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201.
Abdulrahman Th. Mohammad Sohif Bin Mat M. Y. Sulaiman K. Sopian Abduljalil A. Al-abidi 《Heat and Mass Transfer》2013,49(11):1587-1593
A computer simulation using MATLAB is investigated to predict the distribution of air stream parameters (humidity ratio and temperature) as well as desiccant parameters (temperature and concentration) inside the parallel plate absorber. The present absorber consists of fourteen parallel plates with a surface area per unit volume ratio of 80 m2/m3. Calcium chloride as a liquid desiccant flows through the top of the plates to the bottom while the air flows through the gap between the plates making it a cross flow configuration. The model results show the effect of desiccant mass flow rate on the performance of the dehumidifier (moisture removal and dehumidifier effectiveness). Performance comparisons between present cross-flow dehumidifier and another experimental cross-flow dehumidifier in the literature are carried out. The simulation is expected to help in optimizing of a cross flow dehumidifier. 相似文献
202.
Composite solid electrolytes in the system (1???x)Li2CO3–xAl2O3, with x?=?0.0–0.5 (mole), were synthesized by a sol–gel method. The synthesis carried out at low temperature resulted in voluminous and fluffy products. The obtained materials were characterized by X-ray diffraction, differential scanning calorimetry, scanning electron microscopy/energy-dispersive X-ray, Fourier transform infrared spectroscopy and AC impedance spectroscopy. Structural analysis of the samples showed an amorphous feature of Li2CO3 and traces of α-LiAlO2, γ-LiAlO2 and LiAl5O8. The prepared composite samples possess high ionic conductivities at 130–180 °C on account of the presence of lithium aluminates as well as the formation of a high concentration of an amorphous phase of Li2CO3 via this sol–gel preparative technique. 相似文献
203.
Zubair Ahmad Mahdi Hasan Suhail Issam Ibrahim Muhammad Wissam Khayer Al-Rawi Khaulah Sulaiman Qayyum Zafar Ahmad Sazali Hamzah Zurina Shaameri 《中国物理 B》2013,(10):192-196
In this paper, we present the effect of varied illumination levels on the electrical properties of the organic blend bulk heterojuction (BHJ) photodiode. To prepare the BHJ blend, poly(2-methoxy-5(2P-ethylhexyloxy) phenyleneviny- lene (MEH-PPV) and aluminum-tris-(8-hydroxyquinoline) (Alq3) are used as donor and acceptor materials, respectively. In order to fabricate the photodiode, a 40-nm thick film of poly(3, 4-ethylendioxytbiophene):poly(styrensulfonate) (PE- DOT:PSS) is primarily deposited on a cleaned ITO coated glass substrate by spin coating technique. The organic photo- sensitive blend is later spun coated on the PEDOT:PSS layer, followed by the lithium fluoride (LiF) and aluminium (A1) thin films deposition by thermal evaporation. The optical properties of the MEH-PPV:Alq3 blend thin films are investigated using photoluminescence (PL) and UV-Vis spectroscopy. The photodiode shows good photo-current response as a function of variable illumination levels. The responsivity value - 8 mA/W at 3 V is found and the ratio of photo-current to dark current (lph/IDark) is found to be 1.24. 相似文献
204.
Amruthotharam kashayam is an important Ayurvedic formulation prepared using specified plant parts of Tinospora cordifolia, Terminalia chebula, and Zingiber officinale. The current study developed a rapid liquid chromatographic method coupled with electro spray ionization mass spectrometry for the identification of major phytoconstituents present in the formulation. Reverse phase high-pressure liquid chromatogram was developed as chemical fingerprint. The mass spectrum along with the MS/MS fragmentation on collision-induced dissociation led to the structural identification of separated compounds. Phenolic acids such as quinic acid, protocatechuic acid, gallic acid, and chebulic acid were identified in the formulation along with some flavonoids. 相似文献
205.
Diffusion tensor magnetic resonance imaging (DTI) is useful for studying the microstructural changes in the spinal cord following traumatic injury; however, image quality is generally poor due to the small size of the spinal cord, physiological motion and susceptibility artifacts. Self-navigated, interleaved, variable-density spiral diffusion tensor imaging (SNAILS-DTI) is a distinctive pulse sequence that bypasses many of the challenges associated with DTI of the spinal cord, particularly if imaging gradient hardware is of conventional quality. In the current study, we have demonstrated the feasibility of implementing SNAILS-DTI on a clinical 3.0-T MR scanner and examined the effect of navigator filter parameters on image quality and reconstruction time. Results demonstrate high-quality, high-resolution (546 μm×546 μm) in vivo DTI images of the cat spinal cord after traumatic spinal cord injury. 相似文献
206.
LiSn2P3O12 with sodium (Na) super ionic conductor (NASICON)-type rhombohedral structure was successfully obtained at low sintering temperature, 600 °C via citric acid-assisted sol-gel method. However, when the sintering temperature increased to 650 °C, triclinic structure coexisted with the rhombohedral structure as confirmed by X-ray diffraction analysis. Conductivity–temperature dependence of all samples were studied using impedance spectroscopy in the temperature range 30 to 500 °C, and bulk, grain boundary and total conductivity increased as the temperature increased. The highest bulk conductivity found was 3.64?×?10?5 S/cm at 500 °C for LiSn2P3O12 sample sintered at 650 °C, and the lowest bulk activation energy at low temperature was 0.008 eV, showing that sintering temperature affect the conductivity value. The voltage stability window for LiSn2P3O12 sample sintered at 600 °C at ambient temperature was up to 4.4 V. These results indicated the suitability of the LiSn2P3O12 to be exploiting further for potential applications as solid electrolytes in electrochemical devices. 相似文献
207.
We study the partitions of a graph G with vertices labeled 1,2,…,n. A matrix notation for partitions is devised which reflects a partial order among partitions and provides a matrix characterization (in terms of the adjacency matrix A of G) of a coloration or equitable partition. An especially useful partition is one based on the number of walks issuing from each vertex. This is not generally a coloration (sufficient conditions are given) but nevertheless plays a special role relative to colorations. The spectrum of G, Sp(G), has a “main part”, the set of eigenvalues with an eigenvector not orthogonal to e (the column of 1s). We disprove a conjecture of Harary and Schwenk about the main part of the spectrum and prove an alternate characterization. The walk partition appears here and also in a relation between the main parts of the spectra of G and ?, its complement. 相似文献
208.
Sudha Srinivas S.B. Sulaiman N. Sahoo T.P. Das E. Torikai K. Nishiyama K. Nagamine 《Hyperfine Interactions》1997,107(1-4):167-173
The reaction mechanism of excitation and de-excitation of the high-spin isomers 180Hf (J=8-) and 180Ta (J=9-) in inelastic gamma-quanta scattering was investigated. An anomalously large integral cross section and isomeric ratio for
180Ta in comparison to 180Hf were obtained. Level properties influencing these relations are discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
209.
Suresha N. Deveshegowda Prashant K. Metri Rashmi Shivakumar Ji-Rui Yang Shobith Rangappa Ananda Swamynayaka Muthu K. Shanmugam Omantheswara Nagaraja Mahendra Madegowda Priya Babu Shubha Arunachalam Chinnathambi Sulaiman Ali Alharbi Vijay Pandey Kwang Seok Ahn Peter E. Lobie Basappa Basappa 《Molecules (Basel, Switzerland)》2022,27(9)
A number of uracil amides cleave poly (ADP-ribose) polymerase and therefore novel thiouracil amide compounds were synthesized and screened for the loss of cell viability in a human-estrogen-receptor-positive breast cancer cell line. The synthesized compounds exhibited moderate to significant efficacy against human breast cancer cells, where the compound 5e IC50 value was found to be 18 μM. Thouracil amide compounds 5a and 5e inhibited the catalytical activity of PARP1, enhanced cleavage of PARP1, enhanced phosphorylation of H2AX, and increased CASPASE 3/7 activity. Finally, in silico analysis demonstrated that compound 5e interacted with PARP1. Hence, specific thiouracil amides may serve as new drug-seeds for the development of PARP inhibitors for use in oncology. 相似文献
210.
Tukur Abdulkadir Sulaiman Hasan Bulut Gulnur Yel Sibel Sehriban Atas 《Optical and Quantum Electronics》2018,50(10):372
This study reaches the dark, bright, mixed dark-bright, singular, mixed singular optical solitons and singular periodic wave solutions to the time-fractional Radhakrishnan–Kundu–Lakshmanan equation. The parametric conditions that guarantee the existence of valid solitons and other solutions are stated. By choosing some suitable values of parameters, the 2- and 3-dimensional surfaces to some of the reported solutions are plotted. The reported solutions may be useful in expalining the physical meaning of the Radhakrishnan–Kundu–Lakshmanan equation and other related nonlinear models arising in nonlinear sciences. 相似文献