Extraction of Cesium from the Irradiated Nuclear Waste by 4(5),4''''(5'''')-Bis[1-hydroxyalkylbenzo]-21-crown-7

The fission product 137Cs accounts for a large fraction of the radioactivity in high-levelnuclear waste (HLW). Because of the hazard to environment and the widespreadapplication of 137Cs gamma radiatior1, a need has arisen to develop improved methods forthe removal and recovery of radiocesium from these wastes. Reports have shown thatsome calixcrown compounds may be highly selective for Cs cation2, but, since thesynthesis of them is difficult and the cost is high, it might obviate their use…     

Determination of Thyroxine with Capillary Electrophoretic Enzyme Immunoassay

Capillary electrophoretic immunoassay (CEIA) is a new analytical technique1,2. In CEIA, the detection methods were UV absorbance detection1 and laser induced fluorescence detection (LIF)2. However, The UV detection is lack of sensitivity. The LIF is difficult to use due to its high cost, and furthermore, most biological fluids are strongly luminescent when excited by the laser in the blue or green region of the spectrum. In our present work, a capillary electrophoretic enzyme immuno…     

Indirect Flow Injection Chemiluminescence Method for the Determination of Tetracyclines Using Cu(Ⅱ) as a Probe Ion

Tetracycline antibiotics (TCs) are active against a wide range of gram-positive and gram-negative bacteria, being extensively used in human and veterinary medicine to treat and prevent bacterial infections1. Among the TCs, TC, OTC and CTC are commercially available and permitted for human administration. However, the degradation products occurring in storage conditions might induce potential adverse effects. Thus, many studies have focused on the development of a rapid, sensitive and reli…     

INTERACTION-MEDIATED GROWTH OF CARBON NANOTUBES ON ACICULAR SILICA-COATED a-Fe CATALYST BY CHEMICAL VAPOR DEPOSITION BY CHEMICAL VAPOR DEPOSITION

1. Introduction Carbon nanotubes (CNTs), a kind of the most advanced nanomaterials with novel properties and promising for many applications, have aroused great interest of the world in a number of research fields (Iijima, 1991; Baughman et al., 2002; Iijima & Ichihashi, 1993; Rao & Govindaraj, 2002; Rueckes et al., 2000; Adrian et al., 2001; Javey et al., 2003). Catalytic chemical vapor deposition (CCVD) is re-garded as the most suitable method for the preparation of microstructured CN…     

NUMERICAL SOLUTION OF THE SINGULARLY PERTURBED PROBLEM WITH NONLOCAL BOUNDARY CONDITION

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｉｓｐａｐｅｒｉｓｃｏｎｃｅｒｎｅｄｗｉｔｈｔｈｅｎｕｍｅｒｉｃａｌｓｏｌｕｔｉｏｎ ,ｂｙｆｉｎｉｔｅｄｉｆｆｅｒｅｎｃｅｍｅｔｈｏｄ ,ｏｆｔｈｅｆｏｌｌｏｗｉｎｇｓｉｎｇｕｌａｒｌｙｐｅｒｔｕｒｂｅｄｎｏｎｌｏｃａｌｂｏｕｎｄａｒｙｖａｌｕｅｐｒｏｂｌｅｍ :Ｌｕ≡-εｕ″ +ａ(ｘ)ｕ=ｆ(ｘ)　　 ( 0 <ｘ<ｌ) ,( 1 )Ｌ0 ｕ≡-εｕ′( 0 ) +γｕ( 0 ) =μ0 , ( 2 )Ｌ1ｕ≡ｕ(ｌ) -δｕ(ｄ) =μｌ　　 ( 0 <ｄ<ｌ) ,( 3 )ｗｈｅｒｅεｉｓａｓｍａｌｌｐｏｓｉｔｉｖｅｐａｒａｍｅｔｅｒ,…     

Synthesis of Cubic Mesoporous Silica MCM-48by Mixed Micellar Templates

In 1992, Mobil researchers introduced a novel concept in the synthesis of mesoporous silicas (M41S)1,2 by using a self-assembled molecular array of surfactant molecules as structure-directing template. Depending on the shape of their templates and the respective resulting pore structure, the M41S family was identified : MCM-41(hexagonal), MCM-48(cubic), and other species. MCM-41 with honeycomb arrays of nonintersecting channels was shown to be the easiest to synthesize1. MCM-48 containin…     

nitial Potential" Effect on the Dissociative Adsorption of Methanol on A Roughened Platinum Electrode in Acidic Solution

The research of electrocatalytic oxidation of small organic molecules such as methanol, formaldehyde and formic acid has been fascinating electrochemists for more than thirty years, owing to its significance in energy conversion and reaction mechanisms. The surface adsorbed species involved in these electrocatalytic reactions, especially reactive and poisoning intermediates, have been investigated by electrochemical, spectroscopic and other physicochemical methods1. However, Raman spectrosco…     

On Vector Helmholtz Equation with a Coupling Boundary Condition

The Helmholtz equation is sometimes supplemented by conditions that include the specification of the boundary value of the divergence of the unknown.In this paper, we study the vector Helmholtz problem in domains of both C~(1,1)and Lipschitz.We es- tablish a rigorous variational analysis such as equivalence,existence and uniqueness. And we propose finite element approximations based on the uncoupled solutions.Fi- nally we present a convergence analysis and error estimates.     

p-Hydrazinobenzenesulfonic Acid Derivatives of Carbohydrates and Their Capillary Zone Electrophoresis

Precolumn derivatization is the most widely used means to overcome the detection problem in capillary electrophoresis. However most of the adopted reactions in carbohydrate labeling are time-consuming and not very selective, leading to lots of byproducts produced. We have thus tried to explored hydrazino-containing reagents which have been applied to TLC1,2 and HPLC2~5 with quite successfulness. Perez and Colón6 have also reported that dansylhydrazine can be used in CE-LIF of sugars. Th…     

Effect of Spacers on CMCs and Micelle-forming Enthalpies of Gemini Surfactants by Titration Microcalorimetry

Gemini surfactants, as a new generation of surfactants in 1990's1, are the surfactants with two polar groups and two alkyl chains connected with a spacer. The most widely studied gemini surfactants are as follows: [CmH2m+1N (CH3)2- (CH2)S -N (CH3 )2CmH2m+1] Br2, or Cm-CS-Cm(2Br -where Cs stands for its spacer. Studies on their interesting physico chemical properties2,3 have made much progress, predicting that the repulsive interaction between the two head groups, hydrophobic interactio…