Physical and Earth Sciences & Technology

1.9.1 SCIENCE, TECHNOLOGY & SERVICE

Flexible Electro Magnetic Interference (EMI) Shielding Materials

NPL has designed and developed flexible Electro Magnetic Interference (EMI) shielding materials based on newly emerging technology of conducting polymers and conducting composites with LDPE, HDPE etc. Interest in applications for polyaniline for Electromagnetic interference (EMI) shielding and Electrostatic charge dissipation (ESD) has motivated NPL to set up a pilot plant for the bulk synthesis of polyaniline and its analogues. A stainless steel

double walled reactor of 200 liters capacity has been commissioned where the synthesis of polyaniline can be carried out at 0-5oC. A semiautomatic injection moulding machine of 20-60 gms capacity has also been installed where one

semiautomatic injection moulding machine of 20-60 gms capacity


can make conducting polymer composites of dimensions 6” x 6”. Composites of conducting polymers having both electrical and magnetic characteristics have also been prepared at NPL, which has applications in microwave range. Synthesis of conjugated polymers based on aromatic hydrocarbons for organic light emitting diode (OLED) applications have also been carried out. Recent results of NPL have indicated that poly aromatic hydrocarbons are soluble in organic solvents like benzene, chloroform. These polymers are fluorescent and show electro luminescent behaviour.

Soft Lithography Techniques for micro and nano-fabrication

Creation of small structures with feature sizes ranging from a few microns to sub-micron is of great technical relevance to Materials Science, Biological Sciences and Engineering Sciences. Conventional photolithography is used routinely to create structure down to ~0.50 micron features in semiconductor and VLSI devices. However, the facility is prohibitively expensive and poses severe limitations for smaller feature sizes. Moreover, it has very little control over the surface properties of the structures that are very vital for chemical and biological applications. Soft lithographic technique utilizing micro-contact printing (mCP) of self-assembled mono layers (SAM’s) has great potential in micro and nano-fabrication and would greatly compliment the existing conventional photolithography technique.

NPL has exploited Micro-patterning using micro contact printing (µCP), one of the variants of soft lithography to fabricate small structures on solid surfaces for micro fabrication, sensors-arrays, MEMS and biological applications. It is an alternate (non-photolithographic) technique to create patterns in metal thin films on a substrate with feature sizes in sub-micron to micron range. It comprises of soft contact printing of SAM precursor solution using an elastomer stamp that contains the relief structures. The SAM solution is transferred to the well-defined regions on substrates having micron and sub-micron sizes. The surfaces derivatized with SAM serves as nano-thick etch resist and the underivatized surface could be etched in standard metal etchants. Micro-contact printing can be used repeatedly without invoking the costly equipment required in photolithography and is experimentally convenient and cost effective. NPL is the first one in country to have initiated work on soft lithography and micro-contact printing.

First deterministic seismic hazard map of India and adjacent areas

CMMACS has prepared a seismic hazard map of the territory of India and adjacent areas using a deterministic approach based on the computation of synthetic seismograms complete with all main phases. The input data set consists of structural models, seismogenic zones, focal mechanisms and earthquake catalogues. There are few probabilistic hazard maps available for Indian subcontinent, however, this is the first study aimed to produce a deterministic seismic hazard map for the Indian region using realistic strong ground motion modeling with the knowledge of the physical process of earthquake generation, level of seismicity and wave propagation in anelastic media. The synthetic seismograms at a frequency of 1 Hz have been generated at a regular grid of 0.2° x 0.2° by the modal summation technique. Figure depicts the spatial distribution of the design ground acceleration in g. The estimated values of the peak ground acceleration are in agreement with the observed data available for the Himalayan region. Many parts of the Himalayan region have the DGA values exceeding 0.6 g. The epicentral areas of the great Assam earthquakes of 1897 and 1950 in the north-east India represent the maximum hazard with DGA values reaching 1.2-1.3 g. The peak velocity and displacement in the same region is estimated as 120-177 cm/sec and 60-90 cm respectively.

This is the first deterministic seismic hazard map prepared for India and adjacent areas. The realistic modelling of seismic hazard for the Indian Territory yields meaningful results validated by recent observations made in connection with events that occurred after 1998, the upper time limit of the catalogue we used. It also provides a powerful and economically valid scientific tool for seismic zonation and hazard assessment. The multi-disciplinary approach used in this map will help those earthquake and civil engineers who wish to undertake comprehensive and detailed study of earthquake hazard.

Signal duration calibrations and local Richter magnitudes for the earthquakes in and around North East India

RRL-Jorhat has established signal duration calibration empirical relations for each of 24 previously operated analog seismic stations (at different gains) while intending to determine duration magnitudes (MD) of the earthquakes in and around North East India during the period 1985-1999. The relations are evaluated by calibrating signal durations with known Local Richter Magnitudes (ML) for each analog station based on models I & II since the stations are operated at different gains. The models are of the form: Model - I: MD = C0 + C1 Log (S.D) + C2 D + C3 h; Model - II: MD = C0 + C1 Log (S.D) + C2 D + C3 h + C4[Log (S.D)]2, Where S.D is the signal duration in seconds, D, epicentral distance and h, focal depth are in kilometers. In order to compensate the curvature observed in the relation of Log (S.D) versus ML, a fourth variable, [Log (S.D)]2 is introduced in model - II. Using these relations and signal durations, duration magnitudes are computed. The models yield magnitudes having standard deviations as low as 0.07 units. Further, network duration magnitudes MD (A) are determined as the arithmetic mean of station magnitudes for each of several earthquakes. Estimates of MD (A) are found to scatter with respect to ML within 0.8 units. In order to attain local magnitudes conformable to ML, scatter of MD (A) needs to be minimized. In this connection, an effort has been made to quantify over - and under - estimations of station magnitudes with respect to ML. MD versus ML plots are obtained for each of 24 stations along with 1:1 lines. With respect to 1:1 line, over - and under - estimations of station magnitudes are computed and applied as corrections to station magnitudes. Using corrected station magnitudes, network duration magnitudes are determined for about 825 earthquakes in and around North East India during the period 1985-1999. These corrected MD (A) estimates are found to scatter within 0.5 units. That is, over - and under - estimations of station magnitudes account 0.3 units out of 0.8 units of scatter of MD (A) versus ML observations. These station factors are applied to station magnitudes yielding that the scatter of MD (A) versus ML reduces by about 0.1unit. In this way homogenized station magnitudes are obtained conformable to ML within ± 0.2 units.

Memory Effect in deformed helix ferroelectric liquid crystals (DHFLC)

NPL has studied the memory effect in deformed helix ferroelectric liquid crystals (DHFLC) material. Its occurrence has been established experimentally for the first time. The memory effect is dependent on the voltage and frequency of the applied pulse and the memory data has been analyzed by optical, electrical, hysterisis and dielectric behaviour. The DHFLC memory effect has also been tested at room temperature in Optically Addressed Spatial Light Modulators (OASLM) using hydrogenated amorphous photoconductor and dielectric mirror coating. It has been observed that the memory in OASLM was stable without any visible decay up to 72 hours by using DHFLC materials.

Long-range, High-resolution Forecast of Monsoon Rainfall with a Variable Resolution GCM

Efficient use of monsoon rainfall forecasts often requires long-range (such as for crop planning) and high spatial resolution (such as for location-specific sowing schedule); these are also the most challenging issues in contemporary weather prediction. As the monsoon is a large scale system, it is necessary to use a GCM to simulate and forecast monsoon. At the same time, the monsoon dynamics is affected by convective systems, which have scales as small as a few kilometers. CMMACS has presented an GCM configuration that appears to have considerable success in long-range forecasting of monsoon rainfall. The novel feature is the use of a zoom (variable resolution) centered over the monsoon region; this allows high spatial resolution over a domain of interest at a relatively low computational cost. Using climatological fields of monthly SST from AMIP (Atmospheric Model Intercomparison Project) and initial fields from NCEP (National Center for Environmental Prediction), CMMACS presented experimental forecasts for monsoon of 2003 (June –August) in C-MMACS website. The forecast for 2004 are online from 10th April 2004. Thus the lead of the forecast is more than two months for June rainfall and more than four months for August rainfall. While the initial (NCEP) fields are on an approximately 250 km x 250 km grid, the forecast fields, over the monsoon region, are at about 50 km x 50 km in resolution. The reliability of the forecasts is assessed in terms of 15-year model climatology for onset, monthly rainfall fields and inter-annual variability.

Quality System In NPL Standars

As a part of the WTO agreement all signatory nations are committed to remove barriers including technical barriers to international trade. One of the well identified barriers is in the field of standards and precision measurements. It has been decided that testing and calibration certificates issued by National Metrology Institutes (NMI) like NPL should be acceptable globally. To ensure this, a Mutual Recognition Arrangement (MRA) has been signed by 38 member countries of the ‘Meter Convention’. Under this arrangement equivalence of National Standards has to be established. NPL is actively involved in the exercise of carrying out key comparisons to establish equivalence of Indian National Standards with the rest of the world.

Asia Pacific Metrology Programme (APMP) accepts a quality system if it satisfies the following:

  • The implementation of a Quality System satisfying ISO/IEC 17025, and
  • Technical competence to provide Calibration and Measurement Service that can deliver the claimed uncertainties.

NPL has implemented the Quality System which has undergone peer review of experts from BIPM France, NIST USA, PTB Germany, and NML Australia.Our Calibration and Measurement Capabilities are 483 and entered in the Appendix ‘C’ of BIPM.


Quantum Hall Resistance Standard

Primary DC Standard of resistance based on Quantum Hall Effect (QHE) has been established by NPL to provide a powerful tool for calibration of standard DC resistors with combined uncertainty of 0.08 ppm. It is used worldwide to define, maintain and compare the unit of resistance. The metrological meaning of the QHE lies in the fact that the Quantized Hall Resistance is a function of fundamental constants ‘h’ and ‘e’ only and is independent of place and time

Automatic Optimization of gravity fields

Digitally implemented method for automatic optimization of gravity fields obtained from three-dimensional density interface using depth dependent density is developed by NGRI to interpret the measured gravity fields, wherein the density contrast above the interface is assumed to be varying continuously with depth, a phenomena well observed in many sedimentary basins all over the world. This invention provides means to obtain more accurate depth values of a basement interface and it has remarkable applications in gas and hydrocarbon exploration studies.

Multibeam echosounding for seafloor studies

Unlike the wide-swath bathymetry data generated by use of multi-beam echosounder, seafloor backscatter signal provides additional fine scale information related to small-scale seafloor roughness. In order to carry out work on angular backscatter signal data, processing of the raw data is essential for data normalization. This processed data is required to utilize for numerical modeling to infer seafloor micro-topographic roughness. Studies based on numerical model, e.g., composite roughness was successful for the purpose of seafloor classification and characterization employing processed multibeam angular backscatter data from manganese-nodules-bearing locations of Central Indian Ocean Basin. However, the composite-roughness model approach is protracted due to the inherent need for raw data processing including system-gain correction etc. In order to establish that tedious processing of raw backscattered values is unessential for efficient classification, hybrid Artificial Neural Network Architecture (ANN) has been developed at NIO. A successful employment of hybrid ANN, i.e., Learning Vector Quantization (LVQ) algorithm for unprocessed (raw) multibeam backscatter data indicates true real-time seafloor classification application.

Hydrocarbon and Geothermal energy exploration

Regions of thick sediments in three blocks holding promise of hydrocarbon deposits have been demarcated in the Narmada cambay regions on the basis of Magnetotelluric investigations and also integration of other geophysical data by NGRI. The areas have been docketed to NELP for exploration. A major geothermal reservoir, about 5 km thickness, in the west of Sumdo village, Puga valley with anomalous high conductivity (5-10 Ohm-m) has also been delineated by NGRI.

Hydrothermal hydrocarbons in the sediments

As a follow up to earlier geological and geophysical investigations of tectonically active region of the Andaman Basin (which is a typical back arc basin with strike slip faults and spreading ridge), NIO took up molecular characterization of organic matter in sediments. The characterization provides a clue on the nature and source of the hydrocarbons present and also the processes in play that lead to maturation of organic matter.

The analysis of core samples from representative setting in Andaman Back arc (water depth 2.9 –35 km) indicate that the hydrocarbons found here are of hydrothermal origin and are derived from thermal alteration of sedimentary organic matter, largely marine derived. One of the three core samples from the deep basin and adjacent to fault, contained more hydrothermal petroleum than those from the topographic high region. It is likely that hydrothermal fluids migrate from deeper strata to the recent sediments near surface and discharged into the water column

Isotopic evidences of past upwelling intensity in the Arabian Sea

The oceans store more carbon than the atmosphere, thus small changes in oceanic CO2 may produce large changes in atmospheric CO2. Gas exchange between the ocean and the atmosphere is particularly intense in the upwelling regions. Upwelling and its attendant high primary productivity play an important role in the biogeochemical cycling of the oceans. Upwelling regions serve as both sources and sinks for many biologically active elements and the upwelling zones are major sites for sequestering of carbon. In this context it becomes important to identify and understand the history of upwelling as it is recorded in deep-sea sediments. The planktic foraminifera are considered important indicators of climatic changes and ocean history.

NIO has carried out studies on oxygen and isotopic analyses which have been performed on the tests of planktic foraminifer species, Globigerina bulloids, Globigerinoides sacculifer, Neogloboquadrina dutertrei and Pulleniatina obliquiloculata to investigate Dd18O and Dd13C of shallow and deeper depth living planktic foraminifer species. High and low Dd18Oobl-bul and Dd13Csac-dut coincide respectively with the low and high flux of G. bulloides (established monsoon upwelling index). The tangible relationships between the flux of G. bulloides and oxygen and carbon isotope differences between the shallow and deeper depth habitat planktic foraminiferal species appear to suggest that Dd18O and Dd13C of surface and subsurface living foraminifera can be used as isotope indices of upwelling in the Arabian Sea.

Unusual rise in mercury-resistant bacteria in coastal environs

NIO has found as a part of regular coastal environmental impact assessment surveys, high counts of mercury-resistant bacteria (MRB) at various locations - both non-polluted and polluted, along the Indian coast. The sharp rise in mercury-resistance (even 250 mg concentration of Hg) may be due to substantial physiological changes in bacteria in response to the natural and anthropogenic processes. NIO surveys indicate that Chennai and Mumbai coastal regions receive a wide variety of industrial, urban and shipping related effluents and are among the most pollution affected zones along the Indian coast. Similarly, we do find a noticeable change in the coastal waters off Mangalore due to speedy industrialization and expanded harbour activities. Variety of effluents, some after treatment, reaches the seas. Ratnagiri along the west coast is yet another town receiving large amount of discharges from manufacturing units. The average concentration of Hg in the Indian Ocean environments has been shown to be on increase and is in the range of 44-1390 ng g-1 dried sediment and 0-2100 ng L-1 seawater. These maxima are higher than the global oceanic averages. The ecological implications of increased mercury tolerance could mean higher rates of biotransformation of toxic heavy metals, their higher mobilization through the marine food web and increased level of Hg in atmosphere, which may prove deleterious to life systems.

Novel genes and bioactive molecules from marine organisms

NIO conducted studies on some myctophid fishes, copepods (Acartia sp.), green mussel, sea cucumber and reef building corals, to sequence their genes and look for novel biomolecules. The common and abundantly occurring open ocean species of family Myctophidae (lantern fishes) are generally associated with the oxygen minimum layer and are active vertical migrators. Their physiological adaptations allow them to survive in sub-oxic condition even below 1000 m. DNA probing is carried out to locate the genes that encode special functions enabling myctophids to see in low light intensities, conserve energy for active vertical migration and adapt to low oxygen surroundings. Humans undergo similar stresses on high altitudes and during deep-sea dives. NIO has designed species-specific primers of genes and patent them. The sequences of the rhodopsin gene of this myctophid fish when aligned and compared to that of human being, a notable difference is noticed, possibly a big deletion might have occurred during the evolution.

NIO has developed innovative methods of getting pure coral and zooxanthellae DNA. The collagen peptides that are different in animal kingdom are special for these animals and have greater potential in medical applications, particularly in human bone repairs. DNA fragment of this biomedically important minicollagen gene of reef building corals is sequenced and species-specific primers designed.

NIO has also discovered extra ordinary fluorescent biomolecules from sea cucumber. These fluorescent molecules and fluorescent dyes are patented internationally. They are far superior in quality and stable more than a year even at the room temperature. Novel pharmaceutically important biomolecules are patented from an associated mangrove plant.

Marine fungus discovered to remove hydrocarbon contaminants

Polycyclic aromatic hydrocarbons (PAHs) are commonly found as contaminants in inland and estuarine water bodies and sediments. They are toxic to diatoms, gastropods, mussels and fish. Several bacteria and a few white rot fungi are reported to metabolize many of the PAHs . NIO used a marine fungal isolate # 312 obtained from decaying seagrass from a coral lagoon for degradation of PAHs such as phenanthrene and chrysenetried to use this fungus for degradation/removal of PAHs under marine conditions.

Bioremediation of toxic substances

Mercury has long been recognized as a widely distributed toxicant in the global environment due to its prolonged atmospheric exposure. Strategies for bioremediation of toxic mercury include microbe mediated enzymatic reduction of toxic mercury (inorganic and organic) to volatile elemental mercury. Initial experimentation on bioremediation using marine mercury resistant bacteria have been very promising, not only for dealing with mercury, but also as a host of other highly toxic xenobiotics.

NIO has found that one strain of Pseudomonas CH07 is able to degrade a variety of congeners of PCBs. Of the two most toxic coplanar PCBs present in clophen A-50, one congener CB-126 and one toxic sterically hindered congener CB-181 are found to be degraded completely and the other coplanar congener CB-77 was degraded by more than 40% within 40 hours (US patent: grant No. 6544773). This strain is able to remove Cd from growth medium containing 100 ppm of the toxic metal to more than 70%. The same bacterium has also been successfully used in a bioreactor system for the detoxification of toxic mercury wastewater. The usefulness of these natural mercury resistant marine bacteria in bioremediation of toxic waste containing mercury and other pollutants is very promising.

Study of toxic heavy metals in the soil/water systems in and around Lakwa oil field

The north eastern region of India occupies a prominent position in the history of natural resources and it contributes significant towards the growth of national economy. However, active exploration and exploitation of crude oil causes a large-scale disposal of formation waters, oil contaminated wastewaters and also spillage of crude oil. This complex nature of mechanisms of anthropogenic substances in the environment and its effect on human system viz. the atmosphere or soil during occupational (work place) or recreational activities assumes a great dimension in the environmental toxicology.

Since 1968, Lakwa became the major oil producing structure of the region with more than 200 oil producing wells. The unattended environmental degradation caused by the oil field developmental activities became a subject of concern.

RRL-Jorhat has studied the soil/water systems around Group Gathering Stations (GGSs) I and III within the Lakwa oil field region both laterally as well as vertically. Texturally sandy-clay-loam (80%) and sand loam (20%) represent the soil of the area. The mean soil background values for Fe, Cu, Cr, Zn, Pb, Ni and Co were found at the higher side within a broad range of fluctuation. The background values of water samples are within the stipulated guideline values of IS(1982) and WHO (1984). The major and trace metals within pond and stagnated water bodies showed marked seasonal variation. The higher values of Na, K, Ca and Mg over the background values can be attributed to the entry of oil-contaminated wastewater from the GGSs, which impart hardness to the water bodies. The heavy metal contents were found to be associated with the clay/silt fractions. The chemical partitioning of metal contents indicate higher association with the residual and Fe-Mn oxide fractions and possess less environmental risk.




Hydro-Biospheric Processes and Soil Moisture Variability for better crop

Vegetation and surface processes strongly affect evolution of soil moisture, which in turn affects local precipitation and monsoon variability. By using a one dimensional multilayered soil hydrology model CMMACS has investigated and quantified the effects of some of the key vegetation and surface processes on soil moisture dynamics. Effect of initial soil moisture condition and groundwater flux on evaporation processes is also investigated. The simulations clearly brought out the important role of parameters like root zone can play in the evolution of soil moisture. The calibration and evaluation of the model is carried out through a long-period (one year) simulation of soil moisture at select locations. Simulated results have shown profound effect of vegetation on soil moisture evolution as is evident from the figure.

Hydro-biospheric processes encompass a multitude of land surface–atmosphere dynamics at different scales. These processes play crucial roles in the evolution of soil moisture, microclimate, meso-scale circulation, local scale precipitation and regional scale monsoon variability. High initial soil moisture conditions may delay the onset of precipitation but increase its amount and may thus lead to high intensity storm activities. Understanding of hydro-biospheric processes is crucial for reliable monsoon forecast, estimation of regional and global water budget with enormous socio-economic implications.

Archaeological Explorations along Saurashtra coast

NIO’s marine archaeological explorations offshore at Mithi Virdi (Talaja Taluk) and onshore around Porbandar, along the Saurashtra coast brought interesting findings to light. Though stone anchors have been commonly reported from many sites along this coast, the anchors that are found at this particular site were unique and the biggest in the world. It was rather difficult to attribute functional value as these anchors lacked upper hole. Possibly, these resembling Indo-Arabia type were used for mooring.

Onshore remains in and around Porbandar gave clue to the late Harappan settlement here during 16 to 14th Century BC, almost similar to the Bet Dwarka. This also suggests that Harappan legacy of maritime activity continued till late Harappan period along this coast. The discovery of ancient jetties along the creeks here signifies that Porbandar was an active center of maritime activities in the past too.

1.9.2 HUMAN RESOURCE DEVELOPMENT

C-MMACS

  • Workshop on use of GPS Technology, GPS Data Analysis and Processing
  • Indo-US Workshop on "Peer Reviewed Online k-12 (10+2) Science Education (PROKSE): A Feasibility Study”(held at NEERI, Nagpur) Organised by C-MMACS
  • Training Course on the use of GPS Technology in Hazard Assessment and GPS Data Processing
  • International Conference on Scale Interacting and Variability of Monsoon (SiVOM)
  • National Workshop on Science and Technology for Regional Development The Case for the North-East India
  • Training Course on Fluid Physics in Geological Environments Jointly Organized by C-MMACS and JNCASR, Bangalore

NGRI

  • Training course on MT data interpretation, May 13-17, 2003.
  • Training course ICPMS and associated analytical techniques for geochemical, mineral exploration and environmental studies, June 21-25, 2003.
  • Training course on Rain water harvesting and artificial recharge.

NIO

  • Top rankers of SSC students visited laboratory under CPYLS
  • Training for students of BITS, Pilani on “Classification of Satellite Image using PCI Software PCIWORKS Ver 7.0”
  • Long Hydrographic Course held for Naval Officers of India, Vietnam, Sri Lanka, Nigeria & Mynamar.
  • Workshop on Uncertainty in Measurement at NPL, New Delhi
  • Brain Storming session on ultrasonics in healthcare and education




1.9.3 RECOGNITION & AWARDS

1.9.3 RECOGNITION & AWARDS
National Mineral Award 2003 Dr. C. Manikyamba, NGRI
CSIR Young Scientist Award 2003 for Earth Science Dr. V.M. Tiwari, NGRI
National Mineral Award, by Ministry of Coal & Mines Drs. Anil Chaubey & M.V.S. Guptha, NIO
P.R. Pisharoty Memorial Award Dr. M.R. Ramesh Kumar, NIO
Rajib Goyal Award Dr. Neeraj Khare, NPL
CSIR Young Scientists Award 2003 for Physical Sciences Dr. Sushil Kumar, NPL