分析非轴对称腔的复光线数值迭代法

将像散光束的复光线表示法用于分析非轴对称腔，并对有复杂像散的折迭腔作了数值迭代计算以说明方法的应用．

失调复光学系统的矩阵描述与等效变换

基于复光线概念 ,采用矩阵光学方法研究了 3× 3复光线矩阵的分解问题 ,并以失调高斯透镜和失调傅里叶变换系统为例 ,说明失调复光学系统的等效变换。研究表明 ,失调光学系统的增广矩阵可用三个基本矩阵的有序乘积表示。

Visible-Light Activities of Erbium Doped BiVO4 Photocatalysts

Er-doped BiVO4 composite photocatalyst was hydrothermal synthesized and characterized by X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray Spectroscopy, X-ray photoelectron spectroscopy, and UV-Vis diffuse reflectance spectra techniques. The activity of the catalyst was determined by oxidative decomposition of methyl orange in aqueous solution under visible-light irradiation. X-ray photoelectron spectroscopy and energy-dispersive X-ray Spectroscopy analysis revealed that the doped Er existed in the form of Er2O3. It also showed that the Er doping can enhance the visible-light absorption abilities of catalysts and their visible-light-driven photocatalytic activities in comparison with those of pure BiVO4.

Design and fabrication of ultrasmall arrayed waveguide grating multiplexers based on Si nanowire waveguides

The large refractive index difference between Si and SiO2 makes it possible to realize ultrasmall photonic integrated circuits. A 5×5 ultracompact arrayed waveguide grating multiplexer based on 500×250 nm Si nanowire waveguides is designed and fabricated by using the technologies of E-beam writing and amorphous-Si deposition. The mea- sured channel spacing is about 1.5 nm (close to the design value) and the channel crosstalk is about –8 dB.

Enhancing Structural Stability and Pervaporation Performance of Composite Membranes by Coating Gelatin onto Hydrophilically Modified Support Layer

The interfacial compatibility of composite membrane is an important factor to its structural stability, andseparation performance. In this study, poly （ether sulfone） （PES） support layer was first hydrophilically modified with poly（vinyl alcohol） （PVA） via surface segregation during the phase inversion process. Gelatin （GE） was then cast on the PVA-modified PES support layer as the active layer followed by crosslinking to fabricate composite membranes for ethanol dehydration. The enrichment of PVA on the surface of support layer improved interfacial compatibility of the as-prepared GE/PVA-PES composite membrane. The water contact angle measurement and X-ray photoelectron spectroscopy （XPS） data confirmed the surface segregation of PVA with a surface coverage density of -80%. T-peel test showed that the maxima/force to separate the support layer and the active layer was enhanced by 3 times compared with the GE/PES membrane. The effects of PVA content in the support layer, crosslinking of GE active layer and operating parameters on the pervaporative dehydration performance were investigated. The operational stability of the composite membrane was tested by immersing the membrane in ethanol aqueous solution for a period of time. Stable pervaporation performance for dehydration of 90% ethanol solution was obtained for GE/PVA-PES membrane with a separation factor of -60 and a permeation flux of -1910 g.m^-2.h1 without peeling over 28 days immersion.

Overview of Abandoned Mines in the Limpopo Province, South Africa： Rehabilitation Challenges

South Africa is facing enormous financial, environmental and social challenges posed by abandoned mines. This investigation focused on field verification of 850 abandoned mines and associated rehabilitation challenges in the Limpopo Province. The investigations included desktop studies, standardised field-based ranking system and sampling. The waste material samples were analysed using XRF （X-ray fluorescence spectrometry） at the Council for Geoscience Laboratory. Approximately 5% of 850 abandoned mines in the Limpopo Province require urgent rehabilitation either due to high concentrations of metals from mine dumps or presence of open shafts. For example, copper concentrations at Messina and Spoedwel were 9,719 ppm and 56,160 ppm, respectively. Birthday Gold Mine in Giyani area is characterised by un-safe open shafts and un-stable grounds which poses safety problems and limits the future land-use. Although these investigations have been conducted, it is not possible to rehabilitate all abandoned mines mainly due to limited financial resources. The abandoned mines close to human settlement are given priority due to their immediate threat to people. This study recommends that rehabilitation of abandoned mines should take cognisance of the sustainable future land use that will favour the creation of jobs and nature conservation.

Assessment of nanocomposite photonic systems with the X-ray photoelectron spectroscopy

The chemical compositions of Ag-Er co-doped phosphate and silicate glasses were investigated with X-ray photoelectron spectroscopy with the purpose to identify the chemical state of silver. The analysis of the Ag 3d core lines show the presence of nanometer-sized silver particles in each of the annealed samples,even if these Ag 3d lines appear to be very different from each other. We explain these results as a different interaction of silver with the two glasses matrix,which leads to a different nucleation rate of the Ag clusters.

Microstructure and abrasive wear behaviour of anodizing composite films containing Si C nanoparticles on Ti6Al4V alloy

Anodized composite films containing Si C nanoparticles were synthesized on Ti6Al4 V alloy by anodic oxidation procedure in C4O6H4Na2 electrolyte. Scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray photoelectron spectroscopy(XPS) were employed to characterize the morphology and composition of the films fabricated in the electrolytes with and without addition of Si C nanoparticles. Results show that Si C particles can be successfully incorporated into the oxide film during the anodizing process and preferentially concentrate within internal cavities and micro-cracks. The ball-on-disk sliding tests indicate that Si C-containing oxide films register much lower wear rate than the oxide films without Si C under dry sliding condition. Si C particles are likely to melt and then are oxidized by frictional heat during sliding tests. Potentiodynamic polarization behavior reveals that the anodized alloy with Si C nanoparticles results in a reduction in passive current density to about 1.54×10-8 A/cm2, which is more than two times lower than that of the Ti O2 film(3.73×10-8 A/cm2). The synthesized composite film has good anti-wear and anti-corrosion properties and the growth mechanism of nanocomposite film is also discussed.

Preparations of Complex Bimetallic Oxides from Bimetallic Assemblies Containing Different Copper（Ⅱ） Precursors and Comparison of Some Related Systems

This is a mini-review-like article including our recent results and methods for （new） metal oxides and （previously reported） composite materials composed of metal complexes and metal oxides for comparison to enhance anisotropic structural changes intentionally. Some complex inorganic oxides are known that they may be promising color materials （absorbing visible light of certain wavelengths region） having potential application for environmentally benign catalysts, for example, photocatalysts. Chiral copper（Ⅱ） complexes having bidentate amine ligands （[CuL2]2＋） can be acted as cationic building blocks of bimetallic metal complexes. We have prepared some chiral bimetallic complexes with various anionic metal complexes such as [PtCl4]2-, [M02O7]2 and Mn12 clusters （typical single-molecule magnets） which characterized by means of solid-state electronic and CD （circular dichroism） spectra, IR （infrared） spectra, synchrotron XRD （X-ray diffraction） and XAS （soft X-ray absorption spectroscopy）. By sintering these precursor chiral bimetallic complexes, we have prepared complex inorganic oxides from them. The IR spectra indicated substituting metal-ligand bonds and losing organic moieties. The XRD pattern indicated complete changes of crystal structures. The XAS revealed replacing coordination atoms as well as oxidation of valences of metal ions. Furthermore, we will also investigate possibility of patterning by homogeneous precipitation method as bimetallic complexes to prepare desirable complex inorganic oxides.

Research on Preparation of the Composite Materials LiFePO4-Li3V2（PO4）3

The article developed a lithium iron phosphate - composite cathode material of lithium vanadium phosphate. Using X-ray diffraction （XRD）, electronic scanning electron microscopy surface （SEM）, laser particle size analyzer, carbon and sulfur analyzer, and X-ray photoelectron spectroscopy, etc. for the prepared composites were characterized and found the material is mainly crystalline structure of lithium iron phosphate, and lithium vanadium, wherein a small amount of impurities; finer particle size of the material, the particle size distribution is narrow and uniform, smooth particle surface, wrapping in good carbon composite with other materials prepared in comparison the case has a carbon content of about optimum conductivity. To assemble the material into a cell after the 0.1C, IC, 2C when and 5C, the first discharge capacity were 160,145,127 and 109 mA·h·g^-1, after 50 cycles, the discharge capacity of 162, respectively, 144,126 and 106 mA·h·g^-1, which showed good rate characteristics and cycle characteristics.

专利信息

高阻燃涂复光纤色带 本发明提供一种前后线易于识别的涂复光纤色带，具特殊的阻燃性，很薄，适合于布线操作，本发明也提供其制法，本发明涂复光线色带，并行排列的复杂光纤F，上下两侧涂上阻燃树脂，一个表面涂上高阻燃树脂（A）20，而另一面则涂上低阻燃树脂（B）30，涂复的光线色带的特点是高阻燃树脂（A）20和低阻燃树脂（B）30具不同的色彩，

Nitrogen-doped graphene supported Pd@PdO core- shell clusters for C-C coupling reactions

The introduction of nitrogen significantly decreases the metal particle size and improves the performance of metal-based graphene-supported catalysts. In this work, the density functional theory is used to understand the interaction between nitrogen-doped graphene and Pd@PdO clusters. Experiments show that small size Pd@PdO clusters （1-2 nm） can be grown uniformly on nitrogen-doped graphene sheets by a facile oxidation-reduction method. The nanoscale interaction relationship between nitrogen-doped graphene and Pd@PdO clusters is investigated through X-ray photoelectron spectroscopy （XPS） and X-ray absorption spectra （XAS）. The composite catalysts are applied in Suzuki-Miyaura reactions giving high yields and good structural stability. These results have potential impact in design and optimization of future high performance catalyst materials for cross coupling reactions.

Synthesis of Fe304, Fe203, Ag/Fe304 and Ag/Fe203 nanoparticles and their electrocatalytic properties

Two important iron oxides： Fe304 and Fe203, as well as Fe304 and Fe203 nanoparticles mingling with Ag were successfully synthesized via a hydrothermal procedure. The samples were confirmed and characterized by X-ray diffraction （XRD）, and X-ray photoelectron spectroscopy （XPS）. The morphology of the samples was observed by transmission electron microscopy （TEM）. The results indicated Fe304, Fe203, Ag/Fe304 and Ag/Fe203 samples all were nanoparticles with smaller sizes. The samples were modified on a glassy carbon electrode and their elctrocatalytic properties for p-nitropbenol in a basic solution were investigated. The results revealed all the samples showed enhanced catalytic performances by comparison with a bare glassy carbon electrode. Furthermore, p-nitrophenol could be reduced at a lower peak potential or a higher peak current on a glassy carbon electrode modified with Ag/Fe304 or Ag/Fe203 composite nanoparticles.

High-strength composite yarns derived from oxygen plasma modified super-aligned carbon nanotube arrays

Spinning carbon nanotube （CNT） yarns from super-aligned carbon nanotube （SACNT） arrays is a promising approach to fabricate high-strength fibers. However the reported tensile strengths of the as-prepared fibers are far below that of an individual CNT. It is therefore still a challenge to improve their mechanical strengths. Here we report that the tensile strengths and Young＇s moduli can be further improved to 2.2 GPa and 200 GPa respectively, if we first treat the SACNT array with oxygen plasma by using a reactive ion etching （RIE） facility, then dry spin yarns from it and make composite fibers with polyvinyl alcohol. According to the experimental results obtained using scanning electron microscopy （SEM）, Raman spectroscopy and X-ray photoelectron spectroscopy （XPS）, the improvement is attributed to the oxygen RIE process, as it can create functional groups on the outer walls of CNTs and thus improve the interaction between the CNTs and the polymer molecules.

Suppression of Sn^(2+) and Lewis acidity in SnS_(2)/black phosphorus heterostructure for ppb-level room temperature NO_(2) gas sensor

The selective detection of harmful gases is of great significance to human health and air quality,triggering the need for special customizations of sensing material structure.In this study,we prepared a novel Sn S_(2)/black phosphorus(BP)two-dimensional(2D)-2D heterostructure via the in situ hydrothermal growth of Sn S_(2)nanosheets on exfoliated BP lamellae for NO_(2)sensing applications.In the Sn S_(2)/BP composite,the holes with high oxidizability in p-type BP could oxidize Sn^(2+)into Sn^(4+),thus inhibiting the formation of Lewis acidic S vacancies.This Sn^(2+)/Lewis acidity suppression of the composite was further confirmed by X-ray photoelectron spectroscopy and acidic double-layer capacitance analyses,and promoted the adsorption and detection of acidic NO_(2).Owing to its valence and Lewis acidity engineering,the Sn S_(2)/BP heterostructure sensor could detect trace levels of NO_(2)as low as 100 ppb(parts per billion)with high response,fast response/recovery,good stability,and selectivity at room temperature.The high absorption energy of NO_(2)(à0.74 e V),as indicated by the density functional theory calculations,suggests that NO_(2)was chemically adsorbed on the Sn S_(2)/BP surface,which was also evidenced by the in situ Raman spectroscopy results.This work opens up interesting opportunities for the rational design of highly efficient NO_(2)gas sensors through Lewis acidity modification and interface engineering.

Single-/dual-wavelength switchable and tunable compound-cavity erbium-doped fiber laser with super-narrow linewidth

A single-/dual-wavelength switchable and tunable erbium-doped fiber laser(EDFL) with super-narrow linewidth has been proposed and experimentally demonstrated at room temperature. The fiber laser is based on a compound cavity simply composed of a ring main cavity and a two-ring subring cavity(TR-SC). Regardless of single- or dual-wavelength operation, the EDFL could always work well in single-longitudinal-mode(SLM) state at every oscillating wavelength. In dual-wavelength operation, the spacing could be tuned from 0 nm to 4.83 nm. In single-wavelength operation, the EDFL could lase at a fixed wavelength of 1 543.65 nm or another wavelength with a tunable range of 4.83 nm. The super-narrow linewidths of 550 Hz and 600 Hz for two wavelengths are obtained. The proposed EDFL has potential applications in microwave/terahertz-wave generation and high-precision distributed fiber optical sensing.

A novel scheme for synchronous optical sampling based on multicast parametric process

We propose a novel scheme for synchronous optical sampling based on multicast parametric process. The linearly chirped and time-broadened pulses are utilized to replace the traditional mode-locked sampling pulses. An optical sampling rate of 80 Gbit/s is realized by using only one sampling source with repetition rate of 10 GHz.

Self-assemblies of plasmonic gold/layered double hydroxides with highly efficient antiviral effect against the hepatitis B virus

Engineering complex nanocomposites that specifically target the hepatitis B virus （HBV） and overcome the limitations of current therapies such as limited efficacy and serious side effects is very challenging. Here, for the first time, the antiviral effect of engineered plasmonic gold and layered double hydroxide self-assemblies （AuNPs/LDHs） is demonstrated, using HBV as a model virus and hepatoma-derived HepG2.2.215 ceils for viral replication, assembly, and secretion of infectious virions and subviral particles. AuNPs/LDHs were obtained by a simple, cost-effective procedure in which small AuNPs （-3.5 nm） were directly obtained and organized on the surface of larger LDH nanoparticles （-150 nm） by exploiting the capability of MgLDH, ZnLDH, and MgFeLDH to manifest their ＂structural memory＂ in the aqueous solution of Au（O2CCH3）3. The self-assembly approach of AuNPs and LDHs was assessed by transmission electron microscopy （TEM）, X-ray photoelectron spectroscopy （XPS）, powder X-ray diffraction （PXRD）, and UV-Vis analysis （UV-Vis）. All AuNPs/LDHs tested reduced the amount of viral and subviral particles released from treated cells by up to 80% and exhibited good cytocompatibility. AuNPs/MgFeLDH showed the highest antiviral HBV response with more than 90% inhibition of HBV secretion for the whole concentration range. Preliminary studies on the mechanism of HBV inhibition reveals that in the presence of AuNPs/LDHs, HBV particles are sequestered within the treated cells. The antiviral and low cytotoxic plasmonic properties of these Au/LDH nanocomposites indicate that they hold significant potential to be tailored as novel efficient therapeutics for the treatment of hepatitis B.