bluuebunny/crossref_metadata_2025 huggingface dataset:
Review on Air Cathode in Li-Air Batteries
Authors: Zha Zhaoru , Shen Cai , Wang Deyu , Han Weiqiang
Published: November 2013

Lithium-air (Li-air) battery is a promising electrochemical system with unprecedented high energy density. However, many problems and challenges prevent its wide scale application and commercialization. Low oxygen diffusion rates and large voltage gap are two of the main problems in Li-air battery. These two problems are related to the materials used in the air cathode such as porous carbon materials and metallic catalysts. This review seeks to discuss various materials used in the air cathode for Li air batteries. Mechanism of reaction in air cathode will be elucidated and discussed.
Interconnection of a Wind Driven DC Machine with the Power Utilities Grid
Authors: Taleb Maamar
Published: November 2013

A wind driven DC machine is interconnected with the power utilities grid. The wind driven DC machine is operated in the regenerative mode and that is to guaranty the extraction of the real power from the wind driven generator and inject it into the power grid. This is done through the use of a single phase full wave controlled converter operating in “ an inverter mode of operation”. At any pretended surrounding weather conditions, maximum extraction of power from the renewable energy source (ie. Wind energy source) is targeted. This is done through the realization of a self-adjusted firing angle controller responsible of triggering the semiconductor elements of the controlled converter. An active power filter is shunted with the proposed setup to guaranty the sinusoid quality of the power utilities line current. The overall performance of the proposed system has been simulated in MATLAB/SIMULINK environment. Quite satisfactory and encouraging results have been obtained.
The Impact of Gasfier Stoves Use on Socio-Economic and Environment in Tanzania: The Case of Arusha and Moshi Municipalities
Authors: Mwakaje Agnes Godfrey
Published: November 2013

This study examined the socio-economic and environmental impact of the adoption of gasfier stoves by households in Arusha and Moshi towns in Tanzania. A total of 55 respondents were selected purposely from the gasfier stoves. For comparative purposes another 55 charcoal users were selected randomly for interview making a total sample of 110. There were also focus group consultations and key informant interviews. Structured and semi-structured questionnaires were used to collect data, which were analysed using the Statistical Package for Social Sciences.
The results show that the respondents who were using gasfier stoves had significant reduction (p=0.001) in the cost of energy for cooking compared to charcoal stove users by spending only T.shs 13,396 per month compared to T.shs 36,932 for charcoal users. The use of gasfier stoves also had a positive impact on the environment. Findings show that by using gasfier stoves 15.4 ha were saved from deforestation per annum and about 365.4.tonnes of carbon were saved for sequestration an act that reduces carbon emissions and global warming.
Nevertheless, despite the impressive performance of gasfier stoves for cooking, the rate of adoption has remained low. The main reason for this was reported to be the high price, poor quality of the pellets and unfriendly usability. The adoption of gasfier stoves could only be enhanced by addressing these constraining factors.
Latent Heat Storage with Phase Change Materials (PCMs)
Authors: Zhang H. L. , Baeyens J. , Degrève J. , Pitié F.
Published: November 2013

Latent heat thermal energy storage with phase change materials (PCMs) is attractive since providing a high energy density storage due to the phase change by solidification/melting at constant temperature. Relative to sensible heat energy storage systems, latent heat storage with PCMs requires a smaller weight and volume of material for a given amount of captured/stored energy, and has the capacity to store heat of fusion at a constant or nearly constant temperature, thus maintaining a high and constant temperature difference between the heat exchanging surface and the PCMs.
The present review paper will summarize the required properties of PCMs, with their respective advantages and disadvantages; the current state of development and manufacturing; the development of PCM applications, including their incorporation into heat exchangers, insertion of a metal matrix into the PCM, the use of PCM dispersed with high conductivity particles. PCM uses will be illustrated through some case-studies.
Role of PVA Flakes in Promoting Self-Degradation of Sodium Metasilicate-Activated Cement under a Hydrothermal Environment at 150°C
Authors: Sugama T. , Pyatina T. , Muraca A.
Published: November 2013

We investigated the effect of flakes of polyvinyl alcohol (PVA) on the self-degradation of sodium metasilicate (SMS)-activated slag/Class C fly ash cement, which is used as temporary sealer for fractures in Enhanced Geothermal System (EGS) wells under a hydrothermal environment at ³150°C and at pressure of 1000 psi. The reactions between PVA and SMS dissolved in an aqueous medium at 85°C led to the formation of a colloidal hydroxylated silicate-cross-linked PVA gel in the cement body. This gel-incorporated cement had a compressive strength >2000 psi, so ensuring that it adequately plugs the fractures. Increasing the hydrothermal temperature to ³150°C triggered the transformation of the gel into a sol. This in-situ gel®sol phase transition played a pivotal role in promoting the cement’s self-degradation because of the extensive spreading of sol in the cement body, and its leaching from the cement. In contrast, when gel was dry heated at ³150°C, the gel®xerogel phase transformation engendered the molecular fragmentation of PVA. This fragmentation yielded polysilicate cross-linked PVA derived from the combination of extended-chain scission, carboxylation and condensation, so that it no longer served as a self-degrading promoter of cement.
Biomass Production for Energy in India: Review
Authors: Hegazy Rashad A.
Published: November 2013

This paper presents a general view about biomass production in India and its potential energy for use in different fields. India has tremendous potential for energy generation through biomass and its residues. Biomass energy is normally produced from firewood, agricultural residues such as bagasse, crop stalks, animal dung and wastes generated from agro-based industries. With the estimated and predicted values, the generating power from the surplus biomass in India was significant and it will continue to be more effective in future. Residue use as a fuel in India is estimated to be 216 Mt as projected value in 2010, recently, around 605 MW of electricity is being produced from biomass firing and 720 MW from cogeneration activities for residue. About 185 Mt (40%) of the dung collected is used as fuel in cook stoves. The potential for biogas production annually is 8750 million m3 from 251 Mt of dung. The amount of fuel-wood consumption during year 2004 was 205 million tonnes used as fuel for traditional cook stoves with low efficiency, 16 Mt used in industrial sector producing 10 PJ, and it was estimated that the production of fuel wood and charcoal increased to the rate of 1.98 per cent per annum. The total quantity of solid wastes generated in larger towns and cities has been estimated at 40 Mt in 2001, and in 2005 the average MSW generation in overall India was approximately 100,000 Mt/day. For the wastewater in India, in 2010, the energy estimated to be around 3929.8 TJ as energy value of CH4.
Production and Characterization of Biodiesel from Allamanda Cathertica Oil
Authors: Evans C. Egwim , Ibrahim Z.A. , Onwuchekwa Praise
Published: November 2013

The gradual depletion of world petroleum reserves and the impact of environmental pollution due to increasing exhaust emissions have necessitated the urgent need to develop alternative energy resources, such as biodiesel fuel. Vegetable oil is a promising feedstock because it has several advantages; it is renewable and environmental friendly. The present study involves extraction of oil from Allamanda cathertica seed (Allamanda), Azadarachta indica and Jatropha caucus; conversion of the oil into biodiesel and the characterization of the methyl ester. Transesterification of the different feed stocks was conducted using sodium methaoxide (NaMt), sodium ethaoxide(NaEt), potassium methaoxide (PMt) and potassiumethaoxide (PEt) as catalysts, using a range of reaction temperatures (45, 50, 55, 60 and 65OC) and different rates of stirring. Result showed that Allamanda seed produced 54% oil yield using mechanical extraction. The biodiesel yield was 97% using NaMt and NaEt as catalysts, while azadarachta oil gave 95% yield with PEt catalyst alone. Jatropha oil gave a yield of 70% biodiesel with all the catalysts used. The yield of biodiesel from Allamanda oil with respect to temperature were 63, 88, 94, 46 and 20% respectively. Characterization of the biodiesel produced from Allamanda oil compared favorably with the ASTM standards, viscosity 5.4, flash point 115OC, refractive index 1.4756 and energy value 35.0MJ/L. The GCMS analysis of Allamanda methyl ester showed a range of 10 different methyl esters which includes hexadecanoic acid (24%), linoleic acid (14.8%), 13-Decosenoic acid (35.3%), 9-Octadecanoic acid (13.5%). The work concludes that allamanda oil could be a good and alternative feedstock to the edible feedstocks currently in use for biodiesel production.
Cuisiner en bordure de la piste
Authors: Jarvenpa Robert
Published: November 2013

Dans le sillage des récents changements politico-économiques dans le nord du Canada, des équipes mobiles de chasseurs-trappeurs et pêcheurs chipewyans (Dene) subissent de nos jours de longues périodes d’isolement, loin des villages où vivent et travaillent les autres membres de leurs familles. Dans ce contexte, les hommes chipewyans sont confrontés à un dilemme structurel. Ils doivent choisir entre reproduire, abandonner ou modifier les savoir-faire hautement spécialisés du traitement et de la transformation de la nourriture qui étaient habituellement réalisés par les femmes, dans les campements familiaux saisonniers et nomades des années précédentes. L’analyse se concentre sur la préparation des repas et les pratiques de dîner dans les camps forestiers exclusivement masculins des dernières années, et sur la manière dont ces comportements reflètent de pénibles changements dans les relations entre genres. Paradoxalement, tandis que les hommes ont gardé de nombreux ingrédients historiques et familiers dans leur régime alimentaire, l’absence des savoir-faire des femmes dans la préparation de ces aliments confère à la cuisine contemporaine des hommes une place potentiellement ambiguë : une nourriture de la forêt, ou de la piste, qui n’est plus pleinement chipewyane.
Fêtes traditionnelles et festivals glocalisés aux Marquises
Authors: Riley Kathleen C.
Published: November 2013

Cet article commence par un bref survol des sources ethnohistoriques couvrant la production, la distribution, la préparation, et la consommation de la nourriture aux îles Marquises depuis l’époque des contacts réguliers avec les européens au XVIIIe siècle jusqu’aux différentes vagues d’expériences de la globalisation (exploration, commerce, colonisation, christianisation, éducation, tourisme et médias internationaux). Il montre comment les réactions locales à ces forces globales ont produit une série de formes alimentaires syncrétiques – ordinaires et rituelles – dont l’intérêt analytique dépasse la simple dimension ethnographique, puisqu’elle permet de comprendre de façon théorique la manière dont ces communautés utilisent la dimension sémiotique et sensible de la nourriture pour forger des identités hybrides. L’analyse met au point premièrement comment les formes alimentaires « traditionnelles » ont été maintenues et réinventées et deuxièmement comment elles ont été déployées lors des fêtes et festivals glocalisés – domestiques et internationaux – et plus particulièrement ceux associés depuis environ 35 ans avec un mouvement de renouveau culturel aux îles Marquises.
Anthroposophic Medicine: An Integrative Medical System Originating in Europe
Authors: Kienle Gunver S. , Albonico Hans-Ulrich , Baars Erik , Hamre Harald J. , Zimmermann Peter , Kiene Helmut
Published: November 2013

Anthroposophic medicine is an integrative multimodal treatment system based on a holistic understanding of man and nature and of disease and treatment. It builds on a concept of four levels of formative forces and on the model of a three-fold human constitution. Anthroposophic medicine is integrated with conventional medicine in large hospitals and medical practices. It applies medicines derived from plants, minerals, and animals; art therapy, eurythmy therapy, and rhythmical massage; counseling; psychotherapy; and specific nursing techniques such as external embrocation. Anthroposophic healthcare is provided by medical doctors, therapists, and nurses. A Health-Technology Assessment Report and its recent update identified 265 clinical studies on the efficacy and effectiveness of anthroposophic medicine. The outcomes were described as predominantly positive. These studies as well as a variety of specific safety studies found no major risk but good tolerability. Economic analyses found a favorable cost structure. Patients report high satisfaction with anthroposophic healthcare.
Gender Differences among Children with Autism Spectrum Disorder: Differential Symptom Patterns
Authors: Baker Sidney M. , Milivojevich Andrew
Published: November 2013

The gender ratio among children in the autism spectrum of more than four boys to every girl is widely recognized. The authors present an analysis of gender differences among 79 482 symptoms and strengths in 1495 boys and 336 girls aged 2 to 18 years from parent-identified autistic children reported to a structurally novel anonymous parent-entered online database, Autism360. The data reveal differences that provide previously undetected clues to gender differences in immune and central nervous system and gastrointestinal functional disturbances. Together with published observations of male/female differences in inflammation, oxidative stress, and detoxication, these findings open doors to research focusing on gender physiology as clues to etiologic factors in autism. This study exemplifies a research method based on a large, detailed, patient-entered, structured data set in which patterns of individual illness and healing may answer collective questions about prevention and treatment.
The role of Cdc42 and Gic1 in the regulation of septin filament formation and dissociation
Authors: Sadian Yashar , Gatsogiannis Christos , Patasi Csilla , Hofnagel Oliver , Goody Roger S , Farkašovský Marian , Raunser Stefan
Published: November 2013

Septins are guanine nucleotide-binding proteins that polymerize into filamentous and higher-order structures. Cdc42 and its effector Gic1 are involved in septin recruitment, ring formation and dissociation. The regulatory mechanisms behind these processes are not well understood. Here, we have used electron microscopy and cryo electron tomography to elucidate the structural basis of the Gic1-septin and Gic1-Cdc42-septin interaction. We show that Gic1 acts as a scaffolding protein for septin filaments forming long and flexible filament cables. Cdc42 in its GTP-form binds to Gic1, which ultimately leads to the dissociation of Gic1 from the filament cables. Surprisingly, Cdc42-GDP is not inactive, but in the absence of Gic1 directly interacts with septin filaments resulting in their disassembly. We suggest that this unanticipated dual function of Cdc42 is crucial for the cell cycle. Based on our results we propose a novel regulatory mechanism for septin filament formation and dissociation.
Dependence of Field-Effect Mobility of Graphene Grown by Thermal Chemical Vapor Deposition on Its Grain Size
Authors: Yagi Katsunori , Yamada Ayaka , Hayashi Kenjiro , Harada Naoki , Sato Shintaro , Yokoyama Naoki
Published: November 2013

Graphene was synthesized on a Cu film by chemical vapor deposition (CVD) and its grain size was analyzed by using dark-field transmission electron microscopy. The grain size was mainly controlled by changing the partial pressure of hydrocarbons in H2/Ar. The grain size increased as the partial pressure of C2H4decreased, but eventually leveled off. The size saturation may be related to the long growth time at a low partial pressure. It was also revealed that growth using CH4provided graphene with larger grain sizes than that using C2H4at the same partial pressure. Back-gate transistors were then fabricated using graphene with various grain sizes, and the dependence of field-effect mobility on the grain size was investigated. The mobility roughly scales with the grain size, but the intergrain angles and/or small holes at grain boundaries also seem to affect the carrier mobility. It was also found that low mobility was often caused by fractures and/or wrinkles in graphene channels.
Effect of Plasma-On Time on the Axial Distribution of Film Thickness in Internal Diamond-Like Carbon Coating with Microwave-Excited High-Density Plasma
Authors: Matsui Ryosuke , Kousaka Hiroyuki , Umehara Noritsugu
Published: November 2013

We demonstrated source gas depletion in our proposed method for internal diamond-like carbon (DLC) coating with microwaves by using high-speed camera imaging of the emission from Ar atoms and C2dimers during DLC coating. Then, we investigated the effect of the plasma-on time on the axial distribution of the film thickness, hardness, and other properties. The axial variation in DLC coated inside a 1/4-in. stainless steel tube 50 mm in length was greatly reduced from 14% with a plasma-on timeTon= 3.2 ms and a plasma-off timeToff= 96.8 ms in our previous work to 2% withTon= 1.6 ms andToff= 98.4 ms in this work. The coating conditions except forTonandToffwere the same in both experiments. The decrease in the DLC film hardness with increasing plasma-on time was confirmed and is ascribed to a decrease in the film density and number of sp3carbons in the film.
Highly-Crystallized Ge:H Film Growth from GeH4 Very High Frequency Inductively-Coupled Plasma: Crystalline Nucleation Initiated by Ni Nanodots
Authors: Makihara Katsunori , Gao Jin , Sakaike Kouhei , Hayashi Shohei , Deki Hidenori , Ikeda Mitsuhisa , Higashi Seiichiro , Miyazaki Seiichi
Published: November 2013

We prepared Ni nanodots (Ni-NDs) by exposing ultrathin Ni films to very high frequency inductively-coupled plasma (VHF-ICP) of pure H2 without any external heating and demonstrated the feasibility of introducing Ni-NDs for subsequent Ge film growth with high crystallinity. A ∼2.0-nm-thick Ni film/quartz was exposed to H2 plasma generated by inductive coupling with an external single-turn antenna connected to a 60-MHz power generator, and a Ge film was subsequently grown from GeH4 VHF-ICP. When the Ge film was grown on Ni-NDs from GeH4 VHF-ICP at 250 °C, the growth of highly crystallized Ge films with crystallinity as high as 95% at a rate as high as ∼15 nm/s, being ∼2 times higher than the rate obtained by VHF-ICP without Ni-NDs, was realized without an amorphous phase near the Ge film/quartz substrate interface. This result is attributed to heat generation due to the efficient recombination of atomic hydrogen on the Ni surface and heat transfer from the NDs to the precursors for the Ge film adsorbed on the Ni-NDs at the initial stage of VHF-ICP from GeH4 diluted with H2 to initiate crystalline nucleation and growth.
Characteristics of Crystalline Silicon/Si Quantum Dot/Poly(3,4-ethylenedioxythiophene) Hybrid Solar Cells
Authors: Uchida Giichiro , Wang Yuting , Ichida Daiki , Seo Hyunwoong , Kamataki Kunihiro , Itagaki Naho , Koga Kazunori , Shiratani Masaharu
Published: November 2013

Here, we report the characteristics of a novel organic/inorganic hybrid photovoltaic device using a Si quantum dot (QD) layer synthesized by multi-hollow discharge plasma chemical vapor deposition. The hybrid device has a p–i–n structure, which consists of a crystalline Si (c-Si) substrate, a Si QD layer, and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). We have examined the absorption coefficient and photoconductivity of Si QD layers, and confirmed electricity generation from Si QD layers. We have measured the current–voltage characteristics and incident photon-to-current conversion efficiency (IPCE) of c-Si/Si QD/poly(3,4-ethylenedioxythiophene) (PEDOT) hybrid solar cells. This hybrid device shows an energy conversion efficiency of 2.84%, a short-circuit current of 6.84 mA/cm2, an open-circuit voltage of 0.73 V, and a fill factor of 0.58. A high IPCE value of 82.8% is obtained at a short wavelength of 460 nm.
Tooth Whitening Effects by Atmospheric Pressure Cold Plasmas with Different Gases
Authors: Choi Hye-sook , Kim Kyoung-Nam , You Eun-Mi , Choi Eun-Ha , Kim Yong-Hee , Kim Kwang-Mahn
Published: November 2013

The aim of the present study was to investigate the effects of atmospheric pressure cold plasma with different gases on external tooth bleaching. After 10 min treatment, the air (50%) + oxygen (50%) group shows a remarkable color change (ΔE*), and nitrogen and air groups indicate some color change, although not as much as that shown by the air + oxygen group. Also, the argon group shows the least amount of color change among the various gases in this experiment. Atomic oxygen species exists during this tooth bleaching as determined by optical emission spectroscopy. Hence, atmospheric pressure cold plasma treatment could significantly accelerate the tooth bleaching process owing to this atomic oxygen species, and the intensity of tooth bleaching depends on the type of gas in the cold plasma.
Effect of Atomic-Layer-Deposition Method on Threshold Voltage Shift in AlGaN/GaN Metal–Insulator–Semiconductor High Electron Mobility Transistors
Authors: Ozaki Shiro , Ohki Toshihiro , Kanamura Masahito , Okamoto Naoya , Kikkawa Toshihide
Published: November 2013

We have investigated the mechanism for threshold voltage (V
th) shift of AlGaN/GaN metal–insulator–semiconductor high electron mobility transistors (MIS-HEMTs) for power applications. In this study, atomic layer deposited (ALD)-Al2O3 was used in AlGaN/GaN MIS-HEMTs as gate insulator films, and we focused on plasma-induced damages at the GaN/Al2O3 interface, when O2 plasma was used as the oxidant source for the ALD method. We clarified that the deep trap sites which were located around 2.58–3.26 eV from the conduction band edge were generated in the oxidized-GaN layer at the GaN/Al2O3 interface due to plasma-induced damages, and this caused the V
th shift when using O2 plasma. Therefore, we controlled the initial oxidant source, and demonstrated the reductions in the V
th shift and the gate leakage current by applying hybrid–Al2O3 structure (lower H2O vapor–Al2O3/upper O2 plasma–Al2O3) for AlGaN/GaN MIS-HEMTs.
Effects of Substrate Temperature on Properties of Amorphous InxGa1-xN Films Deposited by Reactive Radio Frequency Sputtering
Authors: Suzuki Toshimasa , Hibino Shun , Katayama Ruichi , Kato Yoshinori , Ohashi Fumitaka , Itoh Takashi , Nonomura Shuichi
Published: November 2013

Amorphous indium gallium nitride (a-In
x
Ga1-x
N) films were deposited at various substrate temperatures T
S by simultaneous reactive rf-magnetron sputtering using GaN and InN targets. The nitrogen composition ratio increased with an increase in T
S, and became almost the same as the stoichiometry ratio at a T
S above 100 °C. In the X-ray diffraction patterns of the films deposited at a T
S below 200 °C, no perceivable peaks assigned to crystalline In
x
Ga1-x
N were found. In those deposited at a T
S above 300 °C, however, small broad peaks assigned to crystalline In
x
Ga1-x
N were observed. The dark conductivity σd increased with an increase in T
S. On the other hand, the photoconductivty σp increased with an increase in T
S below 200 °C and a large change in σp was not obtained at a T
S above 300 °C. The photosensitivity σp/σd showed its maximum (1175) at a T
S of 200 °C.
Mn-Doped Zn2SiO4 Thin Film with Green Fluorescence Enhanced by Ag Nano Island Surface Plasmon Effect
Authors: Peng Kun-Cheng , Lin Yi-Chung , Liu Shiu-Jen , Chen Tai-Er , Lee Chun-Ying
Published: November 2013

20–100 nm thin films of silver were first deposited on quartz glass by magnetron sputtering. These specimens were then annealed at 500 °C for 15 min by rapid thermal annealing (RTA), which might change the silver films into having a morphology of nano islands. Subsequently, a thin film of Mn-doped ZnO was deposited on the above specimens in a sputtering system. These specimens were removed from the sputtering system and annealed again in an atmospheric furnace at 1200 °C for 2 h. By X-ray diffraction (XRD) analysis, the annealed samples were identified as Mn-doped Zn2SiO4 crystals. Furthermore, photoluminescence (PL) measurement showed the 530 nm (green light) fluorescence. The silver nano islands embedded in the Mn-doped Zn2SiO4 crystals tended to show an increase in PL intensity in the following order and in increase rate composed with their pristine Mn-doped Zn2SiO4 counterpart: 100 nm Ag (-0.33%), 50 nm Ag (-0.02%), 20 nm Ag (87.4%), 40 nm Ag (124.3%), and 30 nm Ag (168.5%). Accordingly, the plasmon effect may lead to the enhancement of fluorescence, and the size of silver nano islands determines the increase rate.
Field Emission Properties of Spiral Pattern by Screen Printing
Authors: Tsai Woo-Hu , Chang Chih-Chieh , Wu Hsin-Ju
Published: November 2013

A carbon-nanotube-based flat-panel light unit with an aluminum metal anode and an innovative spiral emitter pattern was fabricated in this study. In comparison with roundness and stripe cathode structures, the results show that the structure we proposed has excellent emission performance, namely, high field emission current, no unexpected arcing, high illumination, and good uniformity. Moreover, an emission current density of 5.5 mA/cm2under an electric field of about 2.9 V/µm, and a luminance of 21700 cd/m2were demonstrated.
Electrochemical Behavior of CoNiCrAlY/ZrO2–Y2O3 Coated Layers with Atmospheric Pressure Plasma Technology in Seawater
Authors: Kim Seong-Jong , Woo Yong-Bin , Lee Seung-Jun , Jeong Jae-Yong
Published: November 2013

Application of surface treatment has become common for protecting machine parts from oxidation, abrasion and corrosion induced by external environment. In particular, thermal spraying techniques are widely employed to improve wear, corrosion and thermal resistance. And compared to other methods they are simple and cost effective. However, the presence of porosity in the thermal spray coating can be highly detrimental because it provides access to penetration of corrosive matters, lowering corrosion resistance. Therefore, this research evaluate the electrochemical behavior under marine environment for aluminum–bronze alloy coated with MCrAlY and yttria-stabillized zirconia (YSZ) by atmospheric pressure plasma (APP) coating technology. Further application of carbon-based sealer removed voids and defects in the coating. The result reveled that, in case the voids and defects are completely removed, excellent corrosion resistance can be archived by application of good coating material along with formation of compact sealing layer.
Growth Behavior of Ga-Doped ZnO Thin Films Deposited on Au/SiN/Si(001) Substrates by Radio Frequency Magnetron Sputtering
Authors: Seo Seon Hee , Kang Hyon Chol
Published: November 2013

This paper reports the growth behavior of Ga-doped ZnO (ZnO:Ga) thin films deposited on Au/SiN/Si(001) substrates by radio-frequency magnetron sputtering. The microstructures of the overgrown ZnO:Ga thin films were investigated by performing X-ray diffraction, scanning electron microcopy, and transmission electron microscopy analyses. It was confirmed that the growth process proceeds through three stages. In the first stage, nano-scale ZnO:Ga islands were grown on the SiN layer, while a fairly continuous flat structure was formed on the Au nanoparticles (NPs). In the second stage of the growth process, ZnO:Ga domains with different growth orientations, depending strongly on the crystalline planes of the host Au NPs, were nucleated. These domains then grew at different rates, resulting in a change in the morphology from the initial shape reflecting that of the Au NPs to a sunflower-type shape. In the final stage, columnar growth with a preferred (0002) orientation along the surface normal direction became dominant.
Control of Magnetic Properties of Carbon Nanotubes Filled with Iron
Authors: Sato Hideki , Nagata Atsushi , Kubonaka Nobuo , Fujiwara Yuji
Published: November 2013

Carbon nanotubes (CNTs) filled with iron nanowires show high coercivity owing to their shape anisotropy originating from the high-aspect-ratio shapes of the iron nanowires. In this study, CNTs filled with iron were prepared by the thermal chemical vapor deposition (T-CVD) method using ferrocene as a precursor, and the magnetic properties of the synthesized CNTs were examined in detail. It was found that the CVD temperature and the amount of the ferrocene introduced into the CVD reactor influence the amount of CNT growth and the magnetic properties. The high coercivity of approximately 1.6 kOe or higher was obtained under certain CVD conditions. The selected-area electron diffraction analysis showed that the magnetic properties of the CNTs filled with iron are determined by the crystal structure (α-Fe or Fe3C) of the iron nanowires, which can be controlled by the amount of the ferrocene supplied during CVD.
Effects of Fluorination on Surface Charge Accumulation and Decay of Polyimide Film
Authors: Du Boxue , Li Jie , Du Heng
Published: November 2013

In this paper, we present a study aimed at clarifying the effects of fluorination time on surface charge accumulation and decay behaviors of fluorinated polyimide films. The samples were surface-fluorinated in a laboratory vessel at about 328 K using a F2/N2mixture with 20% F2by volume at 0.05 MPa for 15, 30, 45, and 60 min. Corona charging tests were performed at room temperature with a relative humidity of ∼40%. The chemical composition of the fluorinated layer of the samples was observed. The results indicate that charge density and charge decay rate are markedly affected by fluorination and that the degree of fluorination is affected by treatment duration.
Direct Biexciton Creation with Two-Photon Excitation for Ideal Entangled Photon Pair Emissions in Optically Active Quantum Dots
Authors: Gotoh Hideki , Sanada Haruki , Yamaguchi Hiroshi , Sogawa Tetsuomi
Published: November 2013

A scheme for creating biexcitons without undesirable excitons is demonstrated in GaAs quantum dots (QDs) using an optical pumping method. This scheme utilizes resonant two-photon excitation processes for biexcitons with carefully set excitation conditions. In this scheme, biexcitons are directly created from the ground state while suppressing unnecessary exciton creation. Theoretical analysis confirms that our scheme works in actual QDs. Directly created biexcitons will make ideal entangled photons via cascade photoemission processes in a biexciton–exciton system with the reduction in the number of undesirable single photons from excitons that are not related to the cascade processes.
A Back-Gate Controlled Silicon Nanowire Sensor with Sensitivity Improvement for DNA and pH Detection
Authors: Dai Pengfei , Gao Anran , Lu Na , Li Tie , Wang Yuelin
Published: November 2013

Silicon nanowire field-effect transistors (SiNW-FETs) are emerging as powerful chemical and biological sensors with various attractive features including high sensitivity and direct electrical readout. However, limited systematic studies have appeared on how the working voltage affects their sensitivity. Here we demonstrate that the current change rate of SiNW-FETs can be exponentially enhanced in the subthreshold regime by both analyses of FET's theory model and electrical characteristics. On that basis, the back-gate controlled sensors' detection sensitivity for DNA and pH value appears great improvement when working in the subthreshold regime, which shows that optimization of SiNW-FET operating conditions, can provide significant improvement for the limits of SiNW-FET nanosensors, making it possible for higher-accuracy chemical and biological molecules detection.
Photoluminescence Characteristics of Bi(m+)-Doped Silica Optical Fiber: Structural Model and Theoretical Analysis
Authors: Wen Jianxiang , Wang Tingyun , Pang Fufei , Zeng Xianglong , Chen Zhenyi , Peng Gang-Ding
Published: November 2013

The energy levels associated with structural models of different valence states of Bi ions in Bi-doped silica optical fiber are investigated using the density functional theory of quantum-chemical calculation. The Bi5+, Bi3+, and Bi+local structure models with and without Al ion are analyzed and compared with respect to their fluorescence characteristics. The result reveals that the special fluorescence effect possibly comes from Bi5+and/or Bi3+ions. Bi5+ions may combine with Al ions that activate the luminescence center of Bi5+ions. Furthermore, the distinctive fluorescence bands are efficiently generated by the coupling effect between Bi5+and Al3+ions. The fluorescence of Bi3+ions may come from the Bi3+ions with Al-free ion. Fluorescence of Bi+ions may exist, but its contribution to the fluorescence is nominal.
Hybrid Transparent Conductive Films of Multilayer Graphene and Metal Grid for Organic Photovoltaics
Authors: Kim Sung Man , Walker Bright , Seo Jung Hwa , Kang Seong Jun
Published: November 2013

Organic solar cells (OSCs) were fabricated on hybrid transparent conductive films consisting of multilayer graphene (MLG) and metal grids. MLG was transferred onto Ag grids to form hybrid transparent conductive films. The optical transmittance was found to be 87% at a wavelength of 550 nm, while the sheet resistance was measured to be 28 ±7.9 Ω/square. The device characteristics of OSCs prepared on the hybrid films include an open circuit voltage of 0.58 V, a short circuit current of 8.05 mA/cm2, a fill factor of 51%, and a power conversion efficiency (PCE) of 2.38%. The PCE shows 11% improvement compared with that of OSCs fabricated using MLG films without Ag grids. This improvement can be attributed to the reduced sheet resistance of the hybrid film. These results indicate that hybrid films comprising MLG deposited on Ag grids constitute a promising transparent electrode for improving performance in OSCs.
Charge Behaviors around Oxide Device/Pseudo-Physiological Solution Interface with Molecular Dynamic Simulations
Authors: Maekawa Yuki , Shibuta Yasushi , Sakata Toshiya
Published: November 2013

In this study, we investigated the charge behaviors of ions and water molecules at the oxide device/pseudo-physiological solution interface by use of molecular dynamics (MD) simulations because the detection principle of semiconductor-based biosensors is based on the detection of charge density changes at the oxide sensing surface in physiological environments. In particular, we designed an alpha-quartz (100) surface with some charges corresponding to pH=5.5 so that the ionic behaviors for 500 mM each of Na+ and Cl- around the interface were calculated under the surface condition with charges, considering a real system. As a result of the simulation, we defined the region of Debye length from the calculated potential distribution, in which some parameters such as diffusion coefficient and the vibration of water molecules around the interface differed from those of the bulk solution. The elucidation of the solid/liquid interfacial behaviors by the simulation technique should deepen our understanding of the detection principle of semiconductor-based biosensors and will give guidelines for the design of a bio-interface in the field of biosensing technology, because they cannot be demonstrated experimentally.
Mietrecht: Mietmangel – Wie errechnet sich die Mietminderung?
Authors: Harsch Robert
Published: November 2013

Gemäß § 536 Abs. 1 S. 2 BGB hat der Mieter für die Zeit, während der die Tauglichkeit der Mietsache gemindert ist, nur eine angemessen herabgesetzte Miete zu entrichten. In seinem richtungweisenden Urteil hat der BGH (v. 13.4.2011 - VIII ZR 223/10, MDR 2011, 718 = MietRB 2011, 169) eine Methode zur Berechnung der Mietminderung entwickelt. Der folgende Beitrag erläutert die Berechnungsmethode anhand von Beispielen und zeigt die Konsequenzen bzw. Probleme für die Praxis auf.
GEWERBLICHER RECHTSSCHUTZ: Die Werbung mit Testergebnissen der StiftungWarentest Die neue Logo-Lizenz: Zwang oder Option?
Authors: Selting Ingo , Koska Marco
Published: November 2013

Die Werbung mit positiven Testergebnissen bei vergleichenden öffentlichen Warentests, insbesondere solchen der Stiftung Warentest, ist ein beliebtes und immer noch an Relevanz gewinnendes Marketinginstrument. Insbesondere im Online-Handel hat die Bewerbung mit Testergebnissen der Stiftung Warentest ein hohes Potential, Kunden zum Kauf zu bewegen, selbst wenn diese das getestete Produkt noch nie selbst gesehen oder getestet haben. Seit dem 1.7.2013 hat die Stiftung Warentest ein sog. Logo-Lizenz-System für die Nutzung ihrer eingetragenen Marken in der Werbung eingeführt, nach dem für die werbliche Nutzung ihrer Marken erstmals erhebliche Lizenzgebühren verlangt werden. Der Beitrag beleuchtet die Situation vor und nach Einführung des Logo- Lizenz-Systems und beschäftigt sich anhand markenrechtlicher sowie wettbewerbsrechtlicher Überlegungen auch mit alternativen Lösungsansätzen zu dem Abschluss eines kostenintensiven Lizenzvertrages.
WERKVERTRAGSRECHT: Schwarzarbeit – Aktuelle Entwicklungen zu den Folgen bei mangelhaften Werkleistungen
Authors: Pauly Holger
Published: November 2013

Der folgende Beitrag bespricht im Anschluss an die Ausführungen in der MDR 2008, 1196 ff. die aktuellen Rechtsentwicklungen bei der Schwarzgeldabrede. Das zwischenzeitlich befürwortete Bestehen von Gewährleistungsrechten zu Gunsten des Bestellers gehört aufgrund neuester höchstrichterlicher Rechtsprechung nunmehr der Vergangenheit an (BGH, Urt. v. 1.8.2013 - VII ZR 6/13, MDR 2013, 1216). Darüber hinaus zeichnet sich in der Rechtsprechung der Instanzgerichte (s. OLG Schleswig, Urt. v. 16.8.2013 - 1 U 24/13, MDR 2013, 1400, in diesem Heft) die Tendenz ab, dem Auftragnehmer in Fällen der Schwarzgeldabrede weder Vergütungsnoch Bereicherungsansprüche zuzugestehen.
An automatic scaling technique for obtaining F2 parameters and F1 critical frequency from vertical incidence ionograms
Authors: Jiang Chunhua , Yang Guobin , Zhao Zhengyu , Zhang Yuannong , Zhu Peng , Sun Hengqing
Published: November 2013

Recent advances in computing technologies have renewed interest in the intelligent systems for automatic interpretation of ionograms, images obtained by remote sensing of the ionospheric plasma. The ionogram “autoscaling” techniques based on the template matching method, previously rendered unrealistic for their computing complexity, have now become feasible. This work presents an automatic scaling technique for extracting the main features of the F1 and F2 layers of the ionosphere, such as critical frequency and virtual height, from vertical incidence ionograms that do not distinguish O/X polarization of the echoes. The proposed technique uses the quasi‐parabolic segments (QPS) to model the electron density profile shapes that are used to synthesize a pool of candidate traces. Moreover, the empirical orthogonal functions and image technique are applied to reduce the size of the candidate traces so that the auto‐scaling algorithm can run in realistic time. With the template matching algorithm, the technique will provide the initial parameters of the QPS model for the F1 and F2 layers, which are then fine‐tuned to obtain the better fitting parameters. In order to evaluate the performance of this technique, a large data set of ionograms recorded in Wuhan at daytime and nighttime in winter, summer, and equinoctial months, are analyzed and investigated. The automatic scaling results are compared with manually scaling results. Our results indicate that the proposed technique described in this paper is reliable and efficient and will facilitate the statistical study of temporal and spatial ionospheric characteristics over Wuhan.
A dual filtering scheme for nonlinear active noise control
Authors: Delvecchio D. , Piroddi L.
Published: November 2013

Active noise control problems are often affected by nonlinear effects such as distortion and saturation of measurement and actuation devices, which call for suitable nonlinear models and algorithms. The active noise control problem can be interpreted as an indirect model identification problem, due to the secondary path dynamics that follow the control filter block. This complicates the weight update mechanism in the nonlinear case, in that the error gradient depends on the secondary path gradient through nonlinear recursions. A simpler and computationally less demanding approach is here proposed that employs the updating scheme of the standard filtered‐x least mean squares (LMS) or filtered‐u LMS algorithm. As in those schemes, the calculation of the error gradient requires a signal filtering through an auxiliary system, here obtained through a secondary adaptation loop. The resulting dual filtering LMS algorithm performs the adaptation of the controller parameters in a direct identification mode and can therefore be easily coupled with adaptive model structure selection schemes to provide online tuning of the model structure, for improved model robustness. Copyright © 2013 John Wiley & Sons, Ltd.
Metal‐ and Oxidant‐Free Direct sp3 CH Arylation of Pyrrolidine
Authors: Haldar Surajit , Mahato Sujit , Jana Chandan K.
Published: November 2013

Arylated aliphatic N‐heterocycles, and particularly arylated pyrrolidines, have a wide range of applications in medicine as well as in chemistry. Arylation of pyrrolidines mainly relies on metal‐mediated couplings, which produce unwanted toxic metal waste. In this Communication, we report an oxidant‐ and metal‐free method for direct sp3 CH arylation of pyrrolidine employing a highly atom economic three‐component reaction. The method, operating under very simple and mild conditions, is highly selective and very efficient in producing single regioisomer of the arylated product even on a multigram scale. As an alternative to the metal‐mediated reaction, this method has the potential to be used in production at an industrial scale. Moreover, a new approach for CH arylation based on a novel reactivity that differs from the reactivity in Mannich or Betti reactions of iminium ion is presented.
Graphene‐Supported Ultrafine Metal Nanoparticles Encapsulated by Mesoporous Silica: Robust Catalysts for Oxidation and Reduction Reactions
Authors: Shang Lu , Bian Tong , Zhang Baihui , Zhang Donghui , Wu Li‐Zhu , Tung Chen‐Ho , Yin Yadong , Zhang Tierui
Published: November 2013

Graphene nanosheet‐supported ultrafine metal nanoparticles encapsulated by thin mesoporous SiO2 layers were prepared and used as robust catalysts with high catalytic activity and excellent high‐temperature stability. The catalysts can be recycled and reused in many gas‐ and solution‐phase reactions, and their high catalytic activity can be fully recovered by high‐temperature regeneration, should they be deactivated by feedstock poisoning. In addition to the large surface area provided by the graphene support, the enhanced catalytic performance is also attributed to the mesoporous SiO2 layers, which not only stabilize the ultrafine metal nanoparticles, but also prevent the aggregation of the graphene nanosheets. The synthetic strategy can be extended to other metals, such as Pd and Ru, for preparing robust catalysts for various reactions.
Palladium‐Catalyzed ortho‐Selective CH Deuteration of Arenes: Evidence for Superior Reactivity of Weakly Coordinated Palladacycles
Authors: Ma Sandy , Villa Giorgio , Thuy‐Boun Peter S. , Homs Anna , Yu Jin‐Quan
Published: November 2013

We disclose a protocol for the palladium‐catalyzed ortho‐selective CH deuteration of arenes. Phenylacetic acids and benzoic acids are suitable substrates for this reaction. This reaction offers a catalytic route to ortho‐deuterated phenylacetic acids and benzoic acids and demonstrates the sharp difference in reactivity of palladacycle intermediates held together by weak and strong coordination.
Continuous‐Flow Oxidative Cyanation of Primary and Secondary Amines Using Singlet Oxygen
Authors: Ushakov Dmitry B. , Gilmore Kerry , Kopetzki Daniel , McQuade D. Tyler , Seeberger Peter H.
Published: November 2013

Primary and secondary amines can be rapidly and quantitatively oxidized to the corresponding imines by singlet oxygen. This reactive form of oxygen was produced using a variable‐temperature continuous‐flow LED‐photoreactor with a catalytic amount of tetraphenylporphyrin as the sensitizer. α‐Aminonitriles were obtained in good to excellent yields when trimethylsilyl cyanide served as an in situ imine trap. At 25°C, primary amines were found to undergo oxidative coupling prior to cyanide addition and yielded secondary α‐aminonitriles. Primary α‐aminonitriles were synthesized from the corresponding primary amines for the first time, by an oxidative Strecker reaction at –50 °C. This atom‐economic and protecting‐group‐free pathway provides a route to racemic amino acids, which was exemplified by the synthesis of tert‐leucine hydrochloride from neopentylamine.
Probing the Intracellular Glutathione Redox Potential by In‐Cell NMR Spectroscopy
Authors: Rhieu Steve Y. , Urbas Aaron A. , Bearden Daniel W. , Marino John P. , Lippa Katrice A. , Reipa Vytas
Published: November 2013

Non‐invasive and real‐time analysis of cellular redox processes has been greatly hampered by lack of suitable measurement techniques. Here we describe an in‐cell nuclear magnetic resonance (NMR) based method for measuring the intracellular glutathione redox potential by direct and quantitative measurement of isotopically labeled glutathione introduced exogenously into living yeast. By using this approach, perturbations in the cellular glutathione redox homeostasis were also monitored as yeast cells were subjected to oxidative stress.
Total Synthesis of (±)‐Gephyrotoxin by Amide‐Selective Reductive Nucleophilic Addition
Authors: Shirokane Kenji , Wada Takamasa , Yoritate Makoto , Minamikawa Ryo , Takayama Nobuaki , Sato Takaaki , Chida Noritaka
Published: November 2013

A chemoselective approach for the total synthesis of (±)‐gephyrotoxin has been developed. The key to success was the utilization of N‐methoxyamides, which enabled the direct coupling of the amide with an aldehyde and selective reductive nucleophilic addition to the amide in the presence of a variety of sensitive and electrophilic functional groups, such as a methyl ester. This chemoselective approach minimized the use of protecting‐group manipulations and redox reactions, which resulted in the most concise and efficient total synthesis of (±)‐gephyrotoxin described to date.
Synthesis and application of polyacrylate nanocapsules loaded with lilial
Authors: Jing Hu , Weijun Deng , Liqin Liu , Zuobing Xiao
Published: November 2013

Polyacrylate nanocapsules loaded with lilial (PNLs) were prepared via miniemulsion polymerization. Then, the PNLs were applied directly to leather. The influence of the contents of the surfactant and lilial and the stirring speed on the mean size and fragrance loading capacity of the PNLs was investigated in detail. The microstructure of the PNLs was determined by dynamic light scattering (DLS), transmission electron nicroscopy (TEM), Fourier transform infrared (FTIR) spectrometry, and thermogravimetric analysis (TGA). The sustained release properties of the leather finished by PNLs were characterized by scanning electron microscopy (SEM) and gas chromatography with a flame ionization detector (GC‐FID). DLS showed that the mean size of the PNLs was 67.78 nm, and the polydispersity index was 0.076. TEM illustrated that the size of the spherical PNL varied in the range 30–80 nm. FTIR spectroscopy showed that lilial was encapsulated into the polyacrylate nanocapsules. TGA illustrated that the fragrance loading ratio of the nanocapsules reached 36.83%. SEM and GC‐FID indicated that the leather finished by the PNLs had better flexing endurance than that finished by lilial emulsion. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40182.