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The conversion of coal to a hydrophilic state presents a significant challenge for process engineers, especially when treating oxidized coals in flotation-based beneficiation plants. Flotation of oxidized coal often requires a substantial consumption of oily collectors, resulting in unacceptably low yields. To address this, several pre-processing methods have emerged for coal deoxidation, including mild grinding, surface activation, and ultrasonic or microwave treatment. However, their effective application depends on a thorough understanding of the degree of oxidation in the coals. Therefore, it is crucial to gain insights into the nature of oxidized coal before initiating the deoxidation process. This present study provides various characterization techniques such as XRD, SEM-EDS, FTIR Spectroscopy, Raman Spectroscopy, TGA, and Zeta Potential Analysis employed on oxidized low-grade coals. The study revealed that the proximate analysis of low-grade coals KC, DC, RC, and PC contains varying ash percentages of 32.65%, 44.47%, 25.44%, and 37.53%, respectively, with SiO2 and Al2O3 comprising over 80% of the total ash. XRD characterizations identified quartz and kaolinite as major mineral phases in all samples, while SEM-EDS confirmed rough coal surfaces with peeling, off-white aggregations, and surface pores. HGI value ranging from 80 to 91 was attributed to partial decomposition and surface cracking due to oxidation. FTIR spectra revealed pronounced oxidation behavior, with strong −OH peaks in the 3600–3700 cm−1 range. Zeta potential analysis affirmed the oxidized nature of the coals with a pH below 3.1 and an extremely negative zeta potential beyond 3.1. The findings mentioned above showcase the distinct characteristics of oxidized low-grade coals, which serve as crucial indicators for exploring coal beneficiation, especially through the flotation process. [ABSTRACT FROM AUTHOR]

The co-gasification of high moisture and high volatile content low-rank lignite (LG) coal and a common waste generated from the brewed tea leaves was studied in a fluidized bed gasification unit. Multiple experiments were conducted at different temperatures, ranging from 800 °C to 900 °C, at fixed operating parameters to elucidate the catalytic thermo-chemical impact on the gasifier performance parameters. The catalytic effect of alkali and alkaline earth metals (AAEMs), especially CaO, K 2 O, and Na 2 O present in the spent tea waste (STW) sample, on the product gas composition and performance parameters during the co-gasification experiments with LG was demonstrated. Mixed blends of LG and STW showed enhancement in the overall reactivity of the steam gasification runs, compared to the LG-only feed, primarily due to the change in the surface morphology, textures, and pore structures of the solid product ash samples, as identified with the electron spectroscopy analysis. Liquid and product samples were analyzed using characterization techniques such as Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX) analytical techniques, along with the proximate, ultimate, and X-ray fluorescence (XRF) analysis of the gasification feed samples. An optimized blend ratio of 20 wt % of STW with LG sample enhanced the volumetric gas composition of H 2 and CH 4 gases from 52.03 % to 61.32 % and 3.98 %–5.45 % (on a dry-N 2 -free basis) with a relatively constant CO gas composition. It showed a reduced CO 2 composition from 28.64 % to 18.25 % (on a dry-N 2 -free basis) for the gasification temperature of 900 °C. Even at the lower gasification temperatures of 800 °C and 850 °C with LG + STW feed, steam gasification experiments showed relatively comparable or superior performance to gasification experiments at 900 °C with LG-only feed. The present study indicated a holistic way to utilize the spent tea waste generated from millions of homes and commercial establishments in various parts of the world with potential application towards synergistic gasification process with other conventional carbon-source materials. [Display omitted] • A novel study of co-gasification of lignite and spent tea waste. • Significantly enhanced hydrogen production with high CGE and CCE by adding STW to lignite. • Synergistic effect of alkali and alkaline earth metals (AAEMs) of STW on gasification performance. • Detailed feed and product characterization studies using XRF, TGA, FTIR, XRD, SEM, etc. • Holistic and sustainable utilization of millions of tonnes of STW generated worldwide. [ABSTRACT FROM AUTHOR]

[Display omitted] • A detailed mineralogical characterization study. • A feasibility study for the potential utilization of coal gasification ash. • First time study of a coal gasification waste generated from an Indian plant. • Optical and stereomicroscopy, FESEM with EDS, XRF, SEM-EDX, XRD, and TGA applied. This work aims to perform the applied mineralogical characterization of coal gasification ash (CGA) generated from a commercial fixed bed downdraft gasification plant in eastern India. Analytical and characterization techniques such as stereomicroscopy, optical microscopy, field emission scanning electron microscopy (FESEM) with energy dispersive spectroscopy (EDS) attached, X-ray fluorescence (XRF), energy dispersive x-ray spectrometer associated scanning electron microscope (SEM-EDX), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were applied for analyzing the coal and the corresponding gasification ash sample. These analytical techniques illustrate that SiO 2 and Al 2 O 3 are the major gasification ash phases, accounting for almost 85% of the entire CGA composition. The dominant mineral phases, such as quartz, mullite, and other aluminosilicates, provide an opportunity for utilization in construction and refractory material manufacturing. Moreover, confirming the presence of rare and valuable earth elements (RVEEs) in the CGA sample with SEM-EDX analysis unearths a new application window in meeting the requirement of the RVEEs starved nation like India, where very few commercial-scale coal gasification units are operational. [ABSTRACT FROM AUTHOR]

[Display omitted] • Feasible, cost-effective and green approach for synthesis of NiO@WO 3 -Chitosan nanocomposite. • High photodegradation of Tropaeolin OOO (96%) and Eriochrome black T (92%) by NiO@WO 3 -Chitosan. • Degradation of pollutants followed first order kinetics under daylight. • Smaller non-toxic by-products and high reusability (8th cycle) confirm high efficiency. Azo dyes such as Tropaeolin OOO (TOOO) and Eriochrome black T (EBT) are used in various industrial and laboratory applications. However, their recalcitrant properties make them toxic chemicals and require efficient removal-strategy based on polymer decorated semiconductor nanocomposite. Herein, photodegradation of TOOO and EBT in water was investigated at different reaction parameters through NiO@WO 3 -chitosan synthesized by green procedure using A. indica. PXRD spectra peaks show semi-crystalline behaviour with spherical morphology and chitosan around metal oxide. In FT-IR, New spectral peaks observed at 1023 cm−1, 870 cm−1, and 540 cm−1 vibration indicated between Ni-O-W, Ni-N, and W-N confirmed effecting coupling. Both dyes (10 mg/L) were found completely colourless within 3 h under sunlight with pH of 7 at 20 mg of catalyst load. Difference in max degradation of 96 % and 92 %, respectively to TOOO and EBT dye credit to structure difference. 1st-order reaction kinetics following early Langmuir adsorption and degradation at optimum condition rate constant k (0.26–0.19-min−1) and half time t 1/2 (2.68––3.64 min−1). Efficiency of NiO@WO 3 -chitosan was maintained due to its fine morphology with elevated surface-area (75 m2g−1), large negative zeta potential (−29.5 mV), and lesser value of band distance (2.1 eV). Involvement of •OH, O 2 –• and holes in photocatalysis mechanism to break complex molecules of TOOO and EBT was revealed in Scavenger analysis. After degradation, small-safer metabolites were confirmed by LC-MS. Reusability up to 8th cycle of NiO@WO 3 -chitosan without photoactivity reduction makes it a cost-effective cum sustainable composite for industries and wastewater pollutants removal with good surface properties. [ABSTRACT FROM AUTHOR]

It is well known that environmental decoherence is a crucial barrier in realizing various quantum information processing tasks; on the other hand, it plays a pivotal role in explaining how a quantum system's fragile state leads to a robust classical state. Zurek (Nat Phys 5(3):181–188, 2009) was the first to develop the theory which successfully describes the emergence of classical objectivity of quantum systems using decoherence, introduced by the environment. Here, we consider an n-qubit generalized quantum circuit for the quantum system–environment interaction model, where the first qubit represents the quantum system, and the rest are for the environmental fragments. This quantum circuit is implemented on ibmq_athens and ibmq_16_melbourne for n = 2 , 3 , 4 , 5 , 6 . Its accuracy is checked using quantum state tomography and enhanced using the quantum error mitigation procedure. The reconstructed density matrices are used to investigate quantum-classical correlation and the mutual information between the quantum system and the environment. The investigation proves the quantum Darwinism principle when the quantum circuits are executed on the noise-less simulator; however, it shows the unaccountable behavior when implemented on the real quantum devices. The results via the noise-less simulator successfully prove that the environmental fragment size and the interaction strength play a crucial role in the emergence of classicality. [ABSTRACT FROM AUTHOR]

Steam gasification experiments were conducted with coal and petcoke in conjunction with potentially renewable biomass substances, namely coconut shell, coconut husk, and banana peduncle, which are usually considered waste materials. The gasification performance in a bench-scale externally heated fluidized bed gasifier was evaluated based on the product syngas quality and the detailed characterization of feed and product samples using X-ray fluorescence (XRF), thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy analysis. This work performed experiments at relatively constant operating parameters: solid feed rate, steam/O 2 ratio, feed particle size, and gasification reactor temperature. Biomass waste resources showed an augmentation in the syngas product quality for both the coal and petcoke samples, especially in cold gas efficiency (CGE) and carbon conversion efficiency (CCE). A maximum increase in CCE from 44.3 % to 72 % for the coal sample and from 19.3 % to 36.0 % for the petcoke sample was witnessed, whereas for the CGE, a rise of 35.8 %–91.7 % for the coal and 44.3 %–59.8 % for the petcoke with 80/20 blended biomass waste samples, was observed compared to the coal and petcoke only samples. The maximum hydrogen product gas yield between 53 and 73.7 vol % and combustible gas yields between 62.2 and 86.7 vol % were obtained on a nitrogen gas-free basis during the experiments. The solid residues of different gasification experiments were characterized and analyzed by scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX) and field emission-scanning electron microscopy (FE-SEM) analytical techniques to elucidate the high yield of energy-intensive gases. FTIR analysis was performed on all the liquid product samples obtained during the gasification experiments. The presence of alkali and alkaline earth metals (AAEMs) in biomass wastes highlighted the catalytic effect of these elements during the gasification experiments. The current work provides an opportunity to reduce carbon footprints with effective and efficient utilization of conventional energy feedstocks in conjunction with other waste substrates. [Display omitted] • A novel study of co-gasification of coal, petcoke with coconut, banana wastes. • High CGE, CCE, and combustible product gas yield due to the synergistic effect. • Catalytic effect of alkali and alkaline earth metals (AAEMs) of biomass wastes. • Analysis of feed samples applying proximate, ultimate, XRF, TGA, XRD, FTIR, etc. • FTIR, FE-SEM, and SEM-EDX-based gasification solid feed and product analysis. [ABSTRACT FROM AUTHOR]

Autosomal dominant polycystic kidney disease (ADPKD) is an inherited chronic kidney disorder (CKD) that is characterized by the development of numerous fluid-filled cysts in kidneys. It is caused either due to the mutations in the PKD1 or PKD2 gene that encodes polycystin-1 and polycystin-2, respectively. This condition progresses into end-stage renal disorder if the renal or extra-renal clinical manifestations remain untreated. Several clinical trials with a variety of drugs have failed, and the only Food and Drugs Administration (FDA) approved drug to treat ADPKD to date is tolvaptan that works by antagonizing the vasopressin-2 receptor (V2R). The pathology of ADPKD is complex and involves the malfunction of different signaling pathways like cAMP, Hedgehog, and MAPK/ERK pathway owing to the mutated product that is polycystin-1 or 2. A measured yet substantial number of preclinical studies have found pioglitazone to decrease the cystic burden and improve the renal function in ADPKD. The peroxisome proliferator-activated receptor-gamma is found on the epithelial cells of renal collecting tubule and when it gets agonized by pioglitazone, confers efficacy in ADPKD treatment through multiple mechanisms. There is only one clinical trial (ongoing) wherein it is being assessed for its benefits and risk in patients with ADPKD, and is expected to get approval from the regulatory body owing to its promising therapeutic effects. This article would encompass the updated information on the epidemiology, pathophysiology of ADPKD, different mechanisms of action of pioglitazone in the treatment of ADPKD with preclinical and clinical shreds of evidence, and related safety updates. [ABSTRACT FROM AUTHOR]

In this work, graphene coated optical fiber structure has been exploited theoretically for refractive index sensing within visible operating region. A high refractive index polymer layer is also considered as a matching layer between graphene and the fiber core to generate lossy mode resonances in the desired spectrum. It is observed that multilayer graphene coating supports much sharper and narrower resonances than the graphene monolayer. Sensing characteristics with variation in number of graphene layers and polymer layer thickness are investigated with different polarizations of light. Calibration curves indicating change in resonant wavelength corresponding to the refractive index variation of sensing medium are also presented. It is observed that polymer layer act as the catalyst in enabling the structure to support resonances and shifting the operating region in visible spectrum. A maximum sensitivity of 300 nm/RIU for RI range of 1.33–1.40 is reported for p-polarization of light. It is believed that visible range operation of the proposed structure will make it cost effective and highly suitable for the development of bio-chemical sensors. • Graphene coated optical fiber structure has been exploited theoretically for refractive index sensing within visible range of operation. • A high index polymer matching layer, n p = 1.75 is used between the Graphene layer and unclad core of fiber to support Lossy mode resonance within visible spectrum. • Various sensing parameters are analyzed to achieve high sensitivity with narrow FWHM. • Due to visible operating region, it is believed that the proposed structure will be suitable for cost-effective biochemical sensing applications. [ABSTRACT FROM AUTHOR]

Thiram (tetramethyl thiuram disulfide) is a fungicide and is used for crop protection. It has several health-related issues when we consume this for a long period. Food and drug administration (FDA) warns higher than 30 μ M (7 ppm) limit. Hence, the monitoring of the Thiram pesticide in foods and vegetables is of utmost importance. Conventional techniques such as GC–MS, HPLC and LC-MS available for quantification of pesticides are very costly, time-consuming and require sophisticated laboratory with highly skilled manpower. This work aims to design and develop an efficient label-free SERS (Surface Enhanced Raman Spectroscopy) active substrate which can detect a very low-level concentration of pesticides with low cost and simple process. SERS is a surface-sensitive technique that provides the enhanced form of Raman signals. Gold nanoparticles are used for SERS-active substrate preparation which has been synthesized by the chemical reduction method. Thiram pesticide with concentration as low as 1 nM is detected with the SERS substrate developed in this work. This makes rapid and on-site detection of pesticides feasible in future. [Display omitted] • The work presents a flexible SERS-active substrate for pesticide detection. • AuNPs are synthesized, and the SERS substrate is prepared using paper. • FESEM and UV–Vis spectroscopy are used for the AuNPs characterization. • Presented work demonstrates the detection of Thiram in low concentrations. [ABSTRACT FROM AUTHOR]

Surface enhanced Raman spectroscopy or surface enhanced Raman scattering (SERS) being a very powerful technique for quantitative and qualitative analysis finds application in low concentration detection of chemical and biological samples. In this work, we have presented a complete methodology of simulating nanoparticles-based SERS substrate. Different configurations namely single nanoparticle, dimer, trimer and tetramer nanoparticle clusters are simulated and enhancement factor for each configuration is estimated. Presented simulations are carried out with COMSOL Multiphysics software using Electromagnetic Waves module (Wave Optics) in frequency domain. The model of gold nanoparticle is established to determine the scatter field, which was further used to estimate the enhancement factor. Simulation results thus obtained are then validated with experimental results. The simulation study using the COMSOL Multiphysics tool helps in the design and development of the SERS substrate for maximum electromagnetic enhancement at a particular wavelength. The presented simulation methodology will be helpful for various SERS related computational studies in future. Presented approach helps in understanding the effect of various parameters such as particle size, inter particle gap, excitation wavelength, etc. on the EM enhancement. Simulating various possibilities before fabrication helps in saving money and time. For device realization, gold nanoparticles are synthesized using Turkevich method to achieve uniform and spherical nanoparticles. Synthesized nanoparticles (40–45 nm radius) were drop casted on a porous cellulose paper substrate to realize a SERS substrate. Nanogaps created between nanoparticles become the hot-spot locations leading to electromagnetic coupling and hence the Raman signal enhancement. Paper based SERS substrate is tested with Rhodamine B (1 μM) test sample. Enhancement of 106 was observed with the developed SERS substrate. UV–Vis spectrometer and Raman spectrometers are used for various characterizations. • The work presents the comprehensive simulation strategy for nano particle-based SERS substrates. • Simulation results present the effect of nanoparticle size and inter particle gap on Raman enhancement. • Different configurations namely, single particle, dimer, trimer and tetramer are simulated and results are discussed. • Gold Nanoparticles are synthesized and SERS substrate using paper is prepared for Raman enhancement and results are presented. • Presented work demonstrates a low-cost SERS substrate with its analytical and experimental investigation. [ABSTRACT FROM AUTHOR]

Understanding past glaciation and deglaciation is vital for assessing present-day glacier dynamics and response to climate change. We focus on reconstructing past glacier fluctuations in Lahaul, north-west India, a region located between arid Ladakh and the humid the Pir-Panjal range. We focus specifically on six glaciers in the Miyar and Thirot catchments of varying size, aspect and debris cover. To reconstruct past terminus fluctuations of these glaciers, we used repeat terrestrial photography and historical archives as data sets and mapped the terminus positions and latero-terminal moraines in the field along with glacier terminus mapping from high to medium resolution satellite images (e.g. Corona, Hexagon, Landsat and LISS IV). Results show that since the little ice age, all the studied glaciers have experienced terminus retreat and area loss, with average values of 1.46 and 0.9 km2, respectively. Precipitation data show a statistically significant decreasing trend during the last century with an increasing trend in annual average maximum (Tmax) and minimum (Tmin) temperature. This warming trend is more statistically significant for Tmin. Although total ice loss at the six studied glaciers is considerable (5.48 km2), this varies both spatially (i.e. from glacier to glacier) and temporally. We attribute this variability to topographic controls such as glacier hypsometry and another non-climatic factor, i.e. varying degree of debris cover. [ABSTRACT FROM AUTHOR]

Abstract: Radio Frequency Identification (RFID) based systems have been used in different applications in the Architecture, Engineering, Construction, Owner and Operator (AECOO) industry. Applications are mainly designed for specific lifecycle stage of the facility and serve the needs of only one of the stakeholders. This would increase the cost and the labor for adding and removing tags and eliminate the chance of using shared resources. In this paper, the usage of tags permanently attached to components is proposed where the memory of the tags is used during the lifecycle by different stakeholders for data storage and handover. A Building Information Model (BIM) database is used for tackling the interoperability issues allowing different users to access and share the data. To securely and efficiently store data on RFID tags in ifcXML format, multi-level encryption together with role-based access control is applied on the data stored on RFID tags. Each user is assigned a certain role and can only access the part of data for which he has authorization according to a predefined role and the Access Control Policy. To explore the technical feasibility of the proposed approach, a case study considering both facilities management and emergency management has been implemented and tested at Concordia University. [Copyright &y& Elsevier]

A correlation study of gross calorific value of coal with parameters of proximate analysis (the content of ash, moisture, volatile matter and fixed carbon) was studied on more than 200 samples of coal from different mining areas across India. Gross calorific value is increased with the decrease of the content of ash, moisture respectively, and gross calorific value is also increased with the increase in the content of volatile matter and fixed carbon respectively. The relevant experimental data and graphs are very useful for industries to estimate the quality of coal. [ABSTRACT FROM AUTHOR]

In this study, field-based bathymetry of Neenkanth lake in the Lahaul Himalaya, India, was carried out. Volume estimation and calculation of peak discharge, and the results thus obtained have been compared with empirically derived values. Average morphological characteristics of this lake are the depth of 5.78 m, area of 22,925.80 m2 and volume of 132,511.12 m3 . The quantitative glacial lake outburst flood (GLOF) characteristics derived from the empirical models were found to be much higher than the measured values of the lake. A qualitative approach was adopted to determine dam breach assessment indicators, viz. dam type, dam geometry, height of the freeboard, etc. GLOF potential was found to be high considering majority of qualitative parameters; however, field measurements indicate a low risk. [ABSTRACT FROM AUTHOR]

Detailed field mapping of glacial and paraglacial landforms and optical dating from these landforms are used to reconstruct the early Holocene glaciation in the semi-arid region of Miyar basin, Lahaul Himalaya. The study identifies three stages of glaciation, of decreasing magnitude and termed, from oldest to youngest, the Miyar stage (MR-I), Khanjar stage (KH-II), and Menthosa advance (M-III). The oldest glacial stage (MR-I) has been established on the basis of detailed geomorphological evidence such as U-shaped valley morphology, trimlines, and truncated spurs. It is speculated to be older than the global Last Glacial Maximum (gLGM) based on the magnitude of DELA (Equilibrium-Line Altitude, 606m). No evidence of glacier expansion recorded from the basin correlates with the period of the gLGM. The second stage (KH-II) is well represented by extensive depositional features such as lateral and terminal moraines, drumlins, and lacustrine fills that have been constrained within 10 ± 1 to 6.6 ± 1.0 ka (Optically stimulated luminescence--OSL--ages), dating it to the early Holocene advance following the Younger Dryas cooling event. Exceptionally young glacial records of expansion are limited within a few hundred meters of the present termini of tributary glaciers and correlates with the 18th-century cooling event. Records of this glacial advance, termed the Menthosa advance, are clearly noticed in some tributary valleys. [ABSTRACT FROM AUTHOR]

Abstract: Copper(II) complex 1 catalyzes the oxidation of sulfides to sulfoxides with 30% H2O2 in high yields. Addition of a catalytic amount of TEMPO to the reaction mixture enhances the conversion and selectivity. Complex 1 can be recycled without loss of activity. [Copyright &y& Elsevier]

Polarization properties of PbSe clad optical waveguide are exploited theoretically, in the visible range at λ = 0.6328 μ m. Due to semiconducting nature, lead selenide (PbSe) supports lossy modes and showed oscillatory behavior in generated attenuation curves. It is observed that at different PbSe thicknesses, TM or TE guided modes may be selectively attenuated. High attenuation in waveguide modes mainly occurred due to the phase matching between lossy modes supported by PbSe cladding and lossless waveguide modes. It is proposed that by placing a high index buffer layer between PbSe cladding and waveguide, phase matching can be improved further. This property can be utilized to design highly efficient polarizers. Significant results are presented to show the effect of different buffer indices (1.55 , 1.88 and 2.67). At the buffer index value 1.88 , TE and TM pass polarizers can be designed with extinction ratios 501 d B and 316 d B respectively. Also, an extensively high attenuation loss of 243299 d B c m - 1 can be achieved with buffer index 2.67 for TM mode polarization. Obtained results are well supported by generated field plots for the proposed polarizing structures. [ABSTRACT FROM AUTHOR]

The present study documents the long-term trends in the temperature and precipitation of a poorly represented region, the Sikkim, eastern Himalaya using the Mann–Kendall non-parametric test and the Sen's slope estimator. Additionally, the normal distribution curves and Cusum charts have been used to identify the shifts in extreme events and to detect the points of change in the climatic data series for robust analysis. The minimum temperatures recorded a positive trend in Gangtok (0.036 ˚C year−1 from 1961 to 2017) as well as in Tadong (0.065 ˚C year−1 from 1981 to 2010) stations, while the maximum temperatures showed no trend in Tadong station from 1981 to 2010 which is consistent with the trend in Gangtok station for the overlapped period. However, it was negative for the overall assessed period (− 0.027 ˚C year−1 from 1961 to 2017) in Gangtok. The average temperatures in Gangtok recorded no trend whereas a positive trend (0.035 ˚C year−1 from 1981 to 2010) was observed at Tadong station. A similar positive trend in the average temperatures has been detected at Gangtok also for the overlapped period. Accelerated warming was noticed during the last two decades with an increase in the probability of extreme events of temperatures (minimum, maximum, average) at the higher end. Precipitation was found to be more variable across the observed period and suggested no trend in the study area. [ABSTRACT FROM AUTHOR]

The study reports new progress in the glacial chronology from new sites of the Chandrabhaga basin (CBB), in the transition between the monsoon-dominated Pir-Panjal and westerly-dominated Trans-Himalaya, in Lahaul Himalaya, northern India. In Lahaul, asynchronous timing and extent of late Quaternary glaciation have been reported (Owen et al., 1996, 1997, 2001; Eugster et al., 2016). The established oldest and most extensive Chandra glacial stage remains undated and speculative. We reconstrain the late Quaternary glacial history of the CBB using geomorphological mapping, Infrared Stimulated Luminescence (IRSL), and 10Be Terrestrial Cosmogenic Nuclide (TCN) surface exposure dating. Four local glacial stages, the Chandra, Batal, Dali, and Mayar, are dated to 152 ± 37 ka, 43 ± 3 ka, 21 ± 2 ka, and Little Ice Age (LIA), respectively. The Chandra glacial stage occurred during the late Marine Isotope Stage 6 (MIS 6; 186 ± 30 – 113 ± 10 ka), characterized by thick lacustrine deposits, rock benches, and ice-polished bedrock along the trunk valleys. We provide the first account of the numerical dating for the much-awaited timing of the oldest Chandra glacial stage (Local Last Glacial Maxima; LLGM) in the region (Owen et al., 1996, 1997, 2001). The LLGM in the CBB is much older than previously thought, consistent with some north-western Himalayan glacial records (Owen et al., 2006; Dortch et al., 2010; Hedrick et al., 2011; Orr et al., 2017, 2018). The Batal glacial stage occurred during the early MIS 3 and is dated from 47 ± 2 to 41 ± 2 ka, represented by the thick lacustrine deposits and impressive terraces. The Dali glacial stage occurred during the Global Last Glacial Maxima (GLGM), characterized by a series of latero-frontal recession moraines, and is dated from 33 ± 3 to 13 ± 1 ka. The Mayar advance is characterized by confined tributary valley glaciers, possibly linked to the LIA advance reported in the Kulti valley (Saha et al., 2019). The equilibrium line altitude (ELA) rose by ∼486 m from the Chandra stage to the present day. Reconstructed ELA altitudes and glacial landforms demonstrate that the glaciations have become progressively less extensive through time for this part of the western Himalayas. The change of glaciation pattern during the later part of the Quaternary is like other regions of the orogen, such pattern of glaciation reflects regional climatic forcing. • We present novel 31 k-feldspar IRSL and 12 cosmogenic 10Be ages for Chandrabhaga basin, Lahaul Himalaya, northern India. • We reconstrain the chronology for previously reported glacial stages of Owen et al. (1996, 1997, 2001). • We assign previously reported but undated oldest Chandra glacial stage with absolute dates. • Findings suggest that the Local Last Glacial Maxima in this region is much older than previously thought. • Our findings strongly question the previously reported extensions and rate of deglaciation during Global Last Glacial Maxima by Eugster et al. (2016). • Each glaciation becomes progressively less extensive in the Chandrabhaga basin over time. [ABSTRACT FROM AUTHOR]

The reactive silica of fly ash as that fraction of SiO2 which is soluble after treatment with hydrochloric acid and with boiling potassium hydroxide solution. The quantity of reactive silica is determined by subtracting from the total silica content that fraction contained in the insoluble residue both on dry basis. [ABSTRACT FROM AUTHOR]