微波消解-氢化物发生-原子荧光光谱法测定7种中草药中砷

利用原子荧光光谱法测定7种驱虫类中草药中的砷.实验采用微波消解样品,以盐酸为测定介质,硫脲-抗坏血酸为预还原剂,硼氢化钾为氢化剂,用氢化物发生-原子荧光光谱法测定砷含量.砷含量在10-100ng/mL浓度范围内线性关系好(r2=0.9924).回收率为93.83%-110.94%之间.方法简便、快速、灵敏、准确,可用于中草药中砷的测定.     

SBIRS-HIGH对导弹上升段位置测量精度及中末段位置预报精度的分析

根据目前的技术水平分析了高空天基红外系统(SBIRS-HIGH)的技术参数;理论上计算了SBIRS-HIGH对导弹上升段的位置测量精度以及中末段任意时刻飞行位置的预报精度;研究了SBIRS-HIGH对中段和末端导弹拦截系统的导引能力。     

微振动光电检测与数据采集系统的设计

提出了一种新的光学非接触式测量方法测量了物体的微振动振幅。用激光作为光源,以四象限硅光电池[1]作为光电探测器,借助三角测量原理,投射在振动源表面的激光反射光束在光电探测器上产生平面位移,将位移信号放大,通过A/D模块采集电压数值,并通过串口通信机制在PC终端实时显示。实验结果表明,该方法原理正确,灵敏度高,便于实现连续、快速、自动化检测,在工业在线检测方面具有良好的应用前景。     

Two-dimensional Anhydrous Cadmium(II) Phthalate

The in situ hydrolysis of phthalyl-γ-glutaminyl-histidine with Cd(ClO₄)₂·6H₂O in the presence of water and methanol affords a novel two-dimensional cadmium coordination polymer, a new phase, anhydrous cadmium(II) phthalate, ( 1 ). The structure was determined by single crystal X-ray diffraction. Crystal data: P2₁/c, a = 13.8168(14), b = 7.0351(7), c = 8.2054(8) Å, β = 105.540(2)°, V = 768.43(13) ų, Z = 4, R₁ = 0.0380, wR₂ = 0.1111.     

Development in Synthesis,Electrochemistry, LB Moieties of Phenothiazine Based Units

A convenient and higher yielding synthetic route to N‐alkyl‐bis(thiophene)phenothiazine derivatives is reported and their aggregation, electrochemical properties and polymerization are characterized. The key step in the synthesis of this group of compounds has been the Stille type coupling reaction between the N‐alkyldibromophenothiazine and tin derivatives of thiophene as the best way for preparation of conjugated N‐alkylphenothiazine derivatives. For this group of compounds we also present an electrochemical polymerization effect and widely adopted approach to prepare structurally ordered thin, electroconducting films by Langmuir–Blodgett technique.     

Characterization of a 4-miktoarm star copolymer of the (PS-b-PI)3 PS type by temperature gradient interaction chromatography

Temperature gradient interaction chromatography (TGIC) was applied for the separation of a complex miktoarm star copolymer which has one polystyrene (PS) arm and three polystyrene-b-polyisoprene (PS-b-PI) diblock copolymer arms. Such miktoarm star polymers are much more difficult to characterize than branched homopolymers since the byproduct, typically polymers with missing arm(s) or coupled products, have not only different molecular weights but also different compositions. TGIC was able to fully separate the byproducts, and the composition of the molecular species corresponding to the different separated elution peaks was determined by two methods, fractionation/NMR and multiple detection (UV and RI). A reasonable agreement between the results of the two methods was obtained. By using the composition found, the corresponding molecular weights were determined by multi-angle light scattering detection. Based on the composition and the molecular weight we were able to identify the structure of the different molecular species.     

An N,N′-diaryl urea based conjugated polymer model system

An N,N′-diphenyl urea was designed as a model system for aggregation phenomenon in poly(phenyleneethynylenes) (PPEs). The unmethylated N,N′-diphenyl urea adopts an open, unfolded conformation in which the two diphenyl acetylene fluorophores are far enough away, mimicking the unaggregated state. Dimethylation forces the aromatic surfaces together into π-π contact, mimicking the aggregated state of PPEs. Analogous to bulk PPEs, this model system shows dramatic differences in quantum yield between the folded and unfolded states, with the unfolded urea having greater than 400-fold higher fluorescence quantum yield than its folded equivalent.     

Fluorescent oligonucleotide incorporating 5-(1-ethynylpyrenyl)-2-deoxyuridine: sequence-specific fluorescence changes upon duplex formation

We describe the design and properties of a pyrene-labeled deoxyuridine that can be inserted efficiently into oligodeoxynucleotides using phosphoramidite chemistry. An oligonucleotide incorporating the pyrene-labeled deoxyuridine is a sensitive fluorescence probe that can discriminate between perfect and single-base-mismatched pairing by changes in its fluorescence intensity.     

UP-conversion of terahertz radiation induced by photon drag effect

An all-optical approach to convert terahertz radiation (THz, wavelength λ₁) into infrared (IR, peak wavelength λ₂) is presented. We show that this up-conversion process is due to the photon drag effect induced by the THz radiation in intrinsic narrow-gap semiconductors followed by spatial redistribution of current carriers and band-to-band radiative recombination. The process results in non-selective high-speed (ns range rise/fall times) IR imaging of positive (conventional luminescence) and/or negative (negative luminescence) contrasts. Estimates made for an InSb pixelless converter at 300 K and moderate THz intensity (kW/cm²) show that this up-conversion process (with λ₁/λ₂>10²) can be observed with a conventional thermal imaging camera.     

基于虚拟仪器的人体皮肤组织吸收光谱检测平台

本文运用光电无损检测技术,采用皮外反射式测量方法,通过光纤光谱仪和虚拟仪器构建人体皮肤组织吸收光谱检测平台.该平台适合于光子-组织相互作用基础研究及激光美容临床检测,可协助医师进行病理诊断和病变程度判别.文中给出几个吸收光谱的检测结果.