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Comparison of Si_n^+ and Ge_n^+(n=2―15) Cationic Structures

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Chemical Research in Chinese Universities 2011年第2期27卷 313-317页

作者： QIN Wei ZANG Qing-jun LU Wen-cai WANG Cai-zhuang ho kai-ming Laboratory of Fiber Materials and Modern Textile Growing Base for State Key Laboratory College of Physics Qingdao University Qingdao 266071 P. R. China State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130021 P. R. China College of Chemistry Beijing Normal University Beijing 100875 P. R. China Ames Laboratory-US DOE and Department of Physics and Astronomy Iowa State University Ames IA 50011 USA

We designed and optimized a large number of the isomers of Si12＋ at the level of density functional theory （DFT）-B3LYP/6-311＋＋G（d） using the Gaussian 03 software package. An unambiguous structure of the Si12＋ cluster is presented, whose IR spectrum agrees well with the experiment result. The most stable geometric structures of Gen＋（n=2―15） clusters were determined by the all-electron PBE/DND method in DMol3 of the Material Studio Package, and compared with those of the corresponding Sin＋ geometries. Most structures of Gen＋ and Sin＋ are similar except the ones of those for n=9, 12, 13 and 14, and the pentagonal bipyramid motif and the tri-capped trigonal prism（TTP） motif often appear in the Sin＋ and Gen＋（n=7―15） structures（except for Si14＋）.

关键词： Pentagonal bipyrarnid motif Tri-capped trigonal prism(TTP) motif Si.+ and Ge.+ cluster

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地核物质成分、结构与形核研究进展

矿物岩石地球化学通报 2024年

作者：高宸 kai-ming ho 孙阳厦门大学物理科学与技术学院爱荷华州立大学物理与天文系

地核由液态外核和固态内核组成，其主要化学成分是铁，此外还包含少量镍和轻质元素，这些元素在内、外核中的含量存在较大争议。地震波数据显示，内地核具有显著的各向异性，可能与其晶体结构和物态密切相关，但研究者们对此尚未完全理... 详细信息

地核由液态外核和固态内核组成，其主要化学成分是铁，此外还包含少量镍和轻质元素，这些元素在内、外核中的含量存在较大争议。地震波数据显示，内地核具有显著的各向异性，可能与其晶体结构和物态密切相关，但研究者们对此尚未完全理解。同时，内核的年龄及结晶过程也存在许多谜团。地核成分、结构及其形成过程对于理解地球深部演变至关重要。近年来，随着高压实验和第一性原理计算模拟的发展，各种物理和化学手段被广泛应用于研究地核物质物性问题。本文总结了近十年来地核物质成分、结构及结晶过程的研究进展，概述了镍与轻元素在内、外核中的含量及其对地核结构、密度和地震波速等性质影响的研究结果，指出了探究地核多元物质固液相图的重要性。此外，本文还简要总结了与内核年龄相关的研究工作，阐释了在探究地核演化过程中发现的理论难题与悖论。本文可为未来的地核研究提供一定的参考。

关键词：地球地核地核组分内地核结构内地核形核

Enhancing photodynamic inactivation via tunning spatial constraint on photosensitizer

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Science China Chemistry 2024年第2期67卷 652-663页

作者： Chong Li minghao Han Ji Gao Shuxian Wang Song-Bo Lu Yaxi Li Zhao Liu Chen Zhang Zhaojin Wang Fangliang Wang Yuang Sun Chun Loong ho kai Wang Yun Shen kai Li Shenzhen Key Laboratory of Smart Healthcare Engineering Guangdong Provincial Key Laboratory of Advanced BiomaterialsDepartment of Biomedical EngineeringSouthern University of Science and TechnologyShenzhen518055China Department of Chemical and Environmental Engineering University of California RiversideRiverside92521USA Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen518055China

The critical factor of spatial constraint,provided by the external confinement(e.g.,matrix),is often overlooked during photodynamic inactivation,despite playing a crucial role in determining the molecular photophysical process and subsequent antipathogen ***,as a proof-of-concept model,we employed two types of polymers with varying interaction energies with dopants to investigate the intrinsic relationship between spatial constraint and the essential excited-state behaviors of doped photosensitizer(4-(2-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)ethyl)-1-methylquinolin-1-ium iodine,TPP).Through experimental investigation and theoretical calculations,we found that TPP tends to remain in the excited state for a shorter dwell time under weaker spatial constraints due to less restricted molecular motion in polyurethane(PU) ***,the singlet oxygen(^(1)O_(2)) generated from doped-TPP shows a 9.23-fold enhancement in PU than in the polyvinylchloride(PVC) *** light irradiation,the PU@TPP nanofiber can efficiently eliminate the coronavirus MHV-A59(≥99.9997%) at a 220,000-fold higher concentration than the infected *** antibacterial efficacy has also been demonstrated,with a killing rate of ≥99%.

关键词： photodynamic antibacterial singlet oxygen triphenylamine nanofiber

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Si纳米晶阵列的光学性质理论研究

Si纳米晶阵列的光学性质理论研究

Genomics-driven derivatization of the bioactive fungal sesterterpenoid variecolin:Creation of an unnatural analogue with improved anticancer properties

上海市激光学会2013年学术年会

作者：王子仪张荣君王松有陈良尧 Wang Cai-Zhuang ho kai-ming 复旦大学信息科学与工程学院光科学与工程系 Ames Laboratory Department of Physics and AstronomyIowa State University

利用离散偶极子近似法和基于平面波的传输矩阵法研究了Si纳米晶阵列的光学性质。发现Si纳米晶具有极强的消光效应,并利用米氏模型对这种消光效应进行了解释。对其在光伏电池、探测器等器件上的应用提供了理论依据。

关键词：纳米晶消光米氏振荡

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Acta Pharmaceutica Sinica B 2024年第1期14卷 421-432页

作者： Dexiu Yan Jemma Arakelyan Teng Wan Ritvik Raina Tsz Ki Chan Dohyun Ahn Vladimir Kushnarev Tsz Kiu Cheung ho Ching Chan Inseo Choi Pui Yi ho Feijun Hu Yujeong Kim Hill Lam Lau Ying Lo Law Chi Seng Leung Chun Yin Tong kai Kap Wong Wing Lam Yim Nikolay S.Karnaukhov Richard Y.C.Kong Maria V.Babak Yudai Matsuda Department of Chemistry City University of Hong KongHong Kong SARChina iGEM Team“VarieCure” City University of Hong KongHong Kong SARChina Department of Biomedical Engineering City University of Hong KongHong Kong SARChina Moscow Clinical Research Center Named After A.S.Loginov Moscow 111123Russian Federation

A biosynthetic gene cluster for the bioactive fungal sesterterpenoids variecolin(1)and variecolactone(2)was identified in Aspergillus aculeatus ATCC *** production of 1 and 2 was achieved in Aspergillus oryzae by expressing the sesterterpene synthase VrcA and the cytochrome P450 ***,the replacement of VrcB with homologous P450s from other fungal terpenoid pathways yielded three new variecolin analogues(5-7).Analysis of the compounds’anticancer activity in vitro and in vivo revealed that although 5 and 1 had comparable activities,5 was associated with significantly reduced toxic side effects in cancer-bearing mice,indicating its potentially broader therapeutic *** study describes the first tests of variecolin and its analogues in animals and demonstrates the utility of synthetic biology for creating molecules with improved biological activities.

关键词： Animal studies Anticancer properties Biosynthesis Natural products Sesterterpenoids Synthetic biology Terpene synthases Variecolin

Antioxidant effects of the aqueous extract of turmeric against hydrogen peroxide-induced oxidative stress in spotted seabass(Lateolabrax maculatus)

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Aquaculture and Fisheries 2024年第1期9卷 71-77页

作者： Zhe Wang Xiuqin Wang Xueshan Li Kangle Lu Ling Wang Xuekun Ma kai Song Chunxiao Zhang Xiamen Key Laboratory for Feed Quality Testing and Safety Evaluation Fisheries College of Jimei UniversityXiamen361021China Guangdong Yuehai Feed Group Co. Ltd.GuangdongZhanjiang524000China

Intensive aquaculture-induced oxidative stress is detrimental to fish health and *** plants show promise as natural health boosters and antioxidants in the aquaculture ***,this work investigated the effects of turmeric aqueous extract(TAE)on the growth performance,antioxidant status,and hydrogen peroxide(H2O2)-induced oxidative stress in spotted seabass(Lateolabrax maculatus).Fish were fed diets supplemented with 0(Con),2(TAE2),or 4(TAE4)g/kg TAE for eight weeks,then were injected with *** results showed that dietary supplementation of TAE did not affect fish growth,feed utilization,or body *** treatment increased liver antioxidant enzyme activities and decreased liver malondialdehyde content and serum levels of glutamate oxalate transaminase,glutamate pyruvate transaminase,and lactate ***,the increases in mortality,liver malondialdehyde content,and serum biomarkers of liver injury in the H2O2-treated fish were inhibited as a consequence of the TAE *** addition,TAE treatment activated the Nrf2/Keap1 pathway in the liver,supported by the up-regulated expression of nrf2,ho-1,and gclc,and down-regulated keap1 ***,dietary incorporation of TAE protected against H2O2-induced oxidative stress in spotted seabass probably by enhancing antioxidant capacity through the Nrf2/Keap1 pathway.

关键词： Turmeric Medicinal plant Hydrogen peroxide Oxidative stress Lateolabrax maculatus

Prediction of Van hove singularity systems in ternary borides

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npj Computational Materials 2023年第1期9卷 247-257页

作者： Yang Sun Zhen Zhang Andrew P.Porter Kirill Kovnir kai-ming ho Vladimir Antropov Department of Physics Xiamen University361005 XiamenChina Department of Physics and Astronomy Iowa State UniversityAmesIA 50011USA Department of Chemistry Iowa State UniversityAmesIA 50011USA Ames National Laboratory U.S.Department of EnergyAmesIA 50011USA

A computational search for stable structures among bothαandβphases of ternary ATB4 borides(A=Mg,Ca,Sr,Ba,Al,Ga,and Zn,T is 3d or 4d transition elements)has been *** found thatα-ATB4 compounds with A=Mg,Ca,Al,and T=V,Cr,Mn,Fe,Ni,and Co form a family of structurally stable or almost stable *** systems are metallic in non-magnetic states and characterized by the formation of the localized molecular-like state of 3d transition metal atom dimers,which leads to the appearance of numerous Van hove singularities in the electronic *** closeness of such singularities to the Fermi level can be easily tuned by electron *** the atoms in the middle of the 3d row(Cr,Mn,and Fe),these singularities led to magnetic instabilities and magnetic ground states with a weakly metallic or semiconducting *** states appear as non-trivial coexistence of the different spin ladders formed by magnetic dimers of 3d *** magnetic states can be characterized as an analog of the spin glass *** attempts to produce MgFeB4 and associated challenges are discussed,and promising directions for further synthetic studies are formulated.

关键词： metallic ternary magnetic

Temperature-induced Sn(Ⅱ) supramolecular isomeric frameworks as promising heterogeneous catalysts for cyanosilylation of aldehydes

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Science China Chemistry 2020年第2期63卷 182-186页

作者： kai Sheng Li-ming Fan Xue-Fei Tian Rakesh Kumar Gupta Linna Gao Chen-ho Tung Di Sun Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringState Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China School of Aeronautics Shandong Jiaotong UniversityJinan 250037China Department of Chemistry College of ScienceNorth University of ChinaTaiyuan 030051China College of Chemical and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China

Two novel Sn(Ⅱ) supramolecular isomeric frameworks,with the identical formula of {(NH2Me2)2[Sn(BDC)(SO4)]}n,Sn-CP-1-α(1) and Sn-CP-1-β(2)(H2BDC=terephthalic acid) were synthesized under solvothermal condition and fully characterized by single crystal X-ray diffraction(SCXRD),Fourier transform infrared spectroscopy(FTIR),ultraviolet-visible spectroscopy(UVVis),elemental analyses,and thermogravimetric analysis(TGA).Interestingly,the structures of 1 and 2 are governed by the temperature of the reaction,suggesting a temperature-induced supramolecular *** supramolecular isomers are primarily caused by the different bridging alignments of SO42–.Compounds 1 and 2 display 2 D layer and 3 D framework with different topologies,non-interpenetrated 44-sql and two-fold interpenetrated 4-connected dia topology,*** to Lewis acid properties of coordinatively unsaturated Sn(Ⅱ) sites in CPs,they have been utilized as heterogeneous catalyst for the cyanosilylation of aldehydes with an excellent conversion yield over 99% under solvent-free conditions.

关键词： supramolecular isomerism Sn(Ⅱ)coordination polymers catalysis cyanosilylation

Hydrogen-rich water alleviates constipation by attenuating oxidative stress through the sirtuin1/nuclear factor-erythroid-2-related factor 2/heme oxygenase-1 signaling pathway

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World Journal of Gastroenterology 2024年第20期30卷 2709-2725页

作者： kai-Di Chen Kui-Ling Wang Chen Chen Yi-Jia Zhu Wen-Wen Tang Yu-Ji Wang Ze-Peng Chen Lin-Hai He Yu-Gen Chen Wei Zhang Jiangsu Province hospital of Chinese Medicine The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina The No.1 Clinical Medical College Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Colorectal Surgery Jiangsu Province Hospital of Chinese MedicineThe Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Jiangsu Province Key Laboratory of Tumor Systems Biology and Chinese Medicine The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Jiangsu Collaborative Innovation Center of Chinese Medicine in Prevention and Treatment of Tumor The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina

BACKGROUND Constipation,a highly prevalent functional gastrointestinal disorder,induces a significant burden on the quality of patients'life and is associated with substantial healthcare ***,identifying efficient therapeutic modalities for constipation is of paramount *** stress is a pivotal contributor to colonic dysmotility and is the underlying pathology responsible for constipation ***,we postulate that hydrogen therapy,an emerging and promising intervention,can serve as a safe and efficacious treatment for *** To determine whether hydrogen-rich water(HRW)alleviates constipation and its potential *** Constipation models were established by orally loperamide to Sprague-Dawley *** freely consumed HRW,and were recorded their 24 h total stool weight,fecal water content,and charcoal propulsion *** samples were subjected to 16S rDNA gene *** non-targeted metabolomic analysis,malondialdehyde,and superoxide dismutase levels were *** tissues were stained with hematoxylin and eosin,Alcian blue-periodic acid-Schiff,reactive oxygen species(ROS)immunofluorescence,and immunohistochemistry for cell growth factor receptor kit(c-kit),PGP 9.5,sirtuin1(SIRT1),nuclear factor-erythroid-2-related factor 2(Nrf2),and heme oxygenase-1(ho-1).Quantitative real-time PCR and western blot analysis were conducted to determine the expression level of SIRT1,Nrf2 and ho-1.A rescue experiment was conducted by intraperitoneally injecting the SIRT1 inhibitor,EX527,into constipated ***460 cells were induced with H2O2 and treated with the metabolites to evaluate ROS and SIRT1 *** HRW alleviated constipation symptoms by improving the total amount of stool over 24 h,fecal water content,charcoal propulsion rate,thickness of the intestinal mucus layer,c-kit expression,and the number of intestinal *** modulated intestinal microbiota imbalance and abnormaliti

关键词： Hydrogen-rich water Constipation Sirtuin1 Oxidative stress Gut microbiota Serum metabolites