A Computer Oriented Algorithm to Determine the Raw-Mixture Composition for Sintering

Sintering is an agglomeration process of fine part-icles and widely used as a standard method for preparation of blast furnace-feed. In iron-ore sintering, iron ore fines viz. iron ore crushed to ---10 mm size, classifier fines, cyclone underflow, blue-dust etc. together with other iron-bearing waste materials viz. mill-scale, flue dust etc. are mixed with fluxing materials like limestone, dolomite etc. and sintered in a continuously operated sinter strand or a bench-scale sinter pot. The sintering of fine particles results from incipient fusion of materi-als due to heat liberated by combustion of coke-breeze incorporated in the raw mixture and also exothermic heat liberated through complex chemical reactions taking place during the process of sintering. Water added during mixing helps to maintain a proper permeability and return fines act as a supporting structure for the mixture

Physical method of upgradation for low grade wolframite pre-concentrate from Degana, Rajasthan

Tungsten is a strategic metal and mostly used in defence. It is also used in cutting tools, industrial, electrical, textile and leather sectors. India's tungsten reserves are very limited and the only workable deposit is restricted to Degana in Rajasthan. Tungsten deposit occurs in association with metamorphic rocks and granite igneous rock throughout the world. At Degana, two types of deposit are being worked at, one being quartz load wherein wolframite is mineralised in quartz vein and the other is finely disseminated tungsten mineralisation in the granite body. The sample under investigation belonged to off-grade tungsten pre-concentrate - I (PC - 1) produced at Degana Plant site, assaying 14.50% WOe 20.20% SiO, and 4.13% S. The objective of this study was to find the upgradation conforming to DMRL specification i.e. final wolframite concentrate with >65.0% WO,, and S and SiO, < 1.0% each. Detailed studies indicated that grinding the feed to 200 mesh followed by sulphide flotation at 4.5 and 8.0 pH and repeated vanning of non-sulphide could produce a wanner concen¬trate assaying 64.8% WO,. 1.0% SiO, and 3.0% S with a distribution of 48.8% WO3 in it. Thorough desliming followed by sulphide flotation and then treating on vanner times could produce a concentrate analysing 68.47% WO j, 0.5% SiO3 and 0.48% S which conforms to the DMRL sped¬fications

Eco-friendly approaches to rejuvenate the Khadi udyog in Assam

346-350The handloom workers were the poorest, least respected, socially and economically deprived, living in debts and almost living like an island in the Indian society still in the 21st century. Besides, in large parts of India, handloom weaving lost its fame and prosperity. Basically, handloom weaving is a men’s domain but at this juncture, the significant contribution of women workforces cannot be over ruled. In the present study, efforts were made to make khadi fabrics more attractive with innovative designs through printing with colourants extracted from natural resources. In this article, a cost-effective and user-friendly technology for extraction of natural dyes from indigenous natural resources of northeastern part of our country has been developed. Those dye solutions is used for printing of eri silk and cotton fabrics in presence of various eco-friendly mordants in order to develop innovative designs for the markets with good colourfastness properties

Drug use in acute otitis media: a prospective study at a tertiary care teaching hospital

Background: Drug use study identifies the problems that arise from prescription and highlights the current approaches to the rational use of drugs. The objective of the study was to assess drug use pattern in patients diagnosed of acute otitis media in tertiary care teaching hospital.Methods: This prospective observational study was carried in the Otorhinolaryngology department of a tertiary care teaching hospital over a period of twelve months. The data collected for patients with acute otitis media included the patient's demographic details and the drugs prescribed. Data were analysed for drug use pattern and cost per prescription and assessment of rationality of prescription.Results: Total 153 patients were analysed, 100 (65.35%) belonged to male patients and 53 (34.65%) belonged to female patients. Children less than 2years age were the most diagnosed with AOM 47.71%, the major diagnostic symptoms were earache (58.16%) and fever (54.90%) and signs were congestion (52.94%) and discharge (43.13%). In a total 153 prescriptions (469 drugs), 33.68% were antimicrobials, followed by mineral supplements (23.67%). Average number of drugs per prescription was found to be 3.0. Most common antibiotic prescribed was amoxicillin (with or without clavulanate) in 142 (92.81%) patients. Paracetamol alone or in fixed dose combination with antihistaminics were prescribed in 131 patients. Average cost per prescription was 87.74(±35.67) Indian rupees. Seventeen (11.11%) prescriptions were rational in all the aspects based on standard guidelines.Conclusions: The present study showed that paracetamol and amoxicillin with or without clavulanate were mostly commonly prescribed in children with AOM. Irrational prescribing was seen in maximum number of cases

Gauge theory, topological strings, and S-duality

We offer a derivation of the duality between the topological U(1) gauge theory on a Calabi-Yau 3-fold and the topological A-model on the same manifold. This duality was conjectured recently by Iqbal, Nekrasov, Okounkov, and Vafa. We deduce it from the S-duality of the IIB superstring. We also argue that the mirror version of this duality relates the topological B-model on a Calabi-Yau 3-fold and a topological sector of the Type IIA Little String Theory on the same manifold.Comment: 9 pages, latex. v2: a footnote has been added. The footnote corrects an inaccuracy in the original argument; the results are unchanged. v3: exposition improve

Comparative Analysis of a Transition Region Bright Point with a Blinker and Coronal Bright Point Using Multiple EIS Emission Lines

Since their discovery twenty year ago, transition region bright points (TRBPs) have never been observed spectroscopically. Bright point properties have not been compared with similar transition region and coronal structures. In this work we have investigated three transient quiet Sun brightenings including a TRBP, a coronal BP (CBP) and a blinker. We use time-series observations of the extreme ultraviolet emission lines of a wide range of temperature T (log T = 5.3 - 6.4) from the EUV imaging spectrometer (EIS) onboard the Hinode satellite. We present the EIS temperature maps and Doppler maps, which are compared with magnetograms from the Michelson Doppler Imager (MDI) onboard the SOHO satellite. Doppler velocities of the TR BP and blinker are <,25 km s$^{-1}$, which is typical of transient TR phenomena. The Dopper velocities of the CBP were found to be < 20 km s^{-1} with exception of those measured at log T = 6.2 where a distinct bi-directional jet is observed. From an EM loci analysis we find evidence of single and double isothermal components in the TRBP and CBP, respectively. TRBP and CBP loci curves are characterized by broad distributions suggesting the existence of unresolved structure. By comparing and contrasting the physical characteristics of the events we find the BP phenomena are an indication of multi-scaled self similarity, given similarities in both their underlying magnetic field configuration and evolution in relation to EUV flux changes. In contrast, the blinker phenomena and the TRBP are sufficiently dissimilar in their observed properties as to constitute different event classes. Our work indicates that the measurement of similar characteristics across multiple event types holds class-predictive power, and is a significant step towards automated solar atmospheric multi-class classification of unresolved transient EUV sources.Comment: 38 pages, 16 figure