Study on the Relation between Several Metal Ions and the Growth Metabolism of a Symbiotic Fungus of Sesarma bidens

对一株双齿相手蟹肠道共生真菌Sporothrix sp.(ZJSEF -7),测定了12种金属离子对该菌生长代谢的影响.结果表明,Fe3+、K+、Mn2+、Mg2+、Ca2+和Sb3+可明显促进菌体的生长;Cu2+、Sn2+和pb2+对菌体生长没有明显的影响;Fe2+对菌体生长有强的抑制作用;Al3+和Zn2+完全抑制菌体生长.相手蟹共生菌对部分重金属显示了一定的抗性和强的化学防御功能,深入研究其作用机制,将有助于了解相手蟹共生菌的生物学本质及其生态学作用,对于保护红树林生态环境具有重要的意义.     

九种金属离子对一株南海海洋真菌生长代谢影响的初步研究

研究了9种金属离子对一株南海红树内生真菌B77生长代谢的影响。结果表明,质量浓度为0.15 mg/mL的Zn2+可明显促进该真菌的生长,菌丝体增多,并且使代谢时间缩短,代谢产物产量提高。结果表明,适量的金属离子可以对该真菌的生长,次级代谢产物的生产具有明显的作用。     

优化固氮活性模型信息研究—双齿配体DPPE和DPPM对固氮酶促反应的影响

报道了某些双齿配体对固氮酶促反应影响的研究结果．发现１，２－双（二苯基磷）－乙烷（ＤＰＰＥ）对固氮酶酶促乙炔还原反应有促进作用，但同时又抑制了固氮酶的放氢反应。而比ＤＰＰＥ少一个－ＣＨ２－链的双（二苯基磷）－甲烷（ＤＰＰＭ）却不能表现出对固氮酶促乙炔还原活力的促进作用．对照固氮酶ＭｏＦｅ－蛋白Ｘ－光衍射结构分析结果和量子化学近似计算所导出的固氮酶活性中心结构模型提出了ＤＰＰＥ促进酶促乙炔还原反应的一种可能的解释．     

膦氧双齿配体对Kaminsky型催化剂催化乙烯齐聚的影响

直链低碳α－烯烃是合成线性低密聚乙烯（ＬＬＤＰＥ）和高密聚乙烯（ＨＤＰＥ）的共聚单体,也是生产可生物降解的洗涤剂、高级润滑剂、增塑剂等的重要有机化工原料。目前,国内外对于α－烯烃齐聚均相催化剂的研究主要聚焦在镍和锆络合物上［１～４］。研究表明,改变催...     

一种经MCM-41负载双齿膦钯(0)配合物催化的羰基化Suzuki偶联合成二芳酮的新途径

在催化量的MCM-41负载双齿膦钯(0)配合物存在下,芳基碘化物和芳基硼酸、一氧化碳在常压下能顺利进行羰基化Suzuki偶联反应,高产率地生成了各种二芳酮化合物。MCM-41负载双齿膦钯(0)配合物具有比PdCl2(PPh3)2 更高的活性和选择性,且可回收再用10次其活性基本不变,为各种功能化二芳酮的合成提供了方便实用的新途径。     

乌头类双酯型生物碱对嗜热四膜虫生长代谢的微量热学研究

建立灵敏表征乌头类双酯型生物碱(DDA)对嗜热四膜虫生长代谢影响的评价方法. 采用微量热法, 在不同给药条件下, 以表达功率-时间曲线(热谱曲线)的特征参数生长速率常数(k)、半数抑制浓度(IC₅₀)、最大输出功率(P_max)及达峰时间(t_p)和总产热量(Q_t)为指标, 对嗜热四膜虫生长代谢程度进行客观地量化评价. 结果表明, 随着3种DDA浓度的增加, 达峰时间t_p延长, 生长速率常数k、最大输出功率P_max等随之降低, 且生长速率常数k与相应的浓度间呈现良好的线性关系: r_乌头碱＝0.9910 (IC₅₀＝207.7 μg•mL^－1); r_新乌头碱＝0.9923 (IC₅₀＝412.5 μg•mL^－1); r_次乌头碱＝0.9977 (IC₅₀＝1497 μg•mL^－1). 同时由半抑制浓度IC₅₀得到3种DDA毒性的大小顺序: 乌头碱＞新乌头碱＞次乌头碱. 初步构效关系研究表明, 在化合物C(3)上引入羟基(OH)以及N原子上引入乙基(CH₂CH₃)均可明显增加双酯型生物碱对嗜热四膜虫的毒性作用.     

纳米多孔双金属氧化物在镍钛合金纤维上的原位生长及其对多环芳烃的选择性固相微萃取

采用阳极氧化法在镍钛合金(NiTi)纤维上原位生长了双金属氧化物纳米孔(NiTiONPs)涂层,通过扫描电镜(SEM)和能谱(EDS)考察了电解质组成和电压对形貌的影响。将NiTiONPs涂层的NiTi纤维与高效液相色谱-紫外检测器联用,研究了4种典型芳香分析物的萃取性能。结果表明,富含TiO2的NiTiONPs涂层对多环芳烃(PAHs)具有良好的萃取效率,尤其对苯并[a]芘的萃取选择性优于市售聚二甲基硅氧烷纤维和聚丙烯酸酯纤维。在优化条件下,PAHs的线性范围为0.05~200μg/L,相关系数均大于0.999,检出限为0.012~0.134μg/L。对单支纤维日内和日间分析的相对标准偏差(RSDs)分别为4.0%~5.5%和6.0%~6.8%,使用分批组装的5支纤维分析的RSDs为6.4%~7.6%。实际水样分析的加标回收率为84.5%~111.5%。所制备NiTi纤维至少可重复使用250次以上,重现性好。     

微量热法研究鹿茸4个活性部位对肠道特征菌群生长代谢的影响

建立灵敏表征鹿茸中具有补益活性的4个部位对两种肠道特征菌群生长代谢影响的评价方法.采用微量热法,在不同给药条件作用下,以产热功率-时间曲线(热谱曲线)的特征参数(生长速率常数(k)、最大产热功率(Pmax)、达峰时间(tp)及有效率(E)等)为指标,对肠道主要有益菌(青春双歧杆菌)生长代谢程度进行客观地量化评价.挑选鹿茸促菌最强的活性部位,进一步考察该部位对病原微生物(金黄色葡萄球菌)生长抑制的作用规律.结果表明,鹿茸不同活性部位促进青春双歧杆菌生长代谢强弱顺序为:正丁醇乙醚氯仿乙酸乙酯.活性最强的正丁醇萃取液对病原微生物(金黄色葡萄球菌)抑制影响的研究表明,正丁醇萃取液在浓度大于200μg·mL-1时,对金葡菌生长具有抑制作用.且tp随药液浓度的增加而相应地延长;k,Pmax均随浓度的增加而相应地减小.微量热法具有灵敏准确、实时在线、重现性好等特点,可用于名贵药材——鹿茸的活性部位的筛选,也为药效物质的研究提供了一个新的研究思路和方法.     

微量热法研究环境NaCl浓度对盐生盐杆菌生长代谢的影响

采用TAM air微量热系统和安瓿法测定了盐生盐杆菌在不同NaCl浓度中生长的生长产热曲线, 拟合得到盐生盐杆菌在不同NaCl浓度中生长的热动力学方程和热动力学参数, 并分析了盐生盐杆菌生长的各种热动力学参数与环境NaCl浓度的关系. 由此发现, 盐生盐杆菌生长的最适NaCl浓度并不是传统认为的一个宽泛的范围——3.5 mol·L^-1至约5.2 mol·L^-1 (NaCl饱和), 而是约3.9 mol·L^-1. 在环境NaCl浓度由3.9 mol·L^-1逐步升高至饱和的过程中, 盐生盐杆菌的生长代谢持续减弱. 进一步的透射电镜观察发现在近饱和的NaCl浓度中生长的盐生盐杆菌细胞发生了质壁分离, 较好地解释了微量热研究的结果. 由此对NaCl浓度变化导致嗜盐古生菌表面结构改变提出了新的解释.     

温控相转移配体及催化(V)——单,双-对聚氧乙烯基三苯基膦的合成及其催化性能研究

近年来,水/有机两相催化已成为均相催化多相化研究的主流[1].其中,新型水溶性瞵配体的合成和两相催化新体系的设计尤为引人关注[2].最近我们发现[3],聚醚型水溶性膦-铑催化剂在高温下可溶入有机相对反应进行催化,而在冷却后又重返水相和产物分离.     

Study on the Influence of Metal Ions on the Dispersion of Fine Calcium Gangue Minerals

In this study, the calcium gangue material calcite (−10 μm) was used to investigate the effects of different kinds of metal ions and dosages on the dispersion behavior of calcite. The test results showed that the dispersion behavior of calcite was poor under strongly alkaline conditions without the addition of metal ions, and the reason for that was calcite dissolved ions. The degree of influence of different metal ions on calcite dispersion behavior was Fe³⁺ > Mg²⁺ > Na⁺. The three metal ion dosage tests showed that the dispersion behavior of calcite became poorer with the increase of metal ion dosage. This mainly showed that with the increase of Na⁺ dosage, the trend of the dispersion behavior of calcite was not obvious, but with the increase of Fe³⁺ and Mg²⁺ dosage, the trend of calcite dispersion behavior changed more. The dispersion behavior of calcite was devastated by 5 × 10⁻⁴ mol/L Fe³⁺ at pH = 4–12. The different mechanisms of the three metal ions were identified by zeta potential, solution chemistry, and XPS analysis. Na⁺ only changed the zeta potential value of the calcite surface, which acted as a compressed electric double layer. However, the formation of metal hydroxide species or metal hydroxide surface precipitation due to the adsorption of Fe³⁺ and Mg²⁺ on the mineral surface resulted in the change of the dispersion behavior of calcite.     

聚苯胺及其复合物对重金属离子的高效吸附性能

基于国外最新文献,系统总结了近年来聚苯胺及其复合物的制备方法及其重金属离子吸附性能,重点分析了吸附性能特征,指出聚苯胺及其复合物具有吸附下限浓度低、达到吸附平衡快以及解吸附性能优异等特点.填充有聚苯胺颗粒的吸附柱在动态处理初始浓度为83 ng/L的汞离子溶液时,经一次吸附与解吸循环操作后,汞离子的富集倍数可达120倍.应用于冷原子吸收光谱的待测样品的浓缩与富集,可以将汞的测试下限拓展到0.05 ng/L.聚苯胺及其复合物在痕量重金属离子的高效富集与灵敏探测等方面展示了广阔的应用前景.     

The Study of Influence of Metal Ions on Thermal Decomposition of Humic Acids

Investigations of the influence of the following metal ions: Ca, Mg, Ba, Cr, Mn,Co, Ni, Fe(II), Fe(III), Cu, Zn, Cd, Pb, Hg, Al and Ag on thermal decomposition of humic acids were carried out. Metal-humic compounds were obtained by ion exchange method and by complexing of metal cations on humic acids. For the investigations of thermal decomposition TG and DTA were used. Presence of metal ions in structure of humic acids mostly increases intensity of their thermal decomposition particularly the Hg and Cu ions.They shift this process to lower temperatures 100–300°C. Mass loss of organic matter in this temperature range in humic-mercury compounds are higher by more than 35%, and in humic-copper compounds are higher by more than 20% compared with the mass loss of humic acids itself. Ni and Co ions also increase the intensity of thermal decomposition of humic acids, but Ca, Ba and Mg ions inhibit that process. This revised version was published online in July 2006 with corrections to the Cover Date.     

Exploring the Interaction between Graphene Derivatives and Metal Ions as a Key Step towards Graphene–Inorganic Nanohybrids

The assembly of graphene derivatives and inorganic nanostructures opens up an exciting new field in the functionalization of nanomaterials. However, a better understanding of the interaction between graphene derivatives and inorganic precursors remains a challenge. This work provides an efficient strategy for exploring this interaction by first modifying graphene oxide with aniline, glycine, and glycyl glycine, respectively, and thus engineering the chemical microenvironments on graphene sheets for anchoring metal ions. After that, the affinities of graphene derivatives to various metal ions can be investigated with the help of a conventional electrochemical method. The method highlights the importance of graphene chemistry in hybrid preparation and provides design principles for chemical modifiers used in the construction of multifunctional carbon–inorganic nanostructures.     

改性壳聚糖的制备及其对金属离子的吸附性能

用对羟基苯甲醛、水杨醛和香草醛对壳聚糖进行了修饰.探讨了产物对微量Hg2+,Pb2+,Au3+,Cu2+,Ag+,Cr3+,Cd2+,Ni2+和Zn2+的吸附性能.结果表明,改性后的壳聚糖具有不易流失、易再生的特点,并且对离子的去除率较高,尤其对Hg2+,Pb2+和Au3+,去除率更高.     

青藏高原雪冰样品中低含量水溶金属离子分析方法对比研究

从采自青藏高原阿汝和古里雅冰川的两支冰芯中选取31个样品,分别用三种仪器对比分析K^+、Na^+、Ca^2+、Mg^2+四种水溶金属离子,寻求最佳分析方案。分析结果对比发现,电感耦合等离子体发射光谱(ICP-OES)法在K+测量中存在困难,而离子色谱(IC)法和电感耦合等离子体质谱(ICP-MS)法均能够满足要求,且分析结果具有高度的一致性,四种离子的相关系数(R2)均在0.97以上,且并未出现ICP-MS法比IC法测量值明显偏高的现象。因此,除IC法外,ICP-MS法也是检测青藏高原雪冰样品中水溶金属离子的有效手段,其测定速度更快,且可以同时进行微、痕量元素检测,适用于大批量冰芯样品的快速分析。     

2DFT Research of the Interaction between Metal Ions and CO2 along with H2O

The interaction between several different metal ions and H2O along with CO2 has been researched theoretically in the CO2 photocatalytic reduction with H2O system at the B3LYP level by DFT.The computational results revealed that relatively high valence metal ions loaded on TiO2 activated the H2O and CO2 consumingly,and it might be looked as some proofs for modified photocatalyst selecting.In addition,the metal ions conducted photoelectrons to prevent the re-combination of photoelectrons and holes during the reaction process.     

二价金属离子对磷脂聚集体的影响

通过浊度分析和激光光散射光谱研究了二价金属离子（Ca2＋、Cu2＋和Mn2＋）对蛋黄卵磷脂(EYPC)聚集态的影响.结果表明，自由的二价金属离子对EYPC囊泡有破坏作用,并使EYPC囊泡发生相转变,形成胶束;而与牛磺胆酸钠(TC)结合的二价金属离子使EYPC囊泡半径减小,但不破坏EYPC囊泡.