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  • Author or Editor: Zhang Lei x
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Abstract  

This paper discusses a novel application of PIGE for the determination of13C in breath. Samples of human breath, urea, glucose, benzamide, barium carbonate were analyzed against cylinder CO2 and graphite standard. An accuracy check of the13C determination (with reference to mass spectrometric True results) gave a relative error of only –0.4% for PIGE. The performance of different standards in this determination was assessed. Relative standard deviation for the determination of13C isotopic abundance in breath samples were <20%. Then, if a 25% change is conservatively assumed observable in13C abundance, an increase in13C percent isotopic abundance from the natural 1.11% (average) to only 1.39% may be detected.

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Abstract

Primary giant cell tumor of soft tissue (GCT-ST) is a low-grade malignant tumor and uncommon cancer originating from soft tissue. Primary hepatic GCT is an extremely rare finding. Only a handful of cases have been reported in the literature. Although GCT-ST has a relatively low malignant potential tumor in the view of histology, some patients who suffered from this tumor have poor prognosis after surgery because of the aggressiveness. Thus, the early diagnosis is important, and a preoperative imaging can supply the evidence of differential diagnosis to evaluate tumor malignancy. In this study, we systematically present a rare case of 56-year-old women with chills, fever, jaundice and anorexia for 3 days. CT showed a huge and multinodular confluent lesion in the left lobe of the liver, and it had a calcification component. This tumor is characterized by fibrous components and calcification, which showed iso-intense with peripheral hypo-intense on T1WI, and mainly inhomogeneous hypo-intense on fat-suppressed T2WI. Moreover, it was mainly hypointense and peripheral linear hyperintense on DWI images with a b-value of 800 (b800) and iso-hyperintense on ADC.

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Abstract  

In this work, adsorption of Ni(II) from aqueous solution onto hematite under various solution chemistry and temperature was investigated. The results indicated that the pseudo-second-order rate equation fitted the kinetic adsorption well. The adsorption of Ni(II) onto hematite was strongly dependent on pH and ionic strength. At low pH, the adsorption was dominated by outer-sphere surface complexation or ion exchange, whereas inner-sphere surface complexation was the main adsorption mechanism at high pH. A positive effect of FA on Ni(II) adsorption was found at pH < 8.0, whereas a negative effect was observed at pH > 8.0. The Langmuir, Freundlich, and D–R models were applied to simulate the adsorption isotherms at three different temperatures of 293.15, 313.15 and 333.15 K. The thermodynamic parameters were calculated from the temperature dependent adsorption, and the results indicated that the adsorption was endothermic and spontaneous.

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Abstract  

The sorption of 63Ni(II) from aqueous solution using ZSM-5 zeolite was investigated by batch technique under ambient conditions. ZSM-5 zeolite was characterized by point of zero net proton charge (PZNPC) titration. The sorption was investigated as a function of shaking time, pH, ionic strength, foreign ions, humic acid (HA), fulvic acid (FA) and temperature. The results indicate that the sorption of 63Ni(II) on ZSM-5 zeolite is strongly dependent on pH. The sorption is dependent on ionic strength at low pH, but independent of ionic strength at high pH values. The presence of HA/FA enhances 63Ni(II) sorption at low pH values, whereas reduces 63Ni(II) sorption at high pH values. The sorption isotherms are simulated by Langmuir model very well. The thermodynamic parameters (i.e., ∆H 0, ∆S 0 and ∆G 0) for the sorption of 63Ni(II) are determined from the temperature dependent sorption isotherms at 293.15, 313.15 and 333.15 K, respectively, and the results indicate that the sorption process of 63Ni(II) on ZSM-5 zeolite is spontaneous and endothermic.

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Abstract  

The sorption of 60Co(II) on γ-Al2O3 was conducted under various conditions, i.e., contact time, adsorbent content, pH, ionic strength, foreign ions, humic acid (HA), and temperature. Results of sorption data analysis indicated that the sorption of 60Co(II) on γ-Al2O3 was strongly dependent on pH and ionic strength. At low pH the sorption was dominated by outer-sphere surface complexation or ion exchange, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The presence of different cation ions influenced 60Co(II) sorption, while the presence of different anion ions had no obvious influences on 60Co(II) sorption. The presence of HA decreased the sorption of 60Co(II) on γ-Al2O3. The sorption isotherms were simulated well with the Langmuir model. The thermodynamic parameters (ΔH 0 , ΔS 0 and ΔG 0 ) calculated from the temperature-dependent sorption isotherms indicated that the sorption of 60Co(II) on γ-Al2O3 was an endothermic and spontaneous process. Experimental results indicated that the low cost material was a suitable material in the preconcentration of 60Co(II) from large volumes of aqueous solutions.

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Abstract  

The sorption of Co(II) from aqueous solution on Na-rectorite was investigated under ambient conditions. Experiments were carried out as a function of contact time, solid content, pH, ionic strength, foreign ions, fulvic acid and temperature. The results indicated that the sorption of Co(II) was strongly dependent on pH. At low pH the sorption was dominated by outer-sphere surface complexation or ion exchange, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The Langmuir, Freundlich and Dubinin–Radushkevich (D–R) models were used to simulate the sorption isotherms at three different temperatures. The thermodynamic data (∆G 0, ∆S 0, ∆H 0) were calculated from the temperature dependent sorption isotherms and the results suggested that the sorption process of Co(II) on Na-rectorite was spontaneous and endothermic. Experimental results indicate that Na-rectorite is a suitable adsorbent for preconcentration and solidification of Co(II) from large volumes of aqueous solutions.

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Microcystis colonial size and concentration have detrimental effects on life history traits of Daphnia, but their detailed interactions have remained unclear so far. Our experiments show that the interaction between Microcystis colonial size and concentration on maturation time, life expectancy, net reproductive rate and innate capacity of increase in Daphnia similoides was significant. In all groups, the survival rate of D. similoides was 100% within 8 days. This value then declined quickly in the large-colony groups and in the SH group of Microcystis. Colonial M. aeruginosa significantly reduced the maturation time and body length at maturity of D. similoides. The number of offspring at first reproduction per female in the SH group of Microcystis was significantly higher than those in other groups. Net reproductive rate of D. similoides in the SL group of Microcystis was significantly higher than those in other groups of Microcystis. The innate capacity of increase of D. similoides in small-colony Microcystis groups was significantly higher than that in the large-colony groups. The results suggested that the effect of smallcolony Microcystis on the reproduction of Daphnia was positive under lower concentration, while their toxicity was intensitied under higher concentration when small-colony Microcystis were by Daphnia as food.

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Abstract  

Bentonite was investigated to remove Ni(II) from aqueous solutions because of its strong sorption ability. Herein, bentonite was modified with sodium carboxymethylcellulose (CMC) and used as an adsorbent to remove Ni(II) from aqueous solutions. The results indicated that CMC-bentonite had higher sorption capacity than bare bentonite in the sorption of Ni(II) from aqueous solutions. Sorption of Ni(II) on CMC-bentonite was mainly dominated by ion exchange or outer-sphere surface complexation at low pH values, but by inner-sphere surface complexation or surface precipitation at high pH values. The thermodynamic data calculated from temperature dependent sorption isotherms indicated that the sorption of Ni(II) to CMC-bentonite hybrids was an spontaneous process and enhanced with increasing temperature.

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Abstract  

The sorption of Cd(II) from aqueous solution on γ-Al2O3 was investigated under ambient conditions. Experiments were carried out as a function of contact time, solid content, pH, ionic strength, foreign ions, fulvic acid and temperature. The results indicated that the sorption of Cd(II) was strongly dependent on pH and ionic strength. At low pH, the sorption of Cd(II) was dominated by outer-sphere surface complexation and ion exchange with Na+/H+ on γ-Al2O3 surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The Langmuir, Freundlich and Dubinin–Radushkevich (D–R) models were used to simulate the sorption isotherms at three different temperatures. The thermodynamic data (ΔG 0, ΔS 0, ΔH 0) calculated from the temperature dependent sorption isotherms suggested that the sorption of Cd(II) on γ-Al2O3 was an spontaneous and endothermic process.

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Abstract  

Uranyl luminescences in phosphoric acid system has been studied. Uranyl excited by a nitrogen laser shows single or biexponential luminescence decays in the phosphoric acid system. When the uranyl ion or phosphoric acid concentration are lower, a single exponential luminescence decay appears, whereas at higher uranyl ion or phosphoric acid concentrations, biexponential decay is observed. Time-resolved spectra of uranyl in this system are measured. The reasons of the phenomena are tentatively established.

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