|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Simultaneous operation of dibenzothiophene hydrodesulfurization and methanol reforming reactions over Pd promoted alumina based catalysts显示文摘In the current study simultaneous reactions of hydrodesulfurization(HDS) of dibenzothiophene(DBT) and reforming of methanol in a micro-autoclave reactor were studied over bi-metallic(Co-Mo/Al2O3 and Ni-Mo/Al2O3) and tri-metallic(Pd-Co-Mo/Al2O3 and Pd-Ni-Mo/Al2O3) catalyst systems which were prepared by incipient impregnation method.In situ hydrogen utilization and low Pd loadings were the major targets of this study.For comparison purpose,catalytic activity was separately determined for both the methanol reforming and HDS of DBT reactions as well.Ni based catalysts were confirmed with better activity than Co ones for both the reactions with Pd promoted ones ranking at the top i.e.Pd-Ni-Mo/Al2O3 > Ni-Mo/Al2O3 > Pd-Co-Mo/Al2O3 > Co-Mo/Al2O3 where Pd-Ni-Mo/Al2O3 showed 91% DBT conversion at 380 ℃ and 12 h reaction time.Some of the selected organic additives on catalytic activity were tested for their effect toward HDS reaction which was unique with close relation to their chemical nature.Reaction products were quantitatively and qualitatively analyzed via HPLC and GC-MS techniques respectively which helped in elucidating reaction mechanism. | Muhammad Yaseen Muhammad Shakimllah Imtiaz Ahmad Ata Ur Rahman Faiz Ur Rahman Muhammad Usman Rauf Razzaq | 2012 | 燃料化学学报2012，40，6： | 3 |
| 2 | Oxidative desulfurization of dibenzothiophene over Fe promoted Co–Mo/Al_2O_3 and Ni–Mo/Al_2O_3 catalysts using hydrogen peroxide and formic acid as oxidants显示文摘This work reports the enhancing effect of a highly cost effective and efficient metal, Fe, incorporation to Co or Ni based Mo/Al_2O_3 catalysts in the oxidative desulfurization(ODS) of dibenzothiophene(DBT) using H_2O_2 and formic acid as oxidants. The influence of operating parameters i.e. reaction time, catalyst dose, reaction temperature and oxidant amount on oxidation process was investigated. Results revealed that 99% DBT conversion was achieved at 60 °C and 150 min reaction time over Fe–Ni–Mo/Al_2O_3. Fe tremendously enhanced the ODS activity of Co or Ni based Mo/Al_2O_3 catalysts following the activity order: Fe–Ni–Mo/Al_2O_3 NFe–Co–Mo/Al_2O_3 NNi–Mo/Al_2O_3 NCo–Mo/Al_2O_3, while H_2O_2 exhibited higher oxidation activity than formic acid over all catalyst systems. Insight about the surface morphology and textural properties of fresh and spent catalysts were achieved using scanning electron microscopy(SEM), X-ray diffraction(XRD), energy dispersive X-ray(EDX)analysis, Atomic Absorption Spectroscopy(AAS) and BET surface area analysis, which helped in the interpretation of experimental data. The present study can be deemed as an effective approach on industrial level for ODS of fuel oils crediting to its high efficiency, low process/catalyst cost, safety and mild operating condition. | Yaseen Muhammad Ayesha Shoukat Ata Ur Rahman Haroon Ur Rashid Waqas Ahmad | 2018 | Chinese Journal of Chemical Engineering2018，26，3： | 3 |
| 3 | Effect of Zn doping on electronic structure and optical properties zincblende GaN(A DFT+U insight)显示文摘The development of new materials,having exceptional properties in comparison to existing materials is highly required for bringing advancement in electronic and optoelectronic technologies.Keeping this fact,we investigated structural,electronic,and optical properties of zincblende GaN doped with selected Zn concentrations(6.25%,12.50%,and 18.70%),using the first-principle calculations based on density functional theory with GGA+U.We conducted the entire study using the WIEN2K code.In this study,we calculated various significant parametric quantities such as cohesive energies,formation energies,bulk moduli,and lattice constants along with the study of optical and electronic properties by substituting Ga atoms with Zn atoms in 1×2×2 supercell.The structural stability is confirmed by studying the phonon dispersion curves which suggest that Zn:GaN material is stable against the 6.25%and 18.70%Zn concentrations while for 12.50%,it shows instability.The Hubbard values U=0,2,4,6 eV were added to GGA and the electronic properties were improved with the U=6 eV.Optical absorption was blue shifted while the refractive index and dielectric constant were increased with increasing the Zn concentrations.Electronic properties are enhanced due to the prime contribution of cations(Zn)3ri states.The optical and electronic properties are further discussed in detail in the entire study. | Muhammad Junaid Iqbal Khan Zarfishan Kanwal Masood Yousaf Hamid Ullah Javed Ahmad Abid Latif Yong-Han Shin Ata Ur Rahman Khalid | 2021 | Communications in Theoretical Physics2021，73，3： | 1 |
| 4 | 超吸水中国粘土/聚丙烯酸复合材料的制备与表征(英文)显示文摘本文采用共聚合法,以过硫酸钾作为发剂,N-N-亚甲基双丙烯酰胺作为交联剂,亚硫酸钠作为催化剂,合成了不同组成的SAPC样品系列.对比不同样品,找出中国粘土含量和丙烯酸含量对吸水和保水能力的影响.与原始粘土相比,中国粘土在SAPC中的层间距离有所扩大.SAPC中粘土含量对吸水性的影响表明,在45%含量以下,水的吸收率随粘土含量的增加而增加,而粘土含量的进一步增加降低了水的吸收性.在不同丙烯酸重量百分比样品中,最佳吸收率在丙烯酸重量百分比25%∽35%之间.所得聚合物复合材料具有约190g/g的高吸水性. | Tanveer-Ul-Hassan Shah Mudassir Hussain Tahir Ata ur Rahman 刘和文 | 2019 | Chinese Journal of Chemical Physics2019，32，4： | 1 |
| 5 | Tunable beam deflection based on plasmonic resonators mounted freestanding thermoresponsive hydrogel显示文摘We propose and numerically demonstrate a dynamic beam deflector based on plasmonic resonator loaded thermoresponsive freestanding hydrogel that swells and collapses in water by temperature.For this purpose,we utilize four-step phase gradients mounted on freestanding hydrated hydrogel.For normal incidence,linearly orthogonal light deflects to 19.44°in the collapsed state and 14.40°in the swollen state of hydrogel.Furthermore,the light deflects at a third angle of 12.29°when the solvent changes from water to ethanol.It is expected that our metadesign will provide a platform for dynamic holography,active lensing,data storage,and anticounterfeiting. | Ata Ur Rahman Khalid 刘娟 Naeem Ullah 贾世琪 | 2020 | Chinese Optics Letters2020，18，6： | 0 |
| 6 | Single-layered non-interleaved spin-insensitive metasurfaces for wavefront engineering显示文摘Metasurfaces,two-dimensional(2D)or quasi-2D arrays of dielectric or metallic meta-atoms,offer a compact and novel platform to manipulate the amplitude,phase,and polarization of incoming wavefronts in a desired manner by engineering the geometry of meta-atoms.In polarization control,spin-insensitive metasurfaces have attracted significant attention due to the robustness of circular polarization against the beam misalignment and multi-path effects.Till now,several efforts have been made to realize polarization-insensitive metasurfaces for circularly polarized(CP)wavefront manipulation;however,these metasurfaces only consider the cross-polarization channels and keep the co-polarization channels abandoned.Such metasurfaces cannot be considered truly spin-insensitive,as one has to carefully choose the analyzer at output.Here,by combining the polarization-insensitive geometric phase and engineered propagation phase,we propose a spin-insensitive design principle based on metasurfaces that can perform identical functionality(on co-and crosspolarization channels)irrespective of the handedness of incident/transmitted light.As a proof of concept,we design and numerically realize two types of spin-insensitive wavefront engineering devices:(1)spin-insensitive meta-hologram and(2)spin-insensitive beam deflector with power splitting functionality.The proposed work is expected to open up new avenues for developing spin-independent metasurfaces-based devices. | Ata Ur Rahman Khalid Naeem Ullah 韩遇 Urooj Asghar 袁小聪 冯甫 | 2023 | Chinese Optics Letters2023，21，1： | 0 |
| 7 | Exploitation of geometric and propagation phases for spin-dependent rational-multiple complete phase modulation using dielectric metasurfaces显示文摘Metasurfaces have drawn considerable attention in manipulation of electromagnetic waves due to their exotic subwavelength footprints. Regardless of immense progress of polarization-dependent flat optics, the realization of on-device switchable complete phase multiplication is still missing from design multifunctional devices. Here,by combining geometric and propagation phases, a generalized design principle is proposed that can achieve switchable integer or fractional multiple complete phase modulation in transmitted circularly cross-polarized light by switching the handedness of incident polarization. As a proof of concept, two types of spin-dependent bifunctional wavefront manipulating devices, including switchable beam splitter/beam deflector and spinto-orbital angular momentum converter designs are numerically realized. It is believed that the proposed single-cell spin-switchable rational-multiple complete-phase-modulation design principle based on combined propagation and geometric phases has great potential to underpin the development of meta-optics-based multifunctional operations in the field of integrated optics, imaging, and optical communication. | Ata Ur Rahman Khalid Fu FENG Naeem Ullah Xiaocong Yuan Michael Geoffrey Somekh | 2022 | Photonics Research2022，10，4： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员