金衢盆地加积型红土地球化学特征

金衢盆地广泛分布着不同类型的第四纪红土。通过X射线荧光光谱法（XRF）对金衢盆地的85个样品进行了测试。结果表明：（1）主量元素组成以SiO2、Fe2O3、Al2O3为主,K、Na、Ca、Mg等易溶组分的含量很低,TiO2含量的平均值高于UCC值;（2）MnO含量在网纹红土和均质红土的交界处明显聚集,推测与不同沉积物交界处理化性质突变有关;（3）在剖面上,SiO2、Fe2O3、AkO3等化学成分和硅铝率沿剖面变化的趋势,以及基岩和上覆沉积层的元素组成、化学风化指标和Ti／Zr的区别,均表明所研究的金衢盆地红土剖面具有较好的相似性,与典型的岩石风化壳存在明显差别。     

应变率对含裂隙红砂岩裂纹扩展模式及破碎特征的影响

以含不同倾角预制裂纹的长方形板状红砂岩为研究对象,采用分离式霍普金森压杆沿试样宽度方向施加冲击荷载,使用高速摄像机记录裂纹扩展过程,获得试样的裂纹路径特征以及动态压缩强度和动态弹性模量,利用筛分统计法分析试样碎块分布特征,结合分形理论定量描述试样破碎程度及特点,探讨中应变率条件下含裂隙试样裂纹扩展模式与动态力学性质和破碎程度的相互关系。研究结果表明,应变率较高时试样会更多地出现远场裂纹和离层裂纹,并且相比相关低应变率实验结果,中应变率范围内试样破坏模式及裂纹分布情况随应变率的变化规律是不同的。随着应变率的提高,试样大体上从1条拉伸裂纹的临界破坏演变成X形剪切裂纹为主的复杂裂隙网络,并且不同角度预制裂隙对于这种裂纹扩展模式的演变有重要影响。在预制裂纹倾角一定的情况下,岩样动态压缩强度和动态弹性模量表现出明显的应变率效应,不同角度预制裂纹对于试样的应变率敏感性有显著影响。随裂纹倾角的增大,试样的动态强度、动态弹性模量和分形维数表现出的变化趋势具有一定的相似性,大体呈现先减小后增大的趋势,裂纹倾角为45°的试样的动态压缩强度、动态弹性模量和分形维数均为最小。随应变率的升高,不同预制裂纹倾角的试样碎块分布更加分散,应变率越高,预制裂纹倾角对于岩石冲击破碎程度、分形维数的影响越显著。

     

Dihydrogen Bonding—Seen through the Eyes of Vibrational Spectroscopy

In this work, we analyzed five groups of different dihydrogen bonding interactions and hydrogen clusters with an H3+ kernel utilizing the local vibrational mode theory, developed by our group, complemented with the Quantum Theory of Atoms–in–Molecules analysis to assess the strength and nature of the dihydrogen bonds in these systems. We could show that the intrinsic strength of the dihydrogen bonds investigated is primarily related to the protonic bond as opposed to the hydridic bond; thus, this should be the region of focus when designing dihydrogen bonded complexes with a particular strength. We could also show that the popular discussion of the blue/red shifts of dihydrogen bonding based on the normal mode frequencies is hampered from mode–mode coupling and that a blue/red shift discussion based on local mode frequencies is more meaningful. Based on the bond analysis of the H3+(H2)n systems, we conclude that the bond strength in these crystal–like structures makes them interesting for potential hydrogen storage applications.     

薄层色谱-紫外可见分光光度法测定食品中的苏丹红Ⅰ号

建立了测定食品中苏丹红Ⅰ号新方法:薄层色谱-紫外可见分光光度法.方法的线性回归方程为:A=0.00583 0.15105ρ,在0.50～10.0 μg/mL之间苏丹红Ⅰ号的浓度与吸光度之间呈线性关系,相关系数R=0.9992,检出限为0.05 μg/mL.测定结果与国家标准HPLC法对照,令人满意.可用于食品中苏丹红Ⅰ号的测定.     

双波长动力学光度法测定邻苯二酚的研究

Fe(Ⅲ)能够催化H2O2氧化中性红和灿烂甲酚蓝混合体系并使其褪色,加入邻苯二酚以后,该催化氧化褪色反应的速度明显提高.分别测定540 nm和640 nm处加入邻苯二酚和没有加入邻苯二酚体系的吸光度变化,发现吸光度的变化之和(△A)与邻苯二酚的浓度之间存在线性关系.研究了反应体系的吸收光谱,优化了实验条件,建立了双波长动力学光度法测定邻苯二酚的新方法.该方法测定邻苯二酚的线性范围为0.16～1.44 mg/L,检出限为0.05 mg/L.方法用于废水样品中邻苯二酚的测定,结果满意.     

薄层色谱-紫外可见分光光度法同时测定食品中的苏丹红Ⅰ～Ⅳ

建立了测定食品中苏丹红色素含量的新方法——薄层色谱-紫外可见分光光度法,对影响测定的因素如样品预处理方式、展开剂等进行了讨论,检测苏丹红Ⅰ~Ⅳ的线性范围分别为0.5~14μg/mL,0.5~10μg/mL,0.5~15μg/mL,0.5~15μg/mL,线性相关系数均为0.999,检出限均为0.05μg/mL。该方法测定结果与国家标准方法测定结果基本一致。     

Chemical Composition and Potential Practical Application of 15 Red Algal Species from the White Sea Coast (the Arctic Ocean)

Though numerous valuable compounds from red algae already experience high demand in medicine, nutrition, and different branches of industry, these organisms are still recognized as an underexploited resource. This study provides a comprehensive characterization of the chemical composition of 15 Arctic red algal species from the perspective of their practical relevance in medicine and the food industry. We show that several virtually unstudied species may be regarded as promising sources of different valuable metabolites and minerals. Thus, several filamentous ceramialean algae (Ceramium virgatum, Polysiphonia stricta, Savoiea arctica) had total protein content of 20–32% of dry weight, which is comparable to or higher than that of already commercially exploited species (Palmaria palmata, Porphyra sp.). Moreover, ceramialean algae contained high amounts of pigments, macronutrients, and ascorbic acid. Euthora cristata (Gigartinales) accumulated free essential amino acids, taurine, pantothenic acid, and floridoside. Thalli of P. palmata and C. virgatum contained the highest amounts of the nonproteinogenic amino acid β-alanine (9.1 and 3.2 μM g⁻¹ DW, respectively). Several red algae tend to accumulate heavy metals; although this may limit their application in the food industry, it makes them promising candidates for phytoremediation or the use as bioindicators.     

动力学荧光增敏法测定痕量钒(Ⅴ)

研究了在稀硫酸介质中柠檬酸存在下,钒(Ⅴ)催化溴酸钾氧化吖啶红的荧光增强作用,建立了催化荧光法测定痕量钒(Ⅴ)的新方法。该方法的线性范围为0.20～3.00μg/L,检出限为0.04μg/L。本法已用于水样、大米和花生仁中痕量钒的测定。     

茜素红与壳聚糖的相互作用机理研究

应用光谱法研究在pH=5.0的反应体系中壳聚糖（CTS）与茜素红（AR）的结合 反应，考察了反应体系中AR/CTS摩尔比、NaCl浓度及CTS的脱乙酰度对茜素红与壳 聚糖相互作用的影响，通过实验测得CTS对AR的最大结合数N_E=4.78×10~3，理论 模型预测最大结合数N_c=4.73×10~3，实验值与理论值一致，并对壳聚糖与茜素红 的相互作用机理提出了合理的解释。     

中性红作试剂荧光光度法测定亚硝酸根

研究了在盐酸介质中ＮＯ＾－２与中性红的亚硝化反应。结果表明，在０．０４８ｍｏｌ／Ｌ的盐酸介质中，ＮＯ＾－２与中性红反应生成无荧光的物质，ＮＯ＾－２在４０－２４０μｇ／Ｌ，范围内与荧光猝灭程度成正比，常见的共存离子不干扰其测定。所拟方法用于水样中ＮＯ＾－２的测定，结果满意。