大鼠肾脏糖胺聚糖的种类及二糖组成分析

采用两步酶解和离子交换色谱从Wistar大鼠肾脏中提取糖胺聚糖,以醋酸纤维素薄膜电泳分析糖胺聚糖种类,以弱阴离子交换色谱分离各种糖胺聚糖.纯化后的糖胺聚糖分别经特定糖胺聚糖酶裂解,采用强阴离子交换高效液相色谱(SAX-HPLC)紫外检测分析其二糖组成.结果表明,Wistar大鼠肾脏糖胺聚糖主要由硫酸乙酰肝素和少量硫酸皮肤素组成.硫酸乙酰肝素含有8种二糖,其中含有乙酰基二糖总含量高达77.6%,非硫酸化二糖(Ⅳ-A)含量为59.7%;硫酸皮肤素含有6种二糖,其中单硫酸化二糖总含量为54.8%,非硫酸化二糖含量为32.9%.     

Optimal design of a multilayer diffractive optical element for dual wavebands

A method for optimal design of a multilayer diffractive optical element (MLDOE) for dual-wide-waveband optical systems is presented with consideration of polychromatic integral diffraction efficiency (PIDE) and the weight factors of PIDE for each waveband. The design process and simulation of a MLDOE in mid-wave and long-wave IR are described, and the comparison of diffraction efficiency of the MLDOEs for different design wavelength pairs determined by different methods is given. This method can make the design process more rational and more reasonable and can give a better design result than that with the conventional design method.     

Thermo-optically tunable silicon photonic crystal light modulator

We designed, fabricated, and characterized a thermo-optically tunable compact (10 μm × 10 μm) silicon photonic crystal (PhC) light modulator that operates at around 1.55 μm for TE polarization. The operational principle of the device is the modulation of the cutoff frequency in a silicon-based line defect PhC. The cutoff frequency is shifted because of the thermo-optic tuning of the silicon refractive index, which is realized by localized heating on the PhC. The modulator is formed by a triangular lattice array of cylindrical air holes on a silicon-on-insulator wafer. Optical characterization was carried out, and the result clearly showed thermo-optic tuning of the cutoff frequency at around 1.55 μm.     

代数迭代法用于傅里叶变换计算层析成像光谱仪数据重建

主要介绍代数迭代法在傅里叶变换计算层析成像光谱仪数据处理中的应用。根据4种不同投影数进行了光谱切片重建,并对光谱相似性进行了比较。针对ART算法可应用少数投影重建的特点,专门在45个投影数时,采用不同迭代系数进行了重建,并进行了比较。最后,对实际场景进行了光谱切片重建。     

Characteristics of Raman spectra of natural clinochlore at 200 degrees C and 0.95-7.70 GPa

Variation of crystal structure of natural clinochlore with pressure was investigated by the approach of diamond anvil cell (DAC) and in situ micro-Raman spectroscopic measurement at 200 degrees C and up to 7.7 GPa. The 481 and 786 cm(-1) peaks shift towards high-frequency linearly with increasing pressure at 200 degrees C. The linear relations between Raman shift (N, cm(-1)) and pressure (P, GPa) for the two peaks are: N = 11.136P+482.6 (R2 = 0.987 4) and N = 5.055P+785.7 (R2 = 0.983 7), respectively. The 865 cm(-1) peak arising from the stretching mode of the Si-O(nb) shifts slightly because of the strong repulsion between T cations at the tetrahedral sites and M cations at the octahedral sites in the TOT layer. Raman shift of 481 cm(-1) and 786 means the shortening of the length of M-O(br) and Si-CO(br) bonds since the peaks are contributed by the stretching mode of the M-O(br) and Si-O(br) respectively. No phase transition of clinochlore under the experimental condition was found. The results indicate that chlorite minerals may be stable at least at a depth of 80-90 km in the cold subduction zones, and the fluid derived from chlorite dehydration may be an important fact for earthquake occurrence in the subduction zones.     

Layer-by-layer assembled multilayer films of methoxypoly(ethylene glycol)-block-poly(α,l-glutamic acid) and chitosan with reduced cell adhesion

A methoxypoly(ethylene glycol)-block-poly(α,L-glutamic acid) (mPEGGA) diblock copolymer is synthesized. Using QCM measurements, it is shown that (CS/mPEGGA)(n) film construction takes place over two build-up stages (exponential-to-linear). UV-vis spectra reveal the regular increase of the multilayer film growth at different molecular weights of mPEGGA. Contact angle and surface morphology investigation prove that the hydrophilicity of CS/mPEGGA multilayer film-modified substrate becomes better and the surface becomes rough. Significantly reduced cell adhesion is observed on the CS/mPEGGA multilayer film coated surface.     

Microbial transformation of deoxyandrographolide by Alternaria alternata AS 3.4578

Biotransformation of deoxyandrographolide (1) by Alternaria alternata AS 3.4578 gave five derivatives identified by spectral methods including 2D NMR as the known dehydroandrographolide (2) and 9beta-hydroxy-dehydroandrographolide (3) and the new compounds 9beta-hydroxy-deoxyandrographolide (4), 3alpha,17,19-trihydroxy-8,13-ent-labdadien-15,16-olide (5) and 3-oxo-9beta-hydroxy-deoxyandrographolide (6).     

Convergence behavior of Gauss–Newton’s method and extensions of the Smale point estimate theory

The notions of Lipschitz conditions with L$L$ average are introduced to the study of convergence analysis of Gauss–Newton’s method for singular systems of equations. Unified convergence criteria ensuring the convergence of Gauss–Newton’s method for one kind of singular systems of equations with constant rank derivatives are established and unified estimates of radii of convergence balls are also obtained. Applications to some special cases such as the Kantorovich type conditions, γ$\gamma$-conditions and the Smale point estimate theory are provided and some important known results are extended and/or improved.     

Superparamagnetic mesoporous Mg-Fe bi-metal oxides as efficient magnetic solid-base catalysts for Knoevenagel condensations

Superparamagnetic mesoporous Mg-Fe bi-metal oxides with varied Mg-Fe atomic ratios have been successfully synthesized as solid base catalysts. The M2F-400 catalyst with Mg/Fe atomic ratio = 2 showed extraordinarily high activities for Knoevenagel reactions even at room temperature. It could be magnetically separated, recycled, and reused for at least five cycles.