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101.
The direct catalytic dehydrogenation of propane to propene is an important route to enhance propene production. In the present
experimentation the focus was to investigate the influence of incipient operating conditions, Si/Al ratio of zeolite support
and effect of zinc doping on Pt-Sn/ZSM-5 catalyst performance. The catalysts were extensively investigated by reaction tests
in a continuous plug-flow quartz micro-reactor. The experimental data shows that the manipulation of operating parameters
significantly improves the reaction performance, while huge dynamicity is observed in product distribution. Reaction temperature,
600 °C is found to be most suitable, while increasing the weight hourly space velocity (WHSV), propene selectivity improves
at the expense of lower conversion. The OPE was drawn to observe overall reaction network. It was found that the acidity of
zeolitic support plays a more important role in achieving desired product selectivity than additional metallic content. Accordingly,
the Si/Al ratio of the ZSM-5 zeolite the pro- pene selectivity was enhanced, leading to remarkable improvement in the total
olefins selectivity which was remarkably improved owing to a suppression of secondary reactions. At Si/Al ratio 300, the selectivity
of propene and total olefins becomes stable at 73% and 90% respectively. The doping of Zn on Pt-Sn/ZSM-5 improves only propene
selectivity, but is severely affected by quick deactivation. 相似文献
102.
B Hussain M Ahmed M Nawaz M Saleem M Razzaq M Aslam Zia M Iqbal 《Applied optics》2012,51(21):5326-5330
We present a simple technique for simultaneous determination of thickness and refractive index of plane-parallel samples in the terahertz radiation domain. The technique uses time-of-flight measurements of the terahertz pulse. It has been employed on nine different polymers and semiconductor materials, which are transparent for terahertz frequencies. Our results of thickness measurement are in good agreement with micrometer reading. The accuracy in the determination of refractive index is on the order of two decimal points. 相似文献
103.
Mohammed Ibrahim Shukoor Filipe Natalio Muhammad Nawaz Tahir Matthias Wiens Marco Tarantola Helen Annal Therese Matthias Barz Stefan Weber Maxim Terekhov Heinz C. Schröder Werner E. G. Müller Andreas Janshoff Patrick Theato Rudolf Zentel Laura Maria Schreiber Wolfgang Tremel 《Advanced functional materials》2009,19(23):3717-3725
Here, design of the first pathogen‐mimicking metal oxide nanoparticles with the ability to enter cancer cells and to selectively target and activate the TLR9 pathway, and with optical and MR imaging capabilities, is reported. The immobilization of ssDNA (CpG ODN 2006) on MnO nanoparticles is performed via the phosphoramidite route using a multifunctional polymer. The multifunctional polymer used for the nanoparticle surface modification not only affords a protective organic biocompatible shell but also provides an efficient and convenient means for loading immunostimulatory oligonucleotides. Since fluorescent molecules are amenable to photodetection, a chromophore (Rhodamine) is introduced into the polymer chain to trace the nanoparticles in Caki‐1 (human kidney cancer) cells. The ssDNA coupled nanoparticles are used to target Toll‐like receptors 9 (TLR9) receptors inside the cells and to activate the classical TLR cascade. The presence of TLR9 is demonstrated independently in the Caki‐1 cell line by western blotting and immunostaining techniques. The magnetic properties of the MnO core make functionalized MnO nanoparticles potential diagnostic agents for magnetic resonance imaging (MRI) thereby enabling multimodal detection by a combination of MR and optical imaging methods. The trimodal nanoparticles allow the imaging of cellular trafficking by different means and simultaneously are an effective drug carrier system. 相似文献
104.
Silicon - By using laboratory developed agglomerated basic fluxes a study has been carried out to predict the element transfer across the series of bead on plate weld deposits in submerged arc... 相似文献
105.
106.
107.
Raza Ali Nawaz Syed Junaid Ahmed Abrar Wyne Shurjeel Muhammad Bilal Patwary Mohmammad N. Prasad Ramjee 《Wireless Personal Communications》2022,122(4):3545-3571
Wireless Personal Communications - Non-orthogonal multiple access (NOMA) scheme, potentially enabling high spectral efficiency, is one of the key technological innovations in the 5th generation... 相似文献
108.
Wireless Personal Communications - The small cell technology is considered as a key technology for 5G networks. The capacity expansion and coverage extension are both achieved through this... 相似文献
109.
110.
Muhammad Maqbool Qaisar Nawaz Muhammad Atiq Ur Rehman Mark Cresswell Phil Jackson Katrin Hurle Rainer Detsch Wolfgang H. Goldmann Asma Tufail Shah Aldo R. Boccaccini 《International journal of molecular sciences》2021,22(8)
In this study, as a measure to enhance the antimicrobial activity of biomaterials, the selenium ions have been substituted into hydroxyapatite (HA) at different concentration levels. To balance the potential cytotoxic effects of selenite ions (SeO32−) in HA, strontium (Sr2+) was co-substituted at the same concentration. Selenium and strontium-substituted hydroxyapatites (Se-Sr-HA) at equal molar ratios of x Se/(Se + P) and x Sr/(Sr + Ca) at (x = 0, 0.01, 0.03, 0.05, 0.1, and 0.2) were synthesized via the wet precipitation route and sintered at 900 °C. The effect of the two-ion concentration on morphology, surface charge, composition, antibacterial ability, and cell viability were studied. X-ray diffraction verified the phase purity and confirmed the substitution of selenium and strontium ions. Acellular in vitro bioactivity tests revealed that Se-Sr-HA was highly bioactive compared to pure HA. Se-Sr-HA samples showed excellent antibacterial activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus carnosus) bacterial strains. In vitro cell–material interaction, using human osteosarcoma cells MG-63 studied by WST-8 assay, showed that Se-HA has a cytotoxic effect; however, the co-substitution of strontium in Se-HA offsets the negative impact of selenium and enhanced the biological properties of HA. Hence, the prepared samples are a suitable choice for antibacterial coatings and bone filler applications. 相似文献