液膜萃取法回收废胶体钯活化液中的钯

传统钯回收方法存在成本高、分离效率低,适合高含量钯回收等问题,试验采用液膜萃取法回收废胶体钯活化液中的钯,并考察了内相试剂用量、流动载体用量、表面活性剂用量、油内比、乳水比、外相酸碱度等因素对钯萃取率的影响.结果表明:以9％N503、4％Span80、2％液体石蜡、85％磺化煤油组成膜相,内相试剂EDTA溶液浓度为0....     

Preparation of colloidal gold particles of various sizes using sodium borohydride and sodium cyanoborohydride

The activity of the major intracellular protein phosphatase, protein phosphatase 2A (PP2A), is determined by the nature of the associated regulatory subunit. A new family of human PP2A regulatory subunits has recently been identified. Three of these subunits, B56beta, B56delta, and B56epsilon, are most highly expressed in brain, while the B56alpha and B56gamma isoforms are highly expressed in cardiac and skeletal muscle. Genes PPP2R5A-PPP2R5E encoding the phosphatase regulatory proteins B56alpha, B56beta, B56gamma, B56delta, and B56epsilon have now been mapped by fluorescence in situ hybridization to chromosome regions 1q41, 11q12, 3p21, 6p21.1, and 7p11.2 --> p12, respectively.     

Structure of particles of very finely divided electrolytic iron

Conclusions X-ray structural analysis and electron microscopy have been employed to study the sizes and crystalline structures of particles of very fine iron powders produced in a two-layer bath using direct and pulsed currents and in a bath with an ultrasound-emitting cathode. The study has demonstrated that the superposition of an additional perturbance (an ultrasonic field or a pulsed current supply) on the electrolysis process restricts the growth of microcrystals and decrease their size variation compared with particles produced by electrolysis using a direct current. The character of curves of some structural characteristics of very fine iron powders plotted against the parameters of electrolysis in a two-layer bath with the use of a direct current, an ultrasound emitting cathode, and a pulsed current is evidence that iron particle formation in these variants of the electrolytic process occurs through different mechanisms.Translated from Poroshkovaya Metallurgiya, No. 5(257), pp. 1–6, May, 1984.     

钯及钯合金饰品标准样品的研制

遵循国家标准的标准样品工作导则,研制了一套适用于X射线荧光光谱法分析的钯和钯合金饰品标准样品,共5种。按成分的梯度要求,将金属原料混合后熔融,成分合格后铸成厚度为0.18~0.24 mm,直径为16 mm的圆片。利用方差法对均匀性数据进行检查,并委托8家实验室采用不同的实验方法进行定值分析,分析数据用狄克逊检验和夏皮罗-威尔克方法进行检验,结果表明本套标准样品的均匀性良好,定值结果准确。本套标准样品已用于X-射线荧光光谱分析,并被批准为国家标准样品。     

Recovery of palladium from palladium phthalocyanine complex adsorbed on silica

This study presents the feasibility of recovering palladium from the spent silica waste wherein palladium is adsorbed on silica as palladium phthalocyanine complexes. The spent silica having palladium phthalocyanine complexes adsorbed on it is thermally calcined in air to partially burn the organic moiety of the complex followed by palladium dissolution as H₂PdCl₄ in hydrochloric acid. The palladium is recovered as PdCl₂ by judiciously adjusting the pH of filtrate obtained. Recovered silica retains its structure and can be re-used.     

Optical slicing and 3-D characterization of hippocampal capillaries in the rat visualized by autometallographic silver enhancement of colloidal gold particles

In order to visualize the vascular system of the rat brain, 10 Wistar rats were perfused transcardially with glutaraldehyde and a 40 degrees C gold-gelatine solution. The brains were post-fixed with glutaraldehyde and vibratomized into 100-micron-thick slices, and the gold particles were developed by autometallography. In this way, the colloidal gold particles in the vessels became encased in silver and thereby made visible. The developed gold staining is stable and does not interfere with further dehydration and counterstaining. Images were frame grabbed during optical slicing, and classic stereograms and 'shadow' 3-D images were produced. We found a high variation of capillary density in the hippocampal region reflecting known subregional structures. The silver-enhanced vessels acted as natural markers and made it possible to study and measure aspects of the complexity of dehydration and staining artifacts. We found a non-linear shrinking of 13-17% in the x- and y-directions and a spatial shrinking up to 50% in some regions after the dehydration and staining process. This observation may be of interest not only in relation to tissue subjected to this fixation protocol but also to other fixation procedures. The gold-gelatine autometallographic technique and the present stereograms can release data for stereological use as well.