Ni~(2+)对Cu~+-13X分子筛动态吸附脱硫性能的影响

采用液相离子交换法制备Cu+-13X和Ni2+/Cu+-13X分子筛吸附剂,运用X线衍射仪(XRD)、扫描电子显微镜(SEM)和傅里叶红外光谱仪(FT-IR)等对样品进行表征。在常温和常压下,通过固定床吸附实验研究Cu+-13X和Ni2+/Cu+-13X对含有噻吩(TP)、2-乙基噻吩(2-ETP)的双组分模拟汽油的动态吸附脱硫性能。结果表明:Ni2+/Cu+-13X分子筛中Ni2+质量分数为1.54%时,Ni2+/Cu+-13X分子筛吸附脱硫效果最佳。动态吸附实验过程中,噻吩类硫化物与2种吸附剂之间均存在π配位作用,且噻吩与2-乙基噻吩之间存在竞争吸附,而Ni2+可以增大Cu+-13X吸附剂对2-乙基噻吩的吸附选择性;负载的Ni可以作为一种助剂,增加Cu+-13X吸附剂对噻吩类硫化物的吸附量,在相同的实验条件下,经Ni2+改性后的Cu+-13X对噻吩和2-乙基噻吩的穿透吸附量和饱和吸附量分别增加了66.9%、35.5%和24.4%、18.2%。     

Al2 O3对连铸保护渣中氟浸出的影响

为了消除保护渣在使用过程中氟溶解到水中造成的危害,提出了开发高Al2 O3含量的保护渣.研究了不同含量的Al2 O3对保护渣熔渣水浸液中F-质量浓度和pH值的影响,并利用X射线光电子能谱分析了Al2 O3含量对保护渣熔渣结构的影响.当Al2 O3的质量分数为4%时,保护渣迁移到水中的F-质量浓度为22.8~35.4 mg·L-1,pH值的变化范围为4.0~9.5;当Al2 O3的质量分数由4%增加到34%,F-质量浓度和pH值的变化范围均是先急剧减小后略有增加的趋势. X射线光电子能谱分析显示：增加保护渣中Al2 O3的含量时,保护渣中Al2 O3通过形成Al—F共价键,抑制了氟的浸出.控制保护渣中Al2 O3的质量分数在16%~34%的范围,则实验水样中F-质量浓度在4.0~10.0 mg·L-1的范围,pH值在6.5~7.5的近中性范围,可减弱氟浸出造成的危害.     

自由基与肺癌发病机制

肺癌是严重影响人类健康的疾病,其发病机制目前尚未阐明.自由基医学是近年来兴起的一门交叉学科,本文对自由基在吸烟、职业烟尘微粒、金属离子、石英、石棉等理化因素致肺癌过程中的发病机制进行探讨.     

LiH+和LiH-势能函数与光谱参数的理论计算

用密度泛函理论B3LYP方法和6-311 G**基函数对LiH 和LiH-分子离子进行理论计算研究.结果表明,这两个分子离子的基态均为X2∑,其势能函数可以用Murrll-Sorbie来表达.通过势能函数参数得到分子离子的光谱数据.     

FAIMS迁移管中离子运动分析及迁移管结构的初步设计

根据牛顿第二定律,分析了离子在高场不对称波形离子迁移谱(High-Field Asymmetric Waveform Ion Mobility Spectrometry,FAIMS)迁移管中的受力及运动情况。当作用的电场大小和占空比一定时,离子在迁移管中的运动仅仅与其本身的性质有关,而当FAIMS迁移管周围存在磁场干扰时,离子处于电场和磁场的复合作用下而作余摆线运动。电场的作用使离子定向漂移,而磁场的干扰使离子的运动变得复杂,从而大大降低了FAIMS的可靠性和稳定性。为了降低磁场对迁移管中离子运动的干扰,提出了具有屏蔽电磁干扰的FAIMS迁移管结构。     

不同水分状况下云南松抗病性的研究(Ⅱ)

研究不同水分状况下云南松茎韧皮部多酚氧化酶（ＰＰＯ） 活性的变化情况发现,灌水处理后,ＰＰＯ 活性最低,干旱处理的最高;１ ～５ 月,随干旱程度的加深,ＰＰＯ 活性逐渐升高;接种蓝色伴生真菌后,ＰＰＯ 活性普遍升高,干旱处理的升幅最大,灌水处理的最小,适度干旱有利于提高云南松的抗病性．     

Ice core dust particulate by XPS-SEM/EDAX

The ice core dust particulate sampled from Mt. Xixabangma has been analyzed by means of X-ray photoelectron spectrometer (XPS) and scanning electron microscope with energy dispersion X-ray analysis (SEM/EDAX). The results show that the contents of SO ₄ ²⁻ and SO ₄ ²⁻ in the surface layer of the dust are significantly higher than those in the subsurface layer (with the exception of organic sulfide). This difference indicates that the surface SO_x has been captured and then chemically converted by the atmospheric dust particulate before its deposition with snow, which is obviously different from those inner layer sulfates and sulfites contained by dust itself. In addition, it has been determined by SEM/EDAX that the dust contains relatively high concentrations of transition metal elements such as Fe and Ti oxides which could function as photocatalysts to the conversion of SO_x adhered on the surface of the dust, and consequently accelerate the deposition of SO_x to snow. Our research also demonstrates that the adsorptive carrying and the catalytic performance of the dust to the atmospheric SO_x are most important causes of the positive correlation between SO ₄ ²⁻ and dust concentration records in ice cores.     

General kinetic model of imperfect living polymerization (Ⅳ)——Non-steady state analysis for reaction systems with two active speciesspecies

The living ionic polymerization with two active species was theoretically studied, presenting the expressions of the number- and weight-average degrees of polymerization and the polydispersity index. The numerical calculation shows that both steady state and non-steady state approaches result in the essentially same outcomes when the exchange rate between the two active species is larger than the rates of chain propagation; however, the steady state method leads to a larger error and only the non-steady state approach is valid if the exchange rate between the two active species is comparable to or smaller than propagation rates. In addition, the molecular weight distribution of the resulting polymer becomes narrower with the value of kp approaching to kp and with increasing M0/l0.     

重金属离子对扁玉螺细胞色素氧化酶的影响研究

测定子扁玉螺肝脏中细胞色素氧化酶活力,其最适温度为４４℃,最适ＰＨ值７．０研究了Ｆｅ＾３＋,Ｃｕ＾２＋,Ｚｎ＾２＋三种重金属离子在离体条件下对该酶的影响,结果显示：低浓度的Ｆｅ＾３＋Ｃｕ＾２＋对其具有激活作用,高浓度的Ｆｅ＾３＋,Ｃｕ＾２＋及低浓度的Ｚｎ＾２＋对其具有显著的抑制作用。     

氢氧化锌易溶于氨水吗？

本文应用热力学耦合反应的观点对氢氧化锌与氨水的反应进行了讨论,并指出ＮＨ４＾＋离子是促进溶解反应较易进行的主要因素。