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671.
C. R. Liu J. F. Zhao X. Y. Lu Q. S. Meng Y. P. Zhao Z. A. Munir 《Journal of Materials Science》2008,43(15):5076-5082
The bonding of glass wafers to aluminum foils in multi-layer assemblies was investigated by the field-assisted diffusion bonding
process. Bonding was effected at temperatures in the range 350–450 °C and with an applied voltage in the range 400–700 V under
a pressure of 0.05 MPa. The experimental parameters of voltage and temperature were the main factors in influencing the ionic
current leading to the formation of the depleted layer. The peak current in three-layer samples (glass/aluminum/glass) during
bonding is twice that for the case of the two-layer samples (aluminum/glass). SEM and EDS analyses showed the presence of
transition layers near the glass/aluminum interface, and XRD data demonstrated the phase structure of the glass/aluminum interface.
The tensile strength of the bonded material increased markedly with increasing temperature and applied voltage. Fracture occurred
in the glass phase near the interface with the aluminum. Finite element analysis showed the residual deformation in three-layer
samples to be significantly lower than in two-layer samples. The symmetry in three-layer samples resulted in the absence of
strain, an important advantage in MEMS fabrication. 相似文献
672.
Aftab Hussain 忻向军 Abdul Latif Ashiq Hussain 余重秀 Abid Munir Yousaf Khan Muhammad Idrees Afridi 《光电子快报》2012,8(6):468-472
We propose the single feeder fiber architecture for wavelength division multiplexing passive optical network(WDM-PON)based on directly modulated chirp managed laser(CML).The downlink(DL)signal output from the laser is converted to return-to-zero(RZ)differential phase shift signal using a pulse carver.The downstream signal is reused as a carrier for the upstream using intensity modulation technique.Simulation results show the error-free performance at symmetric data rate of 10 Gbit/s per channel with negligible power penalty and improved receiver sensitivity for the uplink(UL),over 25 km standard single-mode fiber(SSMF).A low-cost and reduced circuitry network design is implemented on a single feeder fiber with the elimination of differential encoder and one external modulator. 相似文献
673.
This work investigates the relevance of several factors affecting the response of silicon diode dosemeters in depth-dose scans of electron beams. These factors are electron energy, instantaneous dose rate, dose per pulse, photon/electron dose ratio and electron scattering angle (directional response). Data from the literature and our own experiments indicate that the impact of these factors may be up to +/-15%. Thus, the different factors would have to cancel out perfectly at all depths in order to produce true depth-dose curves. There are reports of good agreement between depth-doses measured with diodes and ionisation chambers. However, our measurements with a Scantronix electron field detector (EFD) diode and with a plane-parallel ionisation chamber show discrepancies both in the build-up and in the low-dose regions, with a ratio up to 1.4. Moreover, the absolute sensitivity of two diodes of the same EFD model was found to differ by a factor of 3, and this ratio was not constant but changed with depth between 5 and 15% in the low-dose regions of some clinical electron beams. Owing to these inhomogeneities among diodes even of the same model, corrections for each factor would have to be diode-specific and beam-specific. All these corrections would have to be determined using parallel plane chambers, as recommended by AAPM TG-25, which would be unrealistic in clinical practice. Our conclusion is that in general diodes are not reliable in the measurement of depth-dose curves of clinical electron beams. 相似文献
674.
The preparation of functionally graded materials (FGMs) of (TiB2)pNi with an intermetallic compound media layer of Ni3Al and a substrate of nickel by field-activated pressure-assisted synthesis process (FAPAS) was investigated. Ni3Al was chosen as a layer of FGM for the first time due to its great deal of heat released during its synthesis from nickel
and aluminium powder. The microstructure, phase composition of layers, micro-hardness and elemental concentration profiles
across interfaces were characterized. The significant inter-diffusion of elements between layers showed the formation of good
bonds. The measured micro-hardness values of the sample increased monotonically to more than 3 500 HK over a distance of 2
mm from the nickel substrate to the surface layer (TiB2)pNi. The results of this investigation demonstrate the feasibility of the FAPAS process for rapid formation of FGMs with good
diffusion bonds. 相似文献
675.
Amjad Rehman Naveed Abbas Tanzila Saba Toqeer Mahmood Hoshang Kolivand 《Microscopy research and technique》2018,81(7):737-744
Splitting the rouleaux RBCs from single RBCs and its further subdivision is a challenging area in computer‐assisted diagnosis of blood. This phenomenon is applied in complete blood count, anemia, leukemia, and malaria tests. Several automated techniques are reported in the state of art for this task but face either under or over splitting problems. The current research presents a novel approach to split Rouleaux red blood cells (chains of RBCs) precisely, which are frequently observed in the thin blood smear images. Accordingly, this research address the rouleaux splitting problem in a realistic, efficient and automated way by considering the distance transform and local maxima of the rouleaux RBCs. Rouleaux RBCs are splitted by taking their local maxima as the centres to draw circles by mid‐point circle algorithm. The resulting circles are further mapped with single RBC in Rouleaux to preserve its original shape. The results of the proposed approach on standard data set are presented and analyzed statistically by achieving an average recall of 0.059, an average precision of 0.067 and F‐measure 0.063 are achieved through ground truth with visual inspection. 相似文献
676.
Tanzila Saba Sana Ullah Khan Naveed Islam Naveed Abbas Amjad Rehman Nadeem Javaid Adeel Anjum 《Microscopy research and technique》2019,82(6):775-785
The advancement of computer‐ and internet‐based technologies has transformed the nature of services in healthcare by using mobile devices in conjunction with cloud computing. The classical phenomenon of patient–doctor diagnostics is extended to a more robust advanced concept of E‐health, where remote online/offline treatment and diagnostics can be performed. In this article, we propose a framework which incorporates a cloud‐based decision support system for the detection and classification of malignant cells in breast cancer, while using breast cytology images. In the proposed approach, shape‐based features are used for the detection of tumor cells. Furthermore, these features are used for the classification of cells into malignant and benign categories using Naive Bayesian and Artificial Neural Network. Moreover, an important phase addressed in the proposed framework is the grading of the affected cells, which could help in grade level necessary medical procedures for patients during the diagnostic process. For demonstrating the e effectiveness of the proposed approach, experiments are performed on real data sets comprising of patients data, which has been collected from the pathology department of Lady Reading Hospital of Pakistan. Moreover, a cross‐validation technique has been performed for the evaluation of the classification accuracy, which shows performance accuracy of 98% as compared to physical methods used by a pathologist for the detection and classification of the malignant cell. Experimental results show that the proposed approach has significantly improved the detection and classification of the malignant cells in breast cytology images. 相似文献
677.
Arshad Jamal Mohammed Hazim Alkawaz Amjad Rehman Tanzila Saba 《Microscopy research and technique》2017,80(7):799-811
With an increase in the advancement of digital imaging and computing power, computationally intelligent technologies are in high demand to be used in ophthalmology cure and treatment. In current research, Retina Image Analysis (RIA) is developed for optometrist at Eye Care Center in Management and Science University. This research aims to analyze the retina through vessel detection. The RIA assists in the analysis of the retinal images and specialists are served with various options like saving, processing and analyzing retinal images through its advanced interface layout. Additionally, RIA assists in the selection process of vessel segment; processing these vessels by calculating its diameter, standard deviation, length, and displaying detected vessel on the retina. The Agile Unified Process is adopted as the methodology in developing this research. To conclude, Retina Image Analysis might help the optometrist to get better understanding in analyzing the patient's retina. Finally, the Retina Image Analysis procedure is developed using MATLAB (R2011b). Promising results are attained that are comparable in the state of art. 相似文献
678.
Firdaus Muhammad-Sukki Abu Bakar Munir Roberto Ramirez-Iniguez Siti Hawa Abu-Bakar Siti Hajar Mohd Yasin Scott G. McMeekin Brian G. Stewart 《Renewable & Sustainable Energy Reviews》2012,16(7):5232-5244
This paper examines solar photovoltaic (PV) in Malaysia. First, it analyzes the current energy demand in Malaysia and discusses some of the national policies and the installations of solar PV in urban and rural areas in the country. Next, the general Feed-In Tariff (FiT) scheme is explained, indicating its potential as one of the investment options for Malaysians. Finally, the loan financing option for solar PV is presented, providing examples that have been implemented in other countries, as well as explaining the Green Technology Financing Scheme (GTFS) for companies and the proposed soft loan scheme for individual households in Malaysia. It also analyses the impact of the proposed interest rate to household consumers in Malaysia, in terms of total profit, net present value and internal rate of return. It is found that the FiT scheme could potentially help in increasing renewable energy penetration, particularly for solar PV. To provide upfront capital for solar PV installation, it is shown that the GTFS is a good financial source for companies while for individual home owners, a soft loan facility from banking institutions is a feasible source if the interest rate is 5% or less. 相似文献
679.
Dr. Muhammad Imran Tousif Dr. Mamona Nazir Prof. Dr. Naheed Riaz Prof. Dr. Muhammad Saleem Saba Tauseef Sheikh Muhammad Azam Prof. Dr. Mirza Arfan Yawer Prof. Dr. Gokhan Zengin 《Chembiochem : a European journal of chemical biology》2023,24(22):e202300346
Human neutrophil elastase (HNE) is an enzyme that plays a key role in the body‘s inflammatory response. It has been linked to several diseases such as chronic obstructive pulmonary disease (COPD), emphysema, and cystic fibrosis. As potential treatments for these diseases, HNE inhibitors are of great interest. Metabolites derived from plants, particularly terpenoids such as β-caryophyllene found in black pepper and other plants, and geraniol present in several essential oils, are recognized as significant sources of inhibitors for HNE. Because of their ability to inhibit HNE, terpenoids are considered promising candidates for developing novel therapies to treat inflammatory conditions such as COPD and emphysema. Furthermore, nature can serve as an excellent designer, and it may offer a safer drug candidate for inhibiting HNE production and activity in the future. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were searched to get relevant and up-to-date literature on terpenoids as human neutrophil elastase inhibitors. This review focuses on the isolation, chemical diversity, and inhibition of human neutrophil elastase (HNE) of various terpenoids reported from natural sources up to 2022. A total of 251 compounds from various terpenoids classes have been reported. Further, it also provides a summary of HNE inhibitors and includes a thorough discussion on the structure-activity relationship. 相似文献
680.
Haq Nawaz Nadia Zafar Raheela Jabeen Adnan Amjad Mohibullah Shah Saba Munir 《European Journal of Lipid Science and Technology》2023,125(11):2300053
The repeated use of cooking oils and ghee for the deep frying of food materials may affect their nutritional quality. The present study evaluated the effect of repeated frying on the physicochemical characteristics and antiradical potential of canola oil and ghee. The oil and ghee were used for frying of fish and chicken for 2, 4, 6, 8, and 10 frying cycles followed by the analysis of physicochemical, oxidative stress, and antiradical parameters. Regression analysis of the data showed a frying cycle-dependent significant linear increase in saponification (R2 = 0.9507–0.9748), peroxide and acid values (R2 = 0.956–0.9915), and malondialdehyde (MDA) production (R2 = 0.9058–0.9557) of canola oil and ghee subjected to fish and chicken frying but exponential increase in saponification value (R2 = 0.9778) and MDA production (R2 = 0.7407) of canola oil and ghee used for fish frying. The increase in the number of frying cycles linearly decreased the iodine value (R2 = 0.9781–0.9924), and 1, 1-diphenyl-2-picrylhydrazyl, hydroxyl, and 2, 2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical scavenging potential (R2 = 0.9089–0.9979) of canola oil and ghee. Repeated frying in cooking oil and ghee increases oxidative stress and decreases their physicochemical and antioxidant qualities. Canola oil was comparatively more oxidative resistant than canola ghee. The regression equations derived from regression analysis will guide researchers to conduct similar types of univariate studies. 相似文献