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141.
Poly(o-phenylenediamine) with ladder-type structure was formed in aqueous hydrochloric acid medium below pH 1, while open ring-type amine derivative, i.e., ?NH2 functional group substitution of polyaniline structure, was obtained in 1:1 aqueous sulfuric acid medium from the chemical synthesis of the monomer o-phenylenediamine. However, poly(o-phenylenediamine) having structure like polyaniline derivative with free =NH functional groups was obtained by chemical synthesis in dimethyl sulfoxide medium. The ladder-type polymer was almost insoluble but the other two types of synthesized polymers having polar functional group substitutions were well soluble in polar organic solvent like dimethyl sulfoxide, N,N-dimethyl formamide, and tetrahydrofuran. The freestanding films were cast from dimethyl sulfoxide solution of both the soluble functional polymers. The polymers having different structures were doped with inorganic acid by solution doping technique and the doped polymers were characterized by various standard characterizations. In order to explore the electronic uses of the polymers like sensor and actuators, the influences of their structure on the doping ability as well as ionic properties of the sulfuric acid-doped polymers were compared. 相似文献
142.
We report the cloning, purification and cell proliferative activity of a novel recombinant GST tagged human granulocyte macrophage colony stimulating factor (GST-hGMCSF). The hGMCSF gene was PCR amplified from the cDNA of ACHN renal carcinoma cells and was cloned into the bacterial expression vector. The GST-hGMCSF was purified to homogeneity using glutathione agarose affinity chromatography and subsequently characterized by Western blot, circular dichroism (CD) and MALDI TOF-TOF analysis. Homology modelling studies revealed the possible binding domains of the recombinant cytokine with cognate receptor. The proliferation of THP-1, Raw 264.7, MCF-7 and U87MG cells upon GST-hGMCSF addition was found to be dose dependent. Hence, this functionally active recombinant cytokine has potential application in cancer therapy for stimulating facile growth recovery of normal cell population. 相似文献
143.
The near orifice spray breakup at low GLR (gas to liquid ratio by mass) values in an effervescent atomizer is studied experimentally
using water as a simulant and air as atomizing gas. From the visualizations, the near orifice spray structures are classified
into three modes: discrete bubble explosions, continuous bubble explosions and annular conical spray. The breakup of the spray
is quantified in terms of the mean bubble bursting distance from the orifice. The parametric study indicates that the mean
bubble bursting distance mainly depends on airflow rate, jet diameter and mixture velocity. It is also observed that the jet
diameter has a dominant effect on the bubble bursting distance when compared to mixture velocity at a given airflow rate.
The mean bubble bursting distance is shown to be governed by a nondimensional two-phase flow number consisting of all the
aforementioned parameters. The location of bubble bursting is found to be highly unsteady spatially, which is influenced by
flow dynamics inside the injector. It is proposed that this unsteadiness in jet breakup length is a consequence of varying
degree of bubble expansion caused due to the intermittent occurrence of single phase and two-phase flow inside the orifice. 相似文献
144.
In modern day scenario, biosorption is a cost effective separation technology for the removal of various pollutants from wastewater
and waste streams from various process industries. The difficulties associated in rigorous mathematical modeling of a fixed
bed bio-adsorbing systems due to the complexities of the process often makes the development of pure black-box artificial
neural network (ANN) models particularly useful in this field. In this work, radial basis function network has been employed
as ANN to model the breakthrough curves in fixed bed biosorption. The prediction has been compared to the experimental breakthrough
curves of Cadmium, Lanthanum and a dye available in the literature. Results show that this network gives fairly accurate representation
of the actual breakthrough curves. The results obtained from ANN modeling approach shows the better agreement between experimental
and predicted breakthrough curves as the error for all these situations are within 6%. 相似文献
145.
Siddhartha Sen 《Pramana》2002,59(2):351-357
A classical phase space with a suitable symplectic structure is constructed together with functions which have Possion brackets
algebraically identical to the Lie algebra structure of the Lie group SU(3). It is shown that in this phase space there are
two spheres which intersect at one point. Such a system has a representation as an algebraic curve of the form X
3+…=0 in C
3. The curve introduced is singular at the origin in the limit when the radii of the spheres go to zero. A direct connection
between the Lie groups SU(3) and a singular curve in C
3 is thus established. The key step needed to do this was to treat the Lie group as a quantum system and determine its phase
space. 相似文献
146.
147.
Adimurthi Siddhartha Mishra G.D. Veerappa Gowda 《Journal of Computational and Applied Mathematics》2007
We deal with a single conservation law with discontinuous convex–concave type fluxes which arise while considering sign changing flux coefficients. The main difficulty is that a weak solution may not exist as the Rankine–Hugoniot condition at the interface may not be satisfied for certain choice of the initial data. We develop the concept of generalized entropy solutions for such equations by replacing the Rankine–Hugoniot condition by a generalized Rankine–Hugoniot condition. The uniqueness of solutions is shown by proving that the generalized entropy solutions form a contractive semi-group in L1. Existence follows by showing that a Godunov type finite difference scheme converges to the generalized entropy solution. The scheme is based on solutions of the associated Riemann problem and is neither consistent nor conservative. The analysis developed here enables to treat the cases of fluxes having at most one extrema in the domain of definition completely. Numerical results reporting the performance of the scheme are presented. 相似文献
148.
Specific inhibition of p300-HAT alters global gene expression and represses HIV replication 总被引:3,自引:0,他引:3
Mantelingu K Reddy BA Swaminathan V Kishore AH Siddappa NB Kumar GV Nagashankar G Natesh N Roy S Sadhale PP Ranga U Narayana C Kundu TK 《Chemistry & biology》2007,14(6):645-657
Reversible acetylation of histone and nonhistone proteins plays pivotal role in cellular homeostasis. Dysfunction of histone acetyltransferases (HATs) leads to several diseases including cancer, neurodegenaration, asthma, diabetes, AIDS, and cardiac hypertrophy. We describe the synthesis and characterization of a set of p300-HAT-specific small-molecule inhibitors from a natural nonspecific HAT inhibitor, garcinol, which is highly toxic to cells. We show that the specific inhibitor selectively represses the p300-mediated acetylation of p53 in vivo. Furthermore, inhibition of p300-HAT down regulates several genes but significantly a few important genes are also upregulated. Remarkably, these inhibitors were found to be nontoxic to T cells, inhibit histone acetylation of HIV infected cells, and consequently inhibit the multiplication of HIV. 相似文献
149.
We show that a subspaceS of the space of real analytical functions on a manifold that satisfies certain regularity properties is contained in the
set of solutions of a linear elliptic differential equation. The regularity properties are thatS is closed inL
2 (M) and that if a sequence of functions fn in ƒn converges inL
2(M), then so do the partial derivatives of the functions ƒn. 相似文献
150.
Akula Aneesh Reddy Siddhartha Banerjee Aditya Gopalan Sanjay Shakkottai Lei Ying 《Queueing Systems》2012,72(3-4):193-218
We study the problem of distributed scheduling in wireless networks, where each node makes individual scheduling decisions based on heterogeneously delayed network state information (NSI). This leads to inconsistency in the views of the network across nodes, which, coupled with interference, makes it challenging to schedule for high throughputs. We characterize the network throughput region for this setup, and develop optimal scheduling policies to achieve the same. Our scheduling policies have a threshold-based structure and, moreover, require the nodes to use only the “smallest critical subset” of the available delayed NSI to make decisions. In addition, using Markov chain mixing techniques, we quantify the impact of delayed NSI on the throughput region. This not only highlights the value of extra NSI for scheduling, but also characterizes the loss in throughput incurred by lower complexity scheduling policies which use homogeneously delayed NSI. 相似文献