, exhibit the dramatic reduction of mechanical strengths.
A Synthesize Protocol for Graphene Nanosheets
Authors: Yao Yu Qin , Cen Yin Jie , Sisson Richard D. , Liang Jian Yu
Published: November 2016

Chemical synthesis is cheap and easy to be tailored. Reduction of graphite oxide to form graphene nanosheets is a necessary step that determines yield, quality, chemical and surface properties of graphene nanosheets. In this report, the reduction of graphite oxides by chemical and thermal methods has been employed to convert graphite oxide synthesized by the same wet chemical method using KMnO4 and H2O2. The characterization results from the two reduction methods indicate that a combination of wet oxidation of graphite and thermal reduction method is an efficient and environmental friendly way to produce graphene.
Analysis of Mechanical Behaviour of Heat Affected Zone on Ferritic Side of Bimetallic Welds under Thermal Fatigue Conditions
Authors: Aggarwal Hamender Kumar , Chhibber Rahul , Arora Navneet , Mehta Rajeev
Published: November 2016

In this paper the effect of thermal fatigue on mechanical behaviour of the heat affected zone on ferritic side of bimetallic weld was investigated. The bimetallic weld coupons between ferritic steel SA516 Grade 70 and stainless steel 304L were fabricated using TIG (Tungsten Inert Gas) welding process. In this investigation, an experimental test rig was developed and used to simulate the thermal fatigue conditions at laboratory scale. The thermal fatigue factors selected were heating time, notch radius and number of cycles.
Tensile Properties of Ground Coffee Waste Reinforced Polyethylene Composite
Authors: Tan Ming Yee , Kuan Hoo Tien Nicholas , Khan Amir Azam
Published: November 2016

This paper presents composite of oxo-biodegradable high density polyethylene (oxo-HDPE) and ground coffee waste (GCW). The blends were evaluated at the proportion of 94.5 to 5.5 polymer-filler ratio with different particle sizes, extraction and mercerisation treatments. Compression moulding has been employed to fabricate the composite. Microstructure of the ground coffee waste was characterised using SEM. SEM showed the surface of the treated fibres were coarser as impurities were removed. Chemical modificated GCW showed better adhesion with the matrix. Both untreated and treated GCW/oxo-HDPE composite improved in tensile modulus.