激光等离子体中超金属氧化物离子LiZnO+的产生

作为一般规律 ,在一些具有热力学稳定性的氧化物分子中 ,氧原子周围共价电子数为 8.自从发现 Li3O和 Li4 O分子以来 ,这类超过 9个或更多共价电子的含金属团簇小分子呈现出来的特殊化学计量比和热力学稳定性引起人们的关注 ,人们称其为超共价分子 (Hypervalent Molecules)或超金属分子(Hypermetallic Molecules) [1～ 4 ] .目前 ,在实验上已发现了 Mn O,Mn S及 Mn C(M=Li,Na,K,Mg;n≥ 3 )等一系列超金属分子 ;在理论上 ,从头计算法已可计算出超金属分子的结构及其稳定性 ,使人们对这些超金属分子的产生与结构有一定的认识 .然而 ,由…     

电感耦合等离子体质谱法测定磷酸钡激光玻璃中超痕量铜

将高纯HF-HNO3组合试剂与高纯PFA低压密闭消解罐建立了针对目标高温烧结体的简洁、快速、低本底湿法样品处理流程。系统优化了组合消解试剂的用量和配比、样品消解温度和消解时间等因素,实现了在150℃消解温度时1.7 m L的总试剂消耗量下样品完全分解总耗时小于1 h,且无需对样品破碎至细颗粒,大大降低了样品制备中的玷污风险。以水杨醛肟类作萃取剂,建立了高效液液萃取分离富集法。以5 m L15%的萃取剂浓度在0.5%HNO3的萃取酸度和20%HNO3反萃取酸浓度下,实现了99.999%的基体分离效率,Cu2+富集10倍。优化了电感耦合等离子体质谱(ICP-MS)测定参数,在840 W低功率和低样品提取量时实现20%HNO3酸度下铜的高信背比检测,全流程方法检出限2.5 ng/g,平行测定RSD(n=6)为3.3%,加标回收率94.3%。基于所建立的方法实现了实际样品的准确测定,得出铜含量与激光能量衰减实验结果线性相关的结果。     

四种同分异构的四环稠环芳烃的激光等离子体质谱分析

在常规质谱中,各种同分异构的稠环芳香烃基本上无法分辨。但在本文报道的以近红外脉冲激光所产生的等离子体质谱中,所分析的四个四稠环芳香烃尽管分子量相同,其负离子质谱却有十分明显的差异,显示了这一研究方法的结构鉴别能力。     

纳秒激光电离产生Kr17+的研究

Up to Kr17 + multicharged krypton ions have been observed in time-of-flight mass spectrum by a 25 ns Nd-YAG 1. 064 μm laser at laser intensity about 1012 W/ cm2 . Experimental results indicate that the multicharged ions appear only when the laser interacts with the middle part of the pulsed beam,and the intensities of the multicharged ions increase dramatically by increasing the backing pressure of Kr gas,which indicates that the clusters in the beam is essential to the production of multicharged ions. From the experimental results,it is concluded that the cluster is ionized via multiphoton ionization and forms a nanoplasma ball,which can absorb the laser resonantly to further ionize the single charge ion to the high charge state.     

复合物Mg＋-NCSCH3, Ca＋-NCSCH3光解离光谱研究

研究了复合物Mg^＋-NCSCH₃在230～440 nm波段和Ca^＋-NCSCH₃在320～560 nm波段的光解离光谱. 复合物Mg^＋-NCSCH₃, Ca^＋-NCSCH₃光诱导反应的产物质谱表明有非反应猝灭产物Mg^＋(Ca^＋), C—S键断裂产物Mg^＋(Ca^＋)NC 和Mg^＋(Ca^＋)NCS以及重排反应产物Mg^＋(Ca^＋)-CHSH通道. 在原子跃迁谱线(3²S→3²P, 对于Mg^＋; 4²S?4²P, 对于Ca^＋)的红和蓝两边, Mg^＋-NCSCH₃的光解离光谱由两个宽峰组成; 而对于Ca^＋-NCSCH₃, 则是由三个谱峰构成. CIS/6-311＋＋G^**等级上, 对应于基态构型的Mg^＋-NCSCH₃电子态跃迁能量和振子强度与实验光谱较为一致; 而Ca^＋-NCSCH₃有较大的差别. 这是因为CIS方法忽略电子相关效应, 而Ca^＋-based的跃迁中3d和4s轨道间存在较强的混合所致.     

复合物Mg＋-NCSCH3, Ca＋-NCSCH3光解离光谱研究

研究了复合物Mg^＋-NCSCH₃在230～440 nm波段和Ca^＋-NCSCH₃在320～560 nm波段的光解离光谱. 复合物Mg^＋-NCSCH₃, Ca^＋-NCSCH₃光诱导反应的产物质谱表明有非反应猝灭产物Mg^＋(Ca^＋), C—S键断裂产物Mg^＋(Ca^＋)NC 和Mg^＋(Ca^＋)NCS以及重排反应产物Mg^＋(Ca^＋)-CHSH通道. 在原子跃迁谱线(3²S→3²P, 对于Mg^＋; 4²S?4²P, 对于Ca^＋)的红和蓝两边, Mg^＋-NCSCH₃的光解离光谱由两个宽峰组成; 而对于Ca^＋-NCSCH₃, 则是由三个谱峰构成. CIS/6-311＋＋G^**等级上, 对应于基态构型的Mg^＋-NCSCH₃电子态跃迁能量和振子强度与实验光谱较为一致; 而Ca^＋-NCSCH₃有较大的差别. 这是因为CIS方法忽略电子相关效应, 而Ca^＋-based的跃迁中3d和4s轨道间存在较强的混合所致.     

激光溅射Ni等离子体与气相CH3OH团簇的反应

The gas phase reaction of Ni plasma and methanol clusters is studied by the laser ablation-molecular beam（LAMB） method. Five species of clustered complex ions Ni+（CH3OH）n,NiO+（CH3OH）n,H+（CH3OH）n,H3O+（CH3OH）n,CH3O-（CH3OH）n（n≤25）are observed. Interestingly,the species and sizes of the product clusters vary observably when the plasma acts on the different parts of the pulsed methanol molecular beam. When the laser ablated Ni plasma acts on the head and tail of the beam,the metal methanol complex clusters Ni+（CH3OH）n and the oxidation clusters NiO+（CH3OH）n（n=1-15）together with protonated methanol clusters H +（CH3OH）n are domain. While the plasma acts on the middle of the beam,however,Ni+（CH3OH）1-2 and H+（CH3OH）n along with the mixed methanol-water clusters H3O+（CH3OH）n（n=15-25）turn to be the main resulting clusters. By comparing the intensities and the cluster sizes of NiO+（CH3OH）n with Ni+（CH3OH）n,the formation of NiO+（CH3OH）n is contributed to the intracluster demethanation reaction of Ni+（CH3OH）n and evaporation of several methanol molecules. As the H3O+（CH3OH）n is observed only when the plasma acts on the high density part of the beam,and their intensities are only 0. 5% of the protonated methanol molecule,it is concluded that the species are partially due to the recombination of H+（CH3OH）n and water,which come from the plasma-molecule reaction.     

激光溅射Cu等离子体与气相CH3CN团簇的反应

The gas phase reaction of Cu plasma and acetonitrile clusters is studied by the laser ablation-molecular beam（LAMB） method. Four series of clustered complex ions Cu+（CH3CN）n, CH2CN+（CH3CN）n,H+（CH3CN）n and CH3CHCN+（CH3CN）n are observed. Interestingly,the species and sizes of the product clusters vary observably when the plasma acts on the different parts of the pulsed acetonitrile molecular beam. When the laser ablated Cu plasma acts on the head of the beam,the metal acetonitrile complex clusters Cu+（CH3CN）n together with protonated acetonitrile clusters H+（CH3CN）n and deprotonated acetonitrile clusters CH2CN+ （CH3CN）n are domain,while the plasma acts on the middle of the beam. However,CH2CN+（CH3CN）n and H+（CH3CN）n along with the clusters CH3CHCN+（CH3CN）n turn out to be the main resulting clusters. By comparing the intensities and the cluster sizes of CH3CHCN+（CH3CN）n with H+（CH3CN）n and CH2CN+（CH3CN）n,the formation of CH3CHCN +（CH3CN）n is contributed to the intracluster ion-molecule reaction of acetonitrile clusters.     

激光溅射金属等离子体与醇类分子束反应的研究：产物离子对分子束状态的依赖性

The gas phase reactions of metal plasma with alcohol clusters were studied by time of flight mass spectrometry （TOFMS） using laser ablation-molecular beam （LAMB） method. The significant dependence of the product cluster ions on the molecular beam conditions was observed. When the plasma acted on the low density parts of the pulsed molecular beam, the metal-alcohol complexes M^＋An （M=Cu, Al, Mg, Ni and A=C2H5OH, CH3OH） were the dominant products, and the sizes of product ion clusters were smaller. While the plasma acted on the high density part of the beam, however, the main products turned to be protonated alcohol clusters H^＋An and, as the reactions of plasma with methanol were concerned, the protonated water-methanol complexes H3O^＋（CH3OH）n with a larger size （n≤12 for ethanol and n≤24 for methanol）. Similarly, as the pressure of the carrier helium gas was varied from 1 × 10^5 to 5 × 10^5 Pa, the main products were changed from M^＋An to H^＋An and the sizes of the clusters also increased. The changes in the product clusters were attributed to the different formation mechanism of the output ions, that is, the M^＋An ions came from the reaction of metal ion with alcohol clusters, while H^＋An mainly from collisional reaction of electron with alcohol clusters.     

Formation of complexes of Rubisco-Rubisco activase from La3+, Ce3+ treatment spinach

The complex of Rubisco and Rubisco activase from LaCl₃ ^™, CeCl₃ ^™ treated spinachin vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl₃ ^™, CeCl₃ ^™ treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl₃ ^™, CeCl₃ ^™ treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl₃ ^™, CeCl₃ ^™ treated spinach are 1.8 and 2.8 times that of the control, the intensities of absorption and fluorescence are significantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 36–39 ™SH per mol enzyme, 14–25 ™SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl₃ ^™, CeCl₃ ^™ treated spinach is very different from the control. The enzyme activities from LaCl₃ ^™, CeCl₃ ^™ treated spinachin vivo are 1.5 and 1.9 times those of the control.     

N4+的生成与检测

用从Nd:YAG激光器发出的波长532nm的激光(能量约为10mJ/pulse)溅射由BN、ZrN粉末分别压成的直径13mm、厚度约2～5mm的固体压片样品,生成了含氮团簇N4+。实验中,用高纯氮气为载气,辅助含氮团簇的生成并冷却激光溅射所产生的团簇。反射式飞行时间质谱仪监测反应过程证实N4+的存在,且其存在时间超过200μs。     

BaY2F8∶Ce, Eu中Ce3+→Eu2+的能量传递和Ce3+→Eu3+的电子转移

采用高温固相反应法制备了BaY     

Zur elektrochromatographischen Trennung von Y3+, La3+, Ce3+, Pr3+ und Nd3+

Ohne Zusammenfassung     

Die Reaktion von Arsenazo III mit H+, La3+, Sm3+, Gd3+, Dy3+ und Yb3+

Ohne Zusammenfassung     

Complexing ability of pesticides and related compounds. Formation and stability in aqueous solution of H+ , Li+, Na+, K+, Mg2+ and Ca2+ phenoxyacetate complexes at different temperatures and ionic strengths

The formation constants of Li⁺, N⁺, K⁺, Mg²⁺ and Ca²⁺ phenoxyacetate complexes were determined potentiometrically using an (H⁺)-glass electrode at 10, 25, 37 and 45°C, at several ionic strengths, in the range 0.04?I? 0.9 mol 1^?1. Simple empirical equations for the dependence of the formation constants on ionic strength were derived. From the temperature coefficients, estimates of ΔH^o and ΔS^o were obtained.     

The pair polarizabilities of Li+/Li+ and Cl−/Cl−

Ab initio SCF MO energies and pair polarizabilities are reported for the pairs Li⁺/Li⁺ and Cl^?/Cl^? over the ranges of internuclear separation which are of importance in molten LiCl. The shapes of the β(R) curves resemble those of inert gas diatoms. The Cl^?/Cl^? interaction is predicted to make a rather small contribution to those properties of molten LiCl which depend on $\text{α}$⁽²⁾(R), and a larger contribution to properties which depend on β(R). The Li⁺/Li⁺ interaction contributes almost nothing to the bulk polarizability.     

Die Verteilungkoeffizienten von TiO2+, Cr3+, Mn2+ und Fe3+

Ohne Zusammenfassung     

Solvent extraction of H3O+, NH4+, Ag+, K+, Rb+ and Tl+ into nitrobenzene by using cesium dicarbollylcobaltate in the presence of a hexaarylbenzene-based receptor

From extraction experiments and γ-activity measurements, the extraction constants corresponding to the general equilibrium M⁺(aq) + 1·Cs⁺(nb) \rightleftarrows \rightleftarrows 1·M⁺(nb) + Cs⁺(aq) taking part in the two-phase water–nitrobenzene system (1 = hexaarylbenzene-based receptor; M⁺ = H₃O⁺, NH₄ ⁺, Ag⁺, K⁺, Rb⁺, Tl⁺; aq = aqueous phase, nb = nitrobenzene phase) were evaluated. Furthermore, the stability constants of the ML⁺ complex species in nitrobenzene saturated with water were calculated; they were found to increase in the series of Rb⁺ < K⁺ < Ag⁺, Tl⁺ < H₃O⁺, NH₄ ⁺.