bluuebunny/crossref_metadata_2025 huggingface dataset:
Copper Doping TiO2 Nanotube Arrays Loaded with Hydrophilic and Hydrophobic Drugs and its Release
Authors: Zhang Feng Fen , Xie Chun Lin , Yang Xiao Juan , Xiao Xiu Feng
Published: October 2017

In this work, vertically aligned titania nanotube arrays (TNTs) were fabricated on Ti surface in fluoride-containing electrolytes by anodization. TNTs were treated by hydrothermal treatment in the saturated solution of [Cu(NH3)4 (H2O)2]2+. Different hydrothermal treatment conditions were studied to obtain the best modification effect in the experiment. The TNTs were loaded with alendronate and ibuprofen via vacuum drying method and the release properties from the nanotubes were detected in phosphate buffer solution (PBS). The samples were characterized by field emission scanning electron microscopy, X-ray diffraction, and UV-Vis spectrophotometer. The data show that copper is successfully doped to the nanotube surface by hydrothermal treatment, and the optimum hydrothermal treatment conditions are 200°C, 0.5h. The drug loading capacity of the modified sample increased obviously, whether it was hydrophilic or hydrophobic. Meanwhile, the modified nanotubes release more slowly in the later stage. This approach provides an alternative to tailor the surface of TNTs and offer considerable propects for diverse biomedical applications.
Effects of Tunable Angle for Vortex Generators on Aerodynamic Performances of Airfoils
Authors: Yu Hu , Yang Bin Tang , Sun Xiao Qing , Wang Xi , Mo Hang Jie
Published: October 2017

Vortex generators (VGs) are commonly adopted to control the flow separation, and many researches have investigated their effects on the aerodynamic performance of wind turbines. However, nearly no attentions are paid to the VGs’ installation angle. Thus, in this paper, to investigate the effects of the VGs’ installation angle on airfoils, numerical simulations are conducted by CFD on the finite wing of NACA0012. According to the finite airfoil with or without VGs, three-dimensional models are established and numerical simulations are carried out in detail. It could be seen clearly that the VGs’ installation angle produces a significant impact on the aerodynamic performances. For some installation angles, special ranging from 45° to 90°, VGs can improve the lift-drag ratio apparently, even by 34.5%. While angle ranges from 15° to 30°, VGs negatively influence the lift-drag ratio. Furthermore, the fluctuation phenomenon is discussed through analysis of the streamlines and vortices. Based on those results, optimal aerodynamic performances could be achieved by the active control of the VGs’ installation angle.
Formula for Calculating Pressure Distribution of Crude Oil Flowing through 180 Degree Bend
Authors: Lu Xiao Yang , Wang Lu Lu , Huang Li Li , Lu Shao Bo , Wang Xiao Xiao
Published: October 2017

FLUENT software was used to analyze the distribution of internal pressure P of elbow with the variation of outlet pressure P0, inlet velocity v, fluid density ρ and the degree of curvature k=R/D during the flow of crude oil in 180 degree bend pipe, to establish 135 kinds of working condition of internal pressure P distribution database. According to the distribution law of the pressure of the inner wall of the elbow under different parameters (P0, v, ρ, k), calculation formula of the internal pressure distribution of the pipe is analyzed and fitted by 1stOpt software. Through the numerical simulation results of 11 kinds of working condition of FLUENT, the calculation precision of the formula was verified (Maximum relative error). It provides basis for design of bend pipe and safety evaluation of pipeline in high pressure, high flow rate and long distance petroleum pipeline.
Design of Sleeve Piling Machine and Finite Element Analysis of the Sleeve Tubes
Authors: Zhang Ze Yu , Hui Ji Zhuang , Yan Chang , Cheng Shun Peng , Suo Xue Feng
Published: October 2017

In order to solve the problems of the easy breakage, transport problems and pile holes shrinkage, a sleeve piling machine was designed. It included a fully used pile frame, a novel pile driver and its piling method. The piling machine integrated the advantages of the diesel hammer piling machine and the vibration hammer piling machine. It is suitable for bored piles and compacted piles. Based on the sleeve pile tubes, the diesel hammer and the vibration hammer worked together to drill. Then the reinforcing cage was lifted by the hoister, the pile tubes were pulled and the concrete were poured with the help of the vibration hammer. All of them can avoid the shrinkage of the pile, the break of the pile, and improve construction efficiency. Besides, finite element analysis of the pile tubes were calculated by ANSYS, the results showed that the strength of the pile tubes was satisfied with the requirements of application. The piling machine and the method were feasible.
Design of a Bicycle Wheel with Shock Absorption Ability
Authors: Hou Shuai Song
Published: October 2017

Wheel is an important part in the overall structure of bicycles. So performances of wheels have a great influence on the performances of bicycles. For example, if we improve the shock absorption of wheels, the bicycle will have better riding comfort. Traditional bicycle wheel absorbs shock from rough roads using the tire. In this paper, we propose a new design concept for the bicycle wheel with shock absorption ability. Firstly, we perform force analysis for the bicycle wheels. In order to verify our calculation, we conduct the finite element simulation analysis. The calculations and simulations have good consistency. Based on the calculations and simulations, we replace the steel spokes with some soft materials. Through impact test, we find that the bicycle with shock absorbing wheels has better riding comfort than traditional one. Meanwhile, the soft materials reduce the weight of wheels. So the overall performances of bicycle are improved significantly.
Strength Analysis of Efficient Linear Pumping Unit
Authors: Guo Feng , Wang Sen , Zhao Yang Yang , Li Si Yang , Ren Yan Long , Chen Chen , Sun Lin , Xu Hai Biao , Gao Qing Zhong
Published: October 2017

In order to avoid the pumping unit damaging caused by strength failure in actual work, this paper builds reliability calculation formula and reliability point estimation model based on SSI. The finite element simulation software is used in this paper to simulate the internal stress of the pumping unit and the strength of oil-conveying pipe. This paper also analysis the oil pressure distribution of the pumping unit internal and the oil-conveying pipe and the deformation degree of the pipeline in normal work. The research results confirm that the stress is much weaker than the material strength, which indicates that the design of the strength is reasonable.
Temperature Field Analysis of High Efficiency Linear Pumping Unit
Authors: Liu Yan , Wang Sen , Zhao Yang Yang
Published: October 2017

The generation of heat source of high efficiency linear pumping unit was analyzed. The calculation method of motor loss and heat dissipation coefficient was given. The finite element analysis software was used to simulate and analyze the temperature field of the linear pumping unit in the phase of constant motion and the starting and reversing phase. According to the analysis, it was concluded that the reasonable optimization of linear motor cooling structure can ensure the good temperature characteristics.
Aluminum Foam Sandwich with Different Face-Sheet Materials under Three-Point Bending
Authors: Yan Chang , Song Xu Ding , Feng Shuo
Published: October 2017

Aluminum foam sandwich structure is a new type of composite material with excellent mechanical and functional properties. As it is known that properties of aluminum foam sandwiches (AFS) vary if the foam core is sandwiched between different face sheets. To study the effects of face-sheet materials on the mechanical properties of AFS and enable a better understanding of the usage of such AFS structures under flexural load, AFS sandwiched by 6061-aluminum alloy face-sheets and 304 stainless steel face-sheets were fabricated and investigated under three-point bending by using WDW-T100 electronic universal tensile testing machine. Results showed that 6061-aluminum alloy reinforced AFS had the same peak load value with 304-stainless steel reinforced one almost so long as the thicknesses of the face-sheet material were the same and the foam core densities were the same too, but the energy absorption ability of 304-stainless steel reinforced AFS was much higher than that of 6061-aluminum alloy reinforced. However, the integrality of the 6061-sandwiched AFS was better than 304-sandwiched AFS. Deformation modes of the two types of AFS were also discussed in the present study.
Rocker Arm Force Analysis of Crown-Block Heave Compensation System Based on ADAMS
Authors: Liu Zhen Dong , Zhang Yan Ting , Huang Lu Meng , Wang Kang , Shi Ming Bin
Published: October 2017

This paper compares three common installation ways of swing arm and carries out simulation analysis by using Adams software. The research results show that when using intercrossed enwinding wirerope, the swing arm will bear alternating load and the load variation range is huge, load G’ will change obviously and bring great impact on system control precision. When using along enwinding wirerope, the swing arm’s load is slightly bigger than wirerope tension and the load variation range is very small, load G’ will be static and it’s easy to get high control precision. By reducing the length of lower swing arm, increasing the length of upper swing arm and the offset distance, its working condition can be improved when using intercrossed enwinding wirerope.
Energy Consumption of Bio-Inspired Legged Walking Robot
Authors: Park Sung Ho
Published: October 2017

Terrestrial vertebrates can walk more elegant than any other man-made legged mechanical models, which yield unstable locomotion with low speed. They continuously have modified their body structure and living patterns for the survival. They still continue their development. Legs are basically a serial linkage of rigid bodies connected by joints and exactly correspond to the manipulator in robot. Structure of living creatures are copied and modeled with 12 links, 12 joints and body, from the mechanical engineering viewpoint. Iterative Newton-Euler method is applied to compute torques acting all joints, which are required to calculate the total consumed energy to complete one locomotion cycle. Mechanical energy efficiency of different variables or systems are evaluated and compared by specific resistance. Parameters, specifying structure and locomotion, are applied to the simulation and the optimal values which minimize energy expenditure in locomotion are derived.
Analytic Study on On-Line Model of Moisture in Hot Air Drying Process of Grain
Authors: Mai Zhi Wei , Wang Bi Ying , Li Chang You
Published: October 2017

This study aims to review variation pattern of moisture content ratio of grains in deep-bed drying process, guide the drying technology design, realize real-time tracking and regulation in drying process, improve the quality of drying process and reduce energy consumption. Based on the moisture diffusion model in thin layer drying process, the principle of mass conservation of deep drying process, state function and irreversible thermodynamics analytic method, we have established and solved basic equations of deep-bed drying of grains, obtained the moisture content ratio of grains and analysis formula of drying velocity distribution in processes of concurrent flow drying, counter flow drying, cross-flow drying and standing drying and resolved the sustained decreasing drying process of grains in the concurrent flow drying and extreme point of drying rate in the counter-flow drying. Under the same conditions of temperature, humidity and air output, the drying velocity in counter-flow drying significantly higher than that in the concurrent flow drying. It means the energy utilization effects in counter-flow drying is better than that in the concurrent flow drying. Drying characteristics of grains in cross-flow drying and standing flow drying are the same, while drying rates in inlet-air side and outlet-air side vary widely. It means that when the layer thickness is 0.5m and the moisture content is over 20%, the drying rate in outlet-air side is nearly zero and the drying uniformity is bad. Tests on 5HP-3.5 recirculation drier shows that maximum deviation between analytic value and measured value in deep drying process is 0.69% and the range scope is -0.27%-0.69%. From the drying characteristics of grains, deviations mainly come from instrument detection deviations. The analytic method has important significance for realizing real-time tracking and regulation in drying process, guiding drying technology design, reducing energy consumption, increasing drying rate and drying machine capacity.
Quality Inspection System of Circular Saw Blades Based on Eddy Current Inspection and Laser Measurement
Authors: Ma Xin Qiang , Ge Hai Long , Ma Jian , Cheng Wei , Ren Yuan
Published: October 2017

Aiming at the problem of the complicated process, the low precision and efficiency of crack detection and key geometric feature of the circular saw blade, the quality detection system of the circular saw blade based on the nondestructive testing and laser measurement technology is studied. By using the laser measurement technology and optimizing the data processing method, the face runout, the thickness of the circular saw blade are measured. The crack defects in the tooth root region of the circular saw blade are detected by eddy current nondestructive testing technology. The system achieves the radial detection of 1mm radial sawing, the detection accuracy of the round beating is> 0.03mm, and the thickness measurement accuracy is> 0.005mm.
A Case Study on Inner Corrosion of 3%Cr Casing Steel in the CO2 Environments
Authors: Xu Lin , Li Si Yang , Xu Ming Biao
Published: October 2017

Understanding inner corrosion property of casing steel is fundamental to safe and economic exploitation of oil & gas. In this present work, a series of corrosion tests were conducted on 3%Cr coupons derived from 9-5/8” casing. Analyses of weight loss, product morphology and composition were carried out, to investigate the corrosion behaviors caused by sweet CO2. Analysis on the weight loss showed that, with an increment of temperature from 45°C to 105°C, the corrosion rate of 3%Cr coupon firstly ascends and then arrives to the maximum at 65°C. SEM analysis demonstrated the formation of a compact corrosion product layer on the specimen surface. While increasing the exposed time increases, the corrosion rate gradually descends. The main compositions of corrosion product are Fe-Cr and Cr5O12, which can effective hinder corrosion reaction in the CO2 environment.
Neural Networks Model of Structural Damage Detection with Flexibility Matrix
Authors: Li Lin , Zhang Jun
Published: October 2017

As structural health problems are becoming more and more important, a neural networks model is introduced to detect structural damage. The structural modal flexibility matrix can be accurately constructed by the natural frequency and modal information. All elements of changes in the modal flexibility matrix are looked on as inputs of the networks. Damage locations and extents are both considered with different outputs in the present study. A simply supported truss structure is studied with different damage cases. To localize damage, one case is chosen as location input/target pairs to train the present BP network model. But to identify damage extent, two cases are chosen as extent pairs to train. Although modals of BP neural networks with different outputs are presented for different damage detecting schemes, it is more difficult to ascertain damage extent than location. The results indicate that the present BP neural network modal can effectively detect damage of structures with changes in the flexibility matrix between the intact and the damaged cases.
Study on Machining Damage of Helical Milling for C/E Composites
Authors: Xu Jun , Zhu Xiang Long , Kang Ren Ke , Yang Guo Lin , Guo Dong Ming , Dong Zhi Gang
Published: October 2017

Carbon fiber/epoxy resin composites (C/E composites) are wildly used in manufacture of aircraft fuselages and wings in aerospace industry, due to their excellent properties. However, hole making of C/E composites always results in machining damage, such as burr, tearing, delamination and so on. Milling tools with different shapes were used to conduct helical milling experiments on C/E composites. The influence of tool shape on machining damage was analyzed by measuring the damage area of burr, tearing and delamination. And then the feed speed, axial feed per orbital revolution and spindle speed was changed respectively to study the effect of processing parameters on machining damage. The machining damage can be reduced by choosing appropriate tool shape and processing parameters.
Structural and Thermal Diffusivity of Sm3+ Doped Willemite Glass Ceramics System from Waste Materials
Authors: Auwalu I.A. , Halimah Mohamed Kamari , Zaidan A.W. , Chan K.T. , Abdullahi U.
Published: October 2017

This study presents the formation of the zinc silicate from amorphous silica obtained from waste rice ash, with the addition of zinc oxide nanoparticles by conventional solid-state technique. The XRD showed the sharp intensive and small peaks while FTIR results indicated very slight variations in their peaks with the increased of samarium dopant concentrations. The FESEM clearly showed the cracks of zinc silicate doped with samarium the samples. The least thermal diffusivity values from 0.2039 to 0.1392 mm2/s acquired by pure zinc silicate (willemite) sintered at 1000°C. The thermal diffusivity was increasing with dopant concentration and decreasing with the rise in temperature (27-500°C). The thermal diffusivity curves revealed the exponential decay with the pores and cracks in the samples.
Lasing Efficiency of Nd3+-Doped Lead Tellurite Glass
Authors: Azman K. , Norihan Yahya , Azhan H. , Syamsyir S. Akmal , Nasuha R.S.
Published: October 2017

Neodymium doped tellurite glass have been proven to be one of the most efficient candidates for photonic application. Nd3+ ions are well known excellent as lasing ions at 1.06μm. However, the efficiency of the lasing activity of the Nd3+ doped tellurite glass need for more discussion especially on the contribution of the atom-atom and atom-ligand bonding based on the Judd-Ofelt theory. Therefore, initiative has been taken in this work to determine the laser efficiency by mean of their oscillator strength and Judd-Ofelt parameters. In order to identify the optical behaviour, good quality of Nd doped tellurite glass should firstly be ready. From the results, it is found that the experimental and calculated oscillator strength results of the glass are found varies from 1.157 x 10-6 to 0.804 x 10-6 and from 2.527 x 10-6 to 2.243 x 10-6 respectively with respect to Nd2O3 composition. The small rms deviation ~10% indicates good fit between experimental and calculated oscillator strength. Meanwhile, the Judd-Ofelt intensity parameters with t = 2, 4 and 6 are found to vary with respect to mol% of Nd content. The 4F3/2→4I11/2 transition for 1.06μm emission which is useful for lasers and optical amplification is totally contributed from electric dipole whereas the magnetic dipole shows no effect. Some other results will be discussed in details.
Effect of Nd3+ on the Properties of Lithium Niobium Borate Crystal and Glass
Authors: Kamaruddin Wan Hairul Anuar , Rohani Md Supar , Sahar Md Rahim , Liu Hong
Published: October 2017

1 mol% of neodymium-doped lithium niobium borate (NdLNB) glass and crystal have been produced by using melt-quenching and Czochralski technique, respectively. The synthesis, growth and characterizations of the samples were reported. X-ray diffraction (XRD), Differential thermal analyzer (DTA), Ultraviolet-Visible-Near-Infrared (UV-Vis-NIR) and Photoluminescence (PL) spectroscopic characterizations were made to examine the influence of Nd3+ on the physical, structural and optical properties of the samples. Various physical properties such as density, molar volume, ion concentration, polaron radius, inter-nuclear distance and field strength were calculated. The as-quenched glass was amorphous whereas crystal was crystalline as established via XRD studies. UV-Vis-NIR spectra exhibited eight prominent bands centered at 353, 475, 524, 583, 681, 745, 803, 875 nm corresponding to the transitions from the ground state to 4D3/2, 2G9/2, 4G7/2, 4G5/2, 4F9/2, 4F7/2, 4F5/2, 4F3/2 excited states, respectively. Moreover, the emission spectra at 355 nm excitation displayed several peaks that contributed to the transition of(4F3/2→4I9/2) and (4F3/2→4I11/2), respectively. Fluorescence lifetime was recorded at 53.69 µs for the glass whereas the crystal was recorded at 43.62 µs. It was found that Nd3+ ions affected the physical, structural and optical properties of the glass and crystal samples.
Effect of Annealing Temperature on Platinum/YSZ Thin Film Fabricated Using RF and DC Magnetron Sputtering
Authors: Nurhamizah A.R. , Ibrahim Zuhairi , Muhammad Rosnita , Wahab Yussof , Sakrani Samsudi
Published: October 2017

This research aims to study the growth and the effect of annealing temperature on the structural properties of Platinum/YSZ/Platinum thin film. The thin films were prepared by RF and DC magnetron sputtering method utilized platinum as electrodes (anode and cathode) and YSZ as electrolyte. Two temperatures of annealing (400 and 600 °C) were conducted onto Platinum/YSZ/Platinum thin film for comparison in this study. Crystalline phase, microstructure and thickness of thin films were evaluated using X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FE-SEM) technique. Results show that Pt/YSZ/Pt thin film without post-annealing gives a better morphology and crystal phase.
Preparation of Indium Tin Oxide/Quaterthiophene Thin Film for Solution Processed Organic Device
Authors: Ngah Demon Siti Zulaikha , Ahmad Poad Nursaadah , Rahmat Noor Fadhilah , Bidin Noriah
Published: October 2017

Organic devices are advantageous in term of high carrier mobility, lightweight and flexibility. The solution processed method offers economic and efficient device fabrication in small laboratory scale. The α-quaterthiophene (α-4T) is an oligomer and a p-type organic semiconductor. In this study, pure α-4T and polylactide acid (PLA)/α-4T films were spin-coated on glass and indium tin oxide (ITO) substrates at low spin frequency. The hydrated films were left to dry at room temperature and later in vacuum oven. The α-4T microstructures changed when blended with the polymer. The roughness of the 180 nm ITO film was found to be 1 - 30 nm and the organic layer formed uneven thickness (max ~ 300 nm) thicker toward the edge. The preparation of spin coated organic thin film is the first step towards realizing solution processed organic device in electronic packaging.
Effect of Heat Treatment Condition on the Phase Formation of YBa2Cu3O7-δ Superconductor
Authors: Mohd Hapipi Nurhidayah , Shaari Abdul Halim , Awang Kechik Mohd Mustafa , Tan Kar Ban , Abd-Shukor Roslan , Mohd Suib Nurul Raihan , Chen Soo Kien
Published: October 2017

Polycrystalline samples with the nominal composition YBa2Cu3O7-δ (Y-123) were prepared using the co-precipitation method. The effect of the calcination process (single and multiple calcinations) on the samples was investigated by using the four-point temperature-resistance measurement, x-ray diffraction (XRD) and field-emission scanning electron microscope (FESEM). This study is divided into two parts. For the first part, the obtained oxalate powder underwent two calcination processes at 900 °C for 12 h and 900 °C for 24 h, respectively. Then, the powders were pressed into pellets and sintered at 920 °C for 15 h with oxygen flow during the entire heat treatment. In the second part, only one calcination process was undertaken at 900 °C for 24 h before the sintering process in oxygen flow at 920 °C for 15 h. From the XRD patterns, all of the peaks were indexed to the Y-123 phase showing that this superconducting phase was already formed after the first calcination. The volume fraction of Y-123 of the samples with single calcination process was higher compared to multiple calcination processes. From the temperature-resistance measurement, all the samples showed metallic behavior in the normal state and a superconducting transition to zero resistance. The superconducting transition temperature, Tc, for the samples prepared in a single calcination process is higher than that of the multiple calcination processes.
Phase Formation and Electrical Transport Properties of Nano-Sized SnO2 Added (Tl0.85Cr0.15)Sr2CaCu2O7-δ Superconductors
Authors: Kong Wei , Kong Ing , Awang Kechik Mohd Mustafa , Abd-Shukor Roslan
Published: October 2017

In this work, the effect of nano-sized SnO2 addition on the phase formation and electrical transport properties of (Tl0.85Cr0.15)Sr2CaCu2O7-δ (Tl-1212) superconductor was investigated. Thallium-based high temperature superconductor (HTS) with nominal starting composition (Tl0.85Cr0.15) Sr2CaCu2O7-δ was prepared using high purity oxide powders via solid state reaction method. Nano-sized SnO2 with 0.01 – 0.05 wt.% were added into Tl-1212 superconductors. The characteristic of the samples were determined by powder X-ray diffraction method (XRD), scanning electron microscopy (SEM), energy dispersive X-Ray analysis (EDX), electrical resistance measurements and transport critical current density measurements. Nano-sized SnO2 added (Tl0.85Cr0.15)Sr2CaCu2O7-δ showed Tc-zero between 93 and 95 K. All of the samples indicated a dominant phase of Tl-1212 with a minor phase of Tl-1201. The highest Jc (at 77 K) was shown by sample with 0.03 wt.% at 3260 mA/cm2. SnO2 has significantly enhanced the transport critical current density of Tl-1212 superconductor by acting as flux pinning centers. However, further addition of nano-sized SnO2 in Tl-1212 superconductor caused degradation in Jc. The SEM micrographs with energy dispersive X-Ray analysis (EDX) showed that SnO2 were well distributed in all the samples.
Phase Formation and Transport Critical Current Density of Tl2Ba2CaCu2O8 Superconductor with Nano Bi2O3
Authors: Dabaa I.M.O. , Abd-Shukor Roslan
Published: October 2017

The effect of nanosized Bi2O3 (150 nm) on the formation of the Tl2Ba2CaCu2O8 (Tl-2212) phase, transition temperature and transport critical current density has been studied. Samples with nominal starting composition Tl2Ba2CaCu2O8(Bi2O3)x (x = 0 to 0.5 wt. %) were prepared using the solid state reaction method. Most samples except x = 0.5 showed a mixed phase consisting of the Tl2Ba2CaCu2O8 and Tl2Ba2Ca2Cu3O10 (Tl-2223). The x = 0.5 sample showed a single Tl-2212 phase. However, the transition temperature, Tc of the x = 0.5 was very much suppressed (Tonset = 106 K, Tc zero 88 K). All samples showed random grain size and orientation, with partial melting and high porosity. The x = 0.1 mixed phase sample showed the highest transport critical current density of 285 mA/cm2 at liquid nitrogen temperature (78 K).
The Influence of Carbon Nanotubes Contents on Electrical and Flammability Properties of Poly(Lactic Acid)/Multiwalled Carbon Nanotubes Nanocomposites
Authors: Mat Desa Mohd Shaiful Zaidi , Hassan Azman , Arsad Agus
Published: October 2017

The effects of carboxylic functionalized multi-walled carbon nanotubes (CNT) contents on electrical and flammability properties of poly(lactic) acid/CNT nanocomposites were investigated. The PLA/CNT nanocomposites were prepared by melt-blending method, where the CNT contents were varied from 1 to 9 phr. From flammability properties analysis, nanocomposites with 9 phr CNT showed the highest limiting oxygen index (LOI) of 26.5 vol% as compared to 19.5 vol% of neat PLA. All nanocomposites with higher than 5 phr CNT contents also passed the V0 class of UL-94 vertical burning test rating. The direct current electrical test revealed that the electrical conductivity increases by approximately seven orders of magnitude from 2.19 × 10-11 S/m of neat PLA to 2.00 × 10-4 S/m for PLA/CNT nanocomposites with 5 phr CNT contents. The electrical conductivity of PLA/CNT continues to increase beyond 5 phr contents, with 2.26 × 10-3 S/m and 4.29 × 10-3 S/m respectively for 7 and 9 phr contents. The good dispersion of CNT leads to formation of electron conducting CNT networks throughout the insulating PLA matrix.
Iron Oxide Nanoparticles Derived from Mill Scale Waste as Potential Scavenging Agent in Dye Wastewater Treatment for Batik Industry
Authors: Abdul Rahim Arifin Azdiya Suhada , Ismail Ismayadi , Abdullah Abdul Halim , Shafiee Farah Nabilah , Nazlan Rodziah , Ibrahim Idza Riati
Published: October 2017

In this work, iron oxide were derived from millscale has been used as a potential scavenging agent in wastewater treatment due to its high adsorption capacity and its shorter sedimentation time during wastewater treatment. Iron oxide obtained from the magnetic separation technique was subjected to high energy ball milling (HEBM) at different milling time to produce different size of nanoparticles of iron oxide. X-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Scanning Trasmission Electron microscopy (STEM) were performed to study the morphological properties of the iron oxide nanoparticles. After HEBM, iron oxide nanoparticles was modified with Hexadecyltrimethylammonium Bromide (CTAB) to study the adsorption possibility of iron oxide nanoparticle modified with CTAB (Iron oxide– CTAB nanoparticles) in dye wastewater. The variation effect of particle size of derived Iron oxide– CTAB were studied. Permanent magnet was used to separate iron oxide nanoparticles from the solution. The clear part of the solution (treated wastewater) was filtered out and adsorption efficiency of Iron oxide– CTAB nanoparticles was measured using UV – Visible spectroscopy. Efficiency adsorption of iron oxide nanoparticles modified with CTAB greatly achieved above 99 % and the size of iron oxide nanoparticles affected its performance in dye wastewater treatment.
Ultrasonic Bulk Waves Measurements for Defect Detection of Composite Materials
Authors: Zainal Abidin Sham Nurul Wahida , Rohani Md Supar
Published: October 2017

The defect detection in composite material is important for its quality control where the hidden defect such as crack, corrosion, notch, holes, void and porosity can develop. In this paper, the ultrasonic bulk wave measurements of longitudinal and shear waves are used to identify defect in the multilayered composite material. This study employs pulse echo technique and utilized angle beam transducer. The composite material model investigated in this contribution are made of 24 mm and 12 mm thick Aluminium plates with a width of 100 mm and a length of 203 mm which are separated with an approximately 1 mm thick oil layer. A simulated defect is created in the composite test material by drilling a hole with 2.5 mm diameter and 3 mm depth on the bottom surface of the third layer material. Finding indicates that the defect is located at 53.39 mm from transducer and the percentage difference of the defect location compared to the calculation method is 7%. It indicates that the proposed method can be use to detect defect in multilayered composite material within 10% accuracy compared to the calculation method.
Ultrasonic B-Scan of Adhesive Bonded Thin Aluminum Sheet
Authors: Mhd Subre Azim Fikri , Rohani Md Supar
Published: October 2017

Ultrasonic inspection using b-scan (brightness scan) and its application for discontinuity and flaws detection were investigated. Brightness scan is one of the ultrasonic technique’s branches, it provides thorough image of the material which undergone inspection via density of the material where then depicted in different colour in conjunction with the acoustic impedance of the phase gone through by the sound wave. The sound wave generated with a piezoelectric transducer was propagated through aluminum wafer samples and were identified by the b-scan system. Its ability to detect flaw at certain depth which was introduced manually been examined. Experimental results show different brightness characteristic, depending on the adhesive treatments, type of material and medium when the waves pass through in each sample. Brightness scan system was proven to be reliable non-destructive testing method in ultrasonic for inspection of structural bonded materials.
Completion of Successful Multistage Sliding Sleeve Fracpack in the Campos Basin
Authors: Correa Rubens , Cova Carolina Latini
Published: October 2017

The Campos basin is offshore Brazil in deep water and has unconsolidated formation characteristics. As such, wells located in this area are usually completed using sand control techniques. In the Roncador field, a vertical well with multiple pay intervals required a sand control solution for each zone. The primary challenge was to complete the total gross interval using a cost-effective sand control method that allowed selectively stimulating five zones and producing without solids.

The largest multipurpose oilfield stimulation vessel in the world was assigned to perform its first deepwater offshore multistage fracpack treatment, which is a combination of fracturing stimulation and gravel packing. The five individual treatment stages were successfully performed as designed using multitrip sliding sleeves, which would later allow selective production of the zones. This allowed the operator to selectively isolate the intervals during completion of each one. In addition, this was the first time using a new sand-storage system and blender without a tube, which provided better reliability and a shorter response time.

The operator and service providers collaborated to design the multistage well completion, providing both sand control and stimulation. The treatment plan was performed by this large modern service vessel without any reports of incidents or lost time. Additionally, all operational data were transmitted in real time to onshore operator and service company facilities. The five-stage treatment plan was performed in only 28 days, representing an estimated savings of 15 rig days for the operator compared to completions using a conventional treatment method.

This paper reviews a deepwater Campos basin well that has multiple pays and potential sand production. The operator and service provider applied new completion technology for stimulation/sand control, which provided several advantages, including a significant reduction in required rig days. This was the first opportunity for the large stimulation vessel to conduct such an operation, and the performance of both the equipment and service crew was excellent.
How to Improve the Use of PDG Data on Injector Wells: A Temperature Build-Up Approach
Authors: da Silva Victor Costa , Glitz Karime Louise Zenedin
Published: October 2017

One of the main activities of a reservoir engineer is to manage the production and injection of fluids in a reservoir. By managing the production and injection it is possible to react to the breakthrough of the injected fluids and control the rate at which BSW and GOR increase in the production wells. In wells completed in more than one target zone the reservoir management can be done by restraining or just closing the interval through which the injected fluids are inflowing. However to identify the interval through which the water or gas is produced in this kind of well is not an easy task, being the track of the paths through which the injected fluids flow in the reservoir (as well as in the neighborhood of the well) the main challenge of the reservoir management.

In this paper a set of data of different wells of a Santos Basin Pre-salt reservoir is presented. Intelligent completions with more than one target zone are installed in these wells and the temperature data of each zone are analyzed. Simplified analytical models are employed to describe the various regime flows observed in these wells, thus providing some insights in order to characterize the flow.

Temperature data of production and injection wells are analyzed in different scenarios were the gas and/or water saturation modifies near the wells. The main hypothesis adopted in this work is that the change in temperature behavior is associated to the modification of the saturation of the different fluids in the reservoir.

This paper aims at estimating the length of the modified saturation region near the injection well by assuming that the thermal diffusion is predominant. By doing so the problem is described by the energy balance equation and the boundary and initial conditions depends on the condition of the well (if it is operating or closed).

This methodology is further extended to analyze the change of fluids saturation near production wells in order to provide some insight about the breakthrough of injected fluids.

By comparing the theoretical response of the methodology presented in this paper to that observed in the wells it is possible to make some conclusions about (i) the injection profile in wells where the isolation between the zones in the well's neighborhood was lost during the stimulation of the formation and (ii) about the distribution of the injected fluid in the reservoir near the wells, whose isolation between zones was not lost during the stimulation.
A Physical Model for Scale Growth during the Dynamic Tube Blocking Test
Authors: Santos H. F. L , Castro B. B. , Bloch M. , Martins A. L. , Schlüter H. E. P. , Júnior M. F. S. , Jacinto C. M. C. , Rosário F. F.
Published: October 2017

A physical model for scale growth in the Dynamic Tube Blocking Test (TBT) is presented aiming at the determination of the first layer formation time and the scale growing rate. The proposed model has been applied to 38 experimental results, each one with a different water composition. The fluid compositions were selected to represent the majority of the fluids found in typical Brazilian oil wells. For the application of this model, no differential pressure was considered before pumping. Additionally, the pressure rising time was not taken into account in the calculation of the first layer formation time. The model showed excellent fitting to the experimental data, with correlation coefficients superior to 0.98 for most data. Furthermore, the results of the scale growing rate were compatible to the results from other experiments, utilizing: rotating cage; static reactors; and full scale Inflow Control Valves (ICVs). Furthermore, on a scientific perspective, the model can also be used for the development of scale growing models as a function of pressure, temperature, composition.
Ultra Deepwater Salt Zone Cementing in Gulf of Mexico Wells
Authors: Vallejo V. , Olivares A. , Salinas D. , Rojas R. Giron
Published: October 2017

One of the last exploratory frontiers offshore, where some of the biggest reservoirs have been found in late days, are the ultra deepwater areas of the Gulf of Mexico, in the Mexican side. Several methods and lessons learnt have been produced during the Exploratory Campaign of these waters, becoming the massive salt formations, one of the major challenges faced, not only for drilling methods and techniques, but for zonal isolation in general terms, related to cementing operations.

Cementing jobs executed in salt environments require cement slurries with specific concentrations of salt in order to avoid the acceleration/retarder effect of thickening time on the cement slurry due to formation salt incorporated during fluids placement in the annular space, and to avoid the dissolution of natural salt formation. Likewise compressive strength development must be capable of mitigating the effects of salt cuttings on the casing that isolates the zone to ensure the integrity of the section.

Salt is commonly classified as: Magnesium salts – regular movementHalite – low movementCarbonates – without movement

This paper includes lab tests to determine the physical and chemical properties of cement slurries with different concentrations of sodium chloride (NaCl) and potassium chloride (KCl). A deep analysis was performed with these slurries when in contact with salt formations, determining the dissolution effect of salt in cement slurries. Lab tests were performed with Halite samples from ultradeepwater wells in the Northern Region of the Gulf of Mexico.
Study of the Mechanical Properties and Fracture Morphology of Niobium Microalloyed 80 ksi Class Thick Plates Produced by Controlled Rolling Followed by Accelerated Cooling
Authors: Viana R. T. , Gorni A. A. , da Silveira J.H.D. , Camey K. , de Faria R. J.
Published: October 2017

This paper describes the first production trials of 80 ksi class thermomechanically controlled processing (TMCP) thick plates at the new Gerdau Ouro Branco plate mill. These trials were very successful, as the product fully satisfied the mechanical properties requirements for such grade, enabling the start of commercial delivery of this material. In addition, experience gained in this process will promote further technological improvement of this class of products, as well more sophisticated plates. The occurrence of separations in the fractured surface of Charpy specimens was considered with detail.
Deployment of Electro-Mechanical Cutting Tool on Intelligent Coiled Tubing for Horizontal Wells
Authors: Carvalho Ricardo de Paula , Barros Robledo Wakin , Gastaldo Felipe Toloi , Amorim Alexandre , Moreira Jean Narlon , Gomes Deylla Silva
Published: October 2017

This paper will describe the merits of deploying the Electro-mechanical cutting tool with the Intelligent Coiled Tubing, the advantage of this cutting method compared to ballistic, chemicals and other mechanical devices in terms of precision, time saving, safety and real time cutting assurance, as well as the added advantages generated by the Intelligent Coiled Tubing by itself on the overall operation.

The recent introduction of Intelligent Coiled Tubing services, equipped with real time downhole tools communication and power down capabilities within the market, has made possible the deployment of the electro-mechanical multiple cutting tool on Coiled Tubing. The emergence of this technology, allows the cutting tool to perform operations in previously unreachable environments, taking advantage of the Intelligent Coiled Tubing high level of efficiency and reliability, which historically was a concern when running wire line in horizontal wells.

With an increase in Plug and Abandonment projects expected, especially in deep water environments, new challenges will arise when it comes to cutting and retrieving completions. The electro-mechanical cutters have proven in recent years to be an extremely reliable, efficient, and a safe method to perform cutting operations in tubulars, sand screens, as well as releasing packers. The paper will present a case history detailing the methodology, and the involved pre-job planning, deployment, risk management& modeling, demonstrating the completeness of this solution and highlighting its reliability.

The paper will show how the combination of the Intelligent Coiled Tubing combined with the Electro-Mechanical Cutting device can render the usage of ballistic, chemical and other mechanical devices as unnecessary in challenging environments that rely on conventional Coiled Tubing
Technical-Economic Evaluation of Microfiltration Polymeric Membranes as Pretreatment of Offshore Sulfate Removal Units
Authors: Santos Tais Neno dos , Yokoyama Lidia , Lage Gustavo Garios
Published: October 2017

A technical-economic research was done evaluating microfiltration polymeric membranes and cartridge filters as pretreatment of Sulfate Removal Units (SRU). These units were installed in a Stationary Production Unit (SPU) to reduce the concentration of sulfate from seawater (injection water in Enhanced Oil Recovery). The use of seawater with low sulfate in enhanced oil recovery reduces the risk of sulfate deposits during the oil production. Ten companies from different nationalities involved in the industrial water treatment and manufacturing of polymeric membranes sector, have contributed to this comparative research (only a preliminary stage of the future study with qualitative and quantitative analyses). This paper shows that polymeric microfiltration is more advantageous because reduce operational costs and microbiological contamination resulting in a lower risk of biofouling. It also improves the quality of treated water, increases the operational stability and availability of the injection water, extending the lifetime of the nanofiltration polymeric membranes.
Production Experience of ICD/AICD for Heavy Oil at Peregrino Field
Authors: Araujo Susana Vasconcelos , Bolliger Alexandre , Pettan Cássio , Erlandsen Sigurd Myge , Leitão Ivan
Published: October 2017

The Peregrino Field is an accumulation of 13-16° API oil in the Carapebus Formation in the Campos Basin and is thereby one of the heaviest oil offshore developments in Brazil. The field was discovered in 1994 and in 2007 Statoil became a Peregrino partner followed by Peregrino operatorship in 2008. The field has been in production since 2011 by using two well head drilling platforms and one FPSO in water depth ranging between 95 to 135 m. There are 45 production and injection wells drilled so far and 15 remaining slots on the platforms. The Peregrino recovery mechanism is mainly based on reservoir depletion and rock compaction combined with aquifer pressure support and produced water reinjection in the water and oil zones.

The viscosity difference between oil and water at Peregrino gives an unfavorable mobility ratio, and water flows with a higher velocity than the oil. Any means to limit the water flow from the wells may enable an optimization of oil production. In 2013, a technology qualification program was conducted to qualify both Inflow Control Devices (ICD) and Autonomous Inflow Control Devices (AICD) technologies for use at Peregrino. Since then 2 wells have been equipped with ICDs and 7 with AICDs. The production experience from those ICD/AICD wells shows that the device is best suited in areas with good pressure support, high productivity index (PI) and heterogeneous reservoir.

The paper will cover a comprehensive evaluation done for the ICD/AICD wells in Peregrino focusing on subsurface data challenges and performance predictions.