紫外激光诱导胃癌组织自体荧光的研究

本文测量了紫外激光（３０８ｎｍ）激发诱导正常组织和胃癌组织３１５ｎｍ－６００ｎｍ波段的自体荧光，发现胃癌组织在此荧光光谱不同于正常组织的荧光光谱。根据两者４的区别，可以把胃癌组织从正常组织中区分出来，这为诊断胃癌提供了一个新的思路。     

A numerical investigation on the geometry dependence of the crack growth resistance in CT specimens

The influence of the specimen thickness B and the ligament length b on the J _R -curves is numerically investigated for CT specimens. The thickness effect is taken into account with 2-D analyses by dividing a plain sided specimen into a plane stress part and a plane strain part. The fracture process is controlled by experimentally determined critical values of the crack tip opening displacement for crack growth initiation (CTOD_i) and the crack tip opening angle for stable crack growth (CTOA_C). It is shown that for the global behaviour of a plain sided specimen, the B/b ratio is essential. The difference between the geometry dependence of the initiation value of the J-integral and the geometry dependence of the slope of the J _R -curves is also shown.     

一种高速浮点加法器的设计实现

浮点加法器是协处理器的核心运算部件，是实现浮点指令各种运算的基础，其设计优化是提高浮点运算速度和精度的关键途径。文章从浮点加法器算法和电路实现的角度给出设计方法，并且提出动态与静态结合设计进位链的方案以及前导O预测面积与速度的折衷方法。动态与静态结合设计进位链的方法有效地降低了功耗，提高了速度，改善了性能。目前已经嵌入协处理器的设计中，并且流片测试成功。     

由三面投影图生成三维立体图的方法研究

针对创新设计中零部件的三维虚拟造型问题，提出了一种由二维投影图生成三维立体图的计算机化辨识方法。通过辨识简单三维立体的形状和空间位置，克服了二维图形中面的积聚性和零件之间不规则相贯和截交曲线的识别问题，进而实现了复杂组合形体的计算机化设计与造型。最后，以箱体类零件为例，在AutoCAD环境下利用VC 和ObiectARX开发工具编程验证了该方法的有效性。     

添加剂强化重油催化裂化的过程分析与应用

运用工程化学原理分析讨论了添加剂强化重油催化裂化的过程，包括分散稳定气泡、改善雾化、保护酸中心、抑制焦炭生成以及提高重油气化率的胶体结构改性、降低表面张力和改善微孔润湿，并用以指导强化重油催化裂化添加剂的筛选。建立小型固定流化床催化裂化实验装置评价了添加剂的强化效果。结果表明，添加剂强化重油催化裂化可降低催化剂生焦1．0％左右，提高总液体收率1．0％～2．8％。     

N,N′-二(β-十八酰氧基)乙基乙二胺二乙酸钠的合成及性能研究

用 N,N′-二羟乙基乙二胺、氯乙酸钠合成了 N,N′-二羟乙基乙二胺二乙酸钠(中间体),中间体再与硬脂酰氯反应制备了一种新型 Gemini 两性表面活性剂 N,N′-二(β-十八酰氧基)乙基乙二胺二乙酸钠。对产物合成条件进行了考察,优化的反应条件为:n(硬脂酰氯):n(中间体)=2.5,溶剂 V(水):V(氯仿)=1:2,pH=9.0～10.0,反应温度15～20℃,反应时间5 h。通过红外光谱和质谱分析确定了产物结构,并测试了产物的表面性能。结果表明,在25℃时,该产物的临界胶束浓度为0.24 mmol/L,临界胶束浓度下的表面张力为35.7 mN/m;即时泡沫高度为250 mm,5 min 后泡沫高度为220 mm;乳化时间为22.48 min(甲苯-水物系)和4.65 min(正己烷-水物系),亲水-亲油平衡值为5.4,等电点为 pH 3.3～6.5。     

Epoxidation of high trans‐1,4‐polyisoprene and its properties

A new organic‐solvent‐free water‐phase suspension method was used to synthesize partially epoxidized high trans‐1,4‐polyisoprene (TPI) to improve its properties, including oil resistance and wet‐skid resistance. The epoxidation was conducted in an aqueous peracetic acid solution and on the TPI granules prepared by a bulk precipitation method with supported titanium catalyst. The effects of the synthesis conditions, including reaction temperature, reaction time, and pH value, on the epoxy content were investigated. Epoxidized trans‐1,4‐polyisoprene (ETPI) with epoxy contents between 10 and 80% were obtained within 4 h. Both the amorphous and crystalline regions of TPI were epoxidized. The crystallization properties decreased with increasing epoxy content. ETPIs possessed lower mechanical properties than TPI but could be enhanced by vulcanization. The oil resistance and wet‐skid resistance were significantly improved after epoxidation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Synthesis and characterization of a novel proton‐exchange membrane for fuel cells operating at high temperatures and low humidities

The synthesis of a p‐toluidine/formaldehyde (PTF) resin was performed, and the effects of the molar ratio of the individual monomers and the polymerization conditions on the structure of the PTF resin were studied. Fourier transform infrared and ¹³C‐NMR spectra were used to characterize the PTF. Wide‐angle X‐ray diffraction patterns revealed the crystalline structures of various PTFs. Polarized optical microscopy revealed that the molar ratio of the monomers had a strong effect on the crystalline morphologies. A longer polymerization time turned out a polymer with a higher intrinsic viscosity and molecular weight, which led to differences in the proton conductivity. All of the PTFs showed a higher proton conductivity than a commercial Nafion membrane at 90–100°C and 0% relative humidity. The proton conductivity of the PTF series could be improved by sulfonation with sulfuric acid and could be maintained after blending with polyurethane. Pure methanol could be used as a fuel source because of the insolubility and nonwetting properties of PTF in methanol to increase the output current density for a PTF membrane electrode assembly. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008