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Synthesis and Structure Characterization of a tetranuclear Manganese(Ⅲ) Complex:[Mn_4O_2(O_2CMe)_6(MeOh)_2(dbm)_2]·2MeCOOh·2Ch_2Cl_2

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Chinese Journal of Structural Chemistry 2007年第3期26卷 295-298页

作者： WANG Mei MA Cheng-Bing WANG hui-Sheng ChEN chang-Neng LIU Qiu-tian State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

the title compound, [Mn4O2（O2CMe）6（MeOh）2（dbm）2]·2MeCOOh·2Ch2Cl2 （hdbm = dibenzoylmethane）, has been synthesized and structurally determined by single-crystal X-ray diffraction. the crystal belongs to triclinic, space group P/, with a = 10.729（3）, b = 12.269（3）, c = 13.085（4） A, a = 106.367（3）,β = 107.643（2）, γ = 94.771（2）°, V = 1547.9（7） A^3, Z = 1, C50h64Cl4Mn4O24, Mr= 1410.57, Dc= 1.513 g/cm^3, F（000） = 724, Rint = 0.0147, t= 293（2） K and p = 1.046 mm ^-1. the final R = 0.0359 and wR = 0.0938 for 5791 observed reflections with 1 〉 2σ（/）. the structure of the complex consists of one [Mn4（μ3-O）2]^8＋ core with four coplanar Mn atoms disposed in an extended ＂butterfly-like＂ arrangement and two O atoms triply bridging each ＂wing＂, and the peripheral ligation is provided by six by-MeCO2^-, two terminal ,μ2-dbm- groups at the two ends of the molecule, and two MeOh molecules on the central Mn atoms, lntermolecular O…h-O hydrogen bonding interactions are found within the structure of the compound.

关键词： manganese crystal structure photosystem Ⅱ hydrogen bonding

miR-211 regulates the antioxidant function of lens epithelial cells affected by age-related cataracts

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International Journal of Ophthalmology(English edition) 2018年第3期11卷 349-353页

作者： Bo Lu Ian t. Christensen Li-Wei Ma tao Yu Ling-Feng Jiang Chun-Xia Wang Li Feng Jin-Song Zhang Qi-chang Yan Xin-Ling Wang Department of Ophthalmology the Fourth Affiliated Hospital of China Medical University Key Laboratory of Lens Research of Liaoning Province Eye Hospital of China Medical University Shenyang 110005 Liaoning Province China University of Utah School of Medicine Salt Lake City Utah 84132 USA Department of Medical Imaging Cancer Hospital of China Medical University Liaoning Cancer Hospital & Institute Shenyang 110042 Liaoning Province China

AIM： to investigate the effects and mechanism of miR-211 in mediating the antioxidant function of lens epithelial cells affected by age-related cataracts. MEthODS： Real-time quantitative polymerase chain reaction （Rt-qPCR） was used to detect miR-211 expression in the anterior lens capsules of healthy people, the anterior lens capsules of patients with age-related cataracts, and human epithelial cell line （SRA01/04） cells exposed to oxidative stress. A 2＇, 7＇-dichloro-fluorescein diacetate （DCFh-DA） probe was used to measure the levels of endogenous reactive oxygen species （ROS） in human lens epithelial cells （hLECs） exposed to 400 pmol/L h2O2 for lh. SRA01/04 cells were transfected with either miR-211 mimics, mimic controls, miR-211 inhibitors or inhibitor controls. After 72h, these cells were exposed to 400 IJmollL h2O2 for lh, then p53 and Bax mRNA expression were measured using Rt-qPCR. p53 and Bax protein expression were also measured by Western blotting analysis. Finally, cell viability was assessed using an MtS assay. RESULtS： Compared to the control group, expression of miR-211 in the anterior lens capsules of age-related cataract patients and in SRA01/04 cells exposed to oxidative stress was significantly increased （P〈0.001）. Levels of endogenous ROS were significantly elevated in hLECs exposed to oxidative stress （P〈0.001）. Compared to the mimic control group, the hLECs in the miR-211 mimic group expressed significantly higher levels of p53 and Bax mRNA and protein while cell viability was significantly reduced （P〈0.001）. Conversely, p53 and Bax mRNA and protein expression were significantly reduced in the miR-211 inhibitor group as compared to the control group, while the cells in this group had much higher levels of call viability （P〈0.001）. CONCLUSION： miR-211 is upregulatsd in the anterior lens capsules of age-related cataract patients, miR-211 decreased the antioxidative stress capacity of lens epithelial cells by upregulating p53 and Bax, while inhib

关键词： KEYWORDS: miR-211 p53 Bax age-related cataract oxi-dative stress

theoretical Studies on Reaction Mechanisms of hNCS with Nh(X^3Σ)

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Chemical Research in Chinese Universities 2006年第5期22卷 635-638页

作者： LIU Peng-jun ZhANG Lian-hua SUN hao chang Ying-fei WANG Rong-shun Chemistry Depatrment of hainan Normal University Haikou 571158 P. R. China Institute of Functional Material Chemistry Faculty of ChemistryNortheast Normal University Changchun 130024 P. R. China

the reaction mechanisms of hNCS with Nh（X^3∑ ） were theoretically investigated. the minimum energy paths （MEP） of the reaction were calculated by using the density functional theory（DFt） at the B3LYP/6-311 ＋＋ G^＊＊ level. the equilibrium structural parameters, the harmonic vibrational frequencies, the total energies, and the zeropoint energies（ZPE） of all the species were calculated. the single-point energies along the MEP were further refined at the QCISD（t）/6-311 ＋＋ G^＊＊ level. It was found that the mechanisms of the hNCS ＋ Nh（X^3∑） reaction involve two channels producing the hNC ＋ hNS and the N2h2 ＋ CS products. Channel 1 plays a dominant role and the hNC ＋ hNS are the main preduets. the reaction is exothermie.

关键词： hNCS Nh(X^3∑) Reaction mechanism Density functional theory(DFt)

rac-11-t-Butoxy-1,4-dihydro-1,4-methanoanthracene:A two-dimensional framework structure built from C-h…O and C-h…π hydrogen bonds

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Chinese Chemical Letters 2012年第9期23卷 1043-1046页

作者： hsing Yang tsai Ming Jen chang tzu Chien Fang Kew Yu Chen Department of Chemical Engineering Feng Chia University40724 TaichungTaiwan

the title compound rac-11-t-butoxy-l,4-dihydro-l,4-methanoanthracene （C19h200, Mr = 264.35） has been synthesized and characterized by Ft-IR, 1h NMR, hRMS spectra and single-crystal X-ray diffraction. the crystal belongs to monoclinic, space group P21/n, with a = 13.5240（10）, b = 8.3453（6）, c = 13.9604（9） A,β = 100.0190（10）°. the structure of the title compound comprises a norbornene unit with a t-butoxy g, roup, having a naphthalene ring fused on one side. the naphthalene is essentially planar with a maximum deviation of 0.032（2） A for atom C（3）. In the crystal, inversion-related molecules are linked by pairs of C- h...O hydrogen bonds, forming a cyclic dimer with R2z （16） graph-set motif. the C-h-..~r interactions are also observed, linking the molecules into a continuous two-dimensional framework structure.

关键词： X-ray diffraction Norbomene derivatives Crystal structure Puckering parameters

Investigation of MXenes as oxygen reduction electrocatalyst for selective h_(2)O_(2) generation

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Nano Research 2022年第5期15卷 3927-3932页

作者： Xiao huang Min Song Jian Zhang Jingjing Zhang Wei Liu chang Zhang Wang Zhang Deli Wang Key Laboratory of Material Chemistry for Energy Conversion and Storage(huazhong University of Science and technology) Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518055China

two-electron oxygen reduction reaction(ORR)catalysts are essential for the electrosynthesis of hydrogen peroxide(h_(2)O_(2)).MXenes,a rising family of two-dimensional(2D)transition metal carbides,have been extensively studied for energy storage and(photo)electrocatalysis due to their rich chemical compositions and tunable electronic *** this work,three representative MXenes of ti_(3)C_(2)t_(x),V_(2)CtX,and Nb_(2)CtX were selected for h_(2)O_(2)electrosynthesis and we found that MXenes are inherent two-electron ORR catalysts with high h_(2)O_(2)*** addition,this work critically evaluates their electrocatalytic activity and ***,Nb_(2)Ct_(x)catalyst maintains better electrocatalytic activity and higher stability for a long time test,although the stability of ti_(3)C_(2)t_(x)and V_(2)Ct_(x)catalysts is poor owing to the metal dissolution property of ti and V in alkaline ***,the assembled device based on Nb2Ctx catalyst presents a high h2O2 production and a rapid organic dye decoloration ability.

关键词： electrosynthesis hydrogen peroxide oxygen reduction reaction MXenes

Bandgap opening in Mote2 thin flakes induced by surface oxidation

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Frontiers of physics 2020年第3期15卷 105-111页

作者： Yuan Gan Jiyuan Liang chang-woo Cho Si Li Yanping Guo Xiaoming Ma Xuefeng Wu Jinsheng Wen Xu Du Mingquan he chang Liu Shengyuan A.Yang Kedong Wang Liyuan Zhang National Laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing210093China Department of Physics Southern University of Science and TechnologyShenzhen518055China School of Physics and Electronics Hunan Normal UniversityChangsha410081China Research Laboratory for Quantum Materials Singapore University of Technology and DesignSingapore487372Singapore Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing100190China Department of Physics and Astronomy Stony Brook UniversityStony BrookNY11794USA Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials College of PhysicsChongqing UniversityChongqing401331China

Recently,the layered transition metal dichalcogenide 1t′-Mote2 has generated considerable interest due to their superconducting and non-trivial topological ***,we present a systematic study on 1t′-Mote2 single-crystal and exfoliated thin-flakes by means of electrical transport,scanning tunnelling microscope(StM)measurements and band structure *** a bulk sample,it exhibits large magneto-resistance(MR)and Shubnikov–de hass oscillations inρxx and a series of hall plateaus inρxy at low ***,the Mote2 thin films were intensively investigated with thickness *** samples,without encapsulation,an apparent transition from the intrinsic metallic to insulating state is observed by reducing *** such thin films,we also observed a suppression of the MR and weak anti-localization(WAL)*** attributed these effects to disorders originated from the extrinsic surface chemical reaction,which is consistent with the density functional theory(DFt)calculations and in-situ StM *** contrast to samples without encapsulated protection,we discovered an interesting superconducting transition for those samples with hexagonal Boron Nitride(h-BN)film *** results indicate that the metallic or superconducting behavior is its intrinsic state,and the insulating behavior is likely caused by surface oxidation in few layer 1t’-Mote2 flakes.

关键词： two-dimensional materials metal-insulator transition layered transition metal dichalcogenides(tMDs) surface oxidation

In situ formed LiF-Li_(3)N interface layer enables ultra-stable sulfide electrolyte-based all-solid-state lithium batteries

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Journal of Energy Chemistry 2023年第4期79卷 272-278页

作者： Ming Wu Mengqi Li Yuming Jin Xinshuang chang Xiaolei Zhao Zhi Gu Gaozhan Liu Xiayin Yao School of Material Science and Chemical Engineering Ningbo UniversityNingbo 315211ZhejiangChina Ningbo Institute of Materials technology and Engineering Chinese Academy of SciencesNingbo 315201ZhejiangChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Sulfide solid electrolytes are promising for high energy density and safety in all-solid-state batteries due to their high ionic conductivity and good mechanical ***,the application of sulfide solid electrolytes in all-solid-state batteries with lithium anode is restricted by the side reactions at lithium/electrolytes interfaces and the growth of lithium dendrite caused by nonuniform lithium ***,a homogeneous LiF-Li_(3)N composite protective layer is in situ formed via a manipulated reaction of pentafluorobenzamide with Li *** LiF-Li_(3)N layer with both high interfacial energy and interfacial adhesion energy can synergistically suppress side reactions and inhibit the growth of lithium dendrite,achieving uniform deposition of *** critical current densities of Li_(10)GeP_(2)S_(12)and Li_(6)PS_(5)Cl are increased to 3.25 and 1.25 mA cm^(-2)with Li@LiF-Li_(3)N layer,which are almost triple and twice as those of Li-symmetric cells in the absence of protection layer,***,the Li@LiF-Li_(3)N/Li10GeP2S12/Li@LiF-Li_(3)N cell can stably cycle for 9000 h at 0.1 mA cm^(-2)under 0.1 mA h cm^(-2),and Li@LiF-Li_(3)N/Li_(6)PS_(5)Cl/Li@LiF-Li_(3)N cell achieves stable Li plating/stripping for 8000 h at 0.1 mA cm^(-2)under10 m A h cm^(-2).the improved dynamic stability of lithium plating/stripping in Li@LiF-Li_(3)N/Li_(10)GeP_(2)S_(12)or Li_(6)PS_(5)Cl interfaces is proved by three-electrode *** a result,LiCoO_(2)/electrolytes/Li@LiF-Li_(3)N batteries with Li_(10)GeP_(2)S_(12)and Li_(6)PS_(5)Cl exhibit remarkable cycling stability of 500 cycles with capacity retentions of 93.5%and 89.2%at 1 C,respectively.

关键词： LiF-Li_(3)N Sulfide solid electrolytes Interface modification high interface energy All-solid-state batteries

Facile synthesis of zinc-based organic framework for aqueous hg (Ⅱ) removal: Adsorption performance and mechanism

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Nano Materials Science 2021年第4期3卷 429-439页

作者： Biao Zeng Wei Wang Sijin he Guo Lin Wenjia Du Jun chang Zhao Ding the State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081PR China Key Laboratory for Ferrous Mtallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081PR China China E-port Data Center Division of Chengdu Chengdu610041PR China Electrochemical Innovation Lab Department of Chemical EngineeringUniversity College London(UCL)LondonWC1E 68TUK College of Material and Chemical Engineering tongren University Tongren554300GuizhouPR China Department of Mechanical Materials and Aerospace Engineering Illinois Institute of TechnologyChicagoIL60616 USA

Mercury(hg)ions can lead to a serious impact on the environment;therefore,it was necessary to find an effective method for absorbing these toxic hg ***,the adsorbent(Zn-AhMt)was synthesized from zinc nitrate and 4-amino 3-hydrazine-5 mercapto-1,2,4-triazole(AhMt)by one-step method and,characterized the microstruc-ture and absorption performance by fourier transform infrared spectroscopy(FtIR),field emission scanning electron microscopy(FESEM),X-ray diffraction(XRD),Brunauer-Emmett teller(BEt),thermal Gravimetric Analyzer(tGA)and X-ray photoelectron spectroscopy(XPS).through a plethora of measurements,we found that the maximum adsorption capacity was 802.8 mg/g when the optimal ph of Zn-AhMt was *** isothermal and kinetic experiments confirm that the reaction process of Zn-AhMt was chemisorption,while the adsorption process conforms to the hill model and pseudo second order kinetic *** experiments showed that the adsorption process was spontaneous and *** experiments were performed in the simulated wastewater containing Mn,Mg,Cr,Al,Co,Ni,hg *** results showed that the Zn-AhMt has a stronger affinity for hg *** removal rate of Zn-AhMt remained above 98%,indicating that the Zn-AhMt had a good stability validated by three adsorption-desorption repeatable *** to the XPS results,the adsorption reaction of Zn-AhMt was mainly attributed to the chelation and ion *** was further explained by both density functional theory(DFt)calculation and frontier molecular orbital *** therefore propose the adsorption mechanism of *** adsorption reaction facilitates via the synergistic action of S and N ***,the bonding between the adsorbent and the N atom has been proved to be more *** study demonstrated that Zn-AhMt had a promising application prospect in mercury removal.

关键词： Metal-organic frameworks(MOFs) hg(Ⅱ) Selectivity Adsorption mechanism

Vertically aligned reduced graphene oxide/ti_(3)C_(2)t_(x)MXene hybrid hydrogel for highly efficient solar steam generation

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Nano Research 2020年第11期13卷 3048-3056页

作者： Wei Li Xiaofeng Li Wei chang Jing Wu Pengfei Liu Jianjun Wang Xi Yao Zhong-Zhen Yu State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029China Institute of Chemistry Chinese Academy of SciencesBeijing100190China Department of Biomedical Sciences City University of Hong KongHong Kong999077China Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing100029China

Effective utilization of abundant solar energy for desalination of seawater and purification of wastewater is one of sustainable techniques for production of clean water,helping relieve global water resource ***,we fabricate a vertically aligned reduced graphene oxide/ti_(3)C_(2)t_(x)MXene(A-RGO/MX)hybrid hydrogel with aligned channels as an independent solar steam generation device for highly efficient solar steam *** vertically aligned channels,generated by a liquid nitrogen-assisted directional-freezing process,not only rapidly transport water upward to the evaporation surface for efficient solar steam generation,but also facilitate multiple reflections of solar light inside the channels for efficient solar light *** deliberate slight reduction endows the RGO with plenty of polar groups,decreasing the water vaporization enthalpy effectively and hence accelerating water evaporation *** MXene sheets,infiltrated inside the A-RGO hydrogel on the basis of Marangoni effect,enhance light absorption capacity and photothermal conversion *** a result,the A-RGO/MX hybrid hydrogel achieves a water evaporation rate of 2.09 kg·m^(−2)·h^(−1)with a high conversion efficiency of 93.5%under 1-sun ***,this photothermal conversion hydrogel rapidly desalinates seawater and purifies wastewater to generate clean water with outstanding ion rejection rates of above 99%for most ions.

关键词： anisotropic hydrogel MXene reduced graphene oxide solar steam generation aligned channels