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221.
Kezheng Chen Weili Luo Zia Ur Rahman Yu Guo A. Schulte 《Journal of Dispersion Science and Technology》2013,34(3):471-476
Biocompatible magneto‐vesicles (MVs) with multiple magnetic nanoparticles encapsulated inside were synthesized by the hydration‐sonication method in the presence of magnetic fluid with a mixture of two types of phospholipid molecules. The dimension and the size distribution of these MVs are in the same order as the vesicles synthesized in the similar method, indicating that the encapsulation does not change vesicles' properties dramatically. Releasing fluorophore molecules—carboxylfluorescein (CF) from MVs demonstrates that MVs with DOPE/DDAB layers can be a new type of magnetic carrier for biomedical applications. 相似文献
222.
Ixone Esnal Dr. Ismael Valois‐Escamilla César F. A. Gómez‐Durán Arlette Urías‐Benavides María L. Betancourt‐Mendiola Prof. Iñigo López‐Arbeloa Dr. Jorge Bañuelos Prof. Inmaculada García‐Moreno Prof. Angel Costela Prof. Eduardo Peña‐Cabrera 《Chemphyschem》2013,14(18):4134-4142
A series of meso‐substituted boron‐bipyrromethene (BODIPY) dyes are synthesized and their laser and photophysical properties systematically studied. Laser emission covering a wide visible spectral region (from blue to orange) is obtained by just changing the electron donor character of the heteroatom at position 8. The additional presence of methyl groups at positions 3 and 5 results in dyes with a photostability similar to that of the unsubstituted dye but with much improved efficiency. Correlation of the lasing properties of the different dyes to their photophysical properties provides inklings to define synthetic strategies of new BODIPY dyes with enhanced efficiency and modulated wavelength emission over the visible spectral region. 相似文献
223.
Static and adaptive feedback control for synchronization of different chaotic oscillators with mutually Lipschitz nonlinearities 下载免费PDF全文
Muhammad Riaz Muhammad Rehan Keum-Shik Hong Muhammad Ashraf Haroon Ur Rasheed 《中国物理 B》2014,(11):227-235
This paper addresses the control law design for synchronization of two different chaotic oscillators with mutually Lipschitz nonlinearities. For analysis of the properties of two different nonlinearities, an advanced mutually Lipschitz condition is proposed. This mutually Lipschitz condition is more general than the traditional Lipschitz condition. Unlike the latter, it can be used for the design of a feedback controller for synchronization of chaotic oscillators of different dynamics. It is shown that any two different Lipschitz nonlinearities always satisfy the mutually Lipschitz condition. Applying the mutually Lipschitz condition, a quadratic Lyapunov function and uniformly ultimately bounded stability, easily designable and implementable robust control strategies utilizing algebraic Riccati equation and linear matrix inequalities, are derived for synchronization of two distinct chaotic oscillators. Furthermore, a novel adaptive control scheme for mutually Lipschitz chaotic systems is established by addressing the issue of adaptive cancellation of unknown mismatch between the dynamics of different chaotic systems. The proposed control technique is numerically tested for synchronization of two different chaotic Chua's circuits and for obtaining identical behavior between the modified Chua's circuit and the R6ssler system. 相似文献
224.
Tabassum Nasir Matiullah Muhammad Rafique Saeed Ur Rahman Muhammad Khalil Naveed Anwar 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(3):1209-1215
In order to carry out indoor radon measurement in new and old buildings of the Dera Ismail Khan city, CR-39 based radon detectors were installed in bed rooms and sitting rooms/TV lounges in 25 (each) old and new houses and were exposed to indoor radon for 90 days. After processing, mean weighted average indoor radon concentrations in old and new houses were found to be 275 ± 33 and 86 ± 18 Bq m?3 whereas mean annual effective doses expected to be received by the occupants were 6.86 ± 0.79 and 2.1 ± 0.43 mSv year?1, respectively. From the measured weighted average indoor radon concentration, excess relative risk factor was calculated using the risk model of BEIR VI for the age group of 35 and 55 years. Average excess lung cancer risk was found to be 1.63 ± 0.19 and 1.35 ± 0.16 and 0.5 ± 0.10 and 0.4 ± 0.08 for old and new houses, respectively. 相似文献
225.
For air-cleaning, TiO2 photocatalysis represents one of the very efficient advanced oxidation processes (AOPs) that can decompose chemically and microbiologically stable volatile organic compounds (VOCs). However, the photocatalytic activity of nanocrystalline TiO2 powders can be significantly suppressed due to TiO2’s poor adsorption characteristics for organic compounds and its relatively low surface area. The present study sought to solve this problem by immobilising nanocrystalline TiO2 in the porous silicate substrate. Two titania sources were used in an aqueous solution form: a suspension from a TiO2 producer in Slovenia, Cinkarna Celje (CC-40) and a TiO2 sol, prepared by a low-temperature synthesis developed at the University of Nova Gorica (TiO2-UNG). Two different types of mesoporous silica were used: SBA-15 with an ordered hexagonal pore arrangement and KIL-2 with disordered inter-particle mesoporosity. The structural characteristics, adsorption properties and photocatalytic activity of catalysts deposited on aluminium plates as thin films were investigated. CC-40 exhibited higher adsorption and photocatalytic activity than TiO2-UNG due to the greater quantity of Ti-OH groups on its surface. The addition of mesoporous silica led to higher adsorption and catalytic activity for both TiO2 sources. SBA-15 was more efficient than KIL-2. 相似文献
226.
Unusual Structural Features in the Lysozyme Derivative of the Tetrakis(acetato)chloridodiruthenium(II,III) Complex 下载免费PDF全文
Prof. Luigi Messori Tiziano Marzo Rute Nazaré Fernandes Sanches Hanif‐Ur‐Rehman Prof. Denise de Oliveira Silva Dr. Antonello Merlino 《Angewandte Chemie (International ed. in English)》2014,53(24):6172-6175
The reaction between the paddle‐wheel tetrakis(acetato)chloridodiruthenium(II,III) complex, [Ru2(μ‐O2CCH3)4Cl] and hen egg‐white lysozyme (HEWL) was investigated through ESI‐MS and UV/Vis spectroscopy and the formation of a stable metal–protein adduct was unambiguously demonstrated. Remarkably, the diruthenium core is conserved in the adduct while two of the four acetate ligands are released. The crystal structure of this diruthenium–protein derivative was subsequently solved through X‐ray diffraction analysis to 2.1 Å resolution. The structural data are in agreement with the solution results. It was found that HEWL binds two diruthenium moieties, at Asp101 and Asp119, respectively, with the concomitant release of two acetate ligands from each diruthenium center. 相似文献
227.
A. Afaq Azmat Iqbal Amin Ur Rahman Naveed Khan Fazal-e- Aleem M. Mushraf Ansari 《Brazilian Journal of Physics》2016,46(5):489-495
Photodetachment of negative ions near surfaces is of great interest in view of its fundamental significance and technological applications. We reinvestigate the dynamics of photoelectrons in H? photodetachment near a partially reflecting spherical surface by the semiclassical closed-orbit theory. Reflection parameter R and curvature K is used to observe inelastic and spherical effects of the surface, respectively. The classical action is evaluated from the photodetached electron trajectories incident normally at the surface, arising simultaneously from the source and its image. The derived analytical formula of photodetachment cross section correctly recovers the results of reflective spherical surface published recently based on theoretical imaging method. 相似文献
228.
Ceyla Yorucu Katherine Lau Shweta Mittar Nicola H. Green Ahtasham Raza Ihtesham Ur Rehman 《应用光谱学评论》2016,51(4):263-277
Invasion of melanoma cells from the primary tumor involves interaction with adjacent tissues and extracellular matrix. The extent of this interaction is not fully understood. In this study Raman spectroscopy was applied to cryo-sections of established 3D models of melanoma in human skin. Principal component analysis was used to investigate differences between the tumor and normal tissue and between the peri-tumor area and the normal skin. Two human melanoma cells lines A375SM and C8161 were investigated and compared in 3D melanoma models. Changes were found in protein conformations and tryptophan configurations across the entire melanoma samples, in tyrosine orientation and in more fluid lipid packing only in tumor dense areas, and in increased glycogen content in the peri-tumor areas of melanoma. Raman spectroscopy revealed changes around the perimeter of a melanoma tumor as well as detecting differences between the tumor and the normal tissue. 相似文献
229.
Hussain J Begum N Hussain H Khan FU Rehman NU Al-Harrasi A Ali L 《Natural product communications》2012,7(5):615-616
Phytochemical investigation of Ajuga bracteosa Wall ex Benth. (Labiatae) resulted in the isolation of a new phenolic compound, ajuganane (1) and three known compounds, 3,4'-dihydroxy-3,6,7-trimethoxyflavone, 7-hydroxy-3,6,3',4'-tetramethoxyflavone and ursolic acid. The structure of the new compound was elucidated by detailed spectroscopic (1H, 13C NMR, COSY, HMQC, HMBC), and HR-EI-MS analysis. 相似文献
230.
V. F. Ur’yash V. N. Larina N. Yu. Kokurina A. V. Bakulin E. A. Kashtanov V. P. Varlamov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(1):1-8
Standard enthalpies of combustion and formation were studied, along with the enthalpy of interaction of chitin and chitosan
of different origins with water. The concentration of the water phase solution in chitin and chitosan saturated at 273 K was
determined by calorimetry from the enthalpy of melting of the water excess phase. The dependence of these properties on the
source, molecular mass, and degree of ordering of polysaccharides was demonstrated. 相似文献