辛德比斯病毒6K蛋白在宿主细胞内的分布

6k蛋白是Sindbis病毒(SbV)26S基因组编码的一个仅有55个氨基酸的小分子蛋白质,其生物学功能甚至在细胞内的分布至今尚不清楚。最近在M.Schlesinger实验室中用人工合成的6k多肽得到抗6k蛋白的抗体,使我们的上述工作得到进行。本实验用直径20nm的胶体金—proteinA和直径为5nm的胶体金—羊抗兔抗体的复合物,用常规的免疫电镜技术,先后标记了SbV感染的整装细胞及用于冰冻蚀刻的样品,以观察6k蛋白在细胞表面的分布,又标记了Triton×100处理的整装细胞以研究6k蛋白与细胞骨架的关系。同时还标记了低温包埋剂(LK4M)     

家蚕质多角体病毒RDRP的免疫电镜定位研究

以原核表达BmCPV RDRP重组蛋白为抗原制备的兔抗血清为一抗,直径15nm山羊抗兔IgG 胶体金为二抗。应用3%多聚甲醛 0 1%戊二醛混和固定液、K4M低温包埋剂和紫外光聚合制备的样品进行免疫电镜观察,结果感染BmCPV(C)病蚕的中肠柱状细胞中,游离和病毒多角体中BmCPV的病毒粒子均能结合胶体金颗粒,平均标记率为25%左右,认为BmCPV(C) RDRP基因编码的蛋白应为BmCPV病毒的结构蛋白,位于病毒的衣壳上。其中一抗的使用浓度为1∶200,二抗的使用浓度为1∶40,可以获得较好的免疫标记效果和较少的非特异性标记。     

扫描电镜显示细胞表面的分子标记

为了研究细胞表面特异蛋白质的分布,铁蛋白、乳胶颗粒、胶体金甚至病毒颗粒一度都曾作为扫描样品的标记物。但目前最有潜力并表现出巨大优越性的无疑是新近发展起来的胶体金标记技术。我们用直径20nm的蛋白A—胶体金和抗水泡性口炎病毒(vsv)表面膜蛋白(G蛋白)的抗体及抗辛德毕斯病毒(sbv)表面膜蛋白(E_1和E_2蛋白)的抗体,按常规免疫标记并经过我们实验室改进的方法,分别标记了VSV和sbv感染的BHK-21细胞或鸡胚成纤维细胞,经固定和临界点干燥后,镀以厚度约为50A的1金膜,在Hitachi S-570扫描电镜下观察。     

胶体金免疫电镜技术用于植物病毒的检测

胶体金免疫电镜技术具有步骤简便。胶体金探针能精确定位、电镜下分辨率高等优点,给细胞化学标记体系带来了一种改革,近年来越来越多地应用于生物学和医学研究中,如:细胞内某些生物活性物质的定位研究、组织细胞形态发生研究、酶的研究等,但在农业科研中的应用还很少。尤其在病毒检测方面,目前国内只见到以胶体金免疫电镜技术检测动物病毒的报道,而用于植物病毒检测的报道尚无。本文报道了以改良的柠檬酸钠—鞣酸还原法制备大小适于植物病毒标记的胶体金颗粒的方法,制备的胶     

病毒感染单层细胞的免疫标记与断裂技术

用抗Sindbis病毒(SbV)囊膜蛋白E_1和E_2的抗体及抗Vesicular Stomatitis病毒(VSV)囊膜蛋白(G蛋白)的抗体分别对病毒感染的BHK-21细胞进行胶体金免疫标记,然后按冰冻蚀刻的制样程序制备铂-碳复型膜以研究病毒囊膜蛋白在细胞质膜上的定位与分布。本文扼要地介绍了这一技术的操作过程,同时,结合我们自己的工作对该技术的要点及其应用进行了讨论。     

冰冻蚀刻胶体金标记技术

冰冻蚀刻技术主要的优越性之一是可以显示出镶嵌在细胞膜内的蛋白质颗粒,而对这些种类,数量繁多的膜内微粒的定性与定量研究,则是近几年刚刚建立的一个重要的电镜新技术。本实验用直径5nm的胶体金一羊抗兔抗体和直径20nm的胶体金一蛋白A的复合物,以及抗辛德毕斯病毒(sbv)表面糖蛋白E和抗sbv的抗体及抗水泡性口炎病毒(vsv),表面糖蛋白的抗体,分别标记了sbv或vsv感染的BHK—21单层细胞,经固定和甘油处理后,再把长有细胞单层的盖玻片小心裁成大小1～2mm的小块,在Balzars冰冻蚀刻仪中断裂、喷镀复型膜。仅用蒸馏水将复型膜连同细胞碎片漂起,即可捞在400目的载网上。     

采用免疫胶体金标记结合负染色电镜技术对体外组装的中间纤维定性

将免疫胶体金标记与电镜负染色技术相结合，清晰显示体外组装的波形纤维具有１０ｎｍ中间纤维结构特征，抗波形纤维蛋白－金颗粒特异地标记在波形纤维上，用抗波形纤维蛋白－金颗粒对体外组装的微管进行标记则呈阴性反应。实验结果表明将免疫胶体金标记与电镜负染色技术相结合可以同时显示体外组装的细胞骨架纤维的精细结构和蛋白属性。     

低丰度蛋白Mlo的免疫金标记技术研究

小麦Mlo蛋白是一种低丰度蛋白。本文利用Mlo蛋白的2种抗血清对不同标记条件下的免疫胶体金标记情况进行了研究。结果表明，一抗结合时间对标记结果有影响，60min的标记时间对Mlo蛋白定位比较合适；小麦Mlo蛋白11．2抗血清对Mlo蛋白的标记效果要比CT抗血清的标记效果好；IgG胶体金探针要比蛋白A胶体金探针更适合于对低丰度蛋白的检测。     

银增感免疫电镜的效果观察

胶体金免疫民镜技术是利用抗原和抗体特异性结合，在电镜下检测与抗体结合电子密度高的胶体金，确定抗原位置。因此已成为研究细胞化学的重要技术，得到广泛应用。但被检的胶体金粒子直径一般在10nm左右，很难在低倍下、大视野观察不同细胞的标记情况，为此，增大胶体金颗粒十分必要。     

感染番茄斑萎病毒和番茄环纹斑点病毒的植物叶片细胞病理变化观察

应用透射电子显微镜观察比较了番茄斑萎病毒（ TSWV）和番茄环纹斑点病毒（ TZSV）感病植物叶片的细胞超微结构,发现两种病毒在病变细胞内的形态及细胞病理变化特征相似,但病毒含量及细胞受损程度存在明显差异。与TSWV相比,TZSV侵染细胞的病变程度更为严重,叶绿体产生大的囊泡,片层结构被破坏,线粒体也发生囊泡化,而TSWV侵染的细胞内线粒体保存相对完好。高压冷冻－冷冻置换制备的样品细胞病理结构与常规化学固定的相似,但对膜结构的保存更加良好。该结果从细胞病理学上证明了TZSV在田间对农作物造成的危害更加严重。     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.     

High-quality single-crystal CdSe nanoribbons and their optical properties

Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources＇ evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping （266 nm） at power densities of 25-153 kW/cm^2. The full width half maximum （FWHM） of the lasing mode is 0.67 nm     

Propagation of hermite-cosh-gaussian beams passing through ABCD optical system with an annular aperture

By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.     

Influence of polarization extinction ratio on distributed polarization coupling detection

Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.     

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正Communications—VLSI Researches and industries of telecommunications have been growing rapidly in the last 20 years and will keep their high growing pace in the next decade.The involved researches and developments cover mobile communications,highway and last-mile broadband communication,domain specific communications,and emerging D2D M2M communications.Radio communication steps into its