Laser-Induced Fluorescence Bronchoscopy for Detection and Localization of Early Lung Cancer

Experimenatal results on the development of a Laser-Induced Fluorescence Bronchoscopy(LIFB) for the detection and localization of early lung cancer are reported in this paper. The system utilizes fluorescence of photosensitizer drug to provide real time video imaging for the examined lung tissue. Color filters are used to differentiate signal from background and a computer image processing technique is also applied to subtract the background. Moreover, a pseudocolor contrast enhancement method was developed to enhance the fluorescence image displayed on the vidio monitor. Suspicious areas are identified by pseudocolor image to guide biopsy, and several clinical trials show that sensitivity and contrast capability of the system should permit the detection and localization of early lung cancer.     

正交各向异性材料热弹性问题的三维无网格法计算模型及应用

建立了正交各向异性材料热弹性问题的三维无网格伽辽金(Element Free Galerkin, EFG)法计算模型。利用该计算模型对三维复合材料汽轮机叶轮和轴承座进行了热弹性分析,对比了材料方向角及热导率因子、热膨胀系数因子和拉压弹性模量因子不同组合情况下轴承座的最大热变形总位移和当量应力值,讨论了材料方向角及上述正交各向异性因子对热变形和当量应力的影响规律,并与各向同性材料进行了对比。结果表明:三维EFG模型的热变形总位移和当量应力相对误差范数分别比有限元法小0.1215%和0.1359%;材料方向角同时影响热变形的大小和方向,但对当量应力方向影响不大;正交各向异性材料因子主要影响热变形和当量应力的大小。在考虑热-机械载荷作用下的三维复合材料零件结构设计中,当以刚度或强度为主要需求时,材料方向角、热导率因子、热膨胀系数因子、拉压弹性模量因子分别在(45°~60°,8:1:4~10:1:5,(1/6):(1/5):1~(1/5):(1/4):1,(7/5):1:(9/5)~(3/2):1:2)或(0°~10°,(1/10):1:(1/5)~(1/8):1:(1/4),(1/5):1:(1/6)~(1/4):1:(1/5),1:(1/5):(1/10)~1:(1/4):(1/8))范围内取值能有效降低轴承座等结构的热变形和当量应力。     

Steady state and time-resolved autofluorescence studies of human colonic tissues

Steady state and time-resolved autofluorescence spectroscopies are employed to study the autofluorescence characteristics of human colonic tissues in vitro. The excitation wavelength varies from 260 to 540 nm, and the corresponding fluorescence emission spectra are acquired from 280 to 800 nm. Significant difference in fluorescence intensity of excitation-emission matrices (EEMs) is observed between normal and tumor colonic tissues. Compared with normal colonic tissue, low nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavin adenine dinucleotide (FAD), and high amino acids and protoporphyrin Ⅸ (PpⅨ) fluorescences characterize high-grade malignant tissue. Moreover, the autofluorescence lifetimes of normal and carcinomatous colonic tissues at 635 nm under 397-nm excitation are about 4.32±0.12 and 18.45±0.05 ns, respectively. The high accumulation of endogenous PpⅨ in colonic cancers is demonstrated in both steady state and time-resolved autofluorescence spectroscopies.     

运载火箭结构动特性分析工具的设计与实现

运载火箭的结构模型复杂,只有通过开发专用的仿真分析软件,才能高效、便捷的对其开展动力学特性分析。为保证工具建设的实用性,该软件基于航天领域应用广泛的Patran/Nastran软件进行二次开发。针对仿真分析流程,设计实现了运载火箭结构动特性分析工具,涵盖了建模与计算模块、结果后处理模块、模态筛选模块与模型修正模块,并提炼了其中的关键技术。经工程实践表明,工具可提升设计效率,且计算结果准确、通用性与扩展性强,在工程中具备良好的应用价值。     

聚(辛二酸-四甘醇酯)的合成及其微相分离结构的研究

通过熔融缩聚合成了一种新型的两亲性聚酯——聚(辛二酸-四甘醇酯)(PTEGSub),利用GPC,NMR,FTIR,TG,DSC等手段对聚合物的结构进行了表征.研究发现,在25℃时,PTEGSub在水中可以形成胶束,粒径主要集中在20～120nm之间,其临界胶束浓度(CMC)随分子量的升高而降低.通过TEM观察了在选择性溶剂中的胶束形态.利用AFM研究了PTEGSub的微相分离,发现聚合物膜中存在有球状的相分离结构.     

The crystal structure and thermal analysis of ZTO and its solvent adducts

Research on Chemical Intermediates - 4,4-azo-bis(1,2,4-triazol-5-one) (ZTO) and its solvent adducts have been reported, and the single crystal X-ray measurements indicated that the ZTO crystals...     

旋涂法制备PEO-PAN-PMMA三组分共混凝胶聚合物电解质

随着新能源产业和储能产业的快速发展,二次电池的安全性和能量密度要求越来越高.而传统的液态锂电池使用易燃的电解液,所以存在较大的安全隐患.因此固态锂电池由于其较高的安全性和能量密度受到越来越多人的关注.目前困扰固态电池应用的主要问题是其离子电导率和电极电解质界面问题.固态电解质是固态电池的关键材料.因此开发高离子电导率的固态电解质是开发固态电池的关键.在本工作中,作者成功通过旋涂法制备聚乙二醇-聚丙烯腈-聚甲基丙烯酸甲酯（PEO-PAN-PMMA）凝胶电解质.PEO-PAN-PMMA聚合物薄膜为均匀透明的,具有较高的吸附率,且热稳定性较好,在380℃下保持稳定.通过浸泡电解液可以得到性能优异的凝胶电解质.该凝胶电解质具有较高的离子电导率,室温离子电导率为0.4 mS/cm,而且电化学窗口较宽,在0～4.2 V之间化学性能较为稳定,界面稳定性较好.组装成Li//PEO-PAN-PMMA凝胶电解质//LiCoO₂电池之后,正极首圈放电容量为129.8 mAh/g,循环100周,正极放电容量剩余119.51 mAh/g,在0.1 C、0.2 C、0.5 C和1 C倍率下循环,正极放电容量分别为129.8 mAh/g,99.5 mAh/g,86.1 mAh/g和64 mAh/g.     

采用氧合血红蛋白吸收带的漫反射光谱比率R540/R575检测人胃癌

采用氧合血红蛋白吸收带的平均漫反射光谱比率(R540/R575)对离体的人正常胃、未分化胃腺癌、胃鳞状细胞癌和低分化胃腺癌的上皮粘膜组织进行鉴别诊断.实验采用带积分球附件的分光光度计测量组织样品在400 nm～600 nm的漫反射光谱.实验结果表明,在相同的波长范围内,人的未分化胃腺癌、胃鳞状细胞癌和低分化胃腺癌的上皮粘膜组织的漫反射光的强度较人正常胃的上皮粘膜组织的漫反射光强度要显著地低的,尤其是在氧合血红蛋白的吸收带540 nm和575 nm波长处,人正常胃、未分化胃腺癌、胃鳞状细胞癌和低分化胃腺癌的上皮粘膜组织的平均漫反射光谱比率分别是(94.25±2.4)%,(109±3.0)%,(1032±2.8)%和(98.6±2.6)%.