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  • Author or Editor: H. Jin x
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Abstract  

The glass formation and devitrification of GaF3-based glasses were studied by differential scanning calorimetry. A comparison of various simple quantitative methods to assess the level of stability of multicomponent fluoride glass systems is presented. Most of these methods are based on critical temperatures. In this paper a new parameter k b(T) is added to the stability criteria. The stability of several GaF3-based glasses were experimentally evaluated and correlated with the activation energies of crystallization via this new kinetic criterion and compared with those evaluated by other criteria.

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Abstract

Thermal decomposition of N,N′-diphenylguanidine (DPG) was investigated by simultaneous TG/DSC-FTIR techniques under nonisothermal conditions. Online FTIR measurements illustrate that aniline is a major product of DPG decomposition. The observation that the activation energy depends on the extent of conversion indicates that the DPG decomposition kinetics features multiple processes. The initial elimination of aniline from DPG involves two pathways because of the isomerization of DPG. Mass spectrometry and thin film chromatography suggest that there are two major intermediate products with the major one of C21N3H17. The most probable kinetic model deduced through multivariate nonlinear regression method agrees well with the experimental data with a correlation coefficient of 0.9998. The temperature-independent function of conversion f(α), activation energy E and the pre-exponential factor A of DPG decomposition was also established through model-fitting method in this research.

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Abstract  

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.

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Abstract  

DTPA-Octreotide(Pentetreotide), a somatostatin analogue which can bind specifically and with high affinity to somatostatin receptor in vitro and vivo, labeled with99mTc by tin reduction in acetate buffer, has been characterized by Reverse-phase High performance Liquid Chromatography. The effect of different solvents, mobile phase pH, linear gradient and the injected volume on the separation efficiency was evaluated. The results show that the separation efficiency is best using μBondapak-C18 (300×3.9 mm2), linear gradient of 40% to 80% methanol (1.0 ml/min) in 0.05M acetate buffer (pH 5.5) over a 30 min period and maintaining for another 10 min. The labeled product is a mixture which mainly consists of five components (a, b, c, d, e) successfully proved by HPLC. Paper chromatography is also evaluated in this paper. It may be used to determine the radiochemical purity of the labeling product, but is not a good choice for the verification each components.

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Abstract  

Hydrogen gas (H2) was produced by gamma-irradiation of pure water in the presence of various TiO2 catalysts. Most catalysts used in this work largely enhanced the radiolytic decomposition of water and subsequent production of H2. The different activity of catalysts was characterized by X-ray diffraction (XRD) patterns and by electron paramagnetic resonance (EPR) spectra. The addition of methanol as a sacrificing agent further increased the H2 production by scavenging hydroxyl radicals and the scavenging activity was directly identified using an EPR/spin-trapping technique. Among the catalysts studied, nanosized TiO2 (nTiO2) showed an excellent activity in the production of H2. Furthermore, the addition of EDTA instead of methanol largely increased the H2 production. This is quite promising since waste compounds such as EDTA can be removed with concomitant H2 production

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The study investigated the effects of environmental factors (salinity, pH, ions and activation media) on sperm motility (activation rate, duration of quick movement, and lifespan) and fertilization rate of Phascolosoma esculenta. The results showed that spermatozoa in the coelom and nephridium are able to move quickly. The optimal salinity was 14.64 to 43.35 and the optimal pH was 6.46 to 9.53 for sperm activation and motility, whereas the ranges for fertilization were narrower (18.56 to 30.3 for salinity and 6.46 to 8.61 for pH). Of the ions studied, Na+ was indispensable for sperm motility and fertilization, and Ca2+ and Mg2+ were necessary for fertilization. P. esculenta sperm could not fertilize eggs and have short lifespans in 200 to 600 mmol/L NaCl and KCl solutions. Furthermore, they could not be activated or move in 200 to 600 mmol/L CaCl2, MgSO4, and sucrose solutions.

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Stem rust caused by Puccinia graminis f. sp tritici of wheat (Triticum aestivum L.) is one of the most destructive cereal diseases globally. Concern about the disease has increased since 1999 with the discovery in Uganda of a new virulent race of Pgt, designated as race TTKSK (also known as Ug99). The objectives of this experiment were to characterize the resistance and to determine the chromosomal location of the stem rust resistance in the spring wheat line PI 410966. A mapping population was developed from a cross between PI 410966 and a susceptible wheat line OK3040. An inoculation test with isolate 04KEN156/04 of race TTKSK was conducted at the USDA-ARS Cereal Disease Laboratory in the F6:7 generation, and the F6:7 phenotypic data were used to genetically map the resistance gene to the centromeric region on chromosome 2BS. The single locus explained the observed F6:7 resistant and susceptible scores. The location of the gene and molecular marker banding profiles of the diagnostic markers suggest that the stem rust resistance gene in PI 410966 could be a new gene, an allele of Sr36, or Sr36.

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Abstract  

The preparation of a cold kit was introduced in the paper, and the effective quantities of the components (Vc, HEDP and SnCl2·2H2O) in the kit were determined. At the sametime, the effects of labelling kit on the reaction time, reaction temperature and animal distribution were studied in detail. The initial animal experiment showed the high uptake in the skeletal tissue, the clearance in the blood was quick.

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Abstract  

The uptake of rare earth elements (REE) by Euglena gracilis cells has been investigated in Fudan University. The remarkable ability to transport REEs to these cell’s compartments had been observed. X-ray absorption fine structure experiments (XAFS) of cerium in Euglena gracilis were performed at Beijing Synchrotron Radiation Facility (BSRF) to directly determine the cerium valence state and coordination structure in situ. Extended X-ray absorption fine structure (EXAFS) derived calculation showed that cerium was surrounded by 8 N atoms with bond length of 0.258 nm. Combining with other measurements, it may indicate that most likely REEs are mainly located in chlorophyll molecules.

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Three isoforms of metallothionein protein induced with Zinc were isolated and purified from housefly larvae, Musca domestica, by gel filtration on Sephadex G-75, G-25 and anion exchange on DEAE-52 chromatography. Among them, one was found to possess antibacterial activity, and was further characterized by SDS-polyacrylamide gel electrophoresis, sulphydryl group determination, enzyme hydrolysis, and spectra property. Our results showed that the novel protein has the characteristics of heat-stable, low-molecular weight (6 kDa), rich-cysteine (approximately 12 cysteine residues in one molecule), metal affinity, and antibacterial activity. This paper was the first to report that metallothionein had antibacterial activity. We expect that this characteristic would give some help to investigate definite physiological functions of metallothionein.

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