bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Coexisting Electron Donor Species on Charge Transfer in Dye-Sensitized Nanocrystalline TiO2 for H2 Evolution under Visible Light
Authors: Maitani Masato M , Zhan Conghong , Huang Ching-Chun , Hu Chi-Chang , Mochizuki Dai , Suzuki Eiichi , Wada Yuji 
Published: November 2012

Abstract
Water splitting under visible irradiation is of significant importance for the ultimate purpose of producing fuel from abundant water and sunlight for a sustainable future society. The efficient photon collection in the visible region and proper construction of the reaction site on the semiconductor surface have been desired and studied to provide an efficient system to create a photoexcited hole–electron pair to proceed toward surface chemical reactions. In this paper, a dye-sensitized nanocrystalline TiO2 colloidal suspension in an aqueous system is applied for H2 evolution under visible light (&gt;390 nm). The efficiency of H2 evolution is strongly influenced by the dye-sensitizers, Ru complex (N719) and porphyrin derivatives, and the combination with coexisting electron donor species, methanol (MeOH) and triethanolamine (TEOA), in the suspension system. The analysis of fluorescence quenching of the porphyrin dye-sensitized nanocrystalline TiO2 in the colloidal suspensions and photoelectrochemical studies of dye-sensitized nanocrystalline TiO2 porous films reveal that the charge-transfer kinetics of the electron injection from the excited dye-sensitizers into TiO2 is strongly influenced by the surroundings, especially the concentration of coexisting electron donor species rather than the pH values of the surrounding solution, resulting in significant differences in the efficiencies of the proton reduction into H2.
γ-Selective Addition to 1,1-Difluoroallenes: Three-component Coupling Leading to 2,2-Disubstituted 1,1-Difluoroalkenes
Authors: Fuchibe Kohei , Ueda Mikiko , Yokota Misaki , Ichikawa Junji 
Published: November 2012

Abstract
1,1-Difluoroallenes underwent γ-selective addition with alkylcopper reagents. The resulting 2,2-difluorovinylcopper intermediates were captured by electrophiles or subjected to palladium-catalyzed coupling to give 2,2-disubstituted 1,1-difluoroalkenes in good yield.
Multicomponent Cascade Reactions for the Synthesis of 2,3-Dihydrobenzofuran Derivatives
Authors: Li Qu-Bo , Hu Xiao-Chun 
Published: November 2012

Abstract
A multicomponent cascade reaction for the synthesis of highly substituted 2,3-dihydrobenzofuran derivatives with moderate to good yields was developed. The synthetic utilities of these 2,3-dihydrobenzofurans were also further explored. Ethyl 2-hydroxy-3-oxo-2,3-dihydrobenzofuran-2-carboxylate and ethyl benzofuran-2-carboxylate were easily obtained from 2,3-dihydrobenzofurans.
Effect of Low-voltage Pulse on Cell Elimination
Authors: Otsuka Hidenori , Okimura Saya , Nagamura Masako , Matsukuma Daisuke , Kutsuzawa Koichi , Matsuda Naoki , Nakashima Tatsuro , Okabe Hirotaka 
Published: November 2012

Abstract
The low electric field application to HeLa cells adhered to electrodes was studied to induce cell death effectively. The low-voltage pulse applied to the electrode was generated with charge and discharge by an originally made circuit. The unique characteristics in this experiment is the charge flow between electrodes, and it causes direct attack of the ions to the cell membrane, leading to complete cell elimination. Viability of cells appreciably decreased with increase in discharge time at a quite low 3 V cm−1 that has not been reported to date.
A Molecular Orbital Study of the Dipole Moment of HF, LiH, and HeH+
Authors: Teramae Hiroyuki , Nagaoka Shin-ichi , Nagashima Umpei 
Published: November 2012

Abstract
The threshold bond distances of electron transfer in the typical heteronuclear diatomic molecules, HF, LiH, and HeH+ have been studied in conjunction with the dipole moments by using ab initio molecular orbital method. The electron transfer begins at 3 Å for HF, 6 Å for LiH, and 4 Å for HeH+, and the dipole moments have their maxima at 1.2 Å for HF, 2.4 Å for LiH, and 0.8 Å after the electrostatic correction for HeH+.
Flexible Silacyclophanes with Two Tricyclic Aromatic Units Linked by Two Disilanyl Pillars
Authors: Nakanishi Waka , Kamata Sho , Hitosugi Shunpei , Isobe Hiroyuki 
Published: November 2012

Abstract
A series of silacyclophanes with two carbazole units linked by two disilanyl pillars were synthesized by a concise one-pot procedure. The step-like structure of disilanyl double-pillared biscarbazole (SiDPBC) in crystals was disclosed by X-ray diffraction analysis. In the solution phase, SiDPBC fluctuated its structure rapidly on the NMR time scale with the aid of the wide-open angles of the two pillars, which was not observed with other congeners possessing tricyclic aromatic units.
Predicting liquefaction of tangier soils by using semiempirical approaches and continuum based modelling
Authors: Touil N. , Khamlichi A. , Dubujet P. , Jabbouri A. 
Published: November 2012

AbstractLiquefaction potential of soils under the risk of seism is usually assessed by using correlation formulas that are based on field tests and historical earthquakes databases. These correlations depend on the site where they were derived. To use them for other sites where seismic history is not available, further investigation is needed. In this work, a one-dimensional modelling of liquefaction phenomenon is performed by using DeepSoil software. The soil data required for simulations were obtained from field tests consisting of core sampling and cone penetration testing. Using reliability analysis, the probability of liquefaction was estimated for sandy soils located in the Moroccan city of Tangier. The obtained results were found to be close to predictions due to Juang semiempirical approach.
An ant colony optimization algorithm-based emergency control strategy for voltage collapse mitigation
Authors: El-Sehiemy R. A. , El Ela A. A. A. , Kinawy A. M. M. , Mouwafia M. T. 
Published: November 2012

Abstract
This paper presents optimal preventive control actions using ant colony optimization (ACO) algorithm to mitigate the occurrence of voltage collapse in stressed power systems. The proposed objective functions are: minimizing the transmission line losses as optimal reactive power dispatch (ORPD) problem, maximizing the preventive control actions by minimizing the voltage deviation of load buses with respect to the specified bus voltages and minimizing the reactive power generation at generation buses based on control variables under voltage collapse, control and dependent variable constraints using proposed sensitivity parameters of reactive power that dependent on a modification of Fast Decoupled Power Flow (FDPF) model. The proposed preventive actions are checked for different emergency conditions while all system constraints are kept within their permissible limits. The ACO algorithm has been applied to IEEE standard 30-bus test system. The results show the capability of the proposed ACO algorithm for preparing the maximal preventive control actions to remove different emergency effects.
Smart Additives for Self-Curing Concrete
Authors: Kovler Konstantin 
Published: November 2012

ABSTRACTSelf-curing, or internal curing (IC), technology has been developed to counteract self-desiccation and autogenous shrinkage of high-strength/high-performance concrete (HSC/HPC), which is considered the "Achilles’ hill" of HSC/HPC [1]. According to ACI [2], IC refers to the process by which the hydration of cement continues because of the availability of internal water that is not part of the mixing water; while the internal water is made available by the pore system in structural lightweight aggregate (LWA) that absorbs and releases water. Recently ACI defined internal curing as “supplying water throughout a freshly placed cementitious mixture using reservoirs, via pre-wetted lightweight aggregates, that readily release water as needed for hydration or to replace moisture lost through evaporation or self-desiccation” [3]. Both definitions address the use of pre-wetted LWA as a self-curing (or internal curing) agent.According to the definition of the RILEM Technical Committee TC-196 [4], IC implies introduction to the concrete mixture a component, which serves as a curing agent. This agent can be either a normal aggregate introduced into the concrete mixture in water-saturated state or a new component (for example, an additive or special aggregate). Similarly to the division accepted in external curing, RILEM TC-196 distinguishes between two categories of internal curing: (a) internal water curing (sometimes called “water entrainment”), when the curing agent performs as a water reservoir, which gradually releases water, and (b) internal sealing, when the curing agent is intended to delay/prevent loss of water from the hardening concrete. Although water-saturated porous aggregate is still the most popular material among IC agents, super-absorbent polymers (SAP), ceramic waste, recycled aggregate and wood-derived products show promising properties. In view of this, self-curing covers not only use of pre-wetted LWA, but also other methods of curing: water curing by means of variety of curing agents introduced in the concrete mix, and also the methods based on internal sealing.The recent achievements in methods and materials for self-curing are reviewed, and the future trends in development of self-curing concrete are discussed.
Efficiency of Limestone Powder in SCC
Authors: Babu K. Ganesh , Sekhar B. Chandra 
Published: November 2012

ABSTRACTSelf-compacting concretes have been of topical interest due to the ease of adoption and the significant savings in compaction efforts particularly at the congested reinforcement locations, in spite of the leak-proof forms required. However, many of the aspects regarding their production with different powder or pozzolanic additions and their corresponding mechanical strength characteristics are not yet fully understood. This paper deals exclusively with the compressive strength characteristics of these concretes incorporating limestone powder as a mineral admixture through the water cement ratio to strength results of concretes reported in literature. The basic idea is to get an idea of the SCCs at the lowest and the highest possible amounts of the limestone powder in it.
In-situ Measurements of Cluster Volume Fraction in Silicon Thin Films Using Quartz Crystal Microbalances
Authors: Kim Yeonwon , Hatozaki Kosuke , Hashimoto Yuji , Seo Hyunwoong , Uchida Giichiro , Kamataki Kunihiro , Itagaki Naho , Koga Kazunori , Shiratani Masaharu 
Published: November 2012

ABSTRACTWe have carried out in-situ measurements of cluster volume fraction in silicon films during deposition by using quartz crystal microbalances (QCM’s) together with a cluster-eliminating filter. The cluster volume fraction in films is deduced from in-situ measurements of film deposition rates with and without silicon clusters using QCM’s. The results show that the higher deposition rate leads to the higher volume fraction of clusters.
Shape-controlled synthesis of silver nanostructures for high-thermal conductivity nanofluids
Authors: Garcia Glorimar , Perales-Perez Oscar , Ahmadi Majid , Guinel Maxime J-F 
Published: November 2012

ABSTRACTA nanofluid is a solid-liquid composite material consisting of a stable suspension of nanometric particles in a conventional refrigerant liquid expected to exhibit enhanced heat transfer properties. Elemental silver (Ag) was selected in this research because of its high electrical and thermal conductivity that are likely to be dependent on the crystal size and shape at the nanoscale. Accordingly, we have synthesized highly monodisperse silver nanowires and nanocrystals by reducing silver nitrate solutions with ethylene glycol in presence of polyvinylpyrrolidone, (PVP). The shape-control in the silver nanostructures was achieved by a proper selection of the type and level of chloride salts, e.g. KCl and CaCl2, and specific PVP/Ag mole ratios in starting solutions. The development of the metal phase was confirmed by X-ray diffractometry. Transmission electron microscopy analyses evidenced the formation of silver nanowires exhibiting a very uniform thickness that could be tuned in the 40-130nm range. UV-vis measurements evidenced the plasmon peak at ∼387nm and clear shoulders at ∼357nm that are indicative of the formation of elongated nanostructures.
Passivation of Silicon Surfaces by Formation of Thin Silicon Oxide Films Formed by Combination of Induction-Coupled Remote Oxygen Plasma with High Pressure H2O Vapor Heat Treatment
Authors: Abe H. , Yoshidomi S. , Nagatomi Y. , Hasumi M. , Sameshima T. 
Published: November 2012

ABSTRACTWe report formation of thin silicon oxide films on the silicon surfaces by combination of oxygen radical and high pressure H2O vapor heat treatment for passivation of silicon surfaces at a low temperature. Oxygen plasma was generated by 13.56 MHz radio frequency induction-coupled remote plasma with mixed gases of O2 and Ar at 2 sccm, 2x10-2 Pa and at a power of 50 W. Oxygen radical was produced from the plasma via a metal mesh closing plasma in the reactor. The top surfaces of 20 Wcm n-type silicon substrates with the rear surface coated by thermally grown SiO2 layers were exposed by oxygen radical from 1 to 5 min to oxidize the silicon surface. The samples were subsequently annealed with 9.0x105 Pa H2O vapor heat treatment at 260oC for 3 h. The effective minority carrier lifetime estimated using photo-induced carrier microwave absorption system in the case of 635 nm light illumination at 1.5 mW/cm2 to the top surface increased from 1.3x10-4 to 5.1x10-4s as the oxygen radical treatment duration increased from 1 to 5 min. The recombination velocity decreased from 380 to 90 cm/s. 500 kHz capacitance response with bias gate voltages characteristics of metal oxide semiconductor structure resulted in the effective oxide thicknesses (EOT) ranging from 1.3 to 1.7 nm. These results indicate a capability of thin oxide formation and effective passivation of silicon surfaces at a low temperature.
Rapid Epitaxial Growth of Si and SiGe Mono-Crystalline Films on Silicon-on-Glass Substrates by Reactive CVD Using SiH4, GeH4, and F2
Authors: Noge Hiroshi , Okada Akira , Chuang Ta-Ko , Couillard J. Greg , Kondo Michio 
Published: November 2012

ABSTRACTWe have succeeded in the rapid epitaxial growth of Si, Ge, and SiGe films on Si substrates below 670 ºC by reactive CVD utilizing the spontaneous exothermic reaction between SiH4, GeH4, and F2. Mono-crystalline SiGe epitaxial films with Ge composition ranging from 0.1 to 1.0 have been successfully grown by reactive CVD for the first time.This technique has also been successfully applied to the growth of these films on silicon-on-glass substrates by a 20 - 50 ºC increase of the heating temperature. Over 10 μm thick epitaxial films at 3 nm/s growth rate are obtained. The etch pit density of the 5.2 μm-thick Si0.5Ge0.5 film is as low as 5 x 106 cm-2 on top. Mobilities of the undoped SiGe and Si films are 180 to 550 cm2/Vs, confirming the good crystallinity of the epitaxial films.
Low-temperature Plasma Processing of Micro- and Nanostructured Materials for Biomedical Applications
Authors: Nagatsu Masaaki , Bekarevich Roman V. , Balmakov Alexei , Motrescu Iuliana , Ogino Akihisa , Murakawa Akiko , Park Enoch Y. 
Published: November 2012

ABSTRACTWe develop a plasma processing technique for modifying the surface properties of micro- and nanostructured materials for biomedical applications. We also investigate the physical and chemical roles of the plasma in modifying the surfaces of micro- and nanostructured materials such as magnetic nanoparticles (MNPs), carbon nanotubes (CNTs), nanophosphors, and biomolecules for various biomedical applications. We introduced amino groups onto the surfaces of graphite-encapsulated iron compound nanoparticles using a low-pressure Ar plasma pre-treatment and ammonia plasma post-treatment followed by immobilization of biomolecules, such as dextran and N-acetyllactosamine (LacNAc). The present technique was also used to introduce amino groups onto CNT dot arrays grown on Si substrates for use in biochip sensors.
3-D optical modeling of single and multi-junction thin-film silicon solar cells on gratings
Authors: Isabella O. , Solntsev S. , Caratelli D. , Zeman M. 
Published: November 2012

ABSTRACTThree-dimensional (3-D) optical modeling based on Finite Element Method of single, double, and triple junction thin-film silicon solar cells is presented. The combination of front periodic gratings with optimal geometrical parameters and rear ZnO/Ag reflector constitutes an efficient light trapping scheme for solar cells in superstrate (pin) configuration. The application of optimized trapezoidal 1-D and 2-D gratings resulted in 25.5% (1-D case) and 32.5% (2-D case) increase in photo-current density with respect to the flat solar cell. The application of inverted pyramidal 2-D gratings in double and triple junction silicon solar cells with very thin absorber layers resulted in a photo-current density > 11 mA/cm2 and > 9 mA/cm2, respectively.
Multivariate Analysis of a-SiGe:H Multispectral Photodiodes for Proper Band Selection
Authors: Merfort Christian , Bablich Andreas , Schwaneberg O. , Watty Krystian , Boehm Markus 
Published: November 2012

ABSTRACTThe demand for low cost and disposable devices has driven the development of intelligent photodiodes, especially multispectral photodiodes that were first manufactured by Rieve et al. in 2000 [1]. The most remarkable feature of these devices is the voltage-controlled spectral response. In this paper we present a-SiGe:H based bias sensitive ni3p photodiodes that have been fabricated successfully in a low temperature PECVD process. Multispectral diodes based on ni3p structures make use of an intrinsic layer divided into three regions. Further subdivision of the i-layer into different collection regions is the key to an unequivocal optical detection. In addition to the a-SiGe:H multispectral photodiodes developed at the IMT, there is an inestimable wealth of different sensor approaches that has been optimized for different applications. To optimize the separation of secondary colors (i.e. spectral signatures) it is necessary to separate only those response curves (i.e. bands) with a very high information density [2, 3]. In our case, samples of whitish powder suspected to be dangerous or illegal must be unequivocally characterized. There is need for an application specific band selection method by which various sensors can be compared and evaluated. Unfortunately it is not sufficient to optimize the spectral response only as discussed in [4]. The requirements for measuring surroundings and the mechanical handling of all parameters together form a multivariate data set. Examined were in fact more than 5,000 measurement setup combinations, fictional and real, each considering 10 parameters that partially influence each other. The influence of all these parameters has to be examined, with the awareness of multivariate analysis [5].
Effects of Hydration on Nanoscale Structural Morphology and Mechanics of Individual Type I Collagen Fibrils
Authors: Wallace Joseph M. , Harding Chad , Kemp Arika 
Published: November 2012

ABSTRACTType I collagen is one of the most vital proteins in our bodies and serves a number of structural roles. Despite collagen’s importance, little is known about its nanoscale morphology in tissues and how morphology relates to mechanical function. This study directly probes nanoscale structure and mechanics in collagen as a function of hydration utilizing atomic force microscopy investigations of the mouse tail tendon. We demonstrate that collagen morphology and mechanical properties at the nanoscale change with dehydration, indicating that hydration is a factor which must be considered when performing studies at any length scale in collagen-based tissues. Studies are underway to further investigate this phenomenon and to determine how these properties change with disease in tendon and other Type I collagen-based tissues.
Selective Killing of Ovarian Cancer Cells through Induction of Apoptosis by a Nonequilibrium Atmospheric Pressure Plasma
Authors: Tanaka Hiromasa , Iseki Sachiko , Nakamura Kae , Hayashi Moemi , Kondo Hiroki , Kajiyama Hiroaki , Kano Hiroyuki , Kikkawa Fumitaka , Hori Masaru 
Published: November 2012

ABSTRACTTwo independent ovarian cancer cell lines and fibroblast controls were treated with nonequilibrium atmospheric pressure plasma (NEAPP). Most ovarian cancer cells were detached from the culture dish by continuous plasma treatment to a single spot on the dish. Next, the plasma source was applied over the whole dish using a robot arm. In vitro cell proliferation assays showed that plasma treatments significantly decreased proliferation rates of ovarian cancer cells compared to fibroblast cells. FACS and Western blot analysis showed that plasma treatment of ovarian cancer cells induced apoptosis. NEAPP could be a promising tool for therapy for ovarian cancers.
Nano-Crystalline Si Based Alloy (nc-SiXY) with Band Gap of 1.5 eV as the Solar Cell Absorber Layer Fabricated by VHF-PECVD Technique
Authors: Zhu Feng , Hu Jian , Matulionis Ilvydas , Gallon Josh , Madan Arun 
Published: November 2012

ABSTRACTWe describe the properties of nano-crystalline silicon based alloy (nc-SiXY) prepared by a very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD) technique with silane (SiH4) and XY gas mixtures and diluted in hydrogen (H2) at low deposition temperature. Varying the gas ratio among SiH4, H2 and XY gasses could alter the optical bandgap and structure. The nc-Si films with high crystalline volume fraction were first prepared, and then the XY gasses were added in order to tune the microstructure and opto-electronic properties of this nano-crystalline silicon based alloy. We have characterized the materials using UV-VIS-NIR, Raman, Constant Photocurrent Method (CPM), dark- and photo-conductivity. As XY gas flows were increased, the optical bandgap of nc-SiXY films increased, while its crystalline volume fraction and conductivity decreased. With proper control of the silane concentration, XY/SiH4 gas ratio, and deposition pressure, we have fabricated the nc-SiXY film with optical bangap of about 1.5eV. Applying this material as the absorber layer in p-i-n devices with configuration of textured ZnO/nc-p+/nc-SiXY/a-n+/Ag, the efficiency is 7.25% (Voc=0.616V, Jsc=17.69mA/cm2, FF= 0.666) with thickness of ∼0.8μm.
Effect of Doping on Nanowire Morphology during Plasma-assisted Chemical Vapor Deposition
Authors: Lohn Andrew J. , Norris Kate J. , Cormia Robert D. , Coleman Elane , Tompa Gary S. , Kobayashi Nobuhiko P. 
Published: November 2012

ABSTRACTMorphologies of silicon nanowires grown by plasma-assisted metalorganic chemical vapor deposition were studied in the presence of various dopant precursors. The varied precursors affected the axial and radial growth rates over orders of magnitude where triethylborane showed the strongest enhancements for both axial and radial growth, and triethylarsenic and triethylantimony retarded axial growth. Native oxide thickness is also shown to depend strongly on doping condition resulting in increased oxide thicknesses for increased carrier concentration, using shifts in the measured binding energy of the silicon 2p3/2 state as a proxy for carrier concentration.