1,044 research outputs found

    Shallow Deep Transitions of Neutral and Charged Donor States in Semiconductor Quantum Dots

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    We carry out a detailed investigation of neutral (D0D^0) and charged (DD^-) impurity states of hydrogen-like donors in spherical semiconductor quantum dots. The investigation is carried out within the effective mass theory (EMT). We take recourse to local density approximation (LDA) and the Harbola-Sahni (HS) schemes for treating many-body effects. We experiment with a variety of confining potentials: square, harmonic and triangular. We observe that the donor level undergoes shallow to deep transition as the dot radius (RR) is reduced. On further reduction of the dot radius it becomes shallow again. We term this non-monotonic behaviour \textbf{SHADES}. This suggests the possibility of carrier {\textbf{\textit{``freeze out''}}} for both D0D^0 and DD^-. Further, our study of the optical gaps also reveals a {\textbf{SHADES}} transition.Comment: 19 pages, 8 figures, Revised Versio

    Financial Performance of PSEs Post-disinvestment

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    India being a developing economy has adopted the concept of mixed economy wherein both the private and public sector were allowed to industrialize the country except few restricted sectors. PSEs controlled by the government played an instrumental role in servicing the country in infrastructure and public services. Since there were lots of political intervention because of which the PSEs derailed from the profit making objective and turned to drainage of wealth which were once referred to be temples of modern India. The PSEs were also suddenly exposed to Global competition which they were not used for operating under protected environment. The level playing field and competition affected the financial performances of PSEs. The paper elucidates the various financial ratios over a period of 10 years and analyzed the performance of the PSEs resurrecting focusing on other factors of their sustainability

    To Scale or Not to Scale : Self-Capacitance, ’’Hubbard U" and Quantum Dot Size ?

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    Surface Wear Studies in Some Materials Using α-induced Reactions

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    The radio-activity produced during the irradiation of 63,65Cu, 59Co, 93Nb and 121,123Sb targets with α-particles have been measured using activation technique. he yields of radioactive isotopic products 66,67,68 Ga, 61 Cu, 96g,mTc and 123,124,126I have been determined in the energy range ≈ 10-40 MeV using stacked foil Technique. Radioactive counting of samples was performed with a high-resolution gamma-spectrometer. As light ion beams produce an extremely narrow layer of activities in the surface of a material, these reactions may be useful for thin layer activation study

    Different types of mucormycosis: case series

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    Mucormycosis is the third invasive mycosis in order of importance after candidiasis and aspergillosis and is caused by fungi of the class Zygomycetes. The most important species causing Mucormycosis is Rhizopus arrhizus (oryzae). Identification of the agents responsible for mucormycosis is based on macroscopic and microscopic morphological criteria, carbohydrate assimilation and the maximum temperature compatible with its growth. The incidence of mucormycosis is approximately 1.7 cases per 1000 000 inhabitants per year. Clinical diagnosis of mucormycosis is difficult, and is often made at a late stage of the disease or post-mortem. We present here a series of five cases of different types of mucormycosis that were reported in our hospital till date. Of which three patients had good recovery and other two had a fatal outcome. Treatment of mucormycosis requires a rapid diagnosis, correction of predisposing factors, surgical resection or debridement as part of source control-and appropriate anti-fungal therapy. Liposomal amphotericin B is the drug of choice for this condition. The overall rate of mortality of mucormycosis is approximately 40%

    Recent Trends in Breeding of Tropical Grass and Forage Species

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    Germplasm enrichment in major tropical grasses and their characterization for emerging environmental challenges have been major focussed area in the recent past. Breeding efforts in tropical grasses are still limited to few selected species viz. Panicum spp, Cenchrus spp, Pennisetum spp and Bracharia spp and all other grasses use of land races for varietal development through selection have been major source of improvement. The pace of breeding efforts in the tropical grasses have been slowed because of many inherent characteristics viz. apomixis, poor seed set, high photo and thermo sensitivity often creating problem in designing and implementing an effective breeding programme. Identification of sexual lines using the modern tools of biotechnology have given new ways for the improvement in these group of crops. This paper provides overview of the recent development that has taken place in the germplasm collection, utilization and significant achievement made through genomic and biotechnological research

    Integrated effect of bio-organics with chemical fertilizer on growth, yield and quality of cabbage (Brassica oleracea var capitata)

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    This experiment focused on the effects of Pseudomonas fluorescens and humic acid in combination with three different levels of fertilizers on growth, yield and quality traits of Brassica oleracea L. Results indicated that treatments comprising 100% recommended fertilizers package coupled with seedling treated with Pseudomonas fluorescens and humic acid caused significantly higher plant height, dry matter in leaves (head), higher number of non-wrapper leaves and head yield (54.38 tonnes/ha) over 50% recommended dose of fertilizer with Pseudomonas fluorescens applied. Treatment 50% recommended dose of fertilizer applied with Pseudomonas fluorescens and humic acid was at par with 100% recommended dose of fertilizer alone. Total carbohydrate content in head (40.46%) was significantly higher with use of 100% recommended dose of fertilizer with Pseudomonas fluorescens and humic acid. Maximum protein content (18.54%) was noticed with application of 100% recommended dose of fertilizer with Pseudomonas fluorescens and humic acid that was 10.90% higher than recommended dose of fertilizer alone. Fibre content in head was improved remarkably with the use of Pseudomonas fluorescens and humic acid. Significantly higher content of ascorbic acid (34.51 mg/100 g) in head was also registered with application of 100% recommended dose of fertilizer with Pseudomonas fluorescens and humic acid

    Short-Term Effect of Forage Grasses on Carbon Sustainability, Fodder Security, and Soil Properties in Poor Soils of Semi-Arid India

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    Grasses are essential sources of fodder for livestock and provide options for climate resilience due to their broad range of adoption. They are also valuable resources for soil quality enhancement. Therefore, a six-year field study using nine grasses (2013 to 2019) was initiated in a semi-arid region of central India. The study aimed to assess the short-term impact of these nine grasses on soil carbon stock, selected soil physiochemical and biological properties, and green fodder yield. Results (after six years) revealed that a greater carbon stock (7.0 and 7.2 Mg ha–1), carbon sustainability index (71.6 and 89.3), and sustainable yield index for green fodder (0.89 and 0.91), respectively, were observed in lampagrass [Heteropogon contortus (L.)] and guineagrass [Megathyrsus maximus(Jacq.)]. These improvements could be due to the greater root length (1700 and 2220 cm plant–1) and root weight density of grasses in the upper soil layer (0–10 cm, 70%), and the higher green biomass production (~44.1 t ha–1 year–1). These beneficial changes might have further led to the lower soil bulk density (~1.05 g cm–3), higher water-filled porosity (14.7 and 16.1%), and soil organic carbon content (~0.67%) over other grasses and barren soil. Consequently, the highest total bacterial count (21.9 and 44.5 × 107 CFU g–1), soil microbial biomass carbon and enzyme activities such as acid phosphatase (17.7 and 22.6 µg p-nitrophenyl g–1 h–1) and alkaline phosphatase (9.6 and 15.9 µg p-nitrophenyl g–1 h–1) were noticed in lampagrass and guineagrass rhizospheres. Therefore, cultivation of perennial grasses in the low fertile soils of semi-arid environments can be an eco-friendly approach to enhance soil fertility, green fodder supply, and soil carbon build-up
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