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41.
Using positive and/or negative phase velocity conditions, characteristics of a planar non-integer dimensional (NID) chiral interface are explored for specific values of NID parameter. For this purpose, discussion is divided into four cases. It is noted how characteristics of the interface changes when the situation is changed from one case to another. Impact of variation of NID parameter on the reflected power is also noted for each case. 相似文献
42.
Kawaljeet Singh Samra Ravinder Singh Lakhwant Singh 《Journal of Macromolecular Science: Physics》2020,59(2):65-76
AbstractThe structural and optical effects of copper (50?MeV) and carbon (70?MeV) ion irradiation of low density polyethylene (LDPE) are described. X-ray diffraction (XRD) and differential scanning calorimetric (DSC) techniques were used to explore the structural behavior, while Fourier transform infrared (FTIR) and UV-visible spectroscopies were used to collect the optical data. Structural parameters, such as interplanar separation, distortion factor, crystallite size and degree of crystallinity, were measured to understand the change in the structural behavior of LDPE caused by the swift heavy ion irradiation. In the irradiated polymeric samples, the formation and growth of new carbon enriched species were revealed by the FTIR and UV-visible analysis, which led to the decrease of their optical bandgap energy with the increase of ion fluence. 相似文献
43.
Alaa A. A. Aljabali Mohammad A. Obeid Hamid A. Bakshi Walhan Alshaer Raed M. Ennab Bahaa Al-Trad Wesam Al Khateeb Khalid M. Al-Batayneh Abdulfattah Al-Kadash Shrouq Alsotari Hamdi Nsairat Murtaza M. Tambuwala 《Molecules (Basel, Switzerland)》2022,27(6)
Advanced innovations for combating variants of aggressive breast cancer and overcoming drug resistance are desired. In cancer treatment, ZnO nanoparticles (NPs) have the capacity to specifically and compellingly activate apoptosis of cancer cells. There is also a pressing need to develop innovative anti-cancer therapeutics, and recent research suggests that ZnO nanoparticles hold great potential. Here, the in vitro chemical effectiveness of ZnO NPs has been tested. Zinc oxide (ZnO) nanoparticles were synthesized using Citrullus colocynthis (L.) Schrad by green methods approach. The generated ZnO was observed to have a hexagonal wurtzite crystal arrangement. The generated nanomaterials were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), UV-visible spectroscopy. The crystallinity of ZnO was reported to be in the range 50–60 nm. The NPs morphology showed a strong absorbance at 374 nm with an estimated gap band of 3.20 eV to 3.32 eV. Microscopy analysis proved the morphology and distribution of the generated nanoparticles to be around 50 nm, with the elemental studies showing the elemental composition of ZnO and further confirming the purity of ZnO NPs. The cytotoxic effect of ZnO NPs was evaluated against wild-type and doxorubicin-resistant MCF-7 and MDA-MB-231 breast cancer cell lines. The results showed the ability of ZnO NPs to inhibit the prefoliation of MCF-7 and MDA-MB-231 prefoliation through the induction of apoptosis without significant differences in both wild-type and resistance to doxorubicin. 相似文献
44.
Rodolphe Obeid Jin-Young Park Rigoberto C. Advincula Franoise M. Winnik 《Journal of colloid and interface science》2009,340(2):142-152
We describe herein the properties at the air/water (A/W) interface of hydrophobically end-modified (HM) poly(2-isopropyl-2-oxazoline)s (PiPrOx) bearing an n-octadecyl chain on both termini (telechelic HM-PiPrOx) or on one chain end (semitelechelic HM-PiPrOx) for different subphase temperatures and spreading solvents using the Langmuir film balance technique. The polymer interfacial properties revealed by the π–A isotherms depend markedly on the architecture and molecular weight of the polymer. On cold water subphases (14 °C), diffusion of PiPrOx chains onto water takes place for all polymers in the intermediate compressibility region (5 mN m−1). At higher subphase temperatures (36 and 48 °C), the HM-PiPrOx film exhibited remarkable stability with time. Brewster angle microscopy (BAM) imaging of the A/W interface showed that the polymer assembly was not uniform and that large domains formed, either isolated grains or pearl necklaces, depending on the polymer structure, the concentration of the spreading solution and the subphase temperature. The Langmuir films were transferred onto hydrophilic substrates (silica) by the Langmuir–Blodgett (LB) technique and onto hydrophobic substrates (gold) by Langmuir–Schaefer (LS) film deposition, resulting in the formation of adsorbed particles ranging in size from 200 to 500 nm, depending on the polymer architecture and the substrate temperature. The particles presented “Janus”-like hydrophilic/hydrophobic characteristics. 相似文献
45.
Ravinder Singh Kawaljeet Singh Samra Ramneek Kumar Lakhwant Singh 《Indian Journal of Physics》2009,83(7):955-961
The samples of polypropylene (PP) have been irradiated with 120 MeV 64Cu9+ and 70 MeV 12C5+ ion beams, with the fluence ranging from 1 × 1013 to 1 × 1011 ions/-cm−2. UV-VIS and FTIR techniques have been used to study the chemical and optical properties of these irradiated polymers. UV
spectra revealed that the optical-gap energy decreases by 54 % with copper ion irradiation at the fluence of 1 × 1013 ions/cm2, whereas at the same fluence, carbon beam decreases the optical-gap energy by 20%. FTIR analysis of ion irradiated samples
revealed the presence of -OH, C = O and C = C bonds. Alkyne formation has been observed only in the case of copper ion irradiation.
相似文献
46.
V. Brimmell J. Constant H. A. Pedlingham E. P. Raynes A. K. Samra 《Liquid crystals》1989,6(5):545-551
The response times of ferroelectric liquid crystal devices are of great importance, and are known to be related to various physical properties of the chiral smectic C* phase, such as the spontaneous polarization, the cone angle and the rotational viscosity. We report measurements of the effect of the smectic phase transitions on the response times and show that these are influenced by the smectic C* to smectic A transition temperature. 相似文献
47.
S. A. Kahtani H. P. Chou M. A. Obeid 《Journal of Radioanalytical and Nuclear Chemistry》1987,109(1):201-211
The instrumental neutron activation analysis technique (INAA) was used in the qualitative and quantitative analysis of 48 geological samples from the Umm Al-Birak area in the Kingdom of Saudi Arabia. The samples were properly prepared together with their standards and simultaneously irradiated in a neutron flux of 2.4 ·1012 n·cm–2 s–1 in the reactor facilities of the National Tsing Hua University (THOR) in Taiwan. Gamma-spectra from the high resolution Ge(Li) detector were analyzed using the BRUTAl code. As a result of the analysis of the geological samples, 20 trace elements were identified qualitatively and quantitatively. These elements are: Co, Cr, Eu, Fe, Hf, K, La, Lu, Na, Rb, Sc, Sm, Ta, Tb, Th, U, Yb, Zn and Zr. The concentrations of these elements have been used in the investigations of the geochemistry of the Umm Al-Birak microgranite site using the BMDP computer code of the Ministry of Petroleum and Mineral Resources. This investigation showed that the high grade area is a differentiated rock that crystallized in a late stage of the Umm Al-Birak microgranite area. 相似文献
48.
49.
Omar M. Al-Shuja’a Abeer O. Obeid Dheya A.-H. Ali Ali G. El-Shekeil 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):255-260
Polymercaptobenzothiazole disulfide-copper complex PMBTS-Cu has been synthesized by reacting 2-mercaptobenzothiazole disulfide with CuCl2 in absolute ethanol and dimethyl sulfoxide (DMSO) under reflux for 24 h. PMBTS-Cu has been characterized by several techniques using electronic spectra, elemental analyses, FTIR spectroscopy, and its solubility has been investigated. DC electrical conductivity variation with temperature, in the range 300–500 K, after annealing for 24 h at 100°C, and doping with different ratios of I2, is determined for comparison. Doping was done in two ways: by mixing and chemically. Activation energies were calculated and the results were interpreted using the band energy model. DC electrical conductivity of I2doped PMBTS-Cu complex increased with increasing temperature due to the variation of the carrier concentration with temperature as in the case of semiconductors. PMBTS-Cu complex has a copper ion in its backbone and copper salt is known to be a good dopant. Thus, these materials are doped internally, so the doped polymer-Cu complex are only one or two orders of magnitude higher in DC electrical conductivity than the annealed state. However, the energy gap is very small, which suggests suitability in applications like photovoltaic cells. 相似文献
50.
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