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酸化离子电位水用于妇科术前阴道冲洗的效果观察 被引量:2
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作者 宋亚丽 杜文辉 +1 位作者 杨淑宁 孙春雁 《辽宁医学杂志》 2002年第1期55-56,共2页
酸化离子电位水(EOW)是将自来水加入少量的氯化钠于电解水生成器中产生的液体消毒剂.因其杀菌性能好,成本低廉,使用方便,已开始引起人们的关注[1,2].本研究将EOW用于妇科肿瘤住院患者术前的阴道冲洗,并以新洁尔灭作为对照,观察其对阴道... 酸化离子电位水(EOW)是将自来水加入少量的氯化钠于电解水生成器中产生的液体消毒剂.因其杀菌性能好,成本低廉,使用方便,已开始引起人们的关注[1,2].本研究将EOW用于妇科肿瘤住院患者术前的阴道冲洗,并以新洁尔灭作为对照,观察其对阴道清洁度和支原体的影响.现报告如下. 展开更多
关键词 妇科手术 术前冲洗 酸化离子电位水
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酸化离子水配制吡嗪酰胺药敏培养基的研究
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作者 胡云岚 程冬娥 申建维 《国际检验医学杂志》 CAS 2011年第7期785-786,共2页
目的探讨满足吡嗪酰胺活性需要的同时,研制使结核菌生长良好的吡嗪酰胺(PZA)药敏培养基。方法以改良罗氏培养基为基础,加大镁离子浓度,去掉马铃薯淀粉,用pH值2.34、氧化还原电位为1 174 mV的酸化离子水配制PZA药敏培养基。按《结核病诊... 目的探讨满足吡嗪酰胺活性需要的同时,研制使结核菌生长良好的吡嗪酰胺(PZA)药敏培养基。方法以改良罗氏培养基为基础,加大镁离子浓度,去掉马铃薯淀粉,用pH值2.34、氧化还原电位为1 174 mV的酸化离子水配制PZA药敏培养基。按《结核病诊断细菌学检验规程》,检测120株结核分枝杆菌对PZA的敏感性。结果门诊分离的60株分枝杆菌,PZA耐药率为13.3%,该院患者和深圳市慢性病医院分离的15株完全耐药的分枝杆菌,在此培养基上对PZA呈耐药性。结论此培养基配制简单,可与其他药敏试验同步进行,易于推广应用。 展开更多
关键词 呲嗪酰胺 培养基 分枝杆菌 非典型性 酸化离子
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酸化离子水配制吡嗪酰胺药敏培养基
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作者 程冬娥 黄乔蓉 《结核病临床与控制》 2002年第1期7-9,共3页
目的:探讨满足吡嗪酰胺活性需要的同时,研制使结核菌生长良好的PZA药敏培养基。方法:以改良罗氏培养基为基础,加大镁离子浓度,去掉马铃薯淀粉,用PH2.34,氧化还原电位为1174mv的酸化离子水配制PZA药敏培养基,按《结核病诊断细... 目的:探讨满足吡嗪酰胺活性需要的同时,研制使结核菌生长良好的PZA药敏培养基。方法:以改良罗氏培养基为基础,加大镁离子浓度,去掉马铃薯淀粉,用PH2.34,氧化还原电位为1174mv的酸化离子水配制PZA药敏培养基,按《结核病诊断细菌学检验规程》,测试了120株结核分杆菌对PZA的敏感性。结果:门诊分离的60株分支杆菌,PZA耐药率为13.3%,住院患者和深圳市慢性病医院分离15株完全耐药的分支杆菌,在此培养基上对PZA耐药。结论:此培养基配制简单,可与其他药敏试验同步进行,易于推广应用。 展开更多
关键词 酸化离子 吡嗪酰胺 培养基 结核杆菌 抗结核菌药
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酸化电位水用于妇科术前阴道冲洗的效果 被引量:10
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作者 宋亚丽 杨淑宁 +2 位作者 刘晓平 杜文辉 孙春雁 《中华医院感染学杂志》 CAS CSCD 2002年第3期206-206,208,共2页
目的 探讨酸化离子电位水 (EOW)冲洗阴道的清洁效果。方法 用 EOW冲洗阴道壁、穹隆部及宫颈 ,持续 2 min后取标本进行阴道清洁度、支原体检测 ,同时采用 0 .1%苯扎溴铵 (新洁尔灭 )冲洗作为对照。结果 EOW组 (40例 )经过 1次冲洗后... 目的 探讨酸化离子电位水 (EOW)冲洗阴道的清洁效果。方法 用 EOW冲洗阴道壁、穹隆部及宫颈 ,持续 2 min后取标本进行阴道清洁度、支原体检测 ,同时采用 0 .1%苯扎溴铵 (新洁尔灭 )冲洗作为对照。结果 EOW组 (40例 )经过 1次冲洗后阴道清洁度由 ~ 度 (35例 )转为 度者 16例 ,占 4 5 .71% ,经过 3次冲洗后阴道清洁度转 度者为 2 8例 ,占 80 % ;支原体感染 2 2例 ,经过 3次冲洗后 ,转阴 12例 ,转阴率为 5 4 .5 % ;EOW的清洁阴道作用和支原体转阴率均明显优于苯扎溴铵组 (P<0 .0 1)。结论 EOW是用于妇科手术前阴道冲洗的有效消毒剂 ,其消毒效果明显优于苯扎溴铵 ,EOW对皮肤、粘膜无刺激 ,对环境无污染 ,制作方便。 展开更多
关键词 酸化离子电位水 阴道冲洗 阴道清洁度 解脲支原体
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Self-repairing Al_(2)O_(3)-TiO_(2)coatings fabricated through plasma electrolytic oxidation with various cathodic pulse parameters
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作者 Mehri HASHEMZADEH Keyvan RAEISSI +4 位作者 Fakhreddin ASHRAFIZADEH Frank SIMCHEN Amin HAKIMIZAD Monica SANTAMARIA Thomas LAMPKE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3326-3343,共18页
The influence of cathodic pulse parameters was evaluated on plasma electrolytic oxidation(PEO)coatings grown on 7075 aluminum alloy in a silicate-based electrolyte containing potassium titanyl oxalate(PTO)using pulsed... The influence of cathodic pulse parameters was evaluated on plasma electrolytic oxidation(PEO)coatings grown on 7075 aluminum alloy in a silicate-based electrolyte containing potassium titanyl oxalate(PTO)using pulsed bipolar waveforms with various cathodic duty cycles and cathodic current densities.The coatings were characterized by SEM,EDS,and XRD.EIS was applied to investigate the electrochemical properties.It was observed that the increase of cathodic duty cycle and cathodic current density from 20%and 6 A/dm^(2) to 40%and 12 A/dm^(2) enhances the growth rate of the inner layer from 0.22 to 0.75μm/min.Adding PTO into the bath showed a fortifying effect on influence of the cathodic pulse and the mentioned change of cathodic pulse parameters,resulting in an increase of the inner layer growth rate from 0.25 to 1.10μm/min.Based on EDS analysis,Si and Ti were incorporated dominantly in the upper parts of the coatings.XRD technique merely detectedγ-Al_(2)O_(3),and there were no detectable peaks related to Ti and Si compounds.However,the EIS results confirmed that the incorporation of Ti^(4+)into alumina changed the electronic properties of the coating.The coatings obtained from the bath containing PTO using the bipolar waveforms with a cathodic duty cycle of 40%and current density values higher than 6 A/dm^(2) showed highly appropriate electrochemical behavior during 240 d of immersion due to an efficient repairing mechanism.Regarding the effects of studied parameters on the coating properties,the roles of cathodic pulse parameters and PTO in the PEO process were highlighted. 展开更多
关键词 Al_(2)O_(3)-TiO_(2)coating plasma electrolytic oxidation potassium titanyl oxalate electrochemical impedance spectroscopy
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Influence of thermal history on conversion of aluminate species in sodium aluminate solution 被引量:5
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作者 李小斌 赵东峰 +3 位作者 杨帅帅 王丹琴 周秋生 刘桂华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3348-3355,共8页
It is necessary to clarify the influence of thermal history on the conversion of aluminate species in sodium aluminate solution in order to optimize Bayer alumina production. The interconversion of various solution sp... It is necessary to clarify the influence of thermal history on the conversion of aluminate species in sodium aluminate solution in order to optimize Bayer alumina production. The interconversion of various solution species in the systems was investigated by measuring the infrared spectra of sodium aluminate solution with different compositions after separate heat treatment, dilution and concentration. The results show that increasing temperature or prolonging holding time favors the transformation of Al2O(OH)2- to Al—OH vibration(condensed Al O4 tetrahedral aluminate ion) at about 880 cm-1 and Al(OH)-4. A12O(OH)2-66 and Al—OH tetrahedral dimer ions convert rapidly to Al(OH)-4 during the dilution process; however, the back transformation of Al(OH)-4 to the Al—OH tetrahedral dimer ions can occur in diluted sodium aluminate solution. As for the concentration process, the transformation of Al(OH)-4 to A12O(OH)2-6 and Al—OH tetrahedral dimer ions can take place, while it is relatively difficult to transform to A12O(OH)2-6. 展开更多
关键词 aluminate ions structural changes infrared spectrum thermal history
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Analysis of Soil Acidification Trend on the South Bank of Hongze Lake during Recent 30 Years 被引量:2
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作者 刘廷武 李聪 +4 位作者 赵伟男 杨用钊 张杰 徐建明 罗玉明 《Agricultural Science & Technology》 CAS 2015年第9期1955-1958,共4页
Based on soil monitoring data in nine sites of Jinhu, Xuyi and Hongze counties on the south bank of Hongze Lake from 1982 to 2013, changes in soil p H, total nitrogen(TN) content, available phosphorus content, organ... Based on soil monitoring data in nine sites of Jinhu, Xuyi and Hongze counties on the south bank of Hongze Lake from 1982 to 2013, changes in soil p H, total nitrogen(TN) content, available phosphorus content, organic matter(OM)content and cation exchange capacity(CEC) were analyzed. The results show that due to excessive application of chemical fertilizer in soil on the south bank of Hongze Lake, soil p H reduced by about 2 on average, while TN content and available phosphorus content in soil increased by more than one time and 2-5 times respectively. Soil acidification caused by agricultural production was very serious. In addition, low soil p H resulted in serious loss of soil cation, so that soil CEC in2013 accounted for less than 50% of that in 1982 and affected mineral nutrient metabolism of crops. Therefore, application of calcium, potassium and trace-element fertilizer should be paid more attention to during agricultural production in future. 展开更多
关键词 Hongze Lake Soil acidification Nitrogen and phosphorus content CATION
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Surface plasmon resonance-induced visible-light photocatalytic performance of silver/silver molybdate composites 被引量:5
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作者 杨祥龙 王尹 +3 位作者 徐骁 瞿阳 丁星 陈浩 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期260-269,共10页
Novel silver/silver molybdate(Ag/Ag2MoO4) composites with surface plasmon resonance(SPR)-enhanced photocatalytic performance were successfully fabricated via a facile one-pot hydrothermal route with the presence o... Novel silver/silver molybdate(Ag/Ag2MoO4) composites with surface plasmon resonance(SPR)-enhanced photocatalytic performance were successfully fabricated via a facile one-pot hydrothermal route with the presence of sodium dodecyl sulfate(SDS) in this study.The as prepared silver/silver molybdate(Ag/Ag2MoO4) composites were systematically characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and ultraviolet-visible diffuse reflectance absorption spectroscopy(DRS) in order to investigate their crystal structure,morphology and optical property as well.The photocatalytic activities of the composites were subsequently evaluated by their ability to degrade rhodamine B(RhB) under visible-light irradiation.Varies of controlled experiments were then carefully operated to gain a deep insight into the assembling of Ag/Ag2MoO4composites.It was found that preparation conditions such as pH,reaction time,and the amount of surfactant played important roles in the formation of composites with octahedral microstructures.And the composite obtained at 160 ℃ using 0.5 g of sodium dodecyl sulfate exhibited the highest photocatalytic performance under visible-light irradiation.Capture experiments were also conducted to clarify the function of different active species generated on the surface of Ag/Ag2MoO4during the photocatalytic process,in which both holes and ·OH radicals were found to play crucial role in photocatalytic removal of RhB under visible light irradiation.A possible photocatalytic mechanism of Ag/Ag2MoO4 was finally proposed on the basis of all the results to explain the higher photocatalytic activity of the octahedral Ag/Ag2MoO4 composites.It was inferred that the photoinduced "hot" electrons can quickly transfer from the Ag NPs to the conduction band of Ag2MoO4 and react with oxygen and H2O to generate a large quality of active radicals such as ·OH and ·O2^- because of the SPR effects.Besides,this SPR effects of Ag nanoparticles deposited on the surface of Ag2MoO4 can not only dramatically amplify its light absorption,especially in the visible region,but also promote the separation of photoexcited electron-hole pairs and effectively decrease electron-hole recombination. 展开更多
关键词 SILVER Silver molybdate Sodium dodecyl sulfate Photocatalytic activity Surface plasmon resonance Rhodamine B
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妇科手术
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《中国计划生育和妇产科》 2002年第6期353-355,共3页
关键词 妇科手术 阴道镜下多点活检 大卵巢囊肿 非脱垂子宫 新洁尔灭 全宫切除术 子宫全切术 腹腔镜手术 宫颈病变 酸化离子电位水
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Removal of vanadate anion by calcined Mg/Al-CO_3 layered double hydroxide in aqueous solution 被引量:3
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作者 宋海磊 焦飞鹏 +3 位作者 蒋新宇 于金刚 陈晓青 杜邵龙 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3337-3345,共9页
Mg/Al-CO3 layered double hydroxide (LDH2) with Mg(II):Al(III) molar ratio of 2:1 was synthesized by co-precipitation method and its calcined product Mg2Al-CLDH(CLDH2) was prepared by heating Mg2Al-LDH at 773... Mg/Al-CO3 layered double hydroxide (LDH2) with Mg(II):Al(III) molar ratio of 2:1 was synthesized by co-precipitation method and its calcined product Mg2Al-CLDH(CLDH2) was prepared by heating Mg2Al-LDH at 773 K for 6 h. Removal of vanadate anion ( 3-4VO ) from aqueous solution on CLDH2 was studied. Batch studies were carried out to address various experimental parameters such as Mg/Al molar ratio, adsorbent dosage, initial concentration of solution, contact time and temperature. Vanadate was removed effectively at the optimized experimental conditions. The adsorption kinetics data fitted the pseudo-first-order model. Isotherms for adsorption vanadate by CLDH2 at different solution temperatures were well described using the Langmuir and Freundlich equations, and the isotherm parameters were calculated using linear regression analysis. The adsorption data fitted the langmuir model with good values of the correlation coefficient (R2〉0.999). The negative value ofΔGΘand the positive value ofΔHΘindicate that the adsorption processes are spontaneous endothermic in nature. The mechanism of adsorption suggests that the surface adsorption is the main process. 展开更多
关键词 layered double hydroxide VANADATE adsorption KINETICS THERMODYNAMICS
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Determination of penehyclidine hydrochloride in beagle dog plasma by liquid chromatography-electrospray ionization mass spectrometry and the pharmacokinetic study
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作者 崔彦 尹海林 +3 位作者 包旭 熊梅瑾 陈聪 叶利明 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第2期122-128,共7页
To develop a fast and sensitive liquid chromatography-mass spectrometry method for the determination of penehyclidine hydrochloride (PH) in beagle dog plasma. PH and diphenhydramine hydrochloride (internal standard... To develop a fast and sensitive liquid chromatography-mass spectrometry method for the determination of penehyclidine hydrochloride (PH) in beagle dog plasma. PH and diphenhydramine hydrochloride (internal standard, IS) were extracted with a solvent mixture of petroleum ether-ethyl ether (7:3). Chromatographic separation was achieved on a reversed-phase Eclipse XDB-C18 column (4.6 mm × 150 mm, 5 um) using the eluent of methanol-water (5 mmol/L ammonium acetate) (90:10, v/v, pH 5.8) as mobile phase. The electrospray ionization source was set at the positive multiple reaction monitoring (MRM) mode. This method involved the use of the [M+H]^+ ions of PH and diphenhydramine hydrochloride at m/z 316.4- 128.2 and m/z 256.4-167.2. The calibration curve was linear in the range of 1-1000 ng/mL with a correlation coefficient of 0.9988. The lower limit of quantification was 0.05 ng/mL. The precision, accuracy and recovery of the method were acceptable. Following intravenous injection admires' tration at doses of 0.5, 1 and 5 mg/kg PH, the main pharmacokinetic parameters were as the followings, t1/2a 0.33 h, t1/2β 2.44 1% tmax 0.058 1% AUC and Cmax exhibited a linear increase along with the increase of dose. The two-compartment model fit the three dose groups. This method was sensitive, accurate and fast for the determination of concentration of PH in beagle dog plasma. It could be used in pharmacokinetic studies of PH. 展开更多
关键词 Liquid chromatography-mass spectrometry-mass spectrometry Penehyclidine hydrochloride Eleetrospray ionization PHARMACOKINETICS
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Synthesis and characterization of ZnTiO_3 with high photocatalytic activity 被引量:2
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作者 严欣 赵翠连 +3 位作者 周义龙 吴振军 袁剑民 李文生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第7期2272-2278,共7页
Perovskite ZnTiO3 was prepared through a new method which contained a hydrothermal process for the preparation of titanate nanotubes and an ion-exchange process.The titanate nanotubes were inferred to be H2Ti3O7·... Perovskite ZnTiO3 was prepared through a new method which contained a hydrothermal process for the preparation of titanate nanotubes and an ion-exchange process.The titanate nanotubes were inferred to be H2Ti3O7·3H2O.X-ray diffraction(XRD)result revealed the presence of cubic perovskite phase of ZnTiO3.The unique chain-like morphology of ZnTiO3 was observed by scanning electron microscopy(SEM) and transmission electron microscopy(TEM).UV-Vis diffusive reflection spectra of ZnTiO3indicated that the absorbance obviously increased in the visible light region.The degradation rate of methyl orange solution(15 mg/L)reached 95.3%over ZnTiO3(0.3 g/L) after 20 min xenon light irradiation,which was higher than that using the commercial catalyst P25 under the same reaction condition.The degradation kinetic results follow the first-order equation and the rate constant is 0.1020. 展开更多
关键词 ZnTiO3 ion-exchange PHOTOCATALYSIS PEROVSKITE SYNTHESIS CHARACTERIZATION
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Wear and corrosion resistant coatings on surface of cast A356 aluminum alloy by plasma electrolytic oxidation in moderately concentrated aluminate electrolytes 被引量:12
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作者 谢焕钧 程英亮 +2 位作者 李绍先 曹金晖 曹力 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第2期336-351,共16页
Plasma electrolytic oxidation of a cast A356 aluminum alloy was carried out in aluminate electrolytes to develop wear and corrosion resistant coatings. Different concentrations of 2, 16 and 24 g/L NaAlO2 solutions and... Plasma electrolytic oxidation of a cast A356 aluminum alloy was carried out in aluminate electrolytes to develop wear and corrosion resistant coatings. Different concentrations of 2, 16 and 24 g/L NaAlO2 solutions and a silicate electrolyte (for comparison) were employed for the investigation. Wear performance and corrosion resistance of the coatings were evaluated by WC (tungsten carbide) ball-on-flat dry sliding tests and electrochemical methods, respectively. The results show that the coating formed for a short duration of 480 s in 24 g/L NaAlO2 solution generated the best protection. The coating sustained 30 N load for sliding time of 1800 s, showing very low wear rate of -4.5×10^-7 mm3/(N· m). A low corrosion current density of -8.81×10^-9 A/cm2 was also recorded. Despite low α-Al2O3 content of the coating, the compact and nearly single layer nature of the coating guaranteed the excellent performances. 展开更多
关键词 A356 aluminium alloy sodium aluminate plasma electrolytic oxidation WEAR corrosion
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Tomato Growth and Organic Acid Changes in Response to Partial Replacement of NO_3^--N by NH_4^+-N 被引量:44
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作者 DONGCai-Xia SHENQi-Rong WANGGe 《Pedosphere》 SCIE CAS CSCD 2004年第2期159-164,共6页
A hydroponic experiment was conducted to study the effect of partial replacement of NO-3-N by NH4+-N on the seedling growth and organic acid content of tomato (Lycopersicon esculentum Mill.). A completely randomized d... A hydroponic experiment was conducted to study the effect of partial replacement of NO-3-N by NH4+-N on the seedling growth and organic acid content of tomato (Lycopersicon esculentum Mill.). A completely randomized design was established with three replications and five treatments, i.e., NO-3-N/NH4+-N of 100/0, 75/25, 50/50, 25/75 and 0/100. Results showed that 25% replacement of NO3--N by NH4+-N significantly (P = 0.05) improved fresh and dry weight, revealing that a proper percentage of NH4+-N was important for tomato nitrogen nutrition. This could increase the plant growth even though tomato was a crop that preferred nitrate nutrition. Also an increase in the proportion of NH4+-N in the nutrient solution led to a significant decrease (P = 0.05) in malate, citrate and fumarate. However, the 25% NH4+-N plus 75% NO3--N treatment had no significant effect (P = 0.05) on the 2-ketoglutarate, succinate or oxalic acid content, showing that only some organic acids in tomato plants were affected. Only pyruvate increased significantly (P = 0.05), and it only increased for 25% and 50% replacement of NO3--N by NH4+-N. Metabolism of these organic acids, especially malate, citrate and fumarate, should be further studied at the molecular level in vegetables applied with different nitrogen forms. 展开更多
关键词 NH_4^+-N nitrogen forms NO_3^--N organic acid tomato (Lycopersiconesculentum Mill.)
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The endless tale of non-homologous end-joining 被引量:14
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作者 Eric Weterings David J Chen 《Cell Research》 SCIE CAS CSCD 2008年第1期114-124,共11页
DNA double-strand breaks (DSBs) are introduced in cells by ionizing radiation and reactive oxygen species. In addition, they are commonly generated during V(D)J recombination, an essential aspect of the developing... DNA double-strand breaks (DSBs) are introduced in cells by ionizing radiation and reactive oxygen species. In addition, they are commonly generated during V(D)J recombination, an essential aspect of the developing immune system. Failure to effectively repair these DSBs can result in chromosome breakage, cell death, onset of cancer, and defects in the immune system of higher vertebrates. Fortunately, all mammalian cells possess two enzymatic pathways that mediate the repair of DSBs: homologous recombination and non-homologous end-joining (NHEJ). The NHEJ process utilizes enzymes that capture both ends of the broken DNA molecule, bring them together in a synaptic DNA-protein complex, and finally repair the DNA break. In this review, all the known enzymes that play a role in the NHEJ process are discussed and a working model for the co-operation of these enzymes during DSB repair is presented. 展开更多
关键词 DNA-PK Ku70/80 XRCC4 Ligase IV ARTEMIS XLF Cernunnos DSB NHEJ ATM non-homologous end-joining DNA double-strand break V(D)J recombination
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Deterioration of concrete in railway tunnel suffering from sulfate attack 被引量:10
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作者 龙广成 谢友均 +1 位作者 邓德华 李小坤 《Journal of Central South University》 SCIE EI CAS 2011年第3期881-888,共8页
For the sake of understanding the deterioration behavior of concrete in actual railway tunnel structures subjected to aggressive sulfate medium in practice,detailed field investigations and tested analysis on sprayed ... For the sake of understanding the deterioration behavior of concrete in actual railway tunnel structures subjected to aggressive sulfate medium in practice,detailed field investigations and tested analysis on sprayed concrete linings of approximately 40-year-old railway tunnels in environments containing sulfate ion were carried out,respectively.The results show that the deterioration of concretes in the investigated area is serious,which involves complicated physicochemical process between the sulfate salt and concrete.Among them,the secondary sulfateminerals such as gypsum formation under very high concentration sulfate ion condition by accumulating and evaporation process dominate,followed by the crystallization of sulfate salt and formation of thaumasite. 展开更多
关键词 sulfate attack CONCRETE railway tunnel secondary sulfate minerals salt crystallization
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Ozonation of Sulfur Dioxide in Sulphuric Acid Solution 被引量:2
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作者 刘丽梅 张书廷 +2 位作者 吕学斌 于晓艳 支苏丽 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第7期808-812,共5页
In this study, the oxidation rates of sulfur dioxide (SO2) in sulphuric acid solution by ozone and oxygen were compared, and the oxidation mechanism of ozone on SO2 was investigated. The results showed that the oxid... In this study, the oxidation rates of sulfur dioxide (SO2) in sulphuric acid solution by ozone and oxygen were compared, and the oxidation mechanism of ozone on SO2 was investigated. The results showed that the oxidation-reduction potential of the acidic solution was enhanced, the transformation rate of sulfuric acid to sulphuric acid was increased and the absorption driving force was improved in the presence of ozone. By comparing the amount of sulfate ions measured in the experiments and the theoretical amount of sulfate ions calculated from the amount of ozone consumed in the reaction, it can be confirmed that oxygen free radicals from dissociation of ozone are reactive as an efficient oxidant and oxygen from ozone generator participates in the reaction with SO2. 0.602 mol of effective oxygen was introduced into the reaction by one mole of ozone in 10.15 rain at sulphuric acid concentration of 3% (by mass), SO2 concentration of 1.33% (by volume) and oxygen flow rate of 1.5 L.min^-1 from ozone generator. 展开更多
关键词 OZONE sulfur dioxide DESULFURIZATION sulphuric acid flue gas
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Honeycomb-structured solid acid catalysts fabricated via the swelling-induced self-assembly of acidic poly(ionic liquid)s for highly efficient hydrolysis reactions 被引量:2
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作者 Bihua Chen Tong Ding +6 位作者 Xi Deng Xin Wang Dawei Zhang Sanguan Ma Yongya Zhang Bing Ni Guohua Gao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第2期297-309,共13页
The development of heterogeneous acid catalysts with higher activity than homogeneous acid catalysts is critical and still challenging.In this study,acidic poly(ionic liquid)s with swelling ability(SAPILs)were designe... The development of heterogeneous acid catalysts with higher activity than homogeneous acid catalysts is critical and still challenging.In this study,acidic poly(ionic liquid)s with swelling ability(SAPILs)were designed and synthesized via the free radical copolymerization of ionic liquid monomers,sodium p-styrenesulfonate,and crosslinkers,followed by acidification.The 31P nuclear magnetic resonance chemical shifts of adsorbed trimethylphosphine oxide indicated that the synthesized SAPILs presented moderate and single acid strength.The thermogravimetric analysis results in the temperature range of 300–345°C revealed that the synthesized SAPILs were more stable than the commercial resin Amberlite IR-120(H)(245°C).Cryogenic scanning electron microscopy testing demonstrated that SAPILs presented unique three-dimensional(3D)honeycomb structure in water,which was ascribed to the swelling-induced self-assembly of the molecules.Moreover,we used SAPILs with micron-sized honeycomb structure in water as catalysts for the hydrolysis of cyclohexyl acetate to cyclohexanol,and determined that their catalytic activity was much higher than that of homogeneous acid catalysts.The equilibrium concentrations of all reaction components inside and outside the synthesized SAPILs were quantitatively analyzed using a series of simulated reaction mixtures.Depending on the reaction mixture,the concentration of cyclohexyl acetate inside SAPIL-1 was 7.5–23.3 times higher than that outside of it,which suggested the high enrichment ability of SAPILs for cyclohexyl acetate.The excellent catalytic performance of SAPILs was attributed to their 3D honeycomb structure in water and high enrichment ability for cyclohexyl acetate,which opened up new avenues for designing highly efficient heterogeneous acid catalysts that could eventually replace conventional homogeneous acid catalysts. 展开更多
关键词 Heterogeneous acid catalyst Acidic poly(ionic liquid) SWELLING 3D honeycomb structure Enrichment Hydrolysis HYDRATION
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Ursodeoxycholic acid and superoxide anion 被引量:2
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作者 Predrag Ljubuncic Omar Abu-Salach Arieh Bomzon 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第31期4875-4878,共4页
AIM: To investigate the ability of ursodeoxycholic acid (UDCA) to scavenge superoxide anion (O2-).METHODS: We assessed the ability of UDCA to scavenge (O2-) generated by xanthine-xanthine oxidase (X-XO) in a cell-free... AIM: To investigate the ability of ursodeoxycholic acid (UDCA) to scavenge superoxide anion (O2-).METHODS: We assessed the ability of UDCA to scavenge (O2-) generated by xanthine-xanthine oxidase (X-XO) in a cell-free system and its effect on the rate of O2--induced ascorbic acid (AA) oxidation in hepatic post-mitochondrial supernatants.RESULTS: UDCA at a concentration as high as 1 mmol/Ldid not impair the ability of the X-XO system to generate O2-, but could scavenge O2- at concentrations of 0.5 and 1 mmol/L, and decrease the rate of AA oxidation at a concentration of 100 μmol/L.CONCLUSION: UDCA can scavenge O2-, an action that may be beneficial to patients with primary biliary cirrhosis. 展开更多
关键词 Ursodeoxycholic acid Superoxide anion ANTIOXIDANT
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Role of Low-Molecule-Weight Organic Acids and Their Salts in Regulating Soil pH 被引量:6
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作者 LI Zhi-An ZOU Bi XIA Han-Ping DING Yong-Zhen TAN Wan-Neng FU Sheng-Lei 《Pedosphere》 SCIE CAS CSCD 2008年第2期137-148,共12页
The process of organic materials increasing soil pH has not yet been fully understood. This study examined the role of cations and organic anions in regulating soil pH using organic compounds. Calcareous soil, acid so... The process of organic materials increasing soil pH has not yet been fully understood. This study examined the role of cations and organic anions in regulating soil pH using organic compounds. Calcareous soil, acid soil, and paddy soil were incubated with different simple organic compounds, pH was determined periodically and CO2 emission was also measured. Mixing organic acids with the soil caused an instant decrease of soil pH. The magnitude of pH decrease depended on the initial soil acidity and dissociation degree of the acids. Decomposition of organic acids could only recover the soil pH to about its original level. Mixing organic salts with soil caused an instant increase of soil pH. Decomposition of organic salts of sodium resulted in a steady increase of soil pH, with final soil pH being about 2.7-3.2 pH units over the control. Organic salts with the same anions (citrate) but different cations led to different magnitudes of pH increase, while those having the same cations but different anions led to very similar pH increases. Organic salts of sodium and sodium carbonate caused very similar pH increases of soil when they were added to the acid soil at equimolar concentrations of Na^+. The results suggested that cations played a central role in regulating soil pH. Decarboxylation might only consume a limited number of protons. Conversion of organic salts into inorganic salts (carbonate) was possibly responsible for pH increase during their decomposition, suggesting that only those plant residues containing high excess base cations could actually increase soil pH. 展开更多
关键词 acid soil CATION DECARBOXYLATION organic compounds soil acidity
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