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排序方式: 共有812条查询结果,搜索用时 15 毫秒
31.
This review draws on knowledge for the treatment of heavy‐metal leachate in contaminated mine sites. Mine waste rock dumps and tailings generate a continuous stream of metalliferous and saline leachate over the long term. The mining industry has many legacy sites, which have compromised aquatic ecosystems and groundwater because of heavy‐metal contamination. Chemical and engineering methods are available and have been extensively utilised. However, these methods require intensive energy and often produce substantial volumes of secondary waste. We therefore argue in favour of phytoremediation as a sustainable remediation strategy leading towards efficient and sustainable metal removal and immobilisation through constructed wetlands. 相似文献
32.
Julie Chandra C. S. Bipinbal P. K. Dileep P. Sasi Sreesha Raman Vidya Bindu Sharmila T. K. Narayanankutty Sunil K. 《SILICON》2022,14(13):7919-7932
Silicon - Nanosilica was synthesized from a low cost raw material, olivine by a more sustainable and cost effective method. The pure nanosilica obtained was amorphous in nature with a surface area... 相似文献
33.
Senthil Kumar Raman Heuy Dong Kim 《Journal of Mechanical Science and Technology》2018,32(3):1099-1104
The accuracy of the thermodynamic properties prediction from the different Equation of state (EOS) varies upon the range of temperature and pressure. Despite the variety of EOS available, there is no de facto for selecting an EOS for particular computational modeling. The EOS model recently developed by Kumar and Kim (K-K EOS) determines more accurately the thermodynamic properties of CO2 than earlier models. In this present study, K-K EOS is successfully implemented in the computational analysis of compressible supercritical CO2 flow (S-CO2) in the thermodynamic region near and away from the vapour-liquid critical point. Computational results of SCO2 flow with the real gas properties predicted with the K-K EOS is compared with Span and Wagner (SW EOS) and ideal EOS. 相似文献
34.
Deepeak N. Shah Bharat B. Chattoo Raman M. Kothari Mahabaleshwar V. Hegde 《Starch - St?rke》1993,45(3):104-109
Using Yarrowia lipolytica (DS-1), secretion of citric acid is studied as a function of carbon sources such as glucose, fructose, hydrol, sucrose, cane sugar molasses, kerosene (all available commercially) and tapioca starch hydrolysate, invert sucrose and invert cane sugar molasses (all prepared in laboratory). On the basis of their acceptability by DS-1 for citric and isocitric acid secretion, it is concluded that (a) sucrose and cane sugar molasses (with/without inversion) served as poor carbon sources, (b) fructose, hydrol, impure tapioca starch hydrolysate (96 DE w/w) and invert sucrose served as relatively better carbon sources and (c) purified tapioca starch hydrolysate (96 DE w/w) was the best carbon source to substitute glucose by giving comparable (75%) efficiency of conversion and economical advantage. 相似文献
35.
D. J. Davidson S. S. Sai Raman M. V. Lototsky O. N. Srivastava 《International Journal of Hydrogen Energy》2003,28(12):1425-1431
This paper deals with computer simulation of the P–C isotherms of some ZrFe2 type (Zr(Fe1−xCrx)2, Zr1−xTixFe1.4Cr0.6, Zr1−2xMmxTixFe1.4Cr0.6 : x00.4) of hydrogen storage materials. A feasible mathematical model has been developed to simulate the P–C isotherms. The randomized variables in the model applied for simulating the P–C isotherms of the above-mentioned ZrFe2 type hydrogen storage materials correspond to change in enthalpy (ΔH) and entropy (ΔS) of hydride formation. Several ZrFe2 type materials as in above have been synthesized and their P–C isotherms, enthalpy and entropy change has been evaluated experimentally in order to have input data for simulation. A special software was developed to simulate the P–C isotherms using the said model. A close match between the experimentally observed and simulated P–C isotherms for the above said ZrFe2 type alloys has been obtained. 相似文献
36.
R. Raman Ashok Kumar Kapoor Shiv Kumar Akhilesh Pandey 《Journal of Electronic Materials》2009,38(10):2046-2051
Colloidal silver is observed to affect the transmittance of p-type Cd1−y
Zn
y
Te (CZT) single-crystal substrate material at room temperature. The optical transmittance spectra have been analyzed in the
near-infrared (NIR) and mid-infrared (MIR) regions. The transmittance characteristics of CZT showed significant reduction
in absorption due to split-off valance band transitions in the NIR region and intervalence band absorption in the MIR region
upon coating CZT substrates with silver paste. This reduction in absorption has been explained to be due to the compensation
of the acceptor defects (native and foreign). Silver atoms incorporated from the silver coating help in compensation of these
defects. A similar effect on transmittance characteristics of mercury cadmium telluride (MCT) epilayers grown on CZT substrates
after coating silver paste on the CZT substrate side was also observed. An improvement in the transmittance of CZT substrates
after the application of silver paste was observed. A similar improvement in transmittance is usually achieved by annealing
the substrates in a Cd/Zn atmosphere. The results are explained by considering the formation of neutral complexes of acceptors
(cadmium vacancies) and the interstitial silver. This study also points to the important conclusion that silver paste on CZT
should be applied with caution for measurement purposes since it diffuses even at room temperature and modifies the optical
characteristics. 相似文献
37.
38.
Manoj Gaur Jaya Lohani R. Raman V.R. Balakrishnan P. Raghunathan S.V. Eswaran 《Synthetic Metals》2010,160(19-20):2061-2064
Diode devices (glass/ITO/polymer/Al) have been fabricated using poly (3-hexylthiophene) (P3HT) crosslinked with two different biaryl crosslinkers. Crosslinking was performed by exposing the thin films with different wt% of crosslinker to UV irradiation and progress of crosslinking was monitored by IR spectroscopy. An increase in hole mobility of two orders of magnitude has been observed after crosslinking. 相似文献
39.
Sarvesh Pal R. K. Singh Raman R. N. Ibrahim 《Metallurgical and Materials Transactions A》2012,43(6):1944-1955
Stress corrosion cracking tests were conducted using Bayer solutions of different chemistry at different temperatures for
extraction of alumina from bauxite ores. The validity of the commonly used caustic cracking susceptibility (CS) diagram for
steels exposed to plain caustic solutions was assessed by testing the notched and precracked specimens. This study presents
first results toward the development of a model susceptibility diagram for actual Bayer solutions, and for improved applicability
of the traditional plain caustic diagram. For mechanistic understanding of caustic cracking, tests were also carried out under
imposed electrochemical conditions. 相似文献
40.
Jagadeeswari Sivanadanam Ramesh Mukkamala Sudip Mandal Raman Vedarajan Noriyoshi Matsumi Indrapal Singh Aidhen Kothandaraman Ramanujam 《International Journal of Hydrogen Energy》2018,43(9):4691-4705
Six triphenylamine-based dyes were explored for their application in dye-sensitized solar cells (DSSCs). Dyes 1–3 and dyes 4–6 possess cyanoacrylic acid (C-acceptor) and rhodanine-3-acetic acid (R-acceptor), respectively. Stilbene (in dyes 2 and 5) and bis(styryl)benzene (in dyes 3 and 6) were used as π-spacers. There is no π-spacer in the dye 1 and 4. To elucidate the role of π-spacers, optical, electrochemical, and photovoltaic properties of the dyes were studied. Among C-acceptor dyes, dye 2 exhibits the highest light-to-electricity conversion efficiency of 4.45%, followed by dye 3 (4.16%). Similarly, among R-acceptor dyes, dye 5 is the best. These results indicate that stilbene is a better π-spacer over bis(styryl)benzene. Although bis(styryl)benzene could extend the light absorption range (in dye-adsorbed TiO2 film), its tendency to promote intermolecular π-π stacking is possibly the reason for its poor performance in DSSCs. Furthermore, the conjugation break in the R-acceptor moiety attached to the TiO2 surface limits the electron injection of R-acceptor dyes poorer than C-acceptor dyes. Density functional theory calculations were performed for the dye-(TiO2)8 cluster, assuming a bidentate chelation of a carboxylic acid group with Ti4+ of TiO2 anatase. The natural bond orbital (NBO) analysis indicated relatively more electron-accepting ability of cyanoacrylic acid over rhodanine-3-acetic acid. 相似文献