bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanomechanical Properties of Vimentin Intermediate Filament
Authors: Wong K.L. , Ngan A.H.W. , Shum D.K.Y. , Lu W.W.
Published: February 2012

Vimentin intermediate filament (IF) is one of the major proteins which built the cytoskeleton network alongside with the microtubule and actin filament. Though it was known that the vimentin IF network plays an important role in the mechanical behaviours of cells, it is surprised that its mechanical behaviours are not fully understood to date. The aim of this paper is to study the nanomechanical properties of vimentin IF using the atomic force spectroscopy (AFM) which allows the manipulation and force spectroscopy of filaments. The vimentin intermediate filaments were attached to the APTES (3-aminopropyltriethoxy) functionalized mica which offered better adhesive force. In the force spectroscopy study, the AFM tip was allowed to clamp filaments and then retraced. The force-displacement curve of the process was obtained for analysis. The curves can be grouped into two major groups – sewtooth and plateau. The appearance of sewtooth was more frequent than the plateau. The sudden force changes (jumps from higher to lower force) in sewtooth and plateau curves were also analyzed. It was shown that the partial ruptures which denoted by the jumps favoured small force (~100 pN) and short range (separation of jumps below 25 nm). This result also demonstrated the probability of different modes of partial IF ruptures.
Synthesis of Self-Aligned Titanium Oxide Nanotube Arrays in Ammonium Fluoride-Ethylene Glycol Electrolytes with Different Water Contents
Authors: Thongyoy Sasitorn , Aeimbhu Areeya
Published: February 2012

The aim of this research is to fabricate of TiO2 nanotube arrays by potentiostatic anodisation process on titanium sheets. Anodisation is carried out under various applied potentials ranging from 20 to 30 volts for 1-3 hours at room temperature. Anodised were conducted in 1-4 wt% NH4F, water-based electrolyte and ethylene glycol-based electrolyte. The morphology of the anodised surfaces were characterised by scanning electron microscopy. When titanium sheets were anodised in various conditions, surface morphology of anodised titanium change remarkably with the changing of applied voltages, chemical composition of the electrolyte and anodisation time. The results of the present work show that the highly ordered and uniformly distributed TiO2 nanotubes on titanium substrate can be fabricated by using mixtures of NH4F, ethylene glycol and water with appropriate conditions. Moreover, the anodisation potential and the water content play significant roles in the formation of TiO2 nanotube with different inner tube diameters. The length of TiO2 nanotube was controlled by anodisation time.
A Theoretical Framework for Healthcare Innovation Management Using Wiki Based Digital Ecosystem
Authors: Fasihuddin Heba , Skinner Geoff , Athauda Rukshan
Published: February 2012

Information Technology innovations have strongly affected today’s businesses and the way we work. This effect involves different industries, and the healthcare industry is one of them. Various healthcare information systems have been introduced to manage and share patient records and information. However, based on the reviewed literatures, the healthcare knowledge management system does not have the same focus and attention. It is found that there is no system that is able to manage the tacit healthcare knowledge and innovation. As a result, this paper aims to introduce a theoretical framework that enables healthcare tacit knowledge management and global sharing. Digital Ecosystem is found to be the most suitable technology to achieve this aim; specifically with the wiki environment as it is most suitable for the healthcare industry requirements.
Application of Lignin from Oil Palm Biomass as a Fluid Lost Reducer
Authors: Taleb Fayyadh Faisal Salehbin , Ibrahim Mohamad Nasir Mohamad
Published: February 2012

This paperexplainedthe use ofsolventnon-reactive technique with catalyst based on solution polymerization. The polymerization of Lignin as a raw material could produce a new compound as Lignin Graft Copolymer (LGC) which can be used in oilfield operation to solve fluid loss problems. In this technique, Lignin polymerize with superabsorbent polymer (SAP) using different parameters such as; heat, staring, time, and amount of catalyst. The Lignin was extracted from soda pulping process of Oil Palm Empty Fruit Bunch (OPEFB) long fibers. Lignin functional groups were characterized using Fourier TransformInfrared(FT-IR) spectroscopy.This product required further laboratory experiments to enhance its industrial applicability as a drilling fluid reducer.
Effect of Zr Addition on Mechanical Properties of Ti-Nb-Zr Alloys for Biomedical Applications
Authors: Sungtong W. , Khantachawana Anak
Published: February 2012

Artificial bone implant is concerned to improve their substantial features such as biocompatibility and mechanical properties. Ti-Nb alloys were considered to be one of the competitive materials because of their good biocompatibility and pseudoelasticity. In a present work, the effect of Zr addition as a third element on mechanical properties and pseudoelasticity of Ti-Nb alloys with Nb-content of 22-23at% were investigated by using cycling tests. The alloy ingots were fabricated by an arc melting method. The ingots were homogenization treated at 1273 K for 3.6ks followed by cold-rolled to a reduction ratio of 90% in thickness. All specimens were heat-treated at 873 K and some of them were aging treated at temperature ranging from 573 to 673 K after heat-treatment. Pseudoelasticity and mechanical behavior were evaluated by cycling test at room temperature. The results suggested that psuedoelasticity was confirmed in specimens without aging treatment irrespective of alloy compositions. Maximum recovery strain recovery increases with increasing Zr content. From all information acquired, it can be concluded that Ti-22Nb-(3-4)Zr(at.%) and Ti-23Nb-(2-3)Zr(at.%) alloys are the most optimum for artificial bone.
Laboratory Study on a Novel Self-Diverting Gel Acid System Thickener
Authors: Zhu Qi , Liu Ping Li , Zhao Li Qiang , Chen Ji Mei , Cao Yan Feng
Published: February 2012

Acid stimulation of carbonate formations using hydrochloric (HCl) acid-based systems to improve hydrocarbon production or water injection has been a common practice. The challenge of achieving full zonal coverage with the stimulation fluid still persists. This task is even more difficult in highly slanted layered, naturally fractured reservoirs exhibiting high permeability and porosity contrast. During acid stimulation treatments, the fluid has a natural tendency to take the path of least resistance, penetrating layers with the highest porosity and permeability while little or no acid is injected into lower-quality zones. Excessive fluid loss to these high-quality thief zones results in a nonhomogenous distribution of stimulation fluids across the targeted interval. This leaves neighboring lower-quality zones unstimulated, preventing them from reaching their maximum potential. In this paper, a gel acid system composing hydrophobically modified PAM and viscoelastic surfactant (SA-16) as a novel self-diverting acidizing system was introduced, which can lower acid loss. This novel system was evaluated on temperature stability, viscosity test, gel breaken and acid-rock kinetics test supported by laboratory study. Its favorably high viscosity, ideal gel breaken, upstanding temperature resistance and other prior properties can be applied to acid stimulation.
The Effect of Denser Material than Air in Front of Clinical Radiotherapy X-Ray Beam
Authors: Fayaz Vahid , Amirabadi Morteza
Published: February 2012

scatter photon produced during radiationtherapy with high energy photons is the main source of unwanted out-of-field and superficial received doses of patients.Surface buildup dose is dependent on electron contamination primarily from the unblocked view of the flattening filter and secondarily from air and collimation systems .We performed a comprehensive set of surface and buildup dose measurements with a thin window parallel-plate (PPC-40) chamber to examine effects of attenuating media in front of 6 MV X ray. To evaluate the impact of beam segmentation on buildup dose, measurements were performed with 10 × 10 cm2 fields, Measurements were performed in Solid Water using parallel plate chambers and diode for a 6 MV X-ray beam.
Future of Wind Energy in Iran
Authors: Moharrampour Mahdi , Asadi Mohammad Reza , Abdollahian Heidar
Published: February 2012

The activities in field of renewable energy in Iran are focused on scientific and research aspect. And research part is aimed at reduction of capital required for exploitation of related resources. The second step is to work research results into scientific dimension of this field for practical means, i.e. establishing electricity power plants. Due to recent advancements in wind energy, many inventors in the country have become interested in investing in this type of energy. At the moment, projects assuming 130 MW of wind power plants are underway. Of which, 25 MW is operational. The project of Iran's renewable energy aims to accelerate the sustainable development of wind energy through investment and removal of barriers. This preparatory project is funded by the Global Environment Facility (GEF) and will provide for a number of international and national consultant missions and studies. Once the studies are concluded, a project to develop 25MW of wind energy in the Manjil region of Gilan (N-Iran) will be prepared. It will be consistent with the national development framework and objectives and form part of 100MW of wind-powered energy, Which is expected to be developed under the government's third 5-year national development plan. (started 21 march 2000)
Marine Environment Problems Caused by the Development of the Coastal Cities and the Solutions for them
Authors: Shen Xu Hong , Xiao Fei Peng
Published: February 2012

Coastal cities in China show their strong economic competitiveness in the economic development of China and they have become one of the regions where the economy grows dynamically. Contaminated area near the coastal cities is expanding and the marine environment has been damaged seriously. The frequency of marine disasters is increasing and the marine disaster has obstructed the development of the coastal cities. The disasters appeared from the development of the industry, agriculture and fisheries of the coastal cities directly and indirectly from the planning of the government without consultation and cooperation. The confusion of property affiliation leads to the diversification of property ownership and the resources can not be used and protected efficiently. This paper lists the problems that caused by the rapid development of the coastal cities. Finally the suggestions are proposed to improve this situation, which are significant for the policies in socio-economic development, resource utilization and environmental protection.
Research on the Influence of Solar Radiation, Sky Background Radiation and Sea Surface Emission to Infrared Search
Authors: Chen Yu , Hu Yun An , Zhao Yong Tao , Xie Yong Xing , Cheng Chun Hua
Published: February 2012

Sea background radiation is influenced by solar radiation, sky background radiation and sea surface emission radiation. On the basis of studying the simple sea radiation model, analyze the influence of atmospheric transmittance and sea background radiation to infrared detector, emphasis on influence of solar, sky and sea surface emission radiation to infrared search in analyze Sea background radiation, emphasis on influence of aerosol to infrared search under troposphere in analyze atmospheric transmittance.
Review of Renewable Energy in Iran
Authors: Asadi Mohammad Reza , Torgadri Mahmoud Baghban , Moharrampour Mahdi
Published: February 2012

Increasing in consumption of petroleum, population, environmental problems, diminishingly fossil sources and world trend to energy technology respect to environmental safety and renewable energy are some reasons for most countries to use and investigate on renewable energy. In this regard this paper presents the state of geothermal, wind and biomass energy in Iran. Results indicate that Iran has substantial geothermal potential, specifically in the Sabalan (NW-Iran) and Damavand (N-Iran) regions that are considerate prospects for electric power generation and direct uses. Due to recent advancements in wind energy, many inventors in the country have become interested in investing in this type of energy. At the moment, projects assuming 130 MW of wind power plants are underway. Of which, 25 MW is operational. Results of this study shows that the major biomass resources in Iran are agricultural solid wastes (%59), animal wastes (%28), corrupting waste materials (%11), and industrial waste waters (%2). According to statistical data, the potential biomass energy in Iran is equal to 15 million ton of crude oil which will be estimated about %13 of annual Iranian crude oil sale.
SnO2/Graphene Nanocomposite as an Enhanced Anode Material for Lithium Ion Batteries
Authors: Wang Hai Teng , He Da Wei , Wang Yong Sheng , Wu Hong Peng , Wang Ji Gang
Published: February 2012

We report the fabrication of a tin nanoparticles coated anode in graphene (SnO2 /graphene) for lithium-ion batteries. As an anode material for Li ion batteries, it has 806mAhg-1 and 683mAhg-1 capacities for the first discharge and charge, respectively, which is more than the theoretical capacity of tin oxide, and has good capacity retention with a capacity of 606mAhg-1 after 30 cycles.
Preparation and Characterization of Al-Mg-B Thin Films by Magnetron Sputtering
Authors: Liu Wen , Meng Qing Sen , Miao Yang , Chen Feng Hua , Hu Li Fang
Published: February 2012

Hard and superlight thin films laminated with boron carbide have been proposed as candidates for strategic use such as armor materials in military and space applications. We prepared Al-Mg-B films by sputter deposition on Si (100) substrates with one AlMgB14 target. The films were characterized by X-ray diffraction, atomic force microscope, GD-OES spectroscopy. The results show that films of AlMgB with different compositions have been deposited by changing the target power and deposition temperature.The influences of substrate temperature and sputtering power on the quality of the films are discussed.
Assessing the Effect of Nano Biphasic Calcium Phosphate on Acute Alveolar Bone Defects in Beagle Dogs Using Micro-Computed Tomography Imaging
Authors: Wang Lan Lei , Hou He Ying , Zhang Jian Xin , Sun Zong Mei , Yang Pi Shan , Liao Yun Mao
Published: February 2012

The aim of the present study was to assess the effect of nano-biphasic calcium phosphate (nanoBCP) scaffolds on acute alveolar bone defects in beagle dogs by micro-computed tomographic imaging (μCT). Alveolar bone defects were surgically created bilaterally at the buccal aspects of the upper second premolars in four beagle dogs. After root conditioning with ethylenediaminetetraacetate (EDTA), nanoBCP was randomly filled in the defects and nothing was put into the contralateral defects as controls. Dogs were killed at the 24th weeks. Specimens were scanned and reconstructed though μCT. The results revealed that much new alveolar bone formed in the defects in the nanoBCP groups while no new alveolar bone formed in the controls. The present results indicate that PBCP may enhance alveolar bone regeneration in acute-type labial dehiscence defects.
Fabrication of ZnO Waveguide Films Deposited on Sapphire and MgO Substrates by RF Magnetron Sputtering
Authors: Wang Feng Xiang , Qi Jun He , Lu Fei , Qin Xi Feng , Liu Zhao Hong , Yang Guang , Chen Zhi Hua , Song Hong Lian
Published: February 2012

ZnO waveguide films were fabricated on sapphire (001) and MgO (100) substrates by the radiofrequency (RF) magnetron sputtering technology using ZnO ceramic as the target. Properties of the films were investigated by prism coupling method, X-ray diffraction (XRD) and Rutherford backscattering spectrometry (RBS). The results demonstrated that the ZnO nano-films have planar waveguide structure and have nearly stoichiometric composition with c-axis preferred orientation growth. The growth rates of the films were slightly influenced by the substrates. The effective refractive indices of the films were smaller than the bulk material and were affected by substrates. The relationships between the average grain sizes, substrates, and film thickness were analyzed.
Assembling of 12-Tungstophosphoric Acid into Amino-Modified SBA-15 and its Catalytic Performance
Authors: Guo Hong Qi , Yan Gong , Chen Ming Qing , Liu Shi Rong
Published: February 2012

12-tungstophosphoric acid was supported on amine-modified SBA-15 by impregnation. The structure and properties of the catalyst were characterized by FT-IR spectroscopy, X-ray diffraction, N2 adsorption-desorption, TEM,Raman spectra and NH3–TPD technology.the result confirmed the mesostructure for SBA-15 and the Keggin structure of the heteropolyanions was preserved. The tungstophosphoric acid can disperse in the pore of the support SBA-15/NH2, but the acidity of the catalyst reduced. The catalytic activities of the catalysts were evaluated for the esterification reaction of ethyl acetoacetate and ethylene glycol .and the catalysts supported on amine-modified SBA-15 show excellent reusability and selectivity.
Interface Effect on Properties of Fe/BaTiO3/Fe Junction
Authors: Deng Lei , Chen Dong , Zhu Yin Lian , Ma Xiu Liang
Published: February 2012

First principle calculations have been performed to study the interface structure effect on physical properties of the Fe/BaTiO3/Fe junction. It is identified that Fe on top of the TiO2- terminated plane with two Fe atoms adsorbed on the two O top sites is the most stable interface. The interface structure is found to affect the ferroelectric behavior of BaTiO3 layer. With BaO-terminated interface, BaTiO3 shows larger Ti-O distance compared with TiO2-teminated interface. In addition, there is a sizable difference in magnetic moments on interfacial atoms at the two interfaces.
Compound Extraction and Component Analysis on Volatile Oil of Artemisia Argyi
Authors: Pan Xiao Hui , Wang Jin Mei , Wu Tie Cheng , Sun Yi Fan
Published: February 2012

Abstract: In order to prepare natural anti-mosquito agent, the volatile oil was extracted from artemisia argyi by three-step of water extraction, steam distillation and organic solvent extraction. Three factors have been optimized. They were material/liquid ratio, distillation time and crushing particle size having influence on the extraction efficiency. The experimental results showed as: the optimum extraction process was that material/liquid ratio for 1:20, distillation time for 4 hours and crashing particle size for 40 meshes. At optimized extraction process condition, the extraction efficiency was 0.71%. Chemical constituents were determined by gas chromatography-mass spectrometry apparatus (GC-MS). They were mainly single terpenoids and its derivatives, including monocylic single terpenoids and 2-ring single terpenoids. Primary components were eucalyptol, camphor, camphene, borneol and so on. This provided good foundation for preparation of anti-mosquito and anti-insect agent.
Effect of Preparation Method on Film Structure and Thermal Stability of Me/MeN/Me (Me = Al, Ti) Multilayer Thin Films
Authors: Hong Zhang Lian , Xu Jian Feng , Zhou Shi Feng , Long Zhong , Xiao Hong , Li Fang Fang , Liu Ke Zhao
Published: February 2012

Me/MeN/Me (Me=Al, Ti ) multilayer thin films were deposited on silicon substrates by a multi-arc ion plating method (MAIP) and successive magnetron sputtering method (MS) respectively. The as-prepared and heat-treated films were characterized by scanning electron microscope (SEM) and auger electron spectra (AES). The results revealed that MS method has an advantage over MAIP method to prepare the Al/AlN/Ti submicron thin films which have high density, clear interface and smooth surface. In addition, the present study indicated that both the deposition sequence and mid-layer composition have a significant effect on the thermal stability. After heat-treatment at 500 oC for 10 min, the Al/AlN/Ti multilayer film prepared by the MS method has good thermal stability without surface crack or surface flaking. Furthermore, significant diffusion of oxygen element and nitrogen element within the multilayer interface was observed by the AES measurement. It is believed that the element diffusion in the multilayer interface plays an important role in the binding strength of multilayer interface.
Weak-Light Readout Collection on the Quantum Effect Photoelectric Sensor
Authors: Zhang S.H. , Wang M.J. , Guo Fang Min
Published: February 2012

The weak-light characteristics of the GaAs/InGaAs quantum effect photoelectric sensor are presented. In order to explore its higher sensitive application because of higher quantum efficiency, a readout integrated circuit (ROIC) of the capacitor feedback transimpendance amplifier (CTIA) was designed to deal with voltage response of novel sensor. The readout circuit integration was designed to match 2×8 the photoelectric sensor array. A 633nm laser beam shot to the window of sensor with radiation intensity 2nW the readout response voltage was 225mV and 4.5E +07V /W responsivity at 120K and 44.8μs integration time when biased voltage up to -3V. Even under 0.5nw shooting,we still can see the high sensitivity.
Theoretical Analysis of the DOS and Band Structural Properties of Ti1-XSnxO2 Solid Solutions
Authors: Lin Zhi Dong , Song Wen Long , Zheng Ju Cheng
Published: February 2012

The band structure and density of states (DOS) of Ti1-xSnxO2 solid solutions with x=0, 1/8, 1/4, 1/2 and 1 were investigated by means of the first-principle calculations based on density functional theory. The result indicated that band gap and Fermi level of TiO2-SnO2 vary continuously from those of pure TiO2 to those of Sn content increasing. In addition, the DOS moves towards low energy and the bang gap is broadened with growing value of x. The wide band gap and the low density of the states in the conduction band result in the enhancement of photoactivity in Ti1-xSnxO2.
Anatase TiO2 Colloids Derived from the Peptization of TiO2 Precipitates with CF3COOH and their Photocatalytic Activities
Authors: Yuan Su Jun , Li Yao Gang , Zhang Qing Hong , Wang Hong Zhi
Published: February 2012

The highly dispersed TiO2 sols composed of anatase crystallites (ca.5 nm) were prepared by peptization of amorphous precipitates with trifluoroactic acid (TFA) during the synthesis. The size and crystallinity of the particles were tuned by the subsequent hydrothermal treatment. The prepared TiO2 nanocrystals were characterized by X-ray diffraction and transmission electron microscopy (TEM). The TEM results indicated that the growth of the crystallites could be inhibited by the increasing addition of TFA and the average sizes of TiO2 nanocrystals were all ultrafine. The degradation of phenol over the nanocrystals after calcination at 500 °C was investigated. The photocatalytic results showed that the sample with a high addition of TFA obtained a better photocatalytic property than that of the commercial TiO2
Synthesis, Characterization and Fluorescent Properties of Complex Fluoride BaNiF4: Ce3+
Authors: Tian Hai Yan , Shen Hai Yun , Yang Qiu Hua , Wang Xue Juan
Published: February 2012

The complex fluoride BaNiF4:Ce3+ was synthesized by reflux method using ethylene glycol as reaction solvent at its boiling point temperature. The sample was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and fluorescence spectrophotometer. The results indicated that the mean particle diameter of BaNiF4:Ce3+ was 53.8 nm. Only adsorption oxygen (α oxygen) existed on the surface of BaNiF4: Ce3+ and the content of surface oxygen was ≤5%. The maximum emission peak of BaNiF4:Ce3+ was 350 nm in its luminescent spectrum, and emission band of Ce3+ belonged to 5d→4f transition.
Deactivation Mechanism of SCR Catalyst Based on Nano-ZrO2
Authors: Liu Rong , Yang Zhi Qin , Guan Hao
Published: February 2012

A catalyst, 8%Fe-10%MnOx-CeO2/ZrO2, was prepared and applied for selective catalytic reduction of NO with NH3 at low temperature. The effects of SO2 and H2O on the catalyst were studied. The results showed that in the absence of SO2 and H2O, the catalyst 8%Fe-10%MnOx-CeO2/ZrO2 has good activity and stability. The presence of SO2 and H2O make the catalyst deactivate, and the activity can be recovered mostly by heating at 400°C. Properties of the catalyst on different reaction stages were characterized by FT-IR to study the inactivation mechanism of the catalyst. The results showed that the catalyst deactivation is due to the deposition of ammonium sulfate on the catalyst and the sulphation of the metal oxides of the catalyst.
Study of the Manufacture about Nanogenerators and their Performance
Authors: Zhang Can Can , Sheng Jian Guo , Zeng Ping
Published: February 2012

With the development of science and technology, the smaller sizes generator, the more attention by people. The main purpose of this article is to manufacture three-phase nanogenerator and piezoelectric nanogenerator under vibration, and their working principle are introduced and their performances are studied. The results show that, using the present nanomaterials, three-phase nanogenerator and piezoelectric nanogenerator can be prepared. In ambient vibration condition, piezoelectric materials produce larger rated current and voltage. However, copper laps cutting magnetic line of force produce less rated current and voltage. So the piezoelectric nanogenerator can be separately used to supply power. It may produce higher voltage, current and power if three-phase nanogenerator and piezoelectric nanogenerator in series-parallel connection, and there is commercial value.
Electrochromic Properties of the Multicolored Polyaniline Nanofilms
Authors: Bai Ying , Li Xin , Du Jian Xin
Published: February 2012

In this paper, electrochemical polymerization method was used to prepare electrochromic PANI films with different thicknesses via changing the polymerization time. It is found that the obtained PANI films are uniform and have good adherence with the ITO bases. Scanning electron microscope (SEM) images further show that the obtained films exhibited the tremella like lamellar structures with the diameter of each leaf about 100nm and the thickness of about 20nm at polymerization time of 8min. Optical electronic tests indicated that the films showed a gradient color variation from pale yellow, light yellow to green, blue-green, blue and dark blue among -0.2V and 1.0V. Furthermore, the color saturation increased and the hues became more abundant as polymerization time extended. The optical contrast ratios (ΔT) firstly increased to the maximum of 35% and then decreased, while the response time became longer. The results illustrate that the different shades of color are probably obtained through electrochemical polymerization method, which is important for the preparation of RGB full color system.
Tooth Tissue Engineering: Potential and Pitfalls
Authors: Gupta Sweta , Sharma Chhavi , Dinda Amit Kumar , Ray Amiya K. , Mishra Narayan C.
Published: February 2012

All over the world a large number of people suffer from tooth diseases like dental caries, tooth abscess, and plaques. Tooth loss or damage, which occurs frequently in our society are generally repaired by applying several conventional methods, such as root-canal treatment, direct pulp capping and dental implants. These methods are quite painful, create damage to the surrounding tooth tissues and also may at times have adverse side-effects. The limitations of the conventional methods can be overcome by applying the concept of tooth tissue engineering. Tooth tissue engineering is the application of biosciences and engineering to regenerate a biofunctional tooth, which can be used to replace the missing tooth or repair the damaged tooth. Tissue engineering involves three key elements - cell, scaffold and growth factors, which interact with each other to regenerate a specific tissue. The success of tissue engineering depends on the proper selection of these three key elements and understanding the interactions among them. To bring us close to the realization of a tissue-engineered tooth, immense progress is going on in understanding how tooth is first developed, and there is a good advancement in tooth regeneration. In this review, “tooth tissue engineering” will be discussed, along with the recent advancements and challenges in bring a biofunctional tooth from laboratory out into clinical use.
Finite Element Modelling of Rheological Property of Curing PMMA Bone Cement. Part 1 - Effect of Prosthesis Insertion Velocity
Authors: Rahman M.M. , Olabi Abdul Ghani , Hashmi M.S.J.
Published: February 2012

PMMA (Polymethyl methacrylate) bone cement is currently the only material used for anchoring cemented arthroplasties to contiguous bones. The aim of this work is to model the flow of bone cement through porous cancellous bone to study the degree of penetration in total hip replacement using FIDAP simulation software. Two different viscosity models have been used (a) power law with constant consistency index and power law index less than 1 for pseudoplastic behaviour of Simplex P® and Zimmer bone cement; (b) FORTRAN subroutine for time dependent rheopectic behaviour of CMW3 and Zimmer bone cement. For each type of bone cement the effect of prosthesis insertion velocity have been investigated under four different values 5, 10, 15 and 20 mm/s. It has been observed that the depth of penetration increases with increasing prosthesis insertion velocity. On the other hand, the maximum pressure in bone cement decreases with increasing prosthesis insertion velocity. It has been observed that there is more penetration through cancellous bone for pseudoplastic behaviour than rheopectic behaviour of bone cement.
New Approach to Ammonia Synthesis by Catalysis in Magnetic Field
Authors: Yahya Noorhana , Puspitasari Poppy , Koziol Krzysztof , Pavia Giuseppe
Published: February 2012

Ammonia production is a capital-intensive industry as it requires high temperature (400-500oC) and also high pressure (150-300 bar) for its daily operations. An earnest effort was made to synthese ammonia gas using an in-house designed microreactor. The production of ammonia was carried out in a magnetic field reaction zone, with the reaction temperature of 30°C - 280°C and ambient operation pressure. Mn0.8Zn0.2Fe2O4 nanoparticles, synthesized using the sol gel method, were used as the catalyst for the ammonia synthesis. XRD confirmed the single phase ferrites and FESEM images revealed nanofibre-like morphology when sintered at 700oC in argon gas. Electron diffraction was performed using HRTEM and obtained diffraction patterns confirmed the crystal structure of the catalyst. By using the Kjeldahl method it was found that the reaction carried out in 1 Tesla magnetic field gave approximately 46% ammonia yield. The proposed new method could be appealing for ammonia manufacturers due to highly economical implication which may offer urea producers a potential contender in the competitive market place.
Chitosan Capped Colloidal Gold Nanoparticles for Sensing Zinc Ions in Water
Authors: Promnimit Sujira , Bera T. , Baruah S. , Dutta Joydeep
Published: February 2012

In this work, we report sensing of Zn2+ ions using chitosan capped colloidal gold nanoparticles in aqueous media. The chitosan capping not just acted as an electro-static stabilizer to the colloidal gold nanoparticles, but also could bind to Zn2+ ions if present in the solution. However, the Zn2+ ions chelation to the chitosan capping decreased the stability of the colloidal gold hence shifted the surface plasmon peak to higher wavelengths. The extent of this red shift was found to be dependent on the concentration of the Zn2+ ions and therefore the presence of Zn2+ ions could be determined both qualitatively and quantitatively by analyzing the optical spectra of the chitosan capped gold nanoparticles. The sensing capability was also affected by the size of the nanoparticles, which could be tuned by adjusting the molar ratio of the reducing agent and the gold salt to the desired levels. Optical characteristics showed satisfactory results in estimating the amount of Zn2+ ions in water. This is thus a promising method for on the spot assessment of heavy metal ion concentrations in water.
Adsorption of Lead Ions in Aqueous Solution Using Yttrium Oxide Nanoparticles
Authors: Sadjadi Sodeh , Ahmadi Seyed Javad , Hosseinpour Morteza
Published: February 2012

By a single-step supercritical hydrothermal synthesis method, yttrium oxide nanoparticles were successfully prepared without additional treatment. Yttrium oxide nanoparticles were employed as an adsorbent to study the adsorption of some heavy metal ions. This study revealed that nano structure yttrium oxide was an effective adsorbent for removal of lead ions from aqueous solutions.
Friction Stir Processing of Commercial Grade Marine Alloys to Enable Superplastic Forming
Authors: Smith Christopher B. , Mohan Arun , Mishra Rajiv S. , Mahoney Murray , Miles Mike , Gillis Scott M. , Cerveny Lee M. , Opichka Gerald
Published: February 2012

The use of friction stir processing (FSP) on marine grade aluminum sheet has been investigated with the objective of locally enhancing the material properties. This can potentially allow low cost commercial grade aluminum to be used in superplastic forming applications or further enhance the formability to allow more complex geometries to be formed. FSP has been demonstrated to enable superplasticity (uniform elongations >250%) in 5083-H116 over a range of friction stir processing conditions.
Constitutive Modeling of Low-Temperature Superplastic Flow of Ultrafine Ti-6Al-4V Sheet Material
Authors: Semiatin S. Lee , Sargent Gordon A.
Published: February 2012

The low-temperature superplastic flow behavior of two lots of Ti-6Al-4V sheet with an ultrafine microstructure was modeled. One lot (Sheet A) had an equiaxed-alpha starting microstructure; the flow stress/flow hardening exhibited by this material was explained on the basis of the Bird-Mukherjee-Dorn constitutive equation. The other material (Sheet B), having a mixed equiaxed- and remnant-lamellar alpha microstructure, underwent flow softening, flow hardening, or steady-state flow depending on test temperature and strain rate. These behaviors were interpreted in the context of a dynamic spheroidization model. The apparent flow softening at the end of all of the flow curves was explained using a simple flow-localization model.
Energy Absorption Capability of Zn-22Al Superplastic Alloy Foam Manufactured through Melt Foaming Process
Authors: Sekido Kenji , Seo Teppei , Kitazono Koichi
Published: February 2012

Superplastic Zn-22Al alloy foams were manufactured through the melt foaming process using titanium hydride powder as a foaming agent. The compressive properties of the Zn-22Al foams were investigated under quasi-static and dynamic loading conditions. Experimental results show that the flow stress and the energy absorption of the Zn-22Al foam significantly increased with increasing the strain rate. At high strain rate region, the energy absorption of the Zn-22Al foams is also larger than that of conventional aluminum foams. These behaviors are due to superplastic deformation of cell walls.
High-Strain-Rate Superplastic Flow Mechanism in ZrO2-30vol% Spinel Two-Phase Composite
Authors: Morita Koji , Hiraga Keijiro , Kim Byung Nam , Yoshida Hidehiro
Published: February 2012

High-strain-rate superplasticity (HSRS) can be attained in tetragonal ZrO2-30vol% MgAl2O4 spinel composite. In order to examine the flow behavior of the two-phase composite, the standard rule of the mixture model was employed. The strain rate of the composite can be explained by the isostrain model that is predicted from the data set of Al2O3 doped ZrO2 and spinel polycrystals. For the isostrain model, since the strain and strain rate are the same for ZrO2 and spinel phases, the harder ZrO2 phase carries more of the stress in the composite. In order to preserve homogeneous deformation and material continuity, a concomitant accommodation process within the harder ZrO2 grains is also necessary. For HSRS in the ZrO2-spinel composite, therefore, the rate of deformation may be controlled by the slower dislocation recovery process limited by the lattice diffusion within harder ZrO2 grains rather than within spinel grains.
Heat Resistant Ni-Cr-Fe Steels for Superplastic Forming Dies: From Material Microstructure to Die Design
Authors: Bernhart Gérard , Velay Vincent , Lours Philippe
Published: February 2012

During superplastic forming, dies are subjected to high temperatures and severe environmental conditions. Optimum material grade choice and die design have to take into account all these combined parameters. Microstructure evolution and high temperature mechanical properties are investigated and reported for various Heat Resistant Cast Steels. New die concepts are suggested for energy and cost savings.
On the Development of Viable Cruciform-Shaped Specimens: Towards Accurate Elevated Temperature Biaxial Testing of Lightweight Materials
Authors: Abu-Farha Fadi K. , Hector Louis G. , Nazzal Mohammed A.
Published: February 2012

This paper is focused on the development of viable cruciform-shaped specimen geometries where large biaxial plastic deformation can be achieved within their gauge areas. A custom-built balanced biaxial testing fixture is used to plastically deform a variety of carefully-designed AZ31B-H24 magnesium specimens until failure. Images recorded from a digital camera positioned to monitor deformation in the gauge area of each specimen are used to compute the strain fields with a digital image correlation (DIC) algorithm. The viability of each design is validated based on the extent of biaxiality of measured strains and its ability to promote plastic deformation within its gauge area up until failure. The study provides key insights into the influences of certain geometrical parameters on deformation-biaxiality in cruciform specimens.
Quantitative Study of Soil Erosion in Henan Province Based on GIS
Authors: Li Jun Ling , Zou Chun Hui , Zhang Gang , Liu Zhong Yang
Published: February 2012

Based on a large number of researches, in according with the actual situation in geography and geology environment in Henan Province, this paper summed up the evaluation methods of soil erosion for Henan. Based on RUSLE mode, first of all, soil erosion model needed to get rainfall erosivity factor, soil erodibility factor, terrain factor, vegetation cover and soil and water conservation measures factor. Henan soil erosion intensity distribution was obtained according to soil erosion prediction formula In the Raster Calculator module of ARCGIS. Then to be Henan soil erosion strength grade distribution according to sl190-96 classification standard. Results show that low-level is the main soil erosion level. High-level, ultra-high-level and acute also happen, but their percentages are relative low. The high-level, ultra-high-level and acute soil erosion distribute mainly in southland region. The soil erosion situation would become clear, and provide a scientific reference for the government decision-making and provides a theoretical basis for future research.
Estimation of Cyanobacteria Blooms Monitoring Ability of HJ-1 CCD Data
Authors: Zhou Zheng , Zhao Yuan Ling , Fan Deng Ke , Wang Zhi Fang
Published: February 2012

HJ-1 satellite system consists of two optical CCD sensors, which can support real-time data for environment monitoring because of its high temporal and spatial resolution, so that there is great potential in water quality monitoring for inland lake. In this article, we analyze the ability of cyanobacteria blooms monitoring using the HJ-1 CCD data. First, the HJ-1 satellite is introduced and the potential ability in cyanobacteria blooms monitoring is discussed. Second, the HJ-1 CCD data and MODIS data are preprocessed and analyzed. Finally, the relative accuracy between the results of HJ-1 CCD and MODIS data are analyzed. The results indicate that the HJ-1 CCD data improve the cyanobacteria blooms monitoring ability in same spatial and temporal resolution.
Polarized Bidirectional Reflectance Spectra of Polished Granite
Authors: Yan Lei , Xiang Yun , Chen Wei , Zhao Yun Sheng
Published: February 2012

The granite is widely used for city architectural decoration, outdoor sculpture. Study on granite reflection is important for artificial building recognition and rock or mineral exploration. The Bidirectional Reflectance Distribution Function (BRDF) is used in conventional remote sensing to characterize the geometrical scatter of materials. Polarization occurs with multi-angle scatter. 90°and 0°polarized bidirectional reflection along the waveband of 300~2500nm for various view azimuth and zenith angles on polished granite are acquired. DOP then is calculated.
The Optical and Thermal Properties of Asian Dust over Ocean
Authors: Hao Zeng Zhou , Gong Fang , Ren Lin , Pan De Lu
Published: February 2012

Asian dust storms, which can long range transport and pass through the China Sea, often occur on spring. During this process, dust storm makes some impact on marine ecology and region climate, and the present of Asian dust aerosols over ocean takes some difficult for cloud detection, atmosphere correction of ocean color and sea surface temperature retrieval. Study on Asian dust aerosol properties over ocean is the basis of satellite remote sensing, which is a powerful tool to study dust over ocean. In this paper, the optical and thermal properties of Asian dust aerosol are presented by combining the Moderate Resolution Imaging Spectroradiometer (MODIS) observations and Streamer model simulations. By compare, the reflectance of dust aerosol over ocean at the visible band2, band3 and the near-infrared band6 of MODIS have some significant features, which are different from others, it satisfies Rb3<Rb6<Rb2 for strong dust aerosol over ocean, the weak dust aerosol meets Rb6<Rb2<Rb3, and the dust reflectance is from 0.1 to 0.3. At the thermal atmospheric windows bands which include band29, 31 and 32, for cloud and clear water region, the brightness temperature at band32 is highest and the temperature at band31 is close to band32. However, for dust aerosols, the brightness temperature at band32 is much greater than those at band29, band31, and the brightness temperature difference between band29 and band31 is small and the lower is the difference, the stronger is the dust aerosol. Those Asian dust aerosol characteristics are nice and useful for dust detection, dust retrieval over ocean, and deep study for marine environment and ecology.
Band Gap and Conductivity Measurement of TiO2 Thin Films Deposited by Sol-Gel Spin Coating Method
Authors: Rathee Davinder , Kumar Mukesh , Arya Sandeep K. , Sharma Mukesh
Published: February 2012

Thin films of TiO2have been deposited on to cleaned glass substrate by sol gel spin coating method. The XRD analyses confirm different crystalline phases of TiO2thin films. The grain size calculated by the help of Scherer’s formula and found to be 23nm, 37nm and 54 nm respectively for TiO2(004), TiO2(200) and TiO2(211) orientations. The band gap was calculated 3.6 eV by UV-spectrophotometer. The refractive index of the TiO2film was measured by Ellipsometry and found to be 2.33. Conductivity was measured using Current voltage (I-V) characteristics. To determine composition and thermal stability, thermo gravimetric Analyzer (TGA) and Differential Scanning Calorimeter (DSC) analysis was made on samples.
Study on the Measuring Space of Flexible Arm Coordinate Measuring Machines
Authors: Gao Guan Bin , Wang Wen
Published: February 2012

The measuring space is the set of positions a flexible arm coordinate measuring machine (FACMM) can reach, and it is an important measure for the evaluation of a FACMM. To study the measuring space of FACMMs the kinematic model was established. Furthermore, a new method based on Monte Carlo method to calculate the measuring space of FACMMs was proposed. The method generates the data of joint angles with Monte Carlo method, which is used to calculate the coordinates of the FACMM’s probe through the kinematic model. These coordinates make up the measuring space. The results of the analysis on the measuring space show that the measuring space of FACMMs is not a sphere usually considered as but an ellipsoid, and there is lack of flexibility near the border of the measuring space.
The Effect of Atmosphere Disturbances on Laser Beam Propagation
Authors: Hashemipour Seyed Hamid , Ogli A. Salman , Mohammadian Nasim
Published: February 2012

In this article, we probe the atmosphere disturbance such as Attenuation, Scattering, turbulence and thermal blooming on the laser beam propagated it. For investigating, we designed software which gives the vertically propagation characteristics of a general-type beam in atmosphere, based on the Huygens–Fresnel principle. When the required source and medium parameters are entered, the simulator yields the average intensity profile along the propagation axis in a video format. The results show that the peak value of the average intensity can be astonishingly affected by atmospheric turbulence, thermal blooming effect (for typical high power lasers) and the laser beam diameter.
Infrared and Visible Image Registration Base on SIFT Features
Authors: Yang Kai Wei , Chen Tian Hua , Xing Su Xia , Li Jing Xian
Published: February 2012

In the System of Target Tracking Recognition, infrared sensors and visible light sensors are two kinds of the most commonly used sensors; fusion effectively for these two images can greatly enhance the accuracy and reliability of identification. Improving the accuracy of registration in infrared light and visible light images by modifying the SIFT algorithm, allowing infrared images and visible images more quickly and accurately register. The method can produce good results for registration by infrared image histogram equa-lization, reasonable to reduce the level of Gaussian blur in the pyramid establishment process of sift algorithm, appropriate adjustments to thresholds and limits the scope of direction of sub-gradient descriptor. The features are invariant to rotation, image scale and change in illumination.
A New Data Transformation Method for Cbers-02b Multi-Spectral Images
Authors: Zhang Cheng Wen , Tang Jia Kui , Mi Su Juan , Zhao Li Jun , Li Yong Zhi , Yu Xin Ju
Published: February 2012

According to the detailed studies on the data of China-Brazil earth resources satellite-02B (CBERS-02B) and the LBV data transform method proposed by the previous researcher, a new LBV data transformation equations for CBERS-02B data was specially proposed. A transformation experiment on CBERS-02B data showed that the LBV transformed result images were more vivid, and the features of result images were more easily to be classified than the fault color composite images of original bands. In order to evaluate the performance of this proposed method, the maximum likelihood supervised classification method was used. The final classification results showed that the accuracy of the LBV transformed image is obviously better than that of the fault color composite images of original bands, which demonstrated that the proposed LBV transformation method for CBERS-02B has good potential for CBERS-02B data in the future applications.