垃圾焚烧中氯化物对重金属Pb迁移转化特性的影响

采用管式炉和模拟垃圾对垃圾中氯化物对重金属Pb迁移转化特性的影响进行了研究,使用ICP-AES(美国EPA消解方法)、SEM、EDS和XRD等对重金属浓度、灰渣表面形貌、成分和灰渣X射线衍射物相等进行了分析。结果表明,氯化物含量的增加使得Pb生成更多易挥发性物质,从而向飞灰迁移分布,但有机氯PVC的影响比无机氯NaCl的大。无机氯NaCl和有机氯PVC对焚烧中Pb迁移转化作用机理不同,NaCl易与Pb反应生成PbCl2,而PVC与Pb反应除了生成PbCl2外,还生成了Pb(ClO4)2、PbCl2O4和PbO2。同时焚烧温度和停留时间也是焚烧中Pb迁移分布的两个主要影响因素。     

ETHYLENE/1-HEXENE COPOLYMERIZATION BY SALICYLALDIMINATO VANADIUM(Ⅲ) COMPLEXES ACTIVATED WITH DIETHYLALUMINUM CHLORIDE

Mono salicylaldiminato vanadium(Ⅲ) complexes(1a-1f)[RN = CH(ArO)]VCl_2(THF)_2(Ar = C_6H_4(1a-1e),R = Ph,1a;R = p-CF_3Ph,1b;R = 2,6-Me_2Ph,1c;R = 2,6-iPr_2Ph,1d;R = cyclohexyl,1e;Ar = C_6H_2tBu_2(2,4),R = 2,6-iPr_2Ph, 1f) and bis(salicylaldiminato) vanadium(Ⅲ) complexes(2a-2f)[RN = CH(ArO)]_2VCl(THF)_x(Ar = C_6H_4(2a-2e),x = 1 (2a-2e),R = Ph,2a;R =p-CF_3Ph,2b;R = 2,6-Me_2Ph,2c;R = 2,6-iPr_2Ph,2d;R = cyclohexyl,2e;Ar = C_6H_2tBu_2(2,4),R = 2,6-iPr_2Ph,x = 0,2f) have been evaluated as the active catalysts f...     

含N,N-二(2-苯并咪唑甲基)亚胺单核镍(Ⅱ)配合物与DNA相互作用的研究

用荧光光谱法和紫外-可见吸收光谱法研究了含N,N-二(2-苯并咪唑甲基)亚胺单核镍(Ⅱ)配合物与小牛胸腺DNA(ct-DNA)作用的机理。结果表明,随着ct-DNA浓度的增加,配合物表现较强的荧光增强作用,且在不同的温度下荧光增强常数Ks随温度的升高而降低,表明配合物与ct-DNA的作用机理是静态增强过程。根据双对数方程计算出了不同温度下的结合常数K和结合位点数n。稳态荧光猝灭及溴化乙锭(EB)竞争取代实验研究表明配合物与ct-DNA可能以嵌插方式结合。吸收光谱表明配合物增加了DNA双螺旋结构的稳定性。     

漫反射光谱测定云南元谋盆地古红土铁氧化物

铁氧化物矿物是现代土壤和古土壤的重要组成,其数量和形态是反映土壤成土条件和土壤风化发育程度的重要指标。鉴于其粒度细小、结晶度差、含量低、与粘土矿物密切共生, 加之基体效应的影响,难以快速准确测定其含量;鉴于某些测试方法自身的限制,能用于铁氧化物矿物定量分析的方法也很少。在分析目前常用测量方法的基础上,选择漫反射光谱法（DRS）对云南元谋盆地所采古红土样品中的铁氧化物进行定量研究,结果表明：漫反射光谱法测得土壤样品在400~2 500 nm之间,间隔2 nm共1 061个波段的光谱反射率最高45%左右,各样品反射率特征较为一致;漫反射光谱一阶导数显示,光谱主峰位于575 nm处,为赤铁矿的指示波谱段,次级峰位于435 nm处,为针铁矿的指示波谱段;确定云南元谋古红土存在赤铁矿和针铁矿,其含量范围3~5和5~10 g·kg-1,此结果获得XRD方法分析方法的佐证。     

以UV胶为纤芯本底的CdSe/ZnS量子点光纤光致荧光光谱的传光特性

制备了一种以紫外（UV）固化胶为纤芯本底的CdSe/ZnS量子点掺杂光纤.通过测量不同掺杂浓度和光纤长度下的量子点光致荧光光谱,得到了荧光峰值强度与量子点掺杂光纤浓度和长度的关系,确定了UV胶纤芯本底下的量子点的吸收系数、合适的掺杂浓度和光纤长度.结果表明|UV胶在光纤中具有吸收小、收缩率低、与石英光纤包层折射率匹配、性能稳定等特点,是一种比较理想的实验室制备量子点光纤纤芯本底的材料.     

Ethylene polymerization and ethylene/hexene copolymerizaion with vandium catalysts bearing thiophenolphosphine ligands

Vanadium(Ⅲ) complexes bearing thiophenol-phosphine ligands (2a-2b) (2-R-6-PPh2-C6H2S) VCl2(THF)2 (2a: R=H; 2b: R=Me3Si) were prepared from VCl3(THF)3 by treating with 1.0 equiv of the ligand in tetrahydrofuran in the presence of excess triethylamine. The two complexes were characterized by FTIR and mass spectra as well as elemental analyses. On activation with Et2AlCl, these complexes exhibited high catalytic activities (up to 22.1 kg PE/(mmolV·h·bar)) even at high temperature (70℃), and produced high molecular weight polymers with unimodal molecular weight distributions, indicating the polymerization took place in a single-site nature. This result may be attributed to benefits of introduction of second-row donor atoms for adjusting charge density of the vanadium centers. In addition, these complexes also exhibited high catalytic activities for ethylene/1-hexene copolymerization. Catalytic activity, comonomer incorporation and polymer molecular weight can be controlled in a wide range by the variation of catalyst structure and the reaction parameters such as Al/V molar ratio, comonomer feed concentration and polymerization reaction temperature.     

城市河道系统的景观敏感性与景观规划

运用景观生态学的原理,通过对城市河道系统的景观敏感性与视觉美学敏感性的分析,指出景观系统的敏感性是指不同时间和空间尺度上系统对干扰的反应.揭示了城市化的快速发展使土地利用方式发生大规模改变的同时,城市河道及其沿岸景观系统在结构、形态上也发生巨大变化,导致河流水文、生态系统的破坏与功能的退化,城市水文洪涝灾害频发、水质污染严重和美学质量下降等问题,提出用景观规划探讨城市河道系统的保护、修复与补偿系统及可持续发展途径.     

离心泵叶片压力面固液两相流的边界层分析

给出了离心泵叶片压力表面固液两相流体边界层控制方程和叶片压力面边界层分离参考点位置估算的一种方法,通过实例计算分析了相关的边界层参数,计算结果说明固液两相流的边界层厚度δ2随叶片弯曲系数Kν的减低和随质量浓度ρm的增加而减薄,并给出了对比试验的验证结果,结果是大于临界速度系数的叶片将使测试泵的性能有不同程度的下降,并且测试浓度的增加有抑制边界层分离的作用。它说明离心泵叶片压力面两相流边界层分离点的位置是随叶片形状的改变而移动的,是可以控制的。     

Analytical modeling of sandwich beam for piezoelectric bender elements

Piezoelectric bender elements are widely used as electromechanical sensors and actuators.An analytical sandwich beam model for piezoelectric bender elements was developed based on the first-order shear deformation theory(FSDT),which assumes a single rotation angle for the whole cross-section and a quadratic distribution function for coupled electric potential in piezoelectric layers,and corrects the effect of transverse shear strain on the electric displacement integration.Free vibration analysis of simply- supported bender elements was carried out and the numerical results showed that,solu- tions of the present model for various thickness-to-length ratios are compared well with the exact two-dimensional solutions,which presents an efficient and accurate model for analyzing dynamic electromechanical responses of bender elements.     

以UV胶为纤芯本底的CdSe/ZnS量子点光纤光致荧光光谱的传光特性

制备了一种以紫外(UV)固化胶为纤芯本底的CdSe/ZnS量子点掺杂光纤.通过测量不同掺杂浓度和光纤长度下的量子点光致荧光光谱,得到了荧光峰值强度与量子点掺杂光纤浓度和长度的关系,确定了UV胶纤芯本底下的量子点的吸收系数、合适的掺杂浓度和光纤长度.结果表明:UV胶在光纤中具有吸收小、收缩率低、与石英光纤包层折射率匹配、...