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Science China Chemistry 2021年第7期64卷 1177-1183页

作者： Zi-En Zhang Yuan-Yuan An Bo Zheng jin-ping chang Ying-Feng Han College of Chemistry and Materials Science Northwest UniversityXi'an 710127China School of Pharmaceutical Sciences Nanjing Tech UniversityNanjing 211816China

The hierarchical self-assembly(HSA) strategy widely utilized in biological systems has been applied in artificial systems to orchestrate small building blocks into complex functional architectures. The non-interfering interactions glue various building blocks together and produce new species with attractive properties. Herein, we functionalized NHC-based assemblies with orthogonal host–guest interaction to fabricate metal-carbene based supramolecular polymer gel. A series of unique crown etherappended cylinder-like trinuclear AuIhexacarbene assemblies [Au_(3)(L)_(2)](PF_(6))_(3)(L=D1–D4, A1–A4) were synthesized from the corresponding trisimidazolium salts H_(3)-L(PF_(6))_(3)(L=D1–D4, A1–A4) in which the N-wingtip of the imidazole moieties were substituted with three identical crown ether groups of different sizes(B15C5, B18C6, B21C7, DB24C8). The gold carbene assembly is able to complex six ammonium salts without disrupting the underlying metal-carbene cylinders. In addition, the supramolecular polymer metallogel featuring a multiple-responsiveness can be formed by using [Au_(3)(A_(4))_(2)](PF_(6))_(3) appended with DB24C8 as the core and bisammonium salt as the cross-linker. The case of introducing orthogonal interaction to NHC moiety by N-wingtip substitution demonstrates the feasibility and the power of such strategy to expand the NHC-based supramolecular system and endow them with novel properties.

关键词： N-heterocyclic carbene metallogel crown ether orthogonal interaction

A trefoil-shaped macrocycle with [12]-imidazolium cations

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Chinese Chemical Letters 2022年第10期33卷 4567-4571页

作者： Le Zhang Li-Ying Sun jin-ping chang Hui-Yu Xie Ya-Wen Zhang Yi-Fan Zhang Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi'an 710127China

A trefoil-like two-dimensional(2D)C_(3v) symmetric organic[12]-imidazolium cation H_(12)-2(PF_(6))_(12) featuring three[4]-imidazolium macrocycles was synthesized in three *** reaction of a dodecakis H_(12)-1(PF_(6))_(12) imidazolium salt with Ag_(2)O resulted in the formation of a hexanuclear AgI dodecacarbene assembly[Ag_(6)(1)](PF_(6))_(6).Upon UV irradiation,the photodimerization of the cinnamic ester pendants of[Ag_(6)(1)](PF_(6))_(6) led to the generation of a trefoil-like complex[Ag_(6)(2)](PF_(6))_(6) containing three closed *** of metal ions allowed for the synthesis of the target *** complexes were fully characterized by NMR spectroscopy(^(1)H,^(13)C{^(1)H}and 2D NMR)and high-resolution electrospray ionization mass spectrometry(HR-ESI-MS).

关键词： Trefoil-shaped macrocycle N-Heterocyclic carbenes Photochemical reaction Imidazolium

Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen Tang Sai Zhang FuLiang Xiao HongMing Yang Si Liu YiHua He chang Yang YuYue jin ZhouKun Deng ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation(AKR)is a common radio emission,which can contribute to the magnetosphere−ionosphere−atmosphere *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500−4500 km and invariant latitude(|ILAT|)=60°−80°has been analyzed.63045 AKR samples have been identified with~48%(52%)samples on the dayside(nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05−08 and 18−22(02−05 and 12−17)in the northern(southern)*** distinct MLT asymmetry is associated with the direction of Bxof the interplanetary magnetic *** addition,the occurrence rate on the nightside clearly increases as the index *** study further enriches *** and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field

广西师范学院体育教育专业的发展现状与对策研究

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广西师范学院学报（哲学社会科学版） 2007年第S2期28卷 8-11,15页

作者：靳卫平李昌瑞广西师范学院体育系广西南宁530023

通过对广西师范学院体育教育专业04、05、06级的264名学生进行调查,分析我系体育教育专业建设中存在的问题,探讨体育教育专业建设思路,以提高体育教育专业人才培养质量,促进体育系更好的发展。

关键词：体育教育专业现状存在问题

(-)-Epigallocatechin-3-gallate inhibits growth of gastric cancer by reducing VEGF production and angiogenesis

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World Journal of Gastroenterology 2007年第8期13卷 1162-1169页

作者： Bao-He Zhu, Wen-Hua Zhan, Zheng-Rong Li, Zhao Wang, Yu-Long He, Jun-Sheng Peng, Shi-Rong Cai, jin-ping Ma, chang-Hua Zhang, Department of Gastrointestinal & Pancreatic Surgery, First Affiliated Hospital, Sun Yat-Sen University Gastric Center of Sun Yat-Sen University, Guangzhou 510080, Guangdong Province, China Department of Gastrointestinal & Pancreatic Surgery First Affiliated Hospital Sun Yat-Sen University Gastric Center of Sun Yat-Sen University Guangzhou 510080 Guangdong Province China. wenhuazhanwcwk@***

AIM： To investigate the effect of （-）-epigallocatechin-3-gallate （EGCG） on growth of gastric cancer and its possible mechanism. METHODS： Heterotopic tumors were induced by subcutaneously injection of SGC-7901 cells in nude mice. Tumor growth was measured by calipers in two dimensions. Tumor angiogenesis was determined with tumor microvessel density （MVD） by immunohistology. Vascular endothelial growth factor （VEGF） protein level and activation of signal transducer and activator of transcription 3 （Star3） were examined by Western blotting. VEGF mRNA expression was determined by RT-PCR and VEGF release in tumor culture medium by ELISA. VEGF-induced cell proliferation was studied by MTT assay, cell migration by gelatin modified Boyden chamber （Transwell） and in vitro angiogenesis by endothelial tube formation in Matrigel. RESULTS： Intraperitoneal injection of EGCG inhibited the growth of gastric cancer by 60.4%. MVD in tumor tissues treated with EGCG was markedly reduced. EGCG treatment reduced VEGF protein level in vitro and in vivo. Secretion and mRNA expression of VEGF in tumor cells were also suppressed by EGCG in a dose-dependent manner. This inhibitory effect was associated with reduced activation of Star3, but EGCG treatment did not change the total Star3 expression. EGCG also inhibited VEGF-induced endothelial cell proliferation, migration and tube formation. CONCLUSION： EGCG inhibits the growth of gastric cancer by reducing VEGF production and angiogenesis, and is a promising candidate for anti-angiogenic treatment of gastric cancer.

关键词： Epigallocatechin-3-gallate Angiogenesis Migration Tube formation Vascular endothelial growth factor Signal transducer and activator of transcription 3 Gastric cancer

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen chang-Jiang Yao Yuan-Yuan Zhu Liang-jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

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A review of the health effects and exposure-responsible relationship of diesel particulate matter for underground mines

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International Journal of Mining Science and Technology 2017年第5期27卷 831-838页

作者： chang ping Xu Guang Department of Mining Engineering and Metallurgical Engineering Western Australian School of MinesCurtin UniversityKalgoorlie 6430Australia

The increasing use of diesel-powered equipment in confined spaces(underground mines) has the potential to over expose underground miners under the threat of diesel particulate matter(DPM). Miners in underground mines can be exposed to DPM concentrations far more than works in other industries. A great number of animal and epidemiological studies have shown that both short-term and long-term DPM exposure have adverse health effect. Based on reviews of related studies, especially some recent evidence, this paper investigated the long and short-term health effects based on animal studies and epidemiological studies. The exposure-response relationship studies were also explored and compared to the current DPM regulation or standards in some countries. This paper found that the DPM health effect studies specifically for miners are not sufficient to draw solid conclusions, and a recommendation limit of DPM concentration can be put in place for better protection of miners from DPM health risk. Current animal studies lack the use of species that have similar lung functions as human for understanding the cancer mode of action in human. And finally, the DPM health hazard will continue to be a challenging topic before the mode of action and reliable exposure-response relationship are established.

关键词： Diesel particulate matter (DPM) Underground mines Lung cancer Exposure-response relationship

A novel 8,4'-oxyneolignan diglycoside from Ligusticum sinensis

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Chinese Chemical Letters 2011年第12期22卷 1454-1456页

作者： Jian ping Ma chang Heng Tan Da Yuan Zhu Ling jin College of Life Science and Technology Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Drug Research Institute of Materia MedicaShanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 201203China Department of Pharmacy Gansu College of Traditional Chinese MedicineLanzhou 730000China

A novel 8,4＇-oxyneolignan diglycoside,named ligusinenoside d（1）,was isolated from the rhizomes of Ligusticum sinensis, together with five known analogues *** absolute configurations of 1 and 2 were elucidated by me... 详细信息

关键词： Ligusticum sinensis Oliv. 8 4'-Oxyneolignan diglycoside Ligusinenoside D

A novel tuned heave plate system for heave motion suppression and energy harvesting on semi-submersible platforms

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Science China(Technological Sciences) 2016年第6期59卷 897-912页

作者： LIU Kun OU jin ping School of Civil Engineering Harbin Institute of Technology Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Institute of Ocean Deep Water Engineering Dalian University of Technology

Deepwater offshore structures such as semi-submersible platforms suffer powerful ocean waves due to their location and site condition. The long distance away from the shore also brings many difficulties to energy supply for the platform operation. How to reduce the response of the platform and convert the wave energy into electrical power is a meaningful topic. In this paper, a tuned heave plate system(THP) is presented and designed to be employed on a semi-submersible platform for heave motion suppression and energy harvesting. This THP system is composed of spring supports, a power take-off system(PTO), and a heave plate. The PTO system is a permanent magnet linear generator(PMLG), which could directly convert the kinetic energy of the heave plate into electronic power. The stiffness of the spring supports is designed based on the principle of the tuned mass damper(TMD). The numerical model of the platform and the THP system is established according to the hydrodynamic analysis results of the platform. The model is tested and modified by scale model tests on the platform in the wave tank. A parameter study, including the size, tuned period, and damping ratio of the THP system, is conducted systematically based on the numerical model. The optimal parameters of the THP are selected due to the maximum heave motion reduction under severe wave conditions in South China Sea. The performance of the semi-submersible with and without the THP system under different wave conditions is analyzed. It is demonstrated that this novel tuned heave plate system could reduce the heave motion of the semi-submersible platform significantly and generate considerable power, which makes the THP system have a broad prospect for development.

关键词： heave motion semi-submersible wave energy harvesting wave energy converter TMD

Recent Progresses of the DAMPE Mission

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空间科学学报 2024年第4期44卷 633-642页

作者： chang jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033 School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026

The DArk Matter Particle Explorer(DAMPE)is a space high-energy particle andγ-ray detector whose major scientific goals are the indirect detection of dark matter particles,the origin of cosmic rays and highenergyγ-ray *** its successful launch in December 2015,the DAMPE has been operated smoothly in orbit for more than 8 *** direct measurements of the boron-to-carbon and boron-to-oxygen flux ratios,and the proton+Helium spectrum up to 316 TeV have been obtained,revealing new spectral features with very high *** search results ofγ-ray spectral line and fractionally charged particles indicate a good potential of DAMPE for indirect dark matter detection and new physical discovery in *** DAMPE measurements are expected to significantly advance our understanding of the fundamental problems in astroparticle physics.

关键词： DAMPE Dark matter Indirect detection Cosmic rays