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1.
Sharmin Kharrazi S.W. Gosavi T. Venkatesan J. Urban S.-W. Cheong 《Solid State Communications》2006,138(8):395-398
We report on the synthesis of TbMnO3 nanoparticles by chemical co-precipitation route and their structural, chemical bonding, magnetic and dielectric properties. It is shown that the interesting multiferroic properties of this system as reflected by the concurrent occurrence of magnetic and dielectric transitions are retained in the nanoparticles (size∼40 nm). However, the nanoparticle constitution and properties are seen to depend significantly on the calcination temperature. While the nanoparticles obtained by calcination at 800 °C correspond very well with the reported properties of single phase TbMnO3 (all the key magnetic and dielectric features near 7, 27 and 41 K, albeit with reduced dielectric constant) the nanoparticles obtained by calcination at 900 °C develop a Tb deficient skin which softens the transitions, reducing the dielectric constant further. 相似文献
2.
Akter Sharmin Tanabe Tomoki Maejima Satoshi Kawauchi Satoko Sato Shunichi Hinoki Akinari Aosasa Suefumi Yamamoto Junji Nishidate Izumi 《Optical Review》2016,23(2):354-359
Optical Review - To quantify the changes in optical properties of in vivo rat liver tissue, we applied diffuse reflectance spectroscopy (DRS) system using single-reflectance fiber probe during... 相似文献
3.
Sharmin RAHMAN Kazi Hanium MARIA Mohammad Saif ISHTIAQUE Arijun NAHAR Harinarayan DAS Sheikh Manjura HOQUE 《Turkish Journal of Chemistry》2020,44(4):884
Artificially fabricated hydroxyapatite (HAP) shows excellent biocompatibility with various kinds of cells and tissues which makes it an ideal candidate for a bone substitute material. In this study, hydroxyapatite nanoparticles have been prepared by using the wet chemical precipitation method using calcium nitrate tetra-hydrate [Ca(NO3)2.4H2O] and di-ammonium hydrogen phosphate [(NH4)2 HPO4] as precursors. The composite scaffolds have been prepared by a freeze-drying method with hydroxyapatite, chitosan, and gelatin which form a 3D network of interconnected pores. Glutaraldehyde solution has been used in the scaffolds to crosslink the amino groups (|NH2) of gelatin with the aldehyde groups (|CHO) of chitosan. The X-ray diffraction (XRD) performed on different scaffolds indicates that the incorporation of a certain amount of hydroxyapatite has no influence on the chitosan/gelatin network and at the same time, the organic matrix does not affect the crystallinity of hydroxyapatite. Transmission electron microscope (TEM) images show the needle-like crystal structure of hydroxyapatite nanoparticle. Scanning Electron Microscope (SEM) analysis shows an interconnected porous network in the scaffold where HAP nanoparticles are found to be dispersed in the biopolymer matrix. Fourier transforms infrared spectroscopy (FTIR) confirms the presence of hydroxyl group (OH-) , phosphate group (PO3-4) , carbonate group (CO2-3) , imine group (C=N), etc. TGA reveals the thermal stability of the scaffolds. The cytotoxicity of the scaffolds is examined qualitatively by VERO (animal cell) cell and quantitatively by MTTassay. The MTT-assay suggests keeping the weight percentage of glutaraldehyde solution lower than 0.2%. The result found from this study demonstrated that a proper bone replacing scaffold can be made up by controlling the amount of hydroxyapatite, gelatin, and chitosan which will be biocompatible, biodegradable, and biofriendly for any living organism. 相似文献
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The results of the innovative study on a new stationary phase with high efficiency based on ZnO nano and micro rod coating on fused silica are reported in this paper. ZnO nanorods with a diameter in the range of 70–300 nm and the length of about 500 nm, have been grown on fused silica fibers using a hydrothermal process. The extraction properties of the fiber were investigated using headspace solid-phase microextraction (HS-SPME) mode coupled with gas chromatography–mass spectrometry detection (GC–MS) for 1,4-dichloro-nitrobenzene, biphenyl and acenaphthene. The calibration curves were linear up to 102–107 ng L−1 (R2 > 0.995) with detection limits of 10−3 ng L−1 for biphenyl and acenaphthene and 10 ng L−1 for 1,4-dichloro-nitrobenzene. The RSD for single fiber and fiber-to-fiber were less than 7.0 and 11.5%, respectively. The high stability of the ZnO coating is proved at relatively high temperatures (up to 300 °C) with a high extraction capacity and long lifespan (more than 100 times). Promising recoveries (91–102%) were obtained in environmental water samples analysis by applying the proposed technique. 相似文献
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A data‐based monitoring scheme is proposed to detect decomposition in low density polyethylene reactors by combining principal component analysis with a priori information on the heat balance equations around the reactor. During normal operating conditions, the heat balance equation should close at all times within reasonable limits. If excess heat is generated in the reactor, the heat balance closure error will exceed a user specified threshold limit to indicate the possible onset of decomposition. However, since precise information required to formulate the exact energy balance equations was not available, principal component analysis (PCA) was used as a model identification tool. Results from a number of decompositions case studies from an industrial low density polyethylene/ethylene vinyl acetate autoclave reactor indicate that the method was able to detect the onset of decomposition with reasonable lead time.
7.
Arun K. Raha Mohammad R. Hassan Shariff E. Kabir Md. Manzurul Karim Brian K. Nicholson Ayesha Sharmin Luca Salassa Edward Rosenberg 《Journal of Cluster Science》2008,19(1):47-62
Reaction of [Os3(CO)10(CH3CN)2] with thianthrene at 80 °C leads to the nonacarbonyl dihydride compound [Os3(CO)9(μ-3,4-η2-C12H6S2)(μ-H)2] (1) and the 46-electron monohydride compound [Os3(CO)9(μ3-η2-C12H7S2)(μ-H)] (2). Compound 2 reacts reversibly with CO to give the CO adduct [Os3(CO)10(μ-η2-C12H7S2)(μ-H)] (3) whereas with PPh3 it gives the addition product [Os3(CO)9)(PPh3)(μ-η2-C12H7S2)(μ-H)] (4) as well as the substitution product 1,2-[Os3(CO)10((PPh3)2] (5) Compound 2 represents a unique example of an electron-deficient triosmium cluster in which the thianthrene ring is bound to cluster
by coordination of the sulfur lone pair and a three-center-two-electron bond with the C(2) carbon which bridges the same edge
of the triangle as the hydride. Electrochemical and DFT studies which elucidate the electronic properties of 2 are reported.
Dedicated to the memory of a great scientist, F. Albert Cotton. 相似文献
8.
Khorshed Alam Md. Mahmudul Islam Caiyun Li Sharmin Sultana Lin Zhong Qiyao Shen Guangle Yu Jinfang Hao Youming Zhang Ruijuan Li Aiying Li 《Molecules (Basel, Switzerland)》2021,26(24)
Microbial genome sequencing has uncovered a myriad of natural products (NPs) that have yet to be explored. Bacteria in the genus Pseudomonas serve as pathogens, plant growth promoters, and therapeutically, industrially, and environmentally important microorganisms. Though most species of Pseudomonas have a large number of NP biosynthetic gene clusters (BGCs) in their genomes, it is difficult to link many of these BGCs with products under current laboratory conditions. In order to gain new insights into the diversity, distribution, and evolution of these BGCs in Pseudomonas for the discovery of unexplored NPs, we applied several bioinformatic programming approaches to characterize BGCs from Pseudomonas reference genome sequences available in public databases along with phylogenetic and genomic comparison. Our research revealed that most BGCs in the genomes of Pseudomonas species have a high diversity for NPs at the species and subspecies levels and built the correlation of species with BGC taxonomic ranges. These data will pave the way for the algorithmic detection of species- and subspecies-specific pathways for NP development. 相似文献
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Dr. Chanchal Kumar Roy Syed Shaheen Shah Akter H. Reaz Sharmin Sultana Dr. Al-Nakib Chowdhury Dr. Shakhawat H. Firoz Dr. Md. Hasan Zahir Dr. Mohammed Ameen Ahmed Qasem Dr. Md. Abdul Aziz 《化学:亚洲杂志》2021,16(4):296-308
We demonstrate a facile efficient way to fabricate activated carbon nanosheets (ACNSs) consisting of hierarchical porous carbon materials. Simply heating banana leaves with K2CO3 produce ACNSs having a unique combination of macro-, meso- and micropores with a high specific surface area of ∼1459 m2 g−1. The effects of different electrolytes on the electrochemical supercapacitor performance and stability of the ACNSs are tested using a two-electrode system. The specific capacitance (Csp) values are 55, 114, and 190 F g−1 in aqueous 0.5 M sodium sulfate, organic 1 M tetraethylammonium tetrafluoroborate in acetonitrile, and pure ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) electrolytes, respectively. The ACNSs also shows the largest potential window of 3.0 V, the highest specific energy (59 Wh kg−1) and specific power (750 W kg−1) in [BMIM][PF6]. A mini-prototype device is prepared to demonstrate the practicality of the ACNSs. 相似文献
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Dongfei Chen Yanfang Wu Sharmin Hoque Richard D. Tilley J. Justin Gooding 《Chemical science》2021,12(14):5196
An accurate and robust method for quantifying the levels of circulating tumor DNA (ctDNA) is vital if this potential biomarker is to be used for the early diagnosis of cancer. The analysis of ctDNA presents unique challenges because of its short half-life and ultralow abundance in early stage cancers. Here we develop an ultrasensitive electrochemical biosensor for rapid detection of ctDNA in whole blood. The sensing of ctDNA is based on hybridization on a network of probe DNA modified gold-coated magnetic nanoparticles (DNA-Au@MNPs). This DNA-Au@MNPs biosensor can selectively detect short- and long-strand DNA targets. It has a broad dynamic range (2 aM to 20 nM) for 22 nucleotide DNA target with an ultralow detection limit of 3.3 aM. For 101 nucleotide ctDNA target, a dynamic range from 200 aM to 20 nM was achieved with a detection limit of 5 fM. This DNA-Au@MNPs based sensor provides a promising method to achieve 20 min response time and minimally invasive cancer early diagnosis.This study introduces a new electrochemical sensing strategy for the rapid detection of circulating tumor DNA (ctDNA) from whole blood in combination with a network of DNA-Au@MNPs with high sensitivity and excellent selectivity. 相似文献