α-单取代环十二酮肟及缩氨基硫脲的合成及晶体结构

单晶X射线衍射分析表明, α-单取代环十二酮与氨衍生物羟胺和氨基硫脲发生缩合反应得到两种母体构象均为[3333], 而取代基为边外向或角反向的α-单取代环十二酮肟或缩氨基硫脲. 利用底物的“角位羰基参与反应”原理, “记忆效应”及进攻试剂与底物是否形成氢键解释了这一实验结果. 通常情况下, 试剂从空间障碍小的一面进攻羰基而生成α-角反取代环十二酮肟或缩氨基硫脲. 当试剂与底物的取代基之间能够形成分子间氢键时, 则生成α-边外取代环十二酮肟或缩氨基硫脲.     

气色相谱-质谱法测定化妆品中的氯霉素

氯霉素是一种广谱抗生素,化妆品卫生规范规定氯霉素等抗生素为禁用物质.关于氯霉素的检测多采用高效液相色谱(HPLC)[1]和高效液相色谱-质谱(HPLC-MS)[2] 测定,或者经N,O-双三甲基硅烷基-三氟乙酰胺(BSTFA)、三甲基氯硅烷(TMCS)等硅烷化[3-4]后进行气相色谱(GC)、GC-MS测定.本文建立了采用较为普通的乙酸酐试剂进行衍生化,然后用GC-MS测定的方法.将该法应用于化妆品中氯霉素的检测,取得了较好的效果.     

轻质直链烯烃异构化催化剂研究进展

上世纪80年代起,全球汽油质量开始向无铅、低芳烃、低蒸汽压、高辛烷值和高氧含量的方向发展,这也很大程度上推动了甲基叔丁基醚(MTBE)和甲基叔戊基醚(TAME)的迅速发展,而作为其原料的C4和C5异构烯烃的来源也显得尤为重要.因此,关于C4、C5轻质直链烯烃骨架异构化技术的研究骤然升温,从而掀起了一股轻质直链烯烃骨架异构化技术的研究热潮.另一方面,汽油中C5~C8的直链烯烃通过骨架异构化反应能够有效地提高汽油辛烷值,以适应新的燃料规范的要求,这也在一定程度上推动了轻质烯烃骨架异构化技术的发展.1直链烯烃骨架异构化的机理研究由于…     

Effect of Ce<Superscript>3+</Superscript> on spectral characteristic of D1/D2/Cytb559 complex from spinach

It was studied by spectroscopy that PSII reaction center complex consisting of three polypeptides, D₁, D₂ and Cytb559, were purified from PSII particle of CeCl₃ treated spinach. The results of the experiment show that Ce³⁺ could improve the growth of spinach, and accelerate electron transport of PSII particles. Of chl-a of UV-Vis spectrum of D1/D2/Cytb559 complex, Soret band was blue-shifted by 3 nm and Q band by 2 nm, respectively, and the fluorescence emission peak was blue-shifted by 5 nm in CeCl₃-treated spinach compared with the one in control. By the extended X-ray absorption fine structure (EXAFS) spectroscopy methods, it has been found that Ce³⁺ is coordinated with 8 nitrogen atoms in the first coordination shell with Ce-N bond length of 0.253 nm, and Ce³⁺ with 6 oxygen atoms in the second coordination shell with Ce-O bond length of 0.32 nm. However, the secondary structure of D1/D2/Cytb559 complex by circular dichroism (CD) spectroscopy has no significant change after CeCl₃ treated. It might be that Ce³⁺ binds to porphyrin rings of chlorophyll and oxygen of amino acid residue of polypeptide in D1/D2/Cytb559 complex, and then accelerates the primary reaction of PSII, intensifies function of P680⁺ primary electron donor of D1/D2/Cytb559, but there is little change in conformation of PSII reaction center complex.     

基于新型核与灰度序列的时滞GM(1,N)模型及其应用

为了解决GM(1,N)模型在新型核与灰度的基础上,对驱动项的延迟作用机理不明确的问题,将时滞参数引入到GM(1,N)模型的驱动项中,构建了基于新型核与灰度的时滞GM(1,N)模型,分析了时滞参数的辨识方法,讨论了新模型的建模机理。为了更好地对该模型的有效性进行验证,将优化的时滞GM(1,N)模型对南京市的雾霾进行预测分析,选择GM(1,N)模型、一元回归模型与文中的优化模型进行对比。结果显示,优化模型对PM₁₀浓度的拟合精度更高,且误差均控制在5%之内,从而验证了提出的优化模型适用于具有时滞特征数据的模拟和预测。     

STUDY ON THE DUCTILE DEFORMATION DOMAIN OF THE SIMPLE SHEAR IN ROCKS——TAKING BRITTLE FAULTS OF THE COVERING STRATA IN THE SOUTHERN JIANGSU AREA AS AN EXAMPLE

A study on the ductile deformation domain of the brittle fault in the shallow level ofthe crust is a new probe field for the modern structural geology. Taking the southern Jiang-su Province area as an example the orientation measurement of quartz crystals, the com-positional texture observation of three pressure sensitive minerals and the rheological param-eter determination of dislocation densities, etc. have been demonstrated and analysed basedon typical samples in the present paper. In addition, their generation mechanisms arealso discussed from the cataclastic rheology, the dynamic differentiation and the simpleshearing, specially, from the Ode strength theory. Finally, a generative relationship betweenthe ductile deformation domain of the brittle fault system, in the regional layer--slip andthe formation of the stratabound ore deposit is shown as well.     

γ—Mo2N合成过程中的热变化及中间产物的研究

采用ＤＴＡ技术，通过改变升温速率研究了γ－Ｍｏ２Ｎ合成过程中的热变化，并经ＸＲＤ，ＢＥＴ及ＩＲ测试，对ＤＴＡ曲线中的谱峰进行归属，考察了中间产物，ＤＴＡ结果表明，在ＭｏＯ３和ＮＨ３程序升温反应过程中有放热峰及吸热峰出现，且随升温速率的长高，放热峰面积与吸热峰面积之比逐渐减小，结合ＸＲＤ及ＩＲ结果可知，ＤＴＡ曲线听放热峰可归属为由ＭｏＯ３变化为ＭｏＯ２的还原峰，吸热峰则归属为由ＭｏＯ２变化为Ｍｏ２Ｎ     

A New Method to Investigate the Clustering Phenomena in Supercritical Fluids

EstimationoflocaldensityofsolventaboutthesoluteSolvatochromicbehaviorsofspectroscopicprobesarewidelyusedtoestimatethesol-ventstrengthofsupercriticalfluids(SCF,).i-3lnthiswork,thesolvatochrondcshiftofthen-n*transitionbandforacetone(O.o37mo1.L-')insupercrihcal(SC)CO2wasde-terminedbyUVspectroscopytostUdythesolvationeffect.TheMcRae-BaylissexpressionbasedonthedielectriccontinUUInmodelgivestherelahonshipbetWeenso1vatochromicshiftandpo1arizabilityofnonPolarsolvents4-5asfollows:wherevisthewave…     

导数阴极溶出方波伏安法测定卡那霉素注射液含量

研究了汞 卡那霉素络合物的电化学行为 ,并建立了导数阴极溶出方波伏安法测定卡那霉素注射液含量的方法。在 pH 4 .7的HOAc NaOAc缓冲溶液中 ,在约 0 .12 6V (vs.SCE)处出现一个汞 卡那霉素络合物的还原峰 ,卡那霉素的浓度在 0 .0 2～ 1.5mg·ml- 1之间与导数方波伏安图的峰高存在良好的线性关系 ,回归方程ip(10 - 4A) =3.6C(mg·ml- 1) + 0 .4 6 ,相关系数为 0 .992 0。方法简便、灵敏、准确 ,可用于卡那霉素注射液含量测定     

氨-碘酸盐介质中白喉类毒素的平行催化氢波

在 0 .4mol/LNH3 NH4Cl (pH 8.3 1 )介质中 ,白喉类毒素 (DT)于 - 1 .89V(vs.SCE)处产生的极谱催化氢波可被碘酸钾进一步催化 ,峰电流明显增大 ,但峰电位不变 ,产生一种氢的新动力波 ,建议称其为平行催化氢波。在 0 .4mol/LNH3 NH4Cl(pH 8.3 1 ) - 5 .0× 1 0 - 3 mol/LKIO3介质中 ,DT平行催化氢波的二阶导数峰电流与其浓度在 0 .2 μg/mL～ 1 .0 μg/mL内呈线性关系 ,可用于生物制品中DT含量的测定。