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Science China Chemistry 2025年第1期68卷 297-307页

作者： Bin Fang Limin Wang Haoqin Li Jiaxin Zhang Yang Ding Pan Pan Li bo Peng Hua Bai Lin Li Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials &Engineering Northwestern Polytechnical University Institute of Flexible Electronics (IFE Future Technologies) Xiamen University

Hepatic ischemia-reperfusion injury（HIRI） is characterized by mitochondrial dysfunction and oxidative stress. Monitoring mitochondrial hydrogen peroxide（mtH2o2） levels in real-time through super-resolution imaging is crucial for elucidating its distribution in live cells and its mechanism of action during HIRI. However, low-background fluorogenic probes have been overlooked in the context of super-resolution imaging. In this study, we developed a low-background fluorogenic probe（MitoWG） with the potential for super-resolution morphology-correlated mitochondrial identification to track the fluctuates of mtH2o2in HIRI. Activation of the desirable fluorescence properties of the probe by mtH2o2was confirmed using structural illumination microscopy（SIM）, enabling high-quality mitochondrial imaging with exceptional specificity and *** in mtH2o2levels were successfully observed in both cellular and rat models of HIRI. Furthermore, we associated the decline in mitochondrial redox homeostasis with accelerated mtH2o2production during HIRI, which triggered mitophagy deficiency and led to cell death. In conclusion, Mito-WG possesses excellent photophysical and low-background properties for SIM imaging, making it a promising tool for mtH2o2tracking in HIRI research and clinical diagnosis.

关键词： hepatic ischemia-reperfusion injury low-background mtH2o2-activatable super-resolution imaging fluorogenic probe

Formation and evolution of supercritical geofluid

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Science China Earth Sciences 2025年第1期68卷 39-51页

作者： Huaiwei NI Yilin XIAo Xiaolin XIoNG Xiandong LIU Chunxiao GAo Yi-Xiang CHEN Yunguo LI Wan-Cai LI Xuan GUo Yang-Yang WANG Dong-bo TAN Li ZHANG State Key Laboratory of Lithospheric and Environmental Coevolution University of Science and Technology of China Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of China Guangzhou Institute of Geochemistry Chinese Academy of Sciences School of Earth Sciences and Engineering Nanjing University State Key Lab of Superhard Materials Jilin University

In this work, we provide a comprehensive review on the formation, evolution, properties, and effects of supercritical geofluid. In Earth's interior, enhanced miscibility between H2o and silicate by the addition of special components or by the increase of pressure and temperature gives rise to supercritical geofluid with a significant amount of both H2o and silicate *** formation of supercritical geofluid in magmatic-hydrothermal systems, typified by pegmatite system, is governed by meltfluid critical curve. The formation of supercritical geofluid in metamorphic systems, typified by subducted slab, is governed by the second critical end point. Experimental results suggest that the presence of boron and fluorine in pegmatite system makes it possible to form supercritical geofluid at crustal depths, but the release of supercritical geofluid from subducted slab is withheld until almost 100 km depth. A major presence of both H2o and depolymerized structural units（monomers, dimers, etc.） endows supercritical geofluid with unique physical properties including low density, low elastic moduli, low viscosity, high diffusivity,and high electrical conductivity. Supercritical geofluid can effectively mobilize a variety of elements even including high field strength elements and heavy rare earth elements. The chemical signatures of supercritical geofluid can be inherited by metasomatized mantle and mantle-derived melts, and this could give an explanation of the oxidation of arc magmas. Phase separation of supercritical geofluid through the mechanism of spinodal decomposition leads to formation of a melt network. Multiphase fluid inclusions recovered from subduction zone rocks and pegmatites are possible relics of supercritical geofluid. Supercritical geofluid can cause electrical anomaly and low seismic velocity near the top of subducted slab, and can be linked with intermediate-focus earthquakes. Supercritical geofluid may have played a crucial role in the formation of pe

关键词： Supercritical geofluid Miscibility Subduction zone Pegmatite

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A versatile synthetic strategy towards rare earth based metal-organic frameworks

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Science China Chemistry 2025年

作者： Quan Shi Yun-Hao Xu Ming-Hui Chen Peng Zhao Wen-bo Deng Ji Xiong Kai Guo Ya-Qing Feng Bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry Jieyang Center

Rare earth metal-organic frameworks (RE-MoFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MoFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3Coo)6·4H2o) as a precursor to construct RE-MoFs.2D RE-MoFs (RE-DBP) and 3D RE-MoFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MoFs were further synthesized to verify the universality of the *** crystalline RE-MoFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MoFs was investigated in the photocatalytic cycloaddition of Co2with *** the RE-DBP(Co) MoFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MoF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MoFs,but also proposes a promising approach for the potential bulk production of RE-MoFs at room temperature.

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Tuning of interactions between cathode and lithium polysulfide in Li-S battery by rational halogenation

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Journal of Energy Chemistry 2020年第10期29卷 147-152页

作者： Samson o.olanrele Zan Lian Chaowei Si Shuo Chen bo Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016LiaoningChina Key Laboratory of Functional Inorganic Material Chemistry(Ministry of Education of China) School of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina Chemical Sciences Department Mountain Top UniversityOgun StateNigeria

Li-S batteries have aroused intense interests as one of the most promising high-energy-density storage ***,the complex undesired shuttle effect induced by dissolution and diffusion of lithium polysulfide intermediates remains the major setback of this *** modification of carbon cathode through heteroatom-doping is widely accepted as an effective method to inhibit the shuttle effect in Li-S battery ***,using first principle calculations,we systematically examined the interaction between halogenated graphene and lithium polysulfide *** is found that the halogen dopants(F,Cl,Br,I)significantly modify the local electronic structure of adsorption site and further induce a polarization to trap the ***,a concave curve is observed from F to I for lithium polysulfide adsorption rather than a linear *** exceptions demonstrated from iodine dopant is carefully analyzed and attributed to its unique charge ***,boron as second dopant further strengthens the interaction between halogenated graphene and polysulfide *** on halogenation strategy,lithium polysulfide/cathode interactions are tuned in a wide range,which can also be of great importance to accelerate redox reaction in Li-S ***,an effective method by halogenation is verified to regulate the adsorption of lithium polysulfide and also enhance the reaction kinetics of the Li-S battery system.

关键词： Li-S battery Halogenation Shuttle effect Co-doping

Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-bo Li Qi Zhang Jun-Zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（o）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and o-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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The first record of ophioleila elegans (Echinodermata:ophiuroidea) from a deep-sea seamount in the Northwest Pacific ocean

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Acta oceanologica Sinica 2018年第10期37卷 180-184页

作者： ZHANG Dongsheng LU bo WANG Chunsheng o'HARA Timothy D Key Laboratory of Marine Ecosystem and Biogeochemistry Second Institute of OceanographyState Oceanic Administration State Key Laboratory of Satellite ocean Environment Dynamics Second Institute of OceanographyState Oceanic Administration Marine Invertebrates Science Museum Victoria

The rare ophiuroid species, ophioleila elegans, was collected by the submersible Jiaolongfrom 1 660 m depth on the Caiwei Guyot located in the Magellan Seamount Chain in the Northwest Pacific ocean. This is the first published record of this species since the types were described from similar habitat off Hawaii. We provide more detailed morphologic characteristics of arm skeleton and a phylogenetic analysis based on Co 1 sequences. both morphology and phylogeny results suggest that the genus ophioleila is more closely related to ophiactids than Hemieuryalids.

关键词： ophioleila elegans systematics deep-sea seamount the Northwest Pacific ocean

(K_(0.5)Na_(0.5))Nb_(1-x)Ta_(x)o_(3)铁电性的第一性原理研究

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原子与分子物理学报 2025年第4期42卷 138-146页

作者：褚新建雷博程刘晨曦刘纪博新疆科技学院信息科学与工程学院库尔勒841000 新疆大学物理科学与技术学院新疆固体物理与器件重点实验室乌鲁木齐830046 西安工业大学光电工程学院西安710032

随着铅基陶瓷的大量使用,造成了严重的环境和健康问题,为了能够找寻替代铅基陶瓷的材料,人们开始了对无铅陶瓷材料的探索.(K_(0.5)Na_(0.5))Nbo_(3)材料由于其优异的铁电压电性能,成为了无铅陶瓷材料的代表,但是碱性组分在高温下的高挥... 详细信息

随着铅基陶瓷的大量使用,造成了严重的环境和健康问题,为了能够找寻替代铅基陶瓷的材料,人们开始了对无铅陶瓷材料的探索.(K_(0.5)Na_(0.5))Nbo_(3)材料由于其优异的铁电压电性能,成为了无铅陶瓷材料的代表,但是碱性组分在高温下的高挥发性使其应用范围受到了极大的限制.基于这样的考虑,本文基于密度泛函理论的第一性原理方法,探究了(K_(0.5)Na_(0.5))Nb_(1-x)Taxo_(3)(x=0.125,0.25,0.375,0.5,0.625,0.75,0.875,1)九种体系的铁电性能,结果表明:随着Ta浓度的增加,晶格常数发生了突变,由此猜测KNN材料随着Ta浓度的增加,发生了正交-单斜的相变;Ta的掺入能够降低KNN材料的烧结难度,且随着Ta浓度的增加,形成难度逐渐降低;掺杂体系中,Ta-4f轨道与Na-3p,K-4p以及o-2s轨道电子发生了杂化,使导带底Nb-4d与Na-3p电子的态密度峰向高能区移动,禁带宽度呈现增加的趋势;在分析KNN材料铁电性作用机理时发现KNN的铁电极化类型是离子位移型极化,且在[001]方向上不具有极化能力.分析掺杂后各个体系的极化强度,发现随着Ta浓度的增加,极化强度逐渐降低,但是在低浓度掺杂时极化有向上增加的趋势,这可能是体系在低浓存在着正交与单斜的准同型相界(Morphotropic phase boundary,MPB)导致的,由此可以判断,低浓度掺杂有利于提高KNN材料的铁电性能.

关键词：第一性原理钙钛矿结果 KNN 铁电性

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boosting electrocatalytic activity for Co_(2) reduction on nitrogen-doped carbon catalysts by co-doping with phosphorus

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Journal of Energy Chemistry 2021年第3期30卷 143-150页

作者： Shuo Chen Tianfu Liu Samson o.olanrele Zan Lian Chaowei Si Zhimin Chen bo Li Key Laboratory of Functional Inorganic Material Chemistry(Ministry of Education of China) School of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina

Electrochemical reduction of Co_(2)(CERR)to value-added chemicals is an attractive strategy for greenhouse gas mitigation,and carbon recycles *** metal catalysts suffered from low durability and sluggish kinetics impede the practical *** the other hand,doped carbon materials recently demonstrate superior catalytic performance in CERR,which shows the potential to diminish the problems of metal catalysts to some ***,we present the design and fabrication of nitrogen(N),phosphorus(P)co-doped metal-free carbon materials as an efficient and stable electrocatalyst for reduction of Co_(2) to Co,which exhibits an excellent performance with a high faradaic efficiency of 92%(-0.55 V ***)and up to 24 h stability.A series of characterizations including TEM and XPS verified that nitrogen and phosphorous are successfully incorporated into the carbon ***,the comparisons between co-doping and single doping catalysts reveal that co-doping can significantly increase CERR *** improved catalytic activity is attributed to the synergetic effects between nitrogen and phosphorous dopants,which effectively modulate properties of the active *** density functional theory(DFT)calculations were also performed to understand the synergy effects of *** is revealed that the phosphorous doping can significantly lower the Gibbs free energy of CooH^(*)***,the introduction of the second dopants phosphorous can reduce the reaction barrier along the reaction path and cause polarization of density of states at the Fermi *** changes can greatly enhance the activity of the *** a combined experimental and computational exploration,current work provides valuable insights into the reaction mechanism of CERR on N,P co-doped carbon catalysts,and the influence from synergy effects between dopants,which paves the way for the rational design of novel metal-free catalysts for Co2 electro-reduction.

关键词： Metal-free catalyst Co_(2)reduction Co-doping,DFT

Expression of cyclooxygenase-2 is associated with p53 accumulation in premalignant and malignant gallbladder lesions

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World Journal of Gastroenterology 2006年第21期12卷 3425-3429页

作者： Mateja Legan bo(s|ˇ)tjan Luzar Vera Ferlan Marolt Andrej C(o|¨)r Institute for Histology and Embryology Medical Faculty University of Ljubljana Korytkova 21000 LjubljanaSlovenia Institute of Pathology Medical Faculty University of Ljubljana Korytkova 21000 LjubljanaSlovenia

AIM： To examine the relationship between cyclooxygenase-2 （CoX-2） overexpression and p53 accumulation in gallbladder carcinoma and its precursor ***： Sixty-eight gallbladder tissue samples comprising 14 cases of normal gallblader epithelium, 27 cases of dysplasia （11 low-grade dyplasia and 16 high-grade dysplasia） and 27 adenocarcinomas were evaluated by immunohistochemistry for CoX-2 expression and p53 accumulation. The relationship among CoX-2 expression, p53 accumulation and clinicopathological characteristics was ***： CoX-2 was expressed in 14.3% of normal gallbladder epithelium, 70.3% of dysplastic epite hlium, and 59.2% of adenocarcinomas. When divided into low- and high-grade dysplasia, CoX-2 was positive in 5 （45.4%） cases of low-grade and 2d （87.5%） of high- grade dysplasia （P = 0.019）. Accumulation of p53 was detected in 5 （32.2%） cases of high-grade dysplasia and in 23 （48.2%） of carcinomas. No p53 accumulation was found in normal epithelium or low-grade dysplasia. CoX-2 overexpression was observed in 27 of 28 （94.4%） cases with p53-accumulation in comparison with 20 （40.0%） out of 50 cases without p53 accumulation （P 〈 0.001）.CoNCLUSIoN： The significant differences in CoX-2 expression among normal epithelium, low-grade dysplasia and high-grade dysplasia suggest that overexpression of CoX-2 enzyme is an early event in gallbladder carcinogenensis. Furthermore, since accumulation of p53 correlates with CoX-2 expression, CoX-2 overexpression observed in gallbladder high-grade dysplasia and carcinoma might be partly due to the dysfunction of p53.

关键词： Gallbladder Carcinogenesis Cyclooxygenase-2 p53 Immunohystochemistry

First spaceborne demonstration of BeiDou-3 signals for GNSS reflectometry from CYGNSS constellation

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Chinese Journal of Aeronautics 2021年第9期34卷 1-10页

作者： Weiqiang LI Estel CARDELLACH Serni RIbo Antonio RIUS bo ZHoU Institute of Space Sciences(ICE CSIC)Barcelona 08193Spain Institut d'Estudis Espacials de Catalunya(IEEC) Barcelona 08034Spain Shanghai Spaceflight Institute of TT&C and Telecommunications Shanghai 201109China

The full constellation of Chinese Global Navigation Satellite System(GNSS)Bei Dou-3 has been deployed completely and started fully operational *** addition to providing global Positioning,Navigation and Timing(PNT)services,the Bei Dou-3 satellites transmissions can also be used as the sources of illumination for Earth observation(Eo)with a bistatic radar *** innovative Eo concept,known as GNSS reflectometry(GNSS-R),allows to measure the Earth surface characteristics at high resolution via the reflected L-band radar signals collected by a constellation of small,low cost and low Earth orbiting *** the first time in orbit,earth reflected Bei Dou-3 signal has been detected from the limited sets of raw data collected by the NASA’s Cyclone GNSS(CYGNSS)*** feasibility of spaceborne Bei Dou-3 reflections on two typical applications,including sea surface wind and flooding inundation detection,has been *** methodology and results give new strength to the prospect of new spaceborne GNSS-R instruments and missions,which can make multi-GNSS reflectometry observations available to better capture rapidly changing weather systems at better spatio-temporal scales.

关键词： Global Navigation Satellite System(GNSS) BeiDou-3 Small satellites Bistatic radar GNSS Reflectometry(GNSS-R) CYGNSS Tropical cyclone Flood inundation