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Procyanidin A_1 and its digestive products alleviate acrylamide-induced IPEC-J2 cell damage through regulating Keap1/Nrf2 pathway
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作者 Fangfang Yan Qun Lu +1 位作者 Chengming Wang Rui Liu 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1475-1484,共10页
Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In thi... Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell damage.ACR slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell damage.Importantly,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR. 展开更多
关键词 Procyanidin A_1 Digestive products Acrylamide Nuclear factor erythroid 2-related factor 2(Nrf2) Intestinal cell damage
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Molecular engineering binuclear copper catalysts for selective CO_(2) reduction to C_(2) products
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作者 Qi Zhao Kai Lei +2 位作者 Bao Yu Xia Rachel Crespo-Otero Devis Di Tommaso 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期166-173,I0005,共9页
Molecular copper catalysts serve as exemplary models for correlating the structure-reaction-mechanism relationship in the electrochemical CO_(2) reduction(eCO_(2)R),owing to their adaptable environments surrounding th... Molecular copper catalysts serve as exemplary models for correlating the structure-reaction-mechanism relationship in the electrochemical CO_(2) reduction(eCO_(2)R),owing to their adaptable environments surrounding the copper metal centres.This investigation,employing density functional theory calculations,focuses on a novel family of binuclear Cu molecular catalysts.The modulation of their coordination configuration through the introduction of organic groups aims to assess their efficacy in converting CO_(2) to C_(2)products.Our findings highlight the crucial role of chemical valence state in shaping the characteristics of binuclear Cu catalysts,consequently influencing the eCO_(2)R behaviour,Notably,the Cu(Ⅱ)Cu(Ⅱ)macrocycle catalyst exhibits enhanced suppression of the hydrogen evolution reaction(HER),facilitating proton trans fer and the eCO_(2)R process.Fu rthermore,we explo re the impact of diverse electro n-withdrawing and electron-donating groups coordinated to the macrocycle(R=-F,-H,and-OCH_3)on the electron distribution in the molecular catalysts.Strategic placement of-OCH_3 groups in the macrocycles leads to a favourable oxidation state of the Cu centres and subsequent C-C coupling to form C_(2) products.This research provides fundamental insights into the design and optimization of binuclear Cu molecular catalysts for the electrochemical conversion of CO_(2) to value-added C_(2) products. 展开更多
关键词 Molecular catalyst design Selective CO_(2)reduction C_(2)products Density functional theory calculations
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Nitrogen-doping boosts ^(*)CO utilization and H_(2)O activation on copper for improving CO_(2) reduction to C_(2+) products
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作者 Yisen Yang Zhonghao Tan +5 位作者 Jianling Zhang Jie Yang Renjie Zhang Sha Wang Yi Song Zhuizhui Su 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1459-1465,共7页
To improve the electrocatalytic transformation of carbon dioxide (CO_(2)) to multi-carbon (C_(2+)) products is of great importance.Here we developed a nitrogen-doped Cu catalyst,by which the maximum C_(2+) Faradaic ef... To improve the electrocatalytic transformation of carbon dioxide (CO_(2)) to multi-carbon (C_(2+)) products is of great importance.Here we developed a nitrogen-doped Cu catalyst,by which the maximum C_(2+) Faradaic efficiency can reach 72.7%in flow-cell system,with the partial current density reaching 0.62 A cm^(-2).The in situ Raman spectra demonstrate that the *CO adsorption can be strengthened on such a N-doped Cu catalyst,thus promoting the *CO utilization in the subsequent C–C coupling step.Simultaneously,the water activation can be well enhanced by N doping on Cu catalyst.Owing to the synergistic effects,the selectivity and activity for C_(2+) products over the N-deoped Cu catalyst are much improved. 展开更多
关键词 Electrocatalytic CO_(2)reduction reaction Copper catalyst DOPING Multi-carbon products In situ Raman measurement
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A Comparative Study on Chemical Composition of Supercritical CO_2 Extraction Products in Peels of Trichosanthes kirilowii Maxim. from Changqing District
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作者 于京平 李佳 +1 位作者 张永清 范英才 《Agricultural Science & Technology》 CAS 2013年第2期257-261,共5页
[Objective] This study aimed to investigate the differences in chemical composition of supercritical CO2 extraction products in peels of Trichosanthes kirilowii Maxim. from Changqing district. [Method] Supercritical f... [Objective] This study aimed to investigate the differences in chemical composition of supercritical CO2 extraction products in peels of Trichosanthes kirilowii Maxim. from Changqing district. [Method] Supercritical fluidextraction (SFE) and GCMS method were applied to determine and analyze the chemical components of the extracts in peels of three strains of Trichosanthes kirilowii Maxim. [Result] The chemical components of supercritical CO2 extraction products in peels of three strains of Trichosanthes kirilowii Maxim. varied., and the number of chemical components with normalized percentage content higher than 1% was 5, 7 and 8, respectively. There are 14 kinds of common components, and the relative content of hexadecanoic acid was the highest. [Conclusion] Supercritical CO2 extracts in peels of different strains of Trichosanthes kirilowii Maxim. contain different chemical components, providing scientific basis for breeding excellent varieties and the development and utilization of Trichosanthes kirilowii Maxim. 展开更多
关键词 Trichosanthes kirilowii Maxim. PEEL Supercritical CO2 extraction products Chemical components COMPARISON
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胜利油田陆相页岩油前置CO_(2)压裂技术研究与实践
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作者 李阳 赵清民 +5 位作者 杨勇 张峰 曹功泽 张潦源 杨峰 鲁明晶 《断块油气田》 CAS CSCD 北大核心 2024年第6期945-954,共10页
陆相页岩油是我国油气资源重要的产量接替阵地,胜利油田济阳坳陷页岩油是我国陆相断陷盆地页岩油的典型代表,预测资源量超百亿吨,勘探开发前景广阔。但与北美海相页岩油的区别在于,济阳页岩油具有埋藏深、成熟度低等特点,压裂工艺造缝... 陆相页岩油是我国油气资源重要的产量接替阵地,胜利油田济阳坳陷页岩油是我国陆相断陷盆地页岩油的典型代表,预测资源量超百亿吨,勘探开发前景广阔。但与北美海相页岩油的区别在于,济阳页岩油具有埋藏深、成熟度低等特点,压裂工艺造缝及缝网导流面临更大挑战。前置CO_(2)压裂技术集成了CO_(2)干法压裂和常规水力压裂的优势,在强化陆相页岩油增产效果方面成效显著。以胜利油田济阳坳陷陆相页岩油为例,开展前置CO_(2)+压裂液压裂研究,通过流体高压物性实验、岩石力学实验、真三轴压裂实验和数值模拟等多种研究手段相结合,揭示了前置CO_(2)压裂过程中复杂的水/岩和多相流体作用机制,明确其在降低储层破裂压力、改善储层物性、提高储/地层能量、促进复杂缝网形成、降低储层伤害和提高页岩油流动性等方面的作用效果。在理论研究基础上,结合矿场试验,阐明了前置CO_(2)压裂在陆相页岩油高效开发中的技术优势和应用前景,总结了技术存在问题,预测了下步发展趋势,为进一步提高我国陆相页岩油开发效果、实现CO_(2)高效埋存和利用提供了指导和借鉴。 展开更多
关键词 陆相页岩油 前置CO_(2)压裂 强化改造 增产机理 济阳坳陷
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封隔器卡瓦用20CrNiMo钢和20CrMnMo钢在某油田井下工况中的腐蚀行为
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作者 董社霞 程文佳 +2 位作者 靳浩楠 赵煜龙 林学强 《腐蚀与防护》 CAS CSCD 北大核心 2024年第11期1-7,共7页
在模拟深井/超深井的高温、高压、含CO_(2)/H_(2)S环境中,对封隔器卡瓦用20CrMnMo钢和20CrNiMo钢开展腐蚀试验;利用扫描电镜(SEM)、能谱仪(EDS)、X射线衍射(XRD)、X射线光电子能谱技术(XPS)和电化学测试等方法对比研究了两种材料的腐蚀... 在模拟深井/超深井的高温、高压、含CO_(2)/H_(2)S环境中,对封隔器卡瓦用20CrMnMo钢和20CrNiMo钢开展腐蚀试验;利用扫描电镜(SEM)、能谱仪(EDS)、X射线衍射(XRD)、X射线光电子能谱技术(XPS)和电化学测试等方法对比研究了两种材料的腐蚀行为。结果表明:模拟深井/超深井工况下,20CrMnMo钢腐蚀形态为典型的全面腐蚀,而20CrNiMo钢腐蚀形态为点蚀;两种材料表面形成的腐蚀产物均呈双层结构,外层腐蚀产物均由疏松絮状FeS和颗粒状FeCO_(3)构成;20CrNiMo钢内层腐蚀产物由单一的FeCO_(3)构成,而20CrMnMo钢内层腐蚀产物除了FeCO_(3)还有少量Cr(OH)_(3),Cr(OH)_(3)的存在有效提高了该钢内层腐蚀产物膜的保护性,从而使该钢耐蚀性能明显优于20CrNiMo钢。 展开更多
关键词 封隔器卡瓦 20CrNiMo钢 20CRMNMO钢 CO_(2)/H_(2)S腐蚀 腐蚀产物特征
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不同CO_(2)压力下黄铁矿与煤制气耦合机制研究
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作者 夏大平 廖佳佳 +4 位作者 王心义 李赛赛 顾朋涛 袁筱莹 简阔 《河南理工大学学报(自然科学版)》 CAS 北大核心 2024年第3期101-106,134,共7页
目的为了研究不同CO_(2)压力下黄铁矿与煤制气的耦合机制,方法利用压力为1,3,5 MPa的高压罐进行煤和黄铁矿厌氧发酵产气试验。结果结果表明:(1)压力1 MPa时产气量较好,最终产气量为1.26 mmol/g;压力增加,罐中产气量减少,压力5 MPa时产... 目的为了研究不同CO_(2)压力下黄铁矿与煤制气的耦合机制,方法利用压力为1,3,5 MPa的高压罐进行煤和黄铁矿厌氧发酵产气试验。结果结果表明:(1)压力1 MPa时产气量较好,最终产气量为1.26 mmol/g;压力增加,罐中产气量减少,压力5 MPa时产气量仅0.02 mmol/g。(2)随着压力增加,水溶液中HCO-3质量浓度和氧化还原电位(Eh)逐渐上升,pH逐渐下降,5 MPa试验组反应末期pH最低,为4.02,1 MPa压力罐内总铁有消耗,波动较大;反应前期,3,5 MPa压力罐中总铁质量浓度持续增加,说明反应前期3,5 MPa压力下黄铁矿溶解量增加较多;(3)高压条件下,化学需氧量(chemical oxygen deman,COD)和短链脂肪酸浓度水平的显著减少反映了厌氧发酵程度的减弱和黄铁矿酸化程度的增强;(4)压力增加,功能菌种丰度和多样性降低,硫杆菌属逐渐处于优势地位,厌氧发酵过程基本停滞。结论适宜的CO_(2)压力条件可促进煤储层条件下的微生物生长代谢,同时添加黄铁矿发生氧化产生的铁离子,可促进菌群酶活,使煤生物产气反应顺利进行。研究结果可为原位条件富集营养液注入后的产气机制研究提供理论支撑。 展开更多
关键词 CO_(2)压力 煤生物产气 黄铁矿 总铁 酸化程度
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胺功能化的铜催化剂:氢键介导的电化学CO_(2)还原为C_(2)产物以及优越的可充电Zn-CO_(2)电池性能
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作者 项东 李坤振 +3 位作者 苗康华 龙冉 熊宇杰 康雄武 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第8期43-46,共4页
有机分子功能化是一种有前景的策略,用于调控电化学CO_(2)还原反应(eCO_(2)RR)的C_(2+)产物选择性和活性。然而,我们对于电化学CO_(2)还原调控机制的分子水平理解仍然不够清晰。在本文中,我们成功制备了铜纳米颗粒,并使用一系列胺类衍生... 有机分子功能化是一种有前景的策略,用于调控电化学CO_(2)还原反应(eCO_(2)RR)的C_(2+)产物选择性和活性。然而,我们对于电化学CO_(2)还原调控机制的分子水平理解仍然不够清晰。在本文中,我们成功制备了铜纳米颗粒,并使用一系列胺类衍生物(如十六胺(HAD)、N-甲基十六胺(N-MHDA)、十六烷基二甲胺(HDDMA)和十六酰胺(PMM))对其进行功能化,以系统地研究胺表面活性剂分子结构对eCO_(2)RR选择性和活性的影响。结果表明,HDA的功能化可以将C_(2)产物和C_(2)H_(4)的法拉第效率(FE)提高至73.5%和46.4%,并且在−0.9 V vs.RHE(可逆氢电极)电位下,C_(2)产物的分电流密度为131.4 mA·cm^(−2)。理论研究发现,HDA通过与CO_(2)和eCO_(2)RR中间体之间的氢键相互作用,富集了^(*)CO_(2)、^(*)CO和其他反应中间体,降低了CO―CHO耦合反应的动力学能垒,从而促进了eCO_(2)RR向C_(2)产物的转化。当胺基的H原子被甲基取代后,氢键相互作用减弱,竞争的析氢反应加剧。PMM通过Cu―O键与Cu表面发生键合,而不是通过Cu―N键,导致Cu-PMM更倾向于产乙醇。原位拉曼光谱显示,在Cu-HDA表面,CO主要吸附在Cu的顶位吸附位点上,与在Cu表面上的桥式吸附不同,这可能是因为前者表面对CO的富集引发了CO的吸附构型变化。HDA功能化还提高了Cu催化剂的表面pH。基于Cu-HDA组装的可充电Zn-CO_(2)电池在放电电流密度为16 mA∙cm^(−2)时,最大功率密度为6.48 mW∙cm^(−2),并具有长达60 h的良好充放电稳定性。本研究的重点在于通过在分子水平上调节Cu基材料的CO_(2)RR活性和选择性,促进CO_(2)-C_(2)的转化,这可能为提高C_(2)产物的产率提供新的见解。 展开更多
关键词 二氧化碳还原 CO―CHO耦合 有机分子功能化 原位拉曼 C_(2)产物 Zn-CO_(2)电池
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TiO_(2)@H^(+)/g⁃C_(3)N_(4)复合材料的光催化产氢性能及机理分析
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作者 徐宏妍 陈书航 +2 位作者 郝亚超 赵阳灿 王斯琰 《中北大学学报(自然科学版)》 CAS 2024年第2期239-246,共8页
本文研究了TiO_(2)含量对TiO_(2)@H^(+)/g-C_(3)N_(4)异质结光催化剂产氢性能的影响。首先将石墨相氮化碳(g-C_(3)N_(4))用硫酸处理,得到酸洗氮化碳(H^(+)/g-C_(3)N_(4)),然后通过煅烧法在H^(+)/g-C_(3)N_(4)表面负载TiO_(2)得到TiO_(2)... 本文研究了TiO_(2)含量对TiO_(2)@H^(+)/g-C_(3)N_(4)异质结光催化剂产氢性能的影响。首先将石墨相氮化碳(g-C_(3)N_(4))用硫酸处理,得到酸洗氮化碳(H^(+)/g-C_(3)N_(4)),然后通过煅烧法在H^(+)/g-C_(3)N_(4)表面负载TiO_(2)得到TiO_(2)@H^(+)/g-C_(3)N_(4)复合材料,利用透射电镜、X射线衍射仪、紫外-可见漫反射仪和比表面仪对TiO_(2)@H^(+)/g-C_(3)N_(4)复合材料进行了表征,研究了其在可见光下的光催化产氢性能,探讨了TiO_(2)@H^(+)/g-C_(3)N_(4)复合材料光催化产氢机理。实验结果表明:1)煅烧法可以成功制备TiO_(2)@H^(+)/g-C_(3)N_(4)复合材料,且TiO_(2)的负载显著地提升了H^(+)/g-C_(3)N_(4)的光催化产氢性能,这主要归功于TiO_(2)/g-C_(3)N_(4)异质结的形成降低了光生电子空穴的复合速率,加快了电子的转移速率;2)实验结果还表明TiO_(2)的负载量对TiO_(2)@H^(+)/g-C_(3)N_(4)复合材料的光催化产氢性能有很大影响,当TiO_(2)含量为25%时,所制备的25-TiO_(2)@H^(+)/g-C_(3)N_(4)复合材料的光催化产氢性能最好,其光催化产氢速率为3.47 mmol·g^(−1)·h^(−1),是H^(+)/g-C_(3)N_(4)产氢速率的4.05倍,这主要归功于25-TiO_(2)@H^(+)/g-C_(3)N_(4)大的比表面积和高的光吸收度;3)所制备的25-TiO_(2)@H^(+)/g-C_(3)N_(4)复合材料还表现出良好的稳定性。 展开更多
关键词 g-C_(3)N_(4) TiO_(2) 光催化产氢 异质结 煅烧
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5Cr油套管钢在含Cl^(-)的CO_(2)环境中的腐蚀特性研究
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作者 赵国仙 刘冉冉 +6 位作者 李琼玮 杨立华 孙雨来 丁浪勇 王映超 张思琦 宋洋 《表面技术》 EI CAS CSCD 北大核心 2024年第6期55-66,共12页
目的掌握油气井生产中CO_(2)腐蚀对油套管的影响规律,研究兼顾耐蚀性和经济性的5Cr油套管材料在含Cl^(-)的CO_(2)环境中不同时间下的腐蚀演变规律。方法采用XRD、XPS、SEM和EDS等技术分析5Cr油套管钢在不同时间下腐蚀产物膜的演变情况,... 目的掌握油气井生产中CO_(2)腐蚀对油套管的影响规律,研究兼顾耐蚀性和经济性的5Cr油套管材料在含Cl^(-)的CO_(2)环境中不同时间下的腐蚀演变规律。方法采用XRD、XPS、SEM和EDS等技术分析5Cr油套管钢在不同时间下腐蚀产物膜的演变情况,利用丝束电极(WBE)和阻抗测试(EIS)技术对其腐蚀电化学行为进行研究。结果5Cr油套管钢腐蚀后期的平均腐蚀速率约为初期的1/2,在腐蚀14 d后,腐蚀产物膜中的Cr富集大于30%,Cr、Fe质量比达到较高水平,约为基体的15倍。随着腐蚀的进行,电荷传递电阻和产物膜覆盖引起的电阻增大,电化学反应阻力增大。在腐蚀前期具有局部不均匀性,随着腐蚀的进行,电极腐蚀电位有负移现象,最终分布区间为−0.59~−0.61 V,电极表面阳极电流区域大幅减少。结论在腐蚀时间延长的条件下,5Cr油套管钢腐蚀产物膜的致密性增加,电荷传递电阻呈变大趋势。在产物膜下的5Cr油套管钢区域,电流发生由阴极向阳极极性转变的现象,产物膜存在的孔隙使5Cr油套管钢基体金属被腐蚀,从而导致阳极电流的出现。表面局部腐蚀电位阳极区的形成和扩展使其有产生点蚀的倾向,但腐蚀产物逐渐沉积在点蚀坑内壁,形成了Cr富集的保护性表面层,原发生点蚀区域由原阳极活性点位转变为阴极区,对其发展起到了抑制作用。 展开更多
关键词 5Cr油套管钢 CO_(2)腐蚀 腐蚀产物膜 Cr元素富集 电化学阻抗谱 丝束电极
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致密砂岩气藏稳产后期动用效果评价与动用潜力分析:以子洲气田山2气藏为例
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作者 樊志强 雷小兰 +4 位作者 李浩 李博远 代金友 陈代欣 赵世佳 《科学技术与工程》 北大核心 2024年第21期8917-8924,共8页
以子洲气田山2气藏为例,利用钻井及生产动态资料,通过对地质储量、动储量、累产气、累产水和动静储量比的计算与分析,采用综合评判指数法和类比法,详细评价了山2致密砂岩气藏动用效果和动用潜力。结果表明:山2气藏平面动用严重不均衡。... 以子洲气田山2气藏为例,利用钻井及生产动态资料,通过对地质储量、动储量、累产气、累产水和动静储量比的计算与分析,采用综合评判指数法和类比法,详细评价了山2致密砂岩气藏动用效果和动用潜力。结果表明:山2气藏平面动用严重不均衡。7个井区中,主砂体带中部的榆30井区动用效果最好,属Ⅰ类动用区;主砂体带南部的洲3和北部榆81井区动用效果中等,为Ⅱ类动用区;主砂体周边的榆69、榆48、麒麟沟和榆29井区动用效果差,属Ⅲ类动用区。初步预测山2气藏整体动用潜力为198.1×10^(8) m^(3)。其中,Ⅲ类区的动用潜力为174.7×10^(8) m^(3),占88.2%,是山2气藏后续挖潜重点。 展开更多
关键词 致密砂岩气藏 稳产后期 动用效果 动用潜力 子洲气田山2气藏
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非酒精性脂肪性肝炎患者血清Nrf2、AOPP水平与血脂、肝纤维化的关系
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作者 王鹏森 何瑛 +1 位作者 李同心 陈继德 《国际检验医学杂志》 CAS 2024年第19期2345-2348,共4页
目的探讨非酒精性脂肪性肝炎(NASH)患者血清核因子E2相关因子2(Nrf2)、晚期氧化蛋白产物(AOPP)水平与血脂、肝纤维化的关系。方法选择重庆医科大学附属璧山医院收治的104例NASH患者作为研究组,另选90例体检健康者作为对照组。检测并比... 目的探讨非酒精性脂肪性肝炎(NASH)患者血清核因子E2相关因子2(Nrf2)、晚期氧化蛋白产物(AOPP)水平与血脂、肝纤维化的关系。方法选择重庆医科大学附属璧山医院收治的104例NASH患者作为研究组,另选90例体检健康者作为对照组。检测并比较各组血清Nrf2、AOPP水平,采用Pearson或Spearman相关分析NASH患者血清Nrf2、AOPP水平与血脂、肝纤维化的关系,采用受试者工作特征(ROC)曲线评估血清Nrf2、AOPP水平对NASH的诊断价值。结果研究组甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、Nrf2、AOPP水平均高于对照组(P<0.05),高密度脂蛋白胆固醇(HDL-C)水平明显低于对照组(P<0.05)。重度组血清Nrf2、AOPP水平高于中度组、轻度组(P<0.05),中度组血清Nrf2、AOPP水平高于轻度组(P<0.05)。相关分析结果显示,NASH患者血清Nrf2、AOPP水平与TG、TC、LDL-C、肝纤维化程度均呈正相关(P<0.05),与HDL-C呈负相关(P<0.05)。血清Nrf2诊断NASH的曲线下面积(AUC)为0.830(95%CI 0.780~0.880),血清AOPP诊断NASH的AUC为0.866(95%CI 0.816~0.916),二者联合诊断NASH的AUC为0.925(95%CI 0.875~0.975)。结论NASH患者血清Nrf2、AOPP水平均升高,且二者水平与血脂、肝纤维化程度均存在密切关系,有望作为诊断NASH发生的有效指标。 展开更多
关键词 非酒精性脂肪性肝炎 核因子E2相关因子2 晚期氧化蛋白产物 血脂 肝纤维化
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La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)催化剂对NO选择性生成NH_(3)的影响
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作者 宋崇林 郑庆贺 +3 位作者 吕誉 崔立峰 李云强 吕刚 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2024年第10期1053-1061,共9页
为了实现碳中和目标,降低内燃机碳排放,稀薄燃烧技术成为了当前重要的研究方向.该技术不仅能提高发动机燃油热效率,还能有效降低CO_(2)排放.但是稀薄燃烧往往会伴随着大量氮氧化物的产生,为了解决该问题,采用LNT-SCR耦合的NO_(x)净化技... 为了实现碳中和目标,降低内燃机碳排放,稀薄燃烧技术成为了当前重要的研究方向.该技术不仅能提高发动机燃油热效率,还能有效降低CO_(2)排放.但是稀薄燃烧往往会伴随着大量氮氧化物的产生,为了解决该问题,采用LNT-SCR耦合的NO_(x)净化技术,此时LNT的作用是将排气中部分NO_(x)转化为NH_(3),为下游的SCR提供还原剂.基于此,制备了LNT催化剂,研究催化剂对NO选择性生成NH_(3)的影响.采用溶胶-凝胶法制备了La_(1-x)Ce_(x)MnO_(3)系列钙钛矿氧化物,并通过分步浸渍法得到了La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)负载型催化剂.利用XRD、H_(2)-TPR、NO-TPD等表征手段研究了钙钛矿氧化物的晶相结构,以及负载型催化剂的还原特性、NO_(x)吸附-脱附性能等物化性质,并且通过H_(2)选择性催化还原NO实验探究了催化剂掺杂Ce对NO转化成NH_(3)的影响.结果表明,Ce掺杂催化剂具有良好的NH_(3)产物选择性,并且显著提高了NO转化率.温度是NO转化和NH_(3)产物选择性生成的决定性因素,而H_(2)和NO体积比是NO转化和NH_(3)产物选择性生成的关键性因素.其中,La_(0.95)Ce_(0.05)MnO_(3)-Ba/Al_(2)O_(3)在低温下催化活性表现最佳,在350℃、H_(2)和NO体积比为5.0时NH_(3)产物选择性为65%,NO转化率为100%.此外,所制备的La_(1-x)Ce_(x)MnO_(3)都形成了钙钛矿型结构,而且Ce掺杂催化剂的大部分Ce离子可以进入到LaMnO_(3)结构中.在催化剂适量掺杂Ce后,H_(2)消耗总面积增大、还原峰的峰值温度降低,表明掺杂Ce改善了催化剂的还原特性;同时NO吸附和脱附面积增大,表明Ce掺杂改变了催化剂的NO_(x)吸附-脱附性能. 展开更多
关键词 La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)催化剂 H_(2)选择性催化还原NO NH_(3)产物选择性 NO转化率 晶相结构 还原特性 NO_(x)吸附-脱附
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湿CO_(2)环境中316不锈钢腐蚀行为研究
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作者 刘方志 曹胜江 +4 位作者 李一未 张猛 李鹏 顾添帅 白佳佳 《非常规油气》 2024年第5期132-140,共9页
针对CO_(2)管输过程中碳钢因发生腐蚀而导致失效的问题,开展了316不锈钢的腐蚀行为研究。使用失重法研究含水率、CO_(2)分压以及Cl-浓度对316不锈钢腐蚀行为的影响,并绘制了腐蚀特征图谱;采用扫描电镜分析了腐蚀产物的微光形貌,X-射线... 针对CO_(2)管输过程中碳钢因发生腐蚀而导致失效的问题,开展了316不锈钢的腐蚀行为研究。使用失重法研究含水率、CO_(2)分压以及Cl-浓度对316不锈钢腐蚀行为的影响,并绘制了腐蚀特征图谱;采用扫描电镜分析了腐蚀产物的微光形貌,X-射线衍射仪分析了腐蚀产物成分。结果表明:316不锈钢在管输CO_(2)工况条件下表现出较好的耐腐蚀性,处于轻度腐蚀状态,腐蚀速率极低;316不锈钢腐蚀速率随含水率的增大而增大,随CO_(2)分压的增大而减小,随Cl-浓度的增加而增大;316不锈钢含有Cr可以在不锈钢表面形成致密的钝化膜,这使得Cr成为不锈钢防腐的关键;由于316不锈钢腐蚀速率远小于碳钢,在腐蚀“重灾区”,可以考虑将集输管道更换成316不锈钢。该研究成果为CCUS中CO_(2)管输钢材的选型提供重要的理论依据。 展开更多
关键词 管输CO_(2) 316不锈钢 腐蚀特征图谱 腐蚀形貌 腐蚀产物成分
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南川常压海相页岩气注CO_(2)吞吐提高采收率工程实践
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作者 姚红生 房大志 +5 位作者 卢义玉 王白雪 陆朝晖 谷红陶 闫卓林 苗诗谱 《天然气工业》 EI CAS CSCD 北大核心 2024年第4期83-92,共10页
当前研究实验和模拟论证了注CO_(2)吞吐提高页岩气采收率的理论可行性,然而其实际工程效果尚未得到现场试验的验证。为此,基于四川盆地南川常压海相页岩气藏地质赋存及生产特征,开展了页岩等温吸附和CO_(2)—CH_(4)竞争吸附机理研究,实... 当前研究实验和模拟论证了注CO_(2)吞吐提高页岩气采收率的理论可行性,然而其实际工程效果尚未得到现场试验的验证。为此,基于四川盆地南川常压海相页岩气藏地质赋存及生产特征,开展了页岩等温吸附和CO_(2)—CH_(4)竞争吸附机理研究,实施了国内首次常压海相页岩气衰减井CO_(2)吞吐现场试验,并提出了构建成套技术体系的攻关方向。研究结果表明:①气井生产到后期进入低压低产阶段,表现出地层能量不足的特征,是提高气井采出程度的重要阶段;②常压页岩的CH_(4)和CO_(2)吸附能力明显高于低压或高压页岩,采用CO_(2)提采更具可行性和必要性;③相同条件下的常压、高压和低压3组页岩样品均表现出对CO_(2)的吸附量大于对CH_(4)的吸附量,且对气体的吸附能力依次为南川(常压海相)页岩>长宁(高压海相)页岩>延长(低压陆相)页岩;④试验井注CO_(2)吞吐增产效果明显,页岩气单井预测最终可采储量(EUR)从0.75×10^(8) m^(3)上升到0.90×10^(8) m^(3),单井控制储量5.186×10^(8) m^(3),预计采收率提高了2.9%。结论认为:①实施的国内首次常压海相页岩气衰减井注CO_(2)吞吐试验取得突破性进展,为我国页岩气井提高采收率技术研发与应用提供了重要借鉴与参考;②亟需开展页岩气衰减井CO_(2)提采资源潜力与时机评估、提采效果定量评价与工艺优化等研究,并形成页岩气衰减井注CO_(2)吞吐提高采收率成套关键技术及标准体系。 展开更多
关键词 四川盆地 南川常压海相页岩气 衰减井 生产特征 注CO_(2)吞吐 提高采收率 驱替置换 碳封存
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Cu-Zn-based alloy/oxide interfaces for enhanced electroreduction of CO_(2) to C_(2+) products 被引量:8
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作者 Zi-Yang Zhang Hao Tian +3 位作者 Lei Bian Shi-Ze Liu Yuan Liu Zhong-Li Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期90-97,I0004,共9页
The electrochemical CO_(2)reduction reaction to produce multi-carbon(C_(2+)) hydrocarbons or oxygenate compounds is a promising route to obtain a renewable fuel of high energy density.However,producing C_(2+)at high c... The electrochemical CO_(2)reduction reaction to produce multi-carbon(C_(2+)) hydrocarbons or oxygenate compounds is a promising route to obtain a renewable fuel of high energy density.However,producing C_(2+)at high current densities is still a challenge.Herein,we develop a Cu-Zn alloy/Cu-Zn aluminate oxide composite electrocatalytic system for enhanced conversion of CO_(2)to C_(2+)products.The Cu-Zn-Al-Layered Double Hydroxide(LDH) is used as a precursor to decompose into uniform Cu-Zn oxide/Cu-Zn aluminate pre-catalyst.Under electrochemical reduction,Cu-Zn oxide generates Cu-Zn alloy while Cu-Zn aluminate oxide remains unchanged.The alloy and oxide are closely stacked and arranged alternately,and the aluminate oxide induces the strong electron interaction of Cu,Zn and Al,creating a large number of highly active reaction interfaces composed of 0 to+3 valence metal sites.With the help of the interface effect,the optimized Cu_(9)Zn_(1)/Cu_(0.8)Zn_(0.2)Al_(2)O_(4)catalyst achieves a Faradaic efficiency of 88.5% for C_(2+)products at a current density of 400 mA cm^(-2)at-1.15 V versus reversible hydrogen electrode.The in-situ Raman and attenuate total reflectance-infrared absorption spectroscopy(ATR-IRAS) spectra show that the aluminate oxide at the interface significantly enhances the adsorption and activation of CO_(2)and the dissociation of H2O and strengthens the adsorption of CO intermediates,and the alloy promotes the C-C coupling to produce C_(2+)products.This work provides an efficient strategy to construct highly active reaction interfaces for industrial-scale electrochemical CO_(2)RR. 展开更多
关键词 Electrochemical CO_(2)reduction reaction C_(2+)products Cu-Zn alloy Cu-Zn aluminate oxide Interface
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NiPd/TiO_(2)催化剂的制备及催化甲酸分解制氢 被引量:4
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作者 吴慧 郑君宁 +3 位作者 左佑华 许立信 叶明富 万超 《精细化工》 EI CAS CSCD 北大核心 2024年第6期1302-1309,共8页
高效、清洁且无毒无害的催化剂是实现以甲酸(HCOOH)为化学储氢材料分解制氢的重点。首先,通过水热法453 K下制备了TiO_(2)载体;然后,通过浸渍法将活性组分Ni、Pd负载到TiO_(2)载体上合成了NiPd/TiO_(2)催化剂。采用SEM、TEM、N2吸附-脱... 高效、清洁且无毒无害的催化剂是实现以甲酸(HCOOH)为化学储氢材料分解制氢的重点。首先,通过水热法453 K下制备了TiO_(2)载体;然后,通过浸渍法将活性组分Ni、Pd负载到TiO_(2)载体上合成了NiPd/TiO_(2)催化剂。采用SEM、TEM、N2吸附-脱附、XRD、XPS、UV-Vis DRS对催化剂样品进行了表征。探究了由不同n(Ni)∶n(Pd)制备的催化剂对催化甲酸分解制氢性能的影响。结果表明,NiPd金属粒子对TiO_(2)的改性不仅扩大了TiO_(2)的光吸收范围,还有助于电荷分离,加速光催化反应的进行。在光照下,当NiPd/TiO_(2)催化剂中n(Ni)∶n(Pd)=2∶8时,催化剂的反应转化频率(TOF)最大,为3528 h^(–1)(323 K下),甲酸分解的活化能(E_(a))为53.9 kJ/mol。 展开更多
关键词 NiPd催化剂 甲酸 分解制氢 TiO_(2) 光照
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Electric-field promoted C–C coupling over Cu nanoneedles for CO_(2) electroreduction to C_(2) products 被引量:5
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作者 HuangJingWei Li Huimin Zhou +4 位作者 Yajiao Zhou Junhua Hu Masahiro Miyauchi Junwei Fu Min Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第2期519-525,共7页
Cu-based catalysts are the most promising candidates for electrochemical CO_(2)reduction(CO_(2)RR)to multi-carbon(C_(2))products.Optimizing the C-C coupling process,the rate-determining step for C_(2)product generatio... Cu-based catalysts are the most promising candidates for electrochemical CO_(2)reduction(CO_(2)RR)to multi-carbon(C_(2))products.Optimizing the C-C coupling process,the rate-determining step for C_(2)product generation,is an important strategy to improve the production and selectivity of the C_(2)products.In this study,we determined that the local electric field can promote the C-C coupling reaction and enhance CO_(2)electroreduction to C_(2)products.First,finite-element simulations indicated that the high curvature of the Cu nanoneedles results in a large local electric field on their tips.Density functional theory(DFT)calculations proved that a large electric field can promote C-C coupling.Motivated by this prediction,we prepared a series of Cu catalysts with different curvatures.The Cu nanoneedles(NNs)exhibited the largest number of curvatures,followed by the Cu nanorods(NRs),and Cu nanoparticles(NPs).The Cu NNs contained the highest concentration of adsorbed K+,which resulted in the highest local electric field on the needles.CO adsorption sensor tests indicated that the Cu NNs exhibited the strongest CO adsorption ability,and in-situ Fourier-transform infrared spectroscopy(FTIR)showed the strongest*COCO and*CO signals for the Cu NNs.These experimental results demonstrate that high-curvature nanoneedles can induce a large local electric field,thus promoting C-C coupling.As a result,the Cu NNs show a maximum FEC_(2)of 44%for CO_(2)RR at a low potential(-0.6 V vs.RHE),which is approximately 2.2 times that of the Cu NPs.This work provides an effective strategy for enhancing the production of multi-carbon products during CO_(2)RR. 展开更多
关键词 Electric-field effect C–C coupling Cu nanoneedle C_(2)products CO_(2)electroreduction
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Tuning the intermediate reaction barriers by a CuPd catalyst to improve the selectivity of CO_(2) electroreduction to C_(2) products 被引量:5
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作者 Li Zhu Yiyang Lin +8 位作者 ang Liu Emiliano Cortés Hongmei Li Junhua Hu Akira Yamaguchi Xiaoliang Liu Masahiro Miyauchi Junwei Fu Min Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第9期1500-1508,共9页
Electrochemical CO2 reduction is a promising strategy for the utilization of CO2 and intermittent excess electricity.Cu is the only single metal catalyst that can electrochemically convert CO2 into multicarbon product... Electrochemical CO2 reduction is a promising strategy for the utilization of CO2 and intermittent excess electricity.Cu is the only single metal catalyst that can electrochemically convert CO2 into multicarbon products.However,Cu exhibits an unfavorable activity and selectivity for the generation of C2 products because of the insufficient amount of CO*provided for the C‐C coupling.Based on the strong CO2 adsorption and ultrafast reaction kinetics of CO*formation on Pd,an intimate CuPd(100)interface was designed to lower the intermediate reaction barriers and improve the efficiency of C2 product formation.Density functional theory(DFT)calculations showed that the CuPd(100)interface enhanced the CO2 adsorption and decreased the CO2*hydrogenation energy barrier,which was beneficial for the C‐C coupling.The potential‐determining step(PDS)barrier of CO2 to C2 products on the CuPd(100)interface was 0.61 eV,which was lower than that on Cu(100)(0.72 eV).Encouraged by the DFT calculation results,the CuPd(100)interface catalyst was prepared by a facile chemical solution method and characterized by transmission electron microscopy.CO2 temperature‐programmed desorption and gas sensor experiments further confirmed the enhancement of the CO2 adsorption and CO2*hydrogenation ability of the CuPd(100)interface catalyst.Specifically,the obtained CuPd(100)interface catalyst exhibited a C2 Faradaic efficiency of 50.3%±1.2%at‒1.4 VRHE in 0.1 M KHCO3,which was 2.1 times higher than that of the Cu catalyst(23.6%±1.5%).This study provides the basis for the rational design of Cu‐based electrocatalysts for the generation of multicarbon products by fine‐tuning the intermediate reaction barriers. 展开更多
关键词 Carbon dioxide reduction C2 products ELECTROCATALYST Copper‐palladium interface Intermediate reaction barriers
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Natural products for cancer prevention associated with Nrf2–ARE pathway 被引量:5
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作者 Xianjuan Kou Michael Kirberger +1 位作者 Yi Yang Ning Chen 《Food Science and Human Wellness》 SCIE 2013年第1期22-28,共7页
Cancer chemoprevention involves the application of natural or synthetic compounds to reduce the risk of cancer development.One of the most effective strategies for preventing human cancers might involve inducing phase... Cancer chemoprevention involves the application of natural or synthetic compounds to reduce the risk of cancer development.One of the most effective strategies for preventing human cancers might involve inducing phase II detoxifying enzymes and antioxidant enzymes via natural dietary compounds.The regulatory regions of these inducible genes encode the antioxidant response element(ARE).Nuclear factor-erythroid 2-related factor 2(Nrf2),as a transcription factor,plays a key role in the expression of ARE-mediated genes.Similarly,Nrf2 performs an essential function in the up-regulation of these genes in response to oxidative stress and treatment with dietary phytochemicals.In this article,we discuss the current state of knowledge regarding the Nrf2/ARE pathway as a potential molecular target for cancer chemoprevention and its molecular regulation mechanisms,and highlight Nrf2/ARE inducers derived from natural products,which may be used as chemopreventive agents for cancer patients.©2013 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved. 展开更多
关键词 Natural products Cancer prevention Nrf2-ARE pathway TUMORIGENESIS Dietary phytochemicals
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