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Iron ore as pozzolanic filler is an uncommon constituent of historic plaster rarely reported in any research. This paper presents one such study from western India where hematite instead of crushed bricks was identified as admixture in thirteenth–sixteenth-century CE Mughal masonry lime works of Daulatabad Fort. The outer/inner coat plasters from different locations of the fort were examined for morphological, mineralogical, chemical, and basic physical properties. The analytical investigative study was performed by optical microscopy, sieve analysis, X-ray fluorescence, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, SEM-EDX, and thermal analyzer. Although the plaster is dominantly made of micritic calcite and aggregate, incorporation of gypsum in the outer and inner coats has been detected and probably acted as a second binder. Cannabis sativa was mixed in the plaster, pointing to the knowledge of hempcrete technology by the makers of Daulatabad Fort. This investi...

This study documents a holistic approach, combining mineralogical, geochemical and textural data to characterize the decorative earthen plaster of the 2nd century BCE. Buddhist rock cut caves of Karle in Western India. The analytical examination was carried out by the use of a petrological microscope, Laser particle size analysis, thin section analysis, XRF (X Ray fluorescence), XRD (X Ray Diffraction), FTIR (Fourier Transform Infrared Spectroscopy), SEM (Scanning Electron Microscope) and Raman spectroscopy in addition to the monitoring of environmental parameters. The results indicate that the local clayey soil, which is abundantly available in the high rain fed western coastal areas, was utilized for the earliest earthen plaster works. The characteristics of the clay seem to have been modified by mixing calcite and an organic adhesive. Rounded sub-angular aggregates derived from disintegration of basaltic rock and rice husk were added to influence shrinkage properties of the plaster. In addition to a better understanding of the technology and composition of ancient India's early earthen plasterworks, scientific data from the analysis was used to plan the composition of restoration plaster.

This paper study the occurrence of aragonite–vaterite–calcite: Polymorphs of CaCO 3 in the ancient lime plaster works of south India’s Alampur group of temples that was under submerged condition due to past construction of Srisailam hydroelectric dam on Tungabhadra river just nearby the temples. For the proper examination of the Alampur plaster, we used analytical methods such as onsite observation, petrological thin section, XRF, XRD, FTIR, SEM – EDX and Raman Spectroscopy. The presence of polymorphs of CaCO 3 was confirmed through XRD, FTIR, SEM – EDX and Raman Spectra of the plaster. The occurrence of CaCO 3 polymorphs may be due to the action of invertebrates on initial submergence, self healing of the lime due to wet and dry cycle in the presence of Mg that promoted the formation of polymorphs. Microscopic mineralogical analysis showed mixing of sub-angular to sub-rounded, medium to low maturity sand and coarse silt character aggregates of silica rich lithology. The identification of phthalocyanine blue dye in the plaster by Raman spectroscopy may be part of present day rituals. This work is a holistic approach to find out the composition of ancient lime towards protecting the sand stone masonry of the temple by applying compatible lime plasters to arrest the deterioration.

The historic decorative lime plasters of Ellora caves, dated back to 6–11th century A.D have been investigated for their mineralogical, micro-structure and chemical characterization. The analytical studies were performed by means of optical microscopy, XRF, laser particle size analyzer, FTIR, XRD, Raman Spectroscopy, Scanning Electron Microscope and thermal analyzer. Traditional lime plaster is applied in 2–3 layers above the host rock but interestingly the techniques differ at India’s Ellora cave. From the analytical data it appears that all the lime plaster is composed of mixture of feebly dolomitic lime binder (aerial lime) mixed with fine to medium grained siliceous aggregates with addition of Cannabis sativa (Canabeacease) as an organic filler. The finding indicates that hempcrete technology was known to the ancient Indians in 6th century A.D and probably this is the first authentic report about the use of cannabis as filler in ancient lime plaster.

This paper addresses the results of mineralogical and physico-chemical investigation of 16 th century Mughal plaster of Bibi Ka Maqbara, the Taj of Deccan. The study investigated micro-morphological structure of various components of the plaster for the great to provide a basis for future restoration. The investigation on particle size distribution of aggregates in the plaster was carried and the result correlated to the strength of the plaster. Sieve/petrological analysis indicate the addition of creamy white zeolites (also detected by Raman spectrum) along with crushed amygdaloidal basalt of different grain sizes as aggregate in the plaster. The component material of the plaster and its purity has been studied through thermal analysis. The outer plaster layer was characterized for addition of hygroscopic organic additive with active carbonyl group by FTIR spectroscopy. The SEM images show salt crystallization in the pores as one of the reason for failure of plaster at some location, probably due to recent conservation with cement mortars/plaster of paris.

The optical absorption spectra of 3.6 MeV 12 C ions irradiated low-density polyethylene (LDPE) show the gradual increase in the optical absorption and the shift from the near UV to the visible region with increase in ion fluence. The increase in absorption may be attributed to the generation of a conjugated system of bonds, which are also corroborated by FTIR. Scanning electron microscopic (SEM) studies reveal that the formation of linear network structure occurred at relatively lower ion fluence of 5×10 13 ions/cm 2 .

Low-density polyethylene (LDPE) was irradiated with 4 MeV protons at different ion fluences. Chemical modifications were studied by UV–vis and Fourier transformed infrared (FT-IR) spectroscopy. Further, the changes in free volume holes were studied using positron annihilation lifetime spectroscopy. The different UV–vis absorption spectra show the maximum absorption at around 280 nm for the lower fluences whereas at the highest fluence a red shift is observed. This indicates formation of chromophoric groups that have the maximum absorption in that region. The formation of vinylidine, trans-vinylene, end-vinyl group, unsaturated linkage and carbonyl group were detected from FT-IR spectra. Positron annihilation lifetime spectroscopy reveals that the free volume hole size and their relative fraction first decrease, attaining a minimum value and subsequently increases with increase in ion fluence. These changes in free volume holes have been well correlated with the observed chemical transformations.

We analyze the electronic structure and adsorption binding energy of CO and CO2 molecules adsorbed on Ir4 and Pt4 clusters by using Density functional theory (DFT). It is found that the Ir4 cluster has more adsorption binding energy than Pt4 cluster. We show that the Ir and Ir - supported materials are good catalytic materials and could be useful for gas sensor applications.

Beryllium (Be)-decorated graphene with 585 double carbon vacancy defect and nitrogen-doped porphyrin defect are investigated for hydrogen storage applications using the first principle calculation based on density functional theory. It is found that the Be atom disperses well in the defective sites of graphene and prevents clustering. For the case of Be-decorated 585 double vacancy graphene, only two H2 molecules are adsorbed via Kubas interaction with the stretched H–H bond length of 0.8 Å. In Be-decorated porphyrin defect graphene system, four H2 molecules are molecularly chemisorbed with the H–H bond length of 0.77 Å. The chemisorptions are due to the hybridization between Be-p orbital and the H-[Formula: see text] orbital. The average binding energy of H2 molecule is found to be 0.43[Formula: see text]eV/H2 which lies within the required range that can permit recycling of H2 molecules under ambient conditions.