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101.
102.
ABSTRACTThe present paper reports the experimental investigation of pool boiling heat transfer on multiscale functionalized copper surfaces. Multiscale functionalized surfaces are fabricated by employing the nano-second laser surface process (NLSP) technique. The heat transfer coefficients (HTCs) of functionalized surfaces are estimated experimentally by using water and acetone as pool liquid. Tests are performed at atmospheric pressure, and saturated pool boiling condition with heat flux varyies between 0 and 330 kW/m2. The maximum HTCs for functionalized surface and reference polished surface were found to be 41,500 W/m2K and 23,000 W/m2K, respectively, with water and 22,000 W/m2K and 14,000 W/m2K, respectively, with acetone. 相似文献
103.
Ranjan K. Mallik 《Journal of Difference Equations and Applications》2013,19(6):501-521
A closed form solution of a third order linear homogeneous difference equation with variable coefficients is presented. From it, the solution for the special case of an equation with constant coefficients is also obtained. 相似文献
104.
An inverse problem is solved for estimating fuel cell operating parameters such as current density, pressure and fuel flow rate (FFR) separately and then simultaneously two parameters in an internal reforming solid oxide fuel cell (IRSOFC). Initially, a mathematical model for the forward problem is developed to simulate the IRSOFC steady state operation and its performance in terms of power output and then an inverse problem is solved for recovering the above parameters using a simplex search minimization algorithm. The objective function (IRSOFC power) and the estimation accuracy are studied for the effects of initial guess values of the operating parameters and the number of iterations required for retrieval of these parameters. The objective function is represented by the sum of square of the error between a given IRSOFC power and the power evaluated based on some arbitrary guessed values of the unknowns which is then regularized in an iterative manner for solution of the inverse fuel cell problem. The study reveals that a multiple combinations of parameters (current density, operating pressure and FFR) exist which provides guidelines for selecting feasible combinations of these parameters required for meeting a given power requirement. The results show relatively good agreement between the inverse and exact solutions. 相似文献
105.
The isotropic oscillator on a plane is discussed where the coordinate and momentum space are both considered to be non-commutative.
We also discuss the symmetry properties of the oscillator for three separate cases when the non-commutative parameters Θ and
for x and p-space, respectively, satisfy specific relations. We compare the Landau problem with the isotropic oscillator on non-commutative
space and obtain a relation between the two non-commutative parameters and the magnetic field of the Landau problem. 相似文献
106.
Muthu Thangaraj Bibhuti Ranjan Ramesh Muthusamy Arul Murugesan Robert Moonsamy Gengan 《Journal of heterocyclic chemistry》2019,56(3):867-885
A series of fused quinolinyl and quinolonyl pyrans were synthesized via a one‐pot reaction of quinolinyl and quinolonyl carbaldehydes, malononitrile, and a 1,3‐diketone. The reactions were catalyzed by a new humic acid supported 1‐butyl‐3‐methyl imidazolium thiocyanate ionic liquid under microwave irradiation conditions. Antimicrobial, antioxidant, and toxicity studies displayed various biological activities depending on structure of the pyrans. 相似文献
107.
Reactive oxygen species (ROS) forming enzymes are of significant interest as anticancer agents due to their potent cytotoxicity. A key challenge in their clinical translation is attaining site‐specific delivery and minimizing biodistribution to healthy tissues. Here, complexes composed of the ROS enzyme glucose oxidase (GOX), poly‐l ‐lysine‐grafted‐polyethylene glycol (PLL‐g‐PEG), and anti‐prostate specific membrane antigen (anti‐PSMA) monoclonal antibody are synthesized for localized delivery and uptake in prostate cancer cells. Formation of anti‐PSMA‐PLL‐g‐PEG/GOX results in nanoscale complexes ≈30 nm in diameter with a ζ‐potential of 6 mV. The anti‐PSMA‐PLL‐g‐PEG/GOX complexes show significant cytotoxicity (≈60% reduction in cell viability) against PSMA‐expressing LNCaP cells compared to unmodified GOX. Importantly, cytotoxicity in LNCaP cells occurrs concurrently with anti‐PSMA‐PLL‐g‐PEG/GOX uptake and increases in intracellular generation of ROS. These results demonstrate that cytotoxicity of ROS inducing enzymes can be enhanced by intracellular delivery compared to equivalent concentrations of free enzyme, providing a novel means for cancer therapy. 相似文献
108.
Verma Neha Sharma Vishal Kumar Raj Sharma R. Joshi M. C. Umapathy G. R. Ohja Sunil Chopra Sundeep 《Analytical and bioanalytical chemistry》2019,411(16):3477-3495
Analytical and Bioanalytical Chemistry - The detection of computer-generated document forgeries has always been a challenging task for forensic document examiners (FDE). With the aim to support the... 相似文献
109.
Pulak Ranjan Giri 《International Journal of Theoretical Physics》2008,47(10):2583-2590
We argue that it is possible to bind neutral atom (NA) to the ferromagnetic wire (FW) by inequivalent quantization of the
Hamiltonian. We follow the well known von Neumann’s method of self-adjoint extensions (SAE) to get this inequivalent quantization,
which is characterized by a parameter Σ∈ℝ(mod2π). There exists a single bound state for the coupling constant η
2∈[0,1). Although this bound state should not occur due to the existence of classical scale symmetry in the problem. But since
quantization procedure breaks this classical symmetry, bound state comes out as a scale in the problem leading to scaling
anomaly. We also discuss the strong coupling region η
2<0, which supports bound state making the problem re-normalizable. 相似文献
110.