头孢噻甲羧肟的伏安行为及其单扫描极谱法测定

以多种电化学手段研究了头孢噻甲羧肟的伏安行为。在磷酸盐缓冲溶液中，ＣＴＤ产生２个不可逆吸附还原波，峰电位分别为－０．６５Ｖ和－１．２０Ｖ。分别有１个电子与２个电子和１个质子参与了峰１与峰２的电极过程。探讨了电极反应机理。     

Studies on synthesis and properties of poly(ferrocenyldimethylsilanes) and poly(ferrocenylmethylphenylsilanes)

Poly(ferrocenyldimethylsilane) and poly(ferrocenylmethylphenylsilane) have been prepared via the thermal ring-opening polymerization of the corresponding strained, silicon-bridged ferrocenophanes. It was found that the molecular weights of resultant polymers depend on the polymerization time. Their electrochemical behavior in aqueous electrolytes was investigated by cyclic voltammetry.     

Electrochemical studies of reaction of ciprofloxcin and DNA

The electrochemical behavior of ciprofloxacin (CFX) and its interaction with the natural calf thymus DNA (ctDNA) is studied by using pulse difference voltammetry on a carbon electrode. CFX shows a well-defined oxidative peak at + 0.88 V. As a result of reaction with ctDNA,the oxidative peak of CFX decreased markedly. According to the electrochemical equation deduced in this paper, the binding constant of 1.36 × 10⁵ (mol/L)⁻¹ and the binding size of 1.94 (base pairs) of CFX with ctDNA were obtained by nonlinear fit analysis of the electrochemical data. The mechanism of the interaction was explored. __________ Translated from Journal of Zhejiang University (Science Edition), 2007, 34(3): 330–334 [译自: 浙江大学学报(自然科学版)]     

Engineering of Self-assembly Polymers Encapsulated with Dual Anticancer Drugs for the Treatment of Endometrial Cancer

Chemotherapy side effects are minimized, and therapeutic results are enhanced by combination therapy, which is extensively utilized in cancer therapy. MTT experiment showed that compared to the free drugs calreticulin (CRT) and gemcitabine (GEM), GEM-CRT@NPs significantly increased the cytotoxicity of endometrial cancer (Ishikawa cells and KLE cells). These drugs were conjugated to a tri-block copolymeric framework. GEM-CRT@NPs were studied using HR-TEM and DLS analysis to determine particle size and zeta potential. Biochemical staining analyses were also used to investigate the morphological characteristics of endometrial cancer cell lines. After KLE and Ishikawa cancer cells were treated with GEM-CRT@NPs, endometrial cell shape was altered, as evidenced by nuclear fragmentation and nuclear condensation (apoptosis hallmarks). Additionally, the most significant apoptosis ratio to mitochondrial membrane potential indicates that the mitochondrial membrane potential is responsible for the cell's death. Upon treatment with GEM-CRT@NPs, systemic toxicity analysis revealed minimal histological abnormalities and significant blood chemistry alterations, and a near-normal look of the organs. Endometrial cancer treatment may be enhanced with the use of the targeted combination therapeutic system.

     

T型微通道内溶胶液滴形成过程

以制备空心玻璃微球的前体溶胶和硅油为原料,采用实验观测和数值模拟的方法,对T型微通道内溶胶乳液形成过程进行研究。基于液滴的受力分析,建立了液滴形成过程的数学模型,探讨了液滴大小的变化规律。研究结果表明:对于给定的物料体系和T型微通道,通过改变两相流量可以有效地控制液滴尺寸;在相同的分散相流量条件下,增大连续相流量可以减小液滴尺寸,但连续相流量大到一定程度后,这种效果逐渐减弱;在给定的连续相流量条件下,分散相流量越大,液滴直径越大;利用数学模型计算出的液滴直径与实验值偏差在10%左右。根据模拟结果和摄像分析,液滴产生过程经历了静态长大和缩颈剥离两个主要阶段。     

搅拌法制备聚合物微球中油水相对壁厚的影响

为了研究乳液微封装技术中油水相对微球壁厚的影响,推导了在理想状态下微球壁厚、油相质量分数和油水相比这三者之间的函数关系。结果表明:当内相水滴半径和油相质量分数为常数时,微球壁厚是油水相比的单增函数;而当内相水滴半径和油水相比为常数时,微球壁厚是油相质量分数的单增函数。即提高油相质量分数或增大油水相比对增加壁厚而言具有等效性。根据此规律,在搅拌法制备小直径聚苯乙烯微球中,通过调整油水相的各参数,确定了制备小直径厚壁聚苯乙烯微球的关键工艺参数。实验表明:采用搅拌法制备10~25 m壁厚的小直径聚苯乙烯微球时,油相质量分数宜配制为5.3%~7.0%,油水相比宜控制在1.6~2.2之间,而外水相中聚乙烯醇质量分数宜控制在1%~3%之内。     

激光惯性约束聚变靶靶丸制备与表征

激光惯性约束聚变的核心思想是利用球形内爆技术对聚变燃料进行增压,使热核燃料达到高温、高密度的等离子体状态,进而实现聚变点火。基于对称压缩、流体界面不稳定性和实验诊断的考虑,ICF实验对作为热核燃料容器的空心微球的品质在球形度、壁厚均匀性、表面粗糙度以及掺杂水平等方面提出了严格的要求。为满足这些要求,陆续发展了乳液微封装技术、降解芯轴技术、低压等离子体聚合/掺杂技术、干凝胶玻璃微球制备技术等用于多层塑料微球和空心玻璃微球的研制。另一方面,针对ICF靶丸量小、质轻以及表面要求高的特点,发展了相应的非破坏性靶丸参数表征技术,如X光照相技术、4π形貌表征技术、微球掺杂水平测量技术以及微球内燃料负载水平快速测试技术。基于这些制备与表征技术,初步实现了多层塑料微球、玻璃微球、聚-!-甲基苯乙烯芯轴微球、梯度掺杂CH微球的研制,满足了"神光Ⅱ"、"神光Ⅲ原型"及"神光Ⅲ主机"上开展的一系列内爆物理实验的要求,同时为未来点火物理实验用靶丸的研制提供了技术支撑。     

Realization of Absolute‐Phase Unwrapping and Speckle Suppression in Laser Digital Holography

In this paper, an absolute‐phase unwrapping and speckle suppression approach to reconstruct a three‐dimensional (3‐D) image of an object with laser digital holography is described. This method offers three advantages to enhance the performance of the phase reconstruction technique. First, both speckle suppression and phase unwrapping are processed in the complex amplitude domain rather than in the single phase or amplitude domain. With this approach, the phase details of the object are better preserved upon phase reconstruction. Second, the proposed algorithm requires no threshold determination and thus achieves self‐adaptive speckle suppression and robust phase unwrapping, in contrast to other methods. Finally, an improved dual‐domain image denoising method is applied to further remove speckle‐remnant‐induced phase distortion. Ideal 3‐D phase reconstruction results are obtained both theoretically and experimentally for the first time.     

引导性笔记在电类专业基础课教学中的应用

总结了引导性笔记在国内外课程教学中的应用情况和积极作用,以《电路》和《信号与系统》等电类专业基础课教学为例,论证了引导性笔记这种课堂辅助教学模式的具体实施办法,将引导性笔记纳入课程教学的形成性评价体系,侧重于工程应用和对元认知问题的解决.研究结果表明,采用引导性笔记可使学生的预习更具有针对性和方向性,有助于提升课堂笔记的完整性和深度,进而提高课堂学习效率和课程学习效果.也可以使得教师教学更加系统、有序和高效,具有积极意义和可推广价值.     

Preparation of ionic liquid‐modified magnetic nanoparticles based on thiol‐ene click chemistry for the analysis of polycyclic aromatic hydrocarbons in water and smoked meat samples

In the present study, ionic liquid (IL)‐modified Fe₃O₄ magnetic nanoparticles (Fe₃O₄) were synthesized by the thiol‐ene click reaction for magnetic solid‐phase extraction (MSPE) of polycyclic aromatic hydrocarbons (PAHs) in water and smoked meat samples. An IL 1‐vinyl‐3‐butylimidazolium bromide was firstly synthesized, and then immobilized on the surface of thiol group‐functionalized Fe₃O₄ via a thiol‐ene click reaction. The as‐synthesized Fe₃O₄@ILs were characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, and transmission electron microscopy. Various parameters (including the amount of adsorbent, extraction time, sample volume, and desorption conditions) affecting MSPE were optimized. Under the optimum conditions, the limits of detection of four PAHs in the range of 0.6–7.2 ng/L were obtained using high‐performance liquid chromatography–ultraviolet detection. The accuracy of the method was assessed by recovery measurements on spiked real samples and good recovery of 80–108% with relative standard deviations lower than 8.16% was achieved. The enrichment factors ranging from 699 to 858 were obtained for the analytes. This result indicated that the proposed method had great potential for sample preparation.