Potentials of airborne hyperspectral aviris-ng data in the exploration of base metal deposit—a study in the parts of Bhilwara, Rajasthan

In this study, we have processed the spectral bands of airborne hyperspectral data of Advanced Visible Infrared Imaging Spectrometer-Next Generation (AVIRIS-NG) data for delineating the surface signatures associated with the base metal mineralization in the Pur-Banera area in the Bhilwara district, Rajasthan, India.The primaryhost rocks of the Cu, Pb, Zn mineralization in the area are Banded Magnetite Quartzite (BMQ), unclassified calcareous silicates, and quartzite. We used ratio images derived from the scale and root mean squares (RMS) error imagesusing the multi-range spectral feature fitting (MRSFF) methodto delineate host rocks from the AVIRIS-NG image. The False Color Composites (FCCs) of different relative band depth images, derived from AVIRIS-NG spectral bands, were also used for delineating few minerals. These minerals areeither associated with the surface alteration resulting from the ore-bearing fluid migration orassociated with the redox-controlled supergene enrichments of the ore deposit.The results show that the AVIRIS-NG image products derived in this study can delineate surface signatures of mineralization in 1:10000 to 1:15000 scales to narrow down the targets for detailed exploration.This study alsoidentified the possible structural control over the knownsurface distribution of alteration and lithocap minerals of base metal mineralizationusing the ground-based residual magnetic anomaly map. This observationstrengthens the importance of the identified surface proxiesas an indicator of mineralization. X-ray fluorescence analysis of samples collectedfromselected locations within the study area confirms the Cu-Pb-Zn enrichment. The sulfide minerals were also identified in the microphotographs of polished sections of rock samples collected from the places where surface proxies of mineralization were observed in the field. This study justified the investigation to uti-lize surface signatures of mineralization identified using AVIRIS-NG dataand validated using field observations, geophysical, geochemical, and petrographical data

Switching of ferroelectric liquid crystal doped with cetyltrimethylammonium bromide-assisted CdS nanostructures

Large scale high yield cadmium sulfide (CdS) nanowires with uniform diameter were synthesized using a rapid and simple solvo-chemical and hydrothermal route assisted by the surfactant cetyltrimethylammonium bromide (CTAB). Unique CdS nanowires of different morphologies could be selectively produced by only varying the concentration of CTAB in the reaction system with cadmium acetate, sulfur powder and ethylenediamine. We obtained CdS nanowires with diameters of 64–65 nm and lengths of up to several micrometers. A comparative study of the optical properties of ferroelectric liquid crystal (FLC) Felix-017/100 doped with 1% of CdS nanowires was performed. Response times of the order of from 160 to 180 μs, rotational viscosities of the order of from 5000 to 3000 mN s m−2 and polarizations of the order of from 10 to 70 nC cm−2 were measured. We also observed an anti-ferroelectric to ferroelectric transition for CdS doped FLC instead of the ferroelectric to paraelectric transition for pure FLC

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

The use of specific energy in rotary drilling : the effect of operational parameters

In rotary drilling, specific energy is considered to be an important parameter for defining mechanical efficiency of the rock destruction process. Specific Energy is defined as the energy required to remove one unit of rock. Specific energy is the function of the size of the borehole and various operational parameters including feed force, rotation speed, rotation torque and penetration rate. The harder the material, the higher the specific energy. The traditional method to calculate the specific energy is based on the parameters penetration rate, feed force, torque and rotation speed, that can be provided by Measurement While Drilling (MWD) data from the drill process. In this study, MWD data from an open pit mine in Sweden are used to evaluate data trends among logged parameters and calculated average specific energy. The results show that there is a significant hole length dependency for penetration rate and feed force that affects the predicted specific energy. This may be explained by that the hole cleaning efficiency is reduced with increasing hole length. The analysis shows that the specific energy is over-estimated by 45% in the bottom of an 18 m hole compared to the collaring point. The suggested solution is to use hole average or complement the specific energy calculation with a hole length related component.Keywords: Specific energy, Measurement While Drilling (MWD), Rotary drilling, Geo-mechanical response, Rock-destruction processGodkänd; 2015; 20150107 (rajgho

Intraoperative hydrostatic reduction of intussusception

Aims: To find out an easier way of reduction of intussusception during open surgery to avoid unnecessary bowel injury. Materials and Methods: Under general anesthesia, before laparotomy, warm normal saline was infused into the rectum with a Foley catheter and an intravenous drip set maintaining the level of the bottle at 80 cm above the operating table. After opening the abdomen, pressure was applied on the colon filled with normal saline distal to the intussusceptum. The pressure was transmitted to the intussusceptum and the walls of the intussuscipient and caused reduction of intussusception without any injury to the intussuscipient and intussusceptum. This procedure was performed on those patients on whom laparotomy was performed as a primary procedure due to nonavailability of fluoroscopy or ultrasonography. Results: Between August 1998 and July 2005, we had six patients of mean (range) age 11 months (7-17 months). In two cases, at laparotomy, the intussusceptions were found to have already reduced. Conclusions: Gentle finger pressure is necessary for reduction of intussusception. This subjective "gentleness" is dependant on experience of the surgeon and varies from person to person. Focal pressure on the intussuscipient and apex of the intussusceptum by the finger during reduction may be more damaging than the diffusely transmitted hydrostatic pressure even by a less-experienced surgeon. This will avoid the needless resection and anastomosis of the intestine on many occasions

Facile synthesis of BSCF perovskite oxide as an efficient bifunctional oxygen electrocatalyst

We present a facile way to synthesize BSCF by using glycine-nitrate auto-combustion followed by annealing at different conditions, which work as high-performance bifunctional electrocatalyst for oxygen evolution (OER) as well as oxygen reduction (ORR) reactions in alkaline solution with comparatively better efficiency for OER. Annealing condition plays an important role towards catalytic performance due to morphological control and surface composition. Although, there is no significant change in onset potentials but these catalysts afford a current density >10 mA cm(-2) at the potential of 1.65 V for oxygen evolution reaction and a current density >2.5 mA cm(-2) at the potential of 0.009 V for oxygen reduction reaction with respect to RHE in 0.1 M KOH. The underlying mechanism for ORR and OER as well as catalytic activity differences were understood with the help of different analytical characterization techniques. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved

Study of the Capacitive Behavior of MOF-Derived Nanocarbon Polyhedra

Co containing zeolitic imidazolate framework (ZIF-67) with polyhedral morphology was synthesized in aqueous media and utilized as precurser for synthesis of nanoporous carbon polyhedra without using any other carbon source. The phase, composition and morphology of the annealed products could be tailored by changing the annealing temperature as well as acid treatment. Our study herein provides a new insight into the formation of porous carbon polyhedra from ZIF-67