Accurate Gain Flattening Filters Manufactured by Optical Compensation Monitoring Method

GFFs with less than 0.4 dB peak-to-peak error functions are routinely fabricated using commercially available coating machines by utilizing the natural error compensation mechanism of wavelength variable turning point optical monitoring method.     

III-Nitride Quantum Devices—Microphotonics

Photonic devices based on III-nitrides offer benefits such as UV/blue emission, large band offsets of InN/GaN/AlN heterostructures allowing novel quantum well (QW) device design, and inherently high-emission efficiencies. Furthermore, due to their mechanical hardness and larger band gaps (when compared with conventional semiconductor devices), III-nitride-based devices may operate at much higher temperatures and voltages/power levels for any dimensional configuration and in harsher environments than other semiconductor devices and are expected to provide much lower temperature sensitivities. These are crucial advantages for many applications. Over the last decade, the physics of microsize photonic devices has been investigated. New physical phenomena and properties are expected to dominate as the device size scales down. The microsize light emitters offer benefits over edge emitters such as the ability to create arrays of individually controllable pixels on a single chip, enhanced quantum efficiency, and greatly reduced lasing threshold. Rapid progress in the area of III-nitride microphotonics has been made. The growth and fabrication of micron and submicron size photonic structures based on III-nitride wide bandgap semiconductors has been achieved, and the technology has made it possible to integrate arrays of optical elements to form active photonic-integrated devices. One example is an interconnected µ-LED with enhanced emission efficiency over the conventional LEDs for the same device area. Another example is a µ-LED array with independently addressed pixels or III-nitride microdisplay. III-nitride microdisplay may offer performance that is superior to microdisplays fabricated from liquid crystals and organic LEDs. The third example presented is III-nitride UV Focal Plane Arrays (UV-FPA) of detectors. So far, the operation of AlGaN UV-FPA with size up to 256×256 pixels with 30×30?μm² unit cells has been demonstrated. Together with the nature of their two-dimensional array, these active micro-photonic devices show promise in many important applications, such as optical communications, signal and image processing, optical interconnects, computing, enhanced energy conversion and storage, chemical, biohazard substances, and disease detection, missile and shellfire, atmospheric ozone-level, and flame sensing. III-nitride microlens arrays have been fabricated successfully for blue and UV wavelength applications on GaN and AlN. The successful fabrication of microlens arrays based on III-nitride materials opens the possibility for monolithically integrating nitride-based micro-size photonic devices, as well as coupling light into, out of, and between arrays of III-nitride emitters and detectors, especially for short wavelengths covering the green-blue to deep UV (200?nm) region. Nanofabrication and characterization of photonic crystals with diameter/periodicity as small as 100/180?nm on InGaN/GaN MQW has been achieved. An unprecedented maximum enhancement factor of 20 was obtained under optical pumping. Single-mode ridged optical waveguide devices using GaN/AlGaN heterostructures have been designed, fabricated, and characterized for operation in 1550?nm wavelength window. The feasibility of developing novel photonic integrated circuits based on III-nitride wide bandgap semiconductors for fiber-optical communications has been investigated.     

Vanishing Shear Viscosity Limit in the Magnetohydrodynamic Equations

We study an initial boundary value problem for the equations of plane magnetohydrodynamic compressible flows, and prove that as the shear viscosity goes to zero, global weak solutions converge to a solution of the original equations with zero shear viscosity. As a by-product, this paper improves the related results obtained by Frid and Shelukhin for the case when the magnetic effect is neglected. Supported by NSFC (Grant No. 10301014, 10225105) and the National Basic Research Program (Grant No. 2005CB321700) of China.     

原始地应力及力学参数的测定

本文根据孔壁应力解除法获得的量测应变,提出了采用最优化方法直接确定岩体的泊松比和原始地应力。实例表明,这样获得的原始地应力更符合实际——对应最小的量测残差。     

CRYSTAL AND MOLECULAR STRUCTURE OF A NOVEL Au Ag SUPRACLUSTER COMPOUND [Au_13Ag_12(μ-Br)_4(μ_3-Br)_2(Ph_3P)_10-

<正> [Au13Ag12(μ-Br)1(μ3-Br)2 (Ph3P)10Br2] Br, monoclinic. space group C2/m, a = 36. 496(17). b=16. 878(7), c-=19. 772(9) A , β=99. 87(5)°, V=11998. 9 A3.Z=2. The final R(Rw) is 0. 097(0. 109) for 3779 reflections with I>3σ(I). The structure can he considered as two icosahedral cluster units (AurAg6) sharing one vertex and linked hy six bromine atoms. The Au - Au, Au - Ag. and Ag-Ag distances fall in the ranges of 2. 69-2. 96. 2. 84-3. 02. and 2. 92-3. 26 A, respectively.     

饲育条件下Semisulcospiens decipiens的生长

在饲育温度条件下研究了Ｓ．ｄｅｃｉｐｉｅｎｓ的生长和产仔数及与饲育水温的关系。结果表明水温在上升期和下降期，新生贝和稚贝的生长速度较快，产仔数也较多．成体贝在水温１１℃～２９℃时，都可产出新生贝，以１８℃～２４℃时产出较多．在高温饲育条件下，成体贝的生长速度缓慢。     

链式输送竹片软化机研究

简述了链式输送竹片软化机的设计指导思想和设计方案，重点介绍软化机的构成，参数的确定以及它的优点。     

A FOUR-POINT BOUNDARY VALUE PROBLEM FOR NONLINEAR EQUATION

1IntroductionThemethodofupperandlowersolutionshasbecomeastandardtoolforstudyingthesolvabilityoftwo-pointboundaryvalllcproblemsassociatedwitllsecond-ordernonlineardifferentialequations.Inrecent,years,Rachunkovd[1,2,3]studiedthefour--pointboundaryvalueprobl…     

带有硬相互作用的相对论Boltzmann方程整体解存在性的证明

给出了带有硬相互作用的相对论Ｂｏｌｔｚｍａｎｎ方程初值问题整体解存在性的证明     

闪光Ⅰ号应用于X射线爆轰照相——研究金属射流的穿甲效应

闪光X射线照相技术是研究动载荷及其效应的重要测试手段,特别适用于研究物质在爆炸作用下的瞬变过程,本文介绍了闪光Ⅰ号加速器应用于X射线爆轰照相的基本状况,以及用于观察金属射流穿过高密度物质钨靶的实验技术。