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A Nawaz H Matta R Shawis A Jazcobsz S Kassir AH Al-Salem 《Canadian Metallurgical Quarterly》1998,14(3):214-217
Randomized, prospective trials examining the effectiveness of carotid endarterectomy have given distinct information into the mechanisms and prevention of embolic strokes. The North American Symptomatic Carotid Endarterectomy Trial (NASCET) and the Asymptomatic Carotid Atherosclerosis Study (ACAS) have demonstrated the benefits of carotid endarterectomy for patients who meet the precise selection criteria and are treated according to established study protocols. The existing challenge to clinicians lies in the application of trial results to the individual patient. 相似文献
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Zeeshan Nawaz Xiaoping Tang Qiang Zhang Dezheng Wang Wei Fei 《Catalysis communications》2009,10(14):1925-1930
The Pt–Sn-based catalyst was intensified using SAPO-34 as support for direct propane dehydrogenation to propylene. The catalyst was prepared by sequential impregnation method and characterized by XRF, BET, XRD, NH3-IR, NH3-TPD, H2-TPR, HR-TEM and O2-pulse coke analysis. NH3-TPD, IR spectra and XRD results suggested that the doping of metals on SAPO-34 did not affect its acidic strength and structural topology of support, respectively. Propylene selectivity of 94% and total olefins selectivity greater than 97% was achieved using Pt–Sn/SAPO-34. The results were compared with Pt–Sn/ZSM-5 under identical conditions. The possible reasons for improvement were the larger surface area, shape selectivity and particular by suitable acidity of SAPO-34. 相似文献
35.
Using full 3D TCAD, an evaluation of process parameter space of bulk FinFET is presented from the point of view of DRAM, SRAM and I/O applications. Process and device simulations are performed with varying uniform fin doping, anti-punch implant dose and energy, fin width, fin height and gate oxide thickness. Bulk FinFET architecture with anti-punch implant is introduced beneath the channel region to reduce the punch-through and junction leakage. For 30 nm bulk FinFET, anti-punch implant with low energy of 15 to 25 keV and dose of 5.0 × 1013 to 1.0 × 1014 cm−2 is beneficial to effectively suppress the punch-through leakage with reduced GIDL and short channel effects. Our simulations show that bulk FinFETs are approximately independent of back bias effect. With identical fin geometry, bulk FinFETs with anti-punch implant show same ION-IOFF behavior and approximately equal short channel effects like SOI FinFETs. 相似文献
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Bukhari Muhammad Adnan Ahmad Zahoor Ashraf M. Yasin Afzal Muhammad Nawaz Fahim Nafees Muhammad Jatoi Wajid Nasim Malghani Naveed Aslam Shah Adnan Noor Manan Abdul 《SILICON》2021,13(12):4757-4772
Silicon - Feeling prone to stress differs with plant production stage, water scarcity near commencement of grain filling phase has a significant reduced grain yield through fewer endosperm and sink... 相似文献
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JAVARIA AFZAL XIUKANG WANG MUHAMMAD HAMZAH SALEEM XUECHENG SUN SHAHID HUSSAIN IMRAN KHAN MUHAMMAD SHOAIB RANA SHAKEEL AHMED SAMRAH AFZAL AWAN SAJID FIAZ OMAR AZIZ KASHIF ALI KUBAR SHAFAQAT ALI CHENGXIAO HU 《Biocell》2021,45(6):1631-1649
Soil contamination with toxic heavy metals [such as cadmium (Cd)] is becoming a serious global problem due
to rapid development of social economy. Iron (Fe), being an important element, has been found effective in enhancing
plant tolerance against biotic and abiotic stresses. The present study investigated the extent to which different levels of
Ferrous sulphate (FeSO4) modulated the Cd tolerance of rice (Oryza sativa L.), when maintained in artificially Cd
spiked regimes. A pot experiment was conducted under controlled conditions for 146 days, by using natural soil,
mixed with different levels of CdCl2 [0 (no Cd), 0.5 and 1 mg/kg] together with the exogenous application of FeSO4
at [0 (no Fe), 1.5 and 3 mg/kg] levels to monitor different growth, gaseous exchange characteristics, oxidative stress,
antioxidative responses, minerals accumulation, organic acid exudation patterns of O. sativa. Our results depicted that
addition of Cd to the soil significantly (P < 0.05) decreased plant growth and biomass, gaseous exchange parameters,
mineral uptake by the plants, sugars (soluble, reducing, and non-reducing sugar) and altered the ultrastructure of
chloroplasts, plastoglobuli, mitochondria, and many other cellular organelles in Cd-stressed O. sativa compared to
those plants which were grown without the addition of Cd in the soil. However, Cd toxicity boosted the production of
reactive oxygen species (ROS) by increasing the contents of malondialdehyde (MDA), which is the indication of
oxidative stress in O. sativa and was also manifested by hydrogen peroxide (H2O2) contents and electrolyte leakage to
the membrane bounded organelles. Although, activities of various antioxidative enzymes like superoxidase dismutase
(SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) and non-enzymatic antioxidants like
phenolics, flavonoid, ascorbic acid, anthocyanin and proline contents increased up to a Cd level of 0.5 mg/kg in the
soil but were significantly diminished at the highest Cd level of 1 mg/kg in the soil compared to those plants which
were grown without the addition of Cd in the soil. The negative impacts of Cd injury were reduced by the application
of FeSO4 which increased plant growth and biomass, improved photosynthetic apparatus, antioxidant enzymes, minerals uptake together with diminished exudation of organic acids as well as oxidative stress indicators in roots and
shoots of O. sativa by decreasing Cd retention in different plant parts. These results shed light on the effectiveness of
FeSO4 in improving the growth and upregulation of antioxidant enzyme activities of O. sativa in response to Cd
stress. However, further studies at field levels are required to explore the mechanisms of FeSO4-mediated reduction of
the toxicity of not only Cd, but possibly also other heavy metals in plants. 相似文献
39.
Ali Farman Ali Zulfiqar Li Bing-Zhao Qamar Sadia Nazeer Amna Riaz Saba Khan Muhammad Asif Fayyaz Rabia Nawaz Abbasi Javeria 《Water Resources Management》2022,36(9):2989-3005
Water Resources Management - Drought is recurrently occurring in many parts of the globe. In contrast to other natural hazards, drought has complex climatic characteristics. Several environmental... 相似文献
40.