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11.
Hebalkar N Kharrazi S Ethiraj A Urban J Fink R Kulkarni SK 《Journal of colloid and interface science》2004,278(1):107-114
Cadmium sulfide nanoparticles (approximately 5 nm), chemically capped using thioglycerol molecules, have been anchored onto silica particles (approximately 80 nm) functionalized with 3-aminopropyltrimethoxysilane. Transmission electron microscopy clearly showed that at a low concentration of cadmium sulfide, nanoparticles were discretely and more or less uniformly attached onto the silica particles. At a high concentration of cadmium sulfide nanoparticles, an approximately 6-nm-thick compact shell of cadmium sulfide was formed on the silica particles. In both cases the nanocrystalline nature of cadmium sulfide particles was preserved, as is evident from X-ray diffraction and optical absorption spectra. 相似文献
12.
Mst. Sharmin Sultana Shimu Shafi Mahmud Trina Ekwati Tallei Saad Ahmed Sami Ahmad Akroman Adam Uzzal Kumar Acharjee Gobindo Kumar Paul Talha Bin Emran Shahriar Zaman Md. Salah Uddin Md. Abu Saleh Sultan Alshehri Mohammed M Ghoneim Maha Alruwali Ahmad J. Obaidullah Nabilah Rahman Jui Junghwan Kim Bonglee Kim 《Molecules (Basel, Switzerland)》2022,27(3)
13.
Mohammad Arafat Hussain Farzana Alam Sharmin Akhtar Rupa Rayhana Awwal Soo Yeol Lee Md. Kamrul Hasan 《Ultrasonics》2014
Elasticity imaging techniques with built-in or regularization-based smoothing feature for ensuring strain continuity are not intelligent enough to prevent distortion or lesion edge blurring while smoothing. This paper proposes a novel approach with built-in lesion edge preservation technique for high quality direct average strain imaging. An edge detection scheme, typically used in diffusion filtering is modified here for lesion edge detection. Based on the extracted edge information, lesion edges are preserved by modifying the strain determining cost function in the direct-average-strain-estimation (DASE) method. The proposed algorithm demonstrates approximately 3.42–4.25 dB improvement in terms of edge-mean-square-error (EMSE) than the other reported regularized or average strain estimation techniques in finite-element-modeling (FEM) simulation with almost no sacrifice in elastographic-signal-to-noise-ratio (SNRe) and elastographic-contrast-to-noise-ratio (CNRe) metrics. The efficacy of the proposed algorithm is also tested for the experimental phantom data and in vivo breast data. The results reveal that the proposed method can generate a high quality strain image delineating the lesion edge more clearly than the other reported strain estimation techniques that have been designed to ensure strain continuity. The computational cost, however, is little higher for the proposed method than the simpler DASE and considerably higher than that of the 2D analytic minimization (AM2D) method. 相似文献
14.
Norbani Abdullah Zainudin Arifin Edward R. T. Tiekink Naima Sharmin Nur Syamimi Ahmad Tajidi Siti Amira Mat Hussin 《Journal of Coordination Chemistry》2016,69(5):862-878
A covalent mononuclear complex, [Cu(p–HOC6H4COO)2(cyclam)] (1), and two ionic mononuclear complexes, [Cu(cyclam)(H2O)2](p–CH3OC6H4COO)2 (2) and [Cu(cyclam)(H2O)2](p–CH3(CH2)15OC6H4COO)2·H2O (3), were formed from reaction of cyclam with [Cu2(p–HOC6H4COO)4(H2O)2], [Cu2(p–CH3OC6H4COO)4(H2O)2] and [Cu2(p-CH3(CH2)15OC6H4COO)4(H2O)2], respectively. These complexes were isolated as purple crystals with molecular structures showing distorted octahedral N4O2 geometry. Complexes 1 and 2 were irreversibly reduced to Cu(I) and oxidized to Cu(III), while 3 was redox inactive. Complex 2 reacted with N-(hexadecyl)isonicotinamide (L) to form [Cu(cyclam)(L)2](p–CH3OC6H4COO)2 (4). These complexes were thermally stable (Tdec > 200 °C for 1–3 and 174 °C for 4). Complexes 3 and 4 behaved as ionic liquids (melting temperatures lower than 100 °C) and exhibited mesomorphism. 相似文献
15.
Md Anisur Rahman Yujin Cha Liang Yuan Parasmani Pageni Tianyu Zhu Moumita Sharmin Jui Chuanbing Tang 《Journal of polymer science. Part A, Polymer chemistry》2020,58(1):77-83
Cobaltocenium-containing polyelectrolyte block copolymer nanoparticles were prepared via polymerization-induced self-assembly (PISA) using aqueous dispersion RAFT polymerization. The cationic steric stabilizer was a macromolecular chain-transfer agent (macro-CTA) based on poly(2-cobaltocenium amidoethyl methacrylate chloride) (PCoAEMACl), and the core-forming block was poly(2-hydroxypropyl methacrylate) (PHPMA). Stable cationic spherical nanoparticles were formed in aqueous solution with low dispersity without adding any salts. The chain extension of macro-CTA with HPMA was efficient and fast. The effects of block copolymer compositions, solid content, charge density, and addition of salts were studied. It was found that the degree of polymerization of both the stabilizer PCoAEMACl and the core-forming PHPMA had a strong influence on the size of nanoparticles. © 2019 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 77–83 相似文献
16.
Nousin Akter Ruhul A. Khan Stephane Salmieri Nusrat Sharmin Dominic Dussault Monique Lacroix 《Radiation Physics and Chemistry》2012,81(8):995-998
Chitosan (1 wt%, in 2% aqueous acetic acid solution) and starch (1 wt%, in deionised water) were dissolved and mixed in different proportions (20–80 wt% chitosan) then films were prepared by casting. Tensile strength and elongation at break of the 50% chitosan containing starch-based films were found to be 47 MPa and 16%, respectively. It was revealed that with the increase of chitosan in starch, the values of TS improved significantly. Monomer, 2-butane diol-diacrylate (BDDA) was added into the film forming solutions (50% starch-based), then casted films. The BDDA containing films were irradiated under gamma radiation (5–25 kGy) and it was found that strength of the films improved significantly. On the other hand, synthetic petroleum-based polymeric films (polycaprolactone, polyethylene and polypropylene) were prepared by compression moulding. Mechanical and barrier properties of the films were evaluated. The gamma irradiated (25 kGy) films showed higher strength and better barrier properties. 相似文献
17.
Nusrat Sharmin Ruhul A. Khan Dominic Dussault Stephane Salmieri Nousin Akter Monique Lacroix 《Radiation Physics and Chemistry》2012,81(8):932-935
Chitosan films were prepared by casting from its 1% (w/w) solution. Tensile strength (TS) and tensile modulus (TM) of chitosan films were found to be 30 MPa and 450 MPa, respectively. Silane monomer (3-aminopropyl tri-methoxysilane) (0.25%, w/w) was added into the chitosan solution (1%, w/w) and films were casted. Then films were exposed to gamma radiation (5–25 kGy) and mechanical properties were investigated. It was found that at 10 kGy, the values of TS and TM were improved significantly. Silane grafted chitosan film reinforced poly(caprolactone) (PCL)-based tri-layer composites were prepared by compression molding. Silane improved interfacial adhesion between chitosan and PCL in composites. Surface of the films was investigated by scanning electron microscope (SEM) and found better morphology for silane grafted films. 相似文献
18.
Dynamic Characteristics of a Microhollow Cathode Sustained Discharge with Split Third Electrodes for Potential Flow Application to Flow Velocimetry
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The dynamic behavior of a microhollow cathode sustained discharge with split third electrodes is experimentally investigated. The sustained discharge swells isotropically in the presence of a small amount of argon gas flow that is not clearly detectable with a conventional single third electrode. At high flow rates, the sustained discharge transitions to a fast-moving constricted discharge with an are shape. The modified discharge structure causes a shift in current distribution over the third electrodes, and the current peak location varies linearly with the flow rate over a certain flow range. Such linear behavior may be applied to in situ flow velocity measurement. 相似文献
19.
Shariff E. Kabir Faruque Ahmed Mohammad R. Hassan Ayesha Sharmin Daniel T. Haworth Tasneem A. Siddiquee Kenneth I. Hardcastle 《Journal of organometallic chemistry》2008,693(16):2657-2665
Reaction of [Re2(CO)8(MeCN)2] with 1,8-bis(diphenylphosphino)naphthalene (dppn) afforded three mono-rhenium complexes fac-[Re(CO)3(κ1:η1-PPh2C10H6)(PPh2H)] (1), fac-[Re(CO)3{κ1:κ1:η1-(O)PPh2C10H6(O)PPh(C6H4)}] (2) and fac-[ReCl(CO)3(κ2-PPh2C10H6PPh2)] (3). Compounds 1-3 are formed by Re-Re bond cleavage and P-C and C-H bond activation of the dppn ligand. Each of these three complexes have three CO groups arranged in facial fashion. Compound 1 contains a chelating cyclometalated diphenylnaphthylphosphine ligand and a terminally coordinated PPh2H ligand. Compound 2 consists of an orthometalated dppn-dioxide ligand coordinated in a κ1:κ1:η1-fashion via both the oxygen atoms and ortho-carbon atom of one of the phenyl rings. Compound 3 consists of an unchanged chelating dppn ligand and a terminal Cl ligand. Treatment of [Mn2(CO)8(MeCN)2] with a slight excess of dppn in refluxing toluene at 72 °C, gave the previously reported [Mn2(CO)8(μ-PPh2)2] (4), formed by cleavage of C-P bonds, and the new compound fac-[MnCl(CO)3(κ2-PPh2C10H6PPh2)] (5), which has an unaltered chelating dppn and a terminal Cl ligand. In sharp contrast, reaction of [Mn2(CO)8(MeCN)2] with slight excess of dppn at room temperature yielded the dimanganese [Mn2(CO)9{κ1-PPh2(C10H7)}] (6) in which the diphenylnaphthylphosphine ligand, formed by facile cleavage of one of the P-C bonds, is axially coordinated to one Mn atom. Compound 6 was also obtained from the reaction of [Mn2(CO)9(MeCN)] with dppn at room temperature. The XRD structures of complexes 1-3, 5, 6 are reported. 相似文献
20.
Norbani Abdullah Suhana Mohd Said Yanti Yana Halid Megat Muhammad Ikhsan Megat Hasnan Naima Sharmin Siti Amira Mat Hussin 《Journal of Coordination Chemistry》2016,69(19):2954-2971
Nickel(II) carboxylates [Ni(CH3(CH2)14COO)2(H2O)2] (1) and [Ni(C6H5COO)2(H2O)2] (2) were obtained from reactions of NiCl2·6H2O with CH3(CH2)14COONa and C6H5COONa, respectively. Complex 1 reacted with pyridine (pyr) to form [Ni(CH3(CH2)14COO)2(pyr)2(H2O)2] (3) and [Ni2(μ2-H2O)(CH3(CH2)14COO)4(pyr)4] (4) in the same reaction mixture, and reacted with cyclam to form an ionic complex, [Ni(CH3(CH2)14COO)(cyclam)(H2O)]CH3(CH2)14COO·4H2O (5). In contrast, 2 reacted with cyclam to form [Ni(C6H5COO)2(cyclam)] (6). Finally, 6 reacted with p-(hexadecyloxy)pyridine (L) to form an ionic complex, [Ni(cyclam)(L)2](C6H5COO)2 (7). Complexes 3–6 were single crystals. All complexes have octahedral Ni(II) center(s) and were magnetic. Complexes with cyclam as co-ligand were more thermally stable than those with pyridine and its derivative, L. Complexes 3 and 4 were mesomorphic after partial loss of water and/or pyridine ligands on heating. The ionic complexes 5 and 7 were not mesomorphic, but showed good thermoelectrical behavior with negative Se values in CHCl3 (?0.28 mV K?1 for 5; -0.39 mV K?1 for 7) and positive Se values in C2H5OH (+0.25 mV K?1 for 5; +0.20 mV K?1 for 7). 相似文献