An Innovative Magnetic Charging Chute to Improve Productivity of Sinter Machine at Rourkela Steel Plant

AbstractSintering is a process in sinter machine for agglomeration of iron ore and other raw material fines into a compact porous mass, i.e., sinter, used in Blast Furnaces as an iron bearing input charge material for hot metal production. ‘Permeability’ of sinter-bed on sinter machine i.e., the porosity in sinter-bed of charged materials, facilitates atmospheric air passes from the top to bottom across the depth of sinter-bed, when suction created from the bottom of the bed, for efficient heat carry over from top to bottom of the bed for complete burning of charged materials for effective sintering process controls the productivity of the sinter machine. The level of ‘permeability’ in sinter-bed is depending upon the effectiveness of ‘charging chute’ in size-wise ‘segregation’ of charge materials across the depth in sinter-bed, achieved due to differences in the sliding velocities of particles during charging into the moving sinter-bed. The permeability achieved by the earlier conventional ‘charging chute’ was limited due to its design and positional constraints in sinter machine. Improving the productivity of sinter machine, through increased permeability of sinter bed is successfully achieved through implementation of an innovatively designed and developed, “Magnetic Charging Chute” at Sinter Plant no. 2 of Rourkela Steel Plant. The induced magnetic force on the charged materials while the charge materials dropping down through the charge chute has improved the permeability of sinter bed through an unique method of segregating the para-magnetic materials and the finer materials of the charge materials to top layer of sinter bed along with improved size-wise segregation of charge materials. This has increased the productivity of the sinter machine by 3% and also reduced the solid fuel consumption i.e., coke breeze in input charge materials by 1kg/t of sinter

QSAR STUDIES, AND IN SILICO ADME PREDICTION OF P-AMINOSALICYLIC ACID DERIVATIVES AS NEURAMINIDASE INHIBITORS

QSAR analysis on a set of  synthesized p-Aminosalysilic Acid derivatives analogues tested growth inhibitory antiviral activity was performed by using MLR procedure. The activity contribution of these compounds were determined from regression equation and the validation procedures to analyze the predictive ability of QSAR models were described.The results are discussed on the basis of statistical data. High agreement between experimental  and predicted antiviral activity inhibitory values are obtained. The results revealed the significant roles of topological, geometrical and substituent electronic descriptor parameters on the inhibitory activitypIc50 of coumarin derivative analogues of the studied moleculesKey Words: QSAR, Antiviral Activity, ML

Skin Sympathetic Nerve Activity as a Biomarker for Syncopal Episodes during a Tilt Table Test

Background: Autonomic imbalance is the proposed mechanism of syncope during a tilt table test (TTT). We have recently demonstrated that skin sympathetic nerve activity (SKNA) can be noninvasively recorded using electrocardiographic electrodes. Objective: The purpose of this study was to test the hypothesis that increased SKNA activation precedes tilt-induced syncope. Methods: We studied 50 patients with a history of neurocardiogenic syncope undergoing a TTT. The recorded signals were band-pass filtered at 500-1000 Hz to analyze nerve activity. Results: The average SKNA (aSKNA) value at baseline was 1.38 ± 0.38 μV in patients without syncope and 1.42 ± 0.52 μV in patients with syncope (P = .77). On upright tilt, aSKNA was 1.34 ± 0.40 μV in patients who did not have syncope and 1.39 ± 0.43 μV in patients who had syncope (P = .65). In all 14 patients with syncope, there was a surge of SKNA before an initial increase in heart rate followed by bradycardia, hypotension, and syncope. The peak aSKNA immediately (<1 minute) before syncope was significantly higher than baseline aSKNA (2.63 ± 1.22 vs 1.39 ± 0.43 μV; P = .0005). After syncope, patients were immediately placed in the supine position and aSKNA dropped significantly to 1.26 ± 0.43 μV; (P = .0004). The heart rate variability during the TTT shows a significant increase in parasympathetic tone during syncope (low-frequency/high-frequency ratio: 7.15 vs 2.21; P = .04). Conclusion: Patients with syncope do not have elevated sympathetic tone at baseline or during the TTT except immediately before syncope when there is a transient surge of SKNA followed by sympathetic withdrawal along with parasympathetic surge

Fragmented Left Sided QRS in Absence of Bundle Branch Block: Sign of Left Ventricular Aneurysm

Background: A left ventricular aneurysm (LVA) occurs between 3.5% and 9.4% of all cases of acute myocardial infarction. A fragmented left sided QRS (RSR` pattern or its variant RSr`, rSR`, or rSr`) without evidence of bundle branch block (QRS duration ≤120 ms) on the ECG may be associated with a significant myocardial scar, which is the characteristic of a LVA. We, therefore, postulate that fragmented QRS (RSR` pattern or its variant) in the left sided leads (I, aVL, V3 to V6) may be a useful sign of LVA. Methods: ECGs of 110 consecutive patients with LVA documented by left ventricular angiography (30° right anterior oblique view) was compared with 220 patients without LVA (110 patients with and 110 patients without coronary artery disease (CAD)), who were evaluated for CAD by symptoms and signs. Results: The sensitivity of the fragmented QRS for identification of LVA was 50% (55 of 110 patients) and specificity was 94.6% (209 of 220). Within the study population, the positive predictive value of the fragmented QRS for LVA was 83.3% (55 of 66) and the negative predictive value was 79.2% (209 of 264). Based on the range of prevalence of LVA in postmyocardial infarction population (3.5–9.4%) and on observed sensitivity and specificity, the positive predictive value of fragmented QRS for LVA after infarction can be estimated at 29–53% and the negative predictive value can be estimated at 95–98%. Conclusion: The sensitivity of fragmented QRS in left precordial leads for LVA was only 50%, whereas the specificity was 94.5%. It has a relatively low to moderate positive predictive value and high negative predictive value

Reduction of 2-H-substituted pyrrolinium cations: the carbon-carbon single bond in air stable 2,2′-bipyrrolidines as a two-electron-source

Reduction of 2-H-substituted pyrrolinium cations via initially formed secondary radicals results in either dimerisation or H-abstracted products, while the outcome depends on the N-substituents. The resultant central carbon-carbon single bond in the dimerised 2,2′-bipyrrolidine derivatives can be oxidised chemically and electrochemically. The notably air and moisture-stable dimers were subsequently utilised as a source of two electrons in various chemical transformations

Mechanisms of sinoatrial node dysfunction in a canine model of pacing-induced atrial fibrillation

BACKGROUND The mechanism of sinoatrial node (SAN) dysfunction in atrial fibrillation (AF) is unclear. OBJECTIVE The purpose of this study was to test the hypothesis that defective spontaneous sarcoplasmic reticulum (SR) Ca(2+) release (Ca(2+) clock) is in part responsible for SAN dysfunction in AF. METHODS Arrhythmic events and SAN function were evaluated in pacing-induced AF dogs (n = 7) and in normal dogs (n = 19) with simultaneous intracellular calcium (Cai) and membrane potential recording. RESULTS AF dogs had frequent sinus pauses during Holter monitoring. Isolated right atrium (RA) from AF dogs showed slower heart rate (P = .001), longer SAN recovery time (P = .001), and longer sinoatrial conduction time (P = .003) than normal. In normal RAs, isoproterenol 0.3 and 1 mu mol/L increased heart rate by 96% and 105%, respectively. In contrast, in RAs from AF dogs, isoproterenol increased heart rate by only 60% and 72%, respectively. Isoproterenol induced late diastolic Cai elevation (LDCAE) at superior SAN in all 19 normal RAs but in only 3 of 7 AF RAs (P = .002). In AF RAs without LDCAE (n = 4), heart rate increased by the acceleration of ectopic foci. Caffeine (20 mmol/L) injection increased heart rate with LDCAE in all 6 normal RAs but did not result in LDCAE in any of the 5 AF RAs (P = .002). Type 2 ryanodine receptor (RyR2) in the superior SAN of AF dogs was decreased to 33% of normal (P = .02). CONCLUSION SAN dysfunction in AF is associated with Ca(2+) clock malfunction, characterized by unresponsiveness to isoproterenol and caffeine and down-regulation of RyR2 in SAN