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Evaluation of Stabilization Performances of Antioxidants in Poly(ether ether ketone)

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Chemical Research in Chinese Universities 2012年第5期28卷 907-911页

作者： ZHOU Zheng ZHOU Fu-gui ZHANG Shu-ling MU Jian-xin yue Xi-gui WANG gui-bin High Performance Plastics Engineering Research Center Ministry of EducationCollege of ChemistryJilin UniversityChangehun 130012P.R.China

Two types of antioxidants（a primary antioxidant and a secondary antioxidant） were used to improve the stability of poly（ether ether ketone）（PEEK）. The effects of the antioxidants on the properties of PEEK and the stabilization mechanism were investigated by some characterization methods, such as rheometer, thermogravimetric ana- lysis（TGA）, universal tester and electron spin resonance（ESR）. The results indicate that the efficiency of the phosphorous antioxidant（DS） in improving the stability of PEEK was better than that of the phenolic antioxidant（DN） in both melting stability and thermal stability, and the thermal stability of PEEK sample containing 0.07%（mass fraction） DS was the best among all the samples due to the decrease of the free radicals density, as proven by ESR measurement. Additionally, no obvious changes could be observed in mechanical properties of PEEK containing antioxidants compared to those of virgin PEEK.

关键词： Poly(ether ether ketone) Antioxidant Stability Mechanical property Radical

A Novel Ni-capped Silverton-type Complex: H_4{[Ni(H_2O)_3]_2[CeMo_(12)O_(42)]}·13.5H_2O

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Chinese Journal of Structural Chemistry 2006年第2期25卷 204-208页

作者： WANG Jing-Ping SHEN yue GUO gui-Ling NIU Jing-Yang School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China

A novel Ni-capped complex H4{[Ni（H2O）3]2[CeMo12O42] }· 13.5H2O has been synthesized, which is the first Silverton-type anion capped with two Ni units via three terminal oxygen atoms. Crystallographic data for the title compound： Trigonal, space group R-3, a = 13.0950（19）, b = 13.0950（19）, c = 33.029（7） A, α = β= γ = 58.727（17）A °, V = 4905.1（14） A °^3, Z = 3, Mr= 2437.17, Dc = 2.475 g/cm^3, F（000） = 3462, T = 293（2） K, μ（MoKa） = 3.564 mm^-1, Rt = 0.0369, wR2 = 0.0905 and GOF= 1.079 for 151 parameters and 1963 reflections with I 〉 2σ（I） in the range of 1.85≤θ≤25.50°.

关键词： crystal structure Silverton-type Ni-capped

Numerical study on three-dimensional flow field of continuously rotating detonation in a toroidal chamber

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Acta Mechanica Sinica 2012年第1期28卷 66-72页

作者： Xu-Dong Zhang Bao-Chun Fan Ming-yue gui Zhen-Hua Pan Gang Dong Science and Technology on Transient Physics LaboratoryNanjing University of Science and Technology 210094 NanjingChina State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology100081 BeijingChina

Gaseous detonation propagating in a toroidal chamber was numerically studied for hydrogen/oxygen/nitrogen mixtures. The numerical method used is based on the three-dimensional Euler equations with detailed finiterate chemistry. The results show that the calculated streak picture is in qualitative agreement with the picture recorded by a high speed streak camera from published literature. The three-dimensional flow field induced by a continuously rotating detonation was visualized and distinctive features of the rotating detonations were clearly depicted. Owing to the unconfined character of detonation wavelet, a deficit of detonation parameters was observed. Due to the effects of wall geometries, the strength of the outside detonation front is stronger than that of the inside portion. The detonation thus propagates with a constant circular velocity. Numerical simulation also shows three-dimensional rotating detonation structures, which display specific feature of the detonation- shock combined wave. Discrete burning gas pockets are formed due to instability of the discontinuity. It is believed that the present study could give an insight into the interest- ing properties of the continuously rotating detonation, and is thus beneficial to the design of continuous detonation propulsion systems.

关键词： Continuously rotating detonation - Three- dimensional flow field structure - Numerical study Detonation parameters deficit ~ Effects of wall geometries

Nonlinear Dynamical Behavior in Neuron Model Based on Small World Network with Attack and Repair Strategy

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Communications in Theoretical Physics 2008年第4期49卷 965-970页

作者： YANG Qiu-Ying ZHANG Ying-yue ZHANG gui-Qing CHEN Tian-Lun Department of Physics Nankai University Tianjin 300071 China

In this paper, we investigate the effect due to the change of topology structure of network on the nonlinear dynamical behavior, by virtue of the OFC neuron evolution model with attack and repair strategy based on the small world. In particular, roles of various parameters relating to the dynamical behavior are carefully studied and analyzed. In addition, the avalanche and EEC-like wave activities with attack and repair strategy are also explored in detail in this work.

关键词： attack repair self-organized criticality small world network

Self-organized Critical Model Based on Complex Brain Networks with Hierarchical Organization

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Communications in Theoretical Physics 2008年第9期50卷 681-684页

作者： ZHANG Ying-yue ZHANG gui-Qing YANG Qiu-Ying CHEN Tian-Lun Department of Physics Nankai University Tianjin 300071 China

The dynamical behavior in the cortical brain network of macaque is studied by modelling each cortical areawith a subnetwork of interacting excitable *** find that the avalanche of our model on different levels *** the... 详细信息

关键词： self-organized criticality hierarchical organization power-law cortical network refractory-period

Efficient photocatalytic reduction of CO_(2)to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期68卷 152-156页

作者： Lihua Zhang Lingjing Chen Huatian Shi yue Wei gui Chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental EngineeringDongguan University of TechnologyDongguan 523808China Department of Chemistry and Institute of Molecular Functional Materials City University of Hong KongHong Kong 999077China

Reducing CO_(2)to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO_(2)to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO_(2)to formate(HCOO^(-)).Turnover number(TON)for HCOO^(-)up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole(BIH)as sacrificial reductant in a CO_(2)-saturated NMP/TEA(v/v,3:1)solution under visible light *** potential electrolysis at-1.41 V(***/Ag Cl)in the presence of 12 mM Et_(3)NHBF_(4)also produced HCOO^(-)with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO_(2)reduction.

关键词： photocatalysis noble metal-free CO_(2)reduction formate cobalt hydride

Treatment of Lung Cancer with Orally Administered Chinese Herbal Medicine: An Evidence Map between 1970–2020

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Chinese Journal of Integrative Medicine 2022年第10期28卷 930-938页

作者： gui yue-rong ZHANG Ying WANG Xue-qian FAN Bing-jie LI Jing-lei ZHANG Lan-xin FAN Fen CAO Kang-di ZHANG Xiao-gang HOU Wei Department of Oncology Guang'anmen HospitalChina Academy of Chinese Medical SciencesBeijing(100053)China Cancer Project Team of China Center for Evidence-Based Traditional Chinese Medicine Beijing(100053)China

Objective: Through showing the full picture of double-arm controlled clinical research and systematic review evidence in the field of orally administrated Chinese herbal medicine(CHM) for treatment of lung cancer, to provide a reference for future clinical research and to indicate a direction for future systematic reviews. Methods: A comprehensive search of clinical controlled studies was performed regarding orally administered CHM treatment for lung cancer published from January 1970 to September 2020. The language was restricted to Chinese and English. Relevant data were extracted, the quality of systematic reviews was evaluated, and the research evidence was visually displayed. Results: Randomized controlled trials were the most common type of research design. The research sample sizes were typically small. Oral CHM showed certain curative advantages in treating lung cancer. The key stages in oral CHM intervention for lung cancer are chemotherapy, radiotherapy, and late palliative treatment. The advantageous outcomes of oral CHM treatment of lung cancer are the short-term efficacy, quality of life, and adverse reactions. The perioperative stage, overall survival, pharmacoeconomic evaluation, and Chinese medicine decoctions are weak research areas. Conclusions: CHM has staged and therapeutic advantages in treating lung cancer. The overall methodological quality is poor, and the level of evidence requires improvement. It is necessary to carry out large-scale, standardized, and higherquality research in the superior and weak areas of CHM treatment of lung cancer.

关键词： Chinese medicine clinical study evidence map evidence visualization lung cancer

Internal Activation Strategy in Peptide Ligations at Sterically Hindered Sites

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Internal Activation Strategy in Peptide Ligations at Sterica...

An extremely promiscuous terpenoid synthase from the Lamiaceae plant Colquhounia coccinea var. mollis catalyzes the formation of sester-/di-/sesqui-/mono-terpenoids

第十届全国化学生物学学术会议

作者： yue gui Yinglu Wang Suwei Dong State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University

Peptidyl thioesters have been widely used in the practice of large peptide synthesis as the requisite starting material of native chemical ligation（NCL）.[1] However, it is still a critical issue that the preparation of thioesters must be strictly controlled in order to maintain the stereocenter of the C-terminal amino acid residues. Due to the intrinsic epimerization-free property of proline under typical coupling conditions, cultivate the reactivity of prolyl thioesters in NCL has been an attractive strategy to circumvent possible epimerization at the ligation sites.[2,3] Here we present a mild and efficient internal activation strategy of peptidyl prolyl thioesters in NCL without using any thiol-based additives, where the reactivity of prolyl thioesters has been significantly improved via the formation of a bicyclic lactone-type intermediate.[4] The mechanistic investigation and utility of this method will also be disclosed.

关键词： Internal activation Native chemical ligation Proline

来源： cnki会议 cnki会议评论

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Plant Communications 2021年第5期2卷 106-119页

作者： De-Sen Li Juan Hua Shi-Hong Luo Yan-Chun Liu yue-gui Chen Yi Ling Kai Guo Yan Liu Sheng-Hong Li State Key Laboratory of Phytochemistry and Plant Resources in West China and Yunnan Key Laboratory of Natural Medicinal Chemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650201P.R.China State Key Laboratory of Southwestern Chinese Medicine Resources and Innovative Institute of Chinese Medicine and Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 611137P.R.China College of Bioscience and Biotechnology Shenyang Agricultural UniversityShengyang 110866P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Terpenoids are the largest class of natural products with complex structures and extensive bioactivities;their scaffolds are generated by diverse terpenoid synthases(TPSs)from a limited number of isoprenoid diphosphate *** TPSs play important roles in the evolution of terpenoid chemodiversity,but they remain largely ***,an extremely promiscuous terpenoid synthase(CcTPS1)of the TPS-b subfamily was cloned and functionally characterized from a leaf-specific transcriptome of the Lamiaceae plant Colquhounia coccinea ***1 is the first sester-/di-/sesqui-/mono-TPS identified from the plant kingdom,accepting C_(25)/C_(20)/C_(15)/C_(10) diphosphate substrates to generate a panel of sester-/di-/sesqui-/*** Escherichia coli expressing CcTPS1 produced three previously unreported terpenoids(two sesterterpenoids and a diterpenoid)with rare cyclohexanecontaining skeletons,along with four sesquiterpenoids and one *** structures were elucidated by extensive nuclear magnetic resonance *** benthamiana transiently expressing CcTPS1 also produced the diterpenoid and sesquiterpenoids,demonstrating the enzyme’s promiscuity in *** highly leaf-specific expression pattern combined with detectable terpenoid products in leaves of *** *** and *** expressing CcTPS1 suggested that CcTPS1 was mainly responsible for diterpenoid and sesquiterpenoid biosynthesis in ***1 expression and the terpenoid products could be induced by methyl jasmonate,suggesting their possible role in plant–environment ***1 was localized to the cytosol and may differ from mono-TPSs in subcellular compartmentalization and substrate *** findings will greatly aid our understanding of plant TPS evolution and terpenoid chemodiversity;they also highlight the enormous potential of transcriptome mining and heterologous expression for the exploration of unique enzym

关键词： terpenoid diversity terpenoid synthase promiscuous enzyme sester-/di-/sesqui-/mono-terpenoids Colquhounia coccinea var.mollis