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31.
Particle signals are detected by two parallel measuring chains which consist of a detector and analog to digital converter. We have used OPT101 as photodiode and ADS7870 for A/D converter and the output signal from two parallel measuring chains is processed by on line correlation filter. This filter works as real time systems. A correlation algorithm has been applied for this work. The signal to noise ratio has been increased by applying correlation filter. The gain of the filter has been improved by introducing digital signal processing. 相似文献
32.
Deepak K. Pattanayak B. T. Rao T. R. Rama Mohan 《Journal of Sol-Gel Science and Technology》2011,59(3):432-447
This paper reviews selected aspects of research work carried out in bioceramics and bioceramic composites at the Ceramics
Laboratory IIT, Bombay, India. The focus here is in understanding and developing calcium hydroxyapatite (HA) bioceramics and
biocomposites, including calcium hydroxyapatite-titanium (HA-Ti) and calcium hydroxyapatite-polymethylmethacrylate (HA-PMMA).
Research involving apatite-wollastonite (AW) bioglass ceramics and bioceramic composites of AW with titanium as well as with
polymethylmethacrylate will be presented in a future article. HA powders were precipitated from solutions with varying Ca/P
ratios and calcined at a range of temperatures to investigate their structural evolution. HA-Ti composites were prepared by
powder metallurgical processes using HA powders calcined at 400 °C, followed by compaction at 600 MPa and subsequent sintering
at 1,000–1,200 °C. HA-PMMA composites containing up to 40 wt% PMMA were prepared by hot pressing at 150 °C and 150 MPa pressure.
The phases present in the various materials were identified by X-ray diffraction (XRD) and functional groups by FTIR, while
the sample morphologies were investigated by SEM. The bioactivity of the composites was evaluated by soaking them in simulated
body fluid (SBF) for 7 days, to evaluate their apatite-forming ability (a key indicator of bioactivity). The results obtained
are interpreted to aid in the development of “design rules” for the use of such biocomposite materials in specific biomedical
application. 相似文献
33.
Back Cover: Yoctoliter Thermometry for Single‐Molecule Investigations: A Generic Bead‐on‐a‐Tip Temperature‐Control Module (Angew. Chem. Int. Ed. 13/2014) 下载免费PDF全文
34.
35.
Deepak Singh Kapkoti Shilpi Singh Sarfaraz Alam Feroz Khan Suaib Luqman 《Natural product research》2020,34(12):1735-1742
AbstractNovel Mannich base derivatives of glabridin were synthesized and their antiproliferative activity were performed along with our previously reported glabridin-chalcone hybrids molecules (GCHMs) against various human cell lines MDA-MB-231 (breast adenocarcinoma), HEK-293 (embryonic kidney cell line), K562 (leukemia), MCF-7 (breast adenocarcinoma), HeLa (cervix adenocarcinoma), HepG2 (hepatocellular carcinoma) and WRL-68 (hepatic carcinoma). The result showed that the glabridin significantly reduced cell proliferation with IC50 ranges from 3.67 to 58.30?µM against all the tested cell lines. The remarkable reduction in antiproliferative activity 2’,4’-dimethoxyglabridin and GCHMs compounds with phenolic OH groups protected by methoxy (OCH3) groups suggested that the free OH groups are essential factor for the antiproliferative activity of glabridin and its derivatives. The Mannich base derivatives of glabridin showed moderate activity IC50 (2.20–>95.78?µM). Furthermore, in silico target identification analysis revealed that AKT1, DECR1 and NOS1 are the potential targets for glabridin and their derivatives. 相似文献
36.
Deepak Kumar Barange Veerababurao KavalaChun-Wei Kuo Cheng-Chuan WangR.R. Rajawinslin Janreddy DonalaChing-Fa Yao 《Tetrahedron》2014
An efficient regioselective synthesis of 4-iodo-2,3-disubstituted-2H-thieno[3,2-e][1,2]thiazine-1,1-dioxide derivatives via iodocyclization approach using iodine under mild reaction condition described herein. This coupling–iodocyclization strategy tolerated a variety of functional groups such as alkyl, cycloalkyl, phenyl producing the six-membered heterocyclic ring selectively. The resulting 4-iodo-2,3-disubstituted-2H-thieno[3,2-e][1,2]thiazine-1,1-dioxide was coupled with a variety of boronic acids (Suzuki coupling) and activated alkenes (Heck coupling). The iodo group was utilized for Sonogashira coupling followed by efficient transformation to azido precursor, which was used for the synthesis of various thieno-sultam linked with triazole. 相似文献
37.
The cross-coupling reaction of α-arylacetyl chlorides with triarylbismuths was studied under Pd-catalyzed conditions. The reaction was found to be facile under the established protocol and furnished high yields of α-aryl ketones in short reaction times. This work also demonstrated a facile synthesis of various regio-isomeric mono-, di- and tri-substituted α-aryl ketones in high yields. Triarylbismuths were employed as sub-stoichiometric multi-coupling organometallic nucleophiles in this coupling protocol. 相似文献
38.
Set-Valued and Variational Analysis - The epsilon-subdifferential of convex univariate piecewise linear-quadratic (PLQ) functions can be computed in linear worst-case time complexity as the... 相似文献
39.
40.
We study the steady state of the Abelian sandpile models with stochastic toppling rules. The particle addition operators commute
with each other, but in general these operators need not be diagonalizable. We use their Abelian algebra to determine their
eigenvalues, and the Jordan block structure. These are then used to determine the probability of different configurations
in the steady state. We illustrate this procedure by explicitly determining the numerically exact steady state for a one dimensional
example, for systems of size ≤12, and also study the density profile in the steady state. 相似文献