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991.
By‐products of various industrial fermentations can be good adsorbents for removing hazardous dyes from wastewater. However, after biosorption, regeneration of biomass is essential to minimize the solid waste generation or else the dye laden biomass should be suitably disposed off. In the present work, experiments were conducted on the Acid Navy Blue and Methylene Blue dyes which were biosorbed to the fungal biomass (strain closely related to Aspergillus lentulus) produced on corncob as the substrate through solid state fermentation. In order to dispose the dye laden biomass, it was vermicomposted along with cow dung (CD) employing Eisenia fetida. Results indicated that the dye laden biomass was not lethal toward the earthworms as no mortality was observed. However, as compared with control experiments (where dye laden biomass was absent), the reproductive potential of the earthworms was affected. Nevertheless, further investigations on optimization of biomass and CD ratios can facilitate vermicomposting as a potential route for disposing dye laden biomass. 相似文献
992.
993.
The thermosolutal-convective instability of a composite stellar atmosphere is considered in the presence of variable horizontal magnetic field and collisional effects. The criteria for monotonic instability are obtained which generalize the criterion derived for thermal-convective instability in the absence of above effects. 相似文献
994.
Anna M. Nobili Gian Luca Comandi Suresh Doravari Donato Bramanti Rajeev Kumar Francesco Maccarrone Erseo Polacco Slava G. Turyshev Michael Shao John Lipa Hansjoerg Dittus Claus Laemmerzhal Achim Peters Jurgen Mueller C. S. Unnikrishnan Ian W. Roxburgh Alain Brillet Christian Marchal Jun Luo Jozef van der Ha Vadim Milyukov Valerio Iafolla David Lucchesi Paolo Tortora Paolo De Bernardis Federico Palmonari Sergio Focardi Dino Zanello Salvatore Monaco Giovanni Mengali Luciano Anselmo Lorenzo Iorio Zoran Knezevic 《Experimental Astronomy》2009,23(2):689-710
“Galileo Galilei” (GG) is a small satellite designed to fly in low Earth orbit with the goal of testing the Equivalence Principle—which
is at the basis of the General Theory of Relativity—to 1 part in 1017. If successful, it would improve current laboratory results by 4 orders of magnitude. A confirmation would strongly constrain
theories; proof of violation is believed to lead to a scientific revolution. The experiment design allows it to be carried
out at ambient temperature inside a small 1-axis stabilized satellite (250 kg total mass). GG is under investigation at Phase
A-2 level by ASI (Agenzia Spaziale Italiana) at Thales Alenia Space in Torino, while a laboratory prototype (known as GGG)
is operational at INFN laboratories in Pisa, supported by INFN (Istituto Nazionale di fisica Nucleare) and ASI. A final study
report will be published in 2009. 相似文献
995.
The effect of ionic interactions on the kinetics of disproportionation of HO2, and the oxidation of Fe(II) and Cu(I) has been examined. The interactions of O2 with Mg2+ and Ca2+ ions in seawater increases the lifetime by 3–5 times compared to water. The effect of OH− on the oxidation of Fe(II) in water and seawater shows a second degree dependence from 5 to 45°C. The effect of salinity on the oxidation of Fe(II) was found to be independent of temperature, while the effect of temperature was found to be independent of salinity. The energy of activation for the overall rate constant was found to be 7 ± 0.5 kcal mol−1.The effect of pH, temperature, salinity and ionic composition on the oxidation of Cu(I) has also been examined. In NaCl solutions from 0.5 to 6 M, the log k for the oxidation was a linear function of pH (6–8) with a slope of 0.2 ± 0.05. The reaction was strongly dependent on the Cl− concentration with variation of
from 0.3 to 340 min from 0.5 to 6 M Cl−. The rates of oxidation of Cu+ and CuCl0 responsible for these effects are dependent upon ionic strength. The energy of activation for the reaction was 8.5–9.9 kcal mol−1 from 0.5 to 6 M. Studies of the oxidation in various NaX salts (X = I−, Br− and Cl−) give rates in the order Cl− > Br− > I− as expected, due to complex formation of Cu+ with X−. 相似文献
996.
Kunwar Mrityunjai Sharma Debanjan Guha Roy Praksh Kumar Singh Lakshmi Kant Sharma Trilok Nath Singh 《Arabian Journal of Geosciences》2017,10(16):362
Understanding the flow behavior through fractures is critically important in a wide variety of applications. In many situations, the fluid flow can be highly irregular and non-linear in nature. Numerical simulation can be employed to simulate such conditions which are difficult to replicate in laboratory experiments. Therefore, a parametric study has been conducted on the fluid flow through micro-fracture over a large range of inlet pressure, fluid density, fluid viscosity, temperature, joint roughness coefficient (JRC), and fracture using finite element analysis. Irregular fracture profiles were created using Barton’s joint roughness coefficient. The Navier-Stokes (NS) equation was used to simulate the flow of water in those micro-fractures. The result showed that the fracture, fluid, and ambient conditions have a wide and varied effect on the fluid flow behavior. The interrelationship between these parameters was also studied. The model simulation provided result in the form of velocity and pressure drop profile, which can be used to determine the behavior of flow under different condition. The volumetric flow was calculated for each condition and has been plotted against the corresponding parameter to study the interrelationship. 相似文献
997.
Short-term geomorphic and hydrologic effects of subsidence induced by longwall mining under Burnout Creek, Utah were evaluated.
During the year after longwall mining, 0.3–1.5 m of subsidence was measured near impacted reaches of the mountain stream channel.
The major channel changes that occurred in a 700-m reach of Burnout Creek that was subsided from 1992 to 1993 were: (1) increase
in lengths of cascades and to a lesser extent glides; (2) increases in pool length, numbers and volumes; (3) increase in median
particle diameter of bed sediment in pools; and (4) some constriction in channel geometry. Most of the changes appeared short-lived,
with channel recovery approaching pre-mining conditions by 1994. In a 300-m reach of the South Fork that was subsided from
1993 to 1994, only channel constriction was observed, although any impacts on pool morphology may have been confounded by
heavy grazing in the riparian reaches during the dry summer of 1994. Similar near-channel sedimentation and loss of pool volume
between 1993 and 1994 were noted throughout Burnout Creek and in adjacent, unmined James Creek. Subsidence during the 3-year
period had no effect on baseflows or near-channel landslides.
Received: 10 April 1998 · Accepted: 21 September 1998 相似文献
998.
Global regression relations for conversion of surface wave and body wave magnitudes to moment magnitude 总被引:1,自引:0,他引:1
A homogenous earthquake catalog is a basic input for seismic hazard estimation, and other seismicity studies. The preparation
of a homogenous earthquake catalog for a seismic region needs regressed relations for conversion of different magnitudes types,
e.g. m
b
, M
s
, to the unified moment magnitude M
w. In case of small data sets for any seismic region, it is not possible to have reliable region specific conversion relations
and alternatively appropriate global regression relations for the required magnitude ranges and focal depths can be utilized.
In this study, we collected global events magnitude data from ISC, NEIC and GCMT databases for the period 1976 to May, 2007.
Data for mb magnitudes for 3,48,423 events for ISC and 2,38,525 events for NEIC, M
s
magnitudes for 81,974 events from ISC and 16,019 events for NEIC along with 27,229 M
w
events data from GCMT has been considered. An epicentral plot for M
w
events considered in this study is also shown. M
s
determinations by ISC and NEIC, have been verified to be equivalent. Orthogonal Standard Regression (OSR) relations have
been obtained between M
s
and M
w
for focal depths (h < 70 km) in the magnitude ranges 3.0 ≤ M
s
≤ 6.1 and 6.2 ≤ M
s
≤ 8.4, and for focal depths 70 km ≤ h ≤ 643 km in the magnitude range 3.3 ≤ M
s
≤ 7.2. Standard and Inverted Standard Regression plots are also shown along with OSR to ascertain the validation of orthogonal
regression for M
s
magnitudes. The OSR relations have smaller uncertainty compared to SR and ISR relations for M
s
conversions. ISR relations between m
b
and M
w
have been obtained for magnitude ranges 2.9 ≤ m
b
≤ 6.5, for ISC events and 3.8 ≤ m
b
≤ 6.5 for NEIC events. The regression relations derived in this study based on global data are useful empirical relations
to develop homogenous earthquake catalogs in the absence of regional regression relations, as the events catalog for most
seismic regions are heterogeneous in magnitude types. 相似文献
999.
1000.
Santosh Kumar Sita Bora Umesh K. Sharma 《Journal of the Geological Society of India》2016,87(6):737-746
New field observations on granitoids and associated lithounits in some parts of Indus-Shyok Suture Zones have been documented in order to re-establish the geological relationships between various volcano-plutonic magmatic lithounits. Careful examination of outcrops and contact relationships between the various lithounits have pin-pointed the sequence of geological events. Field features of granitoids exposed along Leh-Saboo-Khardung_La suggest multiple pulses of mafic-felsic magma interactions (mingling to mixing) with almost 25% of the mafic to hybrid magma input in the evolution of the eastern part of Ladakh batholith. Along Khardung_La-Shyok-Diskit, thick sequence of volcanic lithounits is exposed, which dominantly consist of massive basaltic andesite, porphyritic andesite, dacite and rhyolite forming Khardung Formation. On the other hand Shyok Formation, dipping opposite to the Khardung Formation, composed predominantly of meta-sedimentary lithounits and subordinate amount of volcanic materials at present exposed level. Spectacular intrusive contacts of Ladakh granitoids with metavolcanics and meta-sedimentary country rocks of Shyok Formation near Diskit can be observed, which are manifested by ubiquitous xenoliths near the marginal parts. Although the nature of granitoid melt invasion into country-rocks was relatively winty, granitoid melt has produced leucogranite-pegmatite system because of devolatization and decompression effects. Frequent xenoliths of porphyritic andesite and dacite roof pendants are being reported in Tirit granitoids, which strongly suggest sub-volcanic emplacement of granitoid melt, extensive assimilation and roof collapse of overlying volcanic materials. It is more likely that the xenoliths hosted in Tirit granitoids belong to Shyok volcanics. It is suggested that multiple pulses of coeval mafic and felsic magmatism occurred extensively and emplaced at differential crustal levels. 相似文献