Photo-generated dinuclear {Eu(II)}2 active sites for selective CO2 reduction in a photosensitizing metal-organic framework

利用太阳光驱动CO2还原不仅可降低大气中CO2浓度，而且可以生成重要的化工原料，是缓解气候变暖和开发新能源的理想途径之一。然而如何制备高效光催化剂将CO2高选择性地转化为高附加值的化学产品极具挑战性。课题组巧妙地将具有催化活性的稀土簇合物与光敏配体组装在一起，合成了具有大孔结构的稀土Eu-Ru(phen)3-MOF催化剂，实现了可见光驱动的CO2到甲酸盐的高效选择性转化。研究表明，该材料光催化生成甲酸盐的反应速率可达到321.9 μmol h−1 mmolMOF−1，这是至今为止报道的光催化还原CO2转化为甲酸盐活性最高的MOFs催化剂。 该项研究工作由博士生闫志浩完成，博士生杜明浩参与部分表征工作；中国科学院大连化学物理研究所金盛烨研究员、刘俊学博士在瞬态光谱表征中给予了支持；我校化学化工学院汪骋教授在数据分析过程中给予大量帮助；理论计算由浙江工业大学庄桂林副教授完成。【Abstract】Photocatalytic reduction of CO2 is a promising approach to achieve solar-to-chemical energy conversion. However, traditional catalysts usually suffer from low efficiency, poor stability, and selectivity. Here we demonstrate that a large porous and stable metal-organic framework featuring dinuclear Eu(Ⅲ)2 clusters as connecting nodes and Ru(phen)3 -derived ligands as linkers is constructed to catalyze visible-light-driven CO2 reduction. Photo-excitation of the metalloligands initiates electron injection into the nodes to generate dinuclear {Eu(Ⅱ)} 2 active sites, which can selectively reduce CO2 to formate in a two-electron process with a remarkable rate of 321.9μmolh −1 mmol MOF −1 . The electron transfer from Ru metalloligands to Eu(Ⅲ)2 catalytic centers are studied via transient absorption and theoretical calculations, shedding light on the photocatalytic mechanism. This work highlights opportunities in photo- generation of highly active lanthanide clusters stabilized in MOFs, which not only enables efficient photocatalysis but also facilitates mechanistic investigation of photo-driven charge separation processes.We are grateful for the financial support from the 973 project (Grant 2014CB845601) of the Ministry of Science and Technology of China, the National Natural Science Foundation of China (Grants no. 21422106, 21673184, 21431005, 21721001, and 21390391) and the Fok Ying Tong Education Foundation (151013). We thank Dr. Wen-Ming Qin and the staffs from the BL17B beamline of National Center for Protein Sciences Shanghai at Shanghai Synchrotron Radiation Facility for assistance during data collection; we also thank Miss Ying-Zi Han for helpful measurement on ESI-MS. We also gratefully acknowledge Mr Xuefu Hu for helpful measurement on time-resolved PL and Miss Rong Chen for her assistance on CV measurement and analysis. 研究工作得到科技部（项目批准号：2014CB845601）、国家自然科学基金委（项目批准号：21422106、21673184、21431005、21721001、21390391）、教育部霍英东基金会青年教师基金（项目批准号：151013）等资助

锡林河流域一个放牧羊草群落中碳素平衡的初步估计

野外调查与历史资料相结合 ,对内蒙古锡林河流域一个放牧羊草 (Leymuschinensis)草原群落的碳素贮量、主要流量和周转速度等进行了估计 ,在此基础上对放牧情况下该群落的碳素收支进行了概算。结果表明 :1)该群落中地上部净初级生产固碳量的两年平均值为 78.2gC·m-2 ·a-1,根系碳素输入量的平均值为 32 2 .5gC·m-2 ·a-1,碳素输入总量为 4 0 0 .7gC·m-2 ·a-1;2 )土壤净呼吸量为 343.7gC·m-2 ·a-1,家畜采食量为 4 9.7gC·m-2 ·a-1,动物(昆虫 )采食量为 14 .7gC·m-2 ·a-1,地上立枯阶段的淋溶与光化学分解损失为 3.2gC·m-2 ·a-1,碳素输出总量为4 11.3gC·m-2 ·a-1;3)该群落中碳素输出略大于输入 ,净释放速率为 10 .6gC·m-2 ·a-1,0～ 30cm土壤中的碳素周转速率为 6 .2 % ,周转时间为 16年

Bias, Biostatistics, and Prognostic Factors

预后因素是患者诊治中非常重要的内容，大多数肿瘤患者的治疗决策取决于各种危险因素的存在与否。最突出的例子就是TNM（即肿瘤，淋巴结，远处转移）分期，但很多疾病都不能简单通过分期一个指标解决所有问题，而是要具体分析每个患者的综合预后因素。目前在判断胸腺瘤预后的临床研究中，一个主要的困难是缺乏实践指南，以至于到底哪些是预后因素尚不明确。本文叙述了临床实践中的一些问题并指出了临床研究中存在的各种偏倚，并试图提供解决方案，其中有许多方面在其它文献中作了详细讨论，但忽视了偏倚的存在。中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)02137-14

The Masaoka-Koga Stage Classification for Thymic Malignancies Clarification and Definition of Terms

目前，胸腺恶性肿瘤尚无国际抗癌联盟（International Union Against Cancer, UICC）和美国癌症联合委员会（American Joint Committeeon Cancer, AJCC）的官方分期。在2017年新版国际肿瘤分期提出较为广泛接受的分期之前，国际胸腺肿瘤协作组织（International Thymic Malignancy Interest Group, ITMIG）仍然建议选用经Koga等修订的Masaoka分期[1-3]。然而， Masaoka和Koga分期都存在一些模糊的术语定义，尤其是对某些细节未作出明确的定义，造成学术界的许多混乱。为此，ITMIG首先由核心工作组起草推荐定义，再交由扩展工作组提炼，并于2010年11月16日ITMIG举办的定义和术语研讨会上进行了进一步修订，最终经ITMIG全体成员讨论后于2011年2月经ITMIG批准并被采用。其灵魂内容是ITMIG对Masaoka-Koga分期系统的许多细节问题给出了较明确定义与解释，旨在使得大家在应用Masaoka-Koga分期的过程中更加一致，以利于相互合作、资源共享，同时便于前瞻性数据的正确收集，最终提出更合理的分期系统供临床使用。本文就此作一综述。中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)0275-8

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies