Study on analysis of153Sm-EDTMP stability in vitro and vivo by HPLC

The behavior of¹⁵³Sm-EDTMP in vitro and vivo is analyzed by the size exclusion HPLC. The experimental results show that EDTMP amounts have an obvious effect on the stability in vitro and uptake of¹⁵³Sm-EDTMP in the liver. HPLC analysis of urine sample indicates that¹⁵³Sm-EDTMP es excreted in the original form. The behavior in vivo of¹⁵³Sm-EDTMP containing 4 μg is similar to that of¹⁵³Sm-EDTMP containing 50 μg EDTMP at 1 h post-injection.     

Synthesis and aggregation behavior of <Emphasis Type="Italic">N</Emphasis>-succinyl-o-carboxymethylchitosan in aqueous solutions

A simple and novel method was developed to successfully synthesize N-succinyl-O-carboxymethylchitosan (NSOCMCS) using N-acylation of chitosan with succinic anhydride. The NSOCMCS structure was characterized by Fourier transform infrared and ¹H nuclear magnetic resonance. The aggregation behaviors of NSOCMCS were studied using fluorescence spectroscopy, dynamic light scattering, and atomic force microscopy techniques. The critical aggregation concentration of NSOCMCS in water was determined to be 0.2–0.3 mg/ml. The apparent hydrodynamic radium of an NSOCMCS aggregate was dependent on the concentration. The aggregates demonstrated a much swollen association conformation in aqueous solution. The possible aggregation mechanisms for the NSOCMCS in water are discussed. Moreover, a driving force to form an open aggregation morphology was revealed in this study. Aggregation behaviors are important physicochemical properties of NSOCMCS, which impact the potential application in the biomedical field.     

Development of the FTIR properties of nano-structure silica gel doped with different rare earth elements,prepared by sol-gel route

Structural characteristics of pure silica gel (silica-xerogel, SiO₂) and silica gel doped with some rare earth elements (REEs) such as, praseodymium Pr³⁺, and Europium Eu³⁺, Erbium Er³⁺ and Holmium Ho³⁺ ions, with different concentrations ranging from 1 up to 6%, in the form of monolith materials were prepared by sol-gel technique, Using tetra-ethoxysilane as precursor materials, which are of particular interest for sol-gel integrated optics applications. Some structural features of sol-gel derived monolith are analyzed, namely the structure of nano-particle momolith samples, based on X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR). We show that the XRD spectra of α-crystobalite are obtained for the pure samples at 1100°C and even by doping with the four REEs ions.     

Mössbauer Spectroscopic Studies of Chlorostannate(II) Complexes in Frozen Aqueous Solutions

Mössbauer parameters of frozen aqueous solutions of Sn(ClO₄)₂ in 0.5 M HClO₄ did not change with the concentration of NaClO₄, so that it was used to keep the ionic strength at the desired level. When NaCl was added into Sn(ClO₄)₂ solutions, isomer shift did not change, but quadrupole splitting did. Therefore, stability constants were calculated from the quadrupole splitting data, which were in good agreement with the published values. The observed spectra could be resolved into components.     

反相高效液相色谱法的多波长同时测定预混合饲料中的脂溶性维生素A，α－E，D_3，K_3

反相高效液相色谱法的多波长同时测定预混合饲料中的脂溶性维生素Ａ，α－Ｅ，Ｄ＿３，Ｋ＿３李桂凤，李缙扬，郝征红，聂燕，孟兆宏，李学春（山东省农业科学院中心实验室济南２５０１００）１前言对脂溶性维生素的分析，被许多国内外分析专家认为是高难度的分析项目。本...     

Radiation Effects on Concentrated Potassium Hexacyanoferrate(III) Solutions

The neutron irradiated potassium hexacyanoferrate(III) solutions were analyzed for Fe(CN)₆^4?, Fe(CN)₆^3?, and Prussian blue. The retention values (1.1%) were constant throughout the pH and concentration ranges studied, and did not change with the length of irradiation. The complex behavior of the radiochemical yield of the Fe(CN)₆^4? and Prussian blue was attributed to the competition of the various reactions involved in the irradiation.     

GC/MS法分析奶油中的脂肪酸

利用气相色谱/质谱/计算机联用技术分析人造奶油、天然奶油和新西兰奶油中的脂肪酸,从中鉴定出7种酸:棕榈酸、棕榈油酸、硬脂酸、油酸、亚油酸、亚麻油酸及花生酸。人造奶油含亚油酸比天然奶油含的高。     

Phase separation in the formation of hollow particles by suspension polymerization for divinylbenzene/toluene droplets dissolving polystyrene

Phase-separation behavior within polymerizing divinylbenzene/toluene droplet dissolving polystyrenes (PS) was investigated to clarify the formation mechanism of the hollow polymer particles by suspension polymerization. No hollow particles were obtained at a low content of low-molecular-weight PS where phase separation occurred at high conversion. On the other hand, hollow particles were obtained at a high content of high-molecular-weight PS where phase separation occurred at low conversion. The phase separation in an early stage of the polymerization, which was promoted by the presence of PS and cross-links of polydivinylbenzene, was a key factor for the formation of the hollow structure.     

Comparative X-ray photoelectron spectroscopic study on the desulfurization of thiophene by Raney nickel and rapidly quenched skeletal nickel

The desulfurization of thiophene on Raney Ni and rapidly quenched skeletal Ni (RQ Ni) has been studied in ultrahigh vacuum (UHV) by X-ray photoelectron spectroscopy (XPS). The Raney Ni or RQ Ni can be approximated as a hydrogen-preadsorbed polycrystalline Ni-alumina composite. It is found that thiophene molecularly adsorbs on Raney Ni or RQ Ni at 103 K. At 173 K, thiophene on alumina is desorbed, while thiophene in direct contact with the metallic Ni in Raney Ni undergoes C-S bond scission, leading to carbonaceous species most probably in the metallocycle-like configuration and atomic sulfur. On RQ Ni, the temperature for thiophene dissociation is about 100 K higher than that on Raney Ni. The lower reactivity of RQ Ni toward thiophene is tentatively attributed to lattice expansion of Ni crystallites in RQ Ni due to rapid quenching. The existence of alumina and hydrogen may block the further cracking of the metallocycle-like species on Raney Ni and RQ Ni at higher temperatures, which has been the dominant reaction pathway on Ni single crystals. By 473 K, the C 1s peak has disappeared, leaving nickel sulfide on the surface.     

Ordered nickel oxide nanowire arrays and their optical absorption properties

Ordered NiO nanowire arrays embedded in anodic alumina membranes have been prepared by using an electrochemical deposition method. After annealing at 300 °C, the NiO nanowire arrays were characterized using SEM, TEM, SAED, and XRD. SEM and TEM observations reveal that these nanowires are dense, continuous and arranged roughly parallel to one another. XRD and SAED analysis together indicate that these NiO nanowires crystallize with a polycrystalline structure. The optical absorption band gap of NiO nanowire arrays is 3.74 eV, and no obvious blue shift or red shift with respect of that of the bulk NiO can be observed.