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Glacier ice-thickness measurement and distribution is one of the essential variables to assess present status of glacier-water equivalent and its volumetric reserve as well as to model the future glacier dynamics under the climate changing scenario. Yet, substantial gaps in ice thickness information exist for the Himalayan glaciers. The present study provides a long-term assessment (1965–2016) of recessional and area change patterns, as well as the detailed field-based (2016–2017) Ground Penetrating Radar(GPR), derived ice-thickness measurement of the Menthosa Glacier, Lahaul Himalaya. Additionally, the study examines whether the modelled ice thickness from remote sensing data is consistent with the field-based GPR measurement and how can it be improved. The extensive field surveys coupled with the multi-temporal high (Corona KH-4A) to medium resolution (Landsat Enhanced Thematic Mapper+ (ETM+)/Operational Land Imager (OLI), Sentinel 2A-Multispectral Instrument (MSI)) remote sensing data and cross-sectional GPR surveyed profile measurements have been used to examine past half a century (1965–2016) glacier fluctuation and the recent ice-thickness estimations, respectively. The results show that the Menthosa Glacier receded by 301.5 ± 19.2 m during the past half a century (1965–2016) with an average annual retreat of 5.9 ± 0.4 m a−1, whereas glacier lost 0.09 km2 ice in the frontal section. Field measurement over the past one decade (2006–2017) also conforms to a continuous recessional pattern and substantial glacier degeneration particularly the extensive surface lowering and significant appearance of ice-cliffs in the ablation and lateral zones over this period. The GPR measurements (2017) show the minimum glacier ice thickness of 24 meters at 4691 m a.s.l. (in the lower part of ablation area) and maximum glacier ice thickness of 55 meters measured at 4758 m a.s.l. (in the upper left-side tributary part of ablation area). Moreover, the modelled ice thickness derived from remotely sensed data is having Root Mean Square Error (RMSE) between 38 to 72 ± 10 m as compared with GPR measured ice thickness. [ABSTRACT FROM AUTHOR]

The effect of varying acid and dye concentration on the absorption spectra of the bromo and iodo substituted dyes, bis(3,5-dibromo-2,4,6-trihydroxyphenyl)squaraine (SqBr) and bis(3,5-diiodo-2,4,6-trihydroxyphenyl)squaraine (SqI), is investigated. The formation of the J-type dimer aggregates are obtained by comparing the differences in the triplet excited state properties of the neutral and aggregated forms of the dyes by using time-resolved spectroscopy.

We investigated the prevalence of Shiga toxin-producing Escherichia coli (STEC) in hospitalized diarrhea patients in Calcutta, India, as well as in healthy domestic cattle and raw beef samples collected from [...]

Weak complexes of the monomer and aggregate of a squaraine dye with triplet sensitizers were studied. The decay to extablish the ground state monomer-aggregate equilibrium is discussed.

A study was conducted to analyze anionic dye Merocyanine 540 aggregation on nanostructured TiO2 films. The benefits of integrating dyes in organized assemblies for suppressing nonradiative decay of the excited-state sensitizer and reducing the aggregation effects on semiconductor surfaces were discussed. Results indicated that H-aggregates of the merocyanine dye are less efficient than its monomer counterpart in sensitizing titanium dioxide.

Research was conducted to examine the concept of directional energy transfer between different dye aggregates and monomer thionine by confining them in a reverse micellar environment. Varying amounts of monomer, dimer and higher order aggregates were obtained in dilute dye solutions by controlling the ratio of (dye)/(aerosol-OT). Results suggest the possibility of using H-type dye aggregates as antenna molecules to harvest light energy.

Spatiotemporal surface velocity measurements of the alpine valley type debris-covered Miyar Glacier of the Chandrabhaga (Chenab) basin, western Himalaya, were assessed based on the cross-correlation of Landsat images spanning nearly three decades (1992-2019). Long-term (1950-2015) temperature and precipitation trends were evaluated using Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation (APHRODITE) datasets. The mean velocity (1992-2019) of the Miyar Glacier is ∼29 m/yr, with spatial patterns revealing that the debris-covered tongue is nearly stagnant (∼5 m/yr) compared to the debris-free up-glacier zone (∼35 m/yr). The transition zone from clean to debris-covered ice in the mid-ablation area shows the highest long-term mean velocities of ∼60 m/yr during the observation period, likely resulting from a steep surface gradient and greater ice thickness than the other regions of this glacier. The slow-moving and nearly stagnant debris-covered area reveals the highest amount of surface lowering due to the expansion of supraglacial ponds. Miyar Glacier experiences summer speed-up of ∼67–80% in seasonal velocity compared to winter, interpreted as a result from enhanced basal sliding during summer months due to warmer temperatures inputting more meltwater into the subsurface drainage system. Inter-annual velocity variations are greatest in the upper glacier, with higher velocities observed more frequently in recent decades. Future work should aim to elucidate the causes of this pattern, considering the overall rising air temperature trend in the western Himalaya. [ABSTRACT FROM AUTHOR]

The spectra of the oxidized form of ruthenium(II)-cis-di(isothiocyanato)bis(4,4'-dicarboxy-2,2'-bipyridyl) or N3-dye has been studied. An aqueous solution has been prepared by reacting the title compound with pulse radiolytically generated radicals N3(super *) and Br2(super -*). N3-dye is considered to be one of the most promising sensitizers for light energy harvesting applications since it can convert light energy into electricity with an efficiency of 10%. Results show N3-dye has an absorption maxima at 320 and 740 nm.

Primary, secondary and tertiary amines undergo intermolecular carbon-carbon bond formation with alpha,beta-unsaturated esters and nitriles, catalyzed by photoelectron-transfer, using photosensitizers such as anthraquinone, acridone and dicyanoanthracene. Multiple-olefin-added products are obtained by adding photoelectron transfer-generated alpha-aminoalkyl radicals to olefinic substrates and subsequent hydrogen abstraction.