MMW Source CAD in Quasi-Optical Resonator

This paper presents a quasi-optical resonator that design methode basic on IBM PC computer (CAD). There is an exellent method to calculate global optima of the fundamental mode power, fractional power of the fundamental mode and combining efficiency etc. It also presents a process of CAD of microcomputer.     

Efficient Degradation of Iopromide by Using Sulfite Activated with Mackinawite

Iopromide (IOP), an iodinated X-ray contrast medium (ICM), is identified as a precursor to iodide disinfection byproducts that have high genotoxicity and cytotoxicity to mammals. ICM remains persistent through typical wastewater treatment processes and even through some hydroxyl radical-based advanced oxidation processes. The development of new technologies to remove ICMs is needed. In this work, mackinawite (FeS)-activated sulfite autoxidation was employed for the degradation of IOP-containing water. The experiment was performed in a 500 mL self-made temperature-controlled reactor with online monitoring pH and dissolved oxygen in the laboratory. The effects of various parameters, such as initial pH values, sulfite dosages, FeS dosages, dissolved oxygen, and inorganic anions on the performance of the treatment process have been investigated. Eighty percent of IOP could be degraded in 15 min with 1 g L⁻¹ FeS, 400 μmol L⁻¹ sulfite at pH 8, and high efficiency on the removal of total organic carbon (TOC) was achieved, which is 71.8% via a reaction for 1 h. The generated hydroxyl and oxysulfur radicals, which contributed to the oxidation process, were identified through radical quenching experiments. The dissolved oxygen was essential for the degradation of IOP. The presence of Cl⁻ could facilitate IOP degradation, while NO₃⁻ and CO₃²⁻ could inhibit the degradation process. The reaction pathway involving H-abstraction and oxidative decarboxylation was proposed, based on product identification. The current system shows good applicability for the degradation of IOP and may help in developing a new approach for the treatment of ICM-containing water.     

Molten-Salt-Mediated Synthesis of an Atomic Nickel Co-catalyst on TiO2 for Improved Photocatalytic H2 Evolution

Atomic co-catalysts offer high potential to improve the photocatalytic performance, of which the preparation with earth-abundant elements is challenging. Here, a new molten salt method (MSM) is designed to prepare atomic Ni co-catalyst on widely studied TiO₂ nanoparticles. The liquid environment and space confinement effect of the molten salt leads to atomic dispersion of Ni ions on TiO₂, while the strong polarizing force provided by the molten salt promotes formation of strong Ni−O bonds. Interestingly, Ni atoms are found to facilitate the formation of oxygen vacancies (OV) on TiO₂ during the MSM process, which benefits the charge transfer and hydrogen evolution reaction. The synergy of atomic Ni co-catalyst and OV results in 4-time increase in H₂ evolution rate compared to that of the Ni co-catalyst on TiO₂ prepared by an impregnation method. This work provides a new strategy of controlling atomic co-catalyst together with defects for efficient photocatalytic water splitting.     

Grain size engineering and growth mechanism in hydrothermal synthesis of Bi0.5Na0.5TiO3 thin films on Nb-doped SrTiO3 substrates

Journal of Sol-Gel Science and Technology - Considering the full utilization of energy and pursuing thin-film capacitors with high energy-storage density, the grain size engineering is used to...     

Finite particle number description of neutron matter using the unitary correlation operator and high-momentum pair methods

Using bare Argonne V4' (AV4'), V6' (AV6'), and V8' (AV8') nucleon–nucleon (\begin{document}$NN$\end{document}) interactions, the nuclear equations of state (EOSs) for neutron matter are calculated with the unitary correlation operator and high-momentum pair methods. Neutron matter is described using a finite particle number approach with magic number \begin{document}$N=66$\end{document} under a periodic boundary condition. The central short-range correlation originating from the short-range repulsion in the \begin{document}$NN$\end{document} interaction is treated by the unitary correlation operator method (UCOM), and the tensor correlation and spin-orbit effects are described by the two-particle two-hole (2p2h) excitations of nucleon pairs, where the two nucleons with a large relative momentum are regarded as a high-momentum (HM) pair. With increasing 2p2h configurations, the total energy per particle of the neutron matter is well-converged under this UCOM+HM framework. Comparing the results calculated with AV4', AV6', and AV8' \begin{document}$NN$\end{document} interactions, we demonstrate the effects of the short-range correlation, tensor correlation, and spin-orbit coupling on the density dependence of the total energy per particle of neutron matter. Moreover, the contribution of each Hamiltonian component to the total energy per particle is discussed. The EOSs of neutron matter calculated within the present UCOM+HM framework agree with the calculations of six microscopic many-body theories, especially the auxiliary field-diffusion Monte Carlo calculations.     

Strain-Enhanced Metallic Intermixing in Shape-Controlled Multilayered Core–Shell Nanostructures: Toward Shaped Intermetallics

Controlling the surface composition of shaped bimetallic nanoparticles could offer precise tunability of geometric and electronic surface structure for new nanocatalysts. To achieve this goal, a platform for studying the intermixing process in a shaped nanoparticle was designed, using multilayered Pd-Ni-Pt core–shell nanocubes as precursors. Under mild conditions, the intermixing between Ni and Pt could be tuned by changing layer thickness and number, triggering intermixing while preserving nanoparticle shape. Intermixing of the two metals is monitored using transmission electron microscopy. The surface structure evolution is characterized using electrochemical methanol oxidation. DFT calculations suggest that the low-temperature mixing is enhanced by shorter diffusion lengths and strain introduced by the layered structure. The platform and insights presented are an advance toward the realization of shape-controlled multimetallic nanoparticles tailored to each potential application.     

15GHz马赫－陈德尔型Ti：LiNbO_3行波幅度电光调制器

比较了四种马赫－陈德尔调制器的结构特性，表明Ｚ切共面波导（ＣＰＷ）是最好的一种结构。用阶跃倒相电极设计了新型电光光波导幅度调制器，研制了包装式带尾光纤的有５段例相电极的马赫－陈德尔调制器。在１．５３２μｍ波长上，该器件调制带宽为１４．８ＧＨｚ，半波电压为１４Ｖ，消光比为２１．３ｄＢ，光纤－器件－光纤插入损耗７．６ｄＢ。     

Head–Tail Asymmetry as the Determining Factor in the Formation of Polymer Cubosomes or Hexasomes in a Rod–Coil Amphiphilic Block Copolymer

The self‐assembly of a rod–coil amphiphilic block copolymer (ABCP) led to Im m and Pn m polymer cubosomes and p6mm polymer hexasomes. This is the first time that these structures are observed in a rod–coil system. By varying the hydrophobic chain length, the initial concentration of the polymer solution, or the solubility parameter of the mixed solvent, head–tail asymmetry is adjusted to control the formation of polymer cubosomes or hexasomes. The formation mechanism of the polymer cubosomes was also studied. This research opens up a new way for further study of the bicontinuous and inverse phases in different ABCP systems.     

Coupling molecular rigidity and flexibility on fused backbones for NIR-II photothermal conversion

Great attention is being increasingly paid to photothermal conversion in the near-infrared (NIR)-II window (1000–1350 nm), where deeper tissue penetration is favored. To date, only a limited number of organic photothermal polymers and relevant theory have been exploited to direct the molecular design of polymers with highly efficient photothermal conversion, specifically in the NIR-II window. This work proposes a fused backbone structure locked via an intramolecular hydrogen bonding interaction and double bond, which favors molecular planarity and rigidity in the ground state and molecular flexibility in the excited state. Following this proposal, a particular class of NIR-II photothermal polymers are prepared. Their remarkable photothermal conversion efficiency is in good agreement with our strategy of coupling polymeric rigidity and flexibility, which accounts for the improved light absorption on going from the ground state to the excited state and nonradiative emission on going from the excited state to the ground state. It is envisioned that such a concept of coupling polymeric rigidity and flexibility will offer great inspiration for developing NIR-II photothermal polymers with the use of other chromophores.

Low bandgap and large deformation generally conflict each other. This work couples molecular rigidity and flexibility by intramolecular hydrogen bonds and double bonds to achieve NIR-II light absorption and reinforced internal conversion at the same time.     

荧光分光光度法测定矿物油的标准油选择研究

本文研究了我国37种原油、机油和柴油的荧光激发光谱和发射光谱特征。提出用比值法或发射波长法将矿物油分组,尔后选择相应的标准油。该法克服了统一方法制取标准油烦琐、费时的缺点。