Search results for "Solid"

Fatigue life estimation for 30CrNiMo8 steel under in- and out-of-phase combined bending and torsion with variable amplitudes

1996

Fatigue life successively calculated according to three criteria of multiaxial fatigue for randomly varying loading is compared with fatigue life obtained by Sanetra and Zenner in testing cylindrical specimens of 30CrNiMo8 steel by in- and out-of-phase bending and torsion with variable amplitudes. The position of the plane of fatigue fracture is determined using the variance method. The histories of equivalent stresses are schematically represented by the Monte Carlo method. Fatigue damage was computed using the Palmgren-Miner hypothesis. The most realistic estimates of fatigue life in the scatter band of the results with a factor of 3 are obtained on the basis of the criterion of maximum t…

Sun-induced chlorophyll fluorescence II: Review of passive measurement setups, protocols, and their application at the leaf to canopy level

2019

Imaging and non-imaging spectroscopy employed in the field and from aircraft is frequently used to assess biochemical, structural, and functional plant traits, as well as their dynamics in an environmental matrix. With the increasing availability of high-resolution spectroradiometers, it has become feasible to measure fine spectral features, such as those needed to estimate sun-induced chlorophyll fluorescence (F), which is a signal related to the photosynthetic process of plants. The measurement of F requires highly accurate and precise radiance measurements in combination with very sophisticated measurement protocols. Additionally, because F has a highly dynamic nature (compared with othe…

Procédé de Liquéfaction, Saccharification et Fermentation Simultanée à Très Haute Gravité utilisant de la farine de manioc pour la production de l'ét…

2021

A simultaneous liquefaction, saccharification and fermentation (SLSF) process at very high gravity of cassava flour for potable ethanol production was developed at lab (1 L) and pilot scale (15 L and 1000 L). Cassava flour (CF) was mixed with tap water to obtain a concentration of 270 g/L dry matter. Sequentially, the mixture of a native starch hydrolyzing enzyme containing a mixture of alpha–amylase and gluco-amylase (Stargen 002 at 2565 GAU/kg CF), gluco-amylase (Amigase Mega L at 0.105% w/w), active dry yeast Saccharomyces cerevisiae (Red Ethanol at 3,5 × 10^7 cells/ml), KH2PO4 (9,9 mM) and urea (16.0 mM) was added into cassava slurry. The SLSF-VHG process including three steps of liquef…

Occurrence of selected antibiotics and antiretroviral drugs in Nairobi River Basin, Kenya.

2015

In this paper, we investigated the occurrence of three antibiotics (sulfamethoxazole, trimethoprim and ciprofloxacin) and three antiretroviral (lamivudine, nevirapine and zidovudine) drugs in the Nairobi River Basin, Kenya. The analytical procedure involved extraction using solid phase extraction followed by liquid chromatography-electrospray ionization tandem mass spectrometry (SPE-LC-ESI-MS/MS). In this study, 40 sites were selected for sampling, including 38 sites along the rivers and 2 wastewater treatment effluent sites. All the studied compounds were detected with sulfamethoxazole having the highest detection frequency of 97.5% and ciprofloxacin had the lowest at 60%. The results show…

Effect of amorphous sequences on the longitudinal acoustic modes in partially crystalline polymers. I. Transfer matrix method

1983

A novel theoretical scheme is developed which enables the determination of the LAM-like vibrations of polymer chains made up of crystalline and amorphous parts as they occur in partially crystalline structures. The boundary conditions effective at the junction points are formulated in terms of the compliances of the associated amorphous sequences. These compliances can be derived from their eigenfrequencies and eigenvectors in a disconnected state. The treatment uses a matrix formalism which can be extended to include bending and torsional motions in a general state of vibration of the crystalline stem. A first numerical example demonstrates that the LA mode of a crystalline stem can be str…

El arma del crimen

2009

Efectos perversos de la multiculturalidad

2005

Los excluidos, ciudadanos

1998

Effect of TiO2 on the mullite formation and mechanical properties of alumina porcelain

2010

Abstract The effect of adding TiO 2 to standard alumina porcelain on its microstructure and flexural strength was investigated. A series of alumina porcelain bodies containing increasing amounts of TiO 2 were prepared by extruding mixtures of raw materials and TiO 2 . Porcelain rods were fired under industrial scheduling in a manufacturing kiln. The overall degree of crystalline and amorphous phase content within the porcelain bodies was quantitatively determined using a Rietveld analysis. Results indicated a higher amount of mullite formation in porcelain bodies containing TiO 2 . Examination of the product materials using field emission scanning electron microscopy showed a high density o…

Recent visigothic coin findings. Gold and bronze in the north of Cáceres

2017

El artículo pretende documentar una serie de monedas visigodas de oro y bronce encontradas fortuitamente dentro de la provincia de Cáceres, todas ellas de forma aislada y en solitario. La procedencia exacta de todas las piezas no se conoce del todo, aunque están circunscritas con seguridad a Cáceres. Además, dos de las monedas son inéditas: un triente pseudo-imperial a nombre de Justiniano I y un tremís de Égica y Witiza procedente de Acci. The paper aims to document a series of Visigoth gold and bronze coins fortuitously found in the province of Cáceres, all of them isolated and alone. The exact origin of all the coins is not fully known, but it is confined surely within Cáceres. Furthermo…