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71.
Sudan black B (SBB) was used to investigate as the nonionic diazo dye-doped in polymer dispersed liquid crystal (PDLC) display, by polymerization-induced phase separation (PIPS) method. The maximum absorbance, contrast ratio, dichroic ratio and the order parameter of nonionic diazo dye in nemetic host (TL203) were investigated using UV?CVis polarized spectroscopy. The orientation of the dye molecules was controlled by electric field, which enabled the contrast ratio of the dye to be obtained by electrically switching. The change occurring on droplet morphologies and electro-optical properties of PDLC film with the change in contents of Sudan black dye and liquid crystals (LC) contents was investigated. We found an increase in LC droplet sizes with the increase of diazo dye and LC contents. Moreover the addition of small amount of nonionic diazo dye reduced the threshold voltage (V $_{\boldsymbol{\rm th}})$ , increased off-state transmittance, enhanced the contrast ratio and decreased the response time of dye-doped PDLC. Additionally the change in transition temperature of LC and changes in LC droplet morphologies with the addition of dye were also observed. Such changes were observed with the images taken by polarized optical microscope (POM). The detail discussions on such behaviours were also made.  相似文献   
72.
Lee SK  Kim GS  Wu Y  Kim DJ  Lu Y  Kwak M  Han L  Hyung JH  Seol JK  Sander C  Gonzalez A  Li J  Fan R 《Nano letters》2012,12(6):2697-2704
We report on the development of a nanowire substrate-enabled laser scanning imaging cytometry for rare cell analysis in order to achieve quantitative, automated, and functional evaluation of circulating tumor cells. Immuno-functionalized nanowire arrays have been demonstrated as a superior material to capture rare cells from heterogeneous cell populations. The laser scanning cytometry method enables large-area, automated quantitation of captured cells and rapid evaluation of functional cellular parameters (e.g., size, shape, and signaling protein) at the single-cell level. This integrated platform was first tested for capture and quantitation of human lung carcinoma cells from a mixture of tumor cells and leukocytes. We further applied it to the analysis of rare tumor cells spiked in fresh human whole blood (several cells per mL) that emulate metastatic cancer patient blood and demonstrated the potential of this technology for analyzing circulating tumor cells in the clinical settings. Using a high-content image analysis algorithm, cellular morphometric parameters and fluorescence intensities can be rapidly quantitated in an automated, unbiased, and standardized manner. Together, this approach enables informative characterization of captured cells in situ and potentially allows for subclassification of circulating tumor cells, a key step toward the identification of true metastasis-initiating cells. Thus, this nanoenabled platform holds great potential for studying the biology of rare tumor cells and for differential diagnosis of cancer progression and metastasis.  相似文献   
73.
A new authentication scheme based on a one-way hash function and Diffie-Hellman key exchange using smart card was proposed by Yoon et al.in 2005.They claimed that the proposed protocol is against password guessing attack.In this paper,the author demonstrate that Yoon's scheme is vulnerable to the off-line password guessing attack by using a stolen smart card and the DoS attack by computational load at the remote system.An improvement of Yoon's scheme to resist the above attacks is also proposed.  相似文献   
74.
Inorganic nanowires are among the most attractive functional materials, which have emerged in the past two decades. They have demonstrated applications in information technology and energy conversion, but their utility in biological or biomedical research remains relatively under‐explored. Although nanowire‐based sensors have been frequently reported for biomolecular detection, interfacing nanowire arrays and living mammalian cells for the direct analysis of cellular functions is a very recent endeavor. Cell‐penetrating nanowires enabled effective delivery of biomolecules, electrical and optical stimulation and recording of intracellular signals over a long period of time. Non‐penetrating, high‐density nanowire arrays display rich interactions between the nanostructured substrate and the micro/nanoscale features of cell surfaces. Such interactions enable efficient capture of rare cells including circulating tumor cells and trafficking leukocytes from complex biospecimens. It also serves as a platform for probing cell traction force and neuronal guidance. The most recent advances in the field that exploits nanowire arrays (both penetrating and non‐penetrating) to perform rapid analysis of cellular functions potentially for disease diagnosis and monitoring are reviewed.  相似文献   
75.
三星美术馆     
正总规划面积27 000m2的三星美术馆项目由OMA于1997年设计完成。综合体坐落于市中心附近的汉南洞住宅区,由OMA、马里奥·博塔和让·努维尔分别设计的三座建筑构成。OMA设计的大楼总面积达13 100m2,包括临时当代展览、媒体和办公空间。三座大楼汇聚于中央多功能室,形成大厅和问询处。经由直通多功能室的坡路穿过OMA  相似文献   
76.
Minsuk Cho , founder of Seoul-based Mass Studies, describes the shifting environment of practice: a world in which curators and clients are already anticipating the way that future architecture will take on a new level of interactivity, responding to personal communication devices. There is a bittersweet flavour to these accounts of projects commissioned by curators that seek to maximise the interactions between the public and the making of pavilions. The irony is sharpened by the urban context of Seoul, a densely populated city in which individuals seek to excise themselves from the relentless interactions of everyday living.  相似文献   
77.
A 51-year-old Korean man with end-stage renal disease and who was on intermittent hemodialysis was admitted with progressive dysarthria, gait disturbance, and myoclonus. The liver function tests and the electrolyte and arterial gas analyses were normal. The Magnetic resonance imaging scan showed a diffuse symmetric high signal intensity in the basal ganglia on the T2-weighted image. After a thorough history taking, we knew that he had been treated with metformin for 3 months at other hospital without our hospitals staff's knowledge. After stopping the metformin, the patient's neurologic signs and symptoms disappeared and the Magnetic resonance imaging findings after 20 days were markedly improved.  相似文献   
78.
The effectts of 0, 100, 250, 500 and 1000 ppm of α-, γ-, or δ-tocopherol on oxidative stability of purified soybean oil in the dark at 55°C were studied. We measured peroxide value and headspace oxygen consumption in the samples. Purified soybean oil was prepared by liquid column chromatography. Tocopherols acted as antioxidants or prooxidants depending on their concentration. Optimum concentrations of α -, γ -, and δ– tocopherols to increase oxidative stability was 100, 250 and 500 ppm, respectively. The tocopherols had significant prooxidant effect (P < 0.05) at higher concentrations above this.  相似文献   
79.
设计类别:博览、展示建设地点:上海浦东高科西路浦明路场地面积:6000 m~2建筑面积:7683.5 m~2建造时间:2010年1欢乐城市韩国馆的设计以"融合"为主题,塑造出"符号"和"空间"的融合体:符号即为空间,空间亦为符号。韩国馆试图成为世博园中充满欢乐的场所,并呈现出强烈的国家色彩,  相似文献   
80.
对机械合金化制备的玻璃工业中用作结构零件的Pt-5%ZrO2(体积分数)的进行表征。通过锆丝电爆炸法制备氧化锆(ZrO2)纳米颗粒(粒径100 nm),并在室温下与铂粉(粒径44?m)球磨2~72 h。普通球磨至48 h时,铂粒径遵循经典的递减趋势,至72 h时观测到颗粒团聚现象。晶粒尺寸演变规律与颗粒尺寸规律相似,48 h后减至50 nm左右。但是,铂晶粒的均方根应变规律相反,一直在增长,直至48 h时得到最大值,然后出现弛豫。粉末球磨48 h后,采用放电等离子体烧结制成块体。根据测量得到烧结体的质量损失表明:合金虽然相对密度较低,但有较好的热稳定性。  相似文献   
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