http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Rana I. Shakoor (검색결과 3 건)
- 무료
- 기관 내 무료
- 유료
-
Anam Naseer,Muhammad Mumtaz,Muhammad Raffi,Izhar Ahmad,Sabih D. Khan,Rana I. Shakoor,Shaista Shahzada 대한금속·재료학회 2019 ELECTRONIC MATERIALS LETTERS Vol.15 No.2
With the recent developments in the millimeter and sub-millimeter wave instruments and devices, there is a need to developelectromagnetic (EM) wave absorbing materials in these frequency bands for applications like electromagnetic interferencecontrol, electromagnetic compatibility, etc. In this work, carbon nanofi bers (CNF) were uniformly dispersed in a blend ofpoly(methyl methacrylate), polyvinylidene fl uoride and cyanoacrylate for air spray coating a fi lm on the cellulosic substrates. The samples were characterized for evaluation of their structure, morphology, electrical and EM absorption properties in0.15–1.2 THz range by X-ray diff raction, fi eld emission electron microscopy, I–V measurements and terahertz time domainspectroscopy. These coatings can conveniently be applied to the material surfaces by conventional air spray painting method,which makes this technique cost-eff ective as well as easy to deploy in various applications. The electrical conductivityenhancement in the samples has been attributed to the formation of conducting network by uniform distribution of CNFs inthe insulating polymer matrix. As a result, the shielding eff ectiveness (SE) has been observed to improve with the increasein CNF’s loading in the polymer matrix. The SE is also a function of frequency, which is attributed to the increase in theskin depth. A SE of 20 dB has been estimated in these samples for the frequencies 1 THz and higher, which is of signifi cantimportance for the use of this technique in practical applications.
-
Taj Muhammad Khan,Tauseef Shahid,Rana I. Shakoor 대한금속·재료학회 2015 ELECTRONIC MATERIALS LETTERS Vol.11 No.3
We report the successful synthesis of polycrystalline CdO nanomaterials at various process temperatures in the range from (180°C - 300°C) by a single step, conventionally simple and cost effective approach. The approach is based on hydroxide melts as solvents and termed as composite-hydroxide-mediated (CHM) approach. The effect of growth temperature on particle nucleation and consequently on the fabrication and purity of CdO nanostructures is investigated for a constant reaction time (24 h). As revealed by x-ray diffraction and Raman spectroscopy, CdO nanostructures can be reproduced in high purity with no traces by varying the synthesis temperature. These nanostructures have random orientations and non-uniform distribution with average crystallite sizes varying from 27 nm down to 7 nm. A study of the optical properties, based on photoluminescence, has demonstrated that emission peaks of CdO nanomaterials are centered at 491 nm and 528 nm which signifies purity of the product from the CHM approach. The direct bandgap determined for CdO (2.49 eV - 2.51 eV) exhibits a blue-shift with process temperature. The photoluminescence peak at 491 nm is attributed to near band-edge emission. Based on experimental results size and morphology manipulation, and possible growth mechanisms for the synthesized product are proposed with CHM at low temperature and without surfactant.
-
M. Raffi,Zaira Batool,Mashkoor Ahmad,M. Zakria,Rana I. Shakoor,Muhammad Aslam Mirza,Arshad Mahmood 한국섬유공학회 2018 Fibers and polymers Vol.19 No.9
Titanium dioxide (TiO2) is one of the excellent photocatalysts used for degradation of environmetal pollutants. In this work, 2.5, 5.0 and 7.5 wt.% of silver (Ag)-loaded TiO2 nanofibers of mean size 52-134 nm were synthesized by electrospinning method. These electrospun nanofibers were calcined at 500 oC to enable the transformation of Rutile (R) phase to Anatase (A), elimination of reaction moieties from the TiO2 matrix and subsequently formation of Ag clusters. The effect of Ag loading on the morphology, crystal structure, phase transformation, and band gap of these electrospun nanofibers have been characterized by scannining electron microscopy (SEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), raman spectroscopy and UV-visible spectroscopy. These nanofibers exhibited a red-shift in the absorbance edge and a significant enhancement of light absorption in the wavelength range of 250-550 nm. These electrospun nanofibers were investigated for photodecomposition of methylene blue (MB), and photocatalytic decolorization rates were determined by pseudo-first-order equation. The rate constants for the pure and those of 2.5, 5.0, and 7.5 wt% Agloaded TiO2 nanofibers were computed to be 0.1439 min-1, 0.1608 min-1, 0.1876 min-1, and 0.2251 min-1 respectively.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
