In this contribution,we report the cooperative structure-directing effect of choline hydroxide and aluminosilicate*BEA zeolite in the synthesis of aluminogermanosilicate IWR zeolites for the first time.*BEA zeolites,a...In this contribution,we report the cooperative structure-directing effect of choline hydroxide and aluminosilicate*BEA zeolite in the synthesis of aluminogermanosilicate IWR zeolites for the first time.*BEA zeolites,at variance with any other aluminosilicate zeolites,can serve as heterogeneous seeds for the growth of IWR zeolites and play a cooperative structure-directing role.The crystallization process was investigated using multiple techniques to characterize a series of solid products obtained with various crystallization times.The experiments clearly showed the dissolution of the*BEA zeolite and of an intermediate CDO-type structure.A plausible mechanism for the novel cooperative synthesis has been proposed.The crystallization of the IWR zeolite involves several steps,among which the crucial one is believed to be the reassembly of the building units produced from the decomposition of*BEA zeolite seeds,induced by choline molecules.Having similar structure and common building units(four-,five-,and six-membered rings)with the IWR zeolite,the*BEA zeolite is capable of promoting the reassembly of the building units and can thus play a cooperative structure-directing role.By highlighting the cooperative structure-directing effect of organic molecules and heterogeneous seeds,this study opens up new perspectives for the synthesis of target zeolites that are difficult to prepare by traditional methods.This new synthetic route is also expected to shed light on the discovery of novel zeolites.展开更多
Ce/BEA has the potential to be applied as a novel passive NO_(x)absorber(PNA)in the after-treatment of vehicles due to its considerable NO_(x)storage capacity.However,as a vehicle exhaust after-treatment material,it m...Ce/BEA has the potential to be applied as a novel passive NO_(x)absorber(PNA)in the after-treatment of vehicles due to its considerable NO_(x)storage capacity.However,as a vehicle exhaust after-treatment material,it must withstand the test of long-term hydrothermal aging.This work examined the deactivation mechanism of Ce/BEA during hydrothermal aging.3.0 wt%Ce/BEA was prepared using the ionexchange method,and then subjected to hydrothermal treatment at 650℃with 10%H_(2)O for 1-12 h to obtain samples with different aging extent.For comparison,the H-BEA support was aged under the same conditions.Brunauer-Emmett-Teller(BET)method,X-ray diffraction(XRD),NH_(3)temperature programmed reduction(NH_(3)-TPD),^(27)Al MAS nuclear magnetic resonance(^(27)Al MAS NMR),H_(2)temperature programmed reduction(H_(2)-TPR),and high resolution-transmission electron microscopy(HR-TEM)were performed to characterize the changes in PNA performance,structure,Ce species,and acidity.The HR-TEM and H_(2)-TPR results show that CeO_(x)particles appear after hydrothermal aging,which results from the detachment and aggregation of active Ce species.Based on the^(27)Al MAS NMR results,we conclude that BEA zeolite dealumination leads to the loss of acidic sites and the transformation of active Ce species on the acidic sites into the less active CeO_(x).This is the primary reason for the hydrothermal aging deactivation of Ce/BEA.展开更多
Ce/BEA has great potential as a passive NO_(x)absorber(PNA)to reduce the NO_(x)emissions during the cold start phase especially in diesel engine for its high resistance to CO and suitable NO_(x)desorption temperature ...Ce/BEA has great potential as a passive NO_(x)absorber(PNA)to reduce the NO_(x)emissions during the cold start phase especially in diesel engine for its high resistance to CO and suitable NO_(x)desorption temperature range.However,as a novel material,its physical and chemical properties still remain unknown.In this work,Ce/BEA was synthesized by ion-exchange method to identify the active species in NO_(x)adsorption,compared with aggregated Ce species in Ce/SiAlO_(x) prepared by impregnation method.X-ray diffraction(XRD),high resolution-transmission electron microscopy(HR-TEM)and aberration-corrected-scanning transmission electron microscopy(AC-STEM)were performed to confirm the isolated single atom formation of Ce species in Ce/BEA.UV-vis diffraction reflection spectra(DRS)and X-ray photoelectron spectroscopy(XPS)were conducted to find the difference of chemical environment between the isolated Ce species and aggregated ones.PNA performance evaluation and temperature programmed reduction of hydrogen(H_(2)-TPR)results show the high NO_(x)storage capacity and active oxygen species quantity in Ce/BEA.It is also found that the main NO_(x)adsorption species are Ce^(4+)-O^(∗)rather than Ce^(3+).NO_(x)-diffuse reflectance infrared Fourier transform spectroscopy(NO_(x)-DRIFTS)confirms that the bidentate nitrite species are the critical NO_(x)adsorption intermediates and the conception of NO_(x)adsorption and desorption processes is proposed.展开更多
目的:研究丁酸钠、曲古抑菌素A(trichostatin A,TSA)及腺病毒E1A相关的300 kD蛋白(adenoviral E1A binding protein of 300 kD,P300)介导的组蛋白乙酰化在人非小细胞肺癌A549细胞及人支气管上皮BEAS-2B细胞中对哮喘易感的解整合素金属...目的:研究丁酸钠、曲古抑菌素A(trichostatin A,TSA)及腺病毒E1A相关的300 kD蛋白(adenoviral E1A binding protein of 300 kD,P300)介导的组蛋白乙酰化在人非小细胞肺癌A549细胞及人支气管上皮BEAS-2B细胞中对哮喘易感的解整合素金属蛋白酶33(a disintegrin and metalloproteinase 33,ADAM33)基因表达的影响。方法:将A549细胞及BEAS-2B细胞分别分为丁酸钠对照组(双蒸水处理)和1、2.5、5 mmol/L丁酸钠组,TSA对照组(0.1%二甲基亚砜处理)和0.2、0.4、0.8μmol/L TSA组,按照组别分别予以相应处理;另将BEAS-2B细胞分为对照组(转染P300突变质粒)和P300组(转染P300表达质粒);采用双荧光素酶报告基因法分析ADAM33启动子活性的变化,实时荧光定量PCR(quantitative real time-PCR,qRT-PCR)检测ADAM33 mRNA表达,蛋白质印迹法检测ADAM33蛋白表达。结果:在人非小细胞肺癌A549细胞中,与对照组相比,1 mmol/L丁酸钠组及0.2μmol/L TSA组ADAM33基因启动子活性明显降低(P<0.01);在BEAS-2B细胞中,与对照组相比,1 mmol/L丁酸钠组及0.2μmol/L TSA组ADAM33基因启动子活性、mRNA及蛋白相对表达水平明显降低(P<0.05或P<0.01)。加大丁酸钠、TSA药物浓度,ADAM33表达无显著差异。在人支气管上皮BEAS-2B细胞中,与对照组相比,P300组ADAM33启动子活性、mRNA和蛋白相对表达水平明显降低(P<0.05)。结论:丁酸钠、TSA通过组蛋白乙酰化降低人非小细胞肺癌A549细胞和人支气管上皮BEAS-2B细胞中ADAM33表达,P300通过组蛋白乙酰化降低人支气管上皮BEAS-2B细胞中ADAM33表达。展开更多
目的通过离散型逼近理想解排序法(technique for order preference by similarity to an ideal solution,TOPSIS)评估6批法半夏醇提物的体外抗慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)作用,建立法半夏综合品质评...目的通过离散型逼近理想解排序法(technique for order preference by similarity to an ideal solution,TOPSIS)评估6批法半夏醇提物的体外抗慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)作用,建立法半夏综合品质评价新方法。方法采用香烟烟雾提取物(cigarette smoke extract,CSE)和脂多糖(lipopolysaccharide,LPS)构建Beas-2b人正常肺细胞的COPD模型,并使用MTT法测定生半夏及6批法半夏醇提取物的毒性和药效浓度,同时计算EC 50、IC 50;再由qRT-PCR、超氧化物歧化酶(superoxide dismutase,SOD)试剂盒测定相关指标;最后通过TOPSIS法对生半夏和法半夏进行多指标综合评价。结果根据IC 50值,得出各批次样品如下毒性排序:生半夏>法半夏④>法半夏①>法半夏⑤>法半夏③>法半夏⑥>法半夏②。通过qRT-PCR法验证得出,与模型组对比,各半夏给药组的TNF-α、IL-6和IL-8的表达均有不同程度的下调;并且在给药后所有给药组的SOD的含量均降低。将所有数据进行归一化处理,通过TOPSIS分析,得到药效综合排序结果如下:法半夏⑥>法半夏⑤>法半夏②>法半夏①>法半夏③>法半夏④>生半夏。结论不同半夏醇提物均可抑制LPS和CSE诱导的炎症和氧化应激,综合评价第⑥批法半夏的质量最好,且TOPSIS法可以作为一种药材的综合品质评定方法,为市面上参差不齐的药材质量提供质控思路。展开更多
基金supported by the National Key R&D Program of China(2017YFB0702800)National Natural Science Foundation of China(21802168,21503280,21603277)China Petrochemical Corporation(Sinopec Group)~~
文摘In this contribution,we report the cooperative structure-directing effect of choline hydroxide and aluminosilicate*BEA zeolite in the synthesis of aluminogermanosilicate IWR zeolites for the first time.*BEA zeolites,at variance with any other aluminosilicate zeolites,can serve as heterogeneous seeds for the growth of IWR zeolites and play a cooperative structure-directing role.The crystallization process was investigated using multiple techniques to characterize a series of solid products obtained with various crystallization times.The experiments clearly showed the dissolution of the*BEA zeolite and of an intermediate CDO-type structure.A plausible mechanism for the novel cooperative synthesis has been proposed.The crystallization of the IWR zeolite involves several steps,among which the crucial one is believed to be the reassembly of the building units produced from the decomposition of*BEA zeolite seeds,induced by choline molecules.Having similar structure and common building units(four-,five-,and six-membered rings)with the IWR zeolite,the*BEA zeolite is capable of promoting the reassembly of the building units and can thus play a cooperative structure-directing role.By highlighting the cooperative structure-directing effect of organic molecules and heterogeneous seeds,this study opens up new perspectives for the synthesis of target zeolites that are difficult to prepare by traditional methods.This new synthetic route is also expected to shed light on the discovery of novel zeolites.
基金supported the National Key R&D Program of China(2021YFB3503200)the Innovative Research Groups of the National Natural Science Foundation of China(51921004)+1 种基金Young Elite Scientists Sponsorship Program by CAST(2021QNRC001)the Key R&D Project of Shandong Province(2021CXGC010703,2022CXGC020311)。
文摘Ce/BEA has the potential to be applied as a novel passive NO_(x)absorber(PNA)in the after-treatment of vehicles due to its considerable NO_(x)storage capacity.However,as a vehicle exhaust after-treatment material,it must withstand the test of long-term hydrothermal aging.This work examined the deactivation mechanism of Ce/BEA during hydrothermal aging.3.0 wt%Ce/BEA was prepared using the ionexchange method,and then subjected to hydrothermal treatment at 650℃with 10%H_(2)O for 1-12 h to obtain samples with different aging extent.For comparison,the H-BEA support was aged under the same conditions.Brunauer-Emmett-Teller(BET)method,X-ray diffraction(XRD),NH_(3)temperature programmed reduction(NH_(3)-TPD),^(27)Al MAS nuclear magnetic resonance(^(27)Al MAS NMR),H_(2)temperature programmed reduction(H_(2)-TPR),and high resolution-transmission electron microscopy(HR-TEM)were performed to characterize the changes in PNA performance,structure,Ce species,and acidity.The HR-TEM and H_(2)-TPR results show that CeO_(x)particles appear after hydrothermal aging,which results from the detachment and aggregation of active Ce species.Based on the^(27)Al MAS NMR results,we conclude that BEA zeolite dealumination leads to the loss of acidic sites and the transformation of active Ce species on the acidic sites into the less active CeO_(x).This is the primary reason for the hydrothermal aging deactivation of Ce/BEA.
基金Project supported by the National Key R&D Program of China(2021YFB3503200)the Innovative Research Groups of the National Natural Science Foundation of China(51921004)+1 种基金Young Elite Scientists Sponsorship Program by CAST(2021QNRC001)the Key R&D project of Shandong Province(2021CXGC010703,2022CXGC020311)。
文摘Ce/BEA has great potential as a passive NO_(x)absorber(PNA)to reduce the NO_(x)emissions during the cold start phase especially in diesel engine for its high resistance to CO and suitable NO_(x)desorption temperature range.However,as a novel material,its physical and chemical properties still remain unknown.In this work,Ce/BEA was synthesized by ion-exchange method to identify the active species in NO_(x)adsorption,compared with aggregated Ce species in Ce/SiAlO_(x) prepared by impregnation method.X-ray diffraction(XRD),high resolution-transmission electron microscopy(HR-TEM)and aberration-corrected-scanning transmission electron microscopy(AC-STEM)were performed to confirm the isolated single atom formation of Ce species in Ce/BEA.UV-vis diffraction reflection spectra(DRS)and X-ray photoelectron spectroscopy(XPS)were conducted to find the difference of chemical environment between the isolated Ce species and aggregated ones.PNA performance evaluation and temperature programmed reduction of hydrogen(H_(2)-TPR)results show the high NO_(x)storage capacity and active oxygen species quantity in Ce/BEA.It is also found that the main NO_(x)adsorption species are Ce^(4+)-O^(∗)rather than Ce^(3+).NO_(x)-diffuse reflectance infrared Fourier transform spectroscopy(NO_(x)-DRIFTS)confirms that the bidentate nitrite species are the critical NO_(x)adsorption intermediates and the conception of NO_(x)adsorption and desorption processes is proposed.
文摘目的通过离散型逼近理想解排序法(technique for order preference by similarity to an ideal solution,TOPSIS)评估6批法半夏醇提物的体外抗慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)作用,建立法半夏综合品质评价新方法。方法采用香烟烟雾提取物(cigarette smoke extract,CSE)和脂多糖(lipopolysaccharide,LPS)构建Beas-2b人正常肺细胞的COPD模型,并使用MTT法测定生半夏及6批法半夏醇提取物的毒性和药效浓度,同时计算EC 50、IC 50;再由qRT-PCR、超氧化物歧化酶(superoxide dismutase,SOD)试剂盒测定相关指标;最后通过TOPSIS法对生半夏和法半夏进行多指标综合评价。结果根据IC 50值,得出各批次样品如下毒性排序:生半夏>法半夏④>法半夏①>法半夏⑤>法半夏③>法半夏⑥>法半夏②。通过qRT-PCR法验证得出,与模型组对比,各半夏给药组的TNF-α、IL-6和IL-8的表达均有不同程度的下调;并且在给药后所有给药组的SOD的含量均降低。将所有数据进行归一化处理,通过TOPSIS分析,得到药效综合排序结果如下:法半夏⑥>法半夏⑤>法半夏②>法半夏①>法半夏③>法半夏④>生半夏。结论不同半夏醇提物均可抑制LPS和CSE诱导的炎症和氧化应激,综合评价第⑥批法半夏的质量最好,且TOPSIS法可以作为一种药材的综合品质评定方法,为市面上参差不齐的药材质量提供质控思路。
