207Pb/206Pb determination of zircons by laser probe-inductively coupled plasma mass spectrometry

Laser probe_inductively coupled plasma mass spectrometry (LP_ICP_MS) was used to determine 207 Pb/ 206 Pb ratios in single zircon grains. A Nd∶YAG laser operating at 1 064 nm and a Fisons_VG PQII Turbo ICP_MS were employed. For the known zircons, the 207 Pb/ 206 Pb results of LP_ICP_MS are close to the thermal ionization mass spectrometry (TIMS) results. The spatial resolution of this method is 40-50 μm and the sensitivities for lead isotopes are about 300-400 cps/ppm. The precision of 207 Pb/ 206 Pb ratio is 0.3%-4% and depends on the lead concentration of the sampling pits. LP_ICP_MS provides a simple, rapid and economic method for zircon 207 Pb/ 206 Pb determination.     

SAR images classification method based on Dempster-Shafer theory and kernel estimate

To study the scene classification in the Synthetic Aperture Radar (SAR) image, a novel method based on kernel estimate, with the Markov context and Dempster-Shafer evidence theory is proposed. Initially, a nonparametric Probability Density Function (PDF) estimate method is introduced, to describe the scene of SAR images. And then under the Markov context, both the determinate PDF and the kernel estimate method are adopted respectively, to form a primary classification. Next, the primary classification results are fused using the evidence theory in an unsupervised way to get the scene classification. Finally, a regularization step is used, in which an iterated maximum selecting approach is introduced to control the fragments and modify the errors of the classification. Use of the kernel estimate and evidence theory can describe the complicated scenes with little prior knowledge and eliminate the ambiguities of the primary classification results. Experimental results on real SAR images illustrate a rather impressive performance.     

论CEO的激励与监督机制

主要研究ＣＥＯ的行为动机，在此基础上，阐述了激励和监督机制对完善现代法人治理结构的重要意义。     

磁化水抑垢中SO_4~(2-)浓度限值实验与探讨

应用动态实验，探讨了ＳＯ２－４浓度对磁化水抑垢效果的影响．确定抑垢时ＳＯ２－４浓度限值为ＣＨＣＯ－３／ＣＳＯ２－４大于２．２     

3—苯基偶氮—5—磺基水杨酸与钕（Ⅲ）,铜（Ⅱ）络合物的合成与表征

在ｐＨ＝３．８酸性条件下合成了３－苯基偶氮－５－磺基水杨酸与Ｎｄ（Ⅲ）的酸式络合物，在弱碱性条件下合成了该染料与Ｎｄ（Ⅲ）的羟式络合物及Ｃｕ（Ⅱ）的络合物，对这些络合物进行了元素分析、热重分析，并测定了电导和红外光谱，确定了分子式，讨论了可能的配位环境。Ｎｄ（Ⅲ）的络合物中奶均以二齿形式配位，偶氮基皆未参与配位，羧式络合物中酚基则参与配位。在Ｃｕ（Ⅱ）的络合物，羧酸根以二齿形式配位，酚基，偶氮基也     

具有非光滑边界的强拟凸多面体上的Koppelman-Leray-Norguet公式

得到了Ｃ＾ｎ空间中具有非光滑边界的强拟凸多面体上微分形式的Ｋｏｐｐｅｌｍａｎ－Ｌｅｒａｔｙ－Ｎｏｒｇｕｅｔ公式及其δ－方程的连续解，其特点是不含有边界积分，从而避免了边界积分的复杂估计。     

电感耦合等离子体质谱法测定高纯气体中痕量铝、磷、硼

研究了用电感耦合等离子体质谱（ICP—MS）测定高纯气体五氟乙烷中铝、磷、硼等杂质的分析方法．在最佳仪器条件下，通过选择合适的吸收液与测定同位素、采用Sc作为内标以及碰撞池技术，避免了基体效应以及多原子离子对测定的干扰．方法简单、灵敏度高，对高纯气体的质量监控有指导意义．     

Immobilization of 12-phosphotungstic heteropolyacid on amine-functionalized SiO<Subscript>2</Subscript> for tetrahydrofuran polymerization

The 12-phosphotungstic heteropolyacid (HPW) was immobilized on the surface of a silica carrier modified by the amine groups of organosilane γ-aminopropyl triethoxysilane (APTES), and its catalytic performance was investigated for tetrahydrofuran (THF) ring-opening polymerization. This amine-functionalized catalyst exhibited better activity, and the polytetramethylene ether glycol (PTMG) yield was 63.7%. The 12-phosphotungstic heteropolyacid supported on aminopropyl-functionalized SiO₂ support (HPW/SiO₂-APTES) was reused four times and showed a good maintenance of activity which was better than that of the conven-tional catalyst HPW supported on SiO₂ (HPW/SiO₂). These results were obtained using infrared spectroscopy, nuclear magnetic resonance spectroscopy, nitrogen adsorption and X-ray diffraction. HPW on the HPW/SiO₂-APTES catalyst exhibited higher dispersed state and maintained a more stable structure than that of the HPW/SiO₂ sample.     

泰山山地水系网特征研究

运用Horton定律以及分形分维理论与方法,对泰山(本部区)地区水系、流域的特征进行较为详细的分析研究,揭示了泰山水系的分布格局、结构特征,区内水系发育的差异性;分析影响研究区水系网特征形成的因素,并探讨其发育的状态.     

Different Performances of H2O2 to Oxidise Aldicarb and Hexazinone in the Advanced Oxidation Process of Ozone/Hydrogen Peroxide

The degradations of hexazinone and aldicarb by direct ozonation combined an advanced oxidation process（ AOP） of O3/H2O2 were investigated in this study focusing on the oxidation mechanism by identifying the hydrogen peroxide consumption during the oxidation process of the two chemicals. The results showed that H2O2 could enhance the removal rate of the triazine herbicide hexazinone,and it was consumed along with the variation of removal rate in the light of different pH levels. The addition of H2O2 contributed little to the removal of the thiocarbamate herbicide aldicarb and H2O2 content kept constantly throughout the degradation process. Tert-butyl alcohol（ TBA） effectively scavenged the ·OH radical for hexazinone,but had no effect on the removal rate of aldicarb. Aldicarb removal was mainly attributed to direct ozonation molecule in both O3（ 97.00%） and O3/H2O2（ 96.76%）systems. Moreover,sole O3 could hardly oxidize hexazinone whereas·OH radicals contribute respective 74.70% and 97.50% of removal in O3 system and O3/H2O2 AOP. All of these findings suggest that the mechanism of ·OH radical generation and the chain reaction in O3/H2O2 AOP should be further discussed.