Literatura académica sobre el tema "N retention"

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros

Elija tipo de fuente:

Consulte las listas temáticas de artículos, libros, tesis, actas de conferencias y otras fuentes académicas sobre el tema "N retention".

Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.

También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.

Artículos de revistas sobre el tema "N retention"

1

Zhang, Gang, Dejian Wang y Yuanchun Yu. "Investigation into the Effects of Straw Retention and Nitrogen Reduction on CH4 and N2O Emissions from Paddy Fields in the Lower Yangtze River Region, China". Sustainability 12, n.º 4 (24 de febrero de 2020): 1683. http://dx.doi.org/10.3390/su12041683.

Texto completo
Resumen
Straw retention is a widely used method in rice planting areas throughout China. However, the combined influences of straw retention and nitrogen (N) fertilizer application on greenhouse gas (GHG) fluxes from paddy fields merits significant attention. In this work, we conducted a field experiment in the lower Yangtze River region of China to study the effects of straw retention modes and N fertilizer rates on rice yield, methane (CH4) and nitrous oxide (N2O) emission fluxes, global warming potential (GWP), and greenhouse gas intensity (GHGI) during the rice season. The experiments included six treatments: the recommended N fertilizer—240 kg N·ha−1 with (1) no straw, (2) wheat straw, (3) rice straw, and (4) both wheat and rice straw retentions; in a yearly rice–wheat cropping system (N1, WN1, RN1, and WRN1, respectively); as well as both wheat and rice straw retentions with (5) no N fertilizer and (6) 300 kg N·ha−1 conventional N fertilizer (WRN0, WRN2). The results showed that CH4 emissions were mainly concentrated in the tillering fertilizer stage and accounted for 54.2%–87.5% of the total emissions during the rice season, and N2O emissions were primarily concentrated in the panicle fertilizer stage and accounted for 46.7%–51.4% total emissions. CH4 was responsible for 87.5%–98.5% of the total CH4 and N2O GWP during the rice season, and was the main GHG contributor in the paddy field. Although straw retention reduced N2O emissions from paddy field, it significantly increased CH4 emissions, which resulted in a significant net increase in the total GWP. Compared with the N1 treatment, the total GWP of WN1, WRN1, and RN1 increased by 3.45, 3.73, and 1.62 times, respectively; and the GHGI increased by 3.00, 2.96, and 1.52 times, respectively, so the rice straw retention mode had the smallest GWP and GHGI. Under double-season’s straw retentions, N fertilizer application increased both CH4 and N2O emissions, and the WRN1 treatment not only maintained high rice yield but also significantly reduced the GWP and GHGI by 16.5% and 30.1% (p < 0.05), respectively, relative to the WRN2 treatment. Results from this study suggest that adopting the “rice straw retention + recommended N fertilizer” mode (RN1) in the rice–wheat rotation system prevalent in the lower Yangtze River region will aid in mitigating the contribution of straw retention to the greenhouse effect.
Los estilos APA, Harvard, Vancouver, ISO, etc.
2

Arnold, Christin, Ramona Schweyen, Arne Boeckler y Jeremias Hey. "Retention Force of Removable Partial Dentures with CAD-CAM-Fabricated Telescopic Crowns". Materials 13, n.º 14 (20 de julio de 2020): 3228. http://dx.doi.org/10.3390/ma13143228.

Texto completo
Resumen
The aim of this study was to compare the retention forces after artificial aging of telescopic crowns fabricated either by a conventional lost-wax technique or by computer-aided design/computer-aided manufacturing (CAD-CAM) technology. Two types of telescopic crowns (0°) were fabricated conventionally using high-noble (group A) and non-precious metal (group B). CAD-CAM fabricated telescopic crowns (0°) were made of non-precious metal (group C). Retention forces were assessed before and after artificial aging and after axial and non-axial loading. Initially [I.] and after artificial aging [IV.], specimens of group C (I. 16.2 N; IV. 13.6 N) exhibited the highest retention forces. The retention forces in groups B (I. 12.5 N; IV. 4.6 N) and A (I. 9.6 N; IV. 2.9 N) were found to be lower than those of group C. The retention force differences between the groups were statistically significant (p < 0.001) at all measurement times [I. vs. IV.]. Different fabricated telescopic crowns with approximately identical designs and materials exhibited different retention forces and different long-term retentive behavior. An optimized CAD-CAM process with individually defined design parameters ensured telescopic crowns with a better fit. These findings might influence prospective clinical decision-making.
Los estilos APA, Harvard, Vancouver, ISO, etc.
3

Wollheim, Wilfred M., Brian A. Pellerin, Charles J. Vörösmarty y Charles S. Hopkinson. "N Retention in Urbanizing Headwater Catchments". Ecosystems 8, n.º 8 (28 de noviembre de 2005): 871–84. http://dx.doi.org/10.1007/s10021-005-0178-3.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
4

Devito, Kevin J. y Peter J. Dillon. "Importance of Runoff and Winter Anoxia to the P and N Dynamics of a Beaver Pond". Canadian Journal of Fisheries and Aquatic Sciences 50, n.º 10 (1 de octubre de 1993): 2222–34. http://dx.doi.org/10.1139/f93-248.

Texto completo
Resumen
Annual retentions of total phosphorus (TP) (−11%) and total nitrogen (TN) (−5%) of a headwater beaver pond in central Ontario were low during 1987–88. Annually, inputs exceeded outputs of total reactive P (71%) and NO3–N (35%), and outputs exceeded inputs of total unreactive P (−33%) and total organic N (−26%), and inputs approximated outputs of NH4–N (−8%). Seasonal trends in P and N retention were inversely correlated with runoff. Monthly retention was weakly positively related to average water temperature and redox potential (ORP). Positive monthly retention coincided with low runoff and high biotic assimilation during the growing season. Winter ice cover was associated with undetectable dissolved oxygen and low ORP and increased levels of P and N, particularly NH4–N. High levels of P and N in the surface water during winter were coupled with increased runoff and potentially low biotic assimilation resulting in a net release of TP and TN. Large flow-through of waterborne inputs and flushing of regenerated P and N occurred during peak snowmelt resulting in low annual retention. Initial accumulation of flooded forest material and input of organic matter by beaver may be very important to P and N dynamics, representing a long-term source of nutrients to the pond water and outflow.
Los estilos APA, Harvard, Vancouver, ISO, etc.
5

Chindarungruangrat, Atitiya, Trinuch Eiampongpaiboon y Bundhit Jirajariyavej. "Effect of Various Retentive Element Materials on Retention of Mandibular Implant-Retained Overdentures". Molecules 27, n.º 12 (19 de junio de 2022): 3925. http://dx.doi.org/10.3390/molecules27123925.

Texto completo
Resumen
This study aimed to examine the retentive characteristics of each retentive element material and the effects from thermocycling using the two implant-retained mandibular overdenture model. Two stud abutments and three retentive element materials; nylon, polyetheretherketone (PEEK) and polyvinylsiloxane (PVS) were used in this study. Four tested groups, with a total of 40 overdentures, were fabricated, including a Locator® abutment with nylon retention insert (NY), Novaloc® abutment with PEEK retention insert (PK), Locator® abutment with PVS retention insert (RL), and Novaloc® abutment with PVS retention insert (RN). The retentive force (N) was measured before thermocycling, and at 2500, 5000, and 10,000 cycles after thermocycling. Significant changes in the percentage of retention loss were found in the NY and PK groups (p < 0.05) at 6 and 12 months for the RL group (p < 0.05) after artificial aging. The RN group exhibited a constant retentive force (p > 0.05). The tendency of the percentage of retention loss significantly increased for PEEK, nylon, and PVS silicone over time. The results of the present study implied that retentive element materials tend to lose their retentive capability as a result of thermal undulation and water dispersion. Nylon and PEEK, comprising strong polar groups in polymer chains, showed a higher rate of retention loss than polyvinylsiloxane.
Los estilos APA, Harvard, Vancouver, ISO, etc.
6

Grimm, Nancy B., Richard W. Sheibley, Chelsea L. Crenshaw, Clifford N. Dahm, W. John Roach y Lydia H. Zeglin. "N retention and transformation in urban streams". Journal of the North American Benthological Society 24, n.º 3 (septiembre de 2005): 626–42. http://dx.doi.org/10.1899/04-027.1.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
7

KYLIN, ESKIL. "Über die N-Retention als blutdrucksteigernder Faktor". Acta Medica Scandinavica 58, n.º 1 (24 de abril de 2009): 342–49. http://dx.doi.org/10.1111/j.0954-6820.1923.tb15246.x.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
8

Hrouzek, Ján, Ján Krupčík y Ivan Skačáni. "Correlation Between GC Retention Data and Relative Molecular Weight of N,N-Bis(2,2,2-trifluoroethyl)dithiocarbamates of Some Divalent Metals". Collection of Czechoslovak Chemical Communications 61, n.º 11 (1996): 1609–14. http://dx.doi.org/10.1135/cccc19961609.

Texto completo
Resumen
The correlation of gas-chromatographic retention data (retention times and linear retention indices) and relative molecular weight was examined for N,N-bis(2,2,2-trifluoroethyl)dithiocarbamate chelates of some divalent metals. Regression analysis of data obtained by capillary GC on a non-polar column heated by applying a dual-ramp temperature programme gave linear dependences possessing reasonable correlation coefficients.
Los estilos APA, Harvard, Vancouver, ISO, etc.
9

Tesař, M., O. Syrovátka, M. Šír, Ľ. Lichner, J. Váchal y M. Krejča. "Storm runoff in the foothill headwater area Senotín". Soil and Water Research 3, No. 3 (31 de octubre de 2008): 168–74. http://dx.doi.org/10.17221/6/2008-swr.

Texto completo
Resumen
The purpose of the pilot project Senot&iacute;n (1993&ndash;2000) was to prove the methods of revitalization of sub-mountain headwater area (0.38 km<sup>2</sup>) in the Novobystřick&aacute; Vysočina Highland (610&ndash;725 m a. s. l.) in the Czech Republic. This area was tile-drained and ploughed in 1985. Seven underground clay shields newly constructed in 1995 stopped the function of the tile drainage. Four balks prevented the surface and subsurface runoff. These adaptations improved water retention capacity of the whole catchment, which is demonstrated using an example of runoff formation in the revitalized area. A typical storm rain (total 15 mm, duration 5.6 h, max. intensity 4 mm/20 min) and the consequent runoff was analysed, including the role of the soil in the runoff retardation and water retention. The runoff started in two hours since the rain beginning. The retention reached 98% of the rain total. The runoff lasted for 85 h. The concave-upward shape of the falling hydrograph limb indicates that the maximum retention capacity of the studied catchment is high.
Los estilos APA, Harvard, Vancouver, ISO, etc.
10

Ritz, Stephanie y Helmut Fischer. "A Mass Balance of Nitrogen in a Large Lowland River (Elbe, Germany)". Water 11, n.º 11 (14 de noviembre de 2019): 2383. http://dx.doi.org/10.3390/w11112383.

Texto completo
Resumen
Nitrogen (N) delivered by rivers causes severe eutrophication in many coastal waters, and its turnover and retention are therefore of major interest. We set up a mass balance along a 582 km river section of a large, N-rich lowland river to quantify N retention along this river segment and to identify the underlying processes. Our assessments are based on four Lagrangian sampling campaigns performed between 2011 and 2013. Water quality data served as a basis for calculations of N retention, while chlorophyll-a and zooplankton counts were used to quantify the respective primary and secondary transformations of dissolved inorganic N into biomass. The mass balance revealed an average N retention of 17 mg N m−2 h−1 for both nitrate N (NO3–N) and total N (TN). Stoichiometric estimates of the assimilative N uptake revealed that, although NO3–N retention was associated with high phytoplankton assimilation, only a maximum of 53% of NO3–N retention could be attributed to net algal assimilation. The high TN retention rates in turn were most probably caused by a combination of seston deposition and denitrification. The studied river segment acts as a TN sink by retaining almost 30% of the TN inputs, which shows that large rivers can contribute considerably to N retention during downstream transport.
Los estilos APA, Harvard, Vancouver, ISO, etc.

Tesis sobre el tema "N retention"

1

Macdonald, Andrew James. "The effects of cover crops soil N transformations and losses from arable land". Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326592.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
2

Thomas, Roger Charles. "Retention of N-15 labelled urea in a radiata pine ecosystem : effect of split applications". Thesis, University of Canterbury. Forestry, 1987. http://hdl.handle.net/10092/7500.

Texto completo
Resumen
The efficiency of fertilizer nitrogen uptake and retention within the ecosystem were studied in a 2-year-old radiate pine stand. This was a third rotation site on coastal sand dunes. Application of 90g N/tree (150 kg N/ha), as either Single, 3-split or 9-split dressings, were applied as urea solution, labelled with 2.69 atom % N-15. A control and three seasonal treatments (30 g N/tree) were also included. The trees were in the centre of 7 m² root isolated plots. The experiment ran for a period of 17 months during which time N-15 uptake was monitored by foliar analysis. Steady levels were reached 6 months after the single application. The indicated that soil processes acted on the N-15 pool to achieve an equilibrium with soil-N. The final distribution of fertilizer nitrogen within the ecosystem was determined by a complete tree harvest (including roots) and soil sampling to 90cm. There was a 25% increase in above ground biomass formed in the year after fertilization with 90 g N/tree. The below ground response was more marked, with an 80% increase in fine (<2 mm) roots. Irrespective of the rate, the season of the splitting of the application, the tree’s uptake of fertilizer nitrogen was the same (mean = 21.3%). However, the retention within the soil varied from 40% with a Single application to 70% for the 9-split application. The total ecosystem retention varied from 60% (Single) to 90% (9-Split) excluding volatilization (<2%) and uptake by surrounding trees (<3%). The retention for the seasonal treatments was similar to the split treatments. The was a positive relationship between tree uptake of fertilizer nitrogen and initial sink size. Other major factors determining the range of tree uptakes (15-32%) were leaching and immobilization. The high soil retention of fertilizer nitrogen at the lower application rate, and for split applications, suggests immobilization is a dominant process. Leaching was most prominent for the Single 90 g N application. The extent of this loss may have precluded further uptake by the tree. Although total retention was increased with split applications, there was no immediate benefit to the tree. Given that this additional nitrogen is a very minor proportion of the total; in the soil, the probability of additional; responses seems unlikely. Split applications did not increase tree uptake of nitrogen. Indeed, in the absence of leaching a single application may be utilised more efficiently.
Los estilos APA, Harvard, Vancouver, ISO, etc.
3

Burian, Cosmin. "Improvement of ms based e-nose performances by incorporation of chromatographic retention time as a new data dimension". Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/8482.

Texto completo
Resumen
Mejora del rendimiento de la nariz electrónica basada en espectrometría de masas mediante la incorporación del tiempo de retención cromatografico como una nueva dimensión de datos

La importancia del sentido de olor en la naturaleza y en la sociedad humana queda latente con el gran interés que se muestra en el análisis del olor y el gusto en la industria alimentaria. Aunque las aéreas mas interesadas son las de la alimentación y bebida, también se ha mostrado la necesitad para esta tecnología en otros campos como en el de la cosmética. Lamentablemente, el uso de los paneles sensoriales humanos o paneles caninos son costosos, propensos al cansancio, subjetivos, poco fiables e inadecuados para cuantificar, mientras que el análisis de laboratorio, a pesar de la precisión, imparcialidad y capacidad cuantitativa, necesita una labor intensa, con personal especializado y requiere de mucho tiempo. Debido a estos inconvenientes el concepto de olfato artificial generó un gran interés en entornos industriales.
El término "nariz electrónica" se asocia con una serie de sensores de gases químicos, con una amplia superposición de selectividad para las mediciones de compuestos volátiles en combinación con los instrumentos informáticos de análisis de datos. La nariz electrónica se utiliza para proporcionar una información comparativa en vez de una cualitativa en un análisis, y porque la interpretación puede ser automatizada, el dispositivo es adecuado para el control de calidad y análisis. A pesar de algunos logros prometedores, los sensores de estado sólido de gas no han cumplido con sus expectativas. La baja sensibilidad y selectividad, la corta vida del sensor, la calibración difícil y los problemas de deriva han demostrado serias limitaciones. En un esfuerzo para mejorar los inconvenientes de los sensores de estado sólido, se han adoptado nuevos enfoques, utilizando diferentes sensores para la nariz electrónica. Sistemas de sensores ópticos, la espectrometría de movilidad iónica y la espectrometría infrarroja son ejemplos de técnicas que han sido probadas.
Las narices electrónicas basadas en la espectrometría de masas (MS) aparecieron por primera vez en 1998 [B. Dittmann, S. y G. Nitz Horner. Adv. Food Sci. 20 (1998), p. 115], y representan un salto importante en la sensibilidad, retando a la nariz electrónica basada en sensores químicos. Este nuevo enfoque del concepto de una nariz electrónica usa sensores virtuales en forma de proporciones m/z. Una huella digital compleja y muy reproducible se obtiene en forma de un espectro de masas, que se procesa mediante algoritmos de reconocimiento de patrones para la clasificación y cuantificación. A pesar de que la nariz electrónica basada en la espectrometría de masas supera a la nariz electrónica clásica de sensores de estado sólido en muchos aspectos, su uso se limita actualmente a la instrumentación de laboratorio de escritorio. La falta de portabilidad no representará necesariamente un problema en el futuro, dado que espectrómetros de masas en miniatura se han fabricado ya en una fase de prototipado.
Un inconveniente más crítico de la nariz electrónica basada en MS consiste en la manera en la que se analizan las muestras. La fragmentación simultánea de mezclas complejas de isómeros pueden producir resultados muy similares a raíz de este enfoque. Una nariz electrónica mejor sería la que combina la sensibilidad y el poder de identificación del detector de masas con la capacidad de separación de la cromatografía de gases. El principal inconveniente de este enfoque es de nuevo el coste y la falta de portabilidad de los equipos. Además de los problemas anteriores con la espectrometría de masas, el análisis de cromatografía de gases requiere mucho tiempo de medida.
Para abordar estas cuestiones, se han reportado miniaturizaciones en cromatografía capilar de gases (GC) que hacen posible el GC-en-un-chip, CG-rápido y CG-flash que hacen uso de columnas cortas, reduciendo el tiempo de análisis a los tiempos de elución como segundos y, en algunos casos, se han comercializado. La miniaturización de la espectrometría de masas y cromatografía de gases tiene un gran potencial para mejorar el rendimiento, la utilidad y la accesibilidad de la nueva generación de narices electrónicas.
Esta tesis se dedica al estudio y a la evaluación del enfoque del GC-MS para la nariz electrónica como un paso anterior al desarrollo de las tecnologías mencionadas anteriormente. El objetivo principal de la tesis es de estudiar si el tiempo de retención de una separación de cromatografía puede mejorar el rendimiento de la nariz electrónica basada en MS, mostrando que la adición de una tercera dimensión trae más información, ayudando a la clasificación de las pruebas. Esto se puede hacer de dos maneras:
· comparando el análisis de datos de dos vías de espectrometría de masas con análisis de datos de dos vías de matrices desplegadas y concatenadas para los datos de tres vías y
· comparando el análisis de datos de dos vías del espectrometría de masas con el análisis de datos de tres vías para el conjunto de datos tridimensionales.
Desde el punto de vista de cromatografía, la meta será la de optimizar el método cromatográfico con el fin de reducir el tiempo de análisis a un mínimo sin dejar de tener resultados aceptables.
Un paso importante en el análisis de datos multivariados de vías múltiples es el preprocesamiento de datos. Debido a este objetivo, el último objetivo será el de determinar qué técnicas de preprocesamiento son las mejores para y el análisis de dos y tres vías de datos.
Con el fin de alcanzar los objetivos propuestos se crearon dos grupos de datos. El primero consiste en las mezclas de nueve isómeros de dimetilfenol y etilfenol. La razón de esta elección fue la similitud de los espectros de masas entre sí. De esta manera la nariz electrónica basada en espectrometría de masas sería retada por el conjunto de datos. También teniendo en cuenta el tiempo de retención de los nueve isómeros solos, las soluciones se hicieron, como si el conjunto de datos demostraría el reto si se usaría sólo el tiempo de retención. Por tanto, este conjunto de datos "artificiales" sostiene nuestras esperanzas en mostrar las mejoras de la utilización de ambas dimensiones, la MS (espectros de masas) y la GC (tiempo de retención).
Veinte clases, representando las soluciones de los nueve isómeros se midieron en diez repeticiones cada una, por tres métodos cromatográficos, dando un total de 600 mediciones. Los métodos cromatográficos fueron diseñados para dar un cromatograma resuelto por completo, un pico coeluido y una situación intermediaria con un cromatograma resuelto parcialmente. Los datos fueron registrados en una matriz de tres dimensiones con las siguientes direcciones: (muestras medidas) x (proporción m/z) x (tiempo de retención). Por "colapsar" los ejes X e Y del tiempo de retención cromatográfica y los fragmentos m/z, respectivamente, se obtuvieron dos matrices que representan los espectros de masa regular y el cromatograma de iones totales, respectivamente. Estos enfoques sueltan la información traída por la tercera dimensión y el despliegue por lo que la matriz original 3D y la concatenación de las TIC y el espectro de masa media se han tenido en consideración como una forma de preservar la información adicional de la tercera dimensión en una matriz de dos dimensiones.
Los datos fueron tratados mediante la alineación de picos, con una media de centrado y la normalización por la altura máxima y el área del pico, los instrumentos de pre-procesamiento que también fueron evaluados por sus logros.
Para el análisis de datos de dos vías fueron utilizados el PCA, PLS-DA y fuzzyARTMAP. La agrupación de PCA y PARAFAC fueron evaluados por la relación intervariedad - intravariedad, mientras que los resultados mediante fuzzy ARTMAP fueron dados como el éxito de la las tasas de clasificación en porcentajes.
Cuando PCA y PARAFAC se utilizaron, como era de esperar, el método de cromatografía resuelto (método 1) dio los mejores resultados globales, donde los algoritmos 2D funcionan mejor, mientras que en un caso más complicado (picos más coeluidos del método 3) pierden eficacia frente a métodos 3D.
En el caso de PLS-DA y n-PLS, aunque los resultados no son tan concluyentes como los resultados del PCA y PARAFAC, tratándose de las diferencias mínimas, el modelo de vías múltiples PLS-DA ofrece un porcentaje de éxito en la predicción de ambos conjuntos de datos. También se recomienda el n-PLS en vez de utilizar datos desplegados y concatenados, ya que construye un modelo más parsimonioso.
Para el análisis fuzzyARTMAP, la estrategia de votación empleada ha demostrado que al usar los espectros de masa media y la información del cromatograma de iones totales juntos se obtienen resultados más consistentes.
En el segundo conjunto de datos se aborda el problema de la adulteración del aceite de oliva extra virgen con aceite de avellana, que debido a las similitudes entre los dos aceites es una de las más difíciles de detectar. Cuatro aceites extra virgen de oliva y dos aceites de avellana se midieron puros y en mezclas de 30%, 10%, 5% y 2% con los mismos objetivos mostrando que la adición de la extra dimensión mejora los resultados. Se han hechos cinco repeticiones para cada preparación, dando un total de 190 muestras: 4 aceites puros de oliva, 2 aceites puros de avellana y 32 adulteraciones de aceite de avellana en aceite de oliva, dando un total de 38 clases. Dos métodos cromatográficos fueron utilizados. El primero estaba dirigido a una completa separación de los componentes del aceite de oliva y empleó una separación con temperatura programable, mientras que el objetivo del segundo método fue un pico coeluido, por lo tanto fue contratada una temperatura constante de separación. Los datos fueron analizados por medio de la PCA, PARAFAC, PLS-DA y PLS-n.
Como en el conjunto "artificial" de datos, el PCA y PARAFAC se analizaron por medio de la capacidad de clusterización, que mostró que los mejores resultados se obtienen con los datos desplegados seguido por los datos 3D tratados con el PARAFAC.
Desde el punto de vista de optimización de la columna, los logros obtenidos por la columna corta está por debajo del enfoque de la columna larga, pero este caso demuestra una vez más que la adición de los incrementos de tercera dimensión mejoran la nariz electrónica basada en MS.
Para el PLS-DA y n-PLS se evaluaron las tasas de éxito comparativamente, tanto para las corridas cromatográficas largas como para las cortas. Mientras que para la columna larga el mejor rendimiento es para los datos del cromatograma de iones totales (TIC), la columna corta muestra mejor rendimiento para los datos concatenados de los espectros de masa media y TIC. Además, la predicción de las tasas de éxito son las mismas para los datos TIC de columna larga como para los datos concatenados de la columna corta. Este caso es muy interesante porque demuestra que el enfoque PLS de la tercera dimensión mejora los resultados y, por otra parte, mediante el uso de la columna corta el tiempo de análisis se acorta considerablemente.
Se esperan ciertos logros de la nariz electrónica. Por el momento, ninguno de esos enfoques se acercó lo suficiente para producir una respuesta positiva en los mercados. Los sensores de estado sólido tienen inconvenientes casi imposibles de superar. La nariz electrónica basada en espectrometría de masas tiene una falta de portabilidad y a veces sus logros son insuficientes, y el aparato del cromatógrafo de gases-espectrómetro de masas sufre problemas de portabilidad igual que espectrómetro de masas y toma mucho tiempo. El desarrollo de potentes algoritmos matemáticos durante los últimos años, junto con los avances en la miniaturización, tanto para MS y GC y mostrar cromatografía rápida cierta esperanza de una nariz electrónica mucho mejor.
A través de este trabajo podemos afirmar que la adición del tiempo de retención cromatográfica como una dimensión extra aporta una ventaja sobre las actuales tecnologías de la nariz electrónica. Mientras que para los cromatogramas totalmente resueltos no se logran mejoras o la ganancia es mínima, sobre todo en la predicción, para una columna corta la información adicional mejora los resultados, en algunos casos, hacerlos tan bien como cuando una larga columna se utiliza. Esto es muy importante ya que las mediciones en un cromatógrafo de gases - espectrometro de masas se pueden optimizar para tramos muy cortos, una característica muy importante para una nariz electrónica. Esto permitiría el diseño de un instrumento de mayor rendimiento, adecuado para el control de calidad en líneas de productos.
Los estilos APA, Harvard, Vancouver, ISO, etc.
4

Coleman, Brady S. "Impact of Biochar Amendment, Hydraulic Retention Time, and Influent Concentration on N and P Removal in Horizontal Flow-Through Bioreactors". Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/81880.

Texto completo
Resumen
The advent of industrial, fertilizer-intensive agriculture during the 20th century has promoted export of anthropogenic nutrients, spurring degradation of ecosystem biodiversity and water quality. Exported nitrogen and phosphorus are recognized drivers of this deterioration, and require management. In the mid-1990s, denitrifying bioreactors (DNBRs), a subsurface, edge-of-field best management practice (BMP) that intercepts and treats agricultural drainage by supporting nitrate-attenuating denitrification with a saturated, carbon-filled substrate, were developed. Since then, their utility has expanded, and recent studies have unearthed biochar's capability to stimulate simultaneous nitrate (NO3--N) and phosphate (PO43--P) removal in DNBRs. This study investigated biochar's potential as an amendment to the traditional woodchip media by conducting nine, five-day trials on twelve laboratory-scale, horizontal flow-through DNBR columns. Three media types were tested: woodchips (W), 90% woodchips and 10% biochar (B10), and 70% woodchips and 30% biochar (B30). Simulated agricultural drainage with four unique concentration combinations of 16.1 and 4.5 mg L-1 NO3--N and 1.9 and 0.6 mg L-1 PO43--P was delivered at hydraulic retention times (HRTs) of 3, 6, and 12 h. Mean NO3--N removal efficiencies ranged from 16.9%-93.7%, and media type was insignificant at low influent NO3--N concentrations, but B30 was the most effective at high influent NO3--N concentrations. Mean PO43--P removal efficiencies ranged from -122.0%-74.9%, with B10 and B30 significantly worse than W at removing PO43--P. These findings corroborate previous work indicating boosted NO3--N removal with biochar, but contradict studies upholding PO43--P-removing capabilities.
Master of Science
Los estilos APA, Harvard, Vancouver, ISO, etc.
5

Osnayo, Santamaría Carla Brígida Alejandra. "Informes para la sustentación de expedientes: N° 183516-2008-00670-0-FC / N° 16723-2008-0-1801-JR-CA-14". Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/655659.

Texto completo
Resumen
El Expediente N° 183516-2008 versa sobre la materia de Restitución Internacional del Menor, esta se configura cuando en un primer momento, se genera un hecho de Sustracción Internacional del Menor, es decir, cuando un menor de edad, hasta los 16 años, es trasladado o retenido ilícitamente por uno de sus padres en un país distinto al de su residencia habitual. En ese sentido, con la finalidad de proteger al menor de edad, en el plano internacional, de los efectos perjudiciales que podría ocasionarle un traslado o una retención ilícita, y de establecer los procedimientos que permitan garantizar su restitución, así como de asegurar la protección del derecho de visita, es que el Perú se hace parte de la Convención de la Haya sobre los Aspectos Civiles de la Sustracción Internacional de Menores del 25 de octubre de 1980, que tiene como objeto asegurar la restitución inmediata de los niños, niñas o adolescentes, trasladados o retenidos ilícitamente en cualquiera de los países contratantes y que los derechos de custodia y de visita vigentes en dichos países sean respetados en los demás Estados contratantes, priorizando el principio rector del Interés Superior del Niño en cada proceso.
The file No. 183516-2008 deals with the matter of International Minor Restitution, this is configured when at first an act of International Child Abduction is generated, and that is when a minor, up to 16 years of age, is unlawfully transferred or detained by one of his parents in a different country than his habitual residence. In this sense, in order to protect the minor, at the international level, from the detrimental effects that an illegal transfer or retention could cause, and to establish the procedures that allow guaranteeing their return, as well as ensuring the protection of the access right, is that Peru becomes a member of the Hague Convention on the 1980 Civil Aspects of International Child Abduction, which aims to ensure the immediate restitution of children or adolescents, transferred or detained illegally in any of the contracting countries, and that the custody and access rights applicable in these countries were respected in all the contracting states, prioritizing the guiding principle of the best interests of the child in each process.
Trabajo de suficiencia profesional
Los estilos APA, Harvard, Vancouver, ISO, etc.
6

Zhu, Jinhui, Jun Yang, Rongrong Miao, Zhaoquan Zhaoquan, Xiaodong Zhuang y Xinliang Feng. "Nitrogen-enriched, ordered mesoporous carbons for potential electrochemical energy storage". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-225706.

Texto completo
Resumen
Nitrogen-doped (N-doped) porous carbons have drawn increasing attention due to their high activity for electrochemical catalysis, and high capacity for lithium-ion (Li-ion) batteries and supercapacitors. So far, the controlled synthesis of N-enriched ordered mesoporous carbons (N-OMCs) for Li-ion batteries is rarely reported due to the lack of a reliable nitrogen-doping protocol that maintains the ordered mesoporous structure. In order to realize this, in this work, ordered mesoporous carbons with controllable N contents were successfully prepared by using melamine, F127 and phenolic resin as the N-source, template and carbon-source respectively via a solvent-free ball-milling method. The as-prepared N-OMCs which showed a high N content up to 31.7 wt% were used as anodes for Li-ion batteries. Remarkably, the N-OMCs with an N content of 24.4 wt% exhibit the highest reversible capacity (506 mA h g−1) even after 300 cycles at 300 mA g−1 and a capacity retention of 103.3%. N-OMCs were also used as electrode materials in supercapacitors and a capacity of 150 F g−1 at 0.2 A g−1 with stable cycling up to 2500 times at 1 A g−1 was achieved. These attractive results encourage the design and synthesis of high heteroatom content ordered porous carbons for applications in the field of energy storage and conversion.
Los estilos APA, Harvard, Vancouver, ISO, etc.
7

Zhu, Jinhui, Jun Yang, Rongrong Miao, Zhaoquan Zhaoquan, Xiaodong Zhuang y Xinliang Feng. "Nitrogen-enriched, ordered mesoporous carbons for potential electrochemical energy storage". Royal Society of Chemistry, 2016. https://tud.qucosa.de/id/qucosa%3A30350.

Texto completo
Resumen
Nitrogen-doped (N-doped) porous carbons have drawn increasing attention due to their high activity for electrochemical catalysis, and high capacity for lithium-ion (Li-ion) batteries and supercapacitors. So far, the controlled synthesis of N-enriched ordered mesoporous carbons (N-OMCs) for Li-ion batteries is rarely reported due to the lack of a reliable nitrogen-doping protocol that maintains the ordered mesoporous structure. In order to realize this, in this work, ordered mesoporous carbons with controllable N contents were successfully prepared by using melamine, F127 and phenolic resin as the N-source, template and carbon-source respectively via a solvent-free ball-milling method. The as-prepared N-OMCs which showed a high N content up to 31.7 wt% were used as anodes for Li-ion batteries. Remarkably, the N-OMCs with an N content of 24.4 wt% exhibit the highest reversible capacity (506 mA h g−1) even after 300 cycles at 300 mA g−1 and a capacity retention of 103.3%. N-OMCs were also used as electrode materials in supercapacitors and a capacity of 150 F g−1 at 0.2 A g−1 with stable cycling up to 2500 times at 1 A g−1 was achieved. These attractive results encourage the design and synthesis of high heteroatom content ordered porous carbons for applications in the field of energy storage and conversion.
Los estilos APA, Harvard, Vancouver, ISO, etc.
8

Keuter, Andreas. "Nitrogen response efficiency, nitrogen retention efficiency, and asymbiotic biological nitrogen fixation of a temperate permanent grassland site under different sward compositions and management practices". Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://hdl.handle.net/11858/00-1735-0000-000D-FCBE-5.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
9

García, García Victoria. "Funcionalidad de los humedales mediterráneos en paisajes agrícolas. Factores responsables de la variabilidad espacial y temporal de la retención de N y P= Mediterranean wetland functionality in agricultural landscapes. Driving factors for spatial and temporal variability in N and P retention". Doctoral thesis, Universidad de Murcia, 2013. http://hdl.handle.net/10803/128672.

Texto completo
Resumen
Tesis por compendio de publicaciones
La contaminación difusa procedente de la agricultura contribuye significativamente al incremento de la concentración de nitrógeno (N) y fósforo (P) en los ecosistemas acuáticos continentales, siendo éste un grave problema en la gestión del agua. En las regiones mediterráneas más áridas, como el sureste ibérico, este problema se ve agravado debido a los escasos caudales de los cursos de agua, que disminuyen su capacidad de dilución de solutos y los hace especialmente sensibles a la eutrofización. Está globalmente reconocido que los humedales reducen el flujo de nutrientes desde los ecosistemas terrestres a los acuáticos, siendo así utilizados en el tratamiento de la contaminación difusa en zonas agrícolas, urbanas e incluso mineras. Sin embargo, la diversidad de procesos implicados en la retención de nutrientes determina que la eficiencia de retención de los humedales pueda variar en función del clima y la hidrología. En este sentido, la funcionalidad de los humedales mediterráneos del sureste ibérico para la retención de nutrientes en paisajes agrícolas es en gran medida desconocida. En este contexto, en la presente tesis se plantean cuatro objetivos generales: 1. Conocer la eficiencia de retención de N y P de los humedales asociados a sistemas de drenaje, así como su variación temporal en un ciclo hidrológico. 2. Conocer si existen diferencias en la retención de N y P entre el compartimento superficial y subsuperficial de estos humedales. 3 Analizar los factores ambientales que afectan a la retención de N y P. 4. Analizar la variabilidad espacial, a lo largo del eje longitudinal de los humedales, de la eficiencia de retención de N y P en ambos compartimentos. En base a estos objetivos, se seleccionaron 2 humedales (Taray y Parra) asociados a sistemas de drenaje de cuencas agrícolas del sureste ibérico. En ambos, se tomaron mensualmente muestras de agua superficial y subsuperficial a lo largo de un ciclo hidrológico y se midió la concentración de las diferentes fracciones de N y P. Además, se midieron distintas variables físico-químicas e hidrológicas. Tras ello, se analizó la variabilidad espacial y temporal de la retención de N y P en ambos compartimentos, y con la aplicación de diversos test estadísticos, se llegó a las siguientes conclusiones generales: 1. Los humedales mostraron altas eficiencias de retención de N en ambos compartimentos y frente a elevadas concentraciones de N. El clima cálido parece constituir una ventaja para la retención de N en los humedales mediterráneos. 2. El NO3- fue la fracción mayoritaria del N y mostró los mayores porcentajes de retención. Su variabilidad temporal fue menor en el c. subsuperficial. 3. Las mayores eficiencias de retención de NO3- se registraron en verano. 4. Las eficiencias de retención de NH4+ y de NOT fueron muy inferiores y más variables en el tiempo que las de NO3-. Ningún factor ambiental de los estudiados explicó su variabilidad temporal. 5. El c. subsuperficial mostró una mayor eficiencia de retención de NO3- que el superficial, pero el escaso caudal subsuperficial de los humedales determinó que la carga de NO3- retirada en este compartimento fuese muy inferior a la del superficial. 6. A escala de humedal, el Taray retuvo P mientras la Parra lo exportó. 7. La eficiencia de retención de N y P en los humedales estudiados no mostró un carácter lineal, es decir, el incremento en la longitud del humedal, no generó un incremento proporcional en la retención de nutrientes. 8. La mayor eficiencia de retención de NT y NO3- (99.9% del NT) se observó en los primeros 100 m de humedal. La retención de NH4+ en el c. superficial fue mayor en el último tramo del humedal, donde las altas concentraciones de NH4+ pudieron estimular su asimilación microbiológica. La retención de NOT, PT y PRS no mostró ningún patrón de variación espacial estadísticamente significativo entre tramos. 9. La protección y/o restauración de los humedales asociados a sistemas de drenaje podría ser una herramienta útil para controlar la contaminación difusa en cuencas agrícolas.
Nonpoint source pollution from agriculture areas contributes significantly to increase nitrogen (N) and phosphorus (P) concentrations in freshwater ecosystems, being this a major problem in water management. In the most arid areas of Mediterranean region, such as the Iberian southeast, this problem is specially accused because the majority of aquatic ecosystems have low discharges that diminish their solute dilution capacity, and this make them especially sensitive to eutrophication It is globally recognised that wetlands reduce the flow of nutrients from terrestrial to aquatic ecosystems, being used in the diffuse pollution treatment in agricultural, urban and even mining zones. However, the diversity of processes involved in nutrient retention determines that retention efficiency in wetlands can vary in function of climatic conditions and hydrological regimes. In this sense, the functionality of Mediterranean wetlands, in the Iberian southeast, for nutrient retention in agricultural landscapes is largely unknown. In this context, in the present thesis four general objectives were established: 1. To know the N and P retention efficiency of wetlands associated to drainage systems, as well as, its temporal variability over a hydrological cycle. 2. To know if exist differences in the N and P retention efficiency between the surface and subsurface compartments of these wetlands. 3. Analyse the environmental factors that affect to N and P retention. 4. Analyse the spatial variability, along the longitudinal axis of wetlands, of the N and P retention efficiency in both compartments. Basing on these objectives, we selected two wetlands associated to drainage systems of agricultural catchments in the Iberian southeast (Taray and Parra). In both wetlands, surface and subsurface water samples were collected once a month during a hydrological period and the concentration of the different N and P forms were analysed. In addition, different physicochemical and hydrological variables were measured. Thus, the spatial and temporal variability for N and P retention efficiency was analysed in both wetlands components and next conclusions were established: 1. The wetlands showed high N removal efficiencies at both surface and subsurface components, even for high inflow N concentrations. The warm temperature in the Mediterranean wetlands can be an advantage for N removal. 2. NO3- was the main N form and showed the highest retention percentages. Its temporal variability was lower in the subsurface component. 3. The highest NO3- retention efficiency was observed in summer. 4. The NH4+ and TON retention efficiencies were much lower and more variable through the study period than the NO3- efficiency. The studied environmental factors did not explain their temporal variability. 5. The subsurface component showed a higher NO3- retention efficiency than the surface component, but the lower subsurface discharge defined that the NO3- load removed at the subsurface was much lower than at the surface. 6. At the wetland scale, P was retained in Taray wetland but it was exported in Parra wetland. 7. The N and P retention efficiency in the study wetlands did not show a linear nature, that is, the increase in the wetland length did not cause a proportional increase in the nutrient retention. 8. The highest TN and NO3- (99.9% of TN) removal within wetlands was observed in the first 100 m. The NH4+ retention efficiency at the wetland surface was higher in the last wetland reach, where the high inflow NH4+ concentrations could stimulate the microbial immobilization. TON, TP and SRP retention efficiencies did not show any consistent spatial pattern. 9. The conservation and/or restoration of wetlands associated to drainage systems could be an appropriate tool for the control of non-point pollution in agricultural catchments.
Los estilos APA, Harvard, Vancouver, ISO, etc.
10

Aubertin, Marie-Liesse. "Biochar-compost mixtures : interactions and impact on carbon sequestration and soil fertility". Electronic Thesis or Diss., Sorbonne université, 2022. http://www.theses.fr/2022SORUS173.

Texto completo
Resumen
Dans le contexte actuel des enjeux environnementaux, des stratégies innovantes d’amendement organique peuvent être utilisées afin d’améliorer les propriétés agronomiques du sol, tout en augmentant la séquestration du carbone (C) dans le sol. La combinaison de biochar hautement stable avec du compost, matériau riche en nutriments et contenant du C labile, pourrait être une de ces stratégies, dans un contexte d’économie circulaire. L’objectif de la thèse était d’étudier l’existence d’interactions entre biochar et compost et le cas échéant, de déterminer les mécanismes responsables de leurs effets sur la dynamique du C et de l’azote, ainsi que sur les plantes, à différentes échelles de temps. Pour ce faire, nous avons réalisé des expériences au laboratoire et au champ et analysé les stabilités thermiques et biologiques. La stabilité thermique du biochar a été affectée par les interactions biochar-compost, survenant dès leur mélange. L’altération artificielle a induit des changements sur la stabilité biologique des deux composants. Dans les conditions au champ, les processus induits par les interactions biochar-compost n’ont pas impacté significativement la dynamique du C des mélanges, contrairement à leurs effets sur la friabilité du biochar et la dynamique de l’azote. En conclusion, les interactions entre biochar et compost peuvent se produire à différentes échelles de temps et affecter significativement les propriétés des matériaux ainsi que leur performance en tant qu’amendement organique
In the context of global challenge, innovative organic amendment strategies could be used to improve soil agronomic properties in addition to increasing carbon (C) sequestration in soil. The combination of highly stable biochar with compost, a nutrient-rich material containing labile C, may be a solution to improve C sequestration while enhancing soil fertility in the context of a circular economy. Aim of the thesis was to examine if there are biochar-compost interactions and if yes, what are the mechanisms determining their effect on C and nitrogen (N) dynamics and plant growth, at different time scales. To this end we used laboratory and field experiments and analyzed for biological and thermal stability. The thermal stability of biochar was affected by biocharcompost interactions, which may already occur during their blending. Artificial weathering influenced the biological stability of both materials. Under field conditions, these processes did not significantly influence the carbon dynamics of the mixture, while biochar friability and N dynamics were affected by biochar-compost interactions. We conclude that biochar and compost interactions may occur at different time scales and affect their material properties and performance as soil amendment
Los estilos APA, Harvard, Vancouver, ISO, etc.

Libros sobre el tema "N retention"

1

The Dynamic Retention Model/a Rand Note/Pbm N-2141-Mil. Rand Corp, 1985.

Buscar texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
2

Still-Rolin, Julie. Direct 'n Succeed: Mistakes Companies Make with Recruiting and Retention and How to Avoid Them. Lulu Press, Inc., 2018.

Buscar texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
3

Still-Rolin, Julie. Direct 'n Succeed: Mistakes Companies Make with Recruiting and Retention and How to Avoid Them. Independently Published, 2019.

Buscar texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
4

Teacher Recruitment and Retention With a Special Focus on Minority Teachers (N E a Professional Library). NEA Professional Library, 1989.

Buscar texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
5

Gilmore, Stephen y Lisa Glennon. Hayes & Williams' Family Law. Oxford University Press, 2018. http://dx.doi.org/10.1093/he/9780198811862.001.0001.

Texto completo
Resumen
Hayes and Williams’ Family Law, now in its sixth edition, provides critical and case-focused discussion of the key legislation and debates affecting adults and children. The volume takes a critical approach to the subject and includes ‘talking points’ and focused ‘discussion questions’ throughout each chapter which highlight areas of debate or controversy. The introductory chapter within this edition provides a discussion of the law’s understanding of ‘family’ and the extent to which this has changed over time, a detailed overview of the meaning of private and family life within Article 8 of the ECHR, and a discussion of the Family Justice Review and subsequent developments. Part 1 of this edition, supplemented by the ‘Latest Developments’ section, outlines the most up-to-date statistics on the incidence of marriage, civil partnerships and divorce, discusses recent case law on the validity of marriage such as Hayatleh v Mofdy [2017] EWCA Civ 70 and K v K (Nullity: Bigamous Marriage) [2016] EWHC 3380 (Fam), and highlights the recent Supreme Court decision (In the Matter of an Application by Denise Brewster for Judicial Review (Northern Ireland) [2017] 1 WLR 519) on the pension rights of unmarried cohabitants. It also considers the litigation concerning the prohibition of opposite-sex civil partnership registration from the judgment of the Court of Appeal in Steinfeld and Keidan v Secretary of State for Education [2017] EWCA Civ 81 to the important decision of the Supreme Court in R (on the application of Steinfeld and Keidan) (Application) v Secretary of State for International Development (in substitution for the Home Secretary and the Education Secretary) [2018] UKSC 32. This edition also provides an in-depth discussion of the recent Supreme Court decision in Owens v Owens [2018] UKSC 41 regarding the grounds for divorce and includes discussion of Thakkar v Thakkar [2016] EWHC 2488 (Fam) on the divorce procedure. Further, this edition also considers the flurry of cases in the area of financial provision on divorce such as Waggott v Waggott [2018] EWCA Civ 722; TAB v FC (Short Marriage: Needs: Stockpiling) [2016] EWHC 3285; FF v KF [2017] EWHC 1903 (Fam); BD v FD (Financial Remedies: Needs) [2016] EWHC 594 (Fam); Juffali v Juffali [2016] EWHC 1684 (Fam); AAZ v BBZ [2016] EWHC 3234 (Fam); Scatliffe v Scatliffe [2016] UKPC 36; WM v HM [2017] EWFC 25; Hart v Hart [2017] EWCA Civ 1306; Sharp v Sharp [2017] EWCA Civ 408; Work v Gray [2017] EWCA Civ 270, and Birch v Birch [2017] UKSC 53. It also considers the recent decision of the Supreme Court in Mills v Mills [2018] UKSC 38 concerning post-divorce maintenance obligations between former partners, and the Privy Council decision in Marr v Collie [2017] UKPC 17 relating to the joint name purchase by a cohabiting couple of investment property.Part 2 focuses on child law, examining the law on parenthood and parental responsibility, including the parental child support obligation. This edition includes discussion of new case law on provision of child maintenance by way of global financial orders (AB v CD (Jurisdiction: Global Maintenance Orders)[2017] EWHC 3164), new case law and legislative/policy developments on section 54 of the Human Fertilisation and Embryology Act 2008 (parental orders transferring legal parenthood in surrogacy arrangements), and new cases on removing and restricting parental responsibility (Re A and B (Children: Restrictions on Parental Responsibility: Radicalisation and Extremism) [2016] EWFC 40 and Re B and C (Change of Names: Parental Responsibility: Evidence) [2017] EWHC 3250 (Fam)). Orders regulating the exercise of parental responsibility are also examined, and this edition updates the discussion with an account of the new Practice Direction 12J (on contact and domestic abuse), and controversial case law addressing the tension between the paramountcy of the child’s welfare and the protected interests of a parent in the context of a transgender father’s application for contact with his children (Re M (Children) [2017] EWCA Civ 2164). Part 2 also examines the issue of international child abduction, including in this edition the Supreme Court’s latest decision, on the issue of repudiatory retention (Re C (Children) [2018] UKSC 8). In the public law, this edition discusses the Supreme Court’s clarification of the nature and scope of local authority accommodation under section 20 of the Children Act 1989 (Williams v London Borough of Hackney [2018] UKSC 37). In the law of adoption, several new cases involving children who have been relinquished by parents for adoption are examined (Re JL & AO (Babies Relinquished for Adoption),[2016] EWHC 440 (Fam) and see also Re M and N (Twins: Relinquished Babies: Parentage) [2017] EWFC 31, Re TJ (Relinquished Baby: Sibling Contact) [2017] EWFC 6, and Re RA (Baby Relinquished for Adoption: Final Hearing)) [2016] EWFC 47).
Los estilos APA, Harvard, Vancouver, ISO, etc.

Capítulos de libros sobre el tema "N retention"

1

Nadelhoffer, K., M. Downs, B. Fry, A. Magill y J. Aber. "Controls on N Retention and Exports in a Forested Watershed". En The Bear Brook Watershed in Maine: A Paired Watershed Experiment, 187–210. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-017-3241-3_9.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
2

Rusinamhodzi, Leonard, James Njeru, John E. Sariah, Rama Ngatoluwa y Phlorentin P. Lagwen. "Tillage effect on agronomic efficiency of nitrogen under rainfed conditions of Tanzania." En Conservation agriculture in Africa: climate smart agricultural development, 246–55. Wallingford: CABI, 2022. http://dx.doi.org/10.1079/9781789245745.0014.

Texto completo
Resumen
Abstract Nitrogen (N) deficiency is a common feature in soils managed by smallholder farmers in Africa. Crop residue retention, in combination with no-till (NT), may be a pathway to improve agronomic use efficiency of applied N for small-scale farmers under the predominant rainfed conditions. This chapter reports on the results of a study carried out over two cropping seasons in the long rains of 2014 and 2015 on two sites: (i) on-farm (Mandela); and (ii) a research station (SARI) in eastern Tanzania. The experiment consisted of two tillage systems, conventional tillage (CT) and Conservation Agriculture (CA), with a minimum of 2.5 t ha-1 crop residue cover maintained in the plots during the experiment. CT consisted of soil inversion through tillage and removal of crop residues. In the on-farm experiment, maize was grown in plots with four rates of N application: 0, 27, 54 and 108 kg N ha-1. In the on-station trial, five rates were used: 0, 20, 40, 60 and 100 kg N ha-1. Maize yield and agronomic efficiency (AE) of N were used to assess and compare the productivity of the tested treatments. The results showed that tillage, soil type and rate of N application influenced crop productivity. In the clay soils, the differences between tillage practices were small. Under CT, AE ranged between 21.6 and 53.9 kg/kg N, and it was 20.4-60.6 kg/kg N under CA. The lowest fertilizer application rate of 27 kg ha-1 often had the largest AE across the soil types and tillage practices. In the on-station trials at SARI, the largest AE of 24.6 kg/kg N was recorded under CA with 40 kg N ha-1. As in the on-farm trials, the highest N application rate on-station did not lead to the largest AE. In the CT, AE ranged between 11.5 and 16.8 kg/kg N compared with a range of 15.1 to 24.6 kg/kg N for the CA treatment. Overall, crop residue retention, in combination with NT, is important to improve soil moisture and use efficiency of applied nutrients. Additionally, the initial soil fertility status is also important in determining the magnitude of short-term crop response to applied nutrients. Innovative pathways are needed to achieve the multiple objectives played by maize crop residues for results reported here to be sustainable. However, efficiency of nutrient use needs to be assessed, together with returns on investments, as small yields may mean high nutrient use efficiency but not necessarily significant increased returns at the farm level.
Los estilos APA, Harvard, Vancouver, ISO, etc.
3

Kozerski, Hans-Peter, Horst Behrendt y Jan Köhler. "The N and P budget of the shallow, flushed lake Müggelsee: retention, external and internal load". En Shallow Lakes ’98, 159–66. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-017-2986-4_17.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
4

Lepistö, Ahti, Kirsti Granlund y Katri Rankinen. "Integrated Nitrogen Modeling in a Boreal Forestry Dominated River Basin: N Fluxes and Retention in Lakes and Peatlands". En Biogeochemical Investigations of Terrestrial, Freshwater, and Wetland Ecosystems across the Globe, 113–23. Dordrecht: Springer Netherlands, 2004. http://dx.doi.org/10.1007/978-94-007-0952-2_9.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
5

Schutze, Marie-Paule, Michael R. Jackson y Per A. Peterson. "A Short N-Terminal Sequence is Responsible for the Retention of Invariant Chain (Ii) in the Endoplasmic Reticulum". En Molecular Mechanisms of Membrane Traffic, 59–60. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-662-02928-2_8.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
6

Singh, V. K., B. S. Dwivedi, S. S. Rathore, R. P. Mishra, T. Satyanarayana y K. Majumdar. "Timing Potassium Applications to Synchronize with Plant Demand". En Improving Potassium Recommendations for Agricultural Crops, 363–84. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-59197-7_13.

Texto completo
Resumen
AbstractPotassium (K) demand by crops is almost as high as that of nitrogen (N) and plays a crucial role in many plant metabolic processes. Insufficient K application results in soil K mining, deficiency symptoms in crops, and decreased crop yields and quality. Crop K demands vary with crop types, growth patterns, nutrient needs at different physiological stages, and productivity. Science-based K application in crops needs to follow 4R Nutrient Stewardship to ensure high yield, improved farm income, and optimum nutrient use efficiency. Studies around the world report widespread K deficiency, ranging from tropical to temperate environments. Long-term experiments indicate significant yield responses to K application and negative K balances where K application is either omitted or applied suboptimally. Limited understanding of K supplementation dynamics from soil non-exchangeable K pools to the exchangeable and solution phases and over-reliance on native K supply to meet crop demand are major reasons for deficit of K supply to crops. Research on optimum timing of K fertilizer application in diverse climate–soil–crop systems is scarce. The common one-time basal K management practice is often not suitable to supply adequate K to the crops during peak demand phases. Besides, changes in crop establishment practices, residue retention, or fertigation require new research in terms of rate, time, or source of K application. The current review assesses the synchrony of K supply from indigenous soil system and from external sources vis-à-vis plant demand under different crops and cropping systems for achieving high yield and nutrient use efficiency.
Los estilos APA, Harvard, Vancouver, ISO, etc.
7

Solomon, Barry D. "Nutrient retention". En Dictionary of Ecological Economics, 385–86. Edward Elgar Publishing, 2023. http://dx.doi.org/10.4337/9781788974912.n.54.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
8

"nutrient retention [n]". En Encyclopedic Dictionary of Landscape and Urban Planning, 634. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-540-76435-9_8667.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
9

"5042 retention [n]". En Encyclopedic Dictionary of Landscape and Urban Planning, 828. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-540-76435-9_11585.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
10

"retention [n], nutrient". En Encyclopedic Dictionary of Landscape and Urban Planning, 828. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-540-76435-9_11586.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.

Actas de conferencias sobre el tema "N retention"

1

Verhulst, Anja, Carl F. Verkoelen, Veerle P. Persy y Marc E. De Broe. "CRYSTAL RETENTION CAPACITY OF HUMAN TUBULAR KIDNEY CELLS". En 3rd International Conference on Osteopontin and SIBLING (Small Integrin-Binding Ligand, N-linked Glycoprotein) Proteins, 2002. TheScientificWorld Ltd, 2002. http://dx.doi.org/10.1100/tsw.2002.330.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
2

GRINBERGA, Linda y Ainis LAGZDINS. "NUTRIENT RETENTION IN SURFACE FLOW CONSTRUCTED WETLAND IN AGRICULTURAL LAND IN LATVIA". En RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.179.

Texto completo
Resumen
The research site consists of a pilot-scale surface flow constructed wetland at the farm Mezaciruli located in Zalenieki County, Jelgava Region, in the middle part of Latvia. The constructed wetland was installed in June 2014 to improve water quality in agricultural catchment and examine nutrient retention at the constructed wetland receiving surface and drainage runoff. The constructed wetland’s surface area of 0.37 ha corresponds to 0.5 % of the total catchment area. During the observation period of 32 months (2014-2017) water quality parameters such as total suspended solids (TSS), nitrate-nitrogen (NO3-N), ammonium-nitrogen (NH4-N), total nitrogen (TN), orthophosphate-phosphorus (PO4-P), and total phosphorus (TP) were monitored twice a month using a grab sample approach. Retention efficiency for monitored water quality parameters was calculated based on their concentrations at the inlet and outlet. The monitoring results obtained during this study showed a reduction within the constructed wetland for all examined parameters. The concentrations of NO3-N, NH4-N and TN were reduced on average by 13 %, 15 % and 16 %, respectively. PO4-P and TP concentrations were reduced on average by 38 % and 36 %, respectively. Total suspended solids were reduced by 31% at the outlet of the constructed wetland. However, in some cases, an increase in nutrient concentrations in water leaving the constructed wetland was observed. Therefore, there is a need for further research to investigate causes of such increase.
Los estilos APA, Harvard, Vancouver, ISO, etc.
3

Park, JM, SH Lee, SJ Lee, SC Park, CD Kang y SJ Nam. "ESOPHAGEAL RETENTION OF RESIDUE FROM N-ACETYLCYSTEINE CAPSULE IN PATIENTS UNDERGOING UPPER GASTROINTESTINAL ENDOSCOPY". En ESGE Days 2019. Georg Thieme Verlag KG, 2019. http://dx.doi.org/10.1055/s-0039-1681756.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
4

Sha, Li y Sun Lijun. "Real-time estimation of traffic retention based on M/G/n/0 queuing model". En 2017 Chinese Automation Congress (CAC). IEEE, 2017. http://dx.doi.org/10.1109/cac.2017.8243971.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
5

Mizutani, T., K. Takeuchi, T. Saraya, M. Kobayashi y T. Hiramoto. "Statistical Analysis of Temperature Dependence of Worst Case SRAM Data Retention Voltage Using Extreme Value Theory". En 2019 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2019. http://dx.doi.org/10.7567/ssdm.2019.n-1-04.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
6

Chen, C. Q., G. B. Ang, Z. X. Xing, Y. N. Hua, Z. Q. Mo, Rao Ramesh y Y. Li. "Non-Visible Defect Analysis of OTP Device". En ISTFA 2011. ASM International, 2011. http://dx.doi.org/10.31399/asm.cp.istfa2011p0198.

Texto completo
Resumen
Abstract Several product lots were found to suffer from data retention failures in OTP (one time program) devices. PFA (physical failure analysis) was performed on these devices, but nothing abnormal was observed. Cross-sectional TEM (transmission electron microscopy) revealed no physical defects or abnormal CDs (critical dimensions). In order to isolate the failed layer or location, electrical analysis was conducted. Several electrical simulation experiments, designed to test the data retention properties of OTP devices, were preformed. Meilke's method [1] was also used to differentiate between mobile ion contamination and charge trap centers. Besides Meilke's method, a new electrical analysis method was used to verify the analysis results. The results of our analysis suggests that SiN charge trap centers are the root cause for the data retention failures, and the ratio of Si/N is the key to charge trap center formation. Auger analysis was used to physically check the Si/N ratio of OTP devices. The results support our hypothesis. Subsequent DOE (Design Of Experiment) experiments also confirm our analysis results. Key Words: OTP, data retention, Non-visible defect, AFP, charge trap center, mobile ion.
Los estilos APA, Harvard, Vancouver, ISO, etc.
7

Zhang, Jianhao, Yifeng Hu, Xiaoqin Zhu, Hua Zou, Li Yuan, Jianzhong Xue, Yongxing Sui, Weihua Wu, Sannian Song y Zhitang Song. "N-doped GeTe phase change material for high-temperature data retention and low-power consumption". En 2016 International Workshop on Information Data Storage and Tenth International Symposium on Optical Storage, editado por Fuxi Gan y Zhitang Song. SPIE, 2016. http://dx.doi.org/10.1117/12.2243757.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
8

Enab, Khaled y Hamid Emami-Meybodi. "Impact of Reservoir Fluid and Injection Gas on Shales Huff-N-Puff Performance in the Presence of Diffusion, Sorption, and Hysteresis". En SPE Annual Technical Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/206194-ms.

Texto completo
Resumen
Abstract We assess the huff-n-puff performance in ultratight reservoirs (shales) by conducting large-scale numerical simulations for a wide range of reservoir fluid types (retrograde condensate, volatile oil, black oil) and different injection gases (CO2, C2H6, C3H8) by considering relative permeability hysteresis, diffusion, and sorption. A dual-porosity naturally fractured numerical compositional model is used that considers molecular diffusion and sorption to represent the flow mechanisms during the injection process. Killough's method, Langmuir's adsorption model, and Sigmund correlation are utilized to incorporate hysteresis, sorption, and diffusion, respectively. To investigate the impact of the fluid type, we consider three fluid types from Eagle Ford shale representing retrograde condensate, volatile oil, and black oil. We conduct a comprehensive evaluation of the impact of diffusion, sorption, and hysteresis on the production performance and retention of each fluid and injection gas. Eagle Ford formation is selected because it is the most actively developed shale, and it contains a wide span of PVT windows from dry gas to black oil. The simulation results show that the huff-n-puff process improves the oil recovery by 4-6% when 10% PV of gas is injected. The huff-n-puff efficiency increases with reducing gas-oil-ratio (GOR) as oil recovery from low (GOR) reservoirs is doubled, while recovery from retrograde condensate increased by 20%. C2H6 provides the highest recovery for the black and volatile oil, and CO2 provides the highest recovery for retrograde condensate fluid type. Diffusion and sorption are essential mechanisms to be considered when modeling gas injection to any fluid type in shales. However, the relative permeability hysteresis effect is not significant. Neglecting diffusion during the huff-n-puff process underestimates the oil recovery and retention capacity. The diffusion effect on the oil density reduction is observed more during the soaking period. The diffusion impact increases with higher GOR reservoirs, while the sorption impact decreases with higher GOR. The retention capacity of the injected gas decreases with higher GOR. The diffusion impact on the retention capacity increases with higher GOR. Hence sorption and diffusion must be considered when modeling the huff-n-puff process in ultratight reservoirs.
Los estilos APA, Harvard, Vancouver, ISO, etc.
9

Weiler, Marina, Perla Moreno Castilla, Hannah Starnes, Edward Melendez, Kevin Stieger, Jeffrey Long y Peter Rapp. "EFFECTS OF REPETITIVE TRANSCRANIAL MAGNETIC STIMULATION IN AGED RATS DEPEND ON PRE-TREATMENT COGNITIVE STATUS: TOWARD INDIVIDUALIZED INTERVENTION FOR SUCCESSFUL COGNITIVE AGING". En XIII Meeting of Researchers on Alzheimer's Disease and Related Disorders. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1980-5764.rpda002.

Texto completo
Resumen
Background: Repetitive Transcranial Magnetic Stimulation (rTMS) has shown initial promise in combating age-related cognitive decline and dementia. The nature and severity of cognitive aging, however, varies markedly between individuals. Objective/Hypothesis: We hypothesized that the distinct constellation of brain changes responsible for individual differences in cognitive aging might influence the response to rTMS. Methods: Cognitive effects of rTMS were evaluated using a rat model of cognitive aging in which aged rats are classified as Aged-Impaired (AI) or -Unimpaired (AU) relative to young (Y) according to their performance in the Morris water maze. Several weeks later, following presentation of a sample odor in an olfactory recognition task, rats received either sham (Y, n = 9; AU, n = 8; AI, n = 9) or intermittent Theta Burst Stimulation (Y, n = 8; AU, n = 8; AI, n = 9). Memory was tested 24 hours later. Results: Recognition memory in the sham and stimulated conditions depended on pre-treatment cognitive status in the aged rats. Y and AU sham rats displayed robust odor recognition, whereas sham-treated AI rats exhibited no retention. In contrast, rTMS treated AI rats showed robust retention, comparable in magnitude to Y, whereas the AU stimulated scored at chance. Conclusion: Our results are consistent with a perspective that the unique neurobiology associated with variability in cognitive aging modulates the response to rTMS. Protocols with documented efficacy in young adults may have unexpected outcomes in aging or neurodegenerative conditions, requiring individualized approaches.
Los estilos APA, Harvard, Vancouver, ISO, etc.
10

Kintl, Antonin, Jakub Elbl, Tereza Hammerschmiedt, Igor Hunady y Martin Brtnicky. "EFFECT OF GROWING INTERMEDIATE CROPS PRONE TO FROST KILL ON THE RETENTION AND INCREASE OF N SUPPLY IN THE SOIL". En 21st SGEM International Multidisciplinary Scientific GeoConference Proceedings 2021. STEF92 Technology, 2021. http://dx.doi.org/10.5593/sgem2021/5.1/s20.020.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.

Informes sobre el tema "N retention"

1

Paasch, R. Project H-797, N Reactor 1312-N Liquid Effluent Retention Facility, reanalysis and documentation of design bases. Office of Scientific and Technical Information (OSTI), enero de 1988. http://dx.doi.org/10.2172/7229548.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
2

Dunne-Moses, Abigail, Marcia Alesan Dawkins, Valerie Futch Ehrlich, Cathleen Clerkin y Chelsea Crittle. REAL: CCL’s Research-Based Leadership Framework for Equity, Diversity, and Inclusion in Action. Center for Creative Leadership, noviembre de 2023. http://dx.doi.org/10.35613/ccl.2023.2056.

Texto completo
Resumen
Organizational cultures that emphasize fairness, connection and human-centeredness inspire more effective collaboration, are more economically efficient, and can manage conflict and crisis effectively.[i] Such cultures are also marked by less burnout and more engagement, retention, and satisfaction.[ii] These cultural values directly relate to promoting equity, diversity, and inclusion (EDI) in the workplace. Despite these well-known values, leaders do not always know how to talk about them or make them tangible and practical. REAL is a research informed framework crafted carefully to do exactly that: help leaders make culture change real to the people on their teams. REAL is a research informed framework crafted carefully to do exactly that: help leaders make culture change real to the people on their teams. REAL provides the necessary foundation to generate effective EDI solutions that capture real effects and challenges people face. The current paper describes the REAL framework, the research underpinning its core tenets, and insights for leaders committed to building more equitable, diverse, and inclusive organizational cultures. The elements of the framework are: Reveal relevant opportunities by exploring your organization as a complex system, identifying strategic actions for change, and being clear that goals may be hard to achieve. Elevate equity as foundational to diversity and inclusion efforts because it provides fair opportunities for all to reach full potential. Activate diversity strategically by embracing stakeholders’ vast reservoir of perspectives and experiences, ultimately enhancing innovation and decision-making. Lead inclusively by nurturing connection, vulnerability, courage and investment in initiatives to build respect a sense of significance for every stakeholder. [i] Alemany, L., & Vermeulen, F. (2023, July 1). Disability as a Source of Competitive Advantage. Harvard Business Review. https://hbr.org/2023/07/disability-as-a-source-of-competitive-advantage [ii] Stein, D., Hobson, N., Jachimowicz, J. M., & Whillans, A. (2021, October 13). How Companies Can Improve Employee Engagement Right Now. Harvard Business Review. https://hbr.org/2021/10/how-companies-can-improve-employee-engagement-right-now Citation Moses-Dunne, A., Dawkins, M. A., Ehrlich, V. F., Clerkin, C., & Crittle, C. (2023). The research foundations for REAL: A framework for leadership action in equity, diversity, & inclusion. Center for Creative Leadership. https://doi.org/10.35613/ccl.2023.2056
Los estilos APA, Harvard, Vancouver, ISO, etc.
Ofrecemos descuentos en todos los planes premium para autores cuyas obras están incluidas en selecciones literarias temáticas. ¡Contáctenos para obtener un código promocional único!

Pasar a la bibliografía