While conventional cleaning to remove the coating from plasma chamber walls becomes essential to reproduce the desired materials on the target substrate for widespread applications, an attention ...towards wall-deposited materials is scarce. Recycling those waste materials to value-added product is of great importance for sustainable progress of our modern society. Herein, we investigated the materials deposited on the wall of plasma chamber, explored their promising features and compared them with conventionally grown materials. A mixture of ZnO and α-Fe2O3 (ZF) exposed to high energy plasma was collected from the wall (ZF-W) and also from the substrate (ZF-S) to check the feasibility of providing same quality products. With same lattice constant of hematite, magnetite and zinc ferrites, ZF-W differs from ZF-S in coercivity, saturation magnetization, ferromagnetic stoichiometry and defects. In addition, degradation of Methyl Blue (MB) dye in ZF-W without use of any external light sources are comparable, more stable and durable in comparison to ZF-S. The slight differences obtained in the property-performances between ZF-W and ZF-S are attributed to the cationic arrangement and the oxygen vacancy defects present in the structure. The study reflects the potentiality of ZF-W as a promising active material for wastewater treatment just as one can use ZF-S. These findings clearly depict that the unused products with altered intrinsic properties obtained after plasma treatment has similar or even better potential to its actual targeted product and thus can be utilized properly thereby saving cost and time and, hence generates an unexplored direction for the materials science community.
•ZnO/α-Fe2O3 composite deposited on plasma chamber wall (ZF-W) are investigated.•ZF-W is compared with plasma treated mixture deposited on target substrate (ZF-S).•Structural studies are conducted by ...XRD, TEM, PL, Raman and Mossbauer spectroscopy.•Cationic arrangement and oxygen vacancy defects play a role in structural variations.•ZF-W shows excellent methyl blue adsorption without any external light sources.
While conventional cleaning to remove the coating from plasma chamber walls becomes essential to reproduce the desired materials on the target substrate for widespread applications, an attention towards wall-deposited materials is scarce. Recycling those waste materials to value-added product is of great importance for sustainable progress of our modern society. Herein, we investigated the materials deposited on the wall of plasma chamber, explored their promising features and compared them with conventionally grown materials. A mixture of ZnO and α-Fe2O3 (ZF) exposed to high energy plasma was collected from the wall (ZF-W) and also from the substrate (ZF-S) to check the feasibility of providing same quality products. With same lattice constant of hematite, magnetite and zinc ferrites, ZF-W differs from ZF-S in coercivity, saturation magnetization, ferromagnetic stoichiometry and defects. In addition, degradation of Methyl Blue (MB) dye in ZF-W without use of any external light sources are comparable, more stable and durable in comparison to ZF-S. The slight differences obtained in the property-performances between ZF-W and ZF-S are attributed to the cationic arrangement and the oxygen vacancy defects present in the structure. The study reflects the potentiality of ZF-W as a promising active material for wastewater treatment just as one can use ZF-S. These findings clearly depict that the unused products with altered intrinsic properties obtained after plasma treatment has similar or even better potential to its actual targeted product and thus can be utilized properly thereby saving cost and time and, hence generates an unexplored direction for the materials science community.
Display omitted
Iron oxide-based nanostructures receive significant attention as an efficient adsorbent for organic dyes removal. The removal properties have strong dependency on the stoichiometry, phases, reactive ...edges, defect states etc present in the iron-oxides nanostructures. Herein, iron oxide/carbon composite with well-defined heterophased grain boundaries is synthesized by simple precipitation method and followed by calcination. The local structure, spin dynamics and magnetic properties of heterophased iron oxides/carbon composite are thoroughly investigated to explore its cationic and anionic dye removal capability. To validate the effectivity of the presence of heterogeneous grain boundaries, iron oxide/carbon nanocomposite with homogeneous grain boundaries is also examined. It was found that the hetero-phased iron oxide/carbon showed removal capacity of 35.45 mg g-1 and 45.84 mg g-1 for cationic (Crystal Violet) and anionic (Congo Red) dyes, respectively as compared to that of as-synthesised imidazole-capped superparamagnetic {\alpha}-Fe2O3 (25.11 mg g-1 and 40.44 mg g-1, respectively) and homophased iron oxide/carbon nanocomposite (9.41 mg g-1 and 5.43 mg g-1, respectively). The plausible mechanism on the local structural evolution of the heterophase in the course of calcination and increase of the removal capacity is discussed. A detailed dye adsorption investigation is presented including the adsorption kinetic study. The pseudo-second order kinetic model is found to be an appropriate one and suggests that the chemisorption is dominant factor leading to adsorption of dyes. Whereas Weber-Morris model indicate the strong influence of boundary layers of nanocomposite on the adsorption process.
The plasma deposition wall coated composite of ZnO and {\alpha}-Fe2O3 (ZF-W) after exposure to ~ 2000 {\deg}C, mostly considered as waste-materials and cleaned out from the deposition unit, was ...subjected to anneal at 300, 500 and 1000 {\deg}C to manipulate the structural properties. An evolution of defect states along with the structural changes has been identified as annealing temperature was varied. As a consequence, an unstable state of ZnFe2O4 was found to be stabilized at 500 {\deg}C and migration of Zn from ZnO causes the phase transformation from the {\alpha}-Fe2O3 to ZnFe2O4. While implemented for methyl blue adsorption/degradation without the effect of any external sources, the degradation for ZF-W annealed at 300 {\deg}C, 500 {\deg}C and 1000 {\deg}C were 84%, 68% and 82%, respectively. Compared to annealed structures, pristine ZF-W delivered the highest methyl blue adsorption efficiency of 86%. The changes in adsorption/degradation properties have been correlated with the simultaneous evolution of defects and structural properties of ZF-W as annealed at different temperatures. The plausible mechanism on the interaction of methyl blue with the composites on the adsorption/degradation is proposed. These findings give a clear indication on the importance of defects presence in the mixed metal oxide composite to obtain high-performance degradation/adsorption properties for sustainable wastewater treatment.
The Miocene ape (Sivapithecus) locality of Tapar in Kutch (Gujarat, India) has yielded a diverse rodent assemblage that includes: a new murine Progonomys prasadi sp. nov., a new gerbilline ...Myocricetodon gujaratensis sp. nov., a new rhizomyne Kanisamys kutchensis sp. nov. and a new sciurine Tamias gilaharee sp. nov., beside additional remains of Progonomys morganae, Dakkamys asiaticus, Prokanisamys sp., Sayimys sivalensis and Democricetodon fejfari. Morphometric and PAUP based phylogenetic analyses place Progonomys prasadi sp. nov. within the Progonomys lineage. The cladogram obtained for the Siwalik murines suggest that Progonomys was ancestral to all the modern and one extinct murine genera recovered from the Siwaliks. The advanced features of Myocricetodon gujaratensis sp. nov. indicate that it was an immigrant to the subcontinent in the late Miocene. The cladistic analysis performed on Kanisamys kutchensis sp. nov. shows that it shared several advanced characters with contemporaneous Kanisamys nagrii and Kanisamys sivalensis. Based on the biostratigraphical ranges of Siwalik rodents and the co-occurrence of advanced forms of new and already reported murines, a new gerbilline and a new sciurine, we propose an age of ∼10 Ma to the primate-bearing Tapar locality. Already reported stable isotope data on murines, and ecological preferences of modern counterparts of the fossil rodents and associated sharks and rays from Tapar locality, indicate that the Miocene ape Sivapithecus may have lived in a subtropical monsoonal forest close to the coast, very different from the present day arid conditions.
http://zoobank.org/urn:lsid:zoobank.org:pub:12CE1B44-22A0-450F-9588-6C7F25242771
We report here a diverse assemblage of sharks and batoids representing the genera Carcharhinus, Rhizoprionodon, Galeocerdo, Sphyrna, Myliobatis, Aetobatus, Dasyatis, Pastinachus, Himantura and ...Pristis from Tapar and Jangadia the two late and early Miocene sites, respectively, of Kutch (Gujarat, India). The shark Rhizoprionodon and batoids, Dasyatis rugosa, D. cf. probsti, Dasyatis sp., Pastinachus and Himantura are being reported for the first time from the Miocene of western coast of India. The presence of Carcharhinus sp., Rhizoprionodon sp., Lamna sp., Negaprion sp., Sphyrna lewini, Myliobatis sp., Aetobatus sp. in the early Miocene Khari Nadi Formation exposed at Jangadia suggest existence of lagoonal, near shore to outer shelf environment. The rich batoid assemblage at the Late Miocene hominoid (Sivapithecus) bearing site of Tapar indicates the presence of a fresh to brackish water environmental condition. The faunal similarity of Miocene chondrichthyan of Indian Ocean and the Mediterranean Sea regions has been assessed using the beta diversity (Sørensen-Dice coefficient) data. The early Miocene elasmobranchs from Kutch shows close affinities with those from Mediterranean Sea. Similarly, in the Indian Ocean region Miocene fauna of Kutch shows close similarity with those of Baripada Beds, Orissa, Bhuban Formation of Mizoram, Gogha Coast, Piram Island and Madagascar.
Tiki Formation is well known for the presence of rich vertebrate fossil assemblages including archosaurians, cynodonts, xenacanthids, hybodonts and actinopterygians in the Gondwana succession of ...India. Here, we report indeterminate Sphenodontia and indeterminate Lepidosauromorpha from the Late Triassic Tiki Formation. The presently reported early diverging lepidosauromorphs might have fed on small invertebrates and small vertebrates/insects. The presence of early diverging lepidosauromorphs from the Tiki Formation extends their geographic range from Europe, N. America and S. America to the Indian sub-continent during the Late Triassic Period. Further, the reports of archosauromorph assemblages and the aquatic vertebrates from the Tiki Formation have strengthened the idea of affinities of vertebrate assemblages between Laurasia and Gondwana sub-continents of the Pangea.
PDF
