Tea Consumption is Associated with Increased Risk of Kidney Stones in Northern Chinese: A Cross-sectional Study.

Kidney stones are a common urinary system condition that can progress to kidney disease. Previous studies on the association between tea consumption and kidney stones are inconsistent. A cross-sectional study to investigate the association between tea consumption and kidney stones was conducted from 2013 to 2014 and recruited 9,078 northern Chinese adults. A total of 8,807 participants were included in the final analysis. Participants' prevalence of kidney stones was 1.07%, 1.73%, and 2.25% based on their tea consumption frequency of never, occasionally, and often groups, respectively. Compared with the 'never' group, the odds ratios (95% confidence intervals) for the occurrence of kidney stones were 1.57 (1.00-2.46) and 1.65 (1.06-2.57) in the 'occasionally' and 'often' groups, respectively. After adjusting for sex, age, and other potential confounding factors, tea consumption still significantly increased the risk of kidney stones. Tea consumption is independently associated with an increased risk of kidney stones in the investigated population, suggesting that a decrease in the consumption of tea may be a preventive strategy for kidney stones.

[Inhibition of sulfite oxidation catalyzed by heavy metals in dual alkali flue gas desulfurization slurry].

Heavy metals accumulated in slurry of dual alkali flue gas desulfurization (FGD) present a significant catalysis to SO3(2-) oxidation, resulting in a waste of effective components for desulfurization. Na2S was adopted to precipitate heavy metal ions in FGD slurry, and the oxidation rate of SO3(2-) was obtained under different concentrations of heavy metal ions, to reveal the inhibition effect of Na2S on SO3(2-) oxidation catalyzed by heavy metal ions. Mn2+ showed a remarkable catalysis to SO3(-2) oxidation, as the initial oxidation rate of SO3(2-) was tripled to 0.65 mmol/(L x min) by adding 1.0 mmol/L Mn2+ into the slurry. SO3(2-) was catalytically oxidized rapidly with the reaction order 0.169 of Mn2+ within first 60 minutes, so it is of great importance to control the concentration of Mn2+ to inhibit SO3(2-) oxidation. At initial pH value of 6.50-8.50, Na2S removed heavy metal ions effectively from FGD slurry. Higher pH value favored the removal of heavy metal ions. The removal efficiencies of Mn2+, Zn2+, Ni2+ and Cd2+ were 91.0%, 88.1%, 85.5%, and above 99.9% respectively under the conditions of initial pH value 8.50 and Na2S dosage 240.0 mg/L. Mn2+ could be used as an indicator for the concentration of the heavy metal ions in the slurry. As the Mn2+ concentration decreased from 1.0 mmol/L to 5.0 x 10(-3) mmol/L by adding Na2S, the initial oxidation rate of SO3(2-) decreased by 64.6% to 0.23 mmol/(L x min). The desulfurization efficiencies increase 3.8%-5.1% by adding Na2S in a pilot scale setup. It comes to conclusion that heavy metal ions precipitation by adding Na2S with an indicator of Mn2+ to inhibit catalytic oxidation of SO3(2-) is feasible to reduce the consumption of desulfurizer in FGD slurry.

[Detection of BK virus infection in renal transplant recipients and clinical application].

OBJECTIVE: To study the detection methods of BK virus infection in kidney transplant recipients, and to explore the clinical application. METHODS: 132 cases of renal transplant recipients were undertaken BK virus detection including presence of decoy cells in urinary sediment, urine and serum BKV-DNA to demonstrate the BK virus replication. RESULT: Among 132 cases of renal transplant recipients, urinary decoy cell was found in 37 (28.0%) patients and the median time was 12 months after surgery. 32 (24.2%) patients were diagnosed as BK viruria at a median of 11 months after surgery, and 16 (12.1%) recipients were diagnosed as BK viremia at a median of 15 months after surgery, 5 patients with BK viruria were diagnosed as BK virus associated nephropathy according to allograft biopsy. CONCLUSION: To make early diagnosis of BK virus infection, detection of urine decoy cells and BKV-DNA in urine and plasma sample is important,which provides an important basis for the prevention of BK virus associated nephropathy.

[Mechanism and kinetic of methyldopa removal by Fenton's reagent].

Methyldopa was selected to be degraded by Fenton's reagent in the experiment. The experimental results showed that it was feasible to the removal of Methyldopa and COD by Fenton's reagent. The mechanism of Methyldopa removal by Fenton's reagent was significantly different according to the Fe2+ :H2O2 ratio. With high ratio of Fe2+ :H2O2 (> or = 2), the Fenton reaction was coagulation enhanced by H2O2. With medium ratio of Fe2+ :H2O2 (= 1), the Fenton reaction could be characterized into two specific systems : oxidation and coagulation. With low ratio of Fe2+ :H2O2 (< or = 0.2), the Fenton reaction was oxidation, including H2O2 oxidation catalyzed by Fe2+ and degradation by a hydrated ferryl-complex Fe(aq)4+. With the analysis of the mechanism according to low ratio of Fe2+ :H2O2 (< or = 0.2), a kinetics model was adopted to describe the reaction, and the rate equation could provide the evidence for the main reaction pathway, which was fitted very well with the experiment data for the relative error below 10%. It was showed that the kinetic models could primary describe the process of the removal of Methyldopa and COD by Fenton's reagent.

Application of chitosan as flocculant for coprecipitation of Mn(II) and suspended solids from dual-alkali FGD regenerating process.

Heavy metals and suspended solid (SS) needed to be removed from the recirculation of dual-alkali flue gas desulfurization (FGD) system. The feasibility of coprecipitation of heavy metal and SS by water-soluble chitosan was studied in a lab scale experiment. The association between chitosan and metal ions was verified through DSC and FT-IR. The pH investigation revealed that at the pH ranged from 5 to 9, there were three stages for different actions: adsorption of chitosan for Mn(II), precipitation of manganese hydroxide and coprecipitation of manganese hydroxide and chitosan-Mn(II) complex. The ion selectivity experiments showed that the occurrence of Ca(II) in the solution had little influence on the adsorption of chitosan for Mn(II). The decrease rate of adsorption capacity was about 0.0023 mmol g(-1) per 1 mg L(-1) Ca(II). When adsorption and flocculation of chitosan occurred at the same time and at the sufficient addition of chitosan, chitosan not only made solids flocculate but also enhanced sorption capacity of chitosan. Application of chitosan for coprecipitation of Mn(II) and SS could remove Mn(II) efficiently and improve the settling characteristics of SS from dual-alkali FGD regenerating process.

Oxidation inhibition of sulfite in dual alkali flue gas desulfurization system.

A laboratory-scale well-mixed thermostatic reactor with continuously blasting air was used to investigate the oxidation inhibition of sulfite in dual alkali flue gas desulfurization (FGD) system. The effects of operating parameters such as pH value and catalyst concentration on the oxidation were studied. Sodium thiosulfate was used in the system, and was found that it significantly inhabited the sulfite oxidation. In the absence of catalyst, sodium thiosulfate at 12.67 mmol/L had an inhibition efficiency of approximately 98%. While in the presence of catalyst, sodium thiosulfate at 26.72 mmol/L had an inhibition efficiency less than 85.0%. The oxidation reaction order of sulfite in the sodium thiosulfate was determined to be -1.90 and -0.55 in the absence and presence of the catalyst, respectively. Apparent activation energy of oxidation inhibition was calculated to be 53.9 kJ/mol. Pilot tests showed that the consumption rate of thiosulfate agreed well with the laboratory-scale experimental results.

Characterization of metal doped-titanium dioxide and behaviors on photocatalytic oxidation of nitrogen oxides.

A series of nanosized ion-doped TiO2 catalysts with different ion content (between 0.1 at .% and 1.0 at .%) have been prepared by wet impregnation method and investigated with respect to their behavior for UV photocatalytic oxidation of nitric oxide. The catalytic activity was correlated with structural, electronic and surface examinations of the catalysts using X-ray diffraction analysis (XRD), ultraviolet-visible (UV-Vis) absorption spectroscopy, transmission electron microscopy (TEM), energy disperse spectrometer (EDS) and high resolution-transmission electron microscopy (HR-TEM) techniques. An enhancement of the photocatalytic activity was observed for Zn2+ doping catalyst ranged from 0.1 at .% to 1.0 at .% which was attributed to the lengthened lifetime of electrons and holes. The improvement in photocatalytic activity could be also observed with the low doping concentration of Cr3+ (0.1 at .%). However, the doping of Fe3+, Mo6+, Mn2+ and the high doping concentration of Cr3+ had no contribution to photocatalytic activity of nitric oxide.

Enhanced degradation of carbon tetrachloride by surfactant-modified zero-valent iron.

Sorption of carbon tetrachloride (CT) by zero-valent iron (ZVI) is the rate-limiting step in the degradation of CT, so the sorption capacity of ZVI is of great importance. This experiment was aimed at enhancing the sorption of CT by ZVI and the degradation rate of CT by modification of surfactants. This study showed that ZVI modified by cationic surfactants has favorable synergistic effect on the degradation of CT. The CT degradation rate of ZVI modified by cetyl pyridinium bromide (CPB) was higher than that of the unmodified ZVI by 130%, and the CT degradation rate of ZVI modified by cetyl trimethyl ammonium bromide (CTAB) was higher than that of the unmodified ZVI by 81%. This study also showed that the best degradation effect is obtained at the near critical micelle concentrations (CMC) and that high loaded cationic surfactant does not have good synergistic effect on the degradation due to its hydrophilicity and the block in surface reduction sites. Furthermore degradation of CT by ZVI modified by nonionic surfactant has not positive effect on the degradation as the ionic surfactant and the ZVI modified by anionic surfactant has hardly any obvious effects on the degradation.

Modification of FGD gypsum in hydrothermal mixed salt solution.

A novel utilization way of the sludge from wet calcium-based flue gas desulfurization (FGD) processes has been developed in this paper. This study focused on the conversion of the FGD gypsum into alpha-hemihydrate calcium sulfate by a hydrothermal salt solution method at atmospheric pressure. Experimental study has been carried out in a batch reactor. Qualitative and quantitative analyses were made by DSC/TG thermal analysis, SEM, XRD, metalloscope and chemical analysis. The experimental results showed that the modification of FGD gypsum was controlled by the dissolution and recrystallization mechanisms. With the introduction of FGD gypsum the salt solution was supersaturated, then crystal nucleus of alpha-hemihydrate calcium sulfate were produced in the solution. With the submicroscopic structure of FGD gypsum crystal changed, the crystal nucleus grew up into alpha-hemihydrate calcium sulfate crystals. Thus, the modification of FGD gypsum was fulfilled.

[Efficacy and safety of different dosages of intravesical epirubicin instillation for prevention of primary superficial bladder carcinoma from recurrence].

OBJECTIVE: To investigate the efficiency and safety of different regimens by intravesical instillation of epirubicin, a derivative of adriamycin, for the prevention of primary superficial bladder carcinoma from recurrence. METHODS: Ninety patients supplemented with intravesical epirubicin instillation after operation were randomly divided into three groups: Group A--80 mg in one dose; Group B--repeated epirubicin 40 mg q wk x 4-8 sessions followed by q month to the end of the second year; or Group C--50 mg q month to the same duration. All patients were followed up for two years by observing the recurrence rates and side effects. RESULTS: The recurrence rate of groups A, B and C at one year was 16.7%, 13.3% and 16.7%, respectively, without any significant difference observed. However, it was 50.0%, 36.7% and 36.7% at two years, at which time the recurrence rate of group A was significantly higher than those of groups B and C. The side effects rate was 23.3%, 40.0% and 33.3% for groups A, B and C, respectively. The more instillations the patients had, the more severe side effects were. CONCLUSION: Early postoperative single high dose intravesical instillation of epirubicin combined with repeated lower doses of the same drug every month may be an efficient and safe regimen to prevent the primary superficial bladder carcinoma from recurrence.

Kinetics of aerobically activated sludge on terylene artificial silk printing and dyeing wastewater treatment.

Aerobically activated sludge processing was carried out to treat terylene artificial silk printing and dyeing wastewater (TPD wastewater) in a lab-scale experiment, focusing on the kinetics of the COD removal. The kinetics parameters determined from experiment were applied to evaluate the biological treatability of wastewater. Experiments showed that COD removal could be divided into two stages, in which the ratio BOD/COD (B/C) was the key factor for stage division. At the rapid-removal stage with B/C>0.1, COD removal could be described by a zero order reaction. At the moderate-removal stage with B/C<0.1, COD removal could be described by a first order reaction. Then Monod equation was introduced to indicate COD removal. The reaction rate constant (K) and half saturation constant (K(S)) were 0.0208-0.0642 L/(gMLSS).h and 0.44-0.59 (gCOD)/L respectively at 20 degrees C-35 degrees C. Activation energy (E(a)) was 6.05 x 10(4) J/mol. By comparison of kinetic parameters, the biological treatability of TPD wastewater was superior to that of traditional textile wastewater. But COD removal from TPD-wastewater was much more difficult than that from domestic and industrial wastewater, such as papermaking, beer, phenol wastewater, etc. The expected effluent quality strongly related to un-biodegradable COD and kinetics rather than total COD. The results provide useful basis for further scaling up and efficient operation of TPD wastewater treatment.

Catalytic oxidation of calcium sulfite in solution/aqueous slurry.

Forced oxidation of calcium sulfite aqueous slurry is a key step for the calcium-based flue gas desulfurization (FGD) residue. Experiments were conducted in a semi-batch system and a continuous flow system on lab scales. The main reactor in semi-batch system is a 1000 ml volume flask. It has five necks for continuous feeding of gas and a batch of calcium sulfite solution/aqueous slurry. In continuous flow system, the main part is a jacketed Pyrex glass reactor in which gas and solution/aqueous slurry are fed continuously. Calcium sulfite oxidation is a series of complex free-radical reactions. According to experimental results and literature data, the reactions are influenced significantly by manganese as catalyst. At low concentration of manganese and calcium sulfite, the reaction rate is dependent on 1.5 order of sulfite concentration, 0.5 order of manganese concentration, and zero order of oxygen concentration in which the oxidation is controlled by chemical kinetics. With concentrations of calcium sulfite and manganese increasing, the reactions are independent gradually on the constituents in solution but are impacted by oxygen concentration. Manganese can accelerate the free-radical reactions, and then enhances the mass transfer of oxygen from gas to liquid. The critical concentration of calcium sulfite is 0.007 mol/L, manganese is 10(-4) nol/L, and oxygen is of 0.2-0.4 atm.

Biodegradability of terephthalic acid in terylene artificial silk printing and dyeing wastewater.

As the characteristic pollutant, terephthalic acid (TA) was in charge of 40%-78% of the total COD of terylene artificial silk printing and dyeing wastewater (TPW-water). The studies on biodegradability of TA were conducted in a serial of activated sludge reactors with TPW-water. TA appeared to be readily biodegradable with removal efficiency over 96.5% under aerobic conditions, hardly biodegradable with removal efficiency below 10% under anoxic conditions and slowly biodegradable with a turnover between 31.4% and 56.0% under anaerobic conditions. TA also accounted for the majority of BOD in TPW-water. The process combined by anoxic, anaerobic and aerobic activated sludge reactor was suitable for TA degradation and TPW-water treatment, Further, the aerobic process was essentially much more effective than the anaerobic or anoxic one to degrade TA in TPW-water.