Bidentate N,O-prolinate ruthenium benzylidene catalyst highly active in RCM of disubstituted dienes

The synthesis of a bidentate N,O-prolinate ruthenium benzylidene from commercially available starting materials and its activity in ring-closing metathesis of functionalized disubstituted dienes at 30 °C is disclosed

Effect of inlet valve timing and water blending on bioethanol HCCI combustion using forced induction and residual gas trapping

This is the post-print version of the final paper published in Fuel. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2007 Elsevier B.V.It has been shown previously that applying forced induction to homogeneous charge compression ignition (HCCI) combustion of bioethanol with residual gas trapping, results in a greatly extended engine load range compared to normal aspiration operation. However, at very high boost pressures, very high cylinder pressure rise rates develop. The approach documented here explores two ways that might have an effect on combustion in order to lower the maximum pressure rise rates and further improve the emissions of oxides of nitrogen (NOx); inlet valve timing and water blending. It was found that there is an optimal inlet valve timing. When the timing was significantly advanced or retarded away from the optimal, the combustion phasing could be retarded for a given lambda (excess air ratio). However, this would result in higher loads and lower lambdas for a given boost pressure, with possibly higher NOx emissions. Increasing the water content in ethanol gave similar results as the non-optimal inlet valve timing

Kolmogorovʼ entropy to investigate variation of forest soil properties in the Czech Republic

A measure of variation in values of physico-chemical properties of different soil groups is influenced by deterministic uncertainty. In this study, we assessed variation level of soil horizon properties in the most wide-spread forest soil groups on territory of the Czech Republic in the period 1953-2010. The assessment of variation was based on the selection of potentially correlating grain-size and chemical properties and a regression analysis (p < 0.05) between normal values (1981-2010) and Kolmogorov (K-) entropy of the forest soil quantities. Cambisols (73%), Stagnosols (10%) and Leptosols (4%) were the most frequently sampled soil groups in the database of 15,287 pits from the state pilot forest surveys during the normal period. The K-entropies of clay, Ntot, CaO and MgO indicated the mean contents in the soil groups more significantly than the entropies of loam, pH and Al2O3. The low variable clay content differentiated the series of Cambisols-Podzols (CM-PZ) from other soil groups. On the contrary, the higher stable clay content differentiated the Luvisols-Retisols-Stagnosols (LV-RT-ST) series. The low stable clay content and the higher Ntot and CaO contents were characteristic of Fluvisols and Gleysols. The CM-PZ series varied from LV-RT-ST by more variable contents of finer grain particles, Ntot and CaO. Relationships between soil properties means and K-entropies suggest different development series.O

The effects of hibernation on the time of coagulation of the American bullfrog, Rana catesbeiana

Cold conditions during winter months greatly reduce heart rate in ectothermic animals, such as bullfrogs, resulting in slow, intermittent blood flow. Slow or intermittent flow of blood often results in coagulation, yet the blood of these ectotherms fails to coagulate. In this study, the effects of the stages of hibernation from the onset of temperature decline, through the duration of constant low temperature exposure, was studied by observing the time of blood coagulation of American bullfrogs (Rana catesbeiana) using activated partial thromboplastin time (aPTT). It was found that the time of coagulation increased incrementally along with the decreasing temperature of the hibernation environment. These results suggest that there is a trend between a decrease in temperature and time of coagulation

When maize is not the first choice: advances in paleodietary studies in the Archaeological Site Río Doncellas (Jujuy, Argentina)

In this work we present new values of stable isotopes of carbon (δ13Cco and δ13Cap) and nitrogen (δ15N) measured in a sample of 13 human individuals found in the Río Doncellas Archaeological Site (Late Period or Regional Developments, ca. 1000 AD-1450 AD) located in the Puna of Jujuy, Northwest of Argentina. The skeletal series belong to the collection of Museo E. Casanova, FFyL - UBA and the Instituto Nacional de Antropología y Pensamiento Latinoamericano, being the result of investigations carried out during the decades of 1940 and 1970, respectively. In addition, in this work we present isotopic compositions of food resources (vegetal and fauna) found in the archaeological record as well as gathered in modern farms located in the study area (Abra Pampa, Cochinoca, Jujuy). This information was used for paleodietary inference, allowing us to establish a hierarchy of the resources that were consumed. The results indicate that maize (Zea mays) is less important than other vegetal resources in the diet, which contradicts the expectations generated from the macrobotanical evidence of the site and the cultivated terraces that surround it. On the other hand, camelids seemed to be widely exploited, which is coherent with the current importance of meat production within the region. These results allow us to assert that the growth of cereals did not have a progressive relevance over other resources.Fil: Killian Galván, Violeta Anahí. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geocronología y Geología Isotopica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geocronología y Geología Isotópica; ArgentinaFil: Samec, Celeste Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geocronología y Geología Isotopica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geocronología y Geología Isotópica; ArgentinaFil: Panarello, Hector Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geocronología y Geología Isotopica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geocronología y Geología Isotópica; Argentin

Gregor Krek. Z bibliografijo po njegovih stopinjah

Bibliografija del in prispevkov Gregorja Kreka obsega njegovo pesniška dela, publicistične spise, strokovna in znanstvena besedila in monografije. Prav tako pa so vanjo uvrščeni tudi spisi in besedila o Gregorju Kreku, pesniku in znanstveniku. *** The bibliography of Gregor Krek’s work comprises his poems, popular articles, scientific treatises, and monographs. It also contains articles about Krek himself as a poet and a scholar

Ecología isotópica en la Puna Seca Argentina: un marco de referencia para el estudio de las estrategias de pastoreo en el pasado

El objetivo de este trabajo consiste en comprender las causas de variación en las composiciones isotópicas de pasturas y camélidos domesticados de la Puna Seca Argentina, a fin de construir un marco de referencia para la interpretación de las composiciones isotópicas de materiales provenientes de contextos arqueológicos del área. Se presentan 26 pares de valores de d13C y d15N medidos sobre dos rebaños de llamas manejados por pastores contemporáneos que emplean técnicas tradicionales de pastoreo. Al mismo tiempo, y para otorgar sentido a los datos medidos sobre dichos rebaños, se midieron 93 pares de valores de d13C y d15N sobre las pasturas consumidas por estas llamas en tres unidades vegetales diferentes situadas en distintas cotas altitudinales dentro del área de estudio. Los resultados presentados aquí demuestran la existencia de diferencias en las composiciones isotópicas de las distintas comunidades vegetales, determinadas por la altitud y la humedad disponible en el ambiente. Por un lado, los valores de d13C medidos sobre la vegetación confirman la presencia de plantas C4 por debajo de la cota altitudinal de 3900 msnm, en oposición a la ausencia de este tipo de plantas por encima de dicha cota. Por otro lado, los valores de d15N medidos sobre la vegetación también se estructuran en función de la altitud, dado que los más elevados se encuentran por debajo de los 3900 msnm mientras que los más bajos se encuentran por encima de dicha cota. Este contraste en los valores isotópicos de la vegetación entre ambas cotas altitudinales determina la existencia de diferencias en los valores de d13C y d15N de los dos rebaños de llamas muestreados. Entonces, en este trabajo se discuten las dimensiones de variabilidad isotópica de la actividad pastoril contemporánea en la Puna Seca Argentina a partir de los valores de d13C y d15N medidos sobre pasturas y llamas. Los resultados presentados aquí pueden plantearse como un marco de referencia para la discusión de las estrategias de pastoreo empleadas por las poblaciones humanas que ocuparon el área desde hace 3500 años.Fil: Samec, Celeste Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geocronología y Geología Isotopica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geocronología y Geología Isotopica; Argentin

The Mars Desert Hypothesis and The Mars-RATE Connection

We present a catastrophic as well as creation scenario that is painted with a broad stroke to explain much of the present topography of the planet Mars. By analogy, we propose that Mars is an analog of an extreme desert. This is the Mars Desert Hypothesis. I propose that there is a history of volcanic eruptions producing rain, flash floods, and volcanic flows which created a terraformed Mars complete with streams and lakes and possibly shallow oceans. Because of the low gravity of Mars, due to its mass, which is about 10% of the Earths, this ‘wet season’ is followed by evaporation and sublimation of water and other light gasses which largely escape the planet’s surface. I also propose that the accelerated radioisotope decay occurring during the RATE episodes, perhaps during the flood on the Earth and/or creation week, creating hot spot volcanism on Mars which resulted in the terraforming of Mars–The Mars-Rate Connection. These proposals are followed by geological evidence observed on the surface of Mars for each

Is the Moon\u27s Orbit Ringing from an Asteroid Collision Event which Triggered the Flood?

We use ordinary Newtonian orbital mechanics to explore the possibility that near side lunar maria are giant impact basins left over from a catastrophic impact event that caused the present orbital configuration of the moon. We hypothesize that this collision was responsible for triggering the Noahic Flood. The results show that a collision of an asteroid swarm equivalent to a single ~80 km diameter rocky asteroid moving at parabolic velocity was sufficient to cause the present radial orbital oscillations of the moon, assuming that the orbit was originally circular