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1.
Phys Rev Lett ; 124(7): 073402, 2020 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-32142338

RESUMEN

We analyze the physics of self-bound droplets in a doubly dipolar Bose-Einstein condensate composed by particles with both electric and magnetic dipole moments. Using the particularly relevant case of dysprosium, we show that the anisotropy of the doubly dipolar interaction potential is highly versatile and nontrivial, depending critically on the relative orientation and strength between the two dipole moments. This opens novel possibilities for exploring intriguing quantum many-body physics. Interestingly, by varying the angle between the two dipoles we find a dimensional crossover from quasi-one-dimensional to quasi-two-dimensional self-bound droplets. This opens a so far unique scenario in condensate physics, in which a dimensional crossover is solely driven by interactions in the absence of any confinement.

2.
Environ Res ; 147: 249-58, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26918838

RESUMEN

Sustainable valorization processes for selective recovery of pure copper nanopowder from Indium-Tin-Oxide (ITO) etching wastewater by various wet chemical reduction processes, their chemistry has been investigated and compared. After the indium recovery by solvent extraction from ITO etching wastewater, the same is also an environmental challenge, needs to be treated before disposal. After the indium recovery, ITO etching wastewater contains 6.11kg/m(3) of copper and 1.35kg/m(3) of aluminum, pH of the solution is very low converging to 0 and contain a significant amount of chlorine in the media. In this study, pure copper nanopowder was recovered using various reducing reagents by wet chemical reduction and characterized. Different reducing agents like a metallic, an inorganic acid and an organic acid were used to understand reduction behavior of copper in the presence of aluminum in a strong chloride medium of the ITO etching wastewater. The effect of a polymer surfactant Polyvinylpyrrolidone (PVP), which was included to prevent aggregation, to provide dispersion stability and control the size of copper nanopowder was investigated and compared. The developed copper nanopowder recovery techniques are techno-economical feasible processes for commercial production of copper nanopowder in the range of 100-500nm size from the reported facilities through a one-pot synthesis. By all the process reported pure copper nanopowder can be recovered with>99% efficiency. After the copper recovery, copper concentration in the wastewater reduced to acceptable limit recommended by WHO for wastewater disposal. The process is not only beneficial for recycling of copper, but also helps to address environment challenged posed by ITO etching wastewater. From a complex wastewater, synthesis of pure copper nanopowder using various wet chemical reduction route and their comparison is the novelty of this recovery process.


Asunto(s)
Cobre/aislamiento & purificación , Indio/análisis , Residuos Industriales/análisis , Nanopartículas , Reciclaje/métodos , Compuestos de Estaño/análisis , Aguas Residuales/química , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Polvos , Soluciones
3.
Environ Res ; 140: 704-13, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26094059

RESUMEN

Dust generated during metal organic vapor deposition (MOCVD) process of GaN based semiconductor power device industry contains significant amounts of gallium and indium. These semiconductor power device industry wastes contain gallium as GaN and Ga0.97N0.9O0.09 is a concern for the environment which can add value through recycling. In the present study, this waste is recycled through mechanochemical oxidation and leaching. For quantitative recovery of gallium, two different mechanochemical oxidation leaching process flow sheets are proposed. In one process, first the Ga0.97N0.9O0.09 of the MOCVD dust is leached at the optimum condition. Subsequently, the leach residue is mechanochemically treated, followed by oxidative annealing and finally re-leached. In the second process, the MOCVD waste dust is mechanochemically treated, followed by oxidative annealing and finally leached. Both of these treatment processes are competitive with each other, appropriate for gallium leaching and treatment of the waste MOCVD dust. Without mechanochemical oxidation, 40.11 and 1.86 w/w% of gallium and Indium are leached using 4M HCl, 100°C and pulp density of 100 kg/m(3,) respectively. After mechanochemical oxidation, both these processes achieved 90 w/w% of gallium and 1.86 w/w% of indium leaching at their optimum condition.


Asunto(s)
Galio/química , Residuos Industriales , Nitrógeno/química , Compuestos Orgánicos/química , Semiconductores , Microscopía Electrónica de Rastreo , Oxidación-Reducción , Espectrometría por Rayos X
4.
Environ Res ; 138: 401-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25769129

RESUMEN

Waste dust generated during manufacturing of LED contains significant amounts of gallium and indium, needs suitable treatment and can be an important resource for recovery. The LED industry waste dust contains primarily gallium as GaN. Leaching followed by purification technology is the green and clean technology. To develop treatment and recycling technology of these GaN bearing e-waste, leaching is the primary stage. In our current investigation possible process for treatment and quantitative leaching of gallium and indium from the GaN bearing e-waste or waste of LED industry dust has been developed. To recycle the waste and quantitative leaching of gallium, two different process flow sheets have been proposed. In one, process first the GaN of the waste the LED industry dust was leached at the optimum condition. Subsequently, the leach residue was mixed with Na2CO3, ball milled followed by annealing, again leached to recover gallium. In the second process, the waste LED industry dust was mixed with Na2CO3, after ball milling and annealing, followed acidic leaching. Without pretreatment, the gallium leaching was only 4.91 w/w % using 4M HCl, 100°C and pulp density of 20g/L. After mechano-chemical processing, both these processes achieved 73.68 w/w % of gallium leaching at their optimum condition. The developed process can treat and recycle any e-waste containing GaN through ball milling, annealing and leaching.


Asunto(s)
Residuos Electrónicos/análisis , Galio/análisis , Reciclaje/métodos , Administración de Residuos/métodos , Residuos Industriales/análisis
5.
Transbound Emerg Dis ; 67(2): 510-517, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31692237

RESUMEN

During the years 2010-2018, avipoxvirus (APV) outbreaks were observed in the domestic chickens and pigeons present in the eastern Indian state of Odisha. Based on typical pox lesions, followed by molecular techniques, the overall morbidity was found to be 18%-19.23% and 16.92%-23% in chickens and pigeons, respectively. The cutaneous forms of the disease were observed with varied rates of mortality, being 47.36%-52.77% in chickens and 39.13%-92% in pigeons. PCR amplification targeting the viral P4b core protein-coding gene and the DNA polymerase gene confirmed the presence of APV strains in 10 birds. Subsequent phylogenetic analysis of these two genes confirmed that the circulating strains were members of APV clade A. The subclade analysis revealed the introduction of A1 and A3 subclades in Indian chickens and pigeons, respectively. This study is the first molecular record of APVs circulating in eastern Indian birds (Odisha) and involves the first use of the polymerase gene to reveal the circulating clades of Indian APVs.


Asunto(s)
Avipoxvirus/clasificación , Enfermedades de las Aves/virología , Pollos/virología , Columbidae/virología , Infecciones por Poxviridae/veterinaria , Animales , Avipoxvirus/genética , Enfermedades de las Aves/epidemiología , India/epidemiología , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Infecciones por Poxviridae/epidemiología , Infecciones por Poxviridae/virología
6.
Waste Manag ; 57: 207-214, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26944866

RESUMEN

Considering indium scarcity, the end-of-life (EOL) LCD, which accounts for up to 90% of market share can be a feasible secondary resource upon successful recycling. In the preferred hydrometallurgical process of such critical metals, leaching is the essential primary and essential phase has been investigated. In this process, LCD was mechanically separated along with other parts from EOL TVs through a smartly engineered process developed at our institute, Institute for Advanced Engineering (IAE), the Republic of Korea. After removing plastics and metals from the LCD, it was mechanically shredded for size reduction. The mechanically shredded LCD waste was leached with HCl for recovery of indium. Possible leaching parameters such as; effect of acid concentration, pulp density, temperature and effect of oxidant H2O2 concentration were investigated to identify the best conditions for indium extraction. Indium (76.16×10-3g/L) and tin (10.24×10-3g/L) leaching was achieved at their optimum condition, i.e. lixiviant of 5M HCl, a pulp density of 500g/L, temperature 75°C, agitation speed of 400rpm and time for 120min. At optimum condition the glass, plastic and the valuable metal indium have completely been separated. From indium enriched leach liquor, indium can be purified and recovered through hydrometallurgy.


Asunto(s)
Residuos Electrónicos , Indio/aislamiento & purificación , Reciclaje/métodos , Peróxido de Hidrógeno/química , Cinética , Cristales Líquidos , Metalurgia/métodos , Plásticos , Temperatura
7.
Waste Manag ; 45: 351-60, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26210233

RESUMEN

Materials flow analysis of neodymium, status of rare earth elements (REEs) in the Republic of Korea has been investigated. Information from various resources like the Korean Ministry of Environment, Korea international trade association, United Nations Commodity Trade Statistics Database and from individual industry were collected and analyzed for materials flow analysis of neodymium. Demand of neodymium in the Republic of Korea for the year 2010 was 409.5 tons out of which the majority of neodymium, i.e., 68.41% was consumed by domestic electronics industry followed by medical appliances manufacturing (13.36%). The Republic Korea is one of the biggest consumer and leading exporter of these industrial products, absolutely depends on import of neodymium, as the country is lacking natural resources. The Republic of Korea has imported 325.9 tons of neodymium permanent magnet and 79.5 tons of neodymium containing equipment parts mainly for electronics, medical appliances, and heavy/light vehicles manufacturing industry. Out of which 95.4 tons of neodymium permanent magnet get exported as an intermediate product and 140.6 tons of neodymium in the form of consumable products get exported. Worldwide the neodymium is at the high end of supply chain critical metal because of increasing demand, scarcity and irreplaceable for technological application. To bring back the neodymium to supply stream the recycling of end of life neodymium-bearing waste can be a feasible option. Out of total domestic consumption, only 21.9 tons of neodymium have been collected and subsequently recycled. From material flow analysis, the requirement for an efficient recycling system and element-wise material flow management for these REEs in the Republic of Korea were realized and recommended.


Asunto(s)
Neodimio/análisis , Reciclaje/métodos , Administración de Residuos/métodos , República de Corea
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