bluuebunny/crossref_metadata_2025 huggingface dataset:
Ion Beam Irradiation of Lanthanum Compounds in the Series La2O3-TiO2
Authors: Whittle Karl , Blackford Mark , Aughterson Robert , Smith Katherine L , Lumpkin Gregory R , Zaluzec Nestor J
Published: August 2010

Thin crystals of La2O3, La2/3TiO3, La2TiO5, and La2Ti2O7 have been irradiated in situ using 1 MeV Kr2+ ions in the Intermediate Voltage Electron Microscope-Tandem User Facility (IVEM-Tandem), at the Argonne National Laboratory (ANL). We observed that La2O3 remained crystalline to a fluence greater than 3.1 × 1016 ions cm-2 at a temperature of 50 K. The four binary oxide compounds in the two systems were observed through the crystalline-amorphous transition as a function of ion fluence and temperature. Results from the ion irradiations give critical temperatures for amorphisation (Tc) of 840 K for La2Ti2O7, 865 K for La2/3TiO3, and 1027 K for La2TiO5. The Tc values observed in this study, together with previous data for TiO2, are discussed with reference to the phase diagrams for La2O3-TiO2 systems and the different local environments within the crystal structures. Results suggest an observable inverse correlation between Tc and melting temperature (Tm) in the two systems.
Nanostructured Silicon-based Composites for High Temperature Thermoelectric Applications
Authors: Bux Sabah , Kaner Richard B , Fleurial Jean-Pierre
Published: August 2010

Recently nanostructured bulk silicon and silicon-germanium have achieved large increases in the thermoelectric figure of merit (ZT). The ZT enhancement is attributed to a significant reduction in the lattice thermal conductivity while maintaining relatively high carrier mobility. Silicon-based thermoelectric devices are attractive due to their low-toxicity, thermal stability, low density, relative abundance and low cost of production. Although significant enhancements in ZT have been achieved using the nanostructuring route, additional decoupling of the thermal and electric transport terms is still necessary in order for silicon-based materials to be viable for thermoelectric applications such as waste heat recovery or radioisotope thermoelectric generators. It is theorized that additional increases in ZT could be achieved by forming composites with nanostructured inert inclusions to further scatter the heat-carrying phonons. Here we present the impact of insulating and conductive nanoparticle composites on ZT. The nanostructured composites are formed via ball milling and high pressure sintering of the nanoparticles. The thermoelectric properties and microstructure of the silicon-based composites are discussed.
Hybrid Thermal Behavior from Thermoelectrics to Heat Sinking of a Thin Si Membrane with Stretched Ge Quantum Dots
Authors: Gillet Jean-Numa
Published: August 2010

A membranous nanomaterial showing, for the first time, a hybrid thermal behavior between insulating and dissipative regimes is proposed with applications in both thermoelectrics (low thermal conductivity) and passive heat sinking (high thermal conductivity). While other compounds could be chosen, the nanomaterial is made up of a thin Si membrane covered by Ge quantum dots (QDs) with epitaxial facets. The QDs are voluntarily stretched in the direction [010] or y parallel to the membrane to form elongated islands. The broken symmetry induces an exalted phonon wave-guiding in y. Therefore, when hot and cold junctions are connected to the membrane following the stretching direction [010], the anisotropic thermal conductivity shows a significant exaltation with respect to the in-plane orthogonal direction [100] or x, where the Ge islands have the smallest average size. An example nanomaterial is obtained by repetition of molecular supercell slabs containing 4348 atoms each. The thermal conductivity shows a marked exaltation higher than 22 folds, from 1.5 to 33.5 W/m/K when the connection direction between the hot and cold junctions is rotated by 90° from x to y. Therefore, the nanomaterial presents a changing thermal behavior from insulation to passive dissipation when the heat propagation direction is modified from x to y. As a result, it could be used for the design of passive heat sinkers (from the phonons) when the two junctions are connected following [010]. In contrast, a thermal insulating behavior appears when the junctions are linked following [100]. This direction can be as well used for cooling applications. However, in this case, cooling is differently generated using the Peltier effect (from the electrons). Seebeck generation can be also envisioned in the direction [100].
Effect of partial filling of the structural vacant sites on the thermoelectric properties of Zr0.25Hf0.75NiSn half-Heusler alloy
Authors: Makongo Mangan Julien Pierre Amelie , Misra Dinesh , Takas Nathan J. , Stokes Kevin L. , Gabrisch Heike , Poudeu Pierre F. P.
Published: August 2010

Composites containing mainly-half-Heusler MNiSn (HH) and full-Heusler MNi2Sn (FH) were prepared by solid state reaction of a mixture of polycrystalline bulk HH alloy with various concentrations of Ni up to 10 wt.%. Electrical conductivities, thermal conductivities and thermopowers of spark plasma sintered specimens of the as synthesized composite materials were measured in the temperature range from 300 K to 750 K. The conduction type of the composite changes from semiconductor to semimetal for Ni concentrations up to 2 wt.% and from semimetal to metal for higher Ni concentrations above 5 wt.%. A strong reduction in lattice thermal conductivity was observed for the composite containing 10 wt. % Ni inclusions.
MeV Si Ions Bombardment Effects on the Thermoelectric Properties of Si/Si+Ge Multi-Layer Superlttice Nanolayered Films
Authors: Pugh Marcus , Budak S. , Smith Cydale , Chacha John , Ogbara Kudus , Heidary Kaveh , Johnson R. B. , Muntele Clauidu , ILA D.
Published: August 2010

Effective thermoelectric materials have a low thermal conductivity and a high electrical conductivity. The performance of the thermoelectric materials and devices is shown by a dimensionless figure of merit, ZT = S2σT/K, where S is the Seebeck coefficient, σ is the electrical conductivity, T is the absolute temperature and K is the thermal conductivity. ZT can be increased by increasing S, increasing σ or decreasing K. MeV ion bombardment caused defects and disorder in the film and the grain boundaries of these nano-scale clusters increase phonon scattering and increase the chance of an inelastic interaction and phonon annihilation. We have prepared 100 alternating layers of Si/Si+Ge nanolayered superlattice films using the ion beam assisted deposition (IBAD). The 5 MeV Si ions bombardments have been performed using the AAMU Pelletron ion beam accelerator to make quantum clusters in the nanolayered superlattice films to decrease the cross plane thermal conductivity, increase the cross plane Seebeck coefficient and cross plane electrical conductivity. We have characterized the thermoelectric thin films before and after Si ion bombardments as we measured the cross-plane Seebeck coefficient, the cross-plane electrical conductivity, and the cross-plane thermal conductivity for different fluences
Synthesis and Thermoelectric Properties of Y-doped Ca3Co4O9Ceramics
Authors: Rodriguez Julio E. , Moreno Luis Carlos
Published: August 2010

Polycrystalline ceramics with nominal composition of Ca3-xYxCo4O9+δ(0≤x≤0.10) were grown using the citrate-complex method. Thermoelectric properties were studied using Seebeck coefficient S(T) and electrical resistivity ρ(T) measurements. These transport properties were studied in the temperature range between 100 and 290K. For low doping levels in Y substituted samples (x≤0.06) the magnitude of S(T) and ρ(T) decreases with yttrium content. The temperature behavior of S(T) and ρ(T) was interpreted in terms of the small-polaron hopping mechanism. From S(T) and ρ(T) data it was possible to calculate the thermoelectric power factor PF, which reaches maximum values close to 23 μW/K2-cm. These values become these compounds promissory thermoelectric compounds for use in low temperature thermoelectric applications.
Defects in Irradiated ZnO Thin Films Studied by Photoluminescence and Photoconductivity
Authors: Schwarz Reinhard , Ayouchi Rachid , Brandão Marta , Marques Carlos , Alves Eduardo , Pinnisch Melanie , Hofmann Detlev , Meyer Bruno
Published: August 2010

Pulsed-laser-deposited ZnO thin films were exposed to a 1.5 MeV helium ion beam to study the changes in radiative and non-radiative recombination. We first measured photoluminescence (PL) spectra at 4.2 K excited with the 325 nm line of a HeCd laser. The as-deposited films showed a donor-bound exciton peak at 3.3567 eV attributed to Zn interstitials. After irradiation the donor-bound-exciton dominated PL spectra shifted to acceptor-bound behaviour with a signal at 3.3519 eV, tentatively attributed to Li or Na acceptors. In contrast to the approximately 30 % decrease of the PL signal near the band edge, we observed a strong concomitant enhancement of the green/orange PL band, located between 2.1 eV and 2.8 eV, by a factor of over 4. Candidates for those transitions are Li impurities and/or O vacancies. For comparison, the steady-state photocurrent decreased strongly in the irradiated region, which can also be attributed to increased non-radiative recombination through oxygen-related defects.
Impact of a-Si:H structural properties on the annealing behavior of a-Si:H/c-Si heterostructures used as precursors for high-efficiency solar cells
Authors: Schulze Tim Ferdinand , Beushausen Hannes Ner , Leendertz Caspar , Dobrich Anja , Hannappel Thomas , Korte Lars , Rech Bernd
Published: August 2010

We analyze the dependence of the interface defect density Dit in amorphous/crystalline (a-Si:H/c-Si) heterostructures on the microscopic properties of the ultrathin (10nm) undoped a-Si:H films. It is shown that the hydrogen bonding configuration, probed by infrared spectroscopy, determines the a-Si:H network disorder, which in turn governs the annealing behavior of these structures upon a short thermal treatment at moderate temperatures (T ≤ 200°C). While the as-deposited Dit seems to be determined by the local structure at the interface, the final state of the annealed samples is determined by the bulk a-Si:H network strain as reflected in the valence band tail slope. Thus it appears valid to treat the equilibrated a-Si:H/c-Si interface as a 2D-layer that has the projected defect properties of the 3D a-Si:H bulk.
Reactions of H with C in Multicrystalline Si Solar-cell Materials
Authors: Peng Chao , Stravola Michael , Zhang Haoxiang , Yelundur Vijay , Rohatgi Ajeet , Carnel Lode , Seacrist Mike , Kalejs Juris
Published: August 2010

Hydrogen is commonly introduced into silicon solar cells to reduce the deleterious effects of defects and to increase cell efficiency. When hydrogen is introduced into multicrystalline Si that is often used for the fabrication of solar cells, the H atoms become trapped by carbon impurities to produce defect structures known at H2*(C). These defects act as both a source and a sink for hydrogen in H-related defect reactions. IR spectroscopy has been used to determine what H- and C-related defects are formed in multicrystalline Si when the carbon concentration is varied. A process that is used by industry to introduce hydrogen into Si solar cells is the post-deposition annealing of a hydrogen-rich SiNx layer. The H2*(C) defects provide a strategy for estimating the concentration and penetration depth of the hydrogen that is introduced by this method.
Trap State Photoluminescence of Nanocrystalline and Bulk TiO2,: Implications for Carrier Transport
Authors: McHale Jeanne Louise , Rich Christopher C. , Knorr Fritz J.
Published: August 2010

The visible photoluminescence of nanocrystalline TiO2 is examined in the presence of surface binding agents and as a function of vacuum annealing in order to probe the molecular nature of surface defects. The photoluminesence (PL) of bulk crystals of anatase TiO2 from (101) and (001) planes is also reported in order to test the hypothesis that electron and hole traps are spatially isolated on different crystal planes. We find that a number of hole scavengers are capable of quenching the PL associated with trapped electrons, while the ability of oxygen to quench PL through electron scavenging varies with the nature of the sample. We conclude that hole scavengers exert their influence on the PL through reaction with valence band holes rather than with spatially isolated trapped holes. Scavenging of electrons by O2, on the other hand, depends on adsorption at oxygen vacancies and varies with TiO2 sample.
Preparation of Amazingly Hard polyHIPE material from a Direct Emulsion
Authors: Youssef Carlos , Backov Rénal , Treguer Mona , Birot Marc , Deleuze Hervé
Published: August 2010

Interconnected microcellular polymeric monoliths having unexpected high mechanical strength have been prepared using the High Internal Phase Emulsion methodology. Direct concentrated emulsions of aqueous 5-amino-1-vinyl-[1,2,3,4]tetrazole mixed with low molar (5 %) fractions of N,N'-methylenebisacrylamide (MBA) as cross-linking agent were prepared using dodecane as dispersed phase and a mixture of hydrophilic surfactants. “Reverse” polyHIPE materials were obtained after radical copolymerization, solvent extraction and drying. Their morphology, chemical composition and physico-chemical behaviour are discussed.
Enzyme Triggered Gelation of Arginine Containing Ionic-Peptides
Authors: Guilbaud Jean-Baptiste A M , Miller Aline , Saiani Alberto
Published: August 2010

We have investigated the possibility of using the protease enzyme thermolysin to catalyse the synthesis and gelation of ionic-complementary peptides from non-gelling peptide precursors. In the described system, thermolysin was added at a fixed concentration (0.3 mg mL−1) to solutions (25 - 100 mg mL−1) of a short tetra-peptide FEFR. Initially, the protease partially hydrolysed the tetrapeptide into di-peptides in all samples. Subsequently, longer peptide sequences were found to form through reverse-hydrolysis and their stability was found to be dependent on their self-assembling properties. The sequences that self-assembled into anti-parallel β-sheet rich fibres became the stable products for the reverse hydrolysis reaction, while the others formed were unstable and disappeared with increasing incubation time. Ultimately, the main product of the system was octa-peptide, which suggests that it represents the thermodynamically favoured product of this dynamic library.
A moth-eye bio-inspired approach to planar isotropic diffraction
Authors: Stavroulakis Petros Ioannis , Boden Stuart , Bagnall Darren
Published: August 2010

A regular hexagonally packed biomimetic moth-eye antireflective surface acts as a diffraction grating at short wavelengths of the visible spectrum and shallow angles of incidence. These gratings display strong backscattered iridescence with 6-fold optical symmetry. The optical symmetry of real moth eyes is effectively infinite as nature utilizes large number of uniquely orientated domains. In this work we report on a biomimetic moth-eye surface created via nanosphere lithography with a very large distribution of close-packed tessellated domains and the resulting optical symmetry is compared to that of another widely known highly isotropic diffraction grating, also inspired by nature, the sunflower pattern. A white-light laser reflectometry system is used to measure and compare the diffraction pattern isotropy from both structures. The tessellated close-packed structure diffraction pattern approaches that of infinite optical symmetry even though the underlying pattern only possesses a six-fold symmetry. Hence, the angular isotropy observed for the sunflower pattern is replicated to a large extent via a self-assembly procedure, whilst circumventing the complicated design and manufacturing requirements of the sunflower pattern.
Effect of environment on mechanical properties of micron sized beams of bone fabricated using FIB
Authors: Barber Asa H , Jimenez-Palomar Ines
Published: August 2010

Bone is a complex material with structural features varying over many different length scales. Lamellae in bone are discrete units of collagen fibril arrays that are the dominant structural feature at length scales of a few microns. The mechanical properties of bone are importantly dependent on the synergy between the lamellae and structural features at other length scales. However, the mechanical properties at this micron level will be indicative of the bone material itself and ignores the structural and geometric organizations prevalent at larger length scales. The isolation of volumes of bone at the lamellar level requires precision cutting methodology and this paper exploits Focused Ion Beam (FIB) methods to mill small cantilever beams from bulk bone material. Importantly, FIB milling can only be performed in a relatively high vacuum environment. Atomic Force Microscopy (AFM) mechanical tests are therefore performed in two environments, high vacuum and air in order to assess the effects of vacuum on bone beam mechanical behaviour. Our results indicate that little difference in the bone beam elastic modulus is found from bending experiments at deflections up to 100nm in different environments.
Simulation of a temperature rise in concrete incorporating silica fume
Authors: Wang X. , Lee H. , Shin S.-W. , Golden J.S.
Published: August 2010

Silica fume is a by-product of induction arc furnaces and has long been used as a mineral admixture to produce high-strength, high-performance concrete. Owing to the pozzolanic reaction between calcium hydroxide and silica fume, compared with Portland cement, the hydration of concrete containing silica fume is much more complex. In this paper, by considering the production of calcium hydroxide in cement hydration and its consumption in the pozzolanic reaction, a numerical model is proposed to simulate the hydration of concrete containing silica fume. The heat evolution rate of silica fume concrete is determined from the contribution of the cement hydration and the pozzolanic reaction. Furthermore, the temperature rise in silica fume concrete is evaluated based on the degree of hydration of cement and silica fume. The proposed model is verified using experimental data on concrete with different water-to-cement ratios and silica fume substitution ratios.
River modelling and flood mitigation in a Belgian catchment
Authors: Duy B. Khuat , Archambeau P. , Dewals B. J. , Erpicum S. , Pirotton M.
Published: August 2010

This paper describes the steps followed to propose solutions to recurring flooding problems in a Belgian catchment. First, the hydraulic capacity (maximum discharge before bank overflow) of the cross-sections was computed along the entire river by an iterative one-dimensional steady-state approach. In order to carry out these simulations, cross-sections from site surveys of the river were integrated into the model, as well as hydraulic structures such as culverts, footbridges and pipes. Second, the flooding problem was analysed with a time-dependent approach consisting of simulating floods following extreme rainfall events. The hydrological aspect was studied in a spatially distributed way using a multi-layer hydrological model. The available data on the basin such as the digital elevation model, the land-use and the pedology were exploited to identify the basic modelling parameters. The hydrological contribution was routed by a one-dimensional network resulting from the merging of the digital elevation model-based and the cross-section-based river networks. According to the results of the aforementioned steps, various local and catchment-wide solutions against flooding were proposed and analysed. The comparison of simulated situations before and after these improvements allowed the effectiveness of the proposed solutions to be checked.
Coagulation and disinfection in water treatment using Moringa
Authors: Ahmed T. , Kanwal R. , Hassan M. , Ayub N. , Scholz M. , McMinn W.
Published: August 2010

A low-cost technology for drinking water purification involving plant extracts that are harmful to potentially pathogenic bacteria was developed. The methanolic and aqueous extracts of different parts of the Moringa oleifera vegetable tree were examined for their antibacterial and coagulation properties. The extracts from buds and shoots showed more antibacterial activities against Staphylococcus aureus, Bacillus cereus var. mycoides, Pseudomonas aeruginosa, Klebsiella pneumonia and Shigella flexneri at 37°C than those obtained from leaves and seeds. The lowest minimum inhibitory concentrations and minimum bactericidal concentrations were observed for buds and shoots, and not for seeds and leaves. The seeds were associated with higher coagulation activity in comparison with other parts of the plant and alum. These results suggest that bud and seed extracts can be used for water treatment, avoiding the risk of contamination by water-borne pathogens and promoting an indigenous solution to disease control and environmental management.
68.4: Optical Properties of Visible‐Light Excited Phosphor Sheet (VEPS) System
Authors: Xiao Bo‐Wen , Hung Chien‐Hsiang , Huang Hsin‐Tao , Huang Yi‐Pai , Tien Chung‐Hao , Tsai Chuang‐Chuang , Shieh Han‐Ping D. , Chen Jerry , Lin Jeremy , Chang Win‐Chi
Published: August 2010

The optical properties in Visible‐light Excited Phosphor Sheet (VEPS) system were discussed and calculated. Different to the conventional LED backlight with white LEDs, VEPS system applies blue LED chips to excite the extrinsic flat YAG‐phosphor layer to perform uniform and flat lighting, that can further reduce the backlight thickness. A theoretical model was developed to optimize the structure of VEPS system. Consequently, the optimized result was demonstrated on the small‐Sized VEPS module.
69.1: Invited Paper: Materials and Component Solutions for Evolving Display Form Factors and Functionality
Authors: Bocko Peter L. , Clappin James C.
Published: August 2010

Several concurrent trends (large TV, small‐format viewing and novel functionality) are creating challenges for display components. In this paper, we review how component developments are progressing relative to these trends, including large substrates (Gen 10 and beyond), substrates with high thermal capability, and high‐strength cover glass.
P‐12: Stability of Nano‐Crystalline ZnO and Amorphous IGZO TFTs under Bias Stress
Authors: Yang ShinHyuk , Shin Jae‐heon , Park Sang‐Hee Ko , Cheong Woo‐Seok , Hwang Chi‐Sun , Yoon Sung‐Min , Cho Doo‐Hee , Ryu Min‐Ki , Chu Hye Yong , Cho Kyoung Ik , Jang Jin
Published: August 2010

We have studied the stabilities of PEALD grown ZnO and sputtered IGZO TFTs under various gate biases and room‐temperature recovery properties. The threshold voltage shift highly depends on the applied gate bias stress mainly due to charge trapping. Drain bias effect in oxide TFTs showed different behavior which is related to the crystalline phase.
P‐24: Projection System and LED Source for Cell‐Illuminating Experiment
Authors: Ou Chung‐Jen , Shen Ching‐I , Ou Chung‐Ming
Published: August 2010

Commercialized projection system and the LED without secondary optical lens are serving as the light source for cell illuminating experiments. Feasibilities and the application for these two approaches are discussed.
P‐27: Light Printer for Optical Rewritable Electronic Paper
Authors: Yu Qiang , Murauski Anatoli , Du Tao , Yao Lishuang , Chigrinov Vladimir , Kwok Hoi Sing
Published: August 2010

Composed of a transmissive super‐twisted‐nematic(STN) liquid crystal display (LCD) and an external driving circuit system, the light printer for optical rewritable (ORW) electronic paper (e‐paper) can easily hold or change the display image, which is used as the mask pattern of ORW electronic paper.
P‐38: 1Gbps/lane Low Overhead Clock‐Shared Differential Signaling (CSDS) — An Efficient Interface for Large‐Size TFT‐LCDs
Authors: Kim Nyuntae , Koo Kyoung‐Hoi , Kang Sung‐ho , Park Jaejin , Jung Jiwoon , Jung Won‐Gap , Park Donguk , Kim Jin‐Ho , Kim Taejin , Choi Youngmin , Lee Jae‐Youl , Choi Yoon‐kyung , Kim Jong‐seon , Park Byeong‐Ha , Lee Myunghee
Published: August 2010

A clock‐shared differential signaling (CSDS) scheme is newly proposed to support high resolution and large‐Size TFT‐LCDs with less than 3% overheads compared with transmitted data. CSDS adopts single‐level, multi‐dropped differential clocks which is shared among source driver ICs (CDs) and point‐to‐point connection for data lines. The protocol supporting CSDS makes the overhead of data transmission to be less than a few percent, which makes CSDS superior to other interfaces in terms of signal integrity, EMI, simple transmitter, and etc. It also supports flexible CD controls via just changing register values which are delivered by its protocol. And it is proved that CSDS supports 1.1Gbps per lane, which can cover next generation panels such as UD class.
P‐55: Colorimetric Image Splitting for High‐Dynamic‐Range Displays
Authors: Luka Stefan , Ferwerda James A.
Published: August 2010

In dual layer high dynamic range displays, images are formed through the optical modulation of a front panel image by a backlight image. We present a colorimetric method for calculating the backlight image that maximizes gamut utilization while minimizing quantization errors, producing displayed images with deeper, more saturated colors.
P‐160: Ultra Simple White Organic Light‐Emitting Diodes Using only Three Organic Materials
Authors: Seo Ji Hoon , Kim Jun Ho , Koo Ja Ryong , Seo Ji Hyun , Park Jung Sun , Kim Young Kwan , Hyung Gun Woo , Hwang Jang Hwan , Lee Kum Hee , Kim Jung Yeon , Yoon Seung Soo , Kim You Hyun , Kim Woo Young
Published: August 2010

The authors have demonstrated ultra simple white organic light‐emitting diodes using only three organic materials, 2‐methyl‐9,10‐ di(2‐naphthyl)anthracene (MADN), new blue fluorescent emitter (NBFE), and new red fluorescent emitter (NRFE). The fluorescent white organic light‐emitting diode fabricated in this study showed the high external quantum efficiency of 6.48%, the luminous efficiency of 13.10 cd/A, and CIEx,y coordinates of (0.33, 0.42) at 100 cd/m2, respectively.
P‐163: Achieving High Directionality and Extraction of Light Emission from Polymer Light Emitting Diodes Via ITO/Organic Photonic Crystals
Authors: Liao Lun‐De , Chao Paul C.‐P. , Chen In‐Chen , Meng Hsin‐Fei , Chai Che‐Hong , Lin Chin‐Teng , Huang Yuan‐Pin
Published: August 2010

The objective of this study is to achieve high directionality and extraction of light emission from polymer light‐emitting diodes via optimizing photonic crystals (PCs). Genetic Algorithm is employed to search the optimal PC period, depth and filling factor. The large‐area PCs are fabricated by Focus Ion Beams for PLED, which is commercially viable, even applicable to active matrix PLED displays.
14.4: Novel Human‐Machine Interface (HMI) Design Enabled by Holographic Laser Projection
Authors: Buckley Edward , Stindt Dominik , Isele Robert
Published: August 2010

Despite the current proliferation of in‐car flat panel displays, designers continue to investigate alternatives to flat and rectangular thin‐film transistor (TFT) panels — principally to obtain differentiation by freedom of design using, for example, free‐form shapes, round displays, flexible displays or mechanical 3D solutions. A perfect demonstration was provided at the 2008 Paris Motor Show by the BMW Mini Center Globe, a novel instrument cluster design which combines lighting, a circular flat panel and a holographic laser projector provided by Light Blue Optics (LBO) to redefine the state of the art in human‐machine interface (HMI). In this paper, the authors will show how the incorporation of LBO's holographic laser projection technology can allow the construction of a unique display technology like the Mini Center Globe, and how such a combination of technologies represents a significant advance in the current state of the art in automotive displays.
P‐170: Micro‐Mirror Array Fabricated by the CMOS Process for Applications of MEMS Display
Authors: Kao Pin‐Hsu , Dai Ching‐Liang , Hsu Cheng‐Chih , Mo Chi‐Neng , Lee Chien‐Pang , Huang Ming‐Wei
Published: August 2010

This article describes a micro‐mirror array fabricated using the commercial 0.35μm CMOS (complementary metal oxide semiconductor) process and a simple maskless post‐process. The material of the micro‐mirror is aluminum and the sacrificial layer is silicon dioxide. The fabrication of the micro‐mirror array is compatible with the CMOS process, so the mirror array has a potential to integrate with circuitry on a chip. The post‐process utilize the BOE (buffered oxide etching) to remove the sacrificial layer and to suspend the micro mirror. The micro‐mirror contains a circular membrane and has four fixed beam. There are four fan‐ shaped electrodes below the micro mirror which is utilized to drive the micro mirror tilted. Each micro mirror has four rotatable directions and each direction is independent. Experimental results show the mirror has a tilting angle of about 0.93 ° at a driving voltage of 30 V.
15.2: Development of Driver‐Integrated Panel Using Amorphous In‐Ga‐Zn‐Oxide TFT
Authors: Osada Takeshi , Akimoto Kengo , Sato Takehisa , Ikeda Masataka , Tsubuku Masashi , Sakata Junichiro , Koyama Jun , Serikawa Tadashi , Yamazaki Shunpei
Published: August 2010

We designed, prototyped, and evaluated LCD integrated with a gate driver and a source driver using amorphous In‐Ga‐Zn‐Oxide TFTs having bottom‐gate bottom‐contact structure, thereby obtaining TFTs with superior characteristics. Then, we prototyped the world's first 4‐inch QVGA LCD and integrated the gate driver and source driver on the display panel.
15.3: AMOLED Driven by Solution‐Processed Oxide Semiconductor TFT
Authors: Ryu Myung Kwan , Park KyungBae , Seon Jong‐Baek , Park JeongII , Kee InSeo , Lee YoungGu , Lee Sang Yoon
Published: August 2010

We report an AMOLED fabricated with a solution‐processed indium zinc oxide (IZO) thin‐film transistor (TFT) backplane. The TFT has a bottom gate structure with SiNx gate insulator, spin‐coated IZO active layer, Mo source/drain electrode, and SiO2 passivation layer. The TFT exhibited the field effect mobility of 0.9 cm2/Vs, threshold voltage of 13.6 V, and high on/off current ratio of 1.8e7.
25.4L: Late‐News Paper: A Novel Polarizer Glasses‐Type 3D Displays with an Active Retarder
Authors: Jung Sung‐Min , Park Ju‐Un , Lee Seung‐Chul , Kim Wook‐Sung , Yang Myoung‐Su , Kang In‐Byeong , Chung In‐Jae
Published: August 2010

In this paper, we suggested a novel method achieving high resolution and high brightness in the glasses‐type 3D displays and fabricated a prototype of 15″ size in diagonal, which is composed of an active retarder synchronized with an image panel. The active retarder is configured to a TN mode to have a function of polarization switching for the input polarization states. We expect that the AR3D technology can give high resolution and high brightness for the 3D users with a convenience of simple polarizer glasses and an inexpensive cost compared with the shutter glasses type 3D display, where not only the image panel and but also the glasses should have an LCD panel.
31.4: Direct View and Projection Switchable Mobile Display
Authors: Huang Hsin‐Hsuan , Chen Cheng‐Huan , Lai Yu‐Cheng , Chang Yu‐Cheng , Huang Yi‐Pai , Shieh Han‐Ping D. , Chen Chih‐Wen
Published: August 2010

The function of mobile phone becomes more versatile as a personal assistant. In order to make display device optimized for different function of the mobile phone, this paper proposes a display device which can be switched among 2D direct view, 3D direct view and projection modes while using single liquid crystal(LC) panel as image source. The device features a highly collimated backlight unit and polymer dispersed liquid crystal(PDLC) diffuser at the back of the LC panel, and a switchable lenticular array as well as a stretchable projection lens in front. The ray tracing simulation has shown well controlled light path of the backlight module and sufficient image quality of the projection lens while maintaining the compactness of the device for mobile application.
35.3: High‐Performance Tandem White OLEDs Using a Li‐Free “P‐N” Connector
Authors: Hatwar Tukaram K. , Spindler Jeffrey P. , Begley William J. , Giesen David J. , Kondakov Denis Y. , Van Slyke Steven , Murano Sven , Kucur Erol , He Gufeng , Blochwitz‐Nimoth Jan
Published: August 2010

A nonmetallic connector has been developed for high‐efficiency tandem white architecture. Forming the “N” type layer using NDN‐26 doped into NET‐18 and inserting an organometallic thin layer between the “N” and “P” layers results in a high‐performance connector. An efficiency of 33 cd/A has been achieved at 6.7 V, 1000 cd/m2 and 10000K color temperature in a fluorescent based tandem emitter. This >15% EQE device also demonstrates a half‐life of ∼80,000 h at 1000 cd/m2.
39.1: Invited Paper: Optically Isotropic Nano‐Structured Liquid Crystal Composites for Display Applications
Authors: Kikuchi Hirotsugu , Haseba Yasuhiro , Yamamoto Shin‐ichi , Iwata Takashi , Higuchi Hiroki
Published: August 2010

In this paper, we present the phase behavior and electro‐optical Kerr effect of the optically isotropic liquid crystal composites, which require no surface treatment for device fabrication. Anomalously large Kerr constant, more than 10−8 mV−2 and fast response, less than sub‐milli‐second were observed at a room temperature.
39.3: Sub‐Millisecond Liquid Crystal Mode Utilizing Electro‐Optic Kerr Effect Comprising Polymer‐Stabilized Isotropic Liquid Crystals
Authors: Yang Young‐Cheol , Bao Rui , Li Kexuan , Yang Deng‐Ke
Published: August 2010

We report a polymer‐stabilized isotropic liquid crystal mode comprising submicro‐structured nematic liquid crystal polymer composites as an ultrafast display mode with sub‐millisecond response time. Electro‐optic Kerr effect is observed at the temperature lower than nematic‐isotropic transition temperature of the liquid crystal; the liquid crystal polymer composite in the cell exhibits an optically isotropic state at field‐off state and optical birefringence at field‐on state. The optically isotropic state of the liquid crystal at room temperature is achieved by randomly oriented polymer network formed.in the isotropic phase at an elevated temperature. In‐plane switching mode is used to induce the birefringence along the direction parallel to substrates.
39.4L: Late‐News Paper: Negative A‐Plates Using Stretched Polystyrene
Authors: Jiao Meizi , Gauza Sebastian , Li Yan , Yan Jin , Wu Shin‐Tson , Chiba Tsuyoshi
Published: August 2010

Negative A‐plates fabricated by mechanically stretching polystyrene are studied and their physical properties evaluated. A molecular model is developed to explain the underlying physical mechanisms. Examples of wide‐view liquid crystal displays using negative A‐plates are illustrated.
40.4: Glass Substrates for OLED Lighting with High Out‐Coupling Efficiency
Authors: Nakamura Nobuhiro , Fukumoto Nao , Sinapi Fabrice , Wada Naoya , Aoki Yumiko , Maeda Kei
Published: August 2010

Glass substrates which realize high out‐coupling efficiency OLEDs were developed. A scattering layer whose matrix was made of high refractive index glass was formed on a glass substrate. The out‐coupling efficiency of an OLED using this substrate is 1.8 times higher compared with an OLED using an untreated glass substrate.
43.3: RGB LED Backlight of Color Sequential Display with Precise Current‐Balance Control Technique
Authors: Chiu Chia‐Lin , Lee Yu‐Huei , Hsieh Chun‐Yu , Ho Ming‐Tsung , Chen Ke‐Horng , Li Ling , Chen Chih‐Chung
Published: August 2010

This paper proposes a high efficiency and precise current balance circuit in parallel RGB Light Emitting Diodes (LED) channels for color filter‐less panel display. The new technique not only enhances the current matching in each channel but also reduces the requirement of device numbers and external resistors. The error percentage of all channel LED currents can kept within 0.1% when the channel voltage has a voltage variation (Δ VCH) around 1. 1V. Furthermore, the proposed load dependent minimum drain voltage can effectively reduce the voltage drop across the precise current balance circuit. As a result, the efficiency of the LED driver can be improved.
47.2: Visual Preference for ClearType Technology
Authors: Farrell Joyce , Xu Jiajing , Larson Kevin , Wandell Brian
Published: August 2010

ClearType filtering is a sub‐pixel rendering method that improves the perceived image quality of text. The method renders text at subpixel resolution and then applies a one‐dimensional filter to reduce color artifacts. We performed behavioral and computational experiments to analyze the effect of varying the linear filter parameters. Specifically, we systematically varied the values of a symmetric, mean‐preserving, five‐tap filter; such filters are described by a two‐dimensional parameterization. We generated ClearType versions of the same letter from a large set of these filters and asked subjects to select the version that they preferred. Subjects' preferred renderings from a compact region in the two‐dimensional parameter space. Computational analyses show that the preference data are predicted by the SCIELAB metric, a spatio‐chromatic metric of human visual sensitivity.
50.3: A Video‐Capable Algorithm for Local Dimming RGB Backlight
Authors: Albrecht Marc , Karrenbauer Andreas , Xu Chihao
Published: August 2010

We present an algorithm for efficient calculation of local dimming RGB LED‐Backlight to save power consumption. The algorithm was implemented in hardware to support Full‐HD resolution at a low HW‐ cost. It showed clipping‐free and video‐capable results.
56.2:Distinguished Student Paper: Effects of Localized Warpage and Stress on Chip‐On‐Glass Packaging Induced Light Leakage Phenomenon in 13‐Inch TFT‐LCD
Authors: Chang Chin‐Cheng , Leu Jihperng , Lin Mao‐Hsing , Huang Kun‐Feng
Published: August 2010

Mura defect induced by chip‐on‐glass packaging in 13‐inch LCD‐TFT was investigated using contour measurement and numerical analysis. Excellent correlation between Mura defect and localized warpage/principal stress has been established. Besides, the effects of ACF bonding temperatures and Si chip arrangement on Mura defect were studied and discussed.
65.4: Active Matrix PHOLED Displays on Temporary Bonded Polyethylene Naphthalate Substrates with 180 °C a‐Si:H TFTs
Authors: Loy Doug , Lee Yong Kyun , Bell Cynthia , Richards Mark , Bawolek Ed , Ageno Scott , Moyer Curt , Marrs Michael , Venugopal Sameer M. , Kaminski Jann , Colaneri Nick , O'Rourke Shawn M. , Silvernail Jeff , Rajan Kamala , Ma Ruiqing , Hack Michael , Brown Julie J. , Forsythe Eric , Morton David
Published: August 2010

A low temperature, 180 °C, amorphous Si (a‐Si:H) process on bonded polyethylene naphthalate substrates is discussed and a 4.1‐inch QVGA active matrix (AM) phosphorescent OLED display is demonstrated. The n‐channel thin‐film transistors (TFTs) exhibited saturation mobilities of 0.773 cm2/V‐sec, layer to layer registration distortion less than 10ppm and low defectivity. The efficiency of the OLED display is 39 cd/A at 500 nits.
P‐124: Half V‐Shaped Switching in a Single‐Sided Polyimide FLC Cell with the N‐SmA‐SmC Phase Sequence
Authors: Chiang Chun‐Hung , Wu Jin‐Jei
Published: August 2010

A single‐Sided polyimide ferroelectric liquid crystal (FLC) cell with an inherent asymmetric electrooptic (EO) characteristic was studied. However, its transmittance was too low (< 26%) in practical applications. Therefore, with the help of fields in the cooling duration, the asymmetric EO property could be transformed into half V‐shaped (HV) switching type. The transmittance of bright state was increased by 6% for the cell thickness of 2.7 μm at an applied voltage of 10 volts.
Using native riparian barriers to reduce Giardia in agricultural runoff to freshwater ecosystems
Authors: Winkworth Cynthia L. , Matthaei Christoph D. , Townsend Colin R.
Published: August 2010

Waterway degradation in agricultural settings is caused by direct and diffuse sources of pollution. Waterway fencing focuses on reducing direct faecal contamination, but the extent to which it reduces overland surface runoff of pathogens is unknown. This study evaluated the potential of four riparian treatments to reduce Giardia in saturation excess surface runoff entering the waterway. Treatment 1 comprised exotic pasture grass and weeds that regenerated from bare soil between the fence and the waterway in the absence of cattle grazing and was compared with three others comprising monocultural plantings of New Zealand native grassland plants. Runoff experiments involving Giardia were performed after planting, both prior to and following the summer growing season. Giardia was not detected from any plot prior to cyst addition. In spring the native ‘C. secta’, ‘A. lessoniana’ and ‘C. richardii’ treatments showed significantly greater reductions in Giardia in runoff than the ‘exotic grasses’ treatment, while in autumn the ‘C. richardii’ treatment reduced Giardia more than the ‘exotic grasses/weeds’. A reduction in public health risk should follow from riparian vegetation, whether exotic or native, but with an added benefit in the case of the native tussock grass C. richardii, due to the associated lower runoff rate.
Relationships between the occurrence of Giardia and Cryptosporidium and physicochemical properties of marine waters of the Pacific Coast of Mexico
Authors: Magana-Ordorica Dalia , Mena Kristina , Valdez-Torres Jose B. , Soto-Beltran Marcela , Leon-Felix Josefina , Chaidez Cristobal
Published: August 2010

Untreated sewage has adversely affected the quality of marine recreational waters worldwide. Exposure to marine recreational water with poor microbial quality may pose a threat to bathers. The objectives of this study were to assess the effect of physicochemical parameters on Cryptosporidium and Giardia presence in marine recreational water of Sinaloa, Mexico, by Logistic Regression Analyses. Thirty-two 10-litre water samples were collected from two tourist beaches, Altata and Mazatlan, between November 2006 and May 2007. Water samples were processed by the EPA 1623 method and pH, temperature, salinity and turbidity were also determined. Cryptosporidium and Giardia were present in 71 and 57% of the samples collected from Altata, respectively. In Mazatlan, Cryptosporidium and Giardia were found in 83 and 72% of the samples, respectively. The overall concentration of Cryptosporidium ranged from 150 to 2,050 oocysts/10 L with an average of 581 oocysts/10 L and Giardia ranged from 10 to 300 cysts/10 L with an average of 73 cysts/10 L. The occurrence of both parasites increased in water with decreasing temperatures and increasing turbidity of the water.
Homemade bone charcoal adsorbent for defluoridation of groundwater in Thailand
Authors: Smittakorn Sunisa , Jirawongboonrod Nithat , Mongkolnchai-arunya Surat , Durnford Deanna
Published: August 2010

High levels of fluoride in groundwater are a significant environmental and health problem in Thailand, as in many parts of the world. Small household defluoridators have several advantages over centralized treatment systems. In Thailand, however, use of bone char for water treatment has met resistance because of objectionable taste and odours of the water produced and the social resistance to handling fresh bone. This paper presents a method that uses bone charcoal as an absorbent for removing fluoride from groundwater. The commercially provided boiled bone is burned in a simple homemade furnace that can be constructed, operated and maintained easily by small rural householders. The method to produce the Thai bone char eliminates the odour and objectionable taste and also does not require the user to handle fresh bone, thus eliminating the social resistance. To evaluate the efficacy of the absorbent, batch experiments compare Thai and Indian bone char. Sorption isotherms are fit to the Freundlich and Langmuir equations and the kinetics are modelled using the pseudo first-order Lagergren equation. Results show that the sorption characteristics of Thai bone char compare favourably with the Indian bone char, with approximately 80% of the fluoride removed in both cases.
Nitrification, denitrification and ammonification in point-of-use biosand filters in rural Cambodia
Authors: Murphy Heather M. , McBean Edward A. , Farahbakhsh Khosrow
Published: August 2010

In order to address the United Nations Millennium Development Goal (MDG) target #7 for water and sanitation, the World Health Organization (WHO) has identified point-of-use (POU) water treatment technologies as an option for providing safe water to households. The BioSand filter (BSF) is a commonly used POU system that has been implemented in Cambodia and over 20 countries worldwide. While the health benefits of using a BSF in terms of reduction of diarrheal disease have been fairly well documented, little research has focused on the ability of this technology to treat for other contaminants that could pose health concerns. To address these concerns, a study was developed to evaluate this technology in rural Cambodia in terms of microbiological and chemical quality of the treated water. The study revealed that simultaneous nitrification and denitrification is occurring inside the BioSand filters. Nitrite concentrations in treated water consistently exceeded WHO guidelines. Seventeen of 20 filters on average did not meet the 3.0 mg l−1 NO2− guideline and the combined nitrate-nitrite guideline ratio of 1. Denitrification seemed to predominate when BSFs were fed surface water. In addition, nitrate-ammonification occurred in some filters fed surface water, causing increases in ammonia in treated water.
On-site treatment of domestic wastewater using a small-scale horizontal subsurface flow constructed wetland
Authors: Gikas G. D. , Tsihrintzis V. A.
Published: August 2010

A small-scale horizontal subsurface flow constructed wetland, located in North Greece, was designed and constructed to treat wastewater from a single-family residence. A three-year monitoring program was undertaken to evaluate the performance of this system. The monitoring campaigns were organized every 7 days. Water quality samples were collected at the inlet, at intermediate points (i.e. at the end of each treatment stage) and at the outlet of the system. Temperature, electrical conductivity, pH and DO were measured in-situ with the use of appropriate instruments at the same points of water sample collection. Water samples were analyzed for BOD, COD, TKN, ammonia, nitrate, nitrite, total phosphorus (TP), ortho-phosphate (OP), total suspended solids (TSS) and total coliforms (TC). Mean removal efficiencies for the monitoring period were: 86.5% for BOD, 84.6% for COD, 83.7% for TKN, 82.2% for ammonia, 63.1% for OP, 63.3% for TP, 79.3% for TSS and 99.9% for TC. Furthermore, based on statistical testing, TKN, ammonia and TP removal efficiencies showed dependence on temperature. The paper presents facility description, study details and monitoring results. The study shows that the use of constructed wetlands in wastewater treatment is a good option for single-family residences in rural areas.