反相高效液相色谱法分离测定复合维生素片剂中VB1,VB2,VB6和烟酰胺

采用NovaPak C18色谱柱(30 cm×3.9 mm,粒径10 μm),以(V(水)V(甲醇)V(冰乙酸)m(庚烷磺酸钠)=730 mL270 mL5 mL400 mg)为流动相,检测波长为280 nm,分离测定了复合维生素片剂中的VB1,VB2,VB6和烟酰胺,实验回收率分别为100.5%,96.8%,98.1%,102.0%,相对标准偏差RSD分别为0.8%,0.4%,0.5%,1.2%(n=5),检出限分别为39,4.2,4.7,10 ng.本法已用于复合维生素片剂中VB1,VB2,VB6和烟酰胺的分离和测定.     

基于扰动模糊综合评价法的企业BI项目实施风险评估研究

商业智能(BI)系统能够帮助企业经营者进行智能化的决策,但在一个日益复杂的企业运营环境中,BI系统的实施如同ERP系统一样,面临着巨大的问题、压力和高风险.针对以上特性,提出了一种BI项目实施风险扰动模糊综合评价模型和方法,以上海新媒体A公司的BI项目为实例对企业BI项目实施中的各相关风险因素进行了分析,最优判别,得出了导致风险的主要因素,同时为BI实施风险规避策略提供科学依据.     

Vapor generation – atomic spectrometric techniques. Expanding frontiers through specific-species preconcentration. A review

We review recent progress in preconcentration strategies associated to vapor generation techniques coupled to atomic spectrometric (VGT-AS) for specific chemical species detection. This discussion focuses on the central role of different preconcentration approaches, both before and after VG process. The former was based on the classical solid phase and liquid–liquid extraction procedures which, aided by automation and miniaturization strategies, have strengthened the role of VGT-AS in several research fields including environmental, clinical, and others. We then examine some of the new vapor trapping strategies (atom-trapping, hydride trapping, cryotrapping) that entail improvements in selectivity through interference elimination, but also they allow reaching ultra-low detection limits for a large number of chemical species generated in conventional VG systems, including complete separation of several species of the same element. This review covers more than 100 bibliographic references from 2009 up to date, found in SCOPUS database and in individual searches in specific journals. We finally conclude by giving some outlook on future directions of this field.     

基于χ~2检验法的通脑活络针刺法对脑梗死患者BI指数的影响

用r×s列连表的Pearson x~2检验法,讨论通脑活络针刺法、溶栓剂法与常规法在各救治时间窗对脑梗死患者BI评分的影响,并得到结论,通脑活络针刺法在各救治时间窗的"治愈率"及较好的康复程度方面显示了显著疗效.     

县域区域旅游整体形象设计--以余姚市为例

旅游空间要素的组合以点、线、面为其基本特征，因此区域旅游形象设计在新时期日益受到各方重视．以余姚市为例，通过对影响余姚市旅游形象主要因素的分析，运用旅游形象设计的理论和方法，构建了一个包括整体形象、理念基础、行为形象、视觉形象等在内较为全面的旅游形象系统，从而完成了对县域区域的旅游整体形象设计基础研究．     

On-line sample processing involving microextraction techniques as a front-end to atomic spectrometric detection for trace metal assays: A review

Within the last decade, liquid-phase microextraction (LPME) and micro-solid phase extraction (μSPE) approaches have emerged as substitutes for conventional sample processing procedures for trace metal assays within the framework of green chemistry. This review surveys the progress of the state of the art in simplification and automation of microextraction approaches by harnessing to the various generations of flow injection (FI) as a front end to atomic absorption spectrometry (AAS), atomic fluorescence spectrometry (AFS) or inductively coupled plasma atomic emission spectrometry or mass spectrometry (ICP-AES/MS). It highlights the evolution of flow injection analysis and related techniques as vehicles for appropriate sample presentation to the detector and expedient on-line matrix separation and pre-concentration of trace levels of metals in troublesome matrices. Rather than being comprehensive this review is aimed at outlining the pros and cons via representative examples of recent attempts in automating green sample preparation procedures in an FI or sequential injection (SI) mode capitalizing on single-drop microextraction, dispersive liquid-phase microextraction and advanced sorptive materials including carbon and metal oxide nanoparticles, ion imprinted polymers, superparamagnetic nanomaterials and biological/biomass sorbents. Current challenges in the field are identified and the synergetic combination of flow analysis, nanotechnology and metal-tagged biomolecule detection is envisaged.     

Effects of ultrasonic treatment on color,carotenoid content,enzyme activity,rheological properties,and microstructure of pumpkin juice during storage

Freshly squeezed pumpkin juice (Cucurbita moschata D.) was sonicated at various power levels at a constant frequency of 25 kHz and a treatment time of 10 min. Samples were stored in the dark for 0, 4, 8, and 12 days at 4 °C and were subsequently analyzed. The combined effects of power level and storage period on color parameters, carotenoid content, particle size distribution, cloud value, rheological characteristics, and microstructure were investigated. The results showed ultrasonic-treated samples had little effect on carotenoid content, cloud value, particle size distribution, and polydispersity during storage compared to those of the untreated samples. The L^⁎, a^⁎, b^⁎, and C* values decreased significantly during 8–12 days of storage, resulting in a significant increase in ΔE, especially 400 W/10 min-treated samples. Meanwhile, the enzyme activity and rheological properties increased significantly on storage days 8–12. However, the microstructure of all samples did not change significantly during storage. Based on these results, during the storage period, the physical and chemical properties of 400 W/10 min-ultrasonic treated pumpkin juice were retained more than those in the untreated pumpkin juice. Therefore, ultrasonic treatment has broad application prospects in preserving bioactive substances and physicochemical properties and improving the storage life of fresh pumpkin juice.     

Anisotropic Cosmological Models with Perfect Fluid and Dark Energy Reexamined

We consider a self consistent system of Bianchi type-I (BI) gravitational field and a binary mixture of perfect fluid and dark energy. The perfect fluid is taken to be the one obeying the usual equation of state, i.e., p = ξε, with ζ∉[0, 1] whereas, the dark energy is considered to be obeying a quintessence-like equation of state. The modification of the ordinary quintessence lies in the fact that its pressure becomes positive if the (dark) energy density exceeds some critical value. Exact solutions to the corresponding Einstein equations are obtained. The model in consideration gives rise to a Universe which is spatially finite. Depending on the choice of problem parameters the Universe is either close with a space-time singularity, or an open one which is oscillatory, regular and infinite in time. PACS numbers: 04.20.Ha, 03.65.Pm, 04.20.Jb     

滇桂艾纳香水溶性多糖BRP-B的分离纯化及止血活性

用蒸馏水溶解滇桂艾纳香浸膏,从中提取多糖,通过膜分离、三氯乙酸法脱蛋白、二乙氨基乙基(DEAE)脱色、SephadexG10、SephadexG50凝胶柱色谱纯化,获得滇桂艾纳香水溶性多糖(BRP-B)。 由凝胶渗透色谱（HPGPC）确定BRP-B为相对分子质量分布均一的多糖,其数均分子量和质均分子量分别为2654和2716 Da。 以血浆复钙时间（PRT）为指标,研究BRP-B的凝血活性,结果显示BRP-B质量浓度为6.25×10-2 g/L时,凝血时间为248.52 s,凝血时间抑制率达22.42%。 小白鼠离体子宫实验结果显示,BRP-B质量浓度为1.67×10-2、1.97×10-2及2.85×10-2 g/L时能明显增加子宫平滑肌的收缩频率。