bluuebunny/crossref_metadata_2025 huggingface dataset:
Remote Sensing Observation of Particulate Organic Carbon in the Pearl River Estuary
Authors: Liu Dong , Pan Delu , Bai Yan , He Xianqiang , Wang Difeng , Wei Ji-An , Zhang Lin
Published: July 2015

River estuaries are connectors of terrestrial and marine ecosystems. Riverine particulate organic carbon (POC) is discharged into oceans after a series of biogeochemical reactions in estuaries. Satellite monitoring of POC will improve our understanding of the carbon dynamics of these water bodies. Based on in situ data from four seasonal survey cruises, we developed an algorithm for estimating POC concentrations in the Pearl River Estuary (PRE). Reflectance ratios, Rrs(678)/Rrs(488) and Rrs(748)/Rrs(412), were set as inputs to calculate POC concentration in the PRE. The algorithm was then applied to MODIS/AQUA data to inverse POC concentrations in the PRE from 2002 to 2014. Additionally, sources, impact factors, and seasonal distributions of POC were also investigated. Phytoplankton contributed more to POC in off-shore waters than that in in-shore waters in autumn and spring, but showed the opposite pattern in winter. Under the influence of freshwater from the Pearl River, underwater topography, tides, winds, etc., the seasonal POC concentrations along a specific section, vertical to water depth gradient, decreased in different seasons. These decreases could be described by exponential functions (y = aebx, b < 0). The distribution of POC concentrations in the PRE resulted from complex physical and biogeochemical processes, which can change spatially and seasonally.
Detecting Change Dates from Dense Satellite Time Series Using a Sub-Annual Change Detection Algorithm
Authors: Cai Shanshan , Liu Desheng
Published: July 2015

Multi-temporal satellite images are available at very high revisit frequency, allowing the characterization of land-cover transitions and trajectories in greater detail. However, most change detection methods aim to capture a snapshot of land cover, for instance on an annual scale, which do not describe changes that occurred between the annual time points. In this study, we present a sub-annual change detection (SCD) approach to detect change dates from dense satellite time series. SCD estimates change dates by analyzing differences between two consecutive annual segments in two steps. To validate the proposed method, SCD was applied to real and simulated time series of MODIS 16-day NDVI from 2000 to 2012 for MODIS tile h11v05 and a sub-area in southeast Ohio, USA. The results show that SCD can successfully detect from dense time series the dates of changes representing land-cover transitions among various vegetated land covers. In addition, SCD can achieve comparable accuracy on the date of abrupt land-cover changes for the real time series tested in the study area when compared with the trend and seasonal changes identified by a Breaks for Additive Seasonal and Trend (BFAST) method. Future effort will be given to apply the proposed approach to various remotely sensed time series for other areas with extreme climates.
Application of Visible and Near-Infrared Hyperspectral Imaging to Determine Soluble Protein Content in Oilseed Rape Leaves
Authors: Zhang Chu , Liu Fei , Kong Wenwen , He Yong
Published: July 2015

Visible and near-infrared hyperspectral imaging covering spectral range of 380–1030 nm as a rapid and non-destructive method was applied to estimate the soluble protein content of oilseed rape leaves. Average spectrum (500–900 nm) of the region of interest (ROI) of each sample was extracted, and four samples out of 128 samples were defined as outliers by Monte Carlo-partial least squares (MCPLS). Partial least squares (PLS) model using full spectra obtained dependable performance with the correlation coefficient (rp) of 0.9441, root mean square error of prediction (RMSEP) of 0.1658 mg/g and residual prediction deviation (RPD) of 2.98. The weighted regression coefficient (Bw), successive projections algorithm (SPA) and genetic algorithm-partial least squares (GAPLS) selected 18, 15, and 16 sensitive wavelengths, respectively. SPA-PLS model obtained the best performance with rp of 0.9554, RMSEP of 0.1538 mg/g and RPD of 3.25. Distribution of protein content within the rape leaves were visualized and mapped on the basis of the SPA-PLS model. The overall results indicated that hyperspectral imaging could be used to determine and visualize the soluble protein content of rape leaves.
Electrochemical Co-Reduction Synthesis of AuPt Bimetallic Nanoparticles-Graphene Nanocomposites for Selective Detection of Dopamine in the Presence of Ascorbic Acid and Uric Acid
Authors: Zhao Zongya , Zhang Mingming , Chen Xiang , Li Youjun , Wang Jue
Published: July 2015

In this paper, AuPt bimetallic nanoparticles-graphene nanocomposites were obtained by electrochemical co-reduction of graphene oxide (GO), HAuCl4 and H2PtCl6. The as-prepared AuPt bimetallic nanoparticles-graphene nanocomposites were characterized by scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and other electrochemical methods. The morphology and composition of the nanocomposite could be easily controlled by adjusting the HAuCl4/H2PtCl6 concentration ratio. The electrochemical experiments showed that when the concentration ratio of HAuCl4/H2PtCl6 was 1:1, the obtained AuPt bimetallic nanoparticles-graphene nanocomposite (denoted as Au1Pt1NPs-GR) possessed the highest electrocatalytic activity toward dopamine (DA). As such, Au1Pt1NPs-GR nanocomposites were used to detect DA in the presence of ascorbic acid (AA) and uric acid (UA) using the differential pulse voltammetry (DPV) technique and on the modified electrode, there were three separate DPV oxidation peaks with the peak potential separations of 177 mV, 130 mV and 307 mV for DA and AA, DA and UA, AA and UA, respectively. The linear range of the constructed DA sensor was from 1.6 μM to 39.7 μM with a detection limit of 0.1 μM (S/N = 3). The obtained DA sensor with good stability, high reproducibility and excellent selectivity made it possible to detect DA in human urine samples.
Fuel Consumption and Vehicle Emission Models for Evaluating Environmental Impacts of the ETC System
Authors: Weng Jiancheng , Wang Ru , Wang Mengjia , Rong Jian
Published: July 2015

The environmental outcome of the Electronic Toll Collection (ETC) system is an important aspect in evaluating the impacts of the ETC system, which is influenced by various factors including the vehicle type, travel speed, traffic volume, and average queue length of Manual Toll Collection (MTC) lanes. The primary objective of this paper is to develop a field data-based practical model for evaluating the effects of ETC system on the fuel efficiency and vehicle emission. First, laboratory experiments of seven types of vehicles under various scenarios for toll collection were conducted based on the Vehicle Emissions Testing System (VETS). The indicator calculation models were then established to estimate the comprehensive benefit of ETC system by comparing the test results of MTC lane and ETC lane. Finally, taking Beijing as a case study, the paper calibrated the model parameters, and estimated the monetization value of environmental benefit of the ETC system in terms of vehicle emissions reduction and fuel consumption decrease. The results shows that the applications of ETC system are expected to save fuel consumption of 4.1 million liters and reduce pollution emissions by 730.89 tons in 2013 in Beijing.
Awareness Workshop as an Effective Tool and Approach for Education in Disaster Risk Reduction: A Case Study from Tamil Nadu, India
Authors: Asharose  , Saizen Izuru , Sasi Praveen
Published: July 2015

The core of empowering a community to become more resilient is rooted in disaster risk reduction and its education imparted using various educational tools, mainly through awareness and training programs. Conveying the available knowledge resources to the community by transforming it in a way that matches the local context in order to build a “culture of safety” is the hardest matter to be dealt with. It becomes the responsibility of the disaster management experts, concerned authorities, and researchers to focus more on disaster education by making the resources available to vulnerable communities. Taking this into account, this paper discusses an educational tool prepared for conducting awareness workshops. The paper particularly focuses on the educational tool application in the study area to illustrate its use in “real world” circumstances and to test its efficiency and limitations. It was found that such workshops can bring about a positive change in the level of understanding about disasters and the significance of disaster risk reduction measures. At the same time, it emphasizes that awareness generation is not a short-term affair. The sustainability of educational projects and programs is essential in inculcating disaster risk reduction as a part of people’s life and culture.
Learning from Ebola Virus: How to Prevent Future Epidemics
Authors: Kekulé Alexander
Published: July 2015

The recent Ebola virus disease (EVD) epidemic in Guinea, Liberia and Sierra Leone demonstrated that the World Health Organization (WHO) is incapable to control outbreaks of infectious diseases in less developed regions of the world. This essay analyses the causes for the failure of the international response and proposes four measures to improve resilience, early detection and response to future outbreaks of infectious diseases.
The Apis mellifera Filamentous Virus Genome
Authors: Gauthier Laurent , Cornman Scott , Hartmann Ulrike , Cousserans François , Evans Jay , De Miranda Joachim , Neumann Peter
Published: July 2015

A complete reference genome of the Apis mellifera Filamentous virus (AmFV) was determined using Illumina Hiseq sequencing. The AmFV genome is a double stranded DNA molecule of approximately 498,500 nucleotides with a GC content of 50.8%. It encompasses 247 non-overlapping open reading frames (ORFs), equally distributed on both strands, which cover 65% of the genome. While most of the ORFs lacked threshold sequence alignments to reference protein databases, twenty-eight were found to display significant homologies with proteins present in other large double stranded DNA viruses. Remarkably, 13 ORFs had strong similarity with typical baculovirus domains such as PIFs (per os infectivity factor genes: pif-1, pif-2, pif-3 and p74) and BRO (Baculovirus Repeated Open Reading Frame). The putative AmFV DNA polymerase is of type B, but is only distantly related to those of the baculoviruses. The ORFs encoding proteins involved in nucleotide metabolism had the highest percent identity to viral proteins in GenBank. Other notable features include the presence of several collagen-like, chitin-binding, kinesin and pacifastin domains. Due to the large size of the AmFV genome and the inconsistent affiliation with other large double stranded DNA virus families infecting invertebrates, AmFV may belong to a new virus family.
Nouvelles sépultures sur le territoire de la «nécropole royale» de Gonur Dépé
Authors: Sarianidi Viktor Ivanovič , Dubova Nadezhda A.
Published: July 2015

Cet article présente la découverte récente (2009) d’une sépulture non pillée sur le site de Gonur Dépé au Turkménistan (tombe no 3900). Datée 2400-2200 avant J.-C., cette tombe se rattache à la période ancienne de la « Nécropole royale » du site. Les parois de la chambre funéraire sont ornées de mosaïques décoratives. Le mobilier mis au jour comporte des récipients en céramique et en bronze, parmi lesquels un grand chaudron, ainsi que des objets en pierre et, notamment, un grand bâton. La découverte la plus remarquable est un char en bois à quatre roues tiré par deux chameaux, dont les roues sont assorties de jantes en cuivre ou en bronze. Sept squelettes humains et les restes de deux gros chiens ont été découverts. Les auteurs commentent le rituel funéraire et symbolique en relation avec le zoroastrisme. Une autre tombe riche voisine (no 3880) appartient également à la catégorie des « tombes royales ». Des squelettes de chiens et de chameaux étaient associés aux inhumations et divers objets funéraires et éléments de décor architectural ont été mis au jour. Les relations « internationales » dont témoigne le mobilier de ces tombes avec les civilisations indienne et mésopotamienne sont commentées sur la base des formes de bronze et de l’iconographie (symbole de la montagne) ; l’image d’un combat entre dragons et serpents fait l’objet d’un commentaire particulier.
Pragmatics and Social Deixis: Reclaiming the Notion of Conventional Implicature
Authors: Levinson Stephen C.
Published: July 2015

Proceedings of the Fifth Annual Meeting of the Berkeley Linguistics Society (1979), pp. 206-223
Working 1s and Inversion in Italian, Japanese, and Quechua
Authors: Perlmutter David M.
Published: July 2015

Proceedings of the Fifth Annual Meeting of the Berkeley Linguistics Society (1979), pp. 277-324
CONTRACTUAL OBLIGATIONS ANALYSIS FOR CONSTRUCTION WASTE MANAGEMENT IN CANADA
Authors: Mendis Daylath , Hewage Kasun N. , Wrzesniewski Joanna
Published: July 2015

Construction industry creates a massive amount of waste, which typically ends up in landfills. Canadian construction industry represents 30% of the total municipal solid waste deposited in landfills. Construction and demolition (C&D) waste has created negative socioeconomic and environmental impacts including contaminating ground water, emitting greenhouse gases, and adding more waste to scarce landfills. Literature is cited rework/waste generation due to ambiguity/errors in construction contract documents. Exculpatory clauses in contract documents are included in contractual agreements to prevent contractor claims, which often cause rework. After an extensive contract documents review, these clauses were categorized in to eight major areas. This paper (1) analyses expert opinions on pre-identified contractual clauses; and (2) introduces recommendations to minimize rework and waste in construction projects. It was found that the clauses related to quality, workmanship, and field quality control/inspection have the most potential to generate construction waste.
APPLICATION OF AN ELASTOPLASTIC MODEL TO PREDICT BEHAVIORS OF CONCRETE-FACED ROCK-FILL DAM UNDER COMPLEX LOADING CONDITIONS
Authors: Wei Kuangmin , Zhu Sheng
Published: July 2015

In this research, a simplified rotational kinematic hardening model with the concept of sub-loading was used to predict behaviors of Concrete-Faced Rock-fill Dam under complex loading conditions. The model can overcome the shortcomings of classic elastoplastic model (i.e. soil behaviors under cyclic loading-unloading can be predicted). Elastoplastic formula of the model was presented in detail. Then this model was verified with test results of coarse grained soils, under both monotonic loading and cyclic loading-unloading conditions. This model was also applied to analyze deformation of Shuibuya rock-fill dam, computed results and in-situ measurements are compared. Results showed that computed results were consistent with in-situ measurements in both construction and operation period. Results also showed that permanent deformation that was caused by fluctuations of the reservoir level can also be predicted by this rotational kinematic hardening model.
Study of Carbon Thin Film Deposition on Various Buffer Layer as Characterized by X-Ray Diffraction and Raman Spectroscopy
Authors: Virdian Angga , Alfiadi Heldi , Darma Yudi
Published: July 2015

Westudy the structural characteristic of carbon based thin filmprepared by DC unbalanced magnetron sputtering technique on different buffer layer such as γ-Al2O3, SnO2, and Cu. Sputtering parameters of carbon thin film were maintained identical for each buffer layer. Fe-doped carbon pellet and Argon gas have been used as sputtering target and to generate the sputtering plasma, respectively. The roles of buffer layer for the quality of carbon-based thin film have been investigated by X-ray diffraction and Raman spectroscopy analysis. Raman spectra indicatethe formation of agoodquality carbon thin film with crystal-like structure on γ-Al2O3and Cu buffer layer, in contrast to the SnO2buffer layer case. Furthermore Raman spectra confirm thehoneycomb structure with fewer defects in γ-Al2O3 indicating that it is more suitable buffer layer than the other. We argue that γ-Al2O3 buffer layerprovide a good nucleation site and promote a better atomic arrangement for carbon atoms to form a few layergraphene-like structure. The atomic geometry of γ-Al2O3 supports the hexagonal atomic configurationfor carbon atom inthe formation of a few layers graphene. This study mightgive a new approach for the carbon based deposition towards the devices application.
Topographic and Electronic Properties of 3,4,9,10-Perylene Tetra Carboxylic Dianhydride (PTCDA) on Indium Tin Oxide (ITO) Surface
Authors: Arramel Arramel , Hasegawa Tsuyoshi , Tsuruoka Tohru , Aono Masakazu
Published: July 2015

We present the surface characterization and the local electronic properties of archetypical p-type perylene-based semiconductor organic molecule of Perylene Tetra Carboxylic Dianhydride (PTCDA) thermally evaporated on a transparent conducting metal oxide surface. A modified indium tin oxide (ITO) surface was successfully obtained by employing a subsequent chemical and physical treatment. Physisorbed PTCDA molecules exhibited a stacked-grain structure covering completely ITO surface. Scanning tunneling spectroscopy (STS) spectra of physisorbed PTCDA molecules were performed. In contrast to the previous studies of the homolog n-type perylene derivative thin films, here we successfully extracted both of the outmost frontier energy levels by measuring the current-voltage characteristics of PTCDA molecules in an estimated tunneling resistance from 4.17 to 100 GΩ at room temperature. Using numerical derivative of the I-V spectra, we extracted the series of transport gap of PTCDA molecule are lies in the region of 4.70-4.87 eV.
Optical Properties and Interband Transitions of ZnO and Cu-Doped ZnO Films Revealed by Spectroscopic Ellipsometry Measurement
Authors: Marlina Resti , Rusydi Andrivo , Darma Yudi
Published: July 2015

Optical properties analysis of ZnO and Cu-doped ZnO films on Pt substrate have been probed by using Spectroscopic Ellipsometry (SE) at room temperature. Here, we study the optical transitions and the evolution of excitonic states by means of the critical points (CP) analysis. The second derivative spectra of dielectric function (CP analysis) show the transition of excitonic peak at the fundamental absorption edge (E0). Corresponds to e1 spectra, the peak of refractive index (n) at around 3.3 eV is broaden by introducing Cu dopant. This peak is assigned as excitonic states and the peak broadening is mainly due to the screening of excitons. This excitonic screening is more pronounced in the second derivative spectra of dielectric function where the peaks intensity is decreased upon Cu dopant. In additions, effective number of carrier concentrations of ZnO film shows a high number as high as ~1022 cm-3. Furthermore, the addition of Cu doping -in this case 8 in at.%- does not significantly affect the effective number of ZnO film carrier concentration. This result confirms the strong interaction between ZnO film and Pt substrate and negligible contribution of Cu dopant for carrier concentration.
Simulation of Dirac Electron Tunneling Current in Armchair Graphene Nanoribbon Tunnel Field-Effect Transistors Using a Transfer Matrix Method
Authors: Suhendi Endi , Syariati Rifky , Noor Fatimah A. , Kurniasih Neny , Khairurrijal Khairurrijal
Published: July 2015

We simulate quantum mechanical tunneling current in armchair graphene nanoribbon tunnel field-effect transistors (AGNR-TFETs). The relativistic Dirac equation is used to determine electron wave functions in the AGNRs, while the potential profile is solved by the Poisson equation. We use a transfer matrix method (TMM) to calculate the electron transmittance and the Dirac electron tunneling current in the AGNR-TFETs. The results show that the Dirac electron tunneling current increases with increasing the drain and gate voltages. Moreover, the AGNR width and the thickness of insulator affect the characteristics of the Dirac electron tunneling currents.
Development of Emulsion Gels and Macroporous Hydrogels and their Applications to Metal Adsorption and Enzyme Reaction
Authors: Tokuyama Hideaki
Published: July 2015

Emulsion gels, that is, hydrogels containing randomly distributed oil microdroplets, and macroporous hydrogels with randomly distributed, non-interconnected, sphere-like macropores with several micrometers in diameter were prepared by the emulsion-gelation method [1]. This method involves the synthesis of hydrogels in an oil-in-water (O/W) emulsion by free radical copolymerization of a monomer with a cross-linker, followed by the washing (removal) of the dispersed oil as a pore template (porogen). The observations of oil droplets in an emulsion and internal structure of a macroporous hydrogel demonstrate that the oil droplets act as a pore-template. The pore size and porosity can be adjusted by varying the O/W volume ratios and surfactant amounts [2]. These gels are used as a bulk and have excellent diffusional permeability to a solute and solvent. The emulsion-gelation method can yield potentially intelligent gels in which the macropores function as spaces for reaction, separation and storage. Novel emulsion gel adsorbents, that is, polymeric hydrogels containing randomly distributed microdroplets of an organic extractant (an oil-soluble complexing agent), were developed for metal adsorption [3,4]. The emulsion gel containing an organophosphorus extractant and organosulfur extractant successfully adsorbed In (III) and Pd (II) ions, respectively. Novel macroporous polymeric hydrogels were developed to entrap and immobilize lipase as a model enzyme [5]. The lipase immobilized within the macroporous hydrogel successfully catalyzed the hydrolysis of triacetin in a model enzyme reaction without leakage of lipase or loss of activity during repeated use.
Application of Immobilized Titanium Dioxide as Reusable Photocatalyst on Photocatalytic Degradation of Methylene Blue
Authors: Sutisna Sutisna , Rokhmat Mamat , Wibowo Edy , Murniati Riri , Khairurrijal Khairurrijal , Abdullah Mikrajuddin
Published: July 2015

Titanium dioxide particles immobilized on polypropylene copolymer surfaces (TiO2/PC) have been successfully performed using a simple electrostatic-heating coating (EHC) method. The coating process was initiated by generating electroctatic charges on the polymer surfaces, followed by adhering TiO2 particles electrostatically onto the surface and completing with pressing at 110 o C for 4 minutes. The coated sheets have been applied to degrade methylene blue (MB) solution as a wastewater model under a direct sunlight exposure. Ten layers of TiO2 coated sheets produced the optimum decomposition rate with photodegradation effectiveness up to 99.30% for 4 days exposure. These materials are also repeatedly used, indicated by nearly unchange in the photodegradation effectiveness. After four times repetition, the coated sheets still function well by decomposition up to 99 % of MB compound. The material has potential for large scale wastewater treatment in the tropical regions.
The Role of Fe2+ Ions on the Photocatalytic Reaction of Ag3PO4 for Rhodamine B Degradation
Authors: Riapanitra Anung , Futihah Intan , Sulaeman Uyi , Yin Shu , Sato Tsugio
Published: July 2015

The Ag3PO4 crystal with 200-600 nm in diameter was successfully synthesized using co-precipitation method with AgNO3 and Na2HPO4.12H2O as starting materials. The product was characterized using XRD, DRS, FTIR and SEM. The photocatalytic activities were evaluated under blue light irradiation assisted by Fe2+. The 1 mL of Fe2+ aqueous solutions consisted of 1.00, 0.10, 0.01, 0.001 and 0.0001 mM Fe2+ was added into a 100 mL solution of Rhodamine B, and the photocatalytic oxidation of Rhodamine B was carried out under visible light irradiation. The highest photocatalytic activity was observed when 1 ml of 0.001 mM of Fe2+ aqueous solution was added in the Rhodamine B solution. The result inferred the possibility of in-situ peroxide generation during the photocatalysis reaction.
Photocatalytic Oxidation of Hexanol over Titanium Dioxide Supported on Mesoporous Silica
Authors: Mohd Nor Nur Umisyuhada , Lintang Hendrik O. , Endud Salasiah , Yuliati Leny
Published: July 2015

In order to improve the efficiency of TiO2, material with large surface area such as mesoporous silica is usually used as a support. In this study, the TiO2 was dispersed on mesoporous silica, MCM-41 by an impregnation method, meanwhile the bulk TiO2 was prepared by sol gel method. The X-ray diffraction (XRD) patterns showed that the intensities of diffraction peaks for MCM-41 decreased with the increase of the TiO2 loading, suggesting that the higher loading amount of TiO2 might lead to less ordered structure of MCM-41. The successful addition of TiO2 on MCM-41 was also confirmed from the fluorescence spectra, which the emission intensities of TiO2 and MCM-41 increased and decreased, respectively, with the increase of TiO2 loading on the MCM-41. The activities were compared between the bulk and dispersed TiO2 for photocatalytic oxidation of hexanol. Both bulk and dispersed TiO2 on MCM-41 showed good photocatalytic activity, while the MCM-41 did not show photocatalytic activity. Since the efficiency of photocatalyst can be defined by its respective turnover number (TON), the comparison between bulk and dispersed TiO2 on MCM-41 was made based on their TON values. It was revealed that the dispersed TiO2 on the MCM-41 with 5 wt% of TiO2 loading was the most efficient photocatalyst among all the samples.
Synthesis of CuFe2O4-Bentonite Composite for Adsorption of Ni(II) from Electroplating Wastewater
Authors: Hariani Poedji   Loekitowati , Riyanti Fahma , Fatma Fatma , Sutrini Siska
Published: July 2015

CuFe2O4-bentonite composite successfully synthesized using chemical co-precipitation method and using to adsorp Ni(II) from electroplating wastewater. The composite was characterized by Fourier Transform Infra Red and Scanning Electron Microscope-Energy Dispersive X Ray Spectroscopy. The FTIR spectra of CuFe2O4-bentonite composite presented the characteristic of CuFe2O4 and bentonite. Typical of bentonite obtained by the bands at 1033.8 cm-1 correspondent to the intensity of Si-O. The observed two peaks at 432.0 cm-1 and 536.2 cm-1 attributed to the tetrahedral and octahedral of CuFe2O4. The result indicated that CuFe2O4 particles deposited on the surface of bentonite. The main component of CuFe2O4-bentonite composite contained of CuFe2O4 and bentonite from EDX spectra. Batch experiments were carried out to investigate optimum condition of adsorption Ni(II) onto CuFe2O4-bentonite composite. The optimum condition for initial concentration of Ni(II) 50 mg L-1 and volume 50 mL obtained at weight of CuFe2O4-bentonite composite of 100 mg, contact times at 60 minutes and pH of the solution 5. The adsorption efficiency of Ni(II) from electroplating wastewater using CuFe2O4-bentonite composite at optimum condition was 99.136 %, respectively.
Graphene and Activated Carbon Based Supercapacitor Electrodes
Authors: Deraman Mohamad , Nor N.S.M. , Basri N.H. , Dollah B.N.M. , Soltaninejad Sepideh , Daik Rusli , Omar Ramli , Hashim@Ismail Mohd Azman , Othman Mohd Amir Radhi
Published: July 2015

Supercapacitor electrodes in the monolithic form were prepared by carbonization and activation of green monoliths (GMs). The GMs and composite GMs were prepared from self-adhesive carbon grains (SACG) of oil palm empty fruit bunches and SACG added with 2 wt.% of multi-layers graphene, respectively. Both GMs and composite GMs were subjected to 18 h and 36 h milling time, respectively. The structure and porosity of the electrodes observed in the Raman spectroscopy and nitrogen adsorption-desorption results, respectively, indicated the effects of graphene addition and doubling the milling times. Galvanic charge discharge results of the supercapacitor cells fabricated using these electrodes showed that the greatest improvement due to the graphene addition occurred for the electrodes prepared based on the lower milling time. The results obtained from the electrochemical characterization showed that specific capacitance, specific power and specific energy of the cell with electrodes from the composite GMs produced from the mixture milled for 18 h were 46 F g-1, 165 W kg-1 and 1.2 W h kg-1, which were ~500 %, ~25 % and ~1100 % better than the other cells.
Enhancing the Value of Local Silica Sand from Bancar as a Fuel-Cell Sealing Material
Authors: Dewa Egidius , Musyarofah Musyarofah , Nurbaiti Upik , Triwikantoro Triwikantoro , Firdaus Sukma , Suminar Pratapa
Published: July 2015

A prospective fuel cell sealing material using silica sand from Bancar, Tuban, East Java has been investigated. The investigation was aimed to enhance the value of such natural sand and was started by a treatment using magnetic separation and immersion with HCl to produce pure silica powder. Ceramic composites were then synthesized by a solid state reaction method by mixing the silica powder, magnesia (MgO), and 5-20wt% of boria (B2O3), pressing the mixture into pellets and finally sintering them at 1150 °C for 4 hours. By Archimedes method, it was found that the addition of B2O3 is favorable to reduce the porosity of composites with a maximum value reaching 0.68(0)% for the composite with 20% B2O3. An X-ray diffraction technique revealed that a liquid phase sintering had occurred, indicated by the appearance of quartz (SiO2), forsterite (Mg2SiO4) and protoenstatite (MgSiO3) in the sample without B2O3 and quartz and protoenstatite in the composites with 5 and 10 wt% of B2O3. Meanwhile, the composite SMB15h, in addition to quartz and protoenstatit, also contains a new phase, namely suanite (Mg2B2O5). In SMB204h, there are quartz and suanite.The phase compositions were determined using the Rietveld method from which thermal expansion coefficient values of 9.5-12 ppm °C-1 had been predicted. These results showed that natural-sand-based composites could fairly satisfy the required conditions of fuel-cell sealing materials.
Evaluating Capacitive Deionization for Measurements of the Salt-Removal of NaCl, KCl and MgCl at Various Cell Voltages
Authors: Anggoro Diky , Endarko Endarko
Published: July 2015

Carbon electrodes have been successfully synthesized and characterized for desalination system based on Capacitive Deionization (CDI) technology. The carbon electrodes were synthesized with an activated carbon (700 – 1400 m2/g), carbon black, glutaric acid and polyvinyl alcohol as a binder using cross-linking method at 120 °C. The study was to investigate salt removal percentage value of 0.1 M NaCl, MgCl and KCl using CDI cell. A solution with 0.1 M was supplied to the cell using a Boyu Submersible pump (model SP-601) at a ﬂow rate of 10 mL/min. When potentials of 1.0, 2.0, and 3.0 V were applied to the CDI cell, the result showed that a solution of 0.1 M KCl has greater salt-removal percentage than the solutions with 0.1 M NaCl and MgCl. The salt-removal percentage of KCl was achieved at 55% for 3.0 V whilst resulted in 20 and 30% for NaCl and MgCl, respectively.
Effect of Al2O3  on the Electrical Conductivity of MgI2-Mg3(PO4)2 Solid Electrolyte
Authors: Ahmad Azizah Hanom , Aziz A.
Published: July 2015

MgI2 and Mg3(PO4)2 were mixed in varied compositions and the mixture was subjected to ball milling and sintering process. The optimum composition of the binary system with the maximum conductivity of 5.72 x10-4 Scm-1 at room temperature was obtained and used to study the effect of ceramic filler. A small amount of Al2O3 was added to the 0.7 Mg3(PO4)2 0.3 MgI2. The effect of ceramic filler on the electrical conductivity of the binary compound is investigated by Electrical Impedance Spectroscopy (EIS) technique in the frequency range from 50 Hz to 1 MHz. The conductivity was enhanced to 1.08 x 10-3 Scm-1 when 4 wt. % of Al2O3 was added. Further characterization was performed by using Infrared (FTIR) technique. From FTIR spectra, the variation in the peak intensity and shifting were observed which is due to the interaction between O-OH on the filler grain surface.
Theoretical Investigation of Anthocyanidin Aglycones as Photosensitizers for Dye-Sensitized TiO2 Solar Cells
Authors: Cahya Prima Eka , Yuliarto Brian , Suyatman Suyatman , Dipojono Hermawan Kresno
Published: July 2015

The aim of this study is to analyze dye electronic properties of anthocyanin aglycones to be used as photosensitizers for TiO2 solar cells. The dye properties will be examined by the density functional theory (DFT) method at IEF-PCM(UFF)/B3LYP/6-31+G(d,p) levels under ethanol and water environments. The results show that the position of LUMOs of all dyes lying over TiO2 ECB will facilitate good electron transfer while their HOMOs, which are lower than the electrolyte redox potential energy, can facilitate good oxidized-dye regeneration. Flavilium cation dye is the best anthocyanidin aglycone due to the best electron injection spontaneity of -0.807 eV as well as the highest open circuit voltage of 1.669 V. On the other hand, quinonoidal base dye gives the best light harvesting efficiency of 69.24% due to the best oscillating strength character. Moreover, the solvent effect is the important aspect regarding the dye oxidation potential stabilization as well as the electron injection driving force.
The Synthesis of Ethyl-1-Benzyl-5-Methyl-1H-1,2,3-Triazoles-4-Carboxylate Using Microwave Assisted Organic Synthesis Method and Determination of its Corrosion Inhibition Activity on Carbon Steel
Authors: Syifa Insani Rayyane Mazaya , Wahyuningrum Deana , Bundjali Bunbun
Published: July 2015

This study has successfully conducted the development method of synthesizing ethyl-1-benzyl-5-methyl-1H-1,2,3-triazoles-4-carboxylate utilizing Microwave Assisted Organic Synthesis (MAOS) method. Synthesis has been carried out in two stages. The first stage was the formation of benzyl azide (1) from the reaction between sodium azide and benzyl bromide using conventional method. In the second stage, product 1 was reacted with ethyl acetoacetate in the catalytic base of potassium carbonate using MAOS method to form ethyl-1-benzyl-5-methyl-1H-1,2,3-triazoles-4-carboxylate (2) with melting point of 75-77 °C and chemical yields of 37.5%. Measurement of compound 2 using mass spectroscopy TOF MS ES+ showed peak at 245.1244 corresponding to molecular formula C13H15N3O2. Structure elucidation has been confirmed through IR, 1H NMR, and 13C NMR spectroscopies. Corrosion inhibition test of compound 2 was conducted using Electrochemical Impedance Spectroscopy (EIS) on carbon steel in 1% (w/v) NaCl saturated with CO2. The largest corrosion inhibition efficiency of 2 was obtained at 45 °C and the concentration of 70 ppm, which is 91.54%. The ∆Gadsvalue of compound 2 at room temperature is 38.48 kJ/mole which corresponds to the semi-chemisorption or semi-physiosorption mechanism of compound 2 on the metal surface according to Langmuir adsorption isotherm.
Analysis of YSZ-Al2O3/YSZ Flame Sprayed Thermal Barrier Coating to Thermal Resistance
Authors: Widyastuti Widyastuti , Parindra Kusriantoko , Mariani Lilis , Ardhyananta Hosta , Sulistijono Sulistijono
Published: July 2015

TBC (Thermal Barrier Coating) with YSZ-Al2O3/YSZ as top coat (TC) and MCrAlY alloy as bond coat (BC) marked as YSZ-Al2O3/YSZ double layer TBC was used for thermal barrier material on rocket nozzle wall. Several test have been conducted (thermal test and SEM-EDX). Thermal test was divided into two part, Thermal Torch and Non-isothermal Oxidation Test which is used for measure the resistance of TBC structure against oxyacethylene flame penetration as a miniature of thermal static test for rocket nozzle until the specimen was failure and used to measure the resistance against non-isothermal oxidation as well as investigate the growth of TGO (Thermally Grown Oxide) layer on interface between TC/BC for thermal torch and non-isothermal oxidation test respectively. This test was performed at 1100o C with 10°C/min heating rate. The results showed that the improvement of feed rate on topcoat powder gave the effect on the surface morphology of topcoat. Lower feed rate bring in a coarse surface morphology and tend to be porous. Al2O3/YSZ composite layer affect on the growth of TGO layer after thermal test, which indicates the lower growth of TGO especially for 15%Al2O3/8YSZ. TGA test showed that the sample began to oxidize at temperature range c.a 1000 – 1030°C, however 1st derivative analysis indicated that 15% Al2O3/8YSZ, 14 g/min was the most stable sampel. Moreover this material has a good resistance from torch destruction.
Objective and Combinational Analysis of Multiple Kinds of Data Obtained from Severe-Mild Wear Transition
Authors: Fukuda Kanao , Morita Takehiro
Published: July 2015

The authors have been developing objective and combinational analysis method for multiple kinds of data obtained by a repeated sliding test performed with a pin-on-disk apparatus to clarify the wear mechanisms. The developed analysis method successfully showed the growth rate and the size of adhered substances on the sliding surface for adhesive wear mechanism. In this paper, the developed method was applied for analyzing chronological changes in severe-mild wear forms transition to understand the phenomena more quantitatively. Friction force, pin specimen displacement perpendicular to the slid surface and electrical contact resistance between pin and disk specimens were employed as the multiple kinds of data. The devised analysis showed that the formation of a plateau with around 25 μm height on the slid surface is a key factor for the transition.
Effect of Pack Cementation Temperature on Oxidation Behavior of NiCoCrAl Coated Layer
Authors: Sugiarti Eni , Zaini Kemas A. , Wang Yong Ming , Hashimoto Naoyuki , Ohnuki Somei , Hayashi Shigenari
Published: July 2015

The oxidation behavior of NiCoCrAl coatings deposited on carbon steel was evaluated at 800 °C for 100 h in atmospheric air. The effect of different coating process on the oxidation of carbon steel was studied. The oxidation mechanism was discussed based on oxidation rate, formation of oxide scale, and microstructure of the coated sample. The oxidation rate significantly increased owing to the formation of metastable Al2O3 during initial oxidation stage. The oxidation rate decreased due to the transformation from d, q to a-Al2O3 from the intermediate stage up to final stage of 100 h oxidation. The effect of pack cementation temperature contributed to the thickness and diffusion of coated elements. The experimental results showed that sample developed at 800 °C exhibited better oxidation resistance than sample developed at 900 and 1000 °C.
Curing Time and Water Repellent Properties of Dammar-Titanium Dioxide Thin Film
Authors: Hasnan Aisyah Nor , Ahmad Azizah Hanom
Published: July 2015

Dammar plant resin is a local natural resin that can be bled from Dipterocaupacea sp of tree. It can be found abundantly in Malaysia’s tropical forest especially in Sarawak. Dammar and Titanium Dioxide was mixed in a various wt% to produce Dammar-modified Titanium Dioxide coating system. The modified coating systems were then spin-coated onto Aluminium Q-panel as the substrate. Coated Q-panels were left to cure at room temperature. The curing time was evaluated using dust free stage. The addition of Titanium Dioxide into the coating system fastens the curing time taken for the coated Q-panel to be cure. It only took about 11-12 minutes to dry compared to the coating system before the addition of Titanium Dioxide where a quite long duration required, 32 minutes. Contact angle measurement was also carried out in order to determine the wettability of the coating system. The surface coated with dammar-modified titanium dioxide found to be hydrophobic where a quite large contact angle obtained for the sample with 3 wt% of Titanium Dioxide (PDT3). The water droplets actually rest on the coating surface without wetting the surface. Water absorption test was done to strengthen the contact angle results where coated substrate was soaked into distilled water for 24 hours and being weighed before and after soaking. The difference of before and after soaking weigh showed that the coating surface does not absorb that much water where only approximately 0.02% of water being absorbed by the coating system for 3 wt%. It proved that the coating systems applied are hydrophobic.
Effects of Stabilization Temperature on the Chemical and the Physical Properties of Polyacrylonitrile Stabilized Fibers
Authors: Binti Yusof Norhaniza , Ismail Ahmad Fauzi , Jaafar Juhana , Salleh W.N.W. , Hasbullah H.
Published: July 2015

The present work dealt with the preparation of carbon fibers from Polyacrylonitrile (PAN)/ acrylamide (AM) fibers via a solvent-free coagulation process. The PAN/AM fibers were stabilized in an oxidizing atmosphere at various temperatures (200, 250, 275, and 300 °C), while the stabilization time was fixed at thirty minutes. The effects of stabilization temperature on the chemical and the physical properties of the prepared stabilized fibers were studied. The chemical structure evolutions of stabilized fibers (SFs) from the precursor fiber were observed with FTIR studies, whereas the microstructure properties were thoroughly characterized with SEM studies. The mechanical strengths of the SFs were obtained from the Young Modulus and the tensile strength analyses. Stabilization temperature at 275°C had been identified as the optimum stabilization temperature for the PAN/AM fibers.
Reduction of Harmful Substances in Cigarette Smoke Using TiO2 Nanoparticles
Authors: Murniati Riri , Sutisna Sutisna , Wibowo Edy , Rokhmat Mamat , Surtiyeni Neni , Yuliza Elfi , Khairurrijal Khairurrijal , Abdullah Mikrajuddin
Published: July 2015

Both qualitative and quantitative effect of TiO2 suspension presence in cigarette filter have been analyzed in order to reduce harmful substances in cigarette smoke, optimizing the capability of TiO2 suspension as nano filter in cigarette filters and reviewing the analysis in order to obtain results with the best variation. Samples in the form of filter paper that has passed of the smoke with some variation treatment as it become ready to be tested and analyzed. Parameter such as concentration and volume variation of TiO2 suspension, and also the inputting method of TiO2 suspension into cigarette filter. Samples were characterized using FT-IR spectrophotometer and samples data absorbance obtained in each catchment area. The results showed that by reducing absorbance value percentage of each catchment area, with inputting method of TiO2 suspension through the cigarette filter tip and base, it appears that the most stable and lowest reduction present in C3 and H3, which is sample with 1.85 mol/liter concentration and 0.3 ml suspension volume. Both sample reduced particulate matters significantly after confirmed with X-Ray Fluorescence and SEM-EDS results, and was compared to sample filter without TiO2. Inputting method of TiO2 suspension through a base of cigarette butt is better and safer than through end of cigarette filter.
Wax-Impregnated Cotton Fabrics as Cell Culture Platform
Authors: Wahab Norsamsiah Muhamad , Abdul Jamil Syazwani , Riban Dwi Gustiono , Abdul Majid Fadzilah Adibah , Abdul Kadir Mohammed Rafiq , Wicaksono Dedy Hermawan Bagus
Published: July 2015

Microwell plates are widely used in various cell-based assay and drug screening. Usually these plates are made from non-biodegradable materials such as polystyrene or polyethylene. In this report, we propose the use of wax-impregnated cotton fabrics as an alternative microwell plate that is easy to fabricate, simple to use, sustainable and environmentally friendlier. Several researchers recently used soft lithography and photolithography technique to fabricate various cell culture platforms. Our proposed method consists instead of simple dipping and drying process. The platform is made of a series of fabrics being stacked and held together with various wax formulations. With the exception of the base layer, each fabric layer has a circular hole opening with increasing diameter towards the top layer; thereby forming a well where cells are cultured at its flat bottom. We characterized the chemical and physical properties of the platform surface which affect cells attachment and proliferation. These properties include the surface chemistry, hydrophobicity and roughness. We cultured human skin fibroblast (HSF 1184 Cell Line) on the platform as our preliminary proof of concept. We observed proliferation of the cells after 24 hours. The result indicates the potential use of the platform for future cell-based assay applications.
Microstructure and Mechanical Properties of Extruded Mg-1.6Gd as Prospective Degradable Implant Materials
Authors: Susanti Oknovia , Harjanto Sri , Mochtar Myrna A.
Published: July 2015

Mg-1.6 Gd alloy ingot were prepared by hot extrusion. The extruded alloy exhibits the recrystallised grain size and excellent mechanical properties. The aim of this study is to explore the microstructure and mechanical properties of extruded Mg-1.6 Gd to be used as implant. Extrusion was performed at temperatures of 400°C, 450 °C, 500°C and 550°C with a speed of 1mm/s and extrusion ratio of 30%. Tension and hardness testing were carried out on samples taken from extruded rod of Mg-Gd alloy. Microstructure observation revealed that all extruded alloy specimens constitued of finer grain size (~14 um) compared to that of the as-cast alloy (> 500 um) as the result of full recrystallization occured at 400 °C. The grain size increased larger with an increase temperature and the peak value is 25mm at temperature of 550 °C. Hardness of the alloy decreased as the extrusion temperature increased from 48.7 HV at 400 °C to 42 HV at 550 °C which is associated with the change in the grain size. Tensile strengths were not apparently affected by the temperature change, however, it was observed that the tensile and yield strengths dropped at 500 °C. Meanwhile, the elongation decreased with increasing temperature which reached 24 % at the lowest temperature. Detailed explaination of the relationship of microstructure and mechanical properties is discussed in this paper.
Study on the Geopolymerization of Geothermal Silica and Kaolinite
Authors: Olvianas Muhammad , Najmina Mazaya , Prihardana Bernardo Saktya Ludy , Sutapa Fransiskus A.K.G.P. , Nurhayati Anis , Petrus Himawan Tri Bayu Murti
Published: July 2015

Geothermal plant produces numerous kinds of possible side products. One of them is silica as a consequence of the existing silica scaling problem which causes geothermal power plant efficiency depletion. The silica recovery possesses a way to utilize it. Geopolymer concrete is a solution to utilize the abundance recovered geothermal silica with low energy consumption and green house gas emission. Thus, in this study, the geopolymerization of geothermal silica and kaolinite will be observed. Geopolymer was inorganic polymer consist of Si and Al atoms that formed through polymerization process. The raw materials being used are geothermal silica as amorphous silica source and kaolinite as alumina source, whereas the activator composed of sodium hydroxide and sodium silicate. Geothermal silica possesses amorphous structure which had been proven by X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF) analysis with 96.09% silica (SiO2) content and 18.92% alumina (Al2O3) content of kaolinite. The experiment conducted to determine geopolymerization rate of geothermal silica and kaolinite reaction in presence of alkali activator with certain composition and temperature variation ranged from 80°C up to 120°C. Study on geopolymerization rate was carried out by observing geopolymer bond along with the compressive strength as a function of curing time and temperature. As for geopolymer bonds for each sample with different curing temperatures, FTIR and SEM analysis were used to investigate.