Propagation characteristics of the ten-parameter family of partially coherent general anisotropic gaussian schellmodel (AGSM) beams passing through first-order optical system

Abstract

Based on the closed property of AGSM beams under the action of first-order optical systems, the explicit transformation and twist expressions for the principal axes of intensity distribution, transverse coherence distribution and the principal curvatures of phase front in the cross-spectral density function of AGSM beams are derived. For typical applications, for AGSM beams passing through free space, the twist and variation regularities of the principal axes and the principal curvatures are analysed in detail. The twist-free conditions are discussed and the twist influenced by the physical parameters of the incident beam analysed. It is shown from the analysis that the principal curvatures of phase front are not zero at the reference planes where any of the corresponding principal axes of the beam spot obtains its minimum, and the conditions where the principal curvatures are zero is discussed.     

焙烧态镁铝水滑石对I~-的吸附行为研究

采用共沉淀法制备了镁铝水滑石,并利用XRD、FT-IR和SEM对材料进行了表征。在此基础上,系统研究了不同焙烧温度、初始pH值、振荡时间、初始I~-浓度等对焙烧态镁铝水滑石吸附I~-性能的影响。结果表明:500℃焙烧条件下所制备的镁铝水滑石CLDH-500对I~-的吸附性能最优。在初始I~-浓度为500mg/L、初始pH=6.0的条件下,8h达到吸附平衡,最大吸附容量为217.22mg/g。对吸附过程用准一级、准二级动力学模型和粒内扩散模型模拟。结果显示,其吸附过程符合准一级动力学模型和粒内扩散模型(R~20.96);Langmuir模型拟合结果(R~20.99)显示,I~-在CLDH-500上为单分子层吸附。该研究结果可为放射性废液中I~-的去除提供技术和理论支持。     

Conductive nonwetting flexible substrate

In this paper an easy method to prepare flexible conductive substrates has been demonstrated. The substrates are mainly PET (PolyEthyleneTerephthalate), on which AgNW (silver nanowire) were deposited by spin casting method. For adhesion purpose a common cosmetic material has been utilized. The material provides versatile features to these coated substrates, including robustness, hydrophobicity with transparent bracing of nanowires (NW) with the flexible substrate. Four probe conductivity measurement shows the resistivity is 12 Ω/cm and is comparable to that of commercially available indium tin oxide (ITO) coated substrates. This method is cheap, easy and can be used for different objectives like flexible thin film photovoltaic, light emitting diodes, photosensors etc.     

Effects of uncertainty on a tire closed-loop supply chain network

In a closed-loop supply chain (CLSC) network, there are both forward and reverse supply chains. In this research, a tire remanufacturing CLSC network is designed and optimized based on tire recovery options. The objective of the optimization model is to maximize the total profit. The optimization model includes multiple products, suppliers, plants, retailers, demand markets, and drop-off depots. The application of the model is discussed based on a realistic network in Toronto, Canada using map. In addition, a new decision tree-based methodology is provided to calculate the net present value of the problem in multiple periods under different sources of uncertainty such as demand and returns. Furthermore, the discount cash flow is considered in the methodology as a novel innovative approach. This methodology can be applied in comparing the profitability of different design options for CLSCs.     

Electronic structure,carrier mobility and device properties for mixed-edge phagraphene nanoribbon by hetero-atom doping

Phagraphene, a new carbon allotrope, was proposed recently. We here select a mixed-edge phagraphene ribbon to study B-, N-, and BN-doping effects respectively on the geometric stability, electronic structure, carrier mobility, and device property. Calculations show that the energetic and thermal stability for these ribbons are very high. With different doping types and doping sites, the bandgap size of a ribbon may be nearly unchanged, increased, or decreased as compared with the intrinsic ribbon, and even become a metal, thus presenting fully tunable electronic structures. For this, the charge transfer shifting edge bands and the new formed hybridized bands due to doping play a crucial role. More interestingly, doping at different positions can regulate the carrier mobility of ribbon, and the difference of two orders of magnitude for hole mobility can be generated by BN-doping. In addition, the study on device property shows that there is a prominent negative differential resistance characteristics occurring in a BN-doped ribbon device. These findings are meaningful for understanding the doping effects on electronic properties of phagraphene nanoribbons.     

Compatibilization of ethylene/maleic anhydride/glycidyl methacrylate terpolymer for poly(phenylene sulfide)/poly(amide‐66) blends

In this article, a terpolymer of ethylene, maleic anhydride, and glycidyl methacrylate (EMG) was used to enhance the compatibilization between poly(phenylene sulfide) (PPS) and polyamide‐66 (PA66). The mechanical properties, morphology, crystalline and melting behavior, and rheology of blends were discussed. The results showed that EMG was a good compatibilizer for PPS and PA66 through chemical reaction with them. The new generated polymer could prevent the aggregation of dispersed particles and reinforce the interface bonding. In addition, it could not only act as a nucleating agent for PA66 to refine its spherulites and improve its crystallinity but also promote the apparent viscosity of blends and enhance the non‐Newtonian behavior. The results will be useful to make high performance PPS/PA66 alloy with low cost and enlarge the application scope of PPS and PA66 resin. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Highly Regioselective and Active Rhodium/Bisphosphite Catalytic System for Isomerization–Hydroformylation of 2-Butene

Abstract  

The formation of linear aldehyde from isomerization–hydroformylation of 2-butene represents an important subject and current task in industry. Both high activity and excellent regioselectivity were achieved in the rhodium-catalyzed 2-butene isomerization–hydroformylation with 2,2′-bis(dipyrrolylphosphinooxy)-1,1′-(±)-binaphthyl (1) as ligand. Bulky phosphite with electron-withdrawing pyrrol groups dramatically improved the selectivity of linear product, and a good yield of 90.5% aldehydes was obtained with an excellent linear aldehyde regioselectivity of 95.3% under optimized condition.     

Keggin type inorganic–organic hybrid material containing Mn(II) monosubstituted phosphotungstate and S-(+)-sec-butyl amine: Synthesis and characterization

A new inorganic–organic POM-based hybrid material comprising Keggin type mono manganese substituted phosphotungstate and enantiopure S-(+)-sec-butyl amine was synthesized in an aqueous media by simple ligand substitution method. The synthesized hybrid material was systematically characterized in solid as well as solution by various physicochemical techniques such as elemental analysis, TGA, UV–vis, FT-IR, ESR and multinuclear solution NMR (³¹P, ¹H, ¹³C). The presence of chirality in the synthesized material was confirmed by CD spectroscopy and polarimeter. The above study reveals the attachment of S-(+)-sec-butyl amine to Keggin type mono manganese substituted phosphotungstate through N → Mn bond. It also indicates the retainment of Keggin unit and presence of chirality in the synthesized material. An attempt was made to use the synthesized material as a heterogeneous catalyst for carrying out aerobic asymmetric oxidation of styrene using molecular oxygen. The catalyst shows the potential of being used as a stable recyclable catalytic material after simple regeneration without significant loss in conversion.     

A three-dimensional lead borate with a fluorite net constructed from different cluster building units

Presented here is a new three-dimensional lead borate, namely, PbB₂O₄ (denoted as SCU-8). This compound has a fluorite net constructed from two different cyclic building units: 4-connected Pb₃O₆ cluster and 8-connected B₁₂O₂₄ cluster. It is a wide-gap semiconductor with the band gap of 4.0 eV. The band structure and density of states of the compound were also calculated based on density functional theory.