Semiconductor photocatalysis can be operated over a narrow pH range for wastewater treatment. In this study, a simulated solar-light-mediated bismuth tungstate (SSL/Bi2WO6) process is found to be effective for norflox...Semiconductor photocatalysis can be operated over a narrow pH range for wastewater treatment. In this study, a simulated solar-light-mediated bismuth tungstate (SSL/Bi2WO6) process is found to be effective for norfloxacin degradation over a narrow pH range. To broaden the operating pH range of the SSL/Bi2WO6 process, an NH4+ buffer system and an Fe3+ salt were introduced under extremely basic and acidic pH conditions, respectively. The NH4+ buffer system continuously supplied hydroxyl ions to generate ·OH radicals and prevented acidification of the solution, resulting in improved norfloxacin removal and mineralization removal under alkaline conditions. In contrast, the Fe3+ salt offered an additional homogeneous photo-sensitization pathway. The former treatment assisted in norfloxacin decay and the latter increased the collision frequency between the photo-generated hole and hydroxyl ions. Moreover, the effect of parameters such as pH and Fe3+ dosage was optimized.展开更多
AIM:To investigate whether potent acid inhibition is effective in non-erosive reflux disease (NERD) refractory to standard rabeprazole (RPZ) treatment. METHODS:We treated 10 Japanese patients with NERD resistant to st...AIM:To investigate whether potent acid inhibition is effective in non-erosive reflux disease (NERD) refractory to standard rabeprazole (RPZ) treatment. METHODS:We treated 10 Japanese patients with NERD resistant to standard dosages of RPZ:10 mg or 20 mg od,20 mg bid,or 10 mg qid for 14 d. All patients completed a frequency scale for symptoms of gastroesophageal reflux disease questionnaire frequency scale for the symptoms of GERD (FSSG); and underwent 24 h pH monitoring on day 14. RESULTS:With increased dosages and frequency of administration of RPZ,median intragastric pH significantly increased,and FSSG scores significantly decreased. With RPZ 10 mg qid,potent acid inhibition was attained throughout 24 h. However,five subjects were refractory to RPZ 10 mg qid,although the median intragastric pH in these subjects (6.6,range:6.2-7.1) was similar to that in the remaining five responsive subjects (6.5,range:5.3-7.3). With baseline RPZ 10 mg od,FSSG scores in responsive patients improved by > 30%,whereas there was no significant decrease in the resistant group. CONCLUSION:NERD patients whose FSSG score fails to decrease by > 30% after treatment with RPZ 10 mg od for 14 d are refractory to higher dosage.展开更多
The acidity characteristics of acid sulphate soils of Kuttanad, Kerala, were studied in detail by collecting surface, profile and subsurface soil samples from 20 locations of six soil series viz., Ambalapuzha, Purakka...The acidity characteristics of acid sulphate soils of Kuttanad, Kerala, were studied in detail by collecting surface, profile and subsurface soil samples from 20 locations of six soil series viz., Ambalapuzha, Purakkad, Thotapally, Thuravur, Kallara and - Thakazhi that belonged to acid sulphate soils. The soils were extremely acidic showing a range of pH （H：O） varying from 2.5 to 5.2. Lowest pH was recorded by Thakazhi series and the highest by Thotapally. The potential acidity of soils ranged from 14.71 cmol.kg-1 to 110.5 cmol-kg1 with Thakazhi series showing the highest value. The contribution of hydrolytic acidity to potential acidity ranged from 70.2% to 97.2%. In all soil series, exchangeable A13＋ was greater than exchangeable H~. A significant correlation was observed among pH （KCI）, pH （H20） and pH （CaCI2） in all series.展开更多
基金supported by the National Science Foundation of China(41877481,41503102)the open project of the State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,Chinese Academy of Science(SKLLQG1729)+2 种基金the China Postdoctoral Science Foundation(2018M643669)the Fundamental Research Funds for the Central Universities(2018249)the "Hundred Talent Program" of the Chinese Academy of Sciences~~
文摘Semiconductor photocatalysis can be operated over a narrow pH range for wastewater treatment. In this study, a simulated solar-light-mediated bismuth tungstate (SSL/Bi2WO6) process is found to be effective for norfloxacin degradation over a narrow pH range. To broaden the operating pH range of the SSL/Bi2WO6 process, an NH4+ buffer system and an Fe3+ salt were introduced under extremely basic and acidic pH conditions, respectively. The NH4+ buffer system continuously supplied hydroxyl ions to generate ·OH radicals and prevented acidification of the solution, resulting in improved norfloxacin removal and mineralization removal under alkaline conditions. In contrast, the Fe3+ salt offered an additional homogeneous photo-sensitization pathway. The former treatment assisted in norfloxacin decay and the latter increased the collision frequency between the photo-generated hole and hydroxyl ions. Moreover, the effect of parameters such as pH and Fe3+ dosage was optimized.
基金Supported by a Grant-in-Aid from the Japanese Ministry of Education, Culture, Sports, Science and Technology (22790640)
文摘AIM:To investigate whether potent acid inhibition is effective in non-erosive reflux disease (NERD) refractory to standard rabeprazole (RPZ) treatment. METHODS:We treated 10 Japanese patients with NERD resistant to standard dosages of RPZ:10 mg or 20 mg od,20 mg bid,or 10 mg qid for 14 d. All patients completed a frequency scale for symptoms of gastroesophageal reflux disease questionnaire frequency scale for the symptoms of GERD (FSSG); and underwent 24 h pH monitoring on day 14. RESULTS:With increased dosages and frequency of administration of RPZ,median intragastric pH significantly increased,and FSSG scores significantly decreased. With RPZ 10 mg qid,potent acid inhibition was attained throughout 24 h. However,five subjects were refractory to RPZ 10 mg qid,although the median intragastric pH in these subjects (6.6,range:6.2-7.1) was similar to that in the remaining five responsive subjects (6.5,range:5.3-7.3). With baseline RPZ 10 mg od,FSSG scores in responsive patients improved by > 30%,whereas there was no significant decrease in the resistant group. CONCLUSION:NERD patients whose FSSG score fails to decrease by > 30% after treatment with RPZ 10 mg od for 14 d are refractory to higher dosage.
文摘The acidity characteristics of acid sulphate soils of Kuttanad, Kerala, were studied in detail by collecting surface, profile and subsurface soil samples from 20 locations of six soil series viz., Ambalapuzha, Purakkad, Thotapally, Thuravur, Kallara and - Thakazhi that belonged to acid sulphate soils. The soils were extremely acidic showing a range of pH （H：O） varying from 2.5 to 5.2. Lowest pH was recorded by Thakazhi series and the highest by Thotapally. The potential acidity of soils ranged from 14.71 cmol.kg-1 to 110.5 cmol-kg1 with Thakazhi series showing the highest value. The contribution of hydrolytic acidity to potential acidity ranged from 70.2% to 97.2%. In all soil series, exchangeable A13＋ was greater than exchangeable H~. A significant correlation was observed among pH （KCI）, pH （H20） and pH （CaCI2） in all series.
