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Study of ionizable drugs transfer across the water/1,2-dichloroethane interface with phase volume ratio equal to unity using a three-electrode system
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作者 ZHANG Meiqin SUN Peng +3 位作者 CHEN Yong LI Fei GAO Zhao SHAO Yuanhua 《Chinese Science Bulletin》 SCIE EI CAS 2003年第12期1234-1239,共2页
The electrochemical behavior of ionizable drugs (Amitriptyline, Diphenhydramine and Trihexyphene- dyl) at the water/1,2-dichloroethane interface with the phase volume ratio (r = Vo/Vw) equal to 1 are investigated by c... The electrochemical behavior of ionizable drugs (Amitriptyline, Diphenhydramine and Trihexyphene- dyl) at the water/1,2-dichloroethane interface with the phase volume ratio (r = Vo/Vw) equal to 1 are investigated by cyclic voltammetry. The system is composed of an aqueous droplet supported at an Ag/AgCl disk electrode and it was covered with an organic solution. In this manner, a conventional three-electrode potentiostat can be used to study the ioni-zable drugs transfer process at a liquid/liquid interface. Physicochemical parameters such as the formal transfer potential, the Gibbs energy of transfer and the standard par-tition coefficients of the ionized forms of these drugs can be evaluated from cyclic voltammograms obtained. The ob-tained results have been summarized in ionic partition dia-grams, which are a useful tool for predicting and interpret-ing the transfer mechanisms of ionizable drugs at the liq-uid/liquid interfaces and biological membranes. 展开更多
关键词 water/1 2-dichloroethane INTERFACE ionizable drug trans-fer three-electrode SYSTEM PHASE volume ratio ionic partition dia-gram.
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血清水通道蛋白1水平联合血管外肺水指数对脓毒症致急性呼吸窘迫综合征的价值
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作者 周峰 尹其翔 +3 位作者 魏法星 林海敏 蔡华忠 陈义坤 《实用医学杂志》 CAS 北大核心 2024年第17期2483-2488,共6页
目的 探讨血清水通道蛋白1(AQP1)水平联合血管外肺水指数(EVLWI)对脓毒症致急性呼吸窘迫综合征(ARDS)的病情程度及预后的评估价值。方法 选取2020年1月至2023年12月收治的脓毒症致ARDS患者268例(ARDS组)和单纯脓毒症患者55例(单纯脓毒症... 目的 探讨血清水通道蛋白1(AQP1)水平联合血管外肺水指数(EVLWI)对脓毒症致急性呼吸窘迫综合征(ARDS)的病情程度及预后的评估价值。方法 选取2020年1月至2023年12月收治的脓毒症致ARDS患者268例(ARDS组)和单纯脓毒症患者55例(单纯脓毒症组),脓毒症致ARDS患者根据氧合指数(OI)分为轻度组89例、中度组109例、重度组70例,根据28 d预后分为死亡组104例和存活组164例。检测血清AQP1水平和计算EVLWI。利用Spearman法,脓毒症致ARDS患者血清AQP1水平、EVLWI与OI的相关性;建立logistic回归模型,确定脓毒症致ARDS患者死亡的因素;并绘制ROC曲线,评价血清AQP1水平联合EVLWI对其的评估价值。结果 与单纯脓毒症组比较,ARDS组血清AQP1水平降低,EVLWI升高(P <0.05)。AQP1水平在轻度、中度、重度组中依次降低,EVLWI依次升高(P <0.05)。血清AQP1水平与脓毒症致ARDS患者OI呈正相关,EVLWI与脓毒症致ARDS患者OI呈负相关(P <0.05)。268例脓毒症致ARDS患者28 d死亡率38.81%(104/268)。脓毒症致ARDS患者死亡的独立保护因素为OI升高(OR=0.984,95%CI:0.976~0.992)和AQP1升高(OR=0.761,95%CI:0.677~0.854),独立危险因素为SOFA评分增加(OR=1.367,95%CI:1.142~1.636)和血乳酸升高(OR=2.515,95%CI:1.689~3.745)、EVLWI升高(OR=1.559,95%CI:1.290~1.885),差异有统计学意义(P <0.05)。血清AQP1水平联合EVLWI预测的AUC为0.887(95%CI:0.843~0.923),比血清AQP1水平、EVLWI单独预测的0.792(95%CI:0.738~0.839)、0.807(95%CI:0.754~0.852)大(P <0.05)。结论 血清AQP1水平降低和EVLWI升高与脓毒症致ARDS患者病情程度加重、预后不良有关,血清AQP1水平联合EVLWI对脓毒症致ARDS患者预后的评估价值较高。 展开更多
关键词 脓毒症 急性呼吸窘迫综合征 水通道蛋白1 血管外肺水指数
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基于Sentinel-1/2改进极化指数和纹理特征的土壤含盐量反演模型 被引量:1
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作者 张智韬 贺玉洁 +3 位作者 殷皓原 项茹 陈俊英 杜瑞麒 《农业机械学报》 EI CAS CSCD 北大核心 2024年第1期175-185,共11页
目前Sentinel-1/2协同反演植被土壤含盐量的研究大多是基于Sentinel-2光谱信息和Sentinel-1后向散射系数,没有考虑Sentinel-2光谱信息容易受土壤亮度等信息影响,Sentinel-1后向散射系数容易受土壤粗糙度和水分影响。为进一步提高Sentine... 目前Sentinel-1/2协同反演植被土壤含盐量的研究大多是基于Sentinel-2光谱信息和Sentinel-1后向散射系数,没有考虑Sentinel-2光谱信息容易受土壤亮度等信息影响,Sentinel-1后向散射系数容易受土壤粗糙度和水分影响。为进一步提高Sentinel-1/2协同反演植被土壤含盐量的精度,用水云模型对雷达卫星后向散射系数进行校正,消除植被影响;然后协同Sentinel-2纹理特征,基于VIP、OOB、PCA 3种变量筛选和RF、ELM、Cubist 3种机器学习回归模型构建植被土壤含盐量反演模型。研究结果表明:经过水云模型去除植被影响后的雷达后向散射系数及其极化组合指数与土壤含盐量的相关性有一定程度的提高。不同变量选择方法与不同机器学习方法耦合模型在反演土壤含盐量中,OOB变量筛选方法与RF、ELM和Cubist 3种机器学习方法的耦合模型精度最佳,建模集和验证集的R2都在0.750以上,且验证集的RMSE和MAE均最小;其中OOB-Cubist耦合模型精度最高,且R_(v)^(2)/R_(c)^(2)为0.955,具有良好的鲁棒性。研究可为机器学习协同物理模型、光学卫星协同雷达卫星在土壤含盐量反演中的进一步应用提供思路。 展开更多
关键词 土壤含盐量 Sentinel-1/2 纹理特征 水云模型 机器学习 改进极化指数
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基于Hydrolight模型的太湖SDGSAT-1卫星悬浮物浓度反演研究
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作者 王雅萍 胡雪可 +4 位作者 李家国 姜晟 陈兴峰 赵利民 陈洪真 《航天返回与遥感》 CSCD 北大核心 2024年第1期174-186,共13页
利用卫星遥感反演水体中的悬浮物浓度对水质监测和保护具有重要意义,在悬浮物浓度反演过程中,如何避免或最大程度降低水体中叶绿素a、有色可溶性有机物(Colored Dissolved Organic Matter,CDOM)的干扰是当前的技术难点。文章针对可持续... 利用卫星遥感反演水体中的悬浮物浓度对水质监测和保护具有重要意义,在悬浮物浓度反演过程中,如何避免或最大程度降低水体中叶绿素a、有色可溶性有机物(Colored Dissolved Organic Matter,CDOM)的干扰是当前的技术难点。文章针对可持续发展科学卫星1号(SDGSAT-1)MII传感器,利用Hydrolight辐射传输模型,从理论上挖掘只与悬浮物强相关的反演因子,以此构建适用于MII影像的太湖悬浮物浓度反演模型,通过水体的实测数据和遥感数据对模型应用效果进行验证。结果表明:反演因子R′(B_5/B_3)与悬浮物浓度为强相关,同时与叶绿素a、CDOM浓度弱相关;利用R′(B_5/B_3)作为反演因子构建的幂函数模型为最优反演模型;将幂函数模型分别应用于实测数据和2022年5月4日的太湖SDGSAT-1 MII数据,两次验证试验显示反演结果和现场测量结果具有较强一致性,模型适用性较好。该研究可为SDGSAT-1卫星在湖泊水体悬浮物浓度监测、水资源评估与保护等提供一些技术参考。 展开更多
关键词 悬浮物浓度反演 可持续发展科学卫星1 相关性 水体辐射传输模拟 遥感应用
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Liquid-Liquid Equilibrium for 1-Butanol-Water-KF and 1-Butanol-Water-K_2CO_3 Systems 被引量:3
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作者 XU Wen-you JI Min 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第5期892-896,共5页
KF or K2CO3 was added into the 1-butanol-water system and two phases were formed: water-rich phase (water phase) and 1-butanol-rich phase (1-butanol phase). The liquid liquid equilibrium (LLE) data for 1-butano... KF or K2CO3 was added into the 1-butanol-water system and two phases were formed: water-rich phase (water phase) and 1-butanol-rich phase (1-butanol phase). The liquid liquid equilibrium (LLE) data for 1-butanol-water-KF and 1-butanol-water-K2CO3 systems were measured at 25℃ and showed that 1-butanol phase contained negligible salt and water phase contained negligible 1-butanol when the concentrations of KF and K2CO3 in the water phase were equal to or higher than 27.11% and 31.68% , respectively. Thus water could be separated efficiently from 1-butanol-water by adding KF or K2CO3 into the system. A theoretical calculation of LLE data was calculated by using the Pitzer theory to get water activity in the water phase, and by the models, such as the Wilson, NRTL or the UNIQUAC for the 1-butanol phase. For 1-hutanol-water-KF system, the experimental data were found in good agreement with the calculated results by using Pitzer theory and Wilson equa tion, while for 1-butanol-water-K2CO3 system, the experimental data were found in good agreement with the calculated results by using Pitzer theory and UNIQUAC eauation. 展开更多
关键词 1-butanol-water-KF 1-butanol-water-K2CO3 liquid-liquid equilibrium Pitzer equation Wilson equation NRTL equation UNIQUAC equation salting-out effect
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伊宁1井和伊宁2井井水温梯度测量及结果分析
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作者 颜龙 梁卉 +2 位作者 廉殷朝 闫玮 王斌 《大地测量与地球动力学》 CSCD 北大核心 2024年第11期1186-1192,共7页
通过对喀什河断裂带上、下盘的伊宁2井和伊宁1井进行水温梯度测量和水样水化学分析,结合区域地质资料和井孔柱状图,分析两口观测井的水温梯度变化特征及影响因素。结果表明,伊宁1井水温变化以地温控制为主,伊宁2井水温受补给水源水温和... 通过对喀什河断裂带上、下盘的伊宁2井和伊宁1井进行水温梯度测量和水样水化学分析,结合区域地质资料和井孔柱状图,分析两口观测井的水温梯度变化特征及影响因素。结果表明,伊宁1井水温变化以地温控制为主,伊宁2井水温受补给水源水温和地温的综合影响;伊宁1井地下水的水岩反应程度和循环深度均高于伊宁2井,不同水岩反应程度和循环深度的补给水源会在一定程度上影响观测井的水温梯度变化。地层裂隙发育程度和含水层分布情况是导致水温梯度表现出复杂变化特征的主要因素,伊宁2井所处区域岩体相对破碎,裂隙发育,水温梯度波动大;伊宁1井所处区域岩体相对完整,水温梯度相对稳定。 展开更多
关键词 伊宁1 伊宁2井 水温梯度 水化学 含水层
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ASME PCC-1与Taylor-Waters法螺栓载荷计算分析与对比 被引量:7
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作者 袁成乾 杨建良 《压力容器》 北大核心 2019年第7期44-47,33,共5页
对ASME PCC-1与GB/T 150. 3-2011中(Taylor-Waters法)螺栓载荷计算模型进行了分析与对比。以两组数据进行了实例计算和数据分析。从分析结果可以看出,两种计算方法对于螺栓载荷的计算模型基本一致,但按照ASME PCC-1算得的需要螺栓面积... 对ASME PCC-1与GB/T 150. 3-2011中(Taylor-Waters法)螺栓载荷计算模型进行了分析与对比。以两组数据进行了实例计算和数据分析。从分析结果可以看出,两种计算方法对于螺栓载荷的计算模型基本一致,但按照ASME PCC-1算得的需要螺栓面积远大于Taylor-Waters法算得的面积。这对法兰接头的设计有很大的影响,对按照ASME PCC-1和API 660等标准进行非标法兰的设计有参考意义。 展开更多
关键词 ASME PCC-1 Taylor-waters法 法兰 螺栓载荷
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新集矿区深部1煤层底板奥灰岩溶突水危险性评价 被引量:1
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作者 韩锋 詹润 +3 位作者 孙贵 顾承串 李宏泽 雷震 《合肥工业大学学报(自然科学版)》 CAS 北大核心 2024年第8期1080-1086,共7页
奥灰岩溶裂隙含水层是影响华北型煤矿深部开采的重要水害,在水-岩相互作用下奥灰含水层易导致煤层底板突水。为进一步认识奥灰岩溶突水问题,文章以新集矿区深部1煤层开采为例,利用矿区近些年最新积累的奥灰钻孔资料,选取断层强度指数、... 奥灰岩溶裂隙含水层是影响华北型煤矿深部开采的重要水害,在水-岩相互作用下奥灰含水层易导致煤层底板突水。为进一步认识奥灰岩溶突水问题,文章以新集矿区深部1煤层开采为例,利用矿区近些年最新积累的奥灰钻孔资料,选取断层强度指数、断层交叉点与尖灭点、含水层水压、富水性、隔水层等效厚度、脆塑比7个因素作为奥灰岩溶突水的主控因素,并结合层次分析法(analytic hierarchy process,AHP)确定各主控因素影响权重。运用地理信息系统(geographic information system,GIS)空间分析功能建立各主控因素专题图,通过对专题栅格图归一化处理,将各主控因素按照权重进行空间复合叠加,最终获得1煤层底板奥灰岩溶突水危险性评价分区结果。将评价结果与突水系数法计算结果对比分析可知,基于GIS的煤层底板突水危险性评价方法更符合矿区实际地质情况,可以为矿区深部煤层开采与水害防治工作提供参考依据。 展开更多
关键词 层次分析法(AHP) 地理信息系统(GIS) 新集矿区 1煤层 底板 奥陶系灰岩 突水
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Effects of natural mineral-rich water consumption on the expression of sirtuin 1 and angiogenic factors in the erectile tissue of rats with fructose-induced metabolic syndrome 被引量:2
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作者 Cidalia D Pereira Milton Severo +2 位作者 Luisa Rafael Maria Joao Martins Delminda Neves 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第4期631-638,共8页
Consuming a high-fructose diet induces metabolic syndrome (MS)-Iike features, including endothelial dysfunction. Erectile dysfunction is an early manifestation of endothelial dysfunction and systemic vascular diseas... Consuming a high-fructose diet induces metabolic syndrome (MS)-Iike features, including endothelial dysfunction. Erectile dysfunction is an early manifestation of endothelial dysfunction and systemic vascular disease. Because mineral deficiency intensifies the deleterious effects of fructose consumption and mineral ingestion is protective against MS, we aimed to characterize the effects of 8weeks of natural mineral-rich water consumption on the structural organization and expression of vascular growth factors and receptors on the corpus cavernosum (CC) in 10% fructose-fed Sprague-Dawley rats (FRUCT). Differences were not observed in the organization of the CC either on the expression of vascular endothelial growth factor (VEGF) or the components of the angiopoietins/Tie2 system. However, opposing expression patterns were observed for VEGF receptors (an increase and a decrease for VEGFR1 and VEGFR2, respectively) in FRUCT animals, with these patterns being strengthened by mineral-rich water ingestion. Mineral-rich water ingestion (FRUCTMIN) increased the proportion of smooth muscle cells compared with FRUCT rats and induced an upregulatory tendency of sirtuin I expression compared with the control and FRUCT groups. Western blot results were consistent with the dual immunofluorescence evaluation. Plasma oxidized low-density lipoprotein and plasma testosterone levels were similar among the experimental groups, although a tendency for an increase in the former was observed in the FRUCTMIN group. The mineral-rich water-treated rats presented changes similar to those observed in rats treated with MS-protective polyphenol-rich beverages or subjected to energy restriction, which led us to hypothesize that the effects of mineral-rich water consumption may be more vast than those directly observed in this study. 展开更多
关键词 ANGIOPOIETINS erectile tissue hypersaline sodium-rich naturally sparkling mineral water receptors sirtuin 1 vascularendothelial growth factor
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Oxa-Pictet-Spengler reaction in water.Synthesis of some(±)-1-aryl-6,7-dimethoxyisochromans
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作者 Aamer Saeed 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期261-264,共4页
An acid catalyzed oxa-Pictet-Spengler reaction‘on water leading to the synthesis of a variety of l-aryl-6,7-dimethoxyisochro-mans is described.The aqueous chemistry is a much cleaner,efficient,cheaper and simple meth... An acid catalyzed oxa-Pictet-Spengler reaction‘on water leading to the synthesis of a variety of l-aryl-6,7-dimethoxyisochro-mans is described.The aqueous chemistry is a much cleaner,efficient,cheaper and simple method for synthesis.The scope of reactions was extended to thia-Pictet-Spengler reaction to afford the some isothiochromans. 展开更多
关键词 Oxa-Pictet-Spengler reaction In water 1-Aryl-6 7-dimethoxyisochromans Isothiochromans
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Influence of Initial Water Content on Synthesis of Silicalite-1 Zeolite 被引量:1
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作者 Zhang Honghan Zhang Shanhe +1 位作者 Wang Haoren Li Chunyi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2017年第4期11-19,共9页
The effect of initial water content on the synthesis of silicalite-1 zeolite and its reaction performance in methanol to propylene(MTP) reaction was comprehensively investigated. The as-synthesized samples were charac... The effect of initial water content on the synthesis of silicalite-1 zeolite and its reaction performance in methanol to propylene(MTP) reaction was comprehensively investigated. The as-synthesized samples were characterized by XRD,N_2 adsorption and desorption, SEM, and FTIR techniques, and studied for the methanol to propylene(MTP) reaction. The results showed that the initial water content played a crucial role on the particle size and porous structure of the silicalite-1 zeolites. It was found that adding initial water to reach a certain amount, the crystal size reduced obviously and the mesoporous structure appeared. Upon applying the silicalite-1 zeolite samples in the MTP reaction, they showed excellent catalytic performance to reach a highest propene mass yield of 26.81%(on the CH_2 basis) and a P/E ratio of 6.28 in 2 h. The excellent catalytic performance of silicalite-1 can be attributed to its mesoporous structure. 展开更多
关键词 INITIAL water content HIERARCHICAL PORE SILICALITE-1 MTP
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基于不同含水量基质下黔藿1号种子萌发过程中代谢组学差异分析
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作者 熊毅 汪卓逸 +5 位作者 汪永平 龙海成 丁邦勇 王华磊 罗春丽 刘红昌 《种子》 北大核心 2024年第6期28-35,F0002,共9页
为研究水分对黔藿1号种子萌发的影响,检测育苗基质不同含水量下种子不同萌发阶段相关代谢产物和代谢途径的变化,以黔藿1号种子为试验材料,采用广靶代谢组学方法对育苗基质不同含水量下黔藿1号种子萌发过程的代谢途径及其代谢物变化等进... 为研究水分对黔藿1号种子萌发的影响,检测育苗基质不同含水量下种子不同萌发阶段相关代谢产物和代谢途径的变化,以黔藿1号种子为试验材料,采用广靶代谢组学方法对育苗基质不同含水量下黔藿1号种子萌发过程的代谢途径及其代谢物变化等进行分析。结果表明,基质含水量为200%时,有利于黔藿1号种子萌发。在基质含水量分别为100%和200%条件下,种子萌发过程中的代谢物种类变化相似,主要有氨基酸及其衍生物、糖类、黄酮、生物碱等,其中差异代谢物显著富集到精氨酸和脯氨酸代谢、鞘磷脂代谢、黄酮类生物合成等通路。在基质含水量200%较100%下,二氢茉莉酸、桂酸桂酯的相对含量随着种子萌发时间后移呈先升后降的趋势,可能是促进种子萌发的原因之一。 展开更多
关键词 黔藿1 种子萌发 含水量 代谢组学
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Effect of 1-MCP on Gas Exchange and Carbohydrate Concentrations of the Cotton Flower and Subtending Leaf under Water-Deficit Stress 被引量:1
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作者 Dimitra A. Loka Derrick M. Oosterhuis 《American Journal of Plant Sciences》 2013年第1期142-152,共11页
Ethylene is an endogenous plant hormone that increases under adverse environmental conditions, resulting in leaf and fruit abscission and ultimately yield reduction. In cotton, however, the effects of water-deficit st... Ethylene is an endogenous plant hormone that increases under adverse environmental conditions, resulting in leaf and fruit abscission and ultimately yield reduction. In cotton, however, the effects of water-deficit stress on ethylene production have been uncertain. In this study it was hypothesized that application of an ethylene inhibitor 1-Methylcyclo- propene (1-MCP) would prevent ethylene production and result in alleviation of water-deficit stress consequences on the physiology and metabolism of the cotton flower and subtending leaf. To test this hypothesis, growth chamber experiments were conducted in 2009-2010 with treatments consisting of (C) untreated well-watered control, (C + 1MCP) well-watered plus 1-MCP, (WS) untreated water-stressed control, and (WS + 1MCP) water-stressed plus 1-MCP. The plants were subjected to two consecutive drying cycles during flowering, approximately 8 weeks after planting, and 1-MCP was foliar applied at a rate of 10g. ai/ha at the beginning of each drying cycle. The results showed that 1-MCP application had no significant effect on gas exchange functions and did not prevent reductions from water stress in leaf photosynthesis, respiration and stomatal conductance. However, application of 1-MCP resulted in a decrease in sucrose content of water-stressed pistils compared to the control indicating that 1-MCP has the potential to interfere in carbohydrate metabolism of reproductive units. 展开更多
关键词 COTTON 1-Methylcyclopropene Ethylene water-DEFICIT Stress Carbohydrates Gas Exchange
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2018-2022年青海省主要湖泊蓄水量时空变化数据集
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作者 张怀文 曹引 +3 位作者 赵红莉 蒋云钟 严登明 赵慧子 《中国科学数据(中英文网络版)》 CSCD 2024年第1期314-327,共14页
青海省是中国西北部重要的生态功能区,水资源总量丰富,但时空分布极不均匀,且由于气候、地理环境等因素的影响,大部分湖泊长期缺乏监测。而湖泊作为地表水水资源的重要载体,是研究气候变化和人类活动对水循环过程影响的重要指示器。国... 青海省是中国西北部重要的生态功能区,水资源总量丰富,但时空分布极不均匀,且由于气候、地理环境等因素的影响,大部分湖泊长期缺乏监测。而湖泊作为地表水水资源的重要载体,是研究气候变化和人类活动对水循环过程影响的重要指示器。国产高分一号、六号卫星宽幅相机空间分辨率为16 m,组网运行可实现2天重复观测,可以高频次获取地表水体面积;ICESat-2激光测高数据具备厘米级的测高精度,可以获取高精度的地表水体测高水位。本数据集基于GF-1/6WFV水体面积和ICESat-2测高水位构建青海省湖泊蓄水量遥感监测模型,通过遥感手段对青海省湖泊蓄水量进行时空变化监测。经验证,本数据集中湖泊蓄变量监测精度总体优于93%,满足湖泊蓄水量时空变化遥感监测需求。本数据集在时间尺度上涵盖2018-2022年,共计60期月度监测结果;空间尺度上覆盖了青海省面积大于30 km^(2)的33个湖泊,主要集中分布在青海省西部、北部、东南部,可为青海省湖泊、水文与气候变化过程监测、水资源动态评价、优化水资源管理与调度提供基础数据支撑。 展开更多
关键词 湖泊蓄水量 GF-1/6 WFV ICESat-2 青海省 2018-2022年
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Isobaric Vapor–Liquid Equilibrium for tert-Butyl Alcohol + Water + Propane-1,3-Diol + 1-Ethyl-3-Methylimidazolium Chloride at 101.3 kPa
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作者 Xianbao Cui Qinglong Cheng +5 位作者 Haofei Liu Lexing Xue Jinbo Zhou Ying Zhang Tianyang Feng Kai Zhang 《Transactions of Tianjin University》 EI CAS 2018年第5期424-433,共10页
In this study, we used a mixture of organic liquid propane-1,3-diol and ionic liquid 1-ethyl-3-methylimidazolium chloride([emim]Cl) as the entrainer to separate tert-butyl alcohol(TBA) + water. We measured the isobari... In this study, we used a mixture of organic liquid propane-1,3-diol and ionic liquid 1-ethyl-3-methylimidazolium chloride([emim]Cl) as the entrainer to separate tert-butyl alcohol(TBA) + water. We measured the isobaric vapor–liquid equilibrium(VLE) for the quaternary system TBA + water + propane-1,3-diol + [emim]Cl at 101.3 kPa, and found the VLE data to be well correlated with the nonrandom two-liquid model. These results show that the mixed solvent of propane-1,3-diol + [emim]Cl can increase the relative volatility of TBA to water and break the azeotropic point. We found no notable synergetic effect between them, and observed that the liquid mixed solvent of propane-1,3-diol and [emim]Cl had lower viscosity than [emim]Cl, which makes it a promising entrainer for separating the TBA + water azeotrope in industrial applications. 展开更多
关键词 tert-Butyl alcohol·water·Propane-1-3-diol·1-Ethyl-3-methylimidazolium chloride·Vapor–liquid EQUILIBRIUM
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Determination and Correlation of 1-Octanol/Water Partition Coefficients for Six Quinolones from 293.15 K to 323.15 K
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作者 ZHANG Cong-liang WANG Yan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第4期636-639,共4页
A shake-flask method was used to determine 1-octanol/water partition coefficients of ofloxacin, norfloxacin, lomefloxacin, ciprofloxacin, pefloxacin and pipemidic acid from 293.15 K to 323.15 K. The results show that ... A shake-flask method was used to determine 1-octanol/water partition coefficients of ofloxacin, norfloxacin, lomefloxacin, ciprofloxacin, pefloxacin and pipemidic acid from 293.15 K to 323.15 K. The results show that 1-octanol/water partition coefficient of each quinolone increased with the increase of temperature. Based on the fluid phase equilibrium theory, the thermodynamic relationship of 1-octanol/water partition coefficient depending on the temperature was proposed, and the changes of enthalpy, entropy, and Gibbs free energy for quinolones partitioning in 1-octanol/water were determined, respectively. Quinolones molecules partitioning in 1-octanol/water was mainly an entropy driving process, during which the order degree of system decreased. The temperature effects of 1-octanol/water partition coefficient were investigated. The results show that its magnitude is the same as the values in the literature. 展开更多
关键词 QUINOLONE 1-Octanol/water partition coefficient THERMODYNAMICS
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Water-Deficit Response Is Not Affected by Glutathione Deficiency in Arabidopsis thaliana pad2-1 Plants
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作者 Tana Jubany-Marí Seán Meehan +1 位作者 Marta López-Carbonell Leonor Alegre 《American Journal of Plant Sciences》 2016年第14期2020-2037,共18页
Changes in glutathione and ascorbate content, hydrogen peroxide and abscisic acid were studied in developing leaves in wild-type (Col-0) and glutathione-deficient mutant pad2-1 lines of Arabidopsis thaliana over a tim... Changes in glutathione and ascorbate content, hydrogen peroxide and abscisic acid were studied in developing leaves in wild-type (Col-0) and glutathione-deficient mutant pad2-1 lines of Arabidopsis thaliana over a time period of 9 days of drought followed by re-watering. Glutathione deficient mutant (pad2-1) presents mechanisms of acclimation to water stress through the reduction of plant biomass and increase in endogenous concentrations of ascorbate and glutathione. These acclimation responses to stress appeared along with the first symptoms of stress and we suggest here that they are regulated by ABA and H<sub>2</sub>O<sub>2</sub>. Normally, wild type plants under conditions of stress require an initial response phase in which a decrease in antioxidants is observed before reaching acclimation through the increase in levels of antioxidants. pad2-1 is more sensitive to stress and reacts to it;however, it did not suffer more oxidative stress than Col-0 plants, even though pad2-1 had higher levels of endogenous H<sub>2</sub>O<sub>2</sub> relative to wild-type. In both water stressed Col-0 and pad2-1 plants increases in ABA were observed, however, more sharply in wild-type stressed plants. Low levels of glutathione together with high levels of H<sub>2</sub>O<sub>2</sub> may regulate endogenous ABA concentrations and could be related to the slow growth rates which were observed during the experiment. The results highlighted the double function of glutathione as an antioxidant and signal molecule and also, the different response patterns of wild-type and pad2-1 when faced with drought stress. The results bring new insights to the responses of pad2-1 under conditions of water stress. 展开更多
关键词 Abscisic Acid ANTIOXIDANTS Growth Hydrogen Peroxide pad2-1 water Stress
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基于Sentinel-1 SAR数据的鄱阳湖水体提取方法对比研究
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作者 郭丽清 况润元 《水文》 CSCD 北大核心 2024年第5期68-74,共7页
遥感水体提取技术在水体规划与监测中发挥着关键作用。针对Sentinel-1 SAR数据的水体提取,首先分析水体及其周围主要地物的后向散射特性,其次引入纹理、地形特征,对比分析阈值法、分类器法和面向对象法的水体提取效果,最后针对鄱阳湖的... 遥感水体提取技术在水体规划与监测中发挥着关键作用。针对Sentinel-1 SAR数据的水体提取,首先分析水体及其周围主要地物的后向散射特性,其次引入纹理、地形特征,对比分析阈值法、分类器法和面向对象法的水体提取效果,最后针对鄱阳湖的典型水体环境,提出不同方法的应用策略,以便更有效地提取水体。研究表明:多特征融合提取可减少水体信息的混淆;RF算法对细小水体和边界的提取相对精细,总体精度高达97.8%;针对含有植被的浅水区,SDWI、Otsu等阈值法展现出更好的识别能力;水面上的船体对水体提取的完整性造成影响。研究探讨了Sentinel-1 SAR数据在鄱阳湖水体提取中的方法适用性,以期为鄱阳湖的水资源监测提供技术支持。 展开更多
关键词 Sentinel-1 SAR 水体提取 鄱阳湖 阈值法 分类器法
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Hydroaminomethylation of 1-Dodecene Catalyzed by Water-soluble Rhodium Complex
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作者 YingYongWANG MeiMingLUO +2 位作者 YaoZhongLI HuaCHEN XianJunLI 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第7期774-776,共3页
The hydroaminomethylation of 1-dodecene catalyzed by water soluble rhodium complex RhCl(CO)(TPPTS)2 in the presence of surfactant CTAB was investigated. High reactivity and selectivity for tertiary amine were achieved... The hydroaminomethylation of 1-dodecene catalyzed by water soluble rhodium complex RhCl(CO)(TPPTS)2 in the presence of surfactant CTAB was investigated. High reactivity and selectivity for tertiary amine were achieved under relatively mild conditions. 展开更多
关键词 HYDROAMINOMETHYLATION 1-DODECENE water-soluble rhodium complex biphasic catalytic system.
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陈皮提取物对APP/PS-1双转基因阿尔茨海默病小鼠学习记忆功能的影响
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作者 颜仁梁 李威 《福建医药杂志》 CAS 2024年第3期107-110,共4页
目的探讨陈皮提取物对APP/PS-1双转基因阿尔茨海默病(AD)小鼠学习记忆功能的影响.方法选用APP/PS-1双转基因AD小鼠16只,随机分为模型对照组和供试品组,8只/组,另取8只C57小鼠为正常对照组,正常对照组和模型对照组分别灌胃等量的生理盐水... 目的探讨陈皮提取物对APP/PS-1双转基因阿尔茨海默病(AD)小鼠学习记忆功能的影响.方法选用APP/PS-1双转基因AD小鼠16只,随机分为模型对照组和供试品组,8只/组,另取8只C57小鼠为正常对照组,正常对照组和模型对照组分别灌胃等量的生理盐水,供试品组灌胃陈皮提取物的生理盐水溶解液,灌胃体积为10mL/kg,1次/d,连续18d.第11天到第16天,进行Morris水迷宫的定位航行实验及空间探索实验.第17天到第18天,进行5min避暗实验.结果在Morris水迷宫实验中,与正常对照组比较,模型对照组定位航行第2天、第3天、第5天的潜伏期增加(P<0.05);与模型对照组比较,供试品组第5天的潜伏期降低(P<0.05).空间探索阶段,各组的目标象限路程百分比、时间百分比及站台穿越次数差异无统计学意义(P>0.05).在避暗实验中各组的错误潜伏期、错误次数及错误率差异均无统计学意义(P>0.05).结论陈皮提取物对APP/PS-1双转基因AD小鼠的空间学习、记忆能力有一定的改善作用. 展开更多
关键词 陈皮提取物 APP/PS-1双转基因AD小鼠 MORRIS水迷宫实验 避暗实验
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