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A molecular brake hoop for the motion of metal atoms inside fullerene cage

Science China Chemistry 2022年第8期65卷 1601-1606页

作者： Yuxi Lu Chong Zhao Jie Zhang Wang Li Jiayi Liang Linshan liu yongguang Li Chunru Wang Taishan Wang Beijing National Laboratory for Molecular Sciences Key Laboratory of Molecular Nanostructure and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Pharmacy Guizhou Medical UniversityGuian New District 550025China College of Material Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou 311121China

Molecular machines have attracted extensive attention due to their fancy concept and their potential to influence the science and technology.The dynamic motion of encapsulated metallic clusters is a distinctive character for endohedral metallofullerenes.For the development of molecular rotors based on metallofullerenes,the most challenging issue is how to control the motion of untouchable metallic cluster inside fullerene cage.In this work,we report a molecular brake hoop for the motion of metal atoms inside fullerene cage.A cycloparaphenylene of[12]CPP was employed to hoop the metallofullerene and produce two supramolecular complexes of Sc_(3)N@C_(80)⊂[12]CPP and Sc_(2)C_(2)@C_(82)⊂[12]CPP.Moreover,the temperature-dependent ^(45)Sc nuclear magnetic resonance spectroscopy(NMR)was employed to detect the motion of internal Sc_(3)N and Sc_(2)C_(2) clusters.^(45)Sc NMR results reveal that the[12]CPP can slow down the rotation of internal metallic cluster through host-guest interaction,and thus the[12]CPP can be considered as a molecular brake hoop for the internal metal motion of metallofullerenes.Furthermore,by means of this molecular brake hoop,the motion of metal atoms inside fullerene cage have expanded range of velocity.In addition,theoretical calculations on Sc_(3)N@C_(80)⊂[12]CPP were executed to illustrate the molecular orientation as well as internal Sc_(3)N rotation.This study would promote the research of endohedral metallofullerene as a molecular rotor.

关键词： metallofullerene molecular rotor molecular brake supramolecular complex dynamic motion

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“十里洋场”——晚清上海文人城市记忆的重构

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汉语言文学研究 2024年第2期15卷 17-30页

作者：刘永广南京信息工程大学马克思主义学院

外滩作为一处空间的所在,虽然身处洋场的中西人士都可以经常性的出入其间,但是它的出现与存在,对于西人与华人却有着完全不同的意义。不同于西人将外滩视为自身殖民权威展示的场所,晚清时期,华人对这一空间的认知经历了从讶异到接受再... 详细信息

外滩作为一处空间的所在,虽然身处洋场的中西人士都可以经常性的出入其间,但是它的出现与存在,对于西人与华人却有着完全不同的意义。不同于西人将外滩视为自身殖民权威展示的场所,晚清时期,华人对这一空间的认知经历了从讶异到接受再到重构其形象的历程。通过日常体验、文本再现与图像重构,上海文人将外滩作为一种超验性空间锚定在集体记忆之中,作为大众日常经验中的地理符号,重塑了离散的都市集体身份意识与社会记忆,外滩也由一处奇异的景观在地化为上海城市的地标性景观。

关键词：外滩空间记忆重构

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Optimal flight parameters of unmanned helicopter for tea plantation frost protection

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International Journal of Agricultural and Biological Engineering 2015年第5期8卷 50-57页

作者： Hu yongguang liu Shengzhong Wu Wenye Wang Jizhang Shen Jianwen School of Agricultural Equipment Engineering Jiangsu UniversityZhenjiang 212013China Electronic Application Laboratory of Wuxi Hanhe Unmanned Helicopters Wuxi 214135China

To determine proper flight parameters of an unmanned helicopter for tea plantation frost protection,field experiments were conducted to study the impact of flight height,speed and interval on airflow disturbance and temperature rise around tea canopies based on the analysis and simulation of frost protection with a certain helicopter.The relationship between temperature rise after flight and the above flight parameters was established through a regression orthogonal experiment,based on which the optimal combination of flight parameters was obtained through the single-factor golden section method.The results showed that wind speed around tea canopies decreased with the increase of flight height when flight speed was constant.There was a multivariate linear relationship between temperature rise and flight parameters,and the sequence of flight parameters’influence on frost protection effect was flight interval,flight height,flight speed.The optimal combination of flight parameters were flight height of 4.0 m,flight speed of 6.0 m/s and flight interval of 20 min.After the flight with the above parameters air temperature around tea canopies increased 1.6℃ when background thermal inversion strength was 3.8℃.

关键词： thermal inversion frost protection unmanned helicopter flight parameters orthogonal experiment single-factor golden section method tea plants

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Sprinkler irrigation system for tea frost protection and the application effect

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International Journal of Agricultural and Biological Engineering 2016年第5期9卷 17-23页

作者： Hu yongguang Zhao Chen liu Pengfei Asante Eric Amoah Li Pingping Key Laboratory of Modern Agricultural Equipment and Technology Jiangsu UniversityZhenjiang 212013China College of Biology and the Environment Nanjing Forestry UniversityNanjing 210037China

A sprinkler irrigation system was designed and applied for a tea field to achieve frost protection through latent heat release when water turning into ice.Frost protection effects during night were tested at different irrigation application rates by monitoring air temperature around tea canopy(Tc).Temperature sensors were arranged at different distances from the sprinkler.The preliminary results showed that,when the sprinkler system worked continuously at the application rate of 2-4 mm/h before sunrise,tea canopy was covered with ice and Tc remained around 0℃,preventing tea plants from frost damage.But no more temperature rise was obviously observed at the application rates above 4 mm/h,which means less cost effectiveness.The system was stopped after sunrise when background air temperature rose back to 0℃and Tc increased by 2.2℃in one hour,while Tc of non-irrigated area increased by 4.8℃,which might cause thawing injuries to tea plants.The leaf surface temperature was lower than Tc,and the difference between the leaf surface temperature and Tc decreased with the increase of application rate.Therefore,the sprinkler irrigation system could achieve tea frost protection,and the recommended application rate was 2-4 mm/h for better protection effect.The system should keep running throughout frost night till half an hour after sunrise.The start and stop of the sprinkler irrigation system should be controlled based on Tc.

关键词： sprinkler irrigation frost protection Camellia Sinensis L application rate temperature rise frost damage

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Water chemistry controlled aggregation and photo-transformation of silver nanoparticles in environmental waters

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Journal of Environmental Sciences 2015年第8期27卷 116-125页

作者： yongguang Yin Xiaoya Yang Xiaoxia Zhou Weidong Wang Sujuan Yu Jingfu liu Guibin Jiang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences School of the Environment Jiangsu University Institute of Environment and Health Jianghan University

The inevitable release of engineered silver nanoparticles（Ag NPs） into aquatic environments has drawn great concerns about its environmental toxicity and safety. Although aggregation and transformation play crucial roles in the transport and toxicity of Ag NPs, how the water chemistry of environmental waters influences the aggregation and transformation of engineered Ag NPs is still not well understood. In this study, the aggregation of polyvinylpyrrolidone（PVP） coated Ag NPs was investigated in eight typical environmental water samples（with different ionic strengths, hardness, and dissolved organic matter（DOM） concentrations） by using UV–visible spectroscopy and dynamic light scattering. Raman spectroscopy was applied to probe the interaction of DOM with the surface of Ag NPs. Further, the photo-transformation and morphology changes of Ag NPs in environmental waters were studied by UV–visible spectroscopy, inductively coupled plasma mass spectrometry, and transmission electron microscopy. The results suggested that both electrolytes（especially Ca2＋and Mg2＋） and DOM in the surface waters are key parameters for Ag NP aggregation, and sunlight could accelerate the morphology change, aggregation, and further sedimentation of Ag NPs. This water chemistry controlled aggregation and photo-transformation should have significant environmental impacts on the transport and toxicity of Ag NPs in the aquatic environments.

关键词： Silver nanoparticles（AgNPs） Aggregation Transformation Water chemistry Sunlight

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Control system of a performance test-bed for frost protection wind machines

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International Journal of Agricultural and Biological Engineering 2016年第6期9卷 36-43页

作者： Hu yongguang liu Ping Asante Eric Amoah Wu Wenye Li Pingping Key Laboratory of Modern Agricultural Equipment and Technology Jiangsu UniversityZhenjiang 212013China College of Biology and the Environment Nanjing Forestry UniversityNanjing 210037China

To test the performance and optimize operational parameters of various frost protection wind machines,a control system of performance test-bed was designed and developed based on Programmable Logic Controller(PLC)and touch screen.The system realized automatic control of operational parameters including hydraulic platform height,impeller rotation speed,depression angle,rotation range and cycle.Field case study results shows that the control accuracy of all the parameters was achieved with the average errors of 2.11 cm for height,9.5 r/min for impeller rotation speed,0.83°for pan-tilt rotation range and 0.061 min for rotation cycle.With the control of the test-bed,the performances of various wind machines,such as the distribution of airflow and temperature,and frost protection effect,could be tested under various working conditions,which provide experiment supports for developing wind machines adapted to different conditions with higher frost protection effect.

关键词： frost protection wind machines performance test-bed design control PLC

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Hydroxyl radical formation upon dark oxidation of reduced iron minerals: Effects of iron species and environmental factors

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Chinese Chemical Letters 2019年第12期30卷 2241-2244页

作者： Ailing Zhu Yingying Guo Guangliang liu Maoyong Song Yong Liang Yong Cai yongguang Yin Institute of Environment and Health Jianghan UniversityWuhan 430056China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Laboratory of Environmental Nanotechnology and Health Effect Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Chemistry and Biochemistry Florida International UniversityMiamiFL 33199United States

Dark formation of hydroxyl radical upon oxidation of reduced iron minerals plays an important role in the degradation and transformation of organic and inorganic pollutants.Herein,we compared the hydroxyl radical formation from various reduced iron minerals at different redox conditions.·OH production was generally observed from the oxidation of reduced iron minerals,following the order:mackinawite(FeS)>reduced nontronite(iron-bearing smectite clay)> pyrite(FeS2)> side rite(FeCO3).Structural Fe^2+ and dissolved O2 play critical roles in ·OH production from reduced iron minerals.·OH production increases with decreasing pH,and Cl^-has little effect on this process.More importantly,dissolved organic matter significantly enhances ·OH production,especially under O2 purging,highlighting the importance of this process in ambient environments.This sunlight-independent pathway in which ’OH forms during oxidation of reduced iron minerals is helpful for understanding the degradation and transformation of various inorganic and organic pollutants in the redox-fluctuation environments.

关键词： Reduced iron minerals Hydroxyl radical Dark oxidation Mackinawite Dissolved organic matter

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Rational design of platinum(Ⅱ)complexes with orthogonally oriented triazolyl ligand with emission enhancement characteristics for cancer chemotherapy in vivo

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Science China Chemistry 2023年第10期66卷 2878-2884页

作者： Yeye Ai Zherui Zhang Yuexuan Fei Ruirong Ye Angela Sin-Yee Law Zong-Wan Mao Junqiu liu yongguang Li Vivian Wing-Wah Yam Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education College of Material Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou 311121China Institute of Molecular Functional Materials State Key Laboratory of Synthetic Chemistry and Department of ChemistryThe University of Hong KongHong KongChina School of Chemistry Sun Yat-Sen UniversityGuangzhou 510275China State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun 130012China

The mitochondria are essential for tumorigenesis and have been regarded as important targets in cancer chemotherapy.Herein,the mitochondria-targeted platinum(Ⅱ)complexes have been prepared.The introduction of the triazole group with larger steric hindrance through post-click reaction converts the hybridization of carbon from sp to sp^(2),endowing the complexes with an orthogonally oriented ligand with restricted rotation and emission enhancement characteristics.Methylation of the triazolyl ligand has led to platinum(Ⅱ)complexes that can efficiently enter cancer cells and selectively accumulate in mitochondria,leading to significant enhancement in phosphorescence.In vivo anti-cancer investigations have demonstrated their distinct antitumor efficacy in substantial inhibition of tumor growth in breast cancer mice through dissipation of mitochondrial membrane potential,inducing apoptosis of tumor cell with negligibly systemic cytotoxicity.

关键词： platinum(Ⅱ)complexes post-click reaction emission enhancement mitochondria-targeting antitumor

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Chromatin remodeling factor lymphoid.specific helicase inhibits ferroptosis through lipid metabolic genes in lung cancer progression

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Chinese Journal of Cancer 2017年第12期36卷 669-671页

作者： Yiqun Jiang Yuchen He Shuang liu yongguang Tao Key Laboratory of Carcinogenesis and Cancer Invasion Ministry of EducationXiangya HospitalCentral South UniversityChangsha 410008HunanP.R.China Key Laboratory of Carcinogenesis Ministry of HealthCancer Research InstituteSchool of Basic MedicineCentral South UniversityChangsha 410078HunanP.R.China Institute of Medical Sciences Xiangya HospitalCentral South UniversityChangsha 410008HunanP.R.China Department of Thoracic Surgery Second Xiangya HospitalCentral South UniversityChangsha 410011HunanP.R.China

Ferroptosis, a novel mode of non-apoptotic cell death,involves a metabolic dysfunction that results in the production of iron-dependent reactive oxygen species (ROS),an iron carrier protein (transferrin), intracellular metabolic process, and related regulators (e.g., p53 protein).Previous studies have linked ferroptosis with oncogenic Ras [1], and p53 tumor suppressor positively regulates ferroptosis by transcriptionally inhibiting the expression of the cysteine/glutamate antiporter, which is encoded by the SLC7A11 gene in human [1, 2]. Whether other factors such as epigenetic factors are involved in the process remains less known.Chromatin modifier lymphoid specific helicase (LSH)contributes to the malignant progression of nasopharyngeal carcinoma and glioma [3]. We recently indicated that LSH was shown to co-operate with partners, such as G9a, to drive cancer progression [4, 5].

关键词： Ferroptosis, a novel mode of non-apoptotic cell death

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Solid Component Fraction in Multi-Phase Flows Using Electrical Resistance Tomography and Kalman Filter

Solid Component Fraction in Multi-Phase Flows Using Electric...

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第三十九届中国控制会议

作者： liu Yang Shihong Yue yongguang Tan School of Electrical and Information Engineering Tianjin University

One of the major tasks in multi-phase flow detection is solid component fraction calculation.According to the Electrical Resistance Tomography(ERT) measurement,the mainstream method is to use Maxwell-Garnett formula to derive solid component fraction of multi-phase flow from conductivity.In dredging engineering fields,measurement data of multiphase flows in horizontal and vertical ducts is typically obtained by two sensor planes.However,the estimated solid component fraction remains rather inaccurate due to linear back projection(LBP) algorithm limitation,and noisy data on the available ERT measurements in most cases.In this paper,we proposed a new solid component fraction estimation method according to Kalman filter and ERT.This new method uses the complementarity of dual sensor data to improve measurement accuracy.Facing the real needs in dredging engineering fields,solid component fraction of the typical flow were tested.The results validate our proposed methods in a series of typical flow conditions.

关键词： Electrical Resistance Tomography component fraction Kalman filter Multiphase flow

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