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排序方式: 共有940条查询结果,搜索用时 15 毫秒
51.
Swapan K. Bhattacharya Mahesh G. Varadarajan Premjeet Chahal Gopal C. Jha Rao R. Tummala 《Journal of Electronic Materials》2007,36(3):242-244
To realize embedded resistors on multilayer benzocyclobutene (BCB) either on-chip or on-board, a low-cost large format electroless
process for deposition of NiP and NiWP thin-film resistors using both low-temperature (25°C) and high-temperature (90°C) baths
has been developed. The electroless process exhibits uniform resistor thickness in the submicron range and offers low profile
and excellent adhesion to the BCB dielectric layer. The resistor films also act as a seed layer for direct electroplating
of copper traces. The NiP alloys can also be tailored to a variable temperature coefficient of resistance (TCR) with different
alloy compositions. The electroless process can be adopted in the PCB manufacturing industries with no additional investment.
This article is the first report on electroless plated thin film resistors on low loss BCB dielectric. 相似文献
52.
Groundwater management and development by integrated remote sensing and geographic information systems: prospects and constraints 总被引:12,自引:3,他引:12
Madan K. Jha Alivia Chowdhury V. M. Chowdary Stefan Peiffer 《Water Resources Management》2007,21(2):427-467
Groundwater is one of the most valuable natural resources, which supports human health, economic development and ecological
diversity. Overexploitation and unabated pollution of this vital resource is threatening our ecosystems and even the life
of future generations. With the advent of powerful personal computers and the advances in space technology, efficient techniques
for land and water management have evolved of which RS (remote sensing) and GIS (geographic information system) are of great
significance. These techniques have fundamentally changed our thoughts and ways to manage natural resources in general and
water resources in particular. The main intent of the present paper is to highlight RS and GIS technologies and to present
a comprehensive review on their applications to groundwater hydrology. A detailed survey of literature revealed six major
areas of RS and GIS applications in groundwater hydrology: (i) exploration and assessment of groundwater resources, (ii) selection
of artificial recharge sites, (iii) GIS-based subsurface flow and pollution modeling, (iv) groundwater-pollution hazard assessment
and protection planning, (v) estimation of natural recharge distribution, and (vi) hydrogeologic data analysis and process
monitoring. Although the use of these techniques in groundwater studies has rapidly increased since early nineties, the success
rate is very limited and most applications are still in their infancy. Based on this review, salient areas in need of further
research and development are discussed, together with the constraints for RS and GIS applications in developing nations. More
and more RS- and GIS-based groundwater studies are recommended to be carried out in conjunction with field investigations
to effectively exploit the expanding potential of RS and GIS technologies, which will perfect and standardize current applications
as well as evolve new approaches and applications. It is concluded that both the RS and GIS technologies have great potential
to revolutionize the monitoring and management of vital groundwater resources in the future, though some challenges are daunting
before hydrogeologists/hydrologists. 相似文献
53.
Vineet Kumar Anita Rani Lulua Hussain Priyamvada Jha Vijay Pal V. C. Petwal Jishnu Dwivedi 《Food and Bioprocess Technology》2017,10(2):407-412
The present investigation was carried out to study the effect of 4.8, 9.2, 15.3 and 21.2 kGy of electron beam (EB)-irradiation on major storage proteins viz. glycinin (11S) and β-conglycinin (7S), in vitro protein digestibility (IVPD), and trypsin inhibitor (TI) content in seeds of three soybean genotypes. Densitometry of SDS-PAGE protein profile revealed significant (P < 0.05) reduction in α’, α and β subunits of 7S fraction at all doses. This reduction was higher (P < 0.05) than the decline observed in acidic and basic subunit of 11S fraction. Basic subunit registered significant (P < 0.05) increase at specific doses in two genotypes. All the doses induced significant (P < 0.05) increase in IVPD, and the increase due to 9.2, 15.3 and 21.2 kGy was higher (P < 0.05) compared to 4.8 kGy dose. The impact on TI content was genotype-dependent. The study showed a higher (P < 0.05) decline in the concentration of 7S fraction compared to 11S fraction and improvement in IVPD of soybean seeds due to exposure to EB-irradiation, which may influence the functional and nutritional value of soy products processed from them. 相似文献
54.
Alok K. Singh Mrityunjay K. Jha 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(2):163-171
The present study investigates the hydrocarbon generative potential of the coal seams of Barka Sayal Area of South Karanpura Coalfield, India, using petrological and geochemical characteristics. These coals are vitrinite rich followed by liptinite and inertinite. Rank wise these are sub-bituminous ‘A’ to high volatile bituminous ‘C’ and fall in the early catagenesis stage of evolution. The presence of Type III kerogen and high hydrogen index value indicates excellent gaseous hydrocarbon generative potential, but low Tmax suggests a characteristic of immature source rock. The calculated high conversion (%) and sufficient oil yield (%) justifies the suitability of these coals for liquefaction processes. 相似文献
55.
56.
Mehrdad Irannejad Toney Fernandez Purushottam Joshi Zhanxiang Zhao Joris Lousteau Billy Richards Gin Jose Animesh Jha 《International Journal of Applied Glass Science》2013,4(3):202-213
Following on from Part I of this review article that focuses on the suitability of Er3+-doped tellurium oxide glass for optical amplification in fiber, this Part II article describes how the fiber gain data were then employed to engineer amplification in waveguides, which can be integrated with semiconductor pump sources. The gain characteristics and bandwidth of a phosphate modified tellurite waveguide formed on a GaAs substrate are discussed. The limiting structural compatibility of Er3+-doped tellurite glass with polydimethylsiloxane polymer for active–passive integration is overcome by adopting a nanoscale super-lattice approach for waveguide engineering. 相似文献
57.
Low‐level laser therapy (LLLT) is a form of phototherapy used to promote cell proliferation. This study investigates the potential role of LLLT in cellular proliferation of human monocytic leukaemia cells Tamm‐Horsfall Protein 1 (THP‐1) under in vitro conditions. Cells were irradiated with an 850 nm diode laser and exposed to doses ranging from 0 to 26.8 J/cm2. After irradiation, cells were incubated for 12 and 24 h to allow time for proliferation. Comet assay was conducted to evaluate genotoxicity of the irradiated cells. Trypan blue was used to estimate cytotoxicity, which peaked at the highest dose as expected. Preliminary results suggest that cell counts increase at low doses, whereas a decrease in cell number at high doses was noted compared with controls. Comet assay showed no significant difference between irradiated and non‐irradiated cells at low doses. In contrast, DNA damage increased at doses ≥8.9 J/cm2 and was comparable with the 100 μM hydrogen peroxide positive control at the highest fluence. It could be concluded that LLLT has the ability to stimulate the THP‐1 cell line to proliferate if supplied with the correct energy and dose.Inspec keywords: photodynamic therapy, laser applications in medicine, cellular effects of radiation, biological effects of laser radiation, DNA, diseases, semiconductor lasersOther keywords: photo‐stimulatory effect, LLLT, human monocytic leukaemia cells, cell proliferation rate, low‐level laser therapy, phototherapy, THP‐1, Comet assay, Trypan blue, cytotoxicity, DNA damage, wavelength 850 nm, time 12 h, time 24 h 相似文献
58.
V. D. Tathavadkar A. Jha M. P. Antony 《Metallurgical and Materials Transactions B》2001,32(4):593-602
Soda-ash roasting of the chromite mineral is commonly used worldwide for the production of watersoluble sodium chromate. The
formation of sodium chromate during the soda-ash roasting reaction depends on the oxygen partial pressure and availability
of oxygen at the reaction front. The effects of temperature, oxygen partial pressure, charge composition, and their roles
on the overall roasting reaction were studied in order to analyze the reaction mechanism. The influence of process parameters
such as the addition of alkali and process residue as the filler material on the overall reaction rate is discussed. The rate-determining
steps for the soda-ash roasting reaction are analyzed. The importance of the binary Na2CO3-Na2CrO4 liquid phase during the reaction in determining its speed is also examined. It is shown that the experimental results for
the roasting reaction can be best described by the Ginstling and Brounshtein (GB) equation for diffusion-controlled kinetics.
From the measured kinetics data, the apparent activation energy for the roasting reaction was calculated to be between 180
and 190 kJ · mol−1 in the temperature range from 1023 to 1210 K and between 35 and 40 kJ · mol−1 above 1210 K. 相似文献
59.
A number of chromophoric chain β-aryl-substituted (CCBAS) styryl cyanines (hemicyanines) have been synthesised by condensing substituted quaternised quinaldine bases with substituted benzophenones, with a view to studying the effect of the aryl substituents on their visible absorption and silver halide photosensitisation properties.The dyes absorb at longer wavelengths than the unsubstituted analogues, showing uniform bathochromic shifts and extra-photosensitisation properties, which corroborate the authors' previous findings.Irrespective of the nature of the substituent attached to the chromophoric β-phenyl group, electron withdrawing and donating groups result in a bathochromic shift of the visible absorption band and extension of the extra-photosensitisation in most cases. 相似文献
60.
Membrane proteins are involved in a number of important biological functions. Yet, they are poorly understood from the structure and folding point of view. The external environment being drastically different from that of globular proteins, the intra-protein interactions in membrane proteins are also expected to be different. Hence, statistical potentials representing the features of inter-residue interactions based exclusively on the structures of membrane proteins are much needed. Currently, a reasonable number of structures are available, making it possible to undertake such an analysis on membrane proteins. In this study we have examined the inter-residue interaction propensities of amino acids in the membrane spanning regions of the alpha-helical membrane (HM) proteins. Recently we have shown that valuable information can be obtained on globular proteins by the evaluation of the pair-wise interactions of amino acids by classifying them into different structural environments, based on factors such as the secondary structure or the number of contacts that a residue can make. Here we have explored the possible ways of classifying the intra-protein environment of HM proteins and have developed scoring functions based on different classification schemes. On evaluation of different schemes, we find that the scheme which classifies amino acids to different intra-contact environment is the most promising one. Based on this classification scheme, we also redefine the hydrophobicity scale of amino acids in HM proteins. 相似文献