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Design of 2,4-Dichlorophenoxyacetic Acid Imprinted Polymer with High Specificity and Selectivity 被引量:2
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作者 Kizhakekuthiathottil Mathew Annamma Mathew Beena 《Materials Sciences and Applications》 2011年第3期131-140,共10页
A widely used herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) was imprinted on poly (4-vinylpyridine) (4-VP) using (40%) ethyleneglycol dimethacrylate (EGDMA) as crosslinking agent. The classical imprinting technolog... A widely used herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) was imprinted on poly (4-vinylpyridine) (4-VP) using (40%) ethyleneglycol dimethacrylate (EGDMA) as crosslinking agent. The classical imprinting technology makes use of a high degree of crosslinking which does not allow the template molecules to move freely. So the binding sites, located in the central area of the three dimensional polymer matrix are hard to be accessed and the template molecules cannot be extracted totally. But here we propose a low crosslinked system with high specificity and selectivity. The imprinted and non-imprinted polymers were characterized by various spectroscopic techniques. The extent of binding was followed by batch equilibration method and compared with the respective non-imprinted polymer. Conditions for maximum specific rebinding were set by altering certain factors like template/monomer ratio, concentration of template solution, rebinding medium, mass of polymer and time of incubation. The selectivity of the imprinted polymer was investigated by comparing the binding with structural analogues of 2,4-D like, phenoxyacetic acid (POA), 4-chlorophenoxyacetic acid (4-CPOA) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T). The imprinted polymer exhibited high affinity towards the template molecule and was selectively rebound to the specific sites. The binding towards the structural analogues depends on the number of chlorine in the benzene ring. 展开更多
关键词 Molecular IMPRINTING 2 4-dichlorophenoxyacetic acid SPECIFICITY SELECTIVITY SEPARATION FACTOR
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Protective Effect of <i>Lepedium sativum</i>against 2, 4-Dichlorophenoxyacetic Acid Hepatotoxicity: An Electron Microscopic Study
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作者 Tahani H. Dakhakhni Gehan A. Raouf Awatef Ali 《Open Journal of Applied Sciences》 2020年第12期825-833,共9页
<div style="text-align:justify;"> <span style="font-family:Verdana;">Medicinal plants have been used to treat many diseases with fewer side effects compared to clinical medicines. The n... <div style="text-align:justify;"> <span style="font-family:Verdana;">Medicinal plants have been used to treat many diseases with fewer side effects compared to clinical medicines. The need for treatment by medicinal plants has been increasing in response to the accumulation of environmental pollutants. The herbicide 2, 4-Dichlorophenoxyacetic acid has been considered as fast spreadable environmental pollutant, which may cause many disorders in animals and possibly in humans. The aim of this study is to assess the protective and/or curative effect of </span><i><span style="font-family:Verdana;">Lepidium sativum</span></i><span style="font-family:Verdana;"> against hepatotoxicity induced by 2, 4-D herbicide in rats. 25 Albino Wistar rats were grouped into 4 groups: a control group, the curative group treated for 4 weeks with LS water extract after a single dose 2, 4-D LD</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;"> administration, protective group which was treated for 4 weeks with LS water extract prior to the 2, 4-D LD</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;"> administration, and LS only group that was given the LS water extract as a positive control. Using transmission electron microscope, the histological features showed that curative group hepatocytes still suffered from focal necrosis and vacuolation of hepatocytes as a result of 2, 4-D toxic effect whereas in the protective group hepatocytes were less accentuated expressed as less frequent necrotic area, and still large mitochondria were present with numerous undissolved lipid droplets and a small amount of rough endoplasmic reticulum. For the LS only group, nearly normal cells with centric nucleus, normal small mitochondria were at a normal nucleus-cytoplasmic ratio, but a few lipid droplets were noticed. This study proved that curative group has an advantage over the protective group that could be presented in the nucleus with narrow nuclear pores and intact nuclear envelope with dense small mitochondria and normal rough endoplasmic reticulum that were recorded as in the control group. Thus, </span><i><span style="font-family:Verdana;">Lepidium sativum </span></i><span><span style="font-family:Verdana;">administration to the rats prior or post to intoxication was effective in minimizing the 2, 4-D-induced damages likely through a free radical scavenging activity in liver tissue.</span></span> </div> 展开更多
关键词 HEPATOPROTECTIVE Toxicity Lepedium sativum 2 4-dichlorophenoxyacetic acid
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Importance of V^(4)and optimal acid environment in the hydroxylation of inert benzene via activation of C_(sp2)-H bond
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作者 Peng Dong Yang Xin +6 位作者 Yanwei Li Xiaohui Zhang Xiaorui Wang Yu Zhao Dongqiang Zhang Haowen Ma Guixian Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第10期216-226,共11页
Hydroxylation of inert benzene through the activation of the C_(sp2)-H bond is a representative reaction about the transformation of C-H bonds to C-O bonds,which has far-reaching guiding significance but remains a cha... Hydroxylation of inert benzene through the activation of the C_(sp2)-H bond is a representative reaction about the transformation of C-H bonds to C-O bonds,which has far-reaching guiding significance but remains a challenging scientific problem.To overcome this problem,a series of VOx-Ga_(2)O_(3)/SiO_(2)-Al_(2)O_(3)were prepared to achieve an efficient and economical hydroxylation path of benzene to phenol.The results showed that the phenol yield was 72.89%(selectivity>98.1%)under the optimum conditions.The reason is that the C-H bond in the benzene ring is activated by heterolysis over a VOx-Ga_(2)O_(3)/SiO_(2)-Al_(2)O_(3)catalyst.Meanwhile,the introduction of aluminum(Al)and gallium(Ga)made a qualitative change in the catalyst,enhancing the electron motion and spin motion of vanadium species,resulting in the increase of V4^(+)/V5^(+)ratio.In addition,the catalyst can provide an optimal acidic environment and a threedimensional cross-linked surface structure that facilitates product diffusion. 展开更多
关键词 C_(sp2)-H activation V4^(+)/V5^(+)ratio acid microenvironment Catalysis Support Catalyst activation
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2型糖尿病伴干眼症病人血清和泪液分泌型卷曲相关蛋白5、脂肪酸结合蛋白4水平与病情严重程度的相关性 被引量:1
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作者 张震英 田春雨 +2 位作者 赵乐 闫小艺 郑继香 《安徽医药》 CAS 2024年第1期58-63,共6页
目的分析分泌型卷曲相关蛋白5(SFRP-5)、脂肪酸结合蛋白4(FABP4)在2型糖尿病(T2DM)伴干眼症病人血清和泪液中的表达及其与病情严重程度的相关性。方法选取2020年12月至2021年12月唐山市眼科医院收治的T2DM病人145例,其中单纯T2DM病人84... 目的分析分泌型卷曲相关蛋白5(SFRP-5)、脂肪酸结合蛋白4(FABP4)在2型糖尿病(T2DM)伴干眼症病人血清和泪液中的表达及其与病情严重程度的相关性。方法选取2020年12月至2021年12月唐山市眼科医院收治的T2DM病人145例,其中单纯T2DM病人84例168眼(T2DM组),伴干眼症病人61例122眼(T2DM伴干眼症组),另选取同期该院体检健康者50例100眼作为对照组。T2DM伴干眼症病人又分为轻度组(29例)、中度组(17例)、重度组(15例)。利用酶联免疫吸附法测定所有受试者血清和泪液中SFRP-5、FABP4水平;相关性分析采用Pearson法或Spearman法;logistic回归分析影响T2DM病人干眼症发生的因素。结果T2DM伴干眼症组、T2DM组血清和泪液SFRP-5水平均低于对照组(106.09±8.37、135.72±9.26比158.34±9.45,28.85±5.13、58.27±6.14比45.18±5.92),T2DM伴干眼症组低于T2DM组(P<0.05);T2DM伴干眼症组、T2DM组血清和泪液FABP4水平均高于对照组(70.63±6.59、58.27±6.14比45.18±5.92,15.91±3.76、10.28±3.58比7.72±3.29),T2DM伴干眼症组高于T2DM组(P<0.05)。重度组、中度组血清和泪液SFRP-5水平(68.29±7.15、95.54±8.34比131.82±9.02,12.83±4.62、24.72±5.49比39.56±5.18)、泪膜破裂时间(BUT)、泪液分泌试验(SIT)低于轻度组,重度组低于中度组(P<0.05);重度组、中度组血清和泪液FABP4水平(84.56±6.83、73.18±6.94比61.93±6.27,25.64±4.19、17.15±3.86比10.16±3.47)及眼表疾病指数量表(OSDI)积分高于轻度组,重度组高于中度组(P<0.05)。T2DM伴干眼症病人血清与泪液SFRP-5水平呈正相关,血清与泪液FABP4水平也呈正相关(P<0.05)。T2DM伴干眼症病人血清和泪液SFRP-5水平与OSDI积分均呈负相关,与BUT、SIT均呈正相关(P<0.05);血清和泪液FABP4水平与OSDI积分均呈正相关,与BUT、SIT均呈负相关(P<0.05)。血清和泪液SFRP-5水平是影响T2DM病人干眼症发生的独立保护因素,而血清和泪液FABP4水平是独立危险因素(P<0.05)。结论SFRP-5在T2DM伴干眼症病人血清和泪液中均低表达,FABP4均高表达,二者与病情严重程度密切相关。 展开更多
关键词 糖尿病 2 糖尿病并发症 干眼病 血清 眼泪 分泌型卷曲相关蛋白5 脂肪酸结合蛋白4 病情严重程度
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Ni/ZrO_(2)-SO_(4)^(2-)催化剂的制备及其催化甲烷与CO_(2)制乙酸性能
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作者 任行涛 吴俊 +3 位作者 贾志光 丁靖 万辉 管国锋 《石油化工》 CAS CSCD 北大核心 2024年第4期489-495,共7页
以Zr(NO_(3))4·5H_(2)O和Ni(NO_(3))2·6H_(2)O为原料、(NH4)2CO_(3)为沉淀剂,采用溶胶凝胶-硫酸酸化两步法制备了Ni/ZrO_(2)-SO_(4)^(2-)催化剂,采用XRD,FTIR,SEM,N_(2)吸附-脱附,H_(2)-TPR,NH3-TPD等方法对Ni/ZrO_(2)-SO_(4)... 以Zr(NO_(3))4·5H_(2)O和Ni(NO_(3))2·6H_(2)O为原料、(NH4)2CO_(3)为沉淀剂,采用溶胶凝胶-硫酸酸化两步法制备了Ni/ZrO_(2)-SO_(4)^(2-)催化剂,采用XRD,FTIR,SEM,N_(2)吸附-脱附,H_(2)-TPR,NH3-TPD等方法对Ni/ZrO_(2)-SO_(4)^(2-)催化剂进行表征,考察了Ni的引入方式对催化剂的结构和性能的影响。实验结果表明,与共沉淀方式引入Ni制备的Ni/ZrO_(2)-SO_(4)^(2-)催化剂相比,采用溶胶凝胶方式引入Ni制备的催化剂的四方相ZrO_(2)占比更高,表面酸量更多,且具有良好的热稳定性和较强的L酸性;采用溶胶凝胶方式引入Ni制备的Ni/ZrO_(2)-SO_(4)^(2-)催化剂的乙酸生成量明显优于共沉淀方式引入Ni制备的Ni/ZrO_(2)-SO_(4)^(2-)催化剂。四方相ZrO_(2)、酸性位点和过渡金属Ni之间的协同作用促进了甲烷与CO_(2)直接反应合成乙酸。 展开更多
关键词 Ni/ZrO_(2)-SO_(4)^(2-) 溶胶-凝胶法 甲烷 乙酸 合成
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新标09CrCuSb耐酸钢的耐50%H_(2)SO_(4)腐蚀性能
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作者 郑健 张佳伟 +3 位作者 袁渊 张成元 黄峰 刘静 《腐蚀与防护》 CAS CSCD 北大核心 2024年第4期8-13,共6页
通过电化学测试和全浸腐蚀试验,研究了不同温度(25,50,60,70℃)条件下新标09CrCuSb耐酸钢在50%H_(2)SO_(4)溶液中的腐蚀行为。结果表明:随着温度从25℃升至70℃,新标09CrCuSb钢的腐蚀速率整体呈现增大趋势,在70℃时,腐蚀速率达到最高,为... 通过电化学测试和全浸腐蚀试验,研究了不同温度(25,50,60,70℃)条件下新标09CrCuSb耐酸钢在50%H_(2)SO_(4)溶液中的腐蚀行为。结果表明:随着温度从25℃升至70℃,新标09CrCuSb钢的腐蚀速率整体呈现增大趋势,在70℃时,腐蚀速率达到最高,为2.70 g/(m^(2)·h),这与随温度升高,腐蚀产物中具有保护性作用的Fe_(3)O_(4)含量减少,无保护作用的FeSO_(4)·H_(2)O含量增加以及锈层中微孔变化有关。另外,由于新标调整了09CrCuSb钢中Cu、Mo、Sn、Sb、W等元素的含量,与旧标09CrCuSb钢相比,阳极维钝电流密度J维钝降低,同等温度条件下,新标09CrCuSb钢的耐蚀性得到较大改善。 展开更多
关键词 新标09CrCuSb耐酸钢 50%H_(2)SO_(4)溶液 腐蚀 温度影响
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视网膜静脉阻塞患者血清FABP4,VWF和LCN-2水平表达与继发黄斑水肿程度及预后的关系研究
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作者 郑博 杜蕊 《现代检验医学杂志》 CAS 2024年第5期168-172,178,共6页
目的 探究视网膜静脉阻塞(retinal vein obstruction,RVO)患者血清脂肪细胞型脂肪酸结合蛋白(fatty acid-binding protein 4,FABP4)、血管性假血友病因子(von willebrand factor,VWF)、脂质运载蛋白2(lipocalin-2,LCN-2)水平表达与继发... 目的 探究视网膜静脉阻塞(retinal vein obstruction,RVO)患者血清脂肪细胞型脂肪酸结合蛋白(fatty acid-binding protein 4,FABP4)、血管性假血友病因子(von willebrand factor,VWF)、脂质运载蛋白2(lipocalin-2,LCN-2)水平表达与继发黄斑水肿(macular edema,ME)程度及预后的关系研究。方法 选取2021年1月~2023年8月来西北大学附属第一医院治疗的98例确诊的RVO继发ME患者为观察组,根据黄斑水肿程度分为重度组(n=46)、中度组(n=32)和轻度组(n=20),根据预后情况分为预后不良组(n=36)和预后良好组(n=62);另选取98例单纯RVO患者为对照组。比较各组血清FABP4,VWF,LCN-2水平;多因素Logistic回归分析RVO继发ME患者发生预后不良的影响因素;ROC曲线分析血清FABP4,VWF和LCN-2水平对RVO继发ME患者发生预后不良的预测价值。结果 与对照组相比,观察组血清FABP4(35.24±4.43 ng/ml vs 23.19±3.69 ng/ml),VWF(2.67±0.67 ng/ml vs1.48±0.38 ng/ml),LCN-2(112.53±12.74 mg/L vs 85.49±9.86 mg/L)水平明显升高,差异具有统计学意义(t=20.690,15.294,16.616,均P<0.05);随病情逐渐发展,轻、中、重度组血清FABP4(33.38±4.29 ng/ml,35.79±4.49 ng/ml,38.64±4.65 ng/ml),VWF(2.36±0.59 ng/ml,2.72±0.66 ng/ml,3.29±0.87 ng/ml),LCN-2(105.84±12.24 mg/L,114.61±12.88 mg/L,124.59±13.69 mg/L)水平逐渐升高,差异具有统计学意义(F=10.194,13.294,15.703,均P<0.05);与预后良好组相比,预后不良组血清FABP4(39.64±4.59 ng/ml vs 32.69±4.34 ng/ml),VWF(3.26±0.87ng/ml vs 2.33±0.55 ng/ml),LCN-2(124.56±13.42 mg/L vs 105.54±12.34 mg/L)水平明显升高,差异具有统计学意义(t=7.482,6.487,7.122,均P<0.05));血清FABP4(OR=2.236,95%CI:1.109~4.510),VWF(OR=2.069,95%CI:1.044~4.100),LCN-2(OR=1.875,95%CI:1.015~3.463)为RVO继发ME患者发生预后不良的独立危险因素(均P<0.05);血清FABP4,VWF,LCN-2水平预测患者发生预后不良的AUC(95%CI)分别为0.817(0.726~0.888),0.791(0.697~0.867)和0.798(0.705~0.872),三者联合预测的AUC为0.932(0.863~0.973),三者联合预测优于各因子单独预测(Z=2.034,2.375,2.385,P=0.042,0.018,0.017)。结论 RVO继发ME患者血清FABP4,VWF和LCN-2水平均上调,且均为患者发生预后不良的独立危险因素,三者联合检测对RVO继发ME患者发生预后不良具有更高的预测价值。 展开更多
关键词 视网膜静脉阻塞 脂肪细胞型脂肪酸结合蛋白 血管性假血友病因子 脂质运载蛋白2 黄斑水肿
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脂肪酸结合蛋白4在2型糖尿病肾病中的诊断价值
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作者 赵小芹 黄萍 +3 位作者 王鑫蕾 孙燚 王心薇 顾云娟 《南通大学学报(医学版)》 2024年第1期6-10,共5页
目的:探讨2型糖尿病(type 2 diabetes mellitus,T2DM)患者血清脂肪酸结合蛋白4(fatty acid-binding protein 4,FABP4)与糖尿病肾病(diabetic nephropathy,DN)的相关性及其作为DN早期诊断的应用价值。方法:纳入T2DM患者218例及健康体检者... 目的:探讨2型糖尿病(type 2 diabetes mellitus,T2DM)患者血清脂肪酸结合蛋白4(fatty acid-binding protein 4,FABP4)与糖尿病肾病(diabetic nephropathy,DN)的相关性及其作为DN早期诊断的应用价值。方法:纳入T2DM患者218例及健康体检者(对照组)20名,收集受试者的一般临床资料如身高、体质量、腰围、糖尿病病程等,计算BMI;收集血糖、糖化血红蛋白、空腹胰岛素、空腹C肽、肝肾功能、血脂等指标,计算稳态模型胰岛素抵抗指数(homeostasis model assessment-insulin resistance index,HOMA-IR)。采用ELISA测定血清FABP4水平;采用联合血肌酐(serum creatinine,Scr)和胱抑素C(cystatin C,Cys C)的慢性肾脏病流行病学协作方程式计算肾小球滤过率;测定尿白蛋白和肌酐水平,计算尿微量蛋白与肌酐比值(urinary albumin to creatinine ratio,UACR)。根据估算的肾小球滤过率(estimated glomerular filtration rate,eGFR)水平将T2DM患者分为肾功能正常组(eGFR≥90 mL/min/1.73 m^(2))、轻度肾功能不全组(eGFR 60~<90 mL/min/1.73 m^(2))和中度肾功能不全组(eGFR 30~<60 mL/min/1.73 m^(2));根据UACR水平分为正常蛋白尿组(UACR<30 mg/g)、微量蛋白尿组(UACR 30~<300 mg/g)和大量蛋白尿组(UACR≥300 mg/g)。采用回归分析评估FABP4与eGFR、UACR严重程度的相关性。结果:(1)与对照组相比,T2DM患者的血清FABP4显著升高。(2)在根据eGFR分层的3个亚组中,随着eGFR的下降,血清FABP4水平显著增加(P<0.001)。但在UACR亚组中差异无统计学意义(P=0.382)。(3)Spearman相关分析显示FABP4与eGFR呈负相关(r=-0.203,P=0.001),与UACR无相关性(r=0.130,P=0.055)。(4)多元线性回归表明,FABP4与eGFR呈独立负相关(r=-0.211,P<0.001),与UACR无相关性(r=-0.047,P=0.534)。(5)ROC曲线显示FABP4诊断DN的最佳截断值为103.9μg/L,AUC为0.745(灵敏度51.2%,特异度92.7%)。结论:T2DM患者血清FABP4水平升高与DN发生发展相关,有可能作为DN早期诊断的生物标志物。 展开更多
关键词 2型糖尿病 糖尿病肾病 脂肪酸结合蛋白4 早期诊断 生物标志物
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A 3D-QSAR Study on C-3 Substituted 4,6-Dichloroindole-2- Carboxylic Acids with Comparative Molecular Field Analysis
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作者 宋怀恩 沈建华 +1 位作者 闻韧 蒋华良 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第2期119-123,共5页
Aim and Method Comparative molecular field analysis (CoMFA), a threedimensional quantitative structure-activity relationship (3D-QSAR) method was applied to a novelseries of C-3 substituted 4, 6-dichloioindole-2-carbo... Aim and Method Comparative molecular field analysis (CoMFA), a threedimensional quantitative structure-activity relationship (3D-QSAR) method was applied to a novelseries of C-3 substituted 4, 6-dichloioindole-2-carboxylic acids to study the relationship betweentheir structure and the affinity for the glycine site of the NMDA receptor. Result Hie coefficientsof cross-validation q^2 and non cross-validation r^2 for the model established by the study are0.744 and 0.993, respectively, the value of variance ratio F is 261.343, and standard error estimate(SE) is 0.039. Conclusion These values indicate that the CoMFA model may have a good prediction forthe activity of C-3 substituted 4, 6-dichloroin-dole-2-carboxylic acids. As a consequence, thepredicted activity values of new designed compounds supports our conclusion from the model. 展开更多
关键词 3D-QSAR COMFA C-3 substituted 4 6-dichloroindole-2-caiboxylic acids NMDAreceptor
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4-叔丁基-2-(α-甲基苄基)苯酚—二-(2-乙基己基)磷酸协同体系萃取盐湖卤水中的铯
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作者 程鑫雨 时东 +6 位作者 张禹泽 彭小五 王毓萱 李丽娟 牛勇 谢绍雷 宋富根 《盐湖研究》 CAS CSCD 2024年第5期66-75,共10页
铯是重要的战略资源。溶剂萃取法因效率高、成本低、处理量大等优点被广泛应用于铯的分离提取。使用4-(叔丁基)-2-(α-甲基苄基)苯酚(t-BAMBP)萃取体系分离提取铯时会有强碱性萃取尾液产生,这使得该萃取体系的使用将面临着破坏生态、提... 铯是重要的战略资源。溶剂萃取法因效率高、成本低、处理量大等优点被广泛应用于铯的分离提取。使用4-(叔丁基)-2-(α-甲基苄基)苯酚(t-BAMBP)萃取体系分离提取铯时会有强碱性萃取尾液产生,这使得该萃取体系的使用将面临着破坏生态、提高成本等诸多困难,尤其对盐湖生态而言,更是极大的挑战。文章采用4(-叔丁基)-2(-α-甲基苄基)苯酚(t-BAMBP)/二(-2-乙基己基)磷酸(P204)协同萃取体系对盐湖卤水中低品位铯的分离提取工艺开展了研究,考察并优化了萃取、反萃工艺条件。实验结果表明,使用1 mol·L^(-1)的t-BAMBP和0.05 mol·L^(-1)的P204组成的有机相在相比为1/4的条件下三级逆流串级萃取卤水,铯的萃取率可达92.62%;使用0.5 mol·L^(-1)的盐酸在15/1相比的条件下三级逆流串级反萃铯的反萃率可达97.27%,铯浓度可初步富集至2.16 g·L^(-1)。本研究为盐湖卤水中的低品位铯的富集提供了新的工艺方法,拓展了溶剂萃取法提取分离铯的应用领域,对低品位铯资源的开发利用及保障我国战略资源安全具有重要意义。 展开更多
关键词 溶剂萃取 4-(叔丁基)-2-(α-甲基苄基)苯酚 二-(2-乙基己基)磷酸
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MnFe_(2)O_(4)@HMD纳米酶的合成及体外抗小细胞肺癌作用
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作者 何敬川 李婷婷 +2 位作者 潘晓琴 高明 阳洁 《中国药理学通报》 CAS CSCD 北大核心 2024年第11期2075-2082,共8页
目的制备MnFe_(2)O_(4)@HMD纳米酶,研究其体外抗小细胞肺癌活性。方法通过酯化反应及酰化反应合成HMD,通过共沉淀法合成MnFe_(2)O_(4),并在超声及磁力搅拌下合成MnFe_(2)O_(4)@HMD;通过FTIR、UV-vis、Zeta电位、XRD对MnFe_(2)O_(4)@HMD... 目的制备MnFe_(2)O_(4)@HMD纳米酶,研究其体外抗小细胞肺癌活性。方法通过酯化反应及酰化反应合成HMD,通过共沉淀法合成MnFe_(2)O_(4),并在超声及磁力搅拌下合成MnFe_(2)O_(4)@HMD;通过FTIR、UV-vis、Zeta电位、XRD对MnFe_(2)O_(4)@HMD进行表征;TEM及DLS评估MnFe_(2)O_(4)@HMD的形态及粒径分布;MTT法及活/死细胞染色研究MnFe_(2)O_(4)@HMD对H1688细胞活力的影响;共聚焦显微镜观察H1688细胞对MnFe_(2)O_(4)@HMD的摄取情况;DCF-HA染色法及GSH试剂盒检测MnFe_(2)O_(4)@HMD对H1688细胞ROS及GSH水平的影响;Western blot检测MnFe_(2)O_(4)@HMD对H1688细胞中凋亡相关蛋白Bax及Bcl-2表达的影响。结果成功制备MnFe_(2)O_(4)@HMD纳米酶,其Zeta电位及粒径分别为-14.57±1.81 mV、27.1 nm;MnFe_(2)O_(4)@HMD对H1688细胞具有浓度依赖性杀伤作用;H1688细胞对MnFe_(2)O_(4)@HMD具有良好的摄取行为;MnFe_(2)O_(4)@HMD可呈浓度依赖性诱导H1688细胞ROS的产生及GSH的消耗,并上调H1688细胞促凋亡蛋白Bax、下调抗凋亡蛋白Bcl-2的表达。结论MnFe_(2)O_(4)@HMD对H1688细胞具有良好的杀伤作用,可导致ROS的升高及GSH的消耗,并诱导H1688细胞发生凋亡。 展开更多
关键词 MnFe_(2)O_(4) 纳米酶 小细胞肺癌 透明质酸 肿瘤靶向 凋亡 ROS
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介孔片层Ni_(2)FeS_(4)纳米结构修饰电极对尿酸的电催化研究
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作者 白思奇 吕仁江 +1 位作者 高立娣 秦世丽 《化学世界》 CAS 2024年第5期305-311,共7页
以硝酸镍、硝酸铁为金属源,硫代乙酰胺为硫源,以聚环氧乙烷-聚环氧丙烷-聚环氧乙烷三嵌段共聚物(P123)为导向剂,与致孔剂的在不同金属比下用软模板法合成了介孔Ni_(2)FeS_(4)纳米片,在玻碳电极(GCE)上成膜构成尿酸传感器,通过循环伏安法... 以硝酸镍、硝酸铁为金属源,硫代乙酰胺为硫源,以聚环氧乙烷-聚环氧丙烷-聚环氧乙烷三嵌段共聚物(P123)为导向剂,与致孔剂的在不同金属比下用软模板法合成了介孔Ni_(2)FeS_(4)纳米片,在玻碳电极(GCE)上成膜构成尿酸传感器,通过循环伏安法(CV)、电流时间法(I-t)和差分脉冲伏安法(DPV)检测了修饰电极对尿酸的电催化性能,并将其应用于血清中的尿酸检测。探究了Ni_(2)FeS_(4)支持电解液的pH值及扫描速率的与峰电流的关系,研究结果表明,在最优条件下合成并修饰的电极对尿酸有较高的电化学活性、良好的选择性、稳定性和重现性,其线性范围和检出限分别为3~300和0.55μmol/L,用此方法对血清中的目标物进行测定,回收率为95.2%~103.8%。 展开更多
关键词 介孔纳米片 Ni_(2)FeS_(4) 修饰电极 尿酸 电催化
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4-氯氯苄在CO_(2)下电还原为对氯苯乙酸机制研究
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作者 董文慧 金葆康 《安徽大学学报(自然科学版)》 CAS 北大核心 2024年第3期75-83,共9页
对氯苯乙酸在生活生产中有重要应用,到目前为止,大多数合成方法都有烦琐的步骤或使用各种重金属催化剂,成本高且有污染.笔者提出一种在CO_(2)存在下,电化学还原4-氯氯苄制备高价值对氯苯乙酸化合物的方法,同时实现温室气体CO_(2)的利用... 对氯苯乙酸在生活生产中有重要应用,到目前为止,大多数合成方法都有烦琐的步骤或使用各种重金属催化剂,成本高且有污染.笔者提出一种在CO_(2)存在下,电化学还原4-氯氯苄制备高价值对氯苯乙酸化合物的方法,同时实现温室气体CO_(2)的利用与转化.采用4-氯氯苄在含电解质四乙基四氟硼酸铵的乙腈溶剂中恒电位电解合成对氯苯乙酸,电解产物经过核磁、质谱等表征方式确认结构.结果表明,法拉第电解效率为94.0%,转化率为92.9%.利用循环伏安法和原位FT-IR光谱电化学相结合的方法,探究了电化学还原制备对氯苯乙酸的电子转移机制.发现银电极上,CO_(2)气氛下4-氯氯苄的还原过程机制为两电子的不可逆过程,生成的一价阴离子随后进攻CO_(2)生成对氯苯乙酸. 展开更多
关键词 4-氯氯苄 对氯苯乙酸 CO_(2)捕获 现场红外光谱电化学 循环伏安法 电化学还原
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铬铁矿在HCl-Na_(2)CrO_(4)体系中的多级浸出动力学研究
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作者 蹇成宗 田仪娟 +3 位作者 蒋子文 闫春宇 全学军 李纲 《湿法冶金》 CAS 北大核心 2024年第4期407-419,共13页
研究了在HCl-Na_(2)CrO_(4)体系中对铬铁矿进行多级浸出,并探讨了铬铁矿中主要金属元素的浸出动力学。结果表明:在粒径45~75μm、氧化剂Na_(2)CrO_(4)用量为理论量0.6倍、反应时间5h、反应温度453.15K、料球质量比1/1、搅拌速度30r/min... 研究了在HCl-Na_(2)CrO_(4)体系中对铬铁矿进行多级浸出,并探讨了铬铁矿中主要金属元素的浸出动力学。结果表明:在粒径45~75μm、氧化剂Na_(2)CrO_(4)用量为理论量0.6倍、反应时间5h、反应温度453.15K、料球质量比1/1、搅拌速度30r/min、液固体积质量比4mL/1g最佳条件下进行3级循环浸出,铬、铁、铝、镁浸出率分别可达91.98%、94.54%、76.62%和78.03%;铬铁矿的酸浸反应受界面化学反应控制,温度在373.15~473.15K范围内,铬、铁、铝、镁的浸出表观活化能分别为45.80、40.43、42.08和43.54kJ/mol,浸出效果较好。 展开更多
关键词 铬铁矿 铬渣 盐酸 Na_(2)CrO_(4) 浸出 多级 动力学
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Highly efficient synthesis of 2,3-dihydroquinazolin-4(1H)-ones catalyzed by heteropoly acids in water 被引量:6
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作者 YingXiao Zong Yan Zhao +3 位作者 WenCai Luo Xing Hai Yu Jun Ke Wang Yi Pan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第7期778-781,共4页
Heteropoly acids efficiently catalyzed the cyclocondensation reaction of anthranilamide with aldehydes in water at ambient temperature and afforded the corresponding 2,3-dihydro-4(1H)-quinazolinones compounds in goo... Heteropoly acids efficiently catalyzed the cyclocondensation reaction of anthranilamide with aldehydes in water at ambient temperature and afforded the corresponding 2,3-dihydro-4(1H)-quinazolinones compounds in good to excellent yields.This method provides mild reaction conditions and clean reaction profiles,using a small quantity of catalyst and a simple workup procedure. 展开更多
关键词 Heteropoly acid 2 3-Dihydroquinazolin-4(1H)-ones WATER
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Hydrothermal Syntheses and Crystal Structures of Six Complexes Constructed from 1,3,5-Benzenetricarboxylic Acid and 4'-(4-Pyridyl)-2,2':6',2''-terpyridine Mixed Ligands 被引量:4
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作者 乔宇 王炫博 +4 位作者 周艳凤 刘力辉 车广波 刘春波 刘晓腾 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1381-1394,共14页
Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTP... Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTPY)(H2O)]n·2nH2O(5), and [Co(HBTC)(PYTPY)(H2O)2](6),(H3BTC = 1,3,5-benzenetricarboxylic acid, PYTPY = 4'-(4-pyridyl)-2,2':6',2''-terpyridine, DMF = N,N?-dimethylformamide), have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Complexes 1~5 all feature one-dimensional chain structures, and complex 6 exhibits a zero-dimensional structure. Complexes 1~5 present three-dimensional(3D) supramolecular frameworks via π-π stacking interactions, whenas 6 has also a 3D supramolecular structure assembled by hydrogen bonding. Meanwhile, complexes 1 ~ 6 exhibit the thermal stabilities and photoluminescent properties. 展开更多
关键词 transition metal complex 1 3 5-benzenetricarboxylic acid 4'-(4-pyridyl)-2 2' 6' 2''-terpyridine crystal structure
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Metal-directed Assembly of Two Distinct Coordination Polymers with 2,5-Furandicarboxylic Acid and 4,4'-Bipyridine 被引量:3
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作者 王浩 邢光建 +2 位作者 陈飞 孙杰 章应辉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第7期1113-1120,共8页
By using solvothermal method, two new metal coordination polymers based on 2,5-furandicarboxylic acid(H2FDA) ligand and 4,4'-bipyridine(bipy), [Cu(FDA)(4,4'-bipy)(DMF)]n·solvent(1) and {[Zn(4,4'-b... By using solvothermal method, two new metal coordination polymers based on 2,5-furandicarboxylic acid(H2FDA) ligand and 4,4'-bipyridine(bipy), [Cu(FDA)(4,4'-bipy)(DMF)]n·solvent(1) and {[Zn(4,4'-bipy)(FDA)(DMF)]·DMF}n(2), were produced and characterized by single-crystal X-ray diffraction analyses, elemental analyses, IR and powder X-ray diffraction. Compound 1 crystallizes in monoclinic space group P21/c with a = 11.104(2), b = 10.396(2), c = 18.772(4) , β = 96.20(3)o, V = 2154.2(7) 3, Dc = 1.378 g/cm^3, C19H17 Cu N3O6, Mr = 446.90, F(000) = 916, μ(Mo Kα) = 1.05 mm^-1, Z = 4, R = 0.0691 and wR = 0.1341 for 3537 observed reflections(I 2σ(I)), and R = 0.1062 and w R = 0.1482 for all data. Compound 2 crystallizes in monoclinic space group C2/c with a = 29.779(6), b = 9.6417(19), c = 17.292(3), β = 105.69(3)°, V = 4779.9(16) 3, Dc = 1.445 g/cm^3, C22H22N4O7 Zn, Mr = 519.81, F(000) = 2144, μ(Mo Kα)= 1.08 mm^-1, Z = 8, R = 0.0641 and w R = 0.1007 for 2985 observed reflections(I 2σ(I)), and R = 0.1028 and w R = 0.1112 for all data. Different coordination geometry of metal ions, square pyramid of Cu2+ and trigonal bipyramid of Zn2+, bring about different orientations of FDA2- ligands as well as 4,4'-bipyridine ligands, and furthermore distinct assembly structures for 1 and 2. The thermal stabilities of 1 and 2 are also investigated. 展开更多
关键词 2 5-furandicarboxylic acid 4 4'-bipyridine metal-directed coordination polymer
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高效液相色谱法测定2-(4-硝基苯基)丁酸有关物质
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作者 孙孝丽 姜明明 +4 位作者 杜国辉 李素敏 周娟 孙迎基 李铁军 《食品与药品》 CAS 2024年第6期557-560,共4页
目的建立2-(4-硝基苯基)丁酸中有关物质的高效液相色谱(HPLC)检测方法。方法用十八烷基硅烷键合硅胶为填充剂[推荐使用Agilent Infinity Lab Poroshell 120 EC-C_(18)(4.6 mm×250 mm,4μm)或效能相当的色谱柱];以水(用磷酸调节pH值... 目的建立2-(4-硝基苯基)丁酸中有关物质的高效液相色谱(HPLC)检测方法。方法用十八烷基硅烷键合硅胶为填充剂[推荐使用Agilent Infinity Lab Poroshell 120 EC-C_(18)(4.6 mm×250 mm,4μm)或效能相当的色谱柱];以水(用磷酸调节pH值至2.5)-乙腈(90:10)为流动相A,以水-乙腈(10:90)为流动相B,梯度洗脱;流速为1.0 ml/min;柱温为30℃;检测波长为215 nm;进样体积10μl。结果2-(4-硝基苯基)丁酸及其10个杂质在一定的范围内线性关系良好;杂质i-8与2-(4-硝基苯基)丁酸的分离度大于1.2,其他各成分峰之间的分离度均大于1.5;各成分的检出限在0.02~0.07μg/ml内;精密度试验中各杂质含量回收率RSD均不高于6%;各杂质的回收率均在92.17%~106.40%范围内;供试品溶液室温条件下放置27.5 h内有关物质没有明显变化;更换色谱柱、改变柱温、流速、流动相的pH和流动相的初始比例,有关物质的检测结果无明显变化。结论该方法专属性强,灵敏度高,可用于2-(4-硝基苯基)丁酸中有关物质的检测。 展开更多
关键词 2-(4-硝基苯基)丁酸 高效液相色谱 有关物质
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Efficacy of Topical versus Oral 5-Aminosalicylate for Treatment of 2,4,6-Trinitrobenzene Sulfonic Acid-induced Ulcerative Colitis in Rats 被引量:3
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作者 李进 陈成 +3 位作者 曹小年 王桂华 胡俊波 王晶 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第1期59-65,共7页
5-aminosalicylic acid(5-ASA) is drug of choice for the treatment of ulcerative colitis(UC). In this study, the efficacy of topical versus oral 5-ASA for the treatment of UC was examined as well as the action mecha... 5-aminosalicylic acid(5-ASA) is drug of choice for the treatment of ulcerative colitis(UC). In this study, the efficacy of topical versus oral 5-ASA for the treatment of UC was examined as well as the action mechanism of this medication. A flexible tube was inserted into the rat cecum to establish a topical administration model of 2,4,6-trinitrobenzene sulfonic acid(TNBS)-induced UC. A total of 60 rats were divided into sham operation group(receiving an enema of 0.9% saline solution instead of the TNBS solution via the tube), model group, topical 5-ASA group, oral Etiasa group(a release agent of mesalazine used as positive control) and oral 5-ASA group(n=12 each). Different treatments were administered 1 day after UC induction. The normal saline(2 mL) was instilled twice a day through the tube in the sham operation group and model group. 5-ASA was given via the tube in the topical 5-ASA group(7.5 g/L, twice per day, 100 mg/kg), and rats in the oral Etiasa group and oral 5-ASA group intragastrically received Etiasa(7.5 g/L, twice per day, 100 mg/kg) and 5-ASA(7.5 g/L, twice per day, 100 mg/kg), respectively. The body weight was recorded every day. After 7 days of treatment, blood samples were drawn from the heart to harvest the sera. Colonic tissues were separated and prepared for pathological and related molecular biological examinations. The concentrations of 5-ASA were detected at different time points in the colonic tissues, feces and sera in different groups by using the high pressure liquid chromatography(HPLC). The results showed that the symptoms of acute UC, including bloody diarrhea and weight loss, were significantly improved in topical 5-ASA-treated rats. The colonic mucosal damage, both macroscopical and histological, was significantly relieved and the myeloperoxidase activity was markedly decreased in rats topically treated with 5-ASA compared with those treated with oral 5-ASA or Etiasa. The mRNA and protein expression of IL-1β, IL-6, and TNF-α was down-regulated in the colonic tissue of rats topically treated with 5-ASA, significantly lower than those from rats treated with oral 5-ASA or Etiasa. The concentrations of 5-ASA in the colonic tissue were significantly higher in the topical 5-ASA group than in the oral 5-ASA and oral Etiasa groups. It was concluded that the topical administration of 5-ASA can effectively increase the concentration of 5-ASA in the colonic tissue, decrease the expression of proinflammatory cytokines, alleviate the colonic pathological damage and improve the symptoms of TNBS-induced acute UC in rats. 展开更多
关键词 ulcerative colitis 5-aminosalicylic acid 2 4 6-trinitrobenzene sulfonic acid
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Three New Zn(Ⅱ)/Cd(Ⅱ) Coordination Polymers Constructed with 2-Mercaptonicotinic Acid and 1,2-Di(4-pyridyl)ethylene: Syntheses and Structure Analysis 被引量:4
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作者 杨鑫 傅瑞标 +3 位作者 胡胜民 黄艺辉 盛天录 吴新涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第1期23-32,共10页
Three new Zn(Ⅱ)/Cd(Ⅱ) coordination polymers based on 2-mercaptonicotinic acid (H2mna) with 1,2-di(4-pyridyl)ethylene (dpe) introduced as a bridging ligand have been synthesized via hydrothermal method and ... Three new Zn(Ⅱ)/Cd(Ⅱ) coordination polymers based on 2-mercaptonicotinic acid (H2mna) with 1,2-di(4-pyridyl)ethylene (dpe) introduced as a bridging ligand have been synthesized via hydrothermal method and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis and IR. As reported in this paper, [Zn2(dpe)0.5(mna)2] (1) can be classified as a two-dimensional layer structure in which the 1D chain composed of Zn(Ⅱ) and mna ligands is bridged by dpe ligands, while the complex named [Zn4(dpe)4(mna)4] (2) is a tetra-nuclear cluster compound. These two compounds are further extended to three-dimensional structures by hydrogen bonds along with C–H…π and π…π interactions. Compound 3 with general formular [Cd2(dpe)0.5(mna)2]·H2O belongs to a three-dimensional porous structure in which the 2D metal layers formed by the coordination of Cd(Ⅱ) and mna ligands are connected with the bridging of dpe ligands. 展开更多
关键词 2-mercaptonicotinic acid (H2mna) 1 2-di(4-pyridyl)ethylene (dpe) zinc cadmium
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