IR@NEIST - North East Institute of Science and Technology (CSIR)
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Synthesis and coating of silica supported Nickel Oxide particles over ceramic pre-forms through sol-gel derived layered double hydroxides
Get PDFUnexpected deviation from diene behaviour of uracil amidine: towards synthesis of some pyrido[2,3-d]pyrimidine derivatives
Get PDFRhodium(I) carbonyl complexes of quinoline carboxaldehyde ligands and their catalytic carbonylation reaction
Get PDFSynthesis of dicarbonylruthenium(II) complexes of functionalized P,S chelating diphosphine ligands and their catalytic transfer hydrogenation
Get PDFPCR based molecular characterization of Nepenthes khasiana Hook. f.—pitcher plant
Get PDFNepenthes khasiana Hook. f. belonging to
monotypic family Nepenthaceae is a rare, endangered,
dioecious member of the carnivorous plant
found in North-East India. The plant is endemic to the
Indian state of Meghalaya and is distributed throughout
the state from West Khasi hills to East Khasi hills,
Jaintia hills and East, West to South Garo hills from
1,000 to ca. 1,500 m altitude. Multi-locus analysis
using PCR based Random Amplified Polymorphic
DNA (RAPD) and Inter Simple Sequence Repeats
(ISSR) markers were used for the first time to assess
the genetic diversities of N. khasiana Hook. f.
collected from different parts of Meghalaya. It was
observed that RAPD analysis showed more polymorphism
than ISSR fingerprinting in revealing genetic
polymorphism in N. khasiana Hook. f. The result of
cluster analysis by using UPGMA method showed
that the groups based on pooled RAPD–ISSR genetic
similarity were more similar than the groups based on
RAPD. Furthermore, genetic similarity reveals variability
within the population at Jarain of Jaintia hills,
while between populations the Baghmara region differs from the others with at least 40% dissimilarity.
The results show a broad range of genetic diversity
within the populations of N. khasiana Hook. f
Dicarbonylruthenium(II) complexes of diphosphine ligands and their catalytic activity
Get PDFThe hexa-coordinated chelate complexes of the type [Ru(CO)2Cl2(P-P)](1a,b) [where P-P = 9,9-dimethyl-
4,5-bis(diphenylphosphino)xanthene(a) and [bis(2-diphenylphosphinophenyl)ether(b)] have been synthesized
by reacting the polymeric precursor [Ru(CO)2Cl2]n with the ligands in 1:1 molar ratio. The complexes
1a,b are characterized by elemental analyses, Mass, IR and NMR spectroscopy together with the
single crystal X-ray structure determination of 1a. The compound 1a crystallizes in a monoclinic system
with space group C2/c showing a slightly distorted octahedral geometry around the Ru centre. The complexes
1a and 1b are thermally stable up to 300 �C and exhibit high catalytic activity in transfer hydrogenation
of aldehyde and ketones to corresponding alcohols. The complexes 1a and 1b show much higher
catalytic activity for the hydrogenation of aldehyde than ketones. In general, the catalytic efficiency of 1b
is higher compared with 1a
An efficient and stereoselective route to 1- deoxy- 5-hydroxy sphingosine analogues
Get PDFA short and efficient synthesis of 1-deoxy-5-hydroxy sphingolipid is described. The key steps involved are
a Jacobsen hydrolytic kinetic resolution (HKR) and Shibasaki 19s asymmetric Henry reactio
A thermal investigation on coals from Assam (India)
Get PDFA thermal characterization of two coal samples from Ledo and Tikak collieries of Makum
coalfield, Assam, India using XRD, FT-IR, and TGA was reported in this paper. The coal
samples were heated for 20, 40 and 60 min in a 1000-watt heater (temperature ∼250 °C) in
presence of air and characterized by XRD and FT-IR spectroscopy. Both the coals contain
amorphous and crystalline phases. The raw coals also contain very small peaks due to
quartz, calcite, gypsum, pyrite, and chlorite. The XRD patterns were found to change upon
heating. In the coals heated for 20 and 40 min, it was observed that both amorphous and
crystalline parts are common in them; crystalline part being the major one in the 40 min
heated samples. The XRD patterns of the samples heated for 60 min indicate the presence of
major quantities of α-quartz, hematite, and chlorite in them. They also show some new
peaks, which are assigned to be kaolinite, illite, magnetite and very small in comparison to
the amorphous portion in raw coals. α-quartz was found to be most stable crystalline phase
of silica in the coals. The crystallinity % (X-ray) of the coals heat-treated for different times
was determined and found to be increasing with time of heating. The FT-IR spectra of raw
and heat-treated coal samples at 250 °C were also recorded and compared. The spectra were
observed to be almost similar and it was observed that few functional groups disappear on
heating at 250 °C. The same coal samples were also characterized by thermogravimetric
analysis (TGA) and differential thermal analysis (DTA) techniques. On heat treatment in
air atmosphere up to 800 °C, 20–27% weight loss occurs due to removal of various
volatile materials. DTA results indicate the chemical reactivity of the coal sample initially
at 80–110 °C due to loss of water, and two other major reactions at around 420 and 530 °C
due to primary and secondary volatization
Seismotectonics in Northeast India : a stress analysis of focal mechanism solutions of earthquakes and its kinematic implications
Get PDFIn Northeast India, threemajor plates interact along two convergent boundaries: the Himalayas
and the Indo–Burma Ranges, which meet at the Assam Syntaxis. To clarify this tectonic
interaction and the underlying dynamics, we determine the regional seismotectonic stress
from the stress inversion of 285 double couple focal mechanism solutions of earthquakes
with an average magnitude of 5. We then compare the reconstructed stress regimes with the
available information about geodetically determined relative displacements.
North–south compression, in a direction consistent with India–Eurasia convergence, prevails
in the whole area from the Eastern Himalayas to the Bengal Basin, through the Shillong–Mikir
Massif and the Upper Assam Valley. E–W extension in Tibet is related to this N–S India–
Eurasia convergence. Not only does the major N–S compression affect the outer segments of
the Indo–Burma Ranges, it also extends into the descending slab of Indian lithosphere below
these Iranges, although stresses at depth are controlled by bending of the slab beneath the
Q1 Burmese arc.
The existence of widespread N–S compression in the Bengal Basin, far away from the
Himalayan front, is compatible with the previously proposed convergence between a Shillong–
Mikir–Assam Valley block and the Indian craton. E–W compression inside this block supports
the hypothesis of a component of eastward extrusion.
Stress inversion of focal mechanism solutions in the Indo–Burma Ranges reveals a complex
stress pattern. The Burmese arc and its underlying lithosphere experience nearly arcperpendicular
extension with ESE–WNW trends in the northernmost, NE-trending segment
and ENE–WSW trends in the main N–S arc segment. Such extensional stress, documented
from many arcs, is likely a response to pull from and bending of the subducting plate.
At the same time, the Indo–Burma Ranges are under compression as a result of oblique
convergence between the Sunda and Indian plates. The maximum compressive stress rotates
from NE–SW across the inner and northern arc to E–W near the Bengal Basin. This rotation is
consistent with the deformation partitioning reflected in the rotation of relative displacement
vectors, from a SSW-directed Sunda–Burma motion to aWSW-directed Burma–India motion.
As a consequence of this partitioning, the major belt-parallel fault zones show a variety of
movements across the main N–S arc segment, from right-lateral slip in the inner ranges to
oblique reverse-dextral slip in the outer ranges and pure thrusting in the westernmost foreland
belt
