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81.
Hydroxyapatite coating on stainless steel pre-coated with bovine serum albumin at ambient conditions
Nayar S Pramanick AK Sharma BK Mishra RK Bansal SK Prajapati A Sahu KK Das SK Pathak L Sinha A 《Colloids and surfaces. B, Biointerfaces》2006,48(2):183-187
A biomimetic process for coating of nanosized hydroxyapatite on stainless steel, which capitalises the dual nature of the protein bovine serum albumin in both metal binding and a strong affinity for calcium ions, has been developed. The novelty of the process lies in pre-conditioning the metallic surface using the above protein prior to its mineralization with hydroxyapatite at ambient conditions. The microporous morphology of these coatings may provide favourable solubility and resorbability as desired by many orthopaedic and orthodontic applications. 相似文献
82.
We present a methodology to analyze the stationary states and stability of complex fluid flows by using hybrid, discrete, and/or continuum multi-scale simulations. Building on existing theories, our scheme extracts dynamical and equilibrium characteristics from carefully chosen time integrations of these multi-scale evolution equations. Two canonical problems are presented to demonstrate the ability and accuracy of the formalism. The first is an investigation of flow-induced transitions seen in homogeneous, hard- rod liquid crystal suspensions subjected to a linear shear flow. In the second problem, we study the phenomenon of draw resonance, a dynamical instability in an isothermal fiber-spinning process, by using a multi-scale hybrid simulation that incorporates both stochastic and continuum models. 相似文献
83.
84.
Arvind Saxena Prashant Kumar Swaroop Banerjee K. P. Subramanian Bhas Bapat 《光谱学快报》2014,47(2):114-118
A hollow cathode sputter source is developed to trace the production of carbon clusters and study the influence of discharge current and argon gas pressure on cluster production using an optical emission spectroscopic technique. Optical emission spectra from the hollow cathode source reveal the production of the C2 Swan band. The sputter source is optimized for the maximum carbon cluster yield. The vibrational temperature analysis of the C2 cluster is carried out using the Boltzmann plot method. The dependence of vibrational temperature on argon gas pressure is discussed and the dominant method for C-C association in the glow discharge is suggested. 相似文献
85.
86.
Mohammad Shahid Syed S. Razi Priyanka Srivastava Rashid Ali Biswajit Maiti Arvind Misra 《Tetrahedron》2012,68(44):9076-9084
A new simple organic scaffold based on acenaphthene 4 was designed and synthesized. The chromogenic and fluorogenic properties of 4 toward different metal ions and anions were investigated in H2O/MeCN (8:2, v/v) solution. The probe 4 in the presence of Cu2+ exhibited strong static excimer emission at 507 nm along with a decrease in monomer emission at ~400 nm ratiometrically, attributed to a complexation through aldimine and amide groups of 4. Additionally, 4 upon interaction with different anions illustrated significant fluorescence enhancement with cyanide. However, interaction of complex, 4-Cu2+ with CN? revealed fluorescence quenching attributed to formation of stable [Cu(CN)x]1?x species in the medium. A naked-eye sensitive fluorescent green color of solution was changed to blue. The mechanism of interaction between 4 and Cu2+ and sensing of cyanide through Cu2+ displacement approach was confirmed by the change in optical behaviors and 1H NMR and ESI-MS spectral data analysis. 相似文献
87.
Arvind H. JadhavHern Kim 《Tetrahedron letters》2012,53(39):5338-5342
Selective deprotection of alkyl TBDMS ether in the presence of phenolic TBDMS ether using dicationic ionic liquid [tetraEG(mim)2][OMs]2 as a homogeneous catalyst showed significant catalytic activity in methanol at ambient temperature to produce respective alcohol in excellent yield. The present environmentally benign catalytic system is found to be very convenient, fast, high yielding, and clean method for selective desilylation of alkyl silyl ethers even in the existence of other sensitive organic functional groups such as aldehyde, methoxy, and acetate were also achieved. 相似文献
88.
The existence of entangled quantum states gives extra power to quantum computers over their classical counterparts. Quantum entanglement shows up qualitatively at the level of two qubits. We demonstrate that the one- and the two-bit Deutsch-Jozsa algorithm does not require entanglement and can be mapped onto a classical optical scheme. It is only for three and more input bits that the DJ algorithm requires the implementation of entangling transformations and in these cases it is impossible to implement this algorithm classically. 相似文献
89.
The optimal current difference lattice hydrodynamic model is extended to investigate the traffic flow dynamics on a unidirectional single lane gradient highway. The effect of slope on uphill/downhill highway is examined through linear stability analysis and shown that the slope significantly affects the stability region on the phase diagram.Using nonlinear stability analysis, the Burgers, Korteweg-deVries(KdV) and modified Korteweg-deVries(mKdV) equations are derived in stable, metastable and unstable region, respectively. The effect of reaction coefficient is examined and concluded that it plays an important role in suppressing the traffic jams on a gradient highway. The theoretical findings have been verified through numerical simulation which confirm that the slope on a gradient highway significantly influence the traffic dynamics and traffic jam can be suppressed efficiently by considering the optimal current difference effect in the new lattice model. 相似文献
90.
Anirban Garg Abdul Aziz Ali Krishnaiah Damarla Arvind Kumar Diganta Sarma 《Tetrahedron letters》2018,59(45):4031-4035
A facile, efficient and mild copper catalyzed strategy for cascade synthesis of various 1,4-disubstituted 1,2,3-triazoles from arylboronic acids, sodium azide and alkynes was developed by using aqueous bile salt NaDC solution as an accelerating medium. Low catalyst loading (only 1?mol% Cu source was sufficient for in situ generation of azide followed by azide–alkyne coupling), green solvent, use of bio-surfactant as additive and short reaction time make this protocol highly accessible and environment friendly. 相似文献