基于模糊聚类算法的气溶胶单粒子飞行时间质谱在线数据分析系统

介绍了一个在气溶胶分析中大量单粒子质谱数据的处理方案.实现了对气溶胶飞行时间质谱仪采集的单极性激光解吸附电离质谱的在线实时评估.在自动完成最近一次单粒子质谱采集和质谱峰分析之后,质谱信息的统计和评估通过一个模糊聚类法则(Fuzzy C-means,FCM)结合事先的手工分类或是粒子分类数据库实现了对单粒子的分类的立即归属,同时就粒子种类、粒径分布和时间进程的化学成分的变化进行更深入的研究.运用该系统成功地对邻苯二甲酸二正辛酯(Dioctylphthalate,DOP),氯化钙(CaCl2)产生的气溶胶单粒子进行了在线分析,得到了大量单粒子质谱和粒径的信息数据.     

3-羟基-7-氧代-5,6-二氢吡唑[3,4-e]并-1,2,4-三嗪的合成

以3-氨基-5-吡唑啉酮为原料,合成了3-羟基-7-氧代-5,6-二氢吡唑[3,4-e]并-1,2,4-三嗪,并对目标物及文献中未见报道的中间体如3-氨基-5-氧代-4-吡唑啉酮腙衍生物等,通过元素分析I、R1、HNMR和质谱分析确定了其结构。     

7-甲基-3-羟基吡唑[4,3-e]并-1,3,4-噁二嗪的合成

以3-甲基-5-吡唑啉酮为原料,合成了标题化合物,并对目标物及文献中未见报道的中间体如3-甲基-5-氧代-4-吡唑啉酮腙衍生物等,通过元素分析I、R1、HNMR和质谱分析确定了其结构。     

电解质溶液热力学性质的研究进展

从电解质溶液的经典理论、半经验模型和统计力学3方面综述了电解质溶液热力学性质的研究进展,并对各种理论和模型在理论与实践方面的局限性作了相关评述。从分子、离子角度对电解质溶液的热力学性质进行研究比较,探讨了其宏观热力学性质与微观结构的相关性。展望了电解质溶液热力学理论近期研究的热点和未来的发展方向。     

复配技术在聚烯烃材料抗静电改性中的应用

对常用抗静电改性助剂及其机理、复配抗静电技术作了简要的介绍,并对国内外复配抗静电技术在聚烯烃材料抗静电改性中的应用作了简要的总结。     

聚合物／蒙脱土纳米复合材料的研究进展

综述了蒙脱土(MMT)的结构特征、蒙脱土的有机化改性、聚合物/蒙脱土纳米复合材料(PMN)的制备方法以及聚合物/蒙脱土纳米复合材料的结构特性及性能特点。     

基于小波变换的地震数据混合编码压缩算法研究

随着地震勘探研究的不断深入,地震资料的处理和解释量也越来越庞大,其中数据的冗余量也比较大。对这些数据进行合理的压缩处理已经成为一个重要的课题,本篇文章根据多分辨分析思想,用小波变换对地震数据进行多级分解得到多个子带,然后对每个子带做不同策略的量化和编码处理,仿真结果表明,这种压缩编码算法,既能得到期望的压缩比,而且压缩后的地震数据所带来的误差比单一的编码压缩算法要小很多。     

微生物发酵生产2,3-丁二酮的研究

2,3-丁二酮又称双乙酰,是一种黄色至浅绿色具有强烈奶油香味的重要香料。2,3-丁二酮传统上用合成法生产,我们以农副产品为主要原料,利用选育的高产菌株发酵生产,发酵工艺条件温和,产品风味自然、逼真、安全性高,视同天然产品,符合人们崇尚自然的趋势,可广泛用于食品、日化、饲料香精的生产。     

Effect of structural and electrochemical properties of different Cr-doped contents of Li[Ni1/3Mn1/3Co1/3]O2

Layered Li[Ni_(1−x)/3Mn_(1−x)/3Co_(1−x)/3Cr_x]O₂ materials with x = 0, 0.01, 0.02, 0.03, 0.05 are prepared by a solid-state pyrolysis method. The oxide compounds were calcined with various Cr-doped contents, which result in greater difference in morphological (shape, particle size and specific surface area) and the electrochemical (first charge profile, reversible capacity and rate capability) differences. The Li[Ni_(1−x)/3Mn_(1−x)/3Co_(1−x)/3Cr_x]O₂ powders were characterized by means of X-ray diffraction (XRD), charge/discharge cycling, cyclic voltammetry, and SEM. XRD experiment revealed that the Li[Ni_(1−x)/3Mn_(1−x)/3Co_(1−x)/3Cr_x]O₂ (x = 0, 0.01, 0.02, 0.03, 0.05) were crystallized to well layered -NaFeO₂ structure. The first specific discharge capacity and coulombic efficiency of the electrode of Cr-doped materials were higher than that of pristine material. When x = 0.02, the sample showed the highest first discharge capacity of 241.9 mAh g⁻¹ at a current density of 30 mA g⁻¹ in the voltage range 2.3–4.6 V, and the Cr-doped samples exhibited higher discharge capacity and better cycleability under medium and high current densities at room temperature.     

Synthesis and structure of the n = 4 member of the framework aluminium alkylenediphosphonate series Al2[O3PCnH2nPO3](H2O)2F2

We report here the solvothermal synthesis and crystal structure of the hybrid inorganic-organic framework material Al₂[O₃PC₄H₈PO₃](H₂O)₂F₂⋅2H₂O (monoclinic, 1P2₁/m, a = 4.961(2) ?, b = 11.930(5) ?, c = 10.727(5) ?, β = 93.972(6)^∘, Z = 2, R(F, F² > 2σ) = 0.094, R_w(F², all data) = 0.262), the third member of the Al₂[O₃PC_nH_2nPO₃](H₂O)₂F₂ framework series. The structure is formed from corrugated chains of corner-sharing AlO₄F₂ octahedra in which alternating AlO₄F₂ octahedra contain two fluorine atoms in a trans or a cis configuration. The diphosphonate groups link the chains together through Al-O-P-O-Al bridges and through the butyl groups to form a three-dimensional framework structure containing a one-dimensional channel system consisting of one type of channel only. The channels contain four extra-framework water molecules per unit cell. The formation of this member of the series shows that the form of the alkyl chain can successfully define the number of channel types and the channel length in this hybrid framework system.