离子液体中用Heck反应合成2-取代萘烯丙醇化合物

利用Heck反应, 在离子液体、金属钯或镍、碱和膦配体反应体系中, 由卤代萘与烯丙醇反应, 制得了高收率和高选择性的2-取代萘烯丙醇化合物. 该方法原料便宜易得、操作简单、反应体系可循环使用. 并讨论了醋酸镍替代醋酸钯、不同膦配体、溶剂及碱对反应转化率的影响. 通过核磁共振、红外光谱、质谱和元素分析对产物的结构进行了表征.     

白菜DNA甲基化水平的反相离子对高效液相色谱法研究

建立了反相离子对液相色谱测定白菜的DNA甲基化水平的方法。采用的色谱柱为HypersilBDSC18柱(200mm×4.0mm,5μm),以pH4.0的甲醇-5mmol·L-1庚烷磺酸钠-三乙胺(10:90:0.2,体积比)的混合液为流动相,UV检测器波长为273nm。通过测定DNA水样所产生的胞嘧啶和甲基胞嘧啶的含量,即可得知DNA甲基化程度。胞嘧啶和甲基胞嘧啶回收率分别为99.6%及103.3%,RSD为3.7%(日内)及5.2%(日间)。     

[Ni(dien)_2]_2[Mn(NCS)_6]·H_2O的合成、晶体结构

硫氰酸根的结构为N≡C－S－，其两端的N原子和S原子分别有一对和三对孤对电子，因此，硫氰酸根可采用多种不同的配位模式与金属离子发生配位。硫氰酸根可作为单齿配体与一个金属离子配位，形成M－SCN或M－NCS的单核配合物，也可以作为桥联配体同时与两个、三个甚至四个金属离子配位形成多核配合物犤１～３犦；另一方面，硫氰酸根是一个具有一定共轭性的偶极子，可传递磁相作用。因此，选择硫氰酸根作为桥联配体，将多个顺磁金属离子桥联形成一维、二维或三维结构的多核金属配合物分子，并研究它们的磁性已成为分子磁学的一个研究领域…     

Chemiluminescence Determination of Benzoic Acid Using A Solid-Phase Verdigris Reactor

Benzoicacidisacommonadditiveusedwidelyasfoodpreservativeandplasticizer.Itcouldpromoteseverereactiontoallergicpopulationevenatlowconcentrationlevel1.Routinemethodsfortheassayofbenzoicacidincludeschromatographic2-6,spectrophotometry7,8,capillaryelectrophoresis9-13andelectrochemicaltitration14.Stokes15etal.monitoredairbornebenzoicacidbasedonsurface-enhancedRamanscatteringtechniques.Thereisalsoreportonamicrobialsensorusingpseudomonasforbenzoicacidandtheirderivativesinaqua16.Interestofusinglumines…     

A New Asterosaponin from the Starfish Culcita novaeguineae

A new asterosaponin named novaeguinoside A, along with a known saponin, asteronyl pentaglycoside sulfate, was isolated from the starfish Culcita novaeguineae. The new compound was identitied to be sodium 6α-O-{β-D-fucopyranosyl-(1→2)-β-D-fucopyranosyl-(1→4)-[β-D-quinovopyranosyl-(1→2)]-β-D-xylopyranosyl-(1→3)-[β-D-quinovopyranosyl}-5α-pregn-9(11)-en-20-one-3β-yl-sulfate by extensive spectral analysis and chemical evidence.     

Thermodynamic and Equilibrium Composition Analysis of Using Iron Oxide as an Oxygen Carrier in Nonflame Combustion Technology

1. Introduction The utilization of fossil fuels causes serious neg- ative impacts on the environment and human life. There are many pollutants such as SOx, NOx and CO2 emission produced from the combustion of coal, oil and natural gas. It has been known for more than 100 years that CO2 is a greenhouse gas and that the release of CO2 from fossil fuel combustion may affect the climate of the earth. In the last years the concern over the aspects of an increased release of greenhouse gases has…     

Application of symplectic algorithms to QCT calculation:H+H_2 system

The basic theory of symplectic algorithm was introduced. A comparison between Runge-Kutta method and symplectic integration method was preformed in the simulation of the long time behavior of H + H2 system on BKMP potential energy surface. Our results reveal a dis-sipative behavior in the integral of ordinary differential equation by the fourth order Runge-Kutta method, which causes incorrect simulation results in QCT calculations. However, when the symplectic integration method is applied, the dissipative behavior is not found in the same system. When the initial state is the same, the energy deviation of fourth order symplectic integral method is almost one percent of that of fourth order Runge-Kutta method in a 60000-step simulation, and that of sixth order symplectic integral method is much less. These results show that the symplectic integral methods are always the better choice in the integral calculation of the long time behavior in maintaining energy conservation.     

盐生盐杆菌生长过程热动力学研究

用 LKB2 2 77生物活性检测系统测定了盐生盐杆菌 R1、J7、S9以及 R1和 J7的融合子 F9生长的产热功率曲线 .根据曲线的特征 ,建立了古生菌生长过程的热动力学方程 :ln[P· ( 1 -P/Pm) r- 1 ]=ln[P0 · ( 1 -P0 /Pm) r- 1 ]+k· t.由此求得了盐生盐杆菌的生长速率常数 ,并对此模型和融合子 F9的生长进行了讨论 .该热动力学方程描述了一系列非理想的细菌生长过程的产热功率曲线 ,并将其与经典的指数式生长模型和 lo-gistic模型进行了比较 ,它具有更广泛的适用性 .首次报道了微量热技术在古生菌中的应用     

Fe(III)与2,3-二羟基苯磺酸钠配位反应的动力学研究

[H+]在0.01～0.70mol?L-1范围内,离子强度为1.00mol?L-1,[Fe(III)]>>[配体]、[H+]>>[配体]的条件下,研究了Fe(III)与2,3-二羟基苯磺酸钠(Tiron)的配位反应.发现当[H+]≤3.00×10-2mol?L-1时,[Fe(III)]2对反应速率有明显的贡献.求得了相关反应的动力学参数,从而揭示了FeOH2+和FeOH24+与Tiron配位的解离反应途径及FeOH32+的缔合反应机制,并提出了该配位反应的可能机理.     

N－亚硝基化合物的结构／致癌活性的三维构效关系研究

用比较力场分析研究了Ｎ－亚硝基化合物的结构与致癌活性的关系，考察了网络结构和探针原子对结果的影响．结果表明，立体效应和静电作用场是描述其致癌活性和进行结构性能关系研究的最重要的结构参数。