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laser optogalvanic investigations of the Neon 6302 A transition

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原子与分子物理学报 2007年第B8期24卷 102-104页

作者： HAN Xianming l POZDIN V HARIDASS C misra P Department of Physics ＆ Astronomy Butler University Indianapolis IN 46208 ClOE Comell University Ithaca NY 14850 Department of Physical Sciences Belfry School Belfry KY 41514 Department of Physics ＆ Astronomy Howard University Washington D. C20059

The optogalvanic effect of neon, in the presence of CO gas, has been specifically investigated for the 630.2 nm transition. Our theoretical model, based on rate equations, predicts well the observed signals as a sum o... 详细信息

关键词：光电效应信号波形蒙特卡罗法激光

Development of a field enhanced photocatalytic device for biocide of coliform bacteria

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Journal of Environmental Sciences 2016年第6期28卷 38-44页

作者： Jeff M.Huber Krista l.Carlson Otakuye Conroy-Ben Mano misra Swomitra K.Mohanty Departments of Civil Engineering University of Utah Departments of Metallurgical Engineering University of Utah Departments of Chemical Engineering University of Utah

A field enhanced flow reactor using bias assisted photocatalysis was developed for bacterial disinfection in lab-synthesized and natural waters. The reactor provided complete inactivation of contaminated waters with flow rates of 50 ml/min. The device consisted of titanium dioxide nanotube arrays, with an externally applied bias of up to 6 V. light intensity, applied voltage, background electrolytes and bacteria concentration were all found to impact the device performance. Complete inactivation of Escherichia coli W3110（- 8 × 10^3CFU/ml） occurred in 15 sec in the reactor irradiated at 25 mW/cm^2 with an applied voltage of 4 V in a 100 ppm NaCl solution. Real world testing was conducted using source water from Emigration Creek in Salt lake City, Utah. Disinfection of natural creek water proved more challenging, providing complete bacterial inactivation after 25 sec at 6 V. A reduction in bactericidal efficacy was attributed to the presence of inorganic and organic species, as well as the increase in robustness of natural bacteria.

关键词： Titanium dioxide Nanotubes Immobilized Photocatalysis Escherichia coli Inactivation

Absolute parameters and observed flares in the M-type detached eclipsing binary 2MASS J04100497+2931023

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Research in Astronomy and Astrophysics 2021年第5期21卷 130-138页

作者： Gang Meng li-Yun Zhang Qing-Feng Pi liu long Xianming l.Han misra Prabhakar College of Physics&Guizhou Provincial Key laboratory of Public Big Data Guizhou UniversityGuiyang 550025China Key laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China College of Medicine Guizhou University of Traditional Chinese MedicineGuiyang 550025China Department of Astronomy Beijing Normal UniversityBeijing 100875China Dept.of Physics and Astronomy Butler UniversityIndianapolisIN 46208USA Department of Physics&Astronomy Howard UniversityWashington DC 20059USA

The eclipsing binary 2 MASS J04100497+2931023(J04100497+2931023) is classified its spectral type of M0±2 V on basis of a low-resolution spectral survey by the large Sky Area Multi-Object Fiber Spectroscopic Telescope(lAMOST). The low-resolution spectra exhibit strong single-peak emission in the Hα line. We obtained the radial velocities of this binary by means of the Cross-Correlation Function method from the lAMOST medium-resolution spectra. Both components of J04100497+2931023 indicate strong emissions in the Hα line. We performed follow-up photometric observations of J04100497+2931023 using the Xinglong 85 cm telescope of National Astronomical Observatories, Chinese Academy of Sciences. We obtained its full light curve in V RI filters. We first determined their absolute parameters from simultaneously radial velocity and light curves by the Wilson-Devinney program. From our new light curves, we detected three flares for the first time, including one convective flare. The amplitudes,durations, energies, and spectral indices of three flares were also determined. J04100497+2931023 was monitored for approximately 29 h, which indicates that the flare rate is 0.1 flare per hour. We conclude that J04100497+2931023 is a low-mass detached eclipsing binary with strong magnetic activity.

关键词： binaries:eclipsing stars:flare star:low-mass stars:J04100497+2931023

Microstructural Evolution and Properties of a High Strength Steel with Different Direct Quenching Processes

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Journal of Iron and Steel Research International 2015年第4期22卷 344-351页

作者： Feng lU Chao WANG long l Zhao-dong WANG Guo-dong WANG Raja Devesh Kumar misra State Key laboratory of Rolling and Automation Northeastern University Department of Metallurgical and Materials Engineering University of Texas at El Paso

A high strength low alloy steel with low carbon equivalent was selected for simulating online direct quench- ing and coiling （DQ-C） process. The influence of stop quenching temperature on mechanical properties and micro- structures was studied and compared with normal direct quenching and tempering （DQ-T） process. The study con- firmed that required mechanical properties were obtained for both the processes. Properties of the experimental steel with DQ-C process could reach the same level as that of DQ-T process in general. In the DQ-C process, strength de- creased with increase in stop quenching temperature. Martensite was obtained and experienced an aging process at stop quenching temperature below Mi. On fast cooling below Mi, martensite was partially transformed and carbon partitioning occurred during slow cooling. The reduction in solid solution carbon and increased amount of retained austenite led to lower strength compared with the DQ-T process. DQ-C process was more favorable for microalloy carbide precipitation. However, impact toughness under different cooling conditions was adequate because of low car- bon equivalent and refined microstructure.

关键词： high strength steel direct quenching slow cooling carbon partitioning precipitation

Nanoscale deformation of multiaxially forged ultrafine-grained Mg-2Zn-2Gd alloy with high strength-high ductility combination and comparison with the coarse-grained counterpart

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Journal of Materials Science & Technology 2018年第2期34卷 311-316页

作者： K. li V.S.Y.Injeti P. Trivedi l.E. Murr R.D.K. misra Department of Metallurgical Materials and Biomedical Engineering University of Texas at El Paso 500 W. University Avenue El Paso TX 79968-0521 USA

Cold processing of magnesium （Mg） alloys is a challenge because Mg has a hexagonal close-packed （HCP） lattice with limited slip systems, which makes it difficult to plastically deform at low temperature. To address this challenge, a combination of annealing of as-cast alloy and multi-axial forging was adopted ro obtain isotropic ultrafine-grained （UFG） structure in a lean Mg-2Zn-2Gd alloy with high strength （yield strength： ~227 MPa）-high ductility （% elongation：～30%） combination. This combination of strength and ductility is excellent for the lean alloy, enabling an understanding of deformation processes in a formable high strength Mg-rare earth alloy. The nanoscale deformation behavior was studied via nanoindentation and electron microscopy, and the behavior was compared with its low strength （yield strength：～46 MPa） - low ductility （% elongation：～7%） coarse-grained （CG） counterpart. In the UFG alloy, extensive dislocation slip was an active deformation mechanism, while in the CG alloy, mechanical twinning occurred. The differences in the deformation mechanisms of UFG and CG alloys were reflected in the discrete burst in the load-displacement plots. The deformation of Mg-2Zn-2Gd alloys was significantly influenced by the grain structure, such that there was change in the deformation mechanism from dislocation slip （non-basal slip） to nanoscale twins in the CG structure. The high plasticity ofUFG Mg alloy involved high dislocation activity and change in activation volume.

关键词： Magnesium alloy Ultrafine-grained Nanoscale deformation

The kilosecond variability of X-ray sources in nearby galaxies

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Research in Astronomy and Astrophysics 2013年第12期13卷 1445-1454页

作者： Soma Mandal Ranjeev misra Gulab C.Dewangan Department of Physics Taki Government College Inter-University Centre for Astronomy and Astrophysics

Chandra observations of 17 nearby galaxies were analyzed and 166 bright sources with X-ray counts 〉 100 were chosen for temporal analysis. Fractional root mean square （rms） variability amplitudes were estimated for light curves, binned at 4 kilosecond （ks）, with length 〈 40 ks. While there are nine ultra-luminous X- ray sources （UlXs） with unabsorbed luminosity （in the 0.3-8.0 keV band） l 〉 1039 erg s-1 in the sample for which the fractional rms variability is constrained to be 〈 10%, only two of them show variability. One of the variable UlXs exhibits a secular transition and has an ultra-soft spectrum with temperature - 0.3 keV while the other is a rapidly varying source in NGC 0628, which has previously been com- pared to the Galactic microquasar GRS 1915＋105. These results seem to indicate that UlXs are typically not highly variable on ks timescales, except for some ultra-soft ones. Among the relatively low luminosity sources （l - 10^38 erg s-1）, we find five of them to be variable. Apart from an earlier known source in NGC 1569, we identify a source in NGC 2403 that exhibits persistent high amplitude fluctuations. In general, the variability of the sources does not seem to be correlated with hardness, which indicates that they may not be due to variations in any absorbing material, but instead could reflect instabilities in the inner accretion disk.

关键词： galaxies: general --X-rays: binaries

Comprehensive spectral analysis of Cyg X-1 using RXTE data

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Research in Astronomy and Astrophysics 2012年第10期12卷 1427-1438页

作者： Rizwan Shahid Ranjeev misra S.N.A.Jaaffrey Department of Physics M.L.Sukhadia UniversityUdaipur-313001India Inter University Centre for Astronomy and Astrophysics Pune-411007India

We analyze a large number （〉 500） of pointed Rossi X-Ray Timing Explorer （RXTE） observations of Cyg X- 1 and model the spectrum of each one. A subset of the observations for which there is a simultaneous reliable measure of the hardness ratio by the All Sky Monitor shows that the sample covers nearly all the spectral shapes of Cyg X-1. Each observation is fitted with a generic empirical model consisting of a disk black body spectrum, a Comptonized component whose input photon shape is the same as the disk emission, a Gaussian to represent the iron line and a reflection feature. The relative strength, width of the iron line and the reflection parameter are in general correlated with the high energy photon spectral index F. This is broadly consistent with a geometry where for the hard state （low F ~ 1.7） there is a hot in- ner Comptonizing region surrounded by a truncated cold disk. The inner edge of the disk moves inwards as the source becomes softer till finally in the soft state （high F 〉 2.2） the disk fills the inner region and active regions above the disk produce the Comptonized component. However, the reflection parameter shows non-monotonic behavior near the transition region （F ~ 2）, which suggests a more complex geometry or physical state of the reflector. In addition, the inner disk temperature, during the hard state, is on average higher than in the soft one, albeit with large scatter. These inconsistencies could be due to limitations in the data and the empirical model used to fit them. The flux of each spectral component is well correlated with F, which shows that unlike some other black hole systems, Cyg X- 1 does not show any hysteresis be- havior. In the soft state, the flux of the Comptonized component is always similar to the disk one, which confirms that the ultra-soft state （seen in other brighter black hole systems） is not exhibited by Cyg X-1. The rapid variation of the Compton amplifica- tion factor with F naturally explains the absence of spec

关键词： accretion accretion disks -- X-rays: binaries

Treatment of wheat straw using tannase and white-rot fungus to improve feed utilization by ruminants

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Journal of Animal Science and Biotechnology 2014年第2期5卷 222-229页

作者： Shailendra Raghuwanshi Swati misra Rajendra Kumar Saxena Department of Microbiology University of Delhi South CampusBenito Juarez Road New Delhi 110 021India

Background： Current research to enrich cattle feed has primarily focused on treatment using white rot fungi, while there are scarce reports using the enzyme tannase, which is discussed only in reviews or in the form of a hypothesis. In this context, the aim of the present study was to evaluate the effect of tannase on wheat straw （WS） and also the effect of lyophilized tannase at concentrations of 0.1%, 0.2%, and 0.3% （w/w） on WS followed by fermentation with Ganodermo sp. for 10 d and compared in relation to biochemical parameters, crude protein （CP） content, and nutritional value by calculating the C/N ratio in order to improve the nutritional value of cattle feed. Results： Penicillium charlesii, a tannase-producing microorganism, produced 61.4 IU/ml of tannase in 54 h when 2% （w/v） tannic acid （TA） was initially used as a substrate in medium containing （% w/v） sucrose （1.0）, NaNO3 （1.0）, and MgSO4 （0.08 pH, 5.0） in a 300-l fermentor （working volume 220 l）, and concomitantly fed with 1.0% （w/v） TA after 24 h. The yield of partially purified and lyophilized tannase was 5.8 IU/mg. The tannin-free myco-straw at 0.1% （w/w） tannase showed 37.8% （w/w） lignin degradation with only a 20.4% （w/w） decrease in cellulose content and the in vitro feed digestibility was 32.2%. An increase in CP content （up to 1.28-fold） along with a lower C/N ratio of 25.0%, as compared to myco-straw, was obtained. Conclusions： The use of tannin-free myco-straw has potential to improve the nutritional content of cattle feed. This biological treatment process was safe, eco-friendly, easy to perform, and was less expensive as compared to other treatment methods.

关键词： Ganoderma sp High energy cattle feed Tannase Tannin free myco-straw

Nitric oxide alleviates cadmium-impeded growth by limiting ROS accumulation in pea seedlings

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BIOCEll 2022年第12期46卷 2583-2593页

作者： EKHlAQUE A.KHAN HAMDINO M.I.AHMED MEENA misra PAllAVI SHARMA AMARENDRA N.misra MIRZA HASANUZZAMAN Department of life Sciences Central University of JharkhandRanchi835205India Department of Biotechnology Chaudhary Bansi Lal UniversityBhiwani127021India Horticulture Research Institute(HRI) Agricultural Research Center(ARC)Giza12619Egypt School of Environment and Sustainable Development Central University of GujratGandhinagar382030India School of Applied Sciences Centurion University of Technology and ManagementBhubaneswar752050India Department of Agronomy Faculty of AgricultureSher-e-Bangla Agricultural UniversityDhaka1207Bangladesh

Cadmium(Cd)causes oxidative stress,which leads to the oxidation of various biomolecules by the production of reactive oxygen species(ROS)to facilitate programmed cell death(PCD).The antioxidant defense system fails to detoxify ROS when it is produced in *** oxide(NO),a gaseous free radical and a phytohormone,regulates various physiological processes of ***,this work was undertaken to study the effects of the application of exogenous sodium nitroprusside(SNP,a NO donor)on growth parameters,oxidative stress,accumulation of secondary metabolites,and activities of antioxidant enzymes under Cd ***(50μM)and severe(200μM)Cd stress were applied to hydroponically grown pea(Pisum sativum l.)plants with or without 50μM *** Cd stress had a substantial impact on the *** effectiveness of NO in reducing Cd-induced negative effects on plant height,fresh weight,dry weight,protein content,nitrite content,nitrate reductase(NR)activity,catalase activity,and peroxidase activity were *** development,protein content,nitrite content,nitrate reductase(NR)activity,antioxidant defense systems disruption,overproduction of reactive oxygen species,and oxidative damage were *** antioxidant defense system(catalase and peroxidase activities)was activated by NO,which resulted in lower lipid peroxidation and lower hydrogen peroxide(H2O2)levels in Cd-exposed *** treatment boosted endogenous NO levels and NR activity in Cd-stressed plants while also enhanced proline levels to preserve osmotic *** presence of total phenols and flavonoids increased after SNP treatment,indicating that SNP enhanced stress recovery and boosted plant development in Cd-stressed plants.

关键词： Cadmium SNP Reactive oxygen species Oxidative stress Programmed cell death