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Molten salt construction of core-shell structured S-scheme CuInS_(2)@CoS_(2) heterojunction to boost charge transfer for efficient photocatalytic CO_(2) reduction
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作者 Fulin Wang Xiangwei Li +3 位作者 Kangqiang Lu Man Zhou Changlin Yu Kai Yang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期190-201,共12页
Weak redox ability and severe charge recombination pose significant obstacles to the advancement of CO_(2) photoreduction.To tackle this challenge and enhance the CO_(2) photoconversion efficiency,fabricating well-mat... Weak redox ability and severe charge recombination pose significant obstacles to the advancement of CO_(2) photoreduction.To tackle this challenge and enhance the CO_(2) photoconversion efficiency,fabricating well-matched S-scheme heterostructure and establishing a robust built-in electric field emerge as pivotal strategies.In pursuit of this goal,a core-shell structured CuInS_(2)@CoS_(2)S-scheme heterojunction was meticulously engineered through a two-step molten salt method.This approach over the CuInS_(2)-based composites produced an internal electric field owing to the disparity be-tween the Fermi levels of CoS_(2) and CuInS_(2) at their interface.Consequently,the electric field facili-tated the directed migration of charges and the proficient separation of photoinduced carriers.The resulting CuInS_(2)@CoS_(2) heterostructure exhibited remarkable CO_(2) photoreduction performance,which was 21.7 and 26.5 times that of pure CuInS_(2) and CoS_(2),respectively.The S-scheme heterojunc-tion photogenerated charge transfer mechanism was validated through a series of rigorous anal-yses,including in situ irradiation X-ray photoelectron spectroscopy,work function calculations,and differential charge density examinations.Furthermore,in situ infrared spectroscopy and density functional theory calculations corroborated the fact that the CuInS_(2)@CoS_(2) heterojunction substan-tially lowered the formation energy of *COOH and *CO.This study demonstrates the application potential of S-scheme heterojunctions fabricated via the molten salt method in the realm of ad-dressing carbon-related environmental issues. 展开更多
关键词 S-scheme heterojunction Molten salt CuInS_(2)cos_(2) CO_(2) photoreduction
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LiSi/CoS_(2)体系在小电流长工作时间热电池的应用研究
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作者 占志强 欧阳琼 +3 位作者 陈祥华 梁顺飞 韩晓丽 唐立成 《电源技术》 CAS 北大核心 2024年第7期1346-1350,共5页
结合热电池的特点,开展了LiSi/CoS_(2)热电池体系小电流密度工作时的电解质匹配性研究、电解质配比研究、热量匹配研究以及在长工作时间热电池的电性能对比研究。实验结果表明:LiSi/CoS_(2)体系小电流密度工作,与LiF-LiBr-KBr电解质匹... 结合热电池的特点,开展了LiSi/CoS_(2)热电池体系小电流密度工作时的电解质匹配性研究、电解质配比研究、热量匹配研究以及在长工作时间热电池的电性能对比研究。实验结果表明:LiSi/CoS_(2)体系小电流密度工作,与LiF-LiBr-KBr电解质匹配性较好,最佳的电解质配比为m_(LiF-LiBr-KBr)/m_(MgO)=60/40,最佳的热比值设计为0.70;LiSi/CoS_(2)体系热电池小电流密度工作的放电容量比LiSi/FeS_(2)体系增加了31%,比LiB/CoS_(2)体系具有更高的经济效益,更适合于小电流长工作时间热电池的工程化应用。 展开更多
关键词 LiSi/cos_(2) 热电池 长工作时间
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AGK2 pre-treatment protects against thioacetamide-induced acute liver failure via regulating the MFN2-PERK axis and ferroptosis signaling pathway 被引量:2
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作者 Qing-Qi Zhang Qian Chen +4 位作者 Pan Cao Chun-Xia Shi Lu-Yi Zhang Lu-Wen Wang Zuo-Jiong Gong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第1期43-51,共9页
Background:Acute liver failure(ALF)is an unpredictable and life-threatening critical illness.The pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which ... Background:Acute liver failure(ALF)is an unpredictable and life-threatening critical illness.The pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which may lead to multiple organ failure.Methods:Animals were divided into 3 groups,normal,thioacetamide(TAA,ALF model)and TAA+AGK2.Cultured L02 cells were divided into 5 groups,normal,TAA,TAA+mitofusin 2(MFN2)-siRNA,TAA+AGK2,and TAA+AGK2+MFN2-siRNA groups.The liver histology was evaluated with hematoxylin and eosin staining,inositol-requiring enzyme 1(IRE1),activating transcription factor 6β(ATF6β),protein kinase R(PKR)-like endoplasmic reticulum kinase(PERK)and phosphorylated-PERK(p-PERK).C/EBP homologous protein(CHOP),reactive oxygen species(ROS),MFN2 and glutathione peroxidase 4(GPX4)were measured with Western blotting,and cell viability and liver chemistry were also measured.Mitochondriaassociated endoplasmic reticulum membranes(MAMs)were measured by immunofluorescence.Results:The liver tissue in the ALF group had massive inflammatory cell infiltration and hepatocytes necrosis,which were reduced by AGK2 pre-treatment.In comparison to the normal group,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+in the TAA-induced ALF model group were significantly increased,which were decreased by AGK2 pre-treatment.The levels of MFN2 and GPX4 were decreased in TAA-induced mice compared with the normal group,which were enhanced by AGK2 pretreatment.Compared with the TAA-induced L02 cell,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+were further increased and levels of MFN2 and GPX4 were decreased in the MFN2-siRNA group.AGK2 pre-treatment decreased the apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+and enhanced the protein expression of MFN2 and GPX4 in MFN2-siRNA treated L02 cell.Immunofluorescence observation showed that level of MAMs was promoted in the AGK2 pre-treatment group when compared with the TAA-induced group in both mice and L02 cells.Conclusions:The data suggested that AGK2 pre-treatment had hepatoprotective role in TAA-induced ALF via upregulating the expression of MFN2 and then inhibiting PERK and ferroptosis pathway in ALF. 展开更多
关键词 SIRT2 inhibitor AGK2 Acute liver failure MFN2 Ferroptosis
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基于GEE的Landsat-8与Sentinel-2影像在棉花种植提取中差异性分析及提取方法对比研究 被引量:1
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作者 洪国军 周保平 +5 位作者 李明哲 李森威 刘成成 张灵 付仙兵 李旭 《江苏农业科学》 北大核心 2024年第4期223-230,共8页
棉花作为南疆地区重要的经济作物之一,在经济工作中起着至关重要的作用。及时、准确地获取棉花种植面积,对农业政策和经济发展具有重要意义。为了实现这一目标,需要综合分析不同方法和遥感数据对最终棉花种植面积制图精度的影响。本研... 棉花作为南疆地区重要的经济作物之一,在经济工作中起着至关重要的作用。及时、准确地获取棉花种植面积,对农业政策和经济发展具有重要意义。为了实现这一目标,需要综合分析不同方法和遥感数据对最终棉花种植面积制图精度的影响。本研究以新疆阿克苏地区棉花种植区为例,借助Google Earth Engine云平台,采用随机森林法(RF)、支持向量机法(SVM)、最小距离分类法(MDC)等3种机器学习方法,利用2类中分辨率影像提取棉花种植信息,充分评估使用的档案数据和官方统计数字。结果表明,采用Sentinel-2方法和RF获得了最优棉花图,随机森林法分类器的总体精度、Kappa系数和用户精度分别高达97.4%、96.7%和91.1%,分别比Landsat-8图像和RF模型的结果高出7.3百分点、0.081、2.8百分点。与官方统计数据相比,采用RF、SVM、MDC对Sentinel-2和Landsat-8图像的棉花种植面积估算图的精度分别为98.4%、95.8%、79.6%和90.3%、83.7%、72.5%。很明显,Sentinel-2和RF模型的组合与官方数据的一致性最高。对比分析结果表明,Landsat-8和Sentinel-2数据可用于大范围复杂种植结构的棉花高精度测绘。本研究结果有望为棉花大面积鉴别提供一定的理论指导和实践指导。 展开更多
关键词 棉花分类 Sentinel-2 Landsat-8 随机森林 支持向量机 最小距离分类 Google Earth Engine
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基于Sentinel-1结合Sentinel-2和Landsat8影像的水体提取方法比较——以鲁班水库为例
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作者 苏子昕 青玲萱 +4 位作者 王鑫 薛飞阳 王旭 秦翔宇 杨存建 《四川林业科技》 2024年第1期111-114,共4页
基于sentinel-1数据结合sentinel-2数据和Landsat8数据,提取2017年—2021年鲁班水库五年间的水体年间变化,对所提取的水体面积进行分析,比较两种影像对鲁班水库水体提取的差异,经过水体指数的计算以及分析得到鲁班水库的水体面积。senti... 基于sentinel-1数据结合sentinel-2数据和Landsat8数据,提取2017年—2021年鲁班水库五年间的水体年间变化,对所提取的水体面积进行分析,比较两种影像对鲁班水库水体提取的差异,经过水体指数的计算以及分析得到鲁班水库的水体面积。sentinel-2影像数据对水体提取的效果较好于Landsat8数据,sentinel-2影像总体分类精度达0.993,kappa系数为0.991,而Landsat8的总体精度为0.989,kappa系数为0.986。通过对鲁班水库这种大中型水体的水体提取选择使用sentinel-2数据较好。 展开更多
关键词 水体提取 水体指数 Sentinel-2 Landsat8 Sentinel-1
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宫颈癌患者lncRNA HAND2-AS1表达及其对宫颈癌Caski细胞增殖、侵袭和迁移能力的影响 被引量:1
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作者 张晓科 褚艳荣 +1 位作者 王荣 崔发财 《检验医学》 CAS 2024年第5期429-437,共9页
目的探讨宫颈癌患者血清长链非编码RNA(lncRNA)心脏和神经嵴衍生物表达转录本2反义序列1(HAND2-AS1)表达的临床意义,分析lncRNA HAND2-AS1对宫颈癌Caski细胞增殖、侵袭和迁移的影响机制。方法采用基因表达交互分析(GEPIA)数据库分析lncR... 目的探讨宫颈癌患者血清长链非编码RNA(lncRNA)心脏和神经嵴衍生物表达转录本2反义序列1(HAND2-AS1)表达的临床意义,分析lncRNA HAND2-AS1对宫颈癌Caski细胞增殖、侵袭和迁移的影响机制。方法采用基因表达交互分析(GEPIA)数据库分析lncRNA HAND2-AS1在宫颈癌组织和正常宫颈组织中的表达情况。选取2019年1月—2021年12月焦作市妇幼保健院宫颈癌患者48例(宫颈癌组)、宫颈上皮内瘤变(CIN)患者48例(CIN组)和健康体检者48名(正常对照组)。收集其中14例宫颈癌患者术后癌组织和癌旁组织(距癌组织边缘>2 cm)样本,同时收集所有研究对象血清样本和临床资料,检测lncRNA HAND2-AS1相对表达量。将宫颈癌细胞系Caski按转染质粒的不同分为过表达组(转染pcDNA3.1-HAND2-AS1)和阴性对照组(转染pcDNA3.1-NC)、干扰组(转染si-HAND2-AS1)和干扰对照组(转染si-NC)。采用CCK-8实验、Transwell实验和划痕实验检测细胞的增殖、侵袭和迁移能力,采用免疫印迹法检测细胞内磷脂酰肌醇3-激酶(PI3K)、磷酸化磷脂酰肌醇3-激酶(p-PI3K)、蛋白激酶B(Akt)和磷酸化蛋白激酶B(p-Akt)的表达情况。结果GEPIA数据库分析结果显示,宫颈癌组织lncRNA HAND2-AS1表达显著低于正常宫颈上皮组织(P<0.05)。14例宫颈癌患者癌组织lncRNA HAND2-AS1相对表达量显著低于癌旁组织(P=0.001)。宫颈癌组血清lncRNA HAND2-AS1相对表达量显著低于CIN组和正常对照组(P<0.001),CIN组与正常对照组之间差异无统计学意义(P>0.05)。不同肿瘤大小、国际妇产科学联合会(FIGO)分期和有无淋巴转移的宫颈癌患者之间血清lncRNA HAND2-AS1相对表达量差异均有统计学意义(P<0.05)。过表达组lncRNA HAND2-AS1相对表达量显著高于阴性对照组(P<0.01),细胞增殖活性、侵袭细胞数、划痕愈合率和p-PI3K、p-Akt蛋白相对表达量均低于阴性对照组(P<0.05)。干扰组lncRNA HAND2-AS1相对表达量显著低于干扰对照组(P<0.001),细胞增殖活性、侵袭细胞数、划痕愈合率和p-PI3K、p-Akt蛋白相对表达量均显著高于干扰对照组(P<0.05)。过表达组与阴性对照组之间、干扰组与干扰对照组之间PI3K和Akt蛋白相对表达量差异均无统计学意义(P>0.05)。结论宫颈癌患者血清lncRNA HAND2-AS1呈低表达,且与病情严重程度有关。lncRNA HAND2-AS1可能通过调控PI3K/Akt信号通路影响宫颈癌细胞的增殖、侵袭和迁移。 展开更多
关键词 心脏和神经嵴衍生物表达转录本2反义序列1 长链非编码RNA 宫颈癌 侵袭 迁移
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C-H bond activation of propane on Ga_(2)O_(2)^(2+) in Ga/H-ZSM-5 and its mechanistic implications
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作者 Zhaoqi Zhao Yunzhu Zhong +1 位作者 Xiaoxia Chang Bingjun Xu 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期32-43,共12页
Propane dehydrogenation(PDH)on Ga/H-ZSM-5 catalysts is a promising reaction for propylene production,while the detail mechanism remains debatable.Ga_(2)O_(2)^(2+) stabilized by framework Al pairs have been identified ... Propane dehydrogenation(PDH)on Ga/H-ZSM-5 catalysts is a promising reaction for propylene production,while the detail mechanism remains debatable.Ga_(2)O_(2)^(2+) stabilized by framework Al pairs have been identified as the most active species in Ga/H-ZSM-5 for PDH in our recent work.Here we demonstrate a strong correlation between the PDH activity and a fraction of Ga_(2)O_(2)^(2+) species corresponding to the infrared GaH band of higher wavenumber(GaHHW)in reduced Ga/H-ZSM-5,instead of the overall Ga_(2)O_(2)^(2+) species,by employing five H-ZSM-5 supports sourced differently with comparable Si/Al ratio.This disparity in Ga_(2)O_(2)^(2+) species stems from their differing capacity in completing the catalytic cycle.Spectroscopic results suggest that PDH proceeds via a two-step mechanism:(1)C-H bond activation of propane on H-Ga_(2)O_(2)^(2+) species(rate determining step);(2)β-hydride elimination of adsorbed propyl group,which only occurs on active Ga_(2)O_(2)^(2+) species corresponding to GaHHW. 展开更多
关键词 Propane dehydrogenation Ga_(2)O_(2)^(2+) Activation of C-H bond Ga species
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Mechanism study on the influence of surface properties on the synthesis of dimethyl carbonate from CO_(2)and methanol over ceria catalysts
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作者 Lei Dong Shengjie Zhu +4 位作者 Yangyang Yuan Xiaomin Zhang Xiaowei Zhao Yanping Chen Lei Xu 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期138-152,共15页
The direct synthesis of dimethyl carbonate(DMC)from CO_(2)and methanol has attracted much attention as an environmentally benign and alternative route for conventional routes.Herein,a series of cerium oxide catalysts ... The direct synthesis of dimethyl carbonate(DMC)from CO_(2)and methanol has attracted much attention as an environmentally benign and alternative route for conventional routes.Herein,a series of cerium oxide catalysts with various textural features and surface properties were prepared by the one-pot synthesis method for the direct DMC synthesis from CO_(2)and methanol,and the structure-performance relationship was investigated in detail.Characterization results revealed that both of surface acid-base properties and the oxygen vacancies contents decreased with the rising crystallinity at increasingly higher calcination temperature accompanied by an unexpectedly volcano-shaped trend of DMC yield observed on the catalysts.In situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)studies indicated that the adsorption rate of methanol is slower than that of CO_(2)and the methanol activation state largely influences the formation of key intermediate.Although the enhanced surface acidity-basicity and oxygen vacancies brought by low-temperature calcination could facilitate the activation of CO_(2),the presence of excess strongly basic sites on low-crystallinity sample was detrimental to DMC synthesis due to the preferred formation of unreactive mono/polydentate carbonates as well as the further impediment of methanol activation.Moreover,with the use of 2-cyanopyridine as a dehydration reagent,the DMC synthesis was found to be both influenced by the promotion from the rapid in situ removal of water and the inhibition from the competitive adsorption of hydration products on the same active sites. 展开更多
关键词 CeO_(2) Dimethyl carbonate Surface property Methanol activation 2-Cyanopyridine
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Histopathological impact of SARS-CoV-2 on the liver:Cellular damage and long-term complications 被引量:1
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作者 Alfonso Rodriguez-Espada Moises Salgado-de la Mora +4 位作者 Briana Mariette Rodriguez-Paniagua Nathaly Limonde la Rosa Monica Itzel Martinez-Gutierrez Santiago Pastrana-Brandes Nalu Navarro-Alvarez 《World Journal of Gastroenterology》 SCIE CAS 2024年第22期2866-2880,共15页
Coronavirus disease 2019(COVID-19),caused by the highly pathogenic severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),primarily impacts the respiratory tract and can lead to severe outcomes such as acute resp... Coronavirus disease 2019(COVID-19),caused by the highly pathogenic severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),primarily impacts the respiratory tract and can lead to severe outcomes such as acute respiratory distress syndrome,multiple organ failure,and death.Despite extensive studies on the pathogenicity of SARS-CoV-2,its impact on the hepatobiliary system remains unclear.While liver injury is commonly indicated by reduced albumin and elevated bilirubin and transaminase levels,the exact source of this damage is not fully understood.Proposed mechanisms for injury include direct cytotoxicity,collateral damage from inflammation,drug-induced liver injury,and ischemia/hypoxia.However,evidence often relies on blood tests with liver enzyme abnormalities.In this comprehensive review,we focused solely on the different histopathological manifestations of liver injury in COVID-19 patients,drawing from liver biopsies,complete autopsies,and in vitro liver analyses.We present evidence of the direct impact of SARS-CoV-2 on the liver,substantiated by in vitro observations of viral entry mechanisms and the actual presence of viral particles in liver samples resulting in a variety of cellular changes,including mitochondrial swelling,endoplasmic reticulum dilatation,and hepatocyte apoptosis.Additional ly,we describe the diverse liver pathology observed during COVID-19 infection,encompassing necrosis,steatosis,cholestasis,and lobular inflammation.We also discuss the emergence of long-term complications,notably COVID-19-related secondary sclerosing cholangitis.Recognizing the histopathological liver changes occurring during COVID-19 infection is pivotal for improving patient recovery and guiding decision-making. 展开更多
关键词 LIVER SARS-CoV-2 COVID-19 Angiotensin-converting enzyme 2 HISTOPATHOLOGY Liver biopsies Liver autopsy In vitro
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金属有机骨架衍生CoS_(2)/NC作为高性能钠离子电池负极的研究
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作者 傅世郑 安鹏燕 +5 位作者 董默涵 王舒冉 杨浩 王子丹 边煜华 刘朝孟 《电力科技与环保》 2024年第3期258-265,共8页
随着能源的持续消耗和需求量日益增加,电化学储能器件飞速发展。钠离子电池作为锂电的替代储能体系成为研究重点,电极材料作为关键组成部件对电池的性能起着重要作用。过渡金属硫化物因其高理论比容量可作为钠电负极而备受关注,且储量丰... 随着能源的持续消耗和需求量日益增加,电化学储能器件飞速发展。钠离子电池作为锂电的替代储能体系成为研究重点,电极材料作为关键组成部件对电池的性能起着重要作用。过渡金属硫化物因其高理论比容量可作为钠电负极而备受关注,且储量丰富,价格低廉,但是存在离子存储过程的氧化还原反应导致体积变化引起结构退化等问题。本文以高容量的硫化钴作为研究对象,设计在一个相对刚性的基体中束缚住硫化钴颗粒,限制离子插嵌过程中硫化钴的体积膨胀。主要通过溶剂热法制备金属有机骨架ZIF-67,以ZIF-67为前驱体,经高温碳化及硫化反应,合成氮掺杂碳包覆CoS_(2)纳米颗粒的复合材料(CoS_(2)/NC)。采用X射线衍射等研究方法对其进行测试,揭示了CoS_(2)/NC的储钠机理。结果表明:CoS_(2)/NC负极材料具有极高的比容量和良好的循环稳定性,在60 mA/g电流密度下的比容量达到了599.6 mA·h/g,在1200 mA/g电流密度下循环500圈后仍可保持455.4 mA·h/g的高容量。较小的电化学阻抗和较高的电容贡献率保证了电极材料优良的倍率性能和大电流密度下的循环性能。CoS_(2)/NC电极表现出优异的储钠性能,有望成为下一代高性能负极材料。改性策略操作简单、效果显著,可以广泛应用于其他电化学储能器件中。 展开更多
关键词 cos2/NC复合材料 钠离子电池 负极材料 电化学性能 金属有机框架
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Cu-Based Materials for Enhanced C_(2+) Product Selectivity in Photo-/Electro-Catalytic CO_(2) Reduction: Challenges and Prospects 被引量:1
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作者 Baker Rhimi Min Zhou +2 位作者 Zaoxue Yan Xiaoyan Cai Zhifeng Jiang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期25-66,共42页
Carbon dioxide conversion into valuable products using photocatalysis and electrocatalysis is an effective approach to mitigate global environmental issues and the energy shortages. Among the materials utilized for ca... Carbon dioxide conversion into valuable products using photocatalysis and electrocatalysis is an effective approach to mitigate global environmental issues and the energy shortages. Among the materials utilized for catalytic reduction of CO_(2), Cu-based materials are highly advantageous owing to their widespread availability, cost-effectiveness, and environmental sustainability. Furthermore, Cu-based materials demonstrate interesting abilities in the adsorption and activation of carbon dioxide, allowing the formation of C_(2+) compounds through C–C coupling process. Herein, the basic principles of photocatalytic CO_(2) reduction reactions(PCO_(2)RR) and electrocatalytic CO_(2) reduction reaction(ECO_(2)RR) and the pathways for the generation C_(2+) products are introduced. This review categorizes Cu-based materials into different groups including Cu metal, Cu oxides, Cu alloys, and Cu SACs, Cu heterojunctions based on their catalytic applications. The relationship between the Cu surfaces and their efficiency in both PCO_(2)RR and ECO_(2)RR is emphasized. Through a review of recent studies on PCO_(2)RR and ECO_(2)RR using Cu-based catalysts, the focus is on understanding the underlying reasons for the enhanced selectivity toward C_(2+) products. Finally, the opportunities and challenges associated with Cu-based materials in the CO_(2) catalytic reduction applications are presented, along with research directions that can guide for the design of highly active and selective Cu-based materials for CO_(2) reduction processes in the future. 展开更多
关键词 Photocatalytic CO_(2)reduction Cu-based materials Electrocatalytic CO_(2)reduction
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Involvement of the ABA-and H_(2)O_(2)-Mediated Ascorbate-Glutathione Cycle in the Drought Stress Responses of Wheat Roots 被引量:1
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作者 Mengyuan Li Zhongye Gao +2 位作者 Lina Jiang Leishan Chen Jianhui Ma 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期329-342,共14页
Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and th... Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and the AsA–GSH cycle under drought stress in wheat has not been studied.In this study,a hydroponic experiment was conducted in wheat seedlings subjected to 15%polyethylene glycol(PEG)6000–induced dehydration.Drought stress caused the rapid accumulation of endogenous ABA and H_(2)O_(2) and significantly decreased the number of root tips compared with the control.The application of ABA significantly increased the number of root tips,whereas the application of H_(2)O_(2) markedly reduced the number of root tips,compared with that under 15%PEG-6000.In addition,drought stress markedly increased the DHA,GSH and GSSG levels,but decreased the AsA levels,AsA/DHA and GSH/GSSG ratios compared with those in the control.The activities of the four enzymes in the AsA–GSH cycle were also markedly increased under drought stress,including glutathione reductase(GR),ascorbate peroxidase(APX),monodehydroascorbate reductase(MDHAR)and dehydroascorbate reductase(DHAR),compared with those in the control.However,the application of an ABA inhibitor significantly inhibited GR,DHAR and APX activities,whereas the application of an H_(2)O_(2) inhibitor significantly inhibited DHAR and MDHAR activities.Furthermore,the application of ABA inhibitor significantly promoted the increases of H_(2)O_(2) and the application of H_(2)O_(2) inhibitor significantly blocked the increases of ABA,compared with those under 15% PEG-6000.Taken together,the results indicated that ABA and H_(2)O_(2) probably interact under drought stress in wheat;and both of them can mediate drought stress by modulating the enzymes in AsA–GSH cycle,where ABA acts as the main regulator of GR,DHAR,and APX activities,and H_(2)O_(2) acts as the main regulator of DHAR and MDHAR activities. 展开更多
关键词 ABA H_(2)O_(2) AsA-GSH cycle drought stress wheat roots
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Evaluation of the intracellular lipid-lowering effect of polyphenols extract from highland barley in HepG2 cells 被引量:3
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作者 Yijun Yao Zhifang Li +2 位作者 Bowen Qin Xingrong Ju Lifeng Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期454-461,共8页
Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinat... Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4. 展开更多
关键词 Highland barley Polyphenols extract Lipid-lowering effect HepG2 cells
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High glucose reduces Nrf2-dependent cRAGE release and enhances inflammasome-dependent IL-1βproduction in monocytes:the modulatory effects of EGCG 被引量:1
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作者 Chi-Hao Wu Yin-Hsuan Chang +2 位作者 Chin-Lin Hsu Sheng-Yi Chen Gow-Chin Yen 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1531-1542,共12页
Soluble receptor for advanced glycation end products(sRAGE)acts as a decoy sequestering of RAGE ligands,thus preventing the activation of the ligand-RAGE axis linking human diseases.However,the molecular mechanisms un... Soluble receptor for advanced glycation end products(sRAGE)acts as a decoy sequestering of RAGE ligands,thus preventing the activation of the ligand-RAGE axis linking human diseases.However,the molecular mechanisms underlying sRAGE remain unclear.In this study,THP-1 monocytes were cultured in normal glucose(NG,5.5 mmol/L)and high glucose(HG,15 mmol/L)to investigate the effects of diabetesrelevant glucose concentrations on sRAGE and interleukin-1β(IL-1β)secretion.The modulatory effects of epigallocatechin gallate(EGCG)in response to HG challenge were also evaluated.HG enhanced intracellular reactive oxygen species(ROS)generation and RAGE expression.The secretion of sRAGE,including esRAGE and cRAGE,was reduced under HG conditions,together with the downregulation of a disintegrin and metallopeptidase 10(ADAM10)and nuclear factor erythroid 2-related factor 2(Nrf2)nuclear translocation.Mechanistically,the HG effects were counteracted by siRAGE and exacerbated by siNrf2.Chromatin immunoprecipitation results showed that Nrf2 binding to the ADAM10 promoter and HG interfered with this binding.Our data reinforce the notion that RAGE and Nrf2 might be sRAGE-regulating factors.Under HG conditions,the treatment of EGCG reduced ROS generation and RAGE activation.EGCG-stimulated cRAGE release was likely caused by the upregulation of the Nrf2-ADAM10 pathway.EGCG inhibited HG-mediated NLRP3 inflammasome activation at least partly by stimulating sRAGE,thereby reducing IL-1βrelease. 展开更多
关键词 Epigallocatechin gallate(EGCG) INFLAMMASOME Nuclear factor erythroid 2-related factor 2(Nrf2) Receptor for advanced glycation end products(RAGE) Soluble RAGE(sRAGE)
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Synthesis and Luminescence Improvement of CaAlSiN_(3) Phosphors Doped with Eu^(2+) and Mn^(2+) for White LEDs
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作者 WEI Dong SU Wenxia 《发光学报》 EI CAS CSCD 北大核心 2024年第10期1656-1666,共11页
Eu^(2+) and Mn^(2+) co-activated CaAlSiN_(3) red phosphors were produced using the solid-state reaction tech⁃nique in a N2 environment.Excitation spectra,emission spectra,and diffuse reflection spectra were used to st... Eu^(2+) and Mn^(2+) co-activated CaAlSiN_(3) red phosphors were produced using the solid-state reaction tech⁃nique in a N2 environment.Excitation spectra,emission spectra,and diffuse reflection spectra were used to study the luminescence characteristics,energy gap,and thermal stability in detail.CaAlSiN_(3)∶Eu^(2+) exhibits an extended emission band when stimulated with 450 nm blue light,which is caused by the 4f65d to 4f7 transition of Eu^(2+).Similar⁃ly,CaAlSiN_(3)∶Mn^(2+) displays a wide emission band centered at 628 nm,which results from Mn^(2+)’s transition from 4T1(4G) to 6A1(6S).When the ions of Mn^(2+)were combined into CaAlSiN_(3)∶Eu^(2+),the photoluminescence intensity of Eu^(2+ )was greatly boosted because there was energy transfer and co-emission between Mn^(2+) and Eu^(2+).Beyond that,CaAlSiN_(3)∶Eu^(2+),Mn^(2+) emerges with splendid thermostability and high quantum efficiency,the quenching temperature surpasses 300℃,and the internal quantum efficiency is determined to be around 84.9%.The white LED was pack⁃aged with a combination of CaAlSiN_(3)∶Eu^(2+),Mn^(2+),LuAG∶Ce3+ and a blue chip.At a warm white-light corresponding color temperature(3009 K) with CIE coordinates(0.4223,0.3748),the color rendering index Ra has reached 93.2.CaAlSiN_(3)∶Eu^(2+),Mn^(2+) would have great application potential as a red-emitting phosphor for white LEDs. 展开更多
关键词 energy transfer silicon nitrides CaAlSiN_(3)∶Eu^(2+) Mn^(2+) red phosphor
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CoS_(2)/S-Doped C with In Situ Constructing Heterojunction Structure for Boosted K-lon Diffusion and Highly Efficient Storage
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作者 Zhipeng Zhao Xiangdong Pei +6 位作者 Jiang Li Yanchao Qin Chuanqi Li Jingyun Cheng Yongzhu Fu Xin Du Dan Li 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第6期402-408,共7页
Exploring the desired anode materials to address the issues of poor structural stability tardy redox kinetics caused by large potassium ionic radius are fatal for the realization of large-scale applications of potassi... Exploring the desired anode materials to address the issues of poor structural stability tardy redox kinetics caused by large potassium ionic radius are fatal for the realization of large-scale applications of potassium-ion batteries.In this work,the feasibility to achieve promoted K^(+)storage by constructing the model of CoS_(2)enfolded in carbon was verified by the density functional theory calculations.And the results predicted a faster electron/potassium ion transport kinetics than bare CoS_(2)by increasing electron carrier density and narrowing diffusion barrier.Therefore,an interfacial engineering strategy was applied and implemented to synthesize the CoS_(2)nanoparticles enveloped in the S-doped carbon(CoS_(2)/SC)under this inspiration.The as-prepared CoS_(2)/SC composite exhibited a prominent rate capability and long cycling lifespan,delivering the high capacity of 375 mA h g^(-1)at 0.2 A g^(-1)at the 100th cycle and 273 mA h g^(-1)at 2 A g^(-1)over 300 cycles.The in/ex situ characterizations unraveled the converse mechanism of CoS_(2)/SC in K^(+)storage,showing an eventually reversible phase transformation of K_(x)CoS_(2)Co↔within the electrochemical reactions. 展开更多
关键词 anode cos_(2) DFT calculation fast ion transport potassium-ion batteries
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A dendritic Cu/Cu_(2)O structure with high curvature enables rapid and efficient reduction of carbon dioxide to C_(2) in an H-cell
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作者 Lei shao Bochen Hu +3 位作者 Jinhui Hao Junjie Jin Weidong Shi Min Chen 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期144-153,共10页
Electrocatalytic reduction of CO_(2)(CO_(2)RR)to multicarbon products is an efficient approach for ad-dressing the energy crisis and achieving carbon neutrality.In H-cells,achieving high-current C_(2)products is chall... Electrocatalytic reduction of CO_(2)(CO_(2)RR)to multicarbon products is an efficient approach for ad-dressing the energy crisis and achieving carbon neutrality.In H-cells,achieving high-current C_(2)products is challenging because of the inefficient mass transfer of the catalyst and the presence of the hydrogen evolution reaction(HER).In this study,dendritic Cu/Cu_(2)O with abundant Cu^(0)/Cu^(+)interfaces and numerous dendritic curves was synthesized in a CO_(2)atmosphere,resulting in the high selectivity and current density of the C_(2)products.Dendritic Cu/Cu_(2)O achieved a C_(2)Faradaic efficiency of 69.8%and a C_(2)partial current density of 129.5 mA cm^(-2)in an H-cell.Finite element simulations showed that a dendritic structure with a high curvature generates a strong electric field,leading to a localized CO_(2)concentration.Additionally,DRT analysis showed that a dendritic struc-ture with a high curvature actively adsorbed the surrounding high concentration of CO_(2),enhancing the mass transfer rate and achieving a high current density.During the experiment,the impact of the electronic structure on the performance of the catalyst was investigated by varying the atomic ratio of Cu^(0)/Cu^(+) on the catalyst surface,which resulted in improved ethylene selectivity.Under the optimal atomic ratio of Cu^(0)/Cu^(+),the charge transfer resistance was minimized,and the desorption rate of the intermediates was low,favoring C_(2) generation.Density functional theory calculations indicated that the Cu^(0)/Cu^(+) interfaces exhibited a lower Gibbs free energy for the rate-determining step,enhancing C_(2)H_(4) formation.The Cu/Cu_(2)O catalyst also exhibited a low Cu d-band center,which enhanced the adsorption stability of *CO on the surface and facilitated C_(2)formation.This observa-tion explained the higher yield of C_(2) products at the Cu^(0)/Cu^(+) interface than that of H_(2) under rapid mass transfer.The results of the net present value model showed that the H-cell holds promising industrial prospects,contingent upon it being a catalyst with both high selectivity and high current density.This approach of integrating the structure and composition provides new insights for ad-vancing the CO_(2)RR towards high-current C_(2) products. 展开更多
关键词 Reduction of CO_(2) High current Dendritic structure Cu/Cu_(2)O H-cell
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Role of renin-angiotensin system/angiotensin converting enzyme-2 mechanism and enhanced COVID-19 susceptibility in type 2 diabetes mellitus 被引量:1
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作者 Ashwin Kumar Shukla Komal Awasthi +1 位作者 Kauser Usman Monisha Banerjee 《World Journal of Diabetes》 SCIE 2024年第4期606-622,共17页
Coronavirus disease 2019(COVID-19)is a disease that caused a global pandemic and is caused by infection of severe acute respiratory syndrome coronavirus 2 virus.It has affected over 768 million people worldwide,result... Coronavirus disease 2019(COVID-19)is a disease that caused a global pandemic and is caused by infection of severe acute respiratory syndrome coronavirus 2 virus.It has affected over 768 million people worldwide,resulting in approx-imately 6900000 deaths.High-risk groups,identified by the Centers for Disease Control and Prevention,include individuals with conditions like type 2 diabetes mellitus(T2DM),obesity,chronic lung disease,serious heart conditions,and chronic kidney disease.Research indicates that those with T2DM face a hei-ghtened susceptibility to COVID-19 and increased mortality compared to non-diabetic individuals.Examining the renin-angiotensin system(RAS),a vital regulator of blood pressure and pulmonary stability,reveals the significance of the angiotensin-converting enzyme(ACE)and ACE2 enzymes.ACE converts angiotensin-I to the vasoconstrictor angiotensin-II,while ACE2 counters this by converting angiotensin-II to angiotensin 1-7,a vasodilator.Reduced ACE2 exp-ression,common in diabetes,intensifies RAS activity,contributing to conditions like inflammation and fibrosis.Although ACE inhibitors and angiotensin receptor blockers can be therapeutically beneficial by increasing ACE2 levels,concerns arise regarding the potential elevation of ACE2 receptors on cell membranes,potentially facilitating COVID-19 entry.This review explored the role of the RAS/ACE2 mechanism in amplifying severe acute respiratory syndrome cor-onavirus 2 infection and associated complications in T2DM.Potential treatment strategies,including recombinant human ACE2 therapy,broad-spectrum antiviral drugs,and epigenetic signature detection,are discussed as promising avenues in the battle against this pandemic. 展开更多
关键词 Angiotensin-converting enzyme 2 Angiotensin-converting enzyme inhibitors Angiotensin-II receptor blockers Complex diseases COVID-19 Type 2 diabetes
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Automatic modulation recognition of radio fuzes using a DR2D-based adaptive denoising method and textural feature extraction 被引量:1
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作者 Yangtian Liu Xiaopeng Yan +2 位作者 Qiang Liu Tai An Jian Dai 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期328-338,共11页
The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-n... The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-noise ratio(SNR)of such environments is usually low,which makes it difficult to implement accurate recognition of radio fuzes.To solve the above problem,a radio fuze automatic modulation recognition(AMR)method for low-SNR environments is proposed.First,an adaptive denoising algorithm based on data rearrangement and the two-dimensional(2D)fast Fourier transform(FFT)(DR2D)is used to reduce the noise of the intercepted radio fuze intermediate frequency(IF)signal.Then,the textural features of the denoised IF signal rearranged data matrix are extracted from the statistical indicator vectors of gray-level cooccurrence matrices(GLCMs),and support vector machines(SVMs)are used for classification.The DR2D-based adaptive denoising algorithm achieves an average correlation coefficient of more than 0.76 for ten fuze types under SNRs of-10 d B and above,which is higher than that of other typical algorithms.The trained SVM classification model achieves an average recognition accuracy of more than 96%on seven modulation types and recognition accuracies of more than 94%on each modulation type under SNRs of-12 d B and above,which represents a good AMR performance of radio fuzes under low SNRs. 展开更多
关键词 Automatic modulation recognition Adaptive denoising Data rearrangement and the 2D FFT(DR2D) Radio fuze
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Detection of SARS-CoV-2 and Its Mutated Variants Using RT-LAMP-CRISPR-Cas12a Platform
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作者 WANG Shanshan YAN Jun +8 位作者 DU Tongtong LIU Luo CHEN Xiong HAN Song YIN Jun PENG Biwen HE Xiaohua LU Xuan LIU Wanhong 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2024年第5期453-460,共8页
The global outbreak of coronavirus disease 19(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-Co V-2),has raised significant global apprehension.Developing a rapid,efficient,sensitive,and accu... The global outbreak of coronavirus disease 19(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-Co V-2),has raised significant global apprehension.Developing a rapid,efficient,sensitive,and accurate point-of-care detection method is imperative for curbing SARS-Co V-2 transmission.Here,we screened a sequence,designed a set of highly sensitive loopmediated isothermal amplification primers(LAMP)and g RNA,and developed a user-friendly detection platform combining CRISPRCas12a and RT-LAMP technology to specifically detect SARS-Co V-2 and its 5 variants.Bioinformatics analysis and Cas12a-g RNA identification ensured sequence specificity,allowing us to identify SARS-Co V-2 mutations.We developed a method for the detection of SARSCoV-2 using these primers in combination with LAMP amplification and CRISPR-Cas12a technology.This method is designed to detect SARS-CoV-2(NC_045512),Alpha(B.1.1.7),Beta(B.1.351),Gamma(P.1),Delta(B.1.617.2)and Omicron(B.1.1.529).Additionally,it can differentiate SARS-CoV-2 from other coronaviruses.Quantitative analysis can be conducted by measuring fluorescence values,while qualitative analysis can be performed by observing fluorescence color point-of-care diagnosis changes with the naked eye.These results suggest that a set of novel sensitive LAMP primers and g RNA have been obtained to detect the extensive variants,and the RT-LAMPCRISPR-Cas12a platform significantly facilitates point-of-care diagnosis,thereby halting the spread of SARS-Co V-2,thus contributing to COVID-19 prevention and control. 展开更多
关键词 SARS-CoV-2 mutation CRISPR RT-LAMP point-of-care diagnosis
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