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Diterpenoid Alkaloids from Aconitum Pendulum

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Chinese Chemical Letters 1997年第11期8卷 967-970页

作者： zhang, sm Tan, LQ Ou, QY Chinese Acad Sci Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China

A new diterpenoid 12-epiacetyldehydrolucidusculline (1) and a new norditerpenoid alkaloid 2-hydroxydeoxyaconitine (2) were isolated from the roots of Aconitum pendulum, together with eight known alkaloids aconitine (3), deoxyaconitine (4), 3-acetylaconitine (5), 12-epiacetyldehydronapelline (6), dehydrolucidusculline (7), dehydronapelline (8). 12-epidehydronapelline (9), and noeline (10). The structures of the new alkaloids (1-2) were determined on the basis of spectral method.

关键词： NUCLEAR MAGNETIC-RESONANCE

Eremophilenolides from Cacalia Roborowskii

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Chinese Chemical Letters 1998年第1期9卷 65-68页

作者： zhang, sm Zhao, GL Lin, GQ Chinese Acad Sci Shanghai Inst Organ Chem Shanghai 200032 Peoples R China

From the extracts of the roots of Cacalia roborowskii (Maxim) Ling, five new eremophilenolides were isolated and their structures identified as 8 beta, 10 beta-dihydroxy-6 beta-methoxyleremophilenolide (1), 3 beta-acetoxyl-8 beta, 10 beta -dihydroxy-6 beta-methaxyeremophilenolide (2), 3 beta-angeloyloxy-8 beta-, 10 beta-dihydroxy-6 beta-methoxyeremophilenolide (3), 3 beta-(2-methylbutyryloxy)-8 beta, 10 beta-dihydroxy-6 beta-methoxyeremophilenolide (4), and 8 beta-hydroxy-6 beta-methoxyeremophil-7(11), 9-dien-8, 12-olide(5), based on 1D and 2D NMR experiments.

关键词： eremophilenolide root herb Cacalia roborowskii (maxim) Ling

Eremophilane Sesquiterpenes from Cacalia Roborowskii

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Chinese Chemical Letters 1998年第1期9卷 61-64页

作者： zhang, sm Zhao, GL Li, R Lin, GQ Chinese Acad Sci Shanghai Inst Organ Chem Shanghai 200032 Peoples R China

Four new eremophilane type sesquiterpenes were isolated from the roots of Cacalia roborowskii (Maxim) Ling. Their structures were established as 8-oxo-eremophila-6, 9-dien-12-oic acid (1), 3 beta-acetoxyl-8-oxo-eremophila-6, 9-dien-12-oic acid (2), 3 beta-angeloyoxyl-8-oxo-eremophilad, 9-dien-12-oic acid (3) and 3 beta-(2-methylbutyryloxyl)-8-oxo-eremophilia-6,9-dien-12-oic acid (4) by means of 1D and 2D NMR spectroscopy.

关键词： eremophilane sesquiterpene Cacalia roborowskii

PLK1 phosphorylation of ZW10 guides accurate chromosome segregation in mitosis

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Journal of Molecular Cell Biology 2024年第2期16卷 47-62页

作者： sm Faysal Bellah Fangyuan Xiong Zhen Dou Fengrui Yang Xing Liu Xuebiao Yao Xinjiao Gao Liangyu zhang MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics Hefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of China School of Life SciencesHefei 230027China Anhui Key Laboratory for Cellular Dynamics and Chemical Biology Hefei 230027China

Stable transmission of genetic information during cell division requires faithful chromosome *** evidence has demonstrated that polo-like kinase 1(PLK1)dynamics at kinetochores control correct kinetochore–microtubule attachments and subsequent silencing of the spindle assembly ***,the mechanisms underlying PLK1-mediated silencing of the spindle checkpoint remain ***,we identified a regulatory mechanism by which PLK1-elicited zeste white 10(ZW10)phosphorylation regulates spindle checkpoint silencing in ***10 is a cognate substrate of PLK1,and the phosphorylation of ZW10 at Ser12 enables dynamic ZW10–Zwint1 *** of ZW10 phosphorylation resulted in misaligned chromosomes,while persistent expression of phospho-mimicking ZW10 mutant caused premature anaphase,in which sister chromatids entangled as cells entered *** findings reveal the previously uncharacterized PLK1–ZW10 interaction through which dynamic phosphorylation of ZW10 fine-tunes accurate chromosome segregation in mitosis.

关键词： ZW10 PLK1 kinetochore mitosis phosphorylation

Interaction between inflammatory bowel disease,physical activity,and myokines:Assessment of serum irisin levels

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World Journal of Gastroenterology 2024年第22期30卷 2923-2926页

作者： Marwan sm Al-Nimer Department of Therapeutics and Clinical Pharmacology College of MedicineUniversity of DiyalaBaqubah 32001Iraq

Inflammatory bowel disease(IBD),including Crohn’s disease and ulcerative colitis,showed a wide spectrum of intestinal and extra-intestinal manifestations,which rendered the patients physically inactive and impaired their quality of *** has been found that physical activity is a non-pharmacological intervention that improves the quality of life for those *** is one member of the myokines secreted by muscle contraction during exercise and could be used as an antiinflammatory biomarker in assessing the physical activity of IBD *** addition,experimental studies showed that exogenous irisin significantly decreased the inflammatory markers and the histological changes of the intestinal mucosa observed in experimental ***,irisin produces changes in the diversity of the ***,endogenous or exogenous irisin,via its anti-inflammatory effects,will improve the health of IBD patients and will limit the barriers to physical activity in patients with IBD.

关键词： Irisin Inflammatory bowel disease Physical activity Myokines Prognostic marker

Diatomic Pd catalyst with conjugated backbone for synergistic electrochemical CO_(2)reduction

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Nano Research 2024年第6期17卷 4850-4855页

作者： Wenxuan zhang Mengran zhang Hongjuan Wang Wen zhang Min zhang MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion School of Chemistry and Chemical EngineeringTianjin University of TechnologyTianjin 300384China

Double-site catalysts have attracted widespread attention in the field of electrocatalysis due to their high metal loading,adjustable active centres,and electronic valence ***,the development of bimetallic sites catalysts that coordinate with definite atoms is still in the exploratory ***,we designed and synthesized a bimetallic palladium complex(BPB-Pd_(2))with conjugated *** supported BPB-Pd_(2)was applied to electrochemical CO_(2)reduction reaction(CO_(2)RR)for the first *** as-obtained BPB-Pd_(2)gives an exceptional Faradaic efficiency of CO(FECO)of 94.4%at−0.80 V *** hydrogen electrode(RHE),which is significantly superior to monoatomic palladium catalyst(BPB-Pd1).The density functional theory(DFT)calculations revealed that the essential reason for the outstanding activity of BPB-Pd_(2)toward CO_(2)RR was that the electronic effect between diatomic palladium reduces the free energy change for CO_(2)RR ***,BPB-Pd_(2)exhibits moderate free energy change to form COOH*intermediate,which was beneficial for the generation of CO in CO_(2)RR.

关键词： synthesis electrocatalysis CO_(2)reduction bimetallic palladium complex synergistic catalysis

N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-C_(3)N_(4) nanotube composite photocatalysts for antibiotic photodegradation and H2 production

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 165-178页

作者： Jingshu Yuan Yao zhang Xiaoyan zhang Junjie zhang Shen’gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Xi’an Fanyi University Xi’an 710105China Shunde Graduate School of University of Science and Technology Beijing Foshan 528399China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SAR 820000China

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-C_(3)N_(4) nanotube (PCN) composite photocatalysts (denoted as G-TPCN). The optimal sample (G-TPCN doped with 0.1wt% N-GQD, denoted as 0.1% G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1% G-TPCN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO_(2), PCN, and N-TiO_(2)/PCN(TPCN-1), respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO_(2) and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Compared with those of N-TiO_(2), PCNs, and TPCN-1, the H2 production activity of 0.1%G-TPCN under visible light is enhanced by 12.4, 2.3, and 1.4times, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1% G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1% G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion.

关键词： N-doped TiO_(2) N-doped graphene quantum dots P-doped g-C_(3)N_(4) porous hollow nanotube heterojunction photocatalysis

Reversing free-electron transfer of sulfide cocatalyst for exceptional photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第4期171卷 147-149页

作者： Yanfeng zhang Zhenyi zhang National Experimental Chemistry Teaching Center Hebei Key Laboratory of Inorganic Nano-materialsCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S ***,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and *** anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.

关键词： Photocatalysis Cocatalyst Electron reversal Antibonding-orbital occupancy S–H bonds

Friction as energy dissipation process associated with superlubricity of solids

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Friction 2024年第9期12卷 2083-2088页

作者： Bo zhang Saga University Saga-shi 840-8502Japan

The paper shows that work in a quantum system is quantized with energy;the quantum work is equivalent to the highest eigenenergy(the Debye energy)of the system and the superlubricity of solids is derived from the quantum *** prerequisite for the superlubricity is that the lateral force at contact surfaces in sliding is less than the Debye force so that the phonon of the solids is not excited.

关键词： superlubricity phonon friction Plank law Debye frequency