Beneficiation of Non-Coking Coal for Generating Low Ash Clean Coal

The rapid upsurge in India’s electricity demand with passage of time is consensual perception among energy planners and coal certainly will occupy the centre stage in driving the growth momentum of the country’s economy at macro-economic level. 80% Consumption of non-coking coal is attributable to power sector and India’s definitive coal reserves is estimated to be around 93 billion tonnes (source: Ministry of Coal), and with focussed scientific exploitation of the same, it is adept in catering to energy generation requirement of the country, spanning over next 5-6 decades. However, Indian coal has been observed to be of low quality on account of its high ash content attribute and non-coking category coal constitutes sizeable quantity of near-gravity materials (NGM), which entails beneficiation to suit end-user. The beneficiated coal has immense potential for being used as a blendable mix for metallurgical applications and such blend formulation of clean coal facilitates maximising the infusion of non-coking coal with scarce coking coal for catering to metallurgical industries, enabling lesser dependence on import of high-rank low ash content coke. The present manuscript is aimed at generating low ash (10%) clean coal from high ash (28.88%) non coking coal. The coal was characterised thoroughly in terms of petrography characteristics, size analysis, washability and chemical composition and the gross calorific value of the coal was observed to be 5327 Kcal/kg. The processing was initiated at a top size of 12.5 mm and efforts were made to achieve the objective of 10% ash level in the clean coal at the coarsest possible size adopting advanced gravity based techniques. Tactical combination of gravity separation and flotation techniques yielded clean coal (10% ash content) with maximum possible produce and results were discussed in light of experimental details

Misinformation in Online Health Communities

Spread of wrong information can be a serious deterrent to information system use especially in case of online community which typically have thousands of end users. However, literature has been weak in linking the prevalence of health misinformation on online social networks to the factors contributing to misinformation. This study seeks to reduce this gap by examining the impact of thread characteristics and user characteristics on the extent of misinformation in online social networking forum related to Parkinson\u27s disease. Our findings show that the correctness of a post is affected by clarity of the thread question, information richness and the user potential for making useful contributions

Effect of truss retention and pruning of berry on seed yield and quality of cherry tomato (Solanum lycopersicum var cerasiforme) grown under different polyhouse structures

Study was conducted to evaluate the effect of retention of truss per plant and pruning of berries per truss on seed yield and quality of cherry tomato (Solanum tycopersicum var cerasiforme L.) grown under three different polyhouse structures, viz. semi climate controlled polyhouse (P1), naturally ventilated polyhouse (P2) and insect proof nethouse (P3). Among the structures P1 gave higher berry weight (7.67 g), number of seeds/berry (60.66), 100 seed weight (0.1328 g), seed yield/berry (0.0912 g), germination (84.90%), vigour index-I (650.64), vigour index-II (1.47) and lower EC (0.0086 µS/g/cm), when compared to P2 and P3. The retention of 5 truss per plant (V1) recorded higher berry weight (7.37 g), number of seeds/berry (63.25), 100 seed weight (0.1319 g), seed yield/berry (0.0886 g), germination (84.68 %), vigour index-I (640.97), vigour index-II (1.43) and lower electrical conductivity (0.0083 µS/ g/cm), as compared to V2 and V3. The thinning of berry, i.e 10 per truss (B1) has given significantly higher mean berry weight (8.21 g), number of seeds/berry (61.53), 100 seed weight (0.1323 g), 100 seed weight (0.1323 g), seed yield/berry (0.0913 g), germination (86.01%), vigour index-I (651.96), vigour-II (1.46) and lower EC (0.0080 µS/g/ cm) in comparison to B2 and B3

A study of minimally invasive percutaneous plate osteosynthesis for tibial plateau fractures

Background: Fractures of proximal tibia involve a major weight-bearing joint and are serious injuries, which, if not treated well, result in functional impairment. To preserve normal knee function one must strive to maintain joint congruity, preserve the normal mechanical axis, ensure joint stability and restore a full range of motion. This is a formidable task to accomplish, especially in the face of associated medical conditions of the patients.Methods: In our study, 30 cases were selected. Selection of cases were done on the basis of X-rays. Schatzker type I, II, III, IV, V & VI included in study. Criteria for acceptable reduction 1) <5 mm of articular step; 2) <5 mm of articular depression. Each case is referred to one set of tibial plateau fracture, showing distribution of tibia plateau fractures that we treated with MIPPO. Clinical follow-up examination was performed at 4, 6, 10, 12 weeks and 3, 6 months. Clinico-radiological assessment was done at 3 month and grading was done. Patients were evaluated according to grading minimum 3 months after injury.Results: Our study of 30 tibial plateau fractures confirms that the MIPPO technique is an excellent treatment modality in case of tibial plateau fractures. We observed these fractures mainly in age group of 30-40 years, which were involved in road traffic accident. Tibial plateau fractures seen in elder age group were mainly due to abnormal loading patterns on the leg. We have found oblique views very much informative especially for posterolateral or posteromedial displacement, articular depression which helps to plan the position and direction of screws to be used for fixation. Conclusions: In view of the excellent results obtained with this technique, we advocate MIPPO over conventional open reduction and internal fixation technique for tibial plateau fracture fixation

Development of Processing Technology for Beneficiation of Lean Iron Ore Fines from GOA

Because of the fast depletion of high grade iron ores and increased industrial demand, low grade iron ores which have hither to been unused, have become a focus of interest in recent years. Thus, the objective of the present study is to beneficiate lean iron ore fines from Goa for utilization in metallurgical plants. The feed sample assayed 44.25% Fe, 29.42% silica and 2.81% alumina. It is apparent from the petrographic observations that the primary ore consisted mostly of magnetite with goethite and quartz; both mineral occurring in granular form and in alternate bands. It was observed from the liberation data that reasonable degree of liberation is achieved only below 210 micron size. Several beneficiation techniques such as scrubbing, jigging, spiralling, hydrocycloning, and magnetic separation are being employed to develop a suitable process flowsheet as a step to enhance the quality of the iron ore and to reduce the gangue content. The developed process flowsheet gives the desired enrichment of the lean iron ore fines to a grade suitable for sinter feed and pellet feed at reasonable yield and discussed in the light of our experimental results

Nanoscale Heterogeneity of Multilayered Si Anodes with Embedded Nanoparticle Scaffolds for Li-Ion Batteries

A new approach on the synthesis of Si anodes for Li‐ion batteries is reported, combining advantages of both nanoparticulated and continuous Si films. A multilayered configuration prototype is proposed, comprising amorphous Si arranged in nanostructured, mechanically heterogeneous films, interspersed with Ta nanoparticle scaffolds. Particular structural features such as increased surface roughness, nanogranularity, and porosity are dictated by the nanoparticle scaffolds, boosting the lithiation process due to fast Li diffusion and low electrode polarization. Consequently, a remarkable charge/discharge speed is reached with the proposed anode, in the order of minutes (1200 mAh g−1 at 10 C). Moreover, nanomechanical heterogeneity self‐limits the capacity at intermediate charge/discharge rates; as a consequence, exceptional cycleability is observed at 0.5 C, with 100% retention over 200 cycles with 700 mAh g−1. Higher capacity can be obtained when the first cycles are performed at 0.2 C, due to the formation of microislands, which facilitate the swelling of the active Si. This study indicates a method to tune the mechanical, morphological, and electrochemical properties of Si electrodes via engineering nanoparticle scaffolds, paving the way for a novel design of nanostructured Si electrodes for high‐performance energy storage devices

Inoculation of silicon nanoparticles with silver atoms

Peer reviewe

Tuning the onset of ferromagnetism in heterogeneous bimetallic nanoparticles by gas phase doping

In the nanoregime, chemical species can reorganize in ways not predicted by their equilibrium bulk behavior. Here, we engineer Ni-Cr nanoalloys at the magnetic end of their compositional range (i.e., 0–15 at. % Cr), and we investigate the effect of Cr incorporation on their structural stability and resultant magnetic ordering. To ensure their stoichiometric compositions, the nanoalloys are grown by cluster beam deposition, a method that allows one-step, chemical-free fabrication of bimetallic nanoparticles. While full Cr segregation toward nanoparticle surfaces is thermodynamically expected for low Cr concentrations, metastability occurs as the Cr dopant level increases in the form of residual Cr in the core region, yielding desirable magnetic properties in a compensatory manner. Using nudged elastic band calculations, residual Cr in the core is explained based on modifications in the local environment of individual Cr atoms. The resultant competition between ferromagnetic and antiferromagnetic ordering gives rise to a wide assortment of interesting phenomena, such as a cluster-glass ground state at very low temperatures and an increase in Curie temperature values. We emphasize the importance of obtaining the commonly elusive magnetic nanophase diagram for M-Cr (M=Fe, Co, and Ni) nanoalloys, and we propose an efficient single-parameter method of tuning the Curie temperature for various technological applications.Peer reviewe

Gas-Phase Synthesis of Trimetallic Nanoparticles

To this day, engineering nanoalloys beyond bimetallic compositions has scarcely been within the scope of physical deposition methods due to the complex, nonequilibrium processes they entail. Here, we report a gas-phase synthesis strategy for the growth of multimetallic nanoparticles: magnetron-sputtering inert-gas condensation from neighboring monoelemental targets provides the necessary compositional flexibility, whereas in-depth atomistic computer simulations elucidate the fast kinetics of nucleation and growth that determines the resultant structures. We fabricated consistently trimetallic Au–Pt–Pd nanoparticles, a system of major importance for heterogeneous catalysis applications. Using high-resolution transmission electron microscopy, we established their physical and chemical ordering: Au/Pt-rich core@Pd-shell atomic arrangements were identified for particles containing substantial amounts of all elements. Decomposing the growth process into basic steps by molecular dynamics simulations, we identified a fundamental difference between Au/Pt and Pd growth dynamics: Au/Pt electronic arrangements favor the formation of dimer nuclei instead of larger-size clusters, thus significantly slowing down their growth rate. Consequently, larger Pd particles formed considerably faster and incorporated small Au and Pt clusters by means of in-flight decoration and coalescence. A broad range of icosahedral, truncated-octahedral, and spheroidal face-centered cubic trimetallic nanoparticles were reproduced in simulations, in good agreement with experimental particles. Comparing them with their expected equilibrium structures obtained by Monte Carlo simulations, we identified the particles as metastable, due to out-of-equilibrium growth conditions. We aspire that our in-depth study will constitute a significant advance toward establishing gas-phase aggregation as a standard method for the fabrication of complex nanoparticles by design.Peer reviewe

Aggregation vs Surface Segregation: Antagonism over the Magnetic Behavior of NiCr Nanoparticles

Annealing is a valuable method for fine-tuning the ultrasmall magnetic properties of alloy nanoparticles (NPs) by controlling their sizes, modifying their surfaces, and affecting their magnetic interactions. Herein, we study the effect of moderate annealing (450°C) on strongly interacting NiCr nanoparticle assemblies (0 <= atom % Cr ≤ 15) immediately after deposition. Concurrent temperature-dependent electron microscopy and magnetization data demonstrate the interplay of two competing factors, namely, enhanced particle aggregation and element-specific surface segregation, on the magnetic properties, with the former boosting and the latter suppressing them. Strong interparticle interactions can lead to a magnetic response different from that of superparamagnetic particles, namely, from canonical spin-glass (0 atom % Cr) to correlated spin-glass (5-15 atom % Cr) behavior below higher spin-glass transition temperatures T-g (20-350 K). The observation of "high-field susceptibility" below cryogenic temperatures (≤20 K) is ascribed to the presence of inhomogeneity/defects caused by Cr segregation. This work emphasizes the necessity of taking into account the delicate balance of such competing factors to understand the magnetic properties of nanoparticulate samples