电磁诱导透明和导致极慢光速的机制

根据有关文献 ,描述了电磁诱导透明和导致光速极慢的物理机制 ,并对实验结果也做了介绍     

酸性膦酸酯碱皂微乳体系的红外光谱研究

近年来对溶剂革取过程中有机相形成微乳状液的研究正引起人们的重视同，我们曾用付里叶变换红外光谱法研究过钢皂及钾皂2一乙基已基股酸单·2一乙基已基酯（简写为NaA及KA下同）加水形成微乳状液的过程，观察到P二0，P－0－C，P－0－HH－0－H和0－H等基团吸收谱带频率或强度的变化［‘剑．本文进一步对＃、销和钾三种碱金属皂化2一乙基已基胁酸单一2一乙基已基酯有机相微乳状液的形成及其红外光谱作深入研究．1实验部分五．1样品的制备问将金属捏、销和钾各置于2一乙基巴基磷酸单一2一乙基已基酯（以HA表示，下同）一正庚烷中加热回流…     

The first example of enantioselective isocyanosilylation of meso epoxides with TMSCN catalyzed by novel chiral organogallium and indium complexes

The desymmetrization ring opening of meso epoxides using trimethylsilyl cyanide catalyzed by organogallium and indium complexes with binaphthol monoether derivatives as chiral ligands gave beta-isocyanohydrins with moderate to excellent enantioselectivities of up to 95% ee.     

CRYSTALLIZATION AND MECHANICAL PROPERTIES OF POLYPROPYLENE FILLED WITH SiO2 NANOPARTICLES

Oleic acid （OA）-modified SiO2 （OA-m-SiO2） nanoparticles were prepared using surface modification method. Infrared spectroscopy （IR） was used to investigate the structure of the OA-m-SiO2 nanoparticles, and the result showed that OA attached onto the surface of SiO2 nanoparticles through esterification. Effect of OA concentration on the dispersion stability of OA-m-SiO2 in heptane was also studied, and the result indicated that OA-m-SiO2 nanoparticles were dispersed in heptane more stably than the unmodified ones. OA-m-SiO2 nanoparticles can also be dispersed in polypropylene （PP） matrix in nano-scale. The effect of OA-m-SiO2 on crystallization of PP was studied by means of DSC. It was found that the introduction of OA-m-SiO2 resulted in significant increase in the crystallization temperature, crystallization degree and crystallization rate of PP, and OA-m-SiO2 could effectively induce the formation of β-crystal PP. Effect of OA-m-SiO2 content on mechanical properties of PP/OA-m-SiO2 nanocomposites was also studied. The results show that OA-m-SiO2 can significantly improve the mechanical properties of PP.     

Dual-Function HKUST-1: Templating and Catalyzing Formation of Graphitic Carbon Nitride Quantum Dots Under Mild Conditions

Graphitic carbon nitride quantum dots (g-CNQDs) are highly promising photoresponsive materials. However, synthesis of monodispersed g-CNQDs remains challenging. Here we report the dual function of MOF [Cu₃BTC₂] (HKUST-1) as a catalyst and template simultaneously to prepare g-CNQDs under mild conditions. Cyanamide (CA), a graphitic carbon nitride precursor, catalytically dimerized inside the larger MOF cavities at 90 °C and condensed into g-CNQDs at 120 °C in a controlled fashion. The HKUST-1 template was stable under the reaction conditions, leading to uniform g-CNQDs with a particle size of 2.22±0.68 nm. The as prepared g-CNQDs showed photoluminescence emission with a quantum yield of 3.1 %. This concept (MOF dual functionality) for catalyzing CA polycondensation (open metal sites (OMSs) effect) and controlling the produced particle size (pore-templating effect), together with the tunable MOF porosity, is expected to produce unique g-CNQDs with controllable size, morphology, and surface functionality.     

Advanced Bifunctional Oxygen Reduction and Evolution Electrocatalyst Derived from Surface‐Mounted Metal–Organic Frameworks

Metal–organic frameworks (MOFs) and their derivatives are considered as promising catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), which are important for many energy provision technologies, such as electrolyzers, fuel cells and some types of advanced batteries. In this work, a “strain modulation” approach has been applied through the use of surface‐mounted NiFe‐MOFs in order to design an advanced bifunctional ORR/OER electrocatalyst. The material exhibits an excellent OER activity in alkaline media, reaching an industrially relevant current density of 200 mA cm^?2 at an overpotential of only ≈210 mV. It demonstrates operational long‐term stability even at a high current density of 500 mA cm^?2 and exhibits the so far narrowest “overpotential window” ΔE_ORR‐OER of 0.69 V in 0.1 m KOH with a mass loading being two orders of magnitude lower than that of benchmark electrocatalysts.     

可调光瞳滤波器的轴向焦移及扩展焦深

光学超分辨、焦深扩展及焦移3种效应一直受到研究人员的关注,且在光学显微成像、光学校准、光学相干层析成像及光存储中有着重要的应用.提出一种可调谐光瞳滤波器来实现光学系统的轴向焦移及扩展焦深.该光瞳滤波器由两个完全相同且相互平行的λ/4波片和置于其间的λ/2波片组成,其中λ/2波片分为两个可作相对旋转的区域,并且通过推导得...     

Laser induced damage of multi-layer dielectric used in pulse compressor gratings

Laser induced damage threshold (LIDT) of multi-layer dielectric used in pulse compressor gratings (PCG) was investigated. The sample was prepared by e-beam evaporation (EBE). LIDT was detected following ISO standard 11254-1.2. It was found that LIDTs of normal and 51.2°incidence (transverse electric (TE) mode) were 14.14 and 9.31 J/cm2, respectively. A Nomarski microscope was employed to map the damage morphology, and it was found that the damage behavior was pit-concave-plat structure for normal incidence, while it was pit structure for 51.2°incidence with TE mode. The electric field distribution was calculated to illuminate the difference of LIDT between the two incident cases.     

位相物体的暗场成像

本文介绍一种便于实现的位相物体暗场成像方法，并给出了实验结果．     

Synthesis and Thermal Performance of Polyurea Microcapsulated Phase Change Materials by Interfacial Polymerization

Microencapsulated phase change materials with paraffin as the core material were synthesized by interfacial polymerization of isophorone diisocyanate with diethylene triamine. The particle size and particle size distribution, morphology, thermal performance and the encapsulation efficiency of the prepared materials were investigated. The results of Fourier transform infrared spectrometer and X-ray photoelectron spectroscopy suggested that the paraffin core was well encapsulated by the polyurea resin. The particle size of the prepared materials decreased and its distribution became narrow with the increase of the emulsification time, stirring speed and emulsifier amount. The thermal gravimetric analysis indicated that the prepared materials exhibited good thermal stability, while the differential scanning calorimetry their high encapsulation efficiency.