YCa_2Cu_3O_(ya)的合成、结构和半导电性

合成了化合物YCa_2Cu_3Oy,这个化合物结构属正交晶系a=6.528A, b=5.421(?),c=10.404(?)。氧含量y=6.55。Yca_2Cu_3Oy是黑色n型半导体材料,室温电阻率1.2×10~5Ω·cm。测量了该化合物的R—T关系,并把它的组成、结构和性质与超导化合物YBa_2Cu_3Oy进行了对比和分析。

PVC膜氯离子选择电极的临床应用研究

本文介绍利用功能高分子活性材料,采用熔融压片成膜的方法研制了PVC膜氯离子选择电极,并对电极性能进行测试并做了临床应用试验,结果表明:电极在10~(-1)M Cl~-中稳定性好,响应时间快,在10~(-1)～10~(-4)M Cl~-中电极呈能斯特响应,其斜率为56～57mV/pCl~-。经临床检测血液标本,该电极抗蛋白、脂类、血球能力强,可以满足临床检测的要求。

东海颗粒有机碳通量的模式计算

本研究论文属于国家科学基金重点研究项目“东海关键海洋通量过程的研究”计划的一个组成部分，通过1998年夏季东海航次，测定了颗粒有机碳的(Particulate Organic Carbon)含量，并研究了东海夏季POC含量的分布特点以及影响因素。同时，通过模式计算了部分站位的POC的垂直表观通量。然后，根据海水悬浮物质、底质物和浮游生物中的DOC的含量，定量的研究了东海的再悬浮现象，计算得到32°N断面和PN断面部分站位的再悬浮比，并计算得到了这些站位的POC净垂直通量，使我们对东海的POC净沉积通量有了一个定量的认识和把握。通过研究，我们发现东海夏季的POC的分布特点是：（1）近岸区域有明显的高值区的存在，并随离岸距离的增加而降低，这主要是受长江径流的影响；（2）在以(32°N, 125°E-125.5°E)为中心的冷涡表层海域存在着另一个POC含量的高值区，随深度增加而降低，在25米层以下随深度的增加而增加，在近底层形成一个新的高值区，研究表明表层高值区主要受生物生长的控制，而底层的高值区的存在与该区域的涡动层或上升流的存在有一定的关系；（3）同时，在东海所研究的两个断面，TSM（Total Suspended Materials）和POC的含量之间表现出了较好的相关性。通过模式研究，计算了六个站位八个层次的POC的垂直通量，其垂直通量为12.43 mg·m~(-2)·d~(-1)-148.23 mg·m~(-2)·d~(-1)，最大值为148.23 mg·m~(-2)·d~(-1)，出现在107站(32°N, 125°E)10米层，最小值为12.43 mg·m~(-2)·d~(-1)，出现在111站(32°0.08N, 125°59.57'E)的底层。通过对东海再悬浮比率的定量研究，计算了五个站和个层次的再悬浮比率。结果表明：（1）表层海水中悬浮物质的再悬浮比率在47.4%-79.18%之间；底层的再悬浮比率在72.75%-96.96%之间；（2）再悬浮比率的最大值出现在106站(32°N, 124°30'E)的底层，而再悬浮比率的最小值出现在102站(32°N, 122°30'E)的表层。在POC重直通量和再悬浮模式计算的基础上，我们计算得到了六个站位八个层次的POC净垂直通量，颗粒有机碳的净垂直通量最大值出现在107站(32°N, 125°E)的10米层，为117.4 mg·m~(-2)·day~(-1)；最小值出现在111站(32°0.08'N, 125°59.57'E)的底层为0.79 mg·m~(-2)·day~(-1)。通过几个站位的模式计算估算了东海颗粒有机碳平均的净沉积通量，其大约为6.55 mgC·m~(-2)·day~(-1)，即2.39gC·m~(-2)·y~(-1)。从而使我们对东海的颗粒有机碳的净垂直通量有了一个定量的认识。

一种高智能化的通用自动胶片判读仪

自动通用胶片判读仪是一种高智能化的精密光学测试设备,采用了计算机控制飞点扫描技术、精密光学测量技术、图象跟踪测量与信息处理技术。飞点管分辨率达4096×4096象元,通过光学系统胶片上获得6.55μm高分辨率,飞点扫描方式灵活多样且可随意控制,通用于目前我国靶场所有的电影经纬仪和高速摄影机35mm胶片的数据判读。具有自动判读和半自动判读两种工作模式,自动判读的速度为5帧/秒,自动判读的精度为σ=±0.011mm,半自动判读的精度为σ=±0.009mm,测量数据可以记录、打印和显示。

Effect of 80.55 MeV/u(12)C(6+) ions on radiosensitivity and cell cycle of human hepatoma cell lines

In this paper, the relationship between radiosensitivity, cell cycle alteration and the change of apoptosis in different human hepatoma cell lines irradiated by heavy ions were studied with the aim of building up the base data for clinical therapy. Exponentially growing hepatoma cell lines were irradiated by 80.55 MeV/u(12)C(6+) ions at a dose of 0 Gy, 0.5 Gy, 1 Gy, 2 Gy, 4 Gy and 8 Gy. The radiosensitivity was assessed by means of the colony-forming assay. The DNA content, the percentage of each cell-cycle phase and the apoptosis rate were obtained with flow cytometry methods. After the irradiation, the SF2 (survival fraction at 2 gray) of SMMC-7721 cells were evidently lower than that of HepG2 cells. The S phase arrest, G2/M phase arrest delay and the apoptosis in the two hepatoma cell lines varied with the increase of the dose and repair time. The heavy ions could obviously kill the human hepatoma cell lines. Compared to HepG2 cells, SMMC-7721 cells were more radiosensitive to C-12(6+) ions.

Effect of La3+ on microwave dielectric properties of (Pb0.45Ca0.55) (Fe0.5Nb0.5)O-3 ceramics

In this work, microwave dielectric properties of A-site substitution by La3+ in (Pb0.45Ca0.55) (Fe0.5Nb0.5) 03 system were investigated. Microwave dielectric properties of A-site charge unbalance substitution of [(Pb0.45Ca0.55)(1-x) La-x] (Fe0.5Nb0.5)O-3(+) (P45CLFN) were improved because the solid solution of small amount of surplus La3+ with (Pb, Ca)(2+) could eliminate oxygen vacancies, and the formation of secondary phase (pyrochlore) was also caused by surplus La3+. The decreasing of dielectric constant with the increase of La3+ content is due to the formation of pyrochlore. The grain size is changed slightly and Q(f) values (7000 similar to 7300 GHz) are almost unchanged at x = 0.02 similar to 0.10, but the temperature coefficient of resonant frequency (TCF) are increased and changed from negative to positive. TCF is zero at x 0.075 with Q(f) = 7267 GHz and K = 89. TCF of all specimens are within +/- 5 x 10(-6)degrees C-1.

6种常用渔药对厚颌鲂鱼苗的急性毒性试验

在水温29~30℃条件下,用硫酸铜与硫酸亚铁合剂(比例5:2)、高锰酸钾、晶体敌百虫、强氯精、溴氯菊脂、甲醛共6种药物对厚颌鲂(Megalobrama pellegrini)鱼苗进行急性毒性试验。试验结果显示,6种药物48h的半致死浓度分别为5.78、6.50、4.90、2.55、0.042、120mg/L,安全浓度分别为0.445、0.528、0.268、0.190、0.003、7.500mg/L,厚颌鲂鱼苗对药物敏感性比一般鱼类高,实际用药时应根据具体情况确定用药时间和用药量,溴氯菊脂不宜作为治疗药物

Narrow line-width resonant cavity enhanced photodetectors operating at 1.55 mu m

A method for fabrication of long-wavelength narrow line-width InGaAs resonant cavity enhanced (RCE) photodetectors in a silicon substrate operating at the wavelength range of 1.3-1.6 mu m has been developed. A full width at half maximum (FWHM) of 0.7 nm and a peak responsivity of 0. 16 A/W at the resonance wavelength of 1.55 mu m have been accomplished by using a thick InP layer as part of the resonant cavity. The effects of roughness and tilt of the InP layer surface, and its free carrier absorption, as well as the thickness deviation of the mirror pair on the resonance wavelength shift and the peak quantum efficiency of the RCE photodetectors are analyzed in detail, and approaches for minimizing them toward superior performance are suggested. (C) 2007 Elsevier B.V. All rights reserved.

1.55-mu m ridge DFB laser integrated with a buried-ridge-stripe dual-core spot-size converter by quantum-well intermixing

A ridge distributed feedback laser monolithically integrated with a buried-ridge-stripe spot-size converter operating at 1.55 mu m was successfully fabricated by means of low-energy ion implantation quantum-well intermixing and dual-core technologies. The passive waveguide was optically combined with a laterally exponentially tapered active core to control the mode size. The devices emit in a single transverse and single longitudinal mode with a sidemode suppression ratio of 38.0 dB. The threshold current was 25 mA. The beam divergence angles in the horizontal and vertical directions were as small as 8.0 degrees x 12.6 degrees, respectively, resulting in 3.0-dB coupling loss with a cleaved single-mode optical fiber.

1.55-mu m Ridge DFB laser and electroabsorption modulator integrated with buried-ridge-stripe dual-waveguide spot-size converter output

A 1.55-mu m ridge distributed feedback laser and electroabsorption modulator monolithically integrated with a buried-ridge-stripe dual-waveguide spot-size converter (SSC) at the output port for low-loss coupling to a cleaved single-mode optical fiber was fabricated by means of selective area growth, quantum-well intermixing, and dual-core technologies. These devices exhibit threshold current of 28 mA, 3-dB modulation bandwidth of 12.0 GHz, modulator extinction ratios of 25.0-dB dc. The output beam divergence angles of the SSC in the horizontal and vertical directions are as small as 8.0 degrees x 12.6 degrees, respectively, resulting in 3.2-dB coupling loss with a cleaved single-mode optical fiber.

High performance of 1.55 mu m DFB integrated with vertically tapered self-aligned spot-size converter

A new type of self-aligned spotsize converter (SSC) integrated 1.55 mum DFB lasers had been proposed in this article. The upper optical confinement layer and the butt-coupled tapered thickness waveguide were regrown simultaneously, which not only offered the separate optimization of the active region and the integrated SSC, but also reduced the difficulty of the butt-joint selective regrowth. The vertical and horizontal far field angles were 9degrees and 12degrees respectively, the 1- dB misalignment tolerance were both 3.6 and 3.4 mum. The directed coupling efficiency to tapered single mode fiber was 48%.

键合法制备硅基1.55μm InP-InGaAsP量子阱激光器

在硅基上成功地制备出了1．55μm InP-InGaAsP量子阱激光器．设计并生长了适合于键合的量子阱激光器结构材料，通过直接键合技术，将Si衬底与InP-InGaAsP外延片键合到一起．剥离去掉InP衬底后，在5～6μm的薄膜上制备出20μm条形边发射激光器．室温下，阈值电流160mA（电流密度为2．7kA／cm^2），功率可达10mW以上（在约350mA电流下），实现了1．55μm长波长边发射激光器与Si的集成．目前，该结果国际上还未见报道．

Fabrication of 1.55μm Si-Based Resonant Cavity Enhanced Photodetectors

A novel bonding method using silicate gel as bonding medium is developed.High reflective SiO2/Si mirrors deposited on silicon substrates by e-beam deposition are bonded to the active layers at a low temperature of 350℃ without any special treatment on bonding surfaces.The reflectivities of the mirrors can be as high as 99.9%.A Si-based narrow band response InGaAs photodetector is successfully fabricated,with a quantum efficiency of 22.6% at the peak wavelength of 1.54μm,and a full width at half maximum of about 27nm.This method has a great potential for industry processes.

Narrow-beam divergence 1.55μm laser diodes with integrated self-aligned spotsize conVerter

This paper describes the high performance of narrow-beam divergence spot size converter (SSC) integrated separately confined heterostructure (SCH) LD. The upper optical confinement layer (OCL) and the butt-coupled tapered thickness waveguide were regrown simultaneously, which not only offered the separated optimization of the active region and the integrated spotsize converter, but also reduced the difficulty of the butt-joint selective regrowth. The threshold current was as low as 5.4 mA, the output power at 55 mA was 10.1 mW, the vertical and horizontal far field divergence angles were as low as 9°and 15°, and the 1-dB misalignment tolerances were 3.6 and 3.4μm, respectively.

镜面起伏对1.55 μm Si基MEMS光滤波器的影响

用传输矩阵方法，在简化的光学模型基础上，分别讨论了分布式Bragg反射镜DBR（Distributed Bragg Reflector）的生长精度及镜面起伏对1.55 μm Si基MEMS（Micro-Electro-Mechanical-System）可调谐光滤波器透射谱的影响。计算表明