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Total flavonoids of Astragalus membranaceus protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity in mice by inhibiting ferroptosis through SLC7A11/GPX-4 signaling pathway 被引量:1
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作者 Zitian Gao Gaorui Wang +6 位作者 Yujie Chen Wuke Yuan jun cai Aiping Feng Jie Fang Qi Xu Xiaojun Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期414-420,共7页
Parkinson’s disease(PD)is a common neurodegenerative disorder with no cure.Astragalus membranaceus is used in Chinese culture as a food supplement to boost immunity.The present study aimed to explore the neuroprotect... Parkinson’s disease(PD)is a common neurodegenerative disorder with no cure.Astragalus membranaceus is used in Chinese culture as a food supplement to boost immunity.The present study aimed to explore the neuroprotective effects of total flavonoids extracted from A.membranaceus(TFA)and their protective mechanisms.TFA offered neuroprotection against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)in the mouse model of Parkinsonism,by improving behavior performance in the gait analysis and pole test,and inhibiting the decline of tyrosine hydroxylase(TH)positive neurons and TH protein expression in substantia nigra of mice.TFA also prevented 1-methyl-4-phenylpyridinium(MPP+)induced neurotoxicity in SHSY5Y cells,by increasing GSH and GSH/GSSG ratio,and reducing reactive oxygen species.In addition,the neuroprotective effects of TFA were associated with its ability to restore MPTP/MPP+induced downregulation of SLC7A11 and glutathione peroxidase 4(GPX-4).In conclusion,we demonstrated that TFA exerted significant neuroprotection against MPTP/MPP+induced neurodegeneration by inhibiting ferroptosis through the regulation of SLC7A11/GPX-4 axis,suggesting the use of TFA as a possible food supplement in the prevention of PD. 展开更多
关键词 Parkinson’s disease Total fl avonoids of Astragalus membranaceus Ferroptosis SLC7A11
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20mm厚AZ31镁合金厚板搅拌摩擦焊接接头的显微组织演变及强化机制
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作者 刘强 王文 +7 位作者 彭湃 张婷 韩鹏 关肖虎 王智 乔柯 蔡军 王快社 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第11期3295-3308,共14页
采用搅拌摩擦焊焊接20mm厚AZ31镁合金板材,并沿厚度方向分5层对接头的显微组织和力学性能进行表征。结果表明:焊接温度和温降速率的不同导致搅拌区晶粒尺寸不均匀,且在材料流动行为的作用下,接头不同区域形成不同强织构。此外,接头各层... 采用搅拌摩擦焊焊接20mm厚AZ31镁合金板材,并沿厚度方向分5层对接头的显微组织和力学性能进行表征。结果表明:焊接温度和温降速率的不同导致搅拌区晶粒尺寸不均匀,且在材料流动行为的作用下,接头不同区域形成不同强织构。此外,接头各层的屈服强度和抗拉强度从上表面至下表面整体呈逐渐增加的趋势,伸长率沿接头厚度方向首先由9.5%升高至10.5%,然后逐渐降低至6.0%。整体接头的抗拉强度达到母材的88.5%。接头的主要强化机制为细晶强化。 展开更多
关键词 显微组织演变 力学性能 强化机制 搅拌摩擦焊 镁合金 厚板
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冷喷摩擦复合增材制造6061铝合金的显微组织、力学性能和腐蚀行为
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作者 刘志浩 韩鹏 +8 位作者 王文 关肖虎 王智 方园 乔柯 叶东明 蔡军 谢迎春 王快社 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第11期3250-3265,共16页
采用冷喷摩擦复合增材制造(CFAM)技术制备6061铝合金块体材料。采用OM、SEM和EBSD对冷喷涂(CS)和CFAM试样的显微组织进行表征,通过显微硬度、拉伸和腐蚀实验研究两者的力学性能和腐蚀行为。结果表明,与CS试样相比,CFAM试样的显微组织更... 采用冷喷摩擦复合增材制造(CFAM)技术制备6061铝合金块体材料。采用OM、SEM和EBSD对冷喷涂(CS)和CFAM试样的显微组织进行表征,通过显微硬度、拉伸和腐蚀实验研究两者的力学性能和腐蚀行为。结果表明,与CS试样相比,CFAM试样的显微组织更加致密和均匀,晶粒细小等轴,平均晶粒尺寸为3.1μm,显微硬度、极限抗拉强度和伸长率分别提高了22%、171%和683%。CFAM试样的腐蚀电流密度比CS试样低95.1%~97.8%,腐蚀机理由CS试样的点腐蚀转变为晶间腐蚀。 展开更多
关键词 冷喷摩擦复合增材制造 6061铝合金 显微组织 力学性能 腐蚀机理
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Local-State Routing in Satellite Constellation Networks from the Perspective of Complex Network
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作者 Xin Xu jun cai +2 位作者 Aijun Liu Chaoying Dong Chen Han 《China Communications》 SCIE CSCD 2023年第7期72-88,共17页
Routing algorithms in satellite constellation networks usually make use of the local state information to adapt to the topology and traffic dynamics,since it’s difficult to obtain the global states in time due to the... Routing algorithms in satellite constellation networks usually make use of the local state information to adapt to the topology and traffic dynamics,since it’s difficult to obtain the global states in time due to the spatial large-scale feature of constellation networks.Furthermore,they use different range of local states and give these states distinct weights.However,the behind design criterion is ambiguous and often based on experience.This paper discusses the problem from the perspective of complex network.A universal local-state routing model with tunable parameters is presented to generalize the common characteristics of local-state routing algorithms for satellite constellation networks.Based on this,the impacts of localstate routing algorithms on performance and the correlation between routing and traffic dynamics are analyzed in detail.Among them,the tunable parameters,the congestion propagation process,the critical packet sending rate,and the network robustness are discussed respectively.Experimental results show that routing algorithms can achieve a satisfactory performance by maintaining a limited state awareness capability and obtaining the states in a range below the average path length.This provides a valuable design basis for routing algorithms in satellite constellation networks. 展开更多
关键词 satellite constellation local state routing traffic dynamics complex networks ROBUSTNESS
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Biomarkers Associated with Radiation-Induced Lung Injury in Cancer Patients
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作者 Yuan-Yuan Chen Dong-Xu Ao +1 位作者 Chen-Yang Zuo jun cai 《Journal of Biosciences and Medicines》 2023年第10期209-224,共16页
Radiotherapy (RT) is a common and effective non-surgical treatment for thoracic solid tumors, and radiation-induced lung injury (RILI) is the most common side effect of radiotherapy. Even if RT is effective in the tre... Radiotherapy (RT) is a common and effective non-surgical treatment for thoracic solid tumors, and radiation-induced lung injury (RILI) is the most common side effect of radiotherapy. Even if RT is effective in the treatment of cancer patients, severe radiation pneumonitis (RP) or pulmonary fibrosis (PF) can reduce the quality of life of patients and may even lead to serious consequences of death. Therefore, how to overcome the problem of accurate prediction and early diagnosis of RT for pulmonary toxicity is very important. This review summarizes the related factors of RILI and the related biomarkers for early prediction of RILI. 展开更多
关键词 Radiation Induced Lung Injury RILI FIBROSIS Biomarkers
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Cr掺杂ZnO(1010)表面的原子结构和电子性质研究 被引量:1
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作者 黄武根 蔡军 +3 位作者 胡俊 朱俊发 杨帆 包信和 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第6期971-979,共9页
多相催化中ZnO基催化剂广泛应用于甲醇合成、水汽变换和合成气转化等诸多领域.近期发展的ZnCrO_(x)-分子筛双功能催化剂(OX-ZEO)打破了传统合成气转化的ASF分布,能够高选择性地实现CO加氢转化为低碳烯烃.其中CO在ZnCrO_(x)表面活化被认... 多相催化中ZnO基催化剂广泛应用于甲醇合成、水汽变换和合成气转化等诸多领域.近期发展的ZnCrO_(x)-分子筛双功能催化剂(OX-ZEO)打破了传统合成气转化的ASF分布,能够高选择性地实现CO加氢转化为低碳烯烃.其中CO在ZnCrO_(x)表面活化被认为是OX-ZEO催化的关键基元过程,但是ZnCrO_(x)表面的活性位组成和结构目前仍然缺乏原子尺度上的理解,阻碍了人们对反应机理的研究.因此,本文构建了Cr掺杂ZnO(1010)单晶的模型催化剂,结合低温扫描隧道显微镜(LT-STM)和X射线光电子能谱(XPS),研究不同条件下Cr在ZnO(1010)表面生长的形貌结构,并重点考察了Cr掺杂对表面电子结构和CO吸附的影响.ZnO(101–0)是Zn-O混合终止的非极性面,也是ZnO最稳定的晶面.实验发现室温下沉积Cr在ZnO(1010)表面时,出现多种生长结构.STM显示低覆盖度(<0.1 ML)的沉积Cr在ZnO(1010)台阶面上出现单分散的亮点和暗点,分别为位于表面O原子链上的Cr原子和嵌入ZnO晶格替代Zn^(2+)的Cr.XPS显示这些Cr原子与ZnO之间存在电荷转移,呈现出+3价.由于Cr在[0001]方向扩散能垒高于沿着[1210]方向扩散的能垒,能够观察到少量沿着[0001]台阶方向生长的长方形岛,归属为Cr岛.表面单分散Cr原子和Cr岛的密度都会随着Cr沉积量的增加而增多.当在200 K沉积Cr来抑制Cr的表面扩散行为,我们发现Cr主要在ZnO面上形成Cr团簇,均匀分散在表面;而在400 K沉积时,Cr则直接扩散进入ZnO晶格.STM和XPS结果都表明,600 K以上的高温处理能够促进Cr进入ZnO晶格,同时伴随Cr岛的分解,这说明表面负载的Cr原子在高温不能稳定存在;而Cr岛的再分散进入到近表层甚至体相,也表明了Cr和ZnO之间的强相互作用.这种强相互作用有利于Cr在ZnO表层进行原子级分散,形成具有催化活性的结构;与此同时,实验发现Cr扩散到近表层会导致表面能带向上弯曲,从而导致XPS芯能级向低结合能位移.在超高真空条件下,CO与Cr掺杂的ZnO表面作用较弱,室温下只观察到碳酸盐的形成.因此,通过对比不同条件下Cr在ZnO(1010)表面的生长结构,热稳定性以及相应的电子结构变化,发现Cr和ZnO存在强相互作用,在600 K以上Cr以Cr^(3+)形式分散到ZnO晶格中.本文通过构建Cr/ZnO(1010)模型催化剂,并研究其原子结构与电子结构的演变,为进一步的分子尺度合成气转化机理研究开辟了道路. 展开更多
关键词 ZNO Cr/ZnO(1010)催化剂 CO吸附 STM XPS
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利用交流阻抗谱揭示Ir(111)电极在酸性溶液中的氢吸附动力学 被引量:1
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作者 唐延丽 陈微 +3 位作者 许绵乐 韦臻 蔡俊 陈艳霞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第2期179-187,I0001,共10页
本文利用阻抗谱研究Ir(111)电极在HClO_(4)和H_(2)SO_(4)中溶液中的氢吸附行为.在HClO_(4)溶液中,随着施加电位从0.2 V降到0.1 V(vs RHE),Ir(111)电极上氢吸附速率从1.74×10^(-8)mol·cm^(-2)·s^(-1)增大到3.47×10^(... 本文利用阻抗谱研究Ir(111)电极在HClO_(4)和H_(2)SO_(4)中溶液中的氢吸附行为.在HClO_(4)溶液中,随着施加电位从0.2 V降到0.1 V(vs RHE),Ir(111)电极上氢吸附速率从1.74×10^(-8)mol·cm^(-2)·s^(-1)增大到3.47×10^(-7)mol·cm^(-2)·s^(-1).与相同条件下Pt(111)电极上的氢吸附速率相比,Ir(111)上的氢吸附速率要小1~2个数量级,这是由于Ir(111)电极与H_(2)O结合能力更强,因此位于水合氢键网络中的氢离子需要克服更高的能垒才能重新定向进而发生欠电位沉积.在H_(2)SO_(4)溶液中,氢吸附电位负移了200 mV,吸附速率也下降了一个数量级,这是由于Ir(111)电极表面强吸附的硫酸根/硫酸氢根物种的阻碍作用.结果表明,在电化学环境下,位于电极表面附近的水分子的取代和重新定向在很大程度上影响了氢吸附过程. 展开更多
关键词 氢吸脱附 电化学阻抗谱 Ir(111)电极 硫酸根吸脱附
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Au(111)上过氧化氢在碱性介质中氧化反应的pH效应(英文) 被引量:1
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作者 李皎皎 魏杰 +1 位作者 蔡俊 陈艳霞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第6期779-783,733,共6页
本文经过系统地研究Au(111)上过氧化氢在pH值从10到13的不同碱性溶液体系中氧化反应(HPOOR),发现随着溶液pH的增大,HPOOR的活性增大,电流电势i-iE极化曲线的斜率减小.HO2-是碱性溶液中HPOOR的主要反应物种,在高pH溶液下有很快的动力学... 本文经过系统地研究Au(111)上过氧化氢在pH值从10到13的不同碱性溶液体系中氧化反应(HPOOR),发现随着溶液pH的增大,HPOOR的活性增大,电流电势i-iE极化曲线的斜率减小.HO2-是碱性溶液中HPOOR的主要反应物种,在高pH溶液下有很快的动力学反应主要是由于电极表面的正电荷与体系中的阴离子HO2-和OH-等有静电相互作用的原因.因此在溶液反应物随pH增大的时候,热力学的驱动力也加快了HO2-的氧化过程. 展开更多
关键词 H2O2的氧化反应 Au(111)电极 PH效应 静电相互作用
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Efficient generation of hepatocyte-like cells from human induced pluripotent stem cells 被引量:64
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作者 Zhihua Song jun cai +13 位作者 Yanxia Liu Dongxin Zhao jun Yong Shuguang Duo Xijun Song Yushan Guo Yang Zhao Han Qin Xiaolei Yin Chen Wu Jie Che Shichun Lu Mingxiao Ding Hongkui Deng 《Cell Research》 SCIE CAS CSCD 2009年第11期1233-1242,共10页
人的导致的 pluripotent 茎(iPS ) 房间类似于胚胎的茎(ES ) 房间,和罐头强烈地增殖并且区分进许多房间类型。然而,人的 iPS 房间的肝的区别还没被报导了。在这份报告,人的 iPS 房间被导致由一个逐步的协议区分进肝的房间。肝房间标... 人的导致的 pluripotent 茎(iPS ) 房间类似于胚胎的茎(ES ) 房间,和罐头强烈地增殖并且区分进许多房间类型。然而,人的 iPS 房间的肝的区别还没被报导了。在这份报告,人的 iPS 房间被导致由一个逐步的协议区分进肝的房间。肝房间标记的表达式和人的 iPS 的肝相关的函数导出房间的房间被监视并且与区分的人的 ES 房间和主要人的 hepatocytes 的相比。在白天 7 点的约 60% 区分的人的 iPS 房间表示了肝的标记 alpha fetoprotein 和白长袍的。在白天 21 点的区分的房间包括白朊 Asecretion,肝糖合成,脲生产和可诱导的细胞色素 P450 活动展出了肝房间功能。肝的标记的表示和 iPS 的肝相关的功能导出房间的肝的房间比得上人的 ES 导出房间的肝的房间的。这些结果证明人的 iPS 房间,类似于人的 ES 房间,能高效地被导致区分房间进象 hepatocyte 一样。 展开更多
关键词 人类胚胎干细胞 人肝细胞 诱导分化 多能性 细胞色素P450 细胞分化 基因表达 IPS
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Influence of dexamethasone on inflammatory mediators and NF-κB expression in multiple organs of rats with severe acute pancreatitis 被引量:42
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作者 Xi-Ping Zhang Ling Zhang +5 位作者 Lin-Jie Chen Qi-Hui Cheng Jian-Mei Wang Wei cai Hai-Ping Shen jun cai 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第4期548-556,共9页
AIM: To observe the therapeutic effects of dexamethasone on rats with severe acute pancreatitis (SAP) and investigate the influences of dexamethasone on the inflammatory mediators and NF-κB expression in multiple org... AIM: To observe the therapeutic effects of dexamethasone on rats with severe acute pancreatitis (SAP) and investigate the influences of dexamethasone on the inflammatory mediators and NF-κB expression in multiple organs of SAP rats as well as the mechanisms involved. METHODS: Ninety Sprague-Dawley (SD) rats with SAP were randomly divided into the model group (n = 45) and dexamethasone treatment group (n = 45), and another 45 rats were selected for the sham operation group. All groups were randomly subdivided into the 3 h, 6 h and 12 h groups, each group containing 15 rats. The survival of all groups and pathological changes of multiple organs (liver, kidney and lung) were observed at different time points after the operation. The pathologicalscore of multiple organs was carried out, followed by the determination of amylase, endotoxin and TNF-α contents in blood. The tissue microarray was used to detect the expression levels of NF-κB p65 protein in multiple organs. RESULTS: There was no marked difference between the model group and treatment group in the survival rate. The amylase content of the treatment group was significantly lower compared to the model group at 12 h (P < 0.01, 7791.00 vs 9195.00). Moreover, the endotoxin and TNF-α levels of the treatment group were significantly lower than that of the model group at 6 h and 12 h (P < 0.01, 0.040 vs 0.055, 0.042 vs 0.059 and P < 0.05, 58.30 vs 77.54, 38.70 vs 67.30, respectively). Regarding the changes in liver NF-κB expression, the model group significantly exceeded the sham operation group at 3 h (P < 0.01, 1.00 vs 0.00), and the treatment group significantly exceeded the sham operation group at 12 h (P < 0.01, 1.00 vs 0.00), whereas no marked difference was observed between the model group and treatment group at all time points. The kidney NF-κB expression level in the treatment group significantly exceeded the model group (P < 0.05, 2.00 vs 0.00) and the sham operation group (P < 0.01, 2.00 vs 0.00) at 12 h. No NF-κB expression in the lung was found in any group. CONCLUSION: Dexamethasone can lower the amylase, endotoxin and TNF-α levels as well as mortality of SAP rats. NF-κB plays an important role in multiple organ injury. Further studies should be conducted to determine whether dexamethasone can ameliorate the pathological changes of multiple organs by reducing the NF-κB expression in the liver and kidney. The advantages of tissue microarrays in pancreatitis pathological examination include time- and energy- saving, and are highly efficient and representative. The restriction of tissue microarrays on the representation of tissues to various extents due to small diameter may lead to the deviation of analysis. 展开更多
关键词 地塞米松 胰腺炎 治疗方法 抗炎药
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结构明确的Pt基电极在温和电化学条件下的表面重构
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作者 魏杰 陈微 +2 位作者 周达 蔡俊 陈艳霞 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第11期2792-2801,共10页
Pt基材料对众多电催化反应都具有较优异的性能,因此是被广泛研究的一类电催化剂.尤其自20世纪80年代实现在室温室压环境(Clavilier method)制备出结构明确、表面洁净的Pt单晶电极以来,它一直作为最重要的一类模型电极用于揭示电催化反... Pt基材料对众多电催化反应都具有较优异的性能,因此是被广泛研究的一类电催化剂.尤其自20世纪80年代实现在室温室压环境(Clavilier method)制备出结构明确、表面洁净的Pt单晶电极以来,它一直作为最重要的一类模型电极用于揭示电催化反应的结构-性能关系以及机理和动力学.具有明确表面结构的Pt单晶电极在温和的电化学条件下(例如,在双电层、氢的欠电位沉积(H-UPD)或温和的氢析出/氧物种(OH)吸脱附等电位区域)通常被认为是相对稳定的.然而,随着电化学原位显微/光谱技术的进步,在过去的十年中,人们在温和的电化学条件下也观察到了Pt基模型电极表面细微的重构现象.通过产生或破坏高活性位点等,这种细微的表面重构可以显著改变电催化性能,并极大地干扰对结构-性能关系以及相关反应机理的推断,同时也对理论预测与实验测量之间,以及不同环境下的实验测量结果之间的一致性提出了巨大挑战.本文以CO的吸附与氧化、H2吸附与氢析出反应和O_(2)还原等常见的电化学过程为例,总结了在温和电化学反应条件下具有明确表面结构的Pt(基)模型电极表面观察到的一些典型重构现象.这些重构现象可能是导致在多种电催化反应的结构-性能关系研究中理论预测和实验结果之间,以及不同组的实验结果之间存在差异的原因.例如Pt(111)单晶电极上氢气析出反应(HER)的交换电流密度一直存在较大的分歧;理论和实验预测的Pt阶梯晶面在酸性溶液中氧还原反应(ORR)活性顺序彼此矛盾以及CO分子的氧化前峰出现的条件也存在一定争议等等.这些结果也能为其他电催化体系的构效关系研究提供一定启示.此外,本文也强调了在电化学测量之前、期间和之后对电极进行精细结构表征的必要性及其对准确认识相关电催化体系的反应机理、动力学和构效关系的意义,并对多种原位谱学、显微表征技术未来在时间和空间分辨率上的更大进步、耦合联用,在实时反应条件下以前所未有的原子/分子尺度水平建立更准确的构效关系,增强对电催化原理的认识进行了展望. 展开更多
关键词 表面重构 结构明确的Pt电极表面 结构-性能关系 电化学原位表征 电催化
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Pd修饰Cu电极的电化学CO2还原
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作者 孙志娟 Matthew M.Sartin +5 位作者 陈微 贺凡 蔡俊 叶旭旭 路军岭 陈艳霞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第3期303-310,I0002,共9页
利用微分电化学质谱和电化学原位衰减全反射红外光谱技术探究了Cu和CuPd催化剂上CO2和CO的电化学还原行为.红外光谱观察到了生成甲醇、甲烷与乙烯的CHx中间物种.在CuPd电极CO2还原过程中,红外光谱的CO吸附峰起始电位比Cu正移大约300 mV... 利用微分电化学质谱和电化学原位衰减全反射红外光谱技术探究了Cu和CuPd催化剂上CO2和CO的电化学还原行为.红外光谱观察到了生成甲醇、甲烷与乙烯的CHx中间物种.在CuPd电极CO2还原过程中,红外光谱的CO吸附峰起始电位比Cu正移大约300 mV,说明CuPd能够有效促进CO2还原;CO饱和溶液中,Cu和CuPd电极CO起始吸附电位基本相同;两电极上CO谱带出现的电位与CO3^2-的谱带降低的电位基本相同,说明C O的吸附需要CO3^2-的脱附.利用电化学在线质谱发现在CuPd电极上CO还原产生CH4和CH3OH的起始电位比Cu电极正移约200 mV.推测催化活性的提升可能是由于Pd的引入改变了Cu的d能带,且Pd吸附更多的H,从而促进CO2还原,使CO能够与H结合并被深度还原. 展开更多
关键词 CO2还原 CH键 CuPd电极活性 微分电化学质谱 衰减全反射红外光谱
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揭示电极反应的内在动力学:受传质影响下的旋转圆盘电极体系的极限扩散电流合理解析
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作者 许绵乐 陈微 +3 位作者 廖玲文 韦臻 蔡俊 陈艳霞 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第5期797-804,I0012,共9页
旋转圆盘电极体系被广泛用于研究可能因反应物传质不足而受影响的电催化反应动力学.在该体系中,通过Koutecky-Levich方程计算的特定超电势下的动力学电流密度通常用作评价电催化剂活性的指标.然而,普遍发现在文献中没有合理辨析极限扩... 旋转圆盘电极体系被广泛用于研究可能因反应物传质不足而受影响的电催化反应动力学.在该体系中,通过Koutecky-Levich方程计算的特定超电势下的动力学电流密度通常用作评价电催化剂活性的指标.然而,普遍发现在文献中没有合理辨析极限扩散电流密度.相比于动力学电流密度,实验测量的电流密度对极限扩散电流密度进行归一化(电流密度与极限电流的比值j/j)的方法,也经常出现其有效性不合理的情况.本文通过以氧还原反应/氢气氧化反应/氢析出反应为例,证明了从实验数据中合理解析在不同特定的实验条件下同一反应的实际极限扩散电流密度对于准确推导动力学电流密度的方法.分析揭示了归一化电流(j/j)是一个粗略的活性指标,它只能用于定性比较在传质和电极粗糙度因子完全相同的条件下的活性趋势.除此之外,如果用归一化电流此作为活性指标去比较内在的活性,则需要排除浓差超电势的影响. 展开更多
关键词 极限电流 动力学电流 传质 活性指标
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The application of EPICS in TMSR radiation protection and access control system 被引量:8
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作者 Li-Feng Han Yong-Zhong Chen +5 位作者 jun cai Hai-Xia Xu Wen-Bo Huang Ning Zhang Li-Xin Han Peng-Fei Hong 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第2期58-63,共6页
To treat technical problems of data acquisition,alarm management, and historical data archiving of radiation protection control system in Thorium Molten Salt Reactor, a network prototype system was designed based on e... To treat technical problems of data acquisition,alarm management, and historical data archiving of radiation protection control system in Thorium Molten Salt Reactor, a network prototype system was designed based on experimental physics and industrial control system.Radiation level of many locations in Jiading campus of Shanghai Institute of Applied Physics is being continuously monitored, and boundaries of accelerator facilities and radiochemical areas are defined by the access control system. In this paper, we introduce the control system design,including human–machine interfaces, alarm system, historical data archiving system, and the software for access control. The software development followed the standard of Capability Maturity Model Integration(CMMIò) Level3, and the software had passed a third-party test, which indicated that the functionality and the reliability could fulfill the requirements of the radiation protection system. 展开更多
关键词 访问控制系统 辐射防护 应用 能力成熟度模型 史诗 工业控制系统 放射防护 历史数据
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化学在考古学中的跨学科应用:使用手持式X射线荧光光谱仪鉴定唐代血经主要元素成分 被引量:1
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作者 蔡军 李文 +1 位作者 史梅 胡文兵 《大学化学》 CAS 2022年第12期217-225,共9页
采用手持式X射线荧光光谱仪(pXRF)现场无损对照检测了南京大学博物馆收藏的国家一级文物敦煌莫高窟出土唐人写本《大方便佛报恩经残卷》朱书和血书字迹主要重金属元素成分。通过检测字迹中汞元素和铁元素相对含量多少,结合颜色深浅,鉴... 采用手持式X射线荧光光谱仪(pXRF)现场无损对照检测了南京大学博物馆收藏的国家一级文物敦煌莫高窟出土唐人写本《大方便佛报恩经残卷》朱书和血书字迹主要重金属元素成分。通过检测字迹中汞元素和铁元素相对含量多少,结合颜色深浅,鉴定血书中的浅色字迹含有较为丰富的铁元素,应为血液成分所带来。我们首先使用pXRF测试了古代常用红色颜料主要成分含汞元素的朱砂粉、含铁元素的三氧化二铁、两者50:50和99:1混合物浸迹以及动物干血迹中汞元素和铁元素的含量,对照X射线能谱仪(EDX)结果证明pXRF对朱砂中汞元素和铁元素都有很好的检测响应,即使血迹中微量的铁元素也能很清晰地检测出来。我们随后使用pXRF对馆藏的朱书和血书中的字迹对照颜色进行元素相对含量分析,结果显示朱书的字迹普遍颜色较深,主要成分为朱砂;血书中大部分颜色较浅的字迹主要成分为血和朱砂的混合物,而血书中少部分颜色较深的字迹则是由朱砂为主要成分的颜料修补所致。本文为现场无损鉴定成书时间较长的文物血经提供了一种较为可靠的原位无损检测化学方法,可以作为大学化学知识跨学科应用的一个课堂讲解例子。 展开更多
关键词 血经 化学元素鉴定 便携式X射线荧光光谱仪(pXRF)
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中药治疗新冠病毒肺炎的科学基础 被引量:10
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作者 梁丽娴 潘胡丹 +6 位作者 黄虞枫 范星星 王婉莹 何芳 蔡俊 周华 刘良 《Engineering》 SCIE EI 2020年第10期1240-1249,共10页
新近暴发的新冠病毒肺炎(COVID-19)已成为危害全球健康的紧急事件。现有证据表明,新冠病毒(SARS-CoV-2)与其他冠状病毒(如SARS-CoV和MERS-CoV)的基因序列具有相似性。因此,针对现存冠状病毒的引发疾病的机制研究和在治疗SARS时所取得的... 新近暴发的新冠病毒肺炎(COVID-19)已成为危害全球健康的紧急事件。现有证据表明,新冠病毒(SARS-CoV-2)与其他冠状病毒(如SARS-CoV和MERS-CoV)的基因序列具有相似性。因此,针对现存冠状病毒的引发疾病的机制研究和在治疗SARS时所取得的经验和教训,可咨今天对抗新冠病毒引发疾病的参考。COVID-19患者的临床病理特征提示患者在病情进展过程中通常会经历五个发展阶段:大量病毒感染、免疫系统抑制、细胞因子风暴、多器官损伤及后期的肺纤维化样改变,严重者常导致死亡。早期阻断疾病进展是取得治疗成功的关键。但是,目前尚无针对COVID-19的特效药物或疫苗,世界卫生组织(WHO)正敦促尽快建立新型预防和治疗策略。传统中医药(TCM)对于疫病的防治的实践已经积累了几千年的有用经验,它通过整体调节机体功能发挥疗效。在此次疫情中,中医药作为替代治疗或与西药联合使用,在疫情防控中发挥了重要的作用。本文总结了此次抗疫过程中中国国家和省级机构推荐使用的中药复方和中成药的潜在用途和治疗机制,以期发现其治疗COVID-19的潜在科学内涵。同时,整合应用多种组学及转化医学技术开展基础与临床研究有望进一步证实中药复方的治疗机制。 展开更多
关键词 COVID-19 SARS-CoV-2 中药 抗病毒 细胞因子风暴 肺纤维化
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2019 Chinese guideline for the management of hypertension in the elderly 被引量:14
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作者 Qi HUA +16 位作者 Li FAN jun cai Lu-Yuan CHEN Wei-Wei CHEN Ping-Jin GAO Yi-Fang GUO Qing HE Jing LI Nan-Fang LI Wei-Min LI Yue LI Mei-Lin LIU Ning-Ling SUN Wen WANG Liang-Di XIE Jin-Gang YANG Hong YUAN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2019年第2期67-99,共33页
Table of contents Preamble 1 Introduction 1.1 Class of recommendations and level of evidences 1.2 Definition and categories of hypertension in the elderly 1.3 Current status of epidemiology of hypertension in the elde... Table of contents Preamble 1 Introduction 1.1 Class of recommendations and level of evidences 1.2 Definition and categories of hypertension in the elderly 1.3 Current status of epidemiology of hypertension in the elderly 1.4 The characteristics of hypertension in the elderly. 展开更多
关键词 CLASS DEFINITION CATEGORIES
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Tuberculosis in Takayasu arteritis: a retrospective study in 1105 Chinese patients 被引量:5
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作者 Ying ZHANG Peng FAN +7 位作者 Fang LUO Hui-Min ZHANG Lei SONG Wen-jun MA Hai-Ying WU jun cai Lin-Ping WANG Xian-Liang ZHOU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2019年第8期648-655,共8页
Background Tuberculosis (TB) infection has been reported to have a possible relationship with the occurrence and clinical course of Takayasu arteritis (TA). We aimed to describe the characteristics of TB in a large po... Background Tuberculosis (TB) infection has been reported to have a possible relationship with the occurrence and clinical course of Takayasu arteritis (TA). We aimed to describe the characteristics of TB in a large population of TA patients. Methods We included a total of 1105 patients with TA, who were hospitalized between January 1992 and December 2017. Comparisons of clinical features were made according to the presence of TB. Results Among the 1105 patients, 109 (9.9%) had TB, including 53 patients (48.6%) diagnosed with TB before the onset of TA, 23 (21.1%) with a concurrent diagnosis of TB and TA, and 24 patients (22.0%) who developed TB after TA. Pulmonary TB was the most frequently identified (97 patients, 89.0%). Patients with TB had more frequent involvement of the pulmonary artery and experienced more chest discomfort and constitutional symptoms but had less interventional treatment. Demographic characteristics, comorbid diseases, and use of steroids were similar between patients with and without TB. Conclusions The proportion of Chinese TA patients with TB was not low, and about half of the patients had TB before TA. Pulmonary TB was the most common. Pulmonary artery involvement and pulmonary hypertension was more frequent in TA patients with TB. 展开更多
关键词 IMMUNOSUPPRESSIVE agents MYCOBACTERIUM TUBERCULOSIS Pulmonary ARTERY TAKAYASU ARTERITIS
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Mixed adenoneuroendocrine carcinoma of the ampulla:Two case reports 被引量:5
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作者 Zhen Huang Wei-Dong Xiao +3 位作者 Yong Li Song Huang jun cai Jian Ao 《World Journal of Gastroenterology》 SCIE CAS 2015年第7期2254-2259,共6页
Mixed adenoneuroendocrine carcinoma(MANEC)is a malignant tumor with adenocarcinoma and neuroendocrine components,with≥30%of each component required.MANEC of the ampulla is rare.To the best of our knowledge,only 15 ca... Mixed adenoneuroendocrine carcinoma(MANEC)is a malignant tumor with adenocarcinoma and neuroendocrine components,with≥30%of each component required.MANEC of the ampulla is rare.To the best of our knowledge,only 15 cases of MANEC of the ampulla have been reported in the English-language literature.Here,we report two cases of MANEC of the ampulla in two womenaged 43 and 60 years,which was confirmed by histology after pancreaticoduodenectomy.These tumors contained neuroendocrine and adenocarcinoma components.The neuroendocrine components were positive for chromogranin A(Cg A),synaptophysin(Syn)and CD56 by immunostaining.The adenocarcinoma components were negative for Cg A,Syn and CD56.Both cases were T3N0M0(StageⅢA).They survived for 15 and 20 mo after surgery,respectively.A brief discussion about the histopathological features,clinical behavior and treatment of MANEC of ampulla,and review of the relevant literature are presented. 展开更多
关键词 NEUROENDOCRINE TUMOR MIXED adenoneuroendocrine CAR
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The association between orthostatic blood pressure changes and subclinical target organ damage in subjects over 60 years old 被引量:5
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作者 Hong-Jie CHI Hai-jun FENG +7 位作者 Xiao-Jiao CHEN Xiao-Tao ZHAO En-Xiang ZHANG Yi-Fan FAN Xian-Chen MENG Jiu-Chang ZHONG Shou-Ling WU jun cai 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2019年第5期387-394,共8页
Background Although recent studies have indicated that both orthostatic hypotension and orthostatic hypertension independently predict cardiovascular events,the underlying mechanisms are still controversial.The aim of... Background Although recent studies have indicated that both orthostatic hypotension and orthostatic hypertension independently predict cardiovascular events,the underlying mechanisms are still controversial.The aim of the study was to investigate the relationships between orthostatic changes and organ damage in subjects over 60 years old.Methods This is a prospective observational cohort study.One thousand nine hundred and ninety-seven subjects over 60 years old were enrolled.Participants were grouped according to whether they had a drop>20 mmHg in systolic or>10 mmHg in diastolic BP(orthostatic hypotension),an increase in mean orthostatic systolic blood pressure>20 mm Hg(orthostatic hypertension),or normal changes within 3 min of orthostatism.Multiple regression modeling was used to investigate the relationship between orthostatic hypotension,orthostatic hypertension and subclinical organ damage with adjustment for confounders.Results Orthostatic hypotension and orthostatic hypertension were found in 461(23.1%)and 189(9.5%)participants,respectively.Measurement of carotid intima-media thickness(IMT),brachial-ankle pulse wave velocity(baPWV),clearance of creatinine,and microalbuminuria were associated with orthostatic hypotension;measurement of IMT and baPWV were associated with orthostatic hypertension in a cruse model.After adjustment,IMT[odds ratio(OR),95%confidence interval(CI)per one-SD increment:1.385,1.052-1.823;P=0.02],baPWV(OR=1.627,95%CI:1.041-2.544;P=0.033)and microalbuminuria(OR=1.401,95%CI:1.002-1.958;P=0.049)were still associated with orthostatic hypotension,while orthostatic hypertension was only associated with IMT(OR=1.730,95%CI:1.143-2.618;P=0.009).Conclusions Orthostatic hypotension seems to be independently correlated with increased carotid atherosclerosis,arterial stiffness and renal damage in subjects over 60 years old.Orthostatic hypertension correlates with carotid atherosclerosis only. 展开更多
关键词 ATHEROSCLEROSIS BLOOD pressure ORTHOSTATIC ORGAN damage
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