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一例整合了三联吡啶钌和卟啉锌的金属-有机框架材料用于光催化二氧化碳还原全反应
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作者 陈慧滢 朱浩林 +1 位作者 廖培钦 陈小明 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第4期4-10,共7页
利用源源不断的太阳能,将CO_(2)和水转化为增值化学品,是缓解温室效应与能源危机的一种有前途的方法。由于催化体系中的不同功能性部分难以实现氧化与还原反应的耦合,使用水作为还原剂实现光催化CO_(2)还原是一项具有挑战性的工作。金... 利用源源不断的太阳能,将CO_(2)和水转化为增值化学品,是缓解温室效应与能源危机的一种有前途的方法。由于催化体系中的不同功能性部分难以实现氧化与还原反应的耦合,使用水作为还原剂实现光催化CO_(2)还原是一项具有挑战性的工作。金属有机框架(metal-organic framework,MOF)由于其较大的比表面积、多样化的活性位点和结构可调性,是CO_(2)光催化还原全反应的良好备选材料。本文中,我们首先整合了具有光活性的锌(Ⅱ)卟啉基元与联吡啶钌(Ⅱ)基元,构建了一种MOF光催化剂,记作PCN-224(Zn)-Bpy(Ru)。为了进行比较,还合成了两种仅具有锌(Ⅱ)卟啉或联吡啶钌(Ⅱ)基元的同构MOF,分别记作PCN-224(Zn)-Bpy和PCN-224-Bpy(Ru)。由测试结果可知,PCN-224(Zn)-Bpy(Ru)在乙腈和水混合溶液中表现出对CO_(2)还原可观的光催化活性(CO产率为7.6μmol·g^(-1)·h^(-1)),无需额外添加助催化剂、光敏剂或牺牲剂。通过质谱仪观测到^(13)CO(m/z=29)、^(13)C^(18)O(m/z=31)、^(16)O^(18)O(m/z=34)和^(18)O_(2)(m/z=36)信号,表明CO_(2)和H_(2)O分别作为CO和O_(2)的碳源和氧源,这进一步证实了光催化CO_(2)还原与H_(2)O氧化的耦合。然而,在相同条件下对PCN-224-Bpy(Ru)与PCN-224(Zn)-Bpy的光催化性能进行测试,CO产率分别仅为1.5与0μmol·g^(-1)·h^(-1)。机理研究表明,PCN-224(Zn)-Bpy(Ru)的最低未占据分子轨道(LUMO)电位比CO_(2)/CO的氧化还原电位更负,而最高占据分子轨道(HOMO)电位比H_(2)O/O_(2)的氧化还原电位更正,在热力学上满足了光催化CO_(2)还原全反应的要求。相比之下,不含联吡啶钌(Ⅱ)基元的PCN-224(Zn)-Bpy的HOMO电位更负于H_(2)O/O_(2)的氧化还原电位,这表明联吡啶钌(Ⅱ)基元在热力学上是光催化CO_(2)还原全反应所必需的。此外,光致发光光谱中,荧光几乎被PCN-224(Zn)-Bpy(Ru)猝灭,且平均光致发光寿命比PCN-224(Zn)-Bpy和PCN-224-Bpy(Ru)更长,这表明PCN-224中光生载流子的复合率较低。与PCN-224(Zn)-Bpy和PCN-224-Bpy(Ru)相比,PCN-224的光电流更高,这一现象也支持了中后者光生载流子的复合率较低这一结论。总而言之,在光催化CO_(2)还原过程中,锌卟啉(Ⅱ)配体既作为光敏单元,又作为CO_(2)还原活性位点,而联吡啶钌(Ⅱ)基元与锌(Ⅱ)卟啉基元的结合可以优化光催化剂的能带结构,进而促进光催化CO_(2)还原与H_(2)O氧化的耦合,从而实现了高效光催化CO_(2)还原全反应。 展开更多
关键词 金属有机框架 锌(Ⅱ)卟啉衍生物 联吡啶(Ⅱ)钌配合物 光生电荷 光催化CO_(2)还原
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Malignant meningioma with jugular vein invasion and carotid artery extension:A case report and review of the literature 被引量:1
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作者 hui-ying chen Feng Zhao +2 位作者 Jiang-Yuan Qin Hai-Mei Lin Ji-Ping Su 《World Journal of Clinical Cases》 SCIE 2020年第23期6110-6121,共12页
BACKGROUND Grade II and III meningiomas[World Health Organization(WHO)classification]rarely have extracranial metastases via the blood circulation;however,we experienced a case with a metaplastic atypical meningioma a... BACKGROUND Grade II and III meningiomas[World Health Organization(WHO)classification]rarely have extracranial metastases via the blood circulation;however,we experienced a case with a metaplastic atypical meningioma and local dedifferentiation that metastasized to the jugular vein,carotid artery and subclavian artery at the cervicothoracic junction.Such cases have seldom been reported before.CASE SUMMARY The patient was a 30-year-old man who developed right neck masses with dysphagia,labored breathing,dizziness,and occasional earaches.Eight months earlier the patient was diagnosed with a right parietal lobe neoplasm and hemorrhage at a local hospital due to the sudden onset of headaches and left limb weakness,and the post-operative pathology was a metaplastic atypical meningioma(WHO grade II)with local de-differentiation(WHO III).Magnetic resonance imaging revealed a calcified mass at the root of the neck on the right and a large cystic mass in the right parapharyngeal space.Head and neck angiography showed that the right common carotid artery was compressed and completely occluded,and the jugular vein was enveloped by the tumor and occluded.A balloon occlusion test showed no perfusion in the right common carotid artery.Tumor resection,carotid artery ligation,and subclavian artery reconstruction were performed.The tumor was a malignant meningioma.Postoperatively,the patient had Horner's syndrome and hoarseness.CONCLUSION This case highlights the importance of the link between a large cervical mass and a primary intracranial tumor.Malignant meningioma should not be considered merely as an intracranial metastasis spread through cerebrospinal fluid,it can also be transferred through the circulation to the parapharyngeal space and the cervical great vessels. 展开更多
关键词 Malignant meningioma METASTASIS Carotid artery Jugular vein Resection and reconstruction Case report
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Effects of TimeSlips on Cornell Scale for Depression in Dementia scores of senile dementia patients 被引量:1
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作者 hui-ying chen Jing Li +2 位作者 Yan-Ping Wei Ping chen Hong Li 《International Journal of Nursing Sciences》 2016年第1期35-38,共4页
Objective:To investigate the influences of TimeSlips on the Cornell Scale for Depression in Dementia(CSDD)scores of mild or moderate senile dementia patients.Methods:Forty-three cases of mild or moderate senile dement... Objective:To investigate the influences of TimeSlips on the Cornell Scale for Depression in Dementia(CSDD)scores of mild or moderate senile dementia patients.Methods:Forty-three cases of mild or moderate senile dementia patients were selected locally for convenience sake and given the TimeSlips intervention.The patients were assessed using the scales of CSDD and the Observed Emotion Rating Scale(OERS).Results:The differences of the patients'CSDD scores between before and after the intervention were statistically significant(P<0.05).The differences of the patients'OERS scores on positive and negative emotions between before and after the intervention were also statistically significant(P<0.05).Conclusion:TimeSlips is beneficial to relieve depressive symptoms and ameliorate the emotions of mild or moderate senile dementia patients,thus improving their life quality and reducing the burden of their caregivers.A large-scale experimental research on TimeSlips with rigorous design is proposed for further studies. 展开更多
关键词 Aged DEMENTIA Creative expression DEPRESSION
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Leishmania infection and blood sources analysis in Phlebotomus chinensis (Diptera:Psychodidae) along extension region of the loess plateau, China 被引量:1
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作者 Han-Ming chen hui-ying chen +5 位作者 Feng Tao Jing-Peng Gao Kai-Li Li Hua Shi Heng Peng Ya-Jun Ma 《Infectious Diseases of Poverty》 SCIE 2020年第4期108-115,共8页
Background:Visceral leishmaniasis(VL)was one of the most important parasitic diseases in China,caused by Leishmania protozoans and transmitted by sand flies.Recently VL cases have reappeared in China,including the ext... Background:Visceral leishmaniasis(VL)was one of the most important parasitic diseases in China,caused by Leishmania protozoans and transmitted by sand flies.Recently VL cases have reappeared in China,including the extension region of the Loess Plateau.The purpose of this study was to collect fundamental data on the host-vector VL system in the Loess Plateau to assist in the development of prevention and control measures.Methods:Sand flies were collected by light traps from rural areas in Shanxian,Henan,China in 2015,as well as in Wuxiang and Yangquan,Shanxi,China in 2017.The blood sources of sand flies were analyzed by PCR detecting the host-specific mitochondrial cytochrome b(mtDNA cyt b)gene fragments.Leishmania infection in sand flies was detected by amplifying and sequencing ribosomal DNA internal transcribed spacer 1(ITS1).The Leishmania specific antibodies in the sera of local dogs were detected by ELISA kit.Results:Blood sources showed diversity in the extension region of the Loess Plateau,including human,chicken,dog,cattle,pig and goat.Multiple blood sources within a sand fly were observed in samples from Yangquan(17/118,14.4%)and Wuxiang(12/108,11.1%).Leishmania DNA was detected in sand flies collected from Yangquan with minimum infection rate of 1.00%.The ITS1 sequences were conserved with the Leishmania donowni complex.The positive rate of Leishmania specific antibodies in dogs was 5.97%.Conclusions:This study detected the blood sources and Leishmania parasites infection of sand flies by molecular methods in the extension region of Loess Plateau,China.A high epidemic risk of leishmaniasis is currently indicated by the results as the infection of Leishmania in sand flies,the extensive blood sources of sand flies including humans,and positive antibody of Leishmania in local dog sera.Given the recent increase of VL cases,asymptomatic patients,dogs and other potential infected animals should be screened and treated.Furthermore,the density of sand flies needs to be controlled and personal protection should be strengthened. 展开更多
关键词 Sand fly LEISHMANIA BLOOD source EXTENSION REGION of the loess plateau China
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