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731.
The synthesis of ditryptophan-pyridine conjugates and their binding to mercury ions is described. Conjugate 3 shows an excellent ability to sequester mercury from solution and rescue bacterial growth in a concentration-dependent survival assay. It is proposed that such compounds, composed primarily of bioessential/biodegradable components, could be potentially used as sequestrating agents for the removal of Hg(II) ions in detoxification strategies. 相似文献
732.
Sandeep Jain N. R. Srinivasa Raghavan 《Central European Journal of Operations Research》2009,17(1):95-110
This paper presents stylized models for conducting performance analysis of the manufacturing supply chain network (SCN) in
a stochastic setting for batch ordering. We use queueing models to capture the behavior of SCN. The analysis is clubbed with
an inventory optimization model, which can be used for designing inventory policies . In the first case, we model one manufacturer
with one warehouse, which supplies to various retailers. We determine the optimal inventory level at the warehouse that minimizes
total expected cost of carrying inventory, back order cost associated with serving orders in the backlog queue, and ordering
cost. In the second model we impose service level constraint in terms of fill rate (probability an order is filled from stock
at warehouse), assuming that customers do not balk from the system. We present several numerical examples to illustrate the
model and to illustrate its various features. In the third case, we extend the model to a three-echelon inventory model which
explicitly considers the logistics process. 相似文献
733.
Fiona M. Fennessy Andriy Fedorov Sandeep N. Gupta Ehud J. Schmidt Clare M. Tempany Robert V. Mulkern 《Magnetic resonance imaging》2012
There are many challenges in developing robust imaging biomarkers that can be reliably applied in a clinical trial setting. In the case of dynamic contrast-enhanced (DCE) MRI, one such challenge is to obtain accurate precontrast T1 maps for subsequent use in two-compartment pharmacokinetic models commonly used to fit the MR enhancement time courses. In the prostate, a convenient and common approach for this task has been to use the same 3D spoiled gradient-echo sequence used to collect the DCE data, but with variable flip angles (VFAs) to collect data suitable for T1 mapping prior to contrast injection. However, inhomogeneous radiofrequency conditions within the prostate have been found to adversely affect the accuracy of this technique. Herein we demonstrate the sensitivity of DCE pharmacokinetic parameters to precontrast T1 values and examine methods to improve the accuracy of T1 mapping with flip angle-corrected VFA SPGR methods, comparing T1 maps from such methods with “gold standard” reference T1 maps generated with saturation recovery experiments performed with fast spin-echo (FSE) sequences. 相似文献
734.
Ultrafast nonlinear optical response of carbon nanotubes functionalized with water soluble porphyrin
Jyotsana Gupta C. Vijayan Sandeep Kumar Maurya D. Goswami 《Optics Communications》2012,285(7):1920-1924
A new nanocomposite is obtained by functionalizing carbon nanotubes (CNTs) with a water soluble metalloprophyrin using a simple chemical technique and characterized by optical absorption, IR, and Raman spectroscopy. Results from spectroscopic studies indicate the noncovalent nature of interaction between CNTs and porphyrin. The ultrafast nonlinear response is characterized by measuring the nonlinear absorption coefficient and refractive index by z-scan technique in the femtosecond pulse regime. The nanocomposite is found to exhibit two-photon absorption (TPA) with a reasonably large nonlinear optical coefficient, whereas pure CNTs is known to exhibit saturable absorption. Design of such water soluble nanocomposites offers scope for obtaining materials with enhanced ultrafast optical nonlinearity. 相似文献
735.
A series of benzo[b][1,8]naphthyridines has been synthesized by Friedl?nder condensation of 2-aminoquinoline-3-carbaldehyde 1 (o-aminoaldehyde) with alicyclic ketones in basic medium. Benzonaphthyridines branched with various side-chains and substituents
are prepared with the aim of being investigated as a good fluorescent material. Electronic absorption and fluorescence properties
of some representative benzonaphthyridines in organic solvents, water-dioxane, and SDS, CTAB and Triton-X-100 micelles have
been examined. The linear correlation between solvent polarity and fluorescence properties is observed. This study may provide
new directions for the development of fluorescence probes as reporters of microenvironments of organized assemblies. 相似文献
736.
737.
738.
Sheokand Sandeep Kumar Prashant Jabeen Shakra Samra Kawaljeet Singh 《Journal of Solid State Electrochemistry》2023,27(3):727-738
Journal of Solid State Electrochemistry - In the present work, the effect of reaction temperature and urea concentration on the electrochemical performance of NiO nanoparticles is investigated. The... 相似文献
739.
Sunil Dattatray Chakave Shrikant Shete Dr. Sandeep Reddy Kandukuri Dr. Mark Montgomery Dr. Bhanu N. Manjunath Dr. Ravindra Punjaji Sonawane 《European journal of organic chemistry》2023,26(5):e202201205
The first total synthesis of des-hydroxy triticone A and B was achieved in 12 steps. The highly chemoselective, base mediated iodolactamization of olefins with N-OMe amide motif is a key highlight of the synthesis. 相似文献
740.
Khairnar Akshada Lohidasan Sathiyanarayanan Dubey Rahul Sankaran Sandeep 《平面色谱法杂志一现代薄层色谱法》2023,36(1):63-70
JPC – Journal of Planar Chromatography – Modern TLC - People all over the world are affected by the chronic, disabling autoimmune illness known as rheumatoid arthritis (RA). Herbal... 相似文献