bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel method of generation of Ca(HCO3)2 and CaCO3 aerosols and first determination of hygroscopic and cloud condensation nuclei activation properties
Authors: Zhao D. F. , Buchholz A. , Mentel Th. F. , Müller K.-P. , Borchardt J. , Kiendler-Scharr A. , Spindler C. , Tillmann R. , Trimborn A. , Zhu T. , Wahner A.
Published: September 2010

Abstract. Atmospheric mineral aerosols contain CaCO3 as a reactive component. A novel method to produce CaCO3 aerosol was developed by spraying Ca(HCO3)2 solution, which was generated from a CaCO3 suspension and CO2. By aerosol mass spectrometry the freshly sprayed and dried aerosol was characterized to consist of pure Ca(HCO3)2 which under annealing in a tube furnace transformed into CaCO3. Transmission Electron Microscopy demonstrated that the particles produced were spherical. The method was able to generate aerosol of sufficient concentration and proper size for the study of physiochemical properties and investigations of heterogeneous reactions of mineral aerosol. The dried Ca(HCO3)2 particles were somewhat more hygroscopic than CaCO3 particles. However, during humidification a restructuring took place and ∼2/3 of the Ca(HCO3)2 was transformed to CaCO3. The mixed Ca(HCO3)2/CaCO3(s) particles were insoluble with a growth factor of 1.03 at 95% (hygroscopicity parameter κ=0.011±0.007) relative humidity. This compares to a corresponding growth factor of 1.01 for CaCO3(s) (κ=0.0016±0.0004). Mass spectrometric composition analysis, restructuring, and insolubility of the mixed particles suggested that solid Ca(HCO3)2(s) was observed. This would be in contrast to the current belief that Ca(HCO3)2(s) is thermodynamically instable. The CCN activity of Ca(HCO3)2(s) aerosol (κ≈0.15) is remarkably higher than that of CaCO3 aerosol (κ=0.0019±0.0007) and less than that of Ca(NO3)2. The noticeable but limited solubility of Ca(HCO3)2 of ≈0.01 mol/l explains limited hygroscopic growth and good CCN activity. Experiments in the Large Jülich Aerosol Chamber indicated that Ca(HCO3)2(s) could exist for several hours under dry atmospheric conditions. However, it was likely buried in a protective layer of CaCO3(s). We conclude that Ca(HCO3)2 may be formed in the atmosphere in cloud droplets of activated mineral dust by reaction of CaCO3 with CO2 and H2O. The presence of Ca(HCO3)2 and as a consequence an enhanced CCN activity may alter the influence of mineral aerosol on global climate.
Atmospheric influence on a laser beam observed on the OICETS – ARTEMIS communication demonstration link
Authors: Löscher A.
Published: September 2010

Abstract. In 2006 bi-directional optical inter-satellite communication experiments were conducted between the Japan Aerospace Exploration Agency (JAXA) Optical Inter-orbit Communications Engineering Test Satellite (OICETS) and the European Space Agency (ESA) multi-purpose telecommunications and technology demonstration satellite (Advanced Relay and Technology MISsion) ARTEMIS. On 5 April 2006, an experiment was successfully carried out by maintaining the inter-satellite link during OICETS's setting behind the Earth limb until the signal was lost. This setup resembles an occultation observation where the influence of Earth's atmosphere is evident in the power fluctuations recorded at ARTEMIS's (and OICETS's) receiver. These fluctuations do not exist or are at a low level at a link path above the atmosphere and steadily increase as OICETS sets behind the horizon until the tracking of the signal is lost. This specific experiment was performed only once since atmospheric science was not the goal of this demonstration. Nevertheless, this kind of data, if available more frequently in future, can help to study atmospheric turbulence and validate models. The data present here were recorded at ARTEMIS.
On the impact of the Bimodal Oscillating System (BiOS) on the biogeochemistry and biology of the Adriatic and Ionian Seas (Eastern Mediterranean)
Authors: Civitarese G. , Gačić M. , Lipizer M. , Borzelli G. L. E.
Published: September 2010

Abstract. Analysis of 20-year time-series of the vertically averaged salinity and nutrient data in the South Adriatic shows that the two parameters are subject to strong decadal variability. In addition, nutrient and salinity variations are out of phase. Nutrients in the Ionian and in the Adriatic vary in parallel except that often the nutrient content in the Adriatic is lower than in the Ionian, a fact that has been attributed to primary producer consumption following the winter convective mixing. Horizontal distribution of the nitracline depth in the Ionian suggests that nutrient content in the Adriatic is a function of the circulation pattern in the Ionian that wells up or wells down the nitracline: cyclonic circulation causes a downwelling of the nitracline along the borders of the Northern Ionian Gyre (NIG) and a decrease in the nutrient content of the water flowing into the Adriatic across the Otranto Strait, and vice versa. The circulation variations are due to the Bimodal Oscillating System, i.e. the feedback mechanism between the Adriatic and Ionian. Inversion of the sense of the NIG results in the advection of Modified Atlantic Water or of the Levantine/Eastern Mediterranean (EMed) waters in the Adriatic. Here, we show that the presence of allochtonous organisms from Atlantic/Western Mediterranean (WMed) and EMed/temperate zone in the Adriatic are concomitant with the anticyclonic and cyclonic circulations, respectively, of the NIG. As a consequence of the NIG inversions, in the Ionian, this highly oligotrophic zone shows annual blooms in its central area only during cyclonic circulation. On the basis of the results presented, a revision of the theory of Adriatic ingressions formulated in the early 1950s is proposed.
Quantifying the impact of groundwater depth on evapotranspiration in a semi-arid grassland region
Authors: Soylu M. E. , Istanbulluoglu E. , Lenters J. D. , Wang T.
Published: September 2010

Abstract. The interactions between shallow groundwater and land surface processes, mediated by capillary rise processes from groundwater, may play an important role in the ecohydrology of riparian zones in both humid and semi-arid ecosystems. Some recent land surface models (LSM) incorporate the contribution of groundwater to land surface processes with varying levels of complexity. In this paper, we examine the sensitivity of evapotranspiration at the land surface to the depth of groundwater using three models with different levels of complexity, two widely used representative soil hydraulic parameter sets, and four soil textures. The selected models are Hydrus-1D, which solves the Richards equation, the Integrated Biosphere Simulator (IBIS), which uses a multi-bucket approach with interactions between buckets, and a single-bucket model coupled with a classic simple capillary rise flux approximation. These models are first corroborated with field observations of soil moisture and groundwater elevation data from a site located in south-central Nebraska, USA. We then examine the sensitivity of the Richards equation to node spacing, as well as the relationship between groundwater depth and the ratio of actual to potential evapotranspiration (ET) for various soil textures and water table depths. The results show that selecting one representative soil parameter set over another may result in up to a 70% difference in actual ET (relative to the potential ET) when the depth to water table is in 0–5 m depending on the soil type. Moreover, solution type of the Richards equation and node spacing have also effect on surface ET up to 50% and 30% respectively depending on the depth-to-groundwater and node spacing. Therefore, further studies are needed to understand the sensitivities of land surface and atmospheric models to the existence of saturated layers, including studies with more field validation in regions with different climates and land cover types.
LA GESTIÓN DE LA INFORMACIÓN Y CONOCIMIENTO: SU USO COMO RECURSO ESTRATÉGICO PARA FORTALECER LA ACTIVIDAD CIENTÍFICA EN LA FACULTAD DE MEDICINA VETERINARIA
Authors: Del Pozo Pedro Pablo , Nápoles N , Riveron R
Published: September 2010

Con el propósito de elaborar una estrategia para la gestión de la información y conocimiento orientada a las necesidades de información de la comunidad universitaria en la Facultad de Medicina Veterinaria que permita incrementar la utilización de los recursos de información y la creación del conocimiento, se realizó un diagnóstico estratégico. Para ello se aplicó una encuesta a estudiantes y profesores, donde se midieron aspectos como: la utilización del correo electrónico, el uso de Internet y el uso de los recursos electrónicos disponibles en la intranet e infoservet. Se identificaron los recursos más utilizados por la comunidad universitaria, así como aquellos más deficientes: (empleo de las bases de datos remotas, los gestores bibliográficos, laboratorios virtuales, así como otras herramientas para el trabajo colaborativo). Se elaboró una estrategia específica con sus respectivas acciones y criterios de medidas para lograr un mejor uso de la información y la creación del conocimiento. Como resultado de la aplicación de la estrategia se elevó por estudiantes y profesores el empleo de los recursos de información científica disponibles en la Intranet de la UNAH, Bases de Datos remotas y la RED del MES. Se amplía el trabajo colaborativo en red por profesores e investigadores, así como se generaliza la utilización de Gestores de Referencias y Plantillas para la creación de artículos, monografías y tesis lo cual ha contribuido a elevar el conocimiento y la producción científica. Palabras Clave: Gestión de la Información y Conocimiento, Diagnóstico y Estrategia universitariaDOI: 10.5377/calera.v10i14.27
TRATAMIENTO SILVICULTURAL, MONITOREO Y REPOBLACIÓN CON IGUANA (Iguana iguana) EN BOSQUE DE GALERÍA DE LA UNIDAD PRODUCTIVA HACIENDA LAS MERCEDES, UNIVERSIDAD NACIONAL AGRARIA
Authors: Tapia Emelina , Reyes Francisco , Vindell Karen , Hernández Belkys
Published: September 2010

El estudio fue realizado en la Unidad Productiva "HaciendaLas Mercedes" patrimonio de la Universidad NacionalAgraria (UNA). El objetivo fue contribuir a la conservacióndel Bosque de Galería mediante la aplicación del tratamientosilvicultural de enriquecimiento y repoblación con la especieIguana iguana. La metodología se desarrolló iniciando con unavisita de reconocimiento a La ribera de la Presa Los Sábalos(sitio de la plantación forestal) y a la ribera Presa Las Mercedes(sitio para la repoblación con iguanas). El experimento dede repoblación forestal inició con el establecimiento de seisparcelas con especies forestales (Pithecellobium saman (jacq)Bent, Swietenia humilis Zucc, Guazuma ulmifolia Lam,Calycophyllum candidissimum (Vahl) DC, Albizzia caribeae(Urb).B&R y Dalbergia retusa Hemsl) en un área de 0.22 ha.Dentro de cada parcela se ubicó una parcela útil (16 individuos)para realizar el levantamiento de datos dasométricos (alturacm, diámetro basal mm y sobrevivencia) y análisis estadístico.Luego se identificaron las especies vegetales presentes enla plantación y se monitoreo (caracterización del sitio) deIguana iguana (Iguana verde) y Ctenosaura similis (Garrobonegro también conocida como iguana rayada), para lo cualse establecieron seis transeptos (156 m, 200 m, 209 m, 212m, 190 m y 198 m) en 4.9 ha con la aplicación del métodode King. Posteriormente se estableció la repoblación con laespecie Iguana iguana; para ello se introdujeron 18 hembras y6 machos. Por último se realizo el procesamiento y análisis dela información obtenida. Los mayores incrementos promediostotales y mensuales en altura y diámetro basal se presentaron enC. candidissimum (Vahl) DC (21.93 cm y 3.655 cm y 0.34 mm y0.057 mm). En la sobrevivencia los valores de excelente (100%)lo obtuvieron las especies C. candidissimum (Vahl) DC y D.retusa Hemsl y entre los buenos resultaron G. ulmifolia (76%)y S. humilis (67%). La sobrevivencia promedio de las especiesforestales establecidas fue de (87 %). 10 especies vegetalesfueron identificadas (Elitraria imbricata, Baltimora recta, Sidaacuta, Lantara camara, Rowolfio tetrafila, Commelina difusa,Priva lappulaceae, Mimosa pudica, Datura stramonium ySolanum americanum). En el primer monitoreo no se encontróIguana iguana solo la Ctenosaura similis (52 individuos),observado en los transeptos 2, 4 y 6 (en sitios con árbolesgrandes y frondosos, distantes de la fuente de agua. Despuésde la repoblación, la especie Iguana iguana (51 individuos) seobservó en los transectos 2, 5 y 6 (en sitios próximos a fuentesde agua, árboles pequeños. Y Ctenosaura similis (48 individuos)se observó en los transectos 2, 3, 4 y 6.Palabras clave: Conservación; plantación forestal; cálculosdasométricos; Ctenosaura similis.DOI: 10.5377/calera.v9i12.3
PRODUCCIÓN DE HIJAS DE ESTOLONES EN DOS VARIEDADES DE FRESA (Fragaria spp) EN EL CASTILLITO, LAS SABANAS, MADRIZ.
Authors: Cisne-Contreras José , Benavides-González Álvaro , Laguna-Miranda Reinaldo
Published: September 2010

La presente investigación fue realizada con el objetivo deevaluar la tasa potencial de propagación de dos cultivares defresa (Fragaria spp), bajo las condiciones agroclimáticas de lacomunidad El Castillito, Municipio Las Sabanas, Departamentode Madriz, Nicaragua. Los cultivares utilizados fueron la Festivaly Britget, los cuales se establecieron en un diseño experimentalde bloques completos al azar. Como material de propagación seutilizaron coronas provenientes de la parcela de un agricultor dela comunidad las que se sembraron a distancias de 80 cm entresurcos con distancias entre plantas de 40 cm y 80 cm. El manejode la plantación se realizó de forma orgánica: las plantas fueronfertilizadas con lombrihumus a base de estiércol de ganado, elcontrol de insectos se hizo con neem, el control de enfermedadescon caldo sulfocálcico y el manejo de las hierbas de formamanual. La respuesta de las variables: Número de hojas, Altura deplanta, Cobertura de planta evaluados en la planta madre tuvieronun comportamiento similar bajo el efecto de las dos distanciasde siembra para las dos variedades. Una respuesta similar seencontró en la variable Número de hojas en hijas de estolón. Sinembargo, las variables Número de estolones y Número de plantashijas por planta madre difirieron estadísticamente tanto al efectode la variedad como a la distancia de siembra entre planta. Ladistancia de siembra entre planta de 80 cm desarrolló en promedio2.2 estolones para una producción de 7.3 hijas, en cambio ladistancia de 40 cm registró el desarrollo de 0.75 estolones con 4.4hijas. En cuanto a la variedad, la Festival presentó una producciónde 7.9 hijas, mayor que la producción de la Britget con 3.8 hijas.Palabras clave: Fragaria; estolón; planta hija; propagación;cultivar; coronas; planta madre; lombrihumus; biofertilizanteDOI: 10.5377/calera.v9i12.6
Instrumental para la valoración ambiental del medio construido de los asentamientos rurales
Authors: Hernández H
Published: September 2010

El instrumental contiene un sistema de indicadores, obtenidos de la base del estudio de conceptos y criterios relevantes, y de la caracterización de los asentamientos rurales, que incluye parámetros para evaluar la calidad ambiental del medio construido de los asentamientos rurales. El instrumental diseñado tiene implícito el enfoque sistémico e integral, en aras de alcanzar la sustentabilidad local y fue validado en cinco asentamientos rurales del municipio de Masaya, Nicaragua. El sistema de indicadores se obtuvo de un conjunto de 40 variables significativas, las cuales se interrelacionaron gráficamente tomando en cuenta la teoría de sistemas, y, mediante el proceso por asociación y significado, se obtuvieron 15 indicadores específicos y seis indicadores generales, con su correspondiente sistema categorial. Los resultados de la validación son visualizados en histogramas y matrices. En conclusión, el instrumental permite medir y valorar la calidad ambiental de los asentamientos, evidenciando las carencias y las potencialidades para mejorar las condiciones de vida de sus habitantes. Induce también a orientar el desarrollo integral del asentamiento, así como su desarrollo dentro del sistema territorial. Palabras claves: calidad ambiental; asentamientos rurales; indicadores; valoración ambiental.DOI: http://dx.doi.org/10.5377/nexo.v22i1.38Nexo: Revista Científica Vol.22, No.01, pp.02-09/Agosto 2009
Diseño y montaje de una planta piloto para la extracción de quitina y proteínas
Authors: Escorcia D , Hernández D , Sánchez M , Benevente M
Published: September 2010

El proyecto se basó en el diseño y montaje de una planta piloto para la extracción química de Quitina y proteínas a partir de desechos de crustáceos (camarón y langostino). Se determinó el contenido de humedad del material y las condiciones experimentales óptimas de volumen y concentración de los reactivos involucrados en el proceso. Además, se realizó un análisis técnico y económico del mismo. Los resultados mostraron que la materia prima tiene un alto contenido de humedad entre 68-80% y que las condiciones experimentales para la obtención de Quitina dependen fuertemente de las características del material. Bajo estas condiciones se obtuvo una recuperación mayor del 98% para el caso de caparazón de camarón y de aproximadamente un 58% en el caso del langostino. Por otro lado, para la extracción de proteínas se encontró que la mayor producción ocurre a pH 4.0 y con soluciones provenientes del proceso de desproteinización, sin trituración previa de la materia prima. El estudio técnico proporcionó información básica sobre los costos e inversión del proceso operativo, datos sobre las instalaciones y los equipos asociados al proceso productivo. El análisis económico mostró que se debe tener una inversión inicial de US $ 10,520.94 para el montaje de la planta piloto y de US $ 4,852.58 para gastos de transporte y operación por seis meses. Palabras claves: caparazón de camarón; langostino; método químico; planta piloto; proteínas, quitina.DOI: http://dx.doi.org/10.5377/nexo.v22i2.42Nexo: Revista Científica Vol. 22, No. 02, pp.45-55/Diciembre 2009
Módulos de entrenamiento para la medición y adquisición de datos (Módulo de visión)
Authors: Mejia I , Gutiérrez J , Moncada V
Published: September 2010

En este artículo se presenta el proyecto de diseño e implementación de una herramienta de laboratorio, que pretende contribuir a solucionar el déficit existente de medios de entrenamiento para los estudiantes de la carrera de Ingeniería Electrónica de la Universidad Nacional de Ingeniería. El proyecto está enmarcado dentro del área de automatización industrial, específicamente en la adquisición y procesamiento de imágenes. El sistema de Visión Artificial implementado tiene capacidad de permitir la realización de diferentes prácticas en el área de adquisición y procesamiento de imágenes. Entre las aplicaciones que este sistema ofrece se destacan: Detección de fallas en la fabricación de diferentes productos tales como: Fusibles, Integrados con encapsulado HSIP, Objetos circulares, etc; Lectura de códigos de barras; Reconocimiento óptico de caracteres; Supervisión óptica de indicadores digitales (LCD) y analógicos. Los componentes de hardware cumplen con los estándares de la norma IEEE 1394 (Sensor y Hardware de Adquisición) y el software de procesamiento se implementó utilizando la plataforma LabVIEW. Dentro de los componentes del hardware, se diseñaron diferentes escenarios que incluyeron la posición de la cámara y la cantidad de iluminación en función del objeto a inspeccionar y que a su vez garantizó la adquisición adecuada de los datos, lo que permitió evaluar y contrastar sus usos y aplicaciones. Por su parte el software, ejemplifica los diferentes métodos y algoritmos de procesamiento de imágenes, recreando aplicaciones comunes en la industria nicaragüense. Para asegurar el aprovechamiento y uso adecuado del sistema se incluyó la documentación necesaria para conocer el sistema, lo cual es necesario para su correcto uso y mantenimiento. Palabras claves: maquinas de visión; procesamiento de imágenes; control de calidad; adquisición de datos.DOI: http://dx.doi.org/10.5377/nexo.v22i2.43Nexo: Revista Científica Vol. 22, No. 02, pp.56-60/Diciembre 2009
Empresas familiares y estudiantes de ingeniería: Un binomio desaprovechado
Authors: Quintana M
Published: September 2010

Entre agosto y septiembre de 2009, fue realizado un estudio estadístico para conocer los tipos de empresas familiares vinculadas a estudiantes de carreras tecnológicas que ofrece la Universidad Nacional de Ingeniería (UNI), asimismo, en este estudio se investigó acerca de las herramientas tecnológicas que utilizan tales empresas en apoyo de sus actividades económicas. Con ese propósito, fue elaborado y aplicado un cuestionario entre los alumnos y alumnas que estudian las carreras de ingeniería en Computación, Electrónica y Eléctrica y que a su vez tuviesen alguna relación con empresas familiares (muestra voluntaria). De los resultados se encontró que el 96% del total de empresas consultadas (26 empresas), que son representativas de los distintos sectores económicos del país, utilizan escasamente o no utilizan, herramientas tecnológicas en sus procesos productivos o administrativos. Este resultado reflejó que en la actualidad existe un desaprovechamiento de las capacidades y habilidades que posee un sector de la población con alta formación tecnológica entre el sector de las pequeñas empresas familiares, lo que se manifiesta en la poca utilización de parte de las mismas de la tecnología como herramienta de apoyo en sus actividades productivas o comerciales. Las recomendaciones propuestas en función de estos resultados, han conducido a elaborar un plan de trabajo dirigido a ofrecer dichos servicios tecnológicos con el objetivo de respaldar la labor de este sector empresarial a fin de elevar sus ventajas competitivas. Palabras claves: empresas familiares; universidad; tecnología; pequeñas empresas.DOI: http://dx.doi.org/10.5377/nexo.v22i2.44Nexo Revista Científica Vol. 22, No. 02, pp.61-65/Diciembre 2009
Metodología de modelación de escenarios de riesgo sísmico en Managua, Nicaragua
Authors: Ugarte A
Published: September 2010

La investigación Metodología de Modelación de Escenarios de Riesgo Sísmico en Managua, Nicaragua fue ejecutada por el proyecto REDUCCION DEL RIESGO SISMICO EN CENTROAMERICA (RESIS II) en su fase II, bajo el auspicio del Centro de Prevención de Desastres en América Central (CEPREDENAC), del cual la Universidad Nacional de Ingeniería (UNI) es parte. Dicha investigación presenta los análisis y resultados de la actualización de la amenaza sísmica, zonificación tectónica y aceleraciones espectrales (PGA) esperadas de Centroamérica y en particular de Managua, Nicaragua. Se presentan formatos de recopilación de información y también algunos ejemplos de los resultados obtenidos de los datos de campo levantados directamente de las edificaciones de viviendas de un barrio de Managua, así como de una extrapolación lograda sobre la base de datos catastrales de la ciudad de Managua. A partir de una muestra de viviendas típicas se establece una clasificación o tipología por cada sistema constructivo a los cuales se les aplico el Método de Análisis Estático No Lineal de Estructuras (PUSHOVER) generándose un análisis de la capacidad de la estructura acorde con una demanda y por ende el punto de desempeño, el cual representa el Máximo Desplazamiento Estructural esperado para un sismo dado y así reflejar el grado de vulnerabilidad. Finalmente, se presenta una guía de usuario del software denominado SELENA (SEismic Losses EstimatioN through a logic tree Aproach) diseñado para aplicarse a esta investigación, con el objetivo de lograr la modelación del riesgo sísmico para Managua. Palabras claves: vulnerabilidad, prevención de desarstres, aceleraciones espectrales, método no lineal.DOI: http://dx.doi.org/10.5377/nexo.v23i1.34Nexo: Revista Científica Vol. 23, No. 01, pp.09-17/Mayo 2010
Una nueva expresión acerca del producto de convolución de la derivada de orden k de la delta de Dirac
Authors: Aguirre M
Published: September 2010

Palabras claves: distribución; convolución; producto; delta de Dirac; teoría de distribucione AMS Subjet Classification, 46F10, 46F12.DOI: http://dx.doi.org/10.5377/nexo.v23i1.37Nexo: Revista Científica Vol. 23, No. 01, pp.33-39Mayo 2010
The Role of Wind Tunnel Experiments inCFDValidation
Authors: Favier Daniel
Published: September 2010

An attempt to answer the question of the current and future role of wind tunnel experiments in CFD validation is derived by using a selection of typical examples of suited experiments in the field of unsteady aerodynamics at subsonic flow regimes. Such examples concern 2D/3D flows over airfoils, cylinders, as well as tapered wings, and illustrate the three‐folded role of experiments. The three folds consist in providing a detailed description of the physics of complex flow phenomena, constituting reliable databases, and establishing reference comparisons for the CFD validation, both on global and local aerodynamic fields. Some points of interest, for instance integrating the use of wind tunnel experiments and CFD approaches, are also discussed including the evaluation of uncertainties in experimental and numerical results and requirements to yield efficient experimental databases.
Bulk Nanostructured Materials: Non‐Mechanical Synthesis
Authors: Ivanisenko Yulia , Darbandi Azad , Dasgupta Subho , Kruk Robert , Hahn Horst
Published: September 2010

An overview of the synthesis and processing techniques for bulk nanostructured materials that are based on “bottom‐up” approaches is presented. Typically, these processes use nanoparticles, which can be produced by a variety of methods in the gas, liquid or solid state, as the basic building blocks. Their assembly into bulk nanostructured materials requires at least one more processing step, such as compaction or the formation of thick films. For certain nanostructures, film deposition techniques can also be employed. A wide range of nanostructures – from thick films with theoretical density to bulk nanocrystalline materials with nanoporosity – exhibiting novel structural and functional properties useful in many fields of applications are presented. Additionally, the properties of these bulk nanostructured materials can be categorized as either tailored, i.e., microstructure‐dependent and inherently irreversible, or tunable, i.e., reversible by the application of an external field. Examples of both categories of properties are presented and the special role of the synthesis and processing routes to achieve the necessary nanostructures is emphasized.
Micro‐and Nanoscale Metallic Glassy Fibers
Authors: Yi Jun , Xia Xing Xiang , Zhao De Qian , Pan Ming Xiang , Bai Hai Yang , Wang Wei Hua
Published: September 2010

When bulk materials are made into micro‐and nanoscale fibers, there will be attractive improvement of structural and functional properties, even unusual experimental phenomena [Ref. 3]. The main drawback of various applications of metallic fibers is poor ability of present fabrication methods for controlling their dimensions and surface properties [Ref. 4,5]. Metallic glassy fibers (MGFs) are desired because of unique mechanical and physical properties and glass‐like thermoplastic processability of metallic glasses (MGs). Here, we report a synthetic route for production of micro‐to nanoscale MGFs (the diameter ranges from 100 µm to 70 nm) by driving bulk metallic glass rods in their supercooled liquid region via superplastic deformation. Compared with existing metallic fibers, the MGFs have precisely designed and controlled properties and size, high structural uniformity and surface smoothness, and extremely flexibility. Remarkably, the method is simple, efficient, and low cost, and the MGFs can be continuous prepared by the method. Furthermore, the MGFs circumvent brittleness of MGs by size reduction. We proposed a parameter based on the thermal and rheological properties of MG‐forming alloys to control the preparation and size of the fibers. The MGFs with superior properties might attract intensive scientific interest and open wide engineering and functional applications of glassy alloys.
Effect of the Ionic Conductivity on the Performance of Polyelectrolyte‐Based Supercapacitors
Authors: Wee Grace , Larsson Oscar , Srinivasan Madhavi , Berggren Magnus , Crispin Xavier , Mhaisalkar Subodh
Published: September 2010

In the emerging technology field of printed electronics, circuits are envisioned to be powered with printed energy sources, such as printed batteries and printed supercapacitors (SCs). For manufacturing and reliability issues, solid electrolytes are preferred instead of liquid electrolytes. Here, a solid‐state, polyanionic proton conducting electrolyte, poly(styrenesulfonic acid) (PSS:H), is demonstrated for the first time as an effective ion conducting electrolyte medium in SCs with electrodes based on carbon nanotube (CNT) networks. The effect of the ionic conductivity in the PSS:H film of those SCs is studied at different levels of relative humidity (RH) with impedance spectroscopy, cyclic voltammetry, and galvanostatic charge‐discharge techniques. High capacitance values (85 F g−1 at 80% RH) are obtained for these SCs due to the extremely high effective electrode area of the CNTs and the enhanced ionic conductivity of the PSS:H film at increasing RH level. The charging dynamics are primarily limited by the ionic conductivity of the electrolyte rather than a poor contact between the electrolyte and the CNT electrodes. The use of polyelectrolytes in SCs provides high mechanical strength and flexibility, while maintaining a high capacitance value, enabling a new generation of printable solid‐state charge storage devices.
Graphene‐based Materials: Graphene and Graphene Oxide: Synthesis, Properties, and Applications (Adv. Mater. 35/2010)
Authors: Zhu Yanwu , Murali Shanthi , Cai Weiwei , Li Xuesong , Suk Ji Won , Potts Jeffrey R. , Ruoff Rodney S.
Published: September 2010

There is intense interest in graphene in fields such as physics, chemistry, and materials science, among others. Interest in graphene's exceptional physical properties, chemical tunability, and potential for applications has generated thousands of publications and an accelerating pace of research, making review of such research timely. Here is an overview of the synthesis, properties, and applications of graphene and related materials (primarily, graphite oxide and its colloidal suspensions and materials made from them), from a materials science perspective.
A Direct Synthesis of Symmetrical (E,E)‐1,4‐Diaryl‐1,3‐butadienes by Wenkert Arylation of Thiophene
Authors: Hintermann Lukas , Schmitz Marco , Chen Yun
Published: September 2010

The nickel‐catalyzed coupling of thiophene with aryl Grignard reagents (Wenkert reaction) is accelerated by N‐heterocyclic carbene or trialkylphosphane ligands, providing a general, scalable direct synthesis of symmetrical 1,4‐diarylbutadienes.
An iteratively refined distillation line method
Authors: Hassan Chris , Lucia Angelo
Published: September 2010

The focus of this article is distillation design feasibility. It is shown that existing methods for determining feasibility can give incorrect results or produce feasible designs that waste energy due to over‐specification and mass balance errors. An iterative refinement procedure based on direct substitution is proposed within the distillation line method of Lucia et al. that automatically adjusts one product composition to determine feasibility. Direct substitution equations are presented in detail and 14 literature examples are used to illustrate the efficacy of iterative refinement. Numerical results show that iterative refinement can find feasible designs that other methods cannot find, often resulting in significant reductions in energy requirements, and that it is all product compositions, not just trace compositions that affect most shortcut methods for distillation design. Iterative refinement can also find minimum energy requirements and identify sets of specifications that give infeasible designs. © 2010 American Institute of Chemical Engineers AIChE J, 2011
Autoimmunity to human thyroglobulin: Respective epitopic specificity patterns of anti‐human thyroglobulin autoantibodies in patients with sjögren's syndrome and patients with hashimoto's thyroiditis
Authors: Bouanani Majida , Bataille Regis , Piechaczyk Martine , Salhi Sharon Lynn , Pau Bernard , Bastide Madeleine
Published: September 2010

We evaluated the epitopic specificity pattern of anti‐human thyroglobulin (anti‐hTg) autoantibodies from patients with primary Sjögren's syndrome (SS). All of the primary SS sera tested contained both IgG and IgM anti‐hTg autoantibodies recognizing at least 1 region on hTg; in 65% of the cases, 3 or more regions were recognized. A strong recognition of region II, as is seen in Hashimoto's thyroiditis, was associated with thyroid disorder in primary SS. These results emphasize the importance of region II in autoimmune thyroid disease.
Projektallianzen für Großbauvorhaben — lediglich “noch ein Partnerschaftsmodell” oder Paradigmenwechsel der Vertragsgestaltung?
Authors: Sundermeier Matthias , Schlenke Christoph
Published: September 2010

Großbauvorhaben bringen im Regelfall beträchtliche wirtschaftliche Risiken mit sich. Bedingt ist dies nicht zuletzt durch Schwächen der Projektorganisation. Traditionelle Formen der Vertragsgestaltung dominieren bis heute die Praxis, obgleich ihre Regelungsmechanismen für ein effizientes Risikomanagement komplexer Bauprojekte strukturell unzureichend sind. Als Konsequenz drohen den Baubeteiligten erhebliche Konflikte bei der Vertragsabwicklung und beträchtliche wirtschaftliche Einbußen aus mangelhafter Risikobewältigung. Einen Weg hin zu einer effizienteren Abwicklung anspruchsvoller Großbauvorhaben zeigt das Konzept der Projektallianzen, die sich im angloamerikanischen Raum und besonders in der Bauwirtschaft Australiens seit geraumer Zeit mit großem Erfolg für die Realisierung komplexer Hochbau‐, Ingenieurbau‐ und Infrastrukturmaßnahmen etabliert haben. Gegenüber traditionellen Vertragstypen bedeutet das Allianzkonzept einen Paradigmenwechsel, weil es den Erfolg aller Parteien einzig an das wirtschaftliche Ergebnis des Gesamtprojekts koppelt und damit für eine Interessengleichrichtung der Projektbeteiligten sorgt.

Alliancing in large‐scale construction projects — only another partnering approach or even a paradigm shift in contracting? Large‐scale construction projects involve regularly considerable economic risks, not least generated by defects in project organisation. Although regulation mechanisms for an efficient risk management of complex construction projects are structurally insufficient traditional contracts are still dominating in practice. As a consequence of poor risk management disputes and significant financial losses are imminent throughout the construction process. An answer to this problem is shown by the concept of alliancing, which offers an opportunity for a more efficient delivery of largescale construction projects and particularly has been established in the construction industry of Australia. In contrast to traditional methods of construction contracting alliancing means a paradigm shift because it aligns the interests of all parties by linking the financial success of all parties to the performance of the entire project.
Maternal periconceptional exposure to cigarette smoking and alcohol consumption and congenital diaphragmatic hernia
Authors: Caspers Kristin M. , Oltean Cristiana , Romitti Paul A. , Sun Lixian , Pober Barbara R. , Rasmussen Sonja A. , Yang Wei , Druschel Charlotte ,   and the National Birth Defects Prevention Study
Published: September 2010

BACKGROUND: Congenital diaphragmatic hernia (CDH) is a major birth defect that occurs when abdominal organs herniate through a diaphragmatic opening into the thoracic cavity and is associated with high mortality (>50%). The etiology of CDH is not well understood. METHODS: Using data from the National Birth Defects Prevention Study, we examined associations between CDH and maternal periconceptional exposure (1 month before through the third month of pregnancy) to cigarette smoking and alcohol. Interview reports of exposures were provided by mothers of CDH (n = 503) and unaffected control (n = 6703) infants delivered from October 1997 through December 2005. Any exposure (yes/no), as well as quantity (average number of cigarettes or drinks), type (active/passive smoking; beer, wine, distilled spirits), and duration (e.g., number of months exposed) were examined. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated for all CDH cases combined, selected subtypes (Bochdalek, Morgagni, not otherwise specified), and phenotypes (infants with/without additional major birth defects). RESULTS: The aOR for any smoking was nonsignificantly elevated for all CDH cases combined. Odds of any smoking was significant for isolated Bochdalek CDH (aOR, 1.9; 95% CI, 1.2–3.0). The aORs associated with all measures of alcohol consumption were near unity for each CDH category examined. Stratification of smoking exposure by alcohol consumption and stratification of alcohol consumption by smoking exposure did not appreciably change the aORs. CONCLUSIONS: These findings identified periconceptional smoking exposure as a potential risk factor for CDH. Future studies need to confirm our findings and explore possible pathways accounting for the teratogenic effect of smoking. Birth Defects Research (Part A), 2010. © 2010 Wiley‐Liss, Inc.
Upconverted photoluminescence in Ho3+ and Yb3+ codoped Gd2O3 nanocrystals with and without Li+ ions
Authors: Jia Yutao , Song Yinglin , Bai Yunfeng , Wang Yuxiao
Published: September 2010

The upconversion photoluminescence of Ho3+ ion sensitized by Yb3+ ion in Ho3+/Yb3+codoped Gd2O3 nanocrystals with and without Li+ is investigated in this paper. Strong fluorescence in the green (534–570 nm) and red (635–674 nm) regions of the spectrum has been observed, arising from the 5F4/5S2 → 5I8 and 5F5 → 5I8 transitions of Ho3+ ion, respectively. Yb3+ ion is considered to be a better sensitizer for catching enough pumping energy and transferring considerable energy to Ho3+ in the Ho3+/Yb3+system. The upconversion intensity emitted by Ho3+ is greatly enhanced when Li+ is added to the Ho3+/Yb3+ codoped Gd2O3 nanocrystals.
Effect of temperature on intense green emitting Na2Ca(PO4)F:Mn2+ phosphor
Authors: Shinde K. N. , Nagpure I. M. , Fulke Abhay B. , Dhoble S. J.
Published: September 2010

An intense green luminescent Na2Ca(PO4)F:Mn2+ phosphor has been prepared at high temperature by reduction treatment in a charcoal environment. The emission band of Mn2+ was obtained at around 522 nm (green) under 259 nm excitation. Enhancement in emission intensity arising from the thermal treatment is reported. The intense emission of the spectrum was assigned to electronic transitions 4T1 → 6A1 of Mn2+ ions. Intense PL emission suggested that temperature employed plays an important role in the present matrix. X‐ray diffraction pattern, photoluminescence and morphology by SEM of the host lattice of phosphors at different temperatures have been reported in this paper. The results obtained show that the present phosphor has potential for application in green emitting phosphors for the lamp industry. Copyright © 2010 John Wiley & Sons, Ltd.
The Flash Photolysis of 1,3,5‐Cycloheptatriene and Some 7‐Substituted Derivatives
Authors: Thrush B. A. , Zwolenik J. J.
Published: September 2010

Flash Photolysis of ditropyl and ditropyl sulphide in excess inert gas yields the transient spectrum of the tropyl radical. This spectrum consists of a Rydberg series in the ordinary U.V. converging to an ionisation limit at 6.237 eV. Under the same conditions, flash photolysis of cycloheptatriene or of 7‐cyanocycloheptatriene yields toluene or toluonitriles respectively. In the former case, the benzyl radical is observed; this is formed from an energy‐rich, quenchable precursor.
Réactions Photochimiques de Quelques Monomères Irradiés A L'État Solide
Authors: Bernas A. , Bodard M. , Rossi I.
Published: September 2010

Les monomères suivants ont été irradiés à l'état solide à — 196°C ou — 100°C, sous différentes longueurs d'onde (1850 à 3660 Å) en présence ou en absence d'eau oxygénée : l'acrylate de méthyle (AM), le méthacrylate de méthyle (MAM), l'acrylonitrile (AN) et le méthacrylonitrile (MAN). En absence d'eau oxygénée aucun de ces quatre monomères ne polymérise; en présence d'eau oxygénée, seul l'AM conduit à un polymère. Dans ces conditions, la propagation procède vraisemblablement par un mécanisme radicalaire. Pour des irradiations X ou γ des mêmes monomères, des signaux RPE analogues sont obtenus; on peut donc admettre un mécanisme semblable.

Dans le cas particulier de l'AN, l'irradiation à — 196°C conduit à un dégagement de cyanogène et à la formation d'un solide brun dont le spectre d'absorption infra‐rouge présente des bandes caractéristiques du groupement CONH2. La réaction d'hydratation qui peut conduire à CONH2 est discutée.

On envisage également les raisons de l'absence d'une réaction de propagation à — 196°C dans le cas des deux nitriles examinés.
A Metastable Intermediate in the Anaerobic Photolysis of Riboflavin
Authors: Holmström Bertil
Published: September 2010

Using flash photolysis and kinetic spectroscopy, a metastable intermediate has been detected in the anaerobic photolysis of riboflavin (D) in neutral aqueous solution. Judging from its reactions and its absorption spectrum, the intermediate appears to be the semiquinone, DH·. The fading can then be written

where AH2 is any reducing agent (for instance the activator or the side chain of the dye itself). Quenchers like KI or O2 affect step (1).

In presence of oxygen measurable amounts of the intermediate are produced only in presence of activators. In this case the intermediate disappears much faster, and by a first order reaction. This is consistent with a competing step (3) DH· + O2 → D + HO2·.

Absolute values can be estimated for the concentration of the intermediate, its absorptivity, and its decay rate. This is found to be slightly lower than the maximum rate allowed by diffusion considerations.

The fading process is known to be fundamentally different in presence and in absence of activators (in the latter case only, degradation of the riboflavin side chain takes place). Nevertheless, the intermediate reported here seems to be almost the same in the two cases.
Identifying persons feigning limitations in their competence to proceed in the legal process
Authors: Guenther Christina C. , Otto Randy K.
Published: September 2010

Accurate assessment of the response styles criminal defendants adopt when undergoing evaluations of their competence to proceed with the legal process is critical because some feign limitations in their abilities in an attempt to delay or avoid prosecution. This study examined the utility of the Inventory of Legal Knowledge (ILK) to identify persons motivated to feign competence related limitations. That the ILK has good potential as a screening tool is indicated by findings that the measure (1) has adequate test–retest reliability and (2) classified correctly the large majority of participants in two samples (i.e., college students and psychiatric patients) who completed the measure under “honest” or “fake bad” conditions. Copyright © 2010 John Wiley & Sons, Ltd.
ChemInform Abstract: Short Range Structure of B2O3‐Cs2O Glasses Analyzed by X‐Ray Diffraction and Raman Spectroscopy.
Authors: IWADATE Y. , IGARASHI K. , HATTORI T. , NISHIYAMA S. , FUKUSHIMA K. , MOCHINAGA J. , IGAWA N. , OHNO H.
Published: September 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Crystal Structure of the Compound Ho4Ir13Ge9.
Authors: SOLOGUB O. L. , PROTS YU. M. , SALAMAKHA P. S. , PECHARSKY V. K. , BODAK O. I.
Published: September 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Time‐of‐Flight Investigation of IR Laser‐Induced Multilayer Desorption of Benzene.
Authors: BRAUN R. , HESS P.
Published: September 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Rotational Spectrum of 2,2‐Dimethylthiirane.
Authors: HARTWIG H. , DREIZLER H.
Published: September 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Decomposition Kinetics of the N‐Bromoaminoacids, N‐Bromoalanine, N‐ Bromo‐2‐aminobutyric Acid, and N‐Bromonorvaline
Authors: ANTELO J. M. , ARCE F. , CRUGEIRAS J. , ARMESTO J. L.
Published: September 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Efficient Catalytic Addition of Aromatic Carbon‐Hydrogen Bonds to Olefins.
Authors: MURAI S. , KAKIUCHI F. , SEKINE S. , TANAKA Y. , KAMATANI A. , SONODA M. , CHATANI N.
Published: September 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Oxidation of 2,4‐Didehydroadamantane.
Authors: TEAGER D. S. , MURRAY R. K. JUN.
Published: September 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Novel Photoinduced Fenton′s Reaction. Perfluorinated Poly(p‐ Phenylene)‐Catalyzed Photohydroxylation of Benzene with O2 and H2O to Phenol.
Authors: MARUO K. , WADA Y. , YANAGIDA S.
Published: September 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Novel Sulfur‐Containing Agrochemicals: Synthesis of Mercaptotriazoles, Triazolo(3,4‐b)thiadiazole, Triazolo(3,4‐b)thiadiazine and Triazolo(3, 4‐b)thiadiazepine Ring Systems as Possible Fungitoxic Agents.
Authors: HANNA M. A. , KHODEIR M. N. , MASHALY M. A. , EL‐SHAFEI H. M.
Published: September 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.