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Upcycling of monomers derived from waste polyester plastics via electrocatalysis
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作者 Haoye Wang Richard Lee Smith Jr Xinhua Qi 《Journal of Energy Chemistry》 2025年第2期535-561,I0011,共28页
Electrocatalysis offers efficient and targeted conversion of monomers derived from waste polyester plastics to chemical products under ambient temperature and pressure conditions.This review provides analysis of resea... Electrocatalysis offers efficient and targeted conversion of monomers derived from waste polyester plastics to chemical products under ambient temperature and pressure conditions.This review provides analysis of research on electrochemical upgrading of monomers derived from waste polyester plastics published from2021 to present.Factors for assessing upgrading of waste polyester plastics include alkaline hydrolysis pretreatment,indices of electrochemical reaction process(activity,stability,and techno-economic a nalysis),separation,and product recovery.Types of depolymerization monomers and their value-added products are summarized along with electrocatalytic mechanisms and reaction pathways.Notably,cathode coupled reactions offer significant value for anodic waste plastic oxidation during electrolysis processes.Development of bifunctional electrocatalysts can reduce the cost of coupled systems and complexity of the electrolyzer.Upgrading and recycling of waste plastic monomers using electrocatalytic technology should undergo downstream processing to form high-value products containing C-N and C-S derived functional groups obtained from depolymerized monomers,Electrochemical conversion and upgrading of monomers derived from waste polyester plastics can contribute to industrialization and global economies and help to realize environmental sustainability. 展开更多
关键词 Waste plastics monomer ELECTROCATALYSIS Value-added products Upgrade recycling Coupling reaction
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Chinese medicine monomers for hepatocellular carcinoma: New ideas related to autophagy
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作者 Shi-Hao Zheng Tian-Yu Xue +2 位作者 Qiu-Yue Wang Yong-An Ye Peng Zhang 《World Journal of Gastroenterology》 2025年第26期1-21,共21页
Hepatocellular carcinoma(HCC)represents the most prevalent form of primary liver cancer,characterized by high mortality rates,frequent recurrence and metastasis,poor clinical prognosis,and a complex pathogenesis with ... Hepatocellular carcinoma(HCC)represents the most prevalent form of primary liver cancer,characterized by high mortality rates,frequent recurrence and metastasis,poor clinical prognosis,and a complex pathogenesis with limited therapeutic options.Autophagy plays a pivotal role in the immune response and functions as a lysosome-mediated degradation mechanism essential for recycling cellular components and eliminating aggregated proteins,damaged organelles,and invasive pathogens,thereby maintaining cellular function and dynamic homeostasis.Additionally,autophagy regulates several critical proteins and signaling pathways,including mammalian target of the rapamycin(mTOR),Beclin-1,the phosphatidylinositol 3-kinase/protein kinase B/mTOR signaling pathway,the Hippo/yes-associated protein signaling pathway,and the Janus kinase/signal transducer of activation signaling pathway.This regulatory capa-city of autophagy can potentially prevent or delay the progression of HCC.Nowadays,many studies have shown that different types of herbal monomers such as the more common quercetin,baicalein,berberine and emodin can further regulate autophagy and exert preventive and therapeutic effects on HCC through the modulation of mTOR and other related signaling pathways and so on.In this paper,we examine the mechanisms of autophagy,key proteins and signaling pathways involved,and the modulation of autophagy by Chinese medicine monomers in the prevention and treatment of HCC.This review aims to provide valuable insights for the development of Chinese medicine strategies against HCC and to inform the rational use of these therapies in clinical practice. 展开更多
关键词 Autophagy regulation Chinese medicine monomer Hepatocellular carcinoma Signaling pathway IMMUNOLOGY PHARMACOLOGY
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The biological roles of exosome-encapsulated traditional Chinese medicine monomers in neuronal disorders
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作者 Chen Pang Jie Zhang +2 位作者 Yujin Gu Qili Zhang Yanfang Zhao 《Journal of Pharmaceutical Analysis》 2025年第5期883-900,共18页
A traditional Chinese medicine(TCM)monomer is a bioactive compound extracted from Chinese herbal medicines possessing determined biological activity and pharmacological effects,and has gained much attention for treati... A traditional Chinese medicine(TCM)monomer is a bioactive compound extracted from Chinese herbal medicines possessing determined biological activity and pharmacological effects,and has gained much attention for treating neuronal diseases.However,the application of TCM monomers is limited by their low solubility and poor ability to cross the blood-brain barrier(BBB).Exosomes are small extracellular vesicles(EVs)ranging in size from 30 to 150 nm in diameter and can be used as drug delivery carriers that directly target cells or tissues with unique advantages,including low toxicity,low immunogenicity,high stability in blood,and the ability to cross the BBB.This review discusses the biogenesis,components,stability,surface modification,isolation technology,advantages,and disadvantages of exosomes as drug carriers and compares exosomes and other similar drug delivery systems.Furthermore,exosome-encapsulated TCM monomers exert neuroprotective roles,such as anti-inflammation,anti-apoptosis,anti-mitophagy,and anti-oxidation,in various neuronal diseases,including Alzheimer's disease(AD),Parkinson's disease(PD),multiple sclerosis(MS),and cerebral ischemia and reperfusion(CI/R)injury,as well as anti-drug resistance,anti-tumorigenesis,anti-angiogenesis,and promotion of apoptosis in brain tumors,providing more inspiration to promote the development of an exosome-based delivery tool in targeted therapy for neuronal diseases. 展开更多
关键词 Traditional Chinese medicine monomer EXOSOME Drug delivery Neuronal disease
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Groups 3 and 4 single-site catalysts for olefin-polar monomer copolymerization
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作者 Chengkai Li Guoqiang Fan +2 位作者 Gang Zheng Rong Gao Li Liu 《Chinese Chemical Letters》 2025年第9期34-45,共12页
Introducing functional polar groups into polyolefins can significantly improve the material properties,but there are still challenges in achieving this goal,with the core difficulty being that polar groups are prone t... Introducing functional polar groups into polyolefins can significantly improve the material properties,but there are still challenges in achieving this goal,with the core difficulty being that polar groups are prone to interact with metal active species,affecting the efficiency of the copolymerization.With the rapid advancement in catalyst,a variety of copolymerization strategies are developed aimed at producing more versatile polyolefin materials.Although early transition metal catalysts play an indispensable role in the traditional polyolefin industry,their inherent strong oxophilicity becomes a significant constraint in copolymerization involving polar olefins,limiting their application scope.This review summarizes the progress made in recent years in the efficient copolymerization of non-polar olefins with polar comonomers catalyzed by groups 3 and 4 single-site catalysts.We classify the catalysts into four categories,Sc-,Ti-,Zr-,Hf-,based on the type of metal centers,and provide insights into the influence of catalyst structures and the type of comonomers on the copolymerization behavior.The introduction of polar monomers fundamentally improves the comprehensive performance of the products,greatly broadens the application scope of polyolefin materials,and meets the growing market demand for multifunctional and high-performance materials. 展开更多
关键词 Single-site catalysts Groups 3 and 4 metal Polar monomers COPOLYMERIZATION Physical properties
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Different fluorinated monomers formed poly(phenanthrene-co-pterphenyl piperidinium)anion exchange membranes for fuel cells
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作者 Yingjie Liu Xibin Yue +5 位作者 Yongqi Hu Hui Peng Guoliang Zhang Aimei Zhu Qiugen Zhang Qinglin Liu 《Journal of Energy Chemistry》 2025年第6期395-406,I0009,共13页
Improving the comprehensive performance of anion exchange membranes(AEMs)has a decisive impact on the wide application of anion exchange membrane fuel cells(AEMFCs).Herein,we prepared a series of new poly(phenanthrene... Improving the comprehensive performance of anion exchange membranes(AEMs)has a decisive impact on the wide application of anion exchange membrane fuel cells(AEMFCs).Herein,we prepared a series of new poly(phenanthrene-co-p-terphenyl piperidinium)(PPTP3F_(x)-DIL)AEMs with different fluorinated monomers for high performance AEMFCs.The polymerization of fluorinated monomers with other aryl monomers can effectively promote the separation of microphase in the membrane.It also has a high OH-conductivity at a low swelling.The membrane(PPTP3F_(4)-DIL)prepared by polycondensation of 2,2,2-trifluoro-1-(p-tolyl)ethan 1-one monomer achieves a high conductivity of 168.5 mS cm^(-1)at 80℃.At the same time,the water uptake is 40.0%and the swelling ratio is 12.1%.In addition,these membranes also have good mechanical properties and alkaline stability.After 1440 h of treatment in a NaOH(2 M)solution at 80℃,PPTP3F_(x)-DIL still maintains excellent tensile strength(>30.3 MPa)and elongation at break(>43.4%),and the conductivity retention of the PPTP3F_(1)-DIL membrane is 90.3%.The PPTP3F_(4)-DIL-based single cell exhibits a high peak power density(918.1 mW cm^(-2))and excellent durability(100 h)at 80℃.Therefore,these PPTP3F_(x)-DIL membranes have a wide range of applications in AEMFCs. 展开更多
关键词 Poly(phenanthrene-co-p-terphenyl piperidinium)AEMs Different fluorinated monomers Separation of microphase Swelling
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Antifungal Effect of Streptomyces 702 Antifungal Monomer Component DZP8 on Rhizoctonia solani and Magnaporthe grisea 被引量:1
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作者 芦慧 涂晓嵘 +2 位作者 徐佳 冯华根 涂国全 《Agricultural Science & Technology》 CAS 2012年第11期2370-2374,2378,共6页
The aim of this study was to investigate the in vitro antifungal effects of antifungal monomer component DZP8 isolated from Streptomyces 702 on the mycelium growth, sclerotium formation and germination of Rhizoctonia ... The aim of this study was to investigate the in vitro antifungal effects of antifungal monomer component DZP8 isolated from Streptomyces 702 on the mycelium growth, sclerotium formation and germination of Rhizoctonia solani and on the mycelium growth, conidial formation, germination, appressorium formation of Magnaporthe grisea. The results showed that the antifungal monomer component DZP8 has strong antifungal effect on both the R. solani and M. grisea. The EC50 and EC90 of DZP8 were 1.81 and 3.35 μg/ml on Ft. solani respectively, and 37.01 and 136.21 μg/ml on M. grisea respectively. Under the treatment of 48.01 μg/ml DZP8, the sclerotium formation rate of R. solani was just 39.21%, the formation time delayed by 216 h and the dry weight decreased by 81.37% in comparison the con- trol; and 33.51 μg/ml DZP8 significantly inhibited the sclerotium germination. In the presence of 160.08 μg/ml DZP8, the sporulation of M. grisea was just 9.29% of control sample; 20.14 μg/ml DZP8 inhibited the conidial germination suppression rate by 95.16%, and the appressorium formation by 100%. 展开更多
关键词 Streptomyces 702 monomer component DZP8 Rhizoctonia solani Mag-naporthe grisea Antifungal effect
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Lipase-catalyzed Regioselective Synthesis of Vinyl Ester Derivatives of Thiamphenicol: Novel Thiamphenicol Monomers for Preparation of Macromolecular Antibiotic
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作者 YuZhenSHI ZhiChunCHEN +2 位作者 NaWANG QiWU XianFuLIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第1期45-48,共4页
Three polymerizable vinyl thiamphenicol esters with different acyl donor carbon chain length (C4, C6, C10) were regioselectivly synthesized by Lipozyme? (immobilized from mucor miehei) in acetone at 50 oC for 12 h t... Three polymerizable vinyl thiamphenicol esters with different acyl donor carbon chain length (C4, C6, C10) were regioselectivly synthesized by Lipozyme? (immobilized from mucor miehei) in acetone at 50 oC for 12 h to give 73%, 81%, 63% yield, respectively. The products were valuable monomers for preparation of macromolecular antibiotic. 展开更多
关键词 THIAMPHENICOL vinyl ester TRANSESTERIFICATION regioselectivity monomer.
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DEPENDENCE OF THE DISTRIBUTION OF ACTIVE CENTERS ON MONOMER IN SUPPORTED ZIEGLER-NATTA CATALYSTS
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作者 范志强 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第5期605-610,共6页
Distribution of active centers(ACD)of ethylene or 1-hexene homopolymerization and ethylene-1-hexene copolymerization with a MgCl_2/TiCl_4 type Z-N catalyst were studied by deconvolution of the polymer molecular weight... Distribution of active centers(ACD)of ethylene or 1-hexene homopolymerization and ethylene-1-hexene copolymerization with a MgCl_2/TiCl_4 type Z-N catalyst were studied by deconvolution of the polymer molecular weight distribution into multiple Flory components.Each Flory component is thought to be formed by a certain type of active center. ACD of ethylene-1-hexene copolymer with very low 1-hexene incorporation was compared with that of ethylene homopolymer to see the effect of introducingα-olefin on ethyle... 展开更多
关键词 Supported Ziegler-Natta catalyst Active center distribution monomer.
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The prognostic impact of traditional Chinese medicine monomers on tumor-associated macrophages in non-small cell lung cancer 被引量:17
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作者 WAN Liang-Qin TAN Yan +1 位作者 JIANG Miao HUA Qian 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2019年第10期729-737,共9页
Non-small cell lung cancer(NSCLC) accounts for 80%-85% of all lung malignancies and good diagnosis and prognosis of NSCLC are critical to the increase of its survival rate. Tumor-associated macrophages(TAM) abundantly... Non-small cell lung cancer(NSCLC) accounts for 80%-85% of all lung malignancies and good diagnosis and prognosis of NSCLC are critical to the increase of its survival rate. Tumor-associated macrophages(TAM) abundantly present in numerous cancer types, and the role of TAMs in tumor biology and their prognostic value in cancer become major topics of interest. After various stimulations in the tumor microenvironment, TAMs develop into a M1(tumor-inhibitory) phenotype or M2(tumor-promoting) phenotype. Recent studies show that traditional Chinese medicine(TCM) monomers have markedly inhibitory actions for NSCLC through M1/M2 modulation. Due to the TCM monomers mainly covered five categories, i.e. terpenoids, flavonoids, polysaccharides, natural polyphenols, and alkaloids. Thus, we will discuss the regulation of TCM monomers on TAM involve in these five parts in this review. In addition, the potential role of TAMs as therapeutic targets will be discussed. 展开更多
关键词 Lung cancer Tumor MICROENVIRONMENT TUMOR-ASSOCIATED MACROPHAGES Traditional Chinese medicine (TCM) monomer Immunotherapy
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The Effect of Vineyard Cover Crop on Main Monomeric Phenols of Grape Berry and Wine in Vitis viniferal L. cv. Cabernet Sauvignon 被引量:13
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作者 XI Zhu-mei ZHANG Zhen-wen CHENG Yu-feng LI Hua 《Agricultural Sciences in China》 CAS CSCD 2010年第3期440-448,共9页
This study was conducted to determine the effect of cover crop inter-row in vineyard on main mono-phenol content of grape berry and wine. Three such cover crops, two perennial legumes (white clover and alfalfa) and ... This study was conducted to determine the effect of cover crop inter-row in vineyard on main mono-phenol content of grape berry and wine. Three such cover crops, two perennial legumes (white clover and alfalfa) and a perennial gramineous grass (tall fescue) were sown in vineyard. The main phenolic compounds of mature grape berry and wines vinified under the same conditions were extracted with ethyl acetate and diethyl ether and analyzed by high- performance liquid chromatography (HPLC) by comparing to soil tillage. A total of ten phenolic compounds were identified and quantified in the different grape berry and wines, including nonflavonoids (hydroxybenzoic and hydroxycinnamic acids) and flavonoids (flavanols and flavonols). The concentration of flavonoid compounds (409.43 to 538.63 mg kg^-1 and 56.16 to 81.30 mg L^-1) was higher than nonflavonoids (76.91 to 98.85 mg kg^-1 and 30.65 to 41.22 mg L^-1) for Cabernet Sauvignon grape and wine under different treatments, respectively. In the flavonoid phenolics, Catechin was the most abundant in the different grapes and wines, accounting for 74.94 to 79.70% and 48.60 to 50.62% of total nonanthocyanin phenolics quantified, respectively. Compared to soil tillage, the sward treatments showed a higher content of main mono-phenol and total nonanthocyanin phenolics in grapes and wines. There were significant differences between two cover crop treatments (tall fescue and white clover) and soil tillage for the content of benzoic acid, salicylic acid, caffeic acid, catechin, and total phenolics in the grape berry (P 〈 0.05 or P〈0.01). The wine from tall fescue cover crop had the highest gallic acid, caffeic acid and catechin. Cover crop system increased the total nonanthocyanin phenolics of grapes and wines in order of the four treatments: tall fescue, white clover, alfalfa, and soil tillage (control). Cover crop in vineyard increased total phenols of grape berry and wine, and thus improved the quality of wine evidently. 展开更多
关键词 VINEYARD cover crops inter-row Cabernet Sauvignon grape berry WINE monomeric phenols
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Study progress in therapeutic effects of traditional Chinese medicine monomer in severe acute pancreatitis 被引量:26
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作者 ZHANG Xi-ping LIU Da-ren SHI Yan 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第2期147-152,共6页
Severe acute pancreatitis (SAP) is a common acute abdomen clinical problem characterized by high mortality, mul-tiple complications, complicated pathogenesis and difficult treatment. Recent studies found traditional C... Severe acute pancreatitis (SAP) is a common acute abdomen clinical problem characterized by high mortality, mul-tiple complications, complicated pathogenesis and difficult treatment. Recent studies found traditional Chinese medicine (TCM) monomers have markedly good effect for treating SAP. Many TCM monomers can inhibit pancreatin, resist inflammation, im-prove microcirculation and immunoloregulation, etc. to block the pathological progress of SAP in multiple ways, reduce com-plications and lower mortality with rapid effects. It is significant for enhancing SAP treatment to deeply understand the current situation in TCM monomers for treating SAP and take precious references therein. This article summarizes the treating effects and mechanisms of TCM monomers for SAP in recent years. 展开更多
关键词 Severe acute pancreatitis TREATMENT Traditional Chinese medicine (TCM) monomer
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Vinyl chloride monomer production catalysed by gold: A review 被引量:8
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作者 Catherine J.Davies Peter J.Miedziak +1 位作者 Gemma L.Brett Graham J.Hutchings 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第10期1600-1607,共8页
In this review we discuss the history of research into the use of gold for the acetylene hydrochlorin‐ation reaction, and describe the recent developments which have led to its commercialisation. We discuss the use o... In this review we discuss the history of research into the use of gold for the acetylene hydrochlorin‐ation reaction, and describe the recent developments which have led to its commercialisation. We discuss the use of different precursors and the addition to gold of a secondary metal as methods which attempt to improve these catalysts, and consider the nature of the active gold species. The vast majority of poly vinyl chloride (PVC) produced globally still uses a mercuric chloride as a cata‐lyst, despite the environmental problems associated with it. Due to the agreement by the Chinese government to remove mercury usage in the PVC industry over the course of the next few years there is an obvious need to find a replacement catalyst;the potential use of gold for this process has been well known for several decades and to date gold seems to be the best candidate for this, pri‐marily due to its superior selectivity when compared to other metals. 展开更多
关键词 GOLD ACETYLENE HYDROCHLORINATION Vinyl chloride monomer Poly vinyl chloride CATALYSIS
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Advances in anti-tumor effects and mechanisms of Pulsatilla Chinensis saponins and its monomers 被引量:8
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作者 Huihui Song Zhuo Xiang +3 位作者 Shuyi Xue Qing Miao Liyan Zhao Mingchun Li 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2021年第5期381-392,共12页
As a traditional Chinese herbal medicine, Pulsatilla Chinensis(P. Chinensis) is widely used in the clinical practice of traditional Chinese medicine(TCM). Recently, medical research has found that the natural product ... As a traditional Chinese herbal medicine, Pulsatilla Chinensis(P. Chinensis) is widely used in the clinical practice of traditional Chinese medicine(TCM). Recently, medical research has found that the natural product P. Chinensis saponins and their monomeric compounds extracted from P. Chinensis have a variety of biological activities, especially the triterpenoid saponins, which have significant and broad-spectrum anti-tumor effects. Moreover, its anti-tumor molecular mechanisms include inhibition of the growth and proliferation of tumor cells, repression of the migration, invasion, and metastasis, prevention of tumor cell cycle, regulation of cancer cell energy metabolism, anti-tumor angiogenesis, induction of cancer cell differentiation, apoptosis and autophagy, reversing cancer cell resistance, regulation a variety of related signaling pathways, and improvement of the inflammatory microenvironment of tumor cells. In the present work, we reviewed the related anticancer mechanisms of P. Chinensis saponins and their monomers in different tumors, aiming to provide a theoretical basis for the development and clinical application of new anti-tumor drugs of P. Chinensis saponins and their monomeric compounds. 展开更多
关键词 Pulsatilla Chinensis Pulsatilla Chinensis saponins monomer Anti-tumor effect Molecular mechanism
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Antiviral Activity of the Effective Monomers from Folium Isatidis Against Influenza Virus in Vivo 被引量:9
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作者 Zhao LIU Zhan-qiu YANG Hong XIAO 《Virologica Sinica》 SCIE CAS CSCD 2010年第6期445-451,共7页
In order to evaluate the anti-influenza virus activity of the effective monomer from Folium Isatidis (FI) in vivo,we established mice model with viral pneumonia and divided them into 3 different dose groups,then obser... In order to evaluate the anti-influenza virus activity of the effective monomer from Folium Isatidis (FI) in vivo,we established mice model with viral pneumonia and divided them into 3 different dose groups,then observed their lung indexes,pulmonary pathological changes,pulmonary virus hemagglitination titers,living time and death rates.The results showed that the monomer could reduce the pulmonary index from 2.64 to 1.93,1.63 and 1.40 (P<0.01) and decrease the hemagglitination titer from 1.15 to 0.84,0.70 and 0.59 (P<0.01).In addition,different groups of FI could significantly lessen the mortality rate from 100% to 30%,25% and 15%,and prolong the living time from 5.1d to 6.5d,8.4d and 8.9d respectively(P<0.01).The high dose (75 mg/kg/d) has the similar effect with 100 mg/kg/d dose of virazole(P>0.05),and more effective than 200 mg/kg/d dose of antiviral liquor (P<0.05). 展开更多
关键词 Folium Isatidis monomerS Influenza virus Antiviral activity In vivo
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Effect of cationic monomer on properties of fluorinated acrylate latex 被引量:6
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作者 Li Jun Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第6期736-740,共5页
Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering ... Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering detector and contact angle meter. Influences of amount of DMDAAC on the properties of resultant latex and its film were investigated in detail. Results show that the particle size of the latex has the minimum value knd the zeta potential of the latex is increased when the amount of DMDAAC is increased. In addition, the particle size of the latex is unimodal distribution when the amount of DMDAAC is not more than 2.5%. However, the particle size of the latex is bimodal distribution when the amount of DMDAAC is more than 2.5%. The contact angle is varied slightly with the increase of amount of DMDAAC when it is not more than 2.5%. Nevertheless, the contact angle is decreased with the increase of the amount of DMDAAC when it is more than 2.5%. 展开更多
关键词 Cationic fluorinated acrylate latex Cationic monomer Semi-continuous emulsion polymerization PROPERTIES
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Ethylene Polymerization and Copolymerization with Polar Monomers by Benzothiophene-bridged BPMO-Pd Catalysts 被引量:6
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作者 Hong-Liang Mu Jun-Hao Ye +2 位作者 Guang-Lin Zhou Kang-Kang Li Zhong-Bao Jian 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2020年第6期579-586,共8页
A series of new bisphosphine-monoxide(BPMO)ligands based on benzothiophene backbone and the corresponding palladium complexes{k2-P(O)(Ph)2-3-PR1R2-C8H4S}PdMeCl{2a:R1=R2=Ph;2b:R1=R2=2-0Me-Ph;2c:R1=R2=2-CF3-Ph;2d:Rl=Ph,... A series of new bisphosphine-monoxide(BPMO)ligands based on benzothiophene backbone and the corresponding palladium complexes{k2-P(O)(Ph)2-3-PR1R2-C8H4S}PdMeCl{2a:R1=R2=Ph;2b:R1=R2=2-0Me-Ph;2c:R1=R2=2-CF3-Ph;2d:Rl=Ph,R2=2-(2',6'-(OMe)2C6Hz)-C6H4}were synthesized and fully characterized by1H-,13C-,31P-,and 2D-NMR spectroscopy and single-crystal X-ray dfraction.In the presence of Na+B[3,5-(CF3)2C6H3]4(NaBArF),these complexes showed very high activities(up to 2.0 x 10’g-mol-1.h-)for ethylene polymerization.More significantly,these catalysts enabled the copolymerization of ethylene with a broad scope of commercially available polar comonomers such as acrylates,acrylic acid,acrylonitrile,vinyltrialkoxysilane,allyl acetate,and long-chain 6-chloro-1-hexene to give functionalized polyethylene with reasonable catalytic activities(up to 105 g-mol-l.h-)and incorporations(up to 5.3 mol96).This contribution suggests that,besides the modulation of conventionally steric and electronic factors,the connectivity(at dfferent linking positions)of BPMO(P,O)donors to the heteroaryl backbone also greatly infuences the catalyst properties in terms of catalytic activity,polymer branching content,comonomer scope,and comonomer incorporation. 展开更多
关键词 OLEFIN polymerization BISPHOSPHINE MONOXIDE Plladium Polar monomerS Heteroaryl backbone
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Evaluation in vinyl chloride monomer-exposed workers and the relationship between liver lesions and gene polymorphisms of metabolic enzymes 被引量:6
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作者 Shou-Min Zhu Xue-Feng Ren Jun-Xiang Wan Zhao-Lin Xia 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第37期5821-5827,共7页
AIM: To analyze occupational health hazards exposure to doses lower than the Chinese occupational health standard in a selected VC polymerization plant in China, and also to elucidate the relationship between genetic... AIM: To analyze occupational health hazards exposure to doses lower than the Chinese occupational health standard in a selected VC polymerization plant in China, and also to elucidate the relationship between genetic polymorphisms and genetic susceptibility on liver lesions of workers exposed to vinyl chloride monomer (VCM). METHODS: In order to explore the mechanism of VCM- related health effects, we used a case-control design to investigate the association between the genetic polymorphisms of metabolic enzymes and liver lesions in workers occupationally exposed to VCM. Genotypes of CYP2E1, GSTT1, GSTM1, ALDH2 and ADH2 were identified using PCR and PCR-RFLP. RESULTS: Even when the concentration of VCM was lower than the current Chinese occupational health standard, neurasthenia, pharyngeal irritation, liver ultrasonography abnormalities and hemoglobin disorders were significantly higher in exposure subjects compared to non-exposure subjects, and the relative risks (RRand 95% C1) were 1.74 (1.06-2.85), 1.97 (1.56-2.48), 10.69 (4.38-26.12), and 2.07 (1.20-3.57). CYP2E1 c1c2/c2c2 genotype was significantly associated with liver damages (OR 3.29, 95% CI 1.51-7.20, P〈0.01). CONCLUSION: The incidences of neurasthenia and liver ultrasonography abnormalities significantly increase when the cumulative exposure dose increases. The genotypes of metabolic enzymes (CYP2E1 c1c2/c2c2, null GSTT1 and ADH2 1-1) play important roles in VCM metabolism. Polymorphisms of CYP 2E1, GSTT1 and ADH2 may be a major reason of genetic susceptibility in VCM-induced hepatic damage. 展开更多
关键词 Vinyl chloride monomer Hepatic lesions Cytochrome p450 2E1 Glutathione S-transferase Aldehyde dehydrogenase-2
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Controllably Growing Topologies in One-shot RAFT Polymerization via Macro-latent Monomer Strategy 被引量:3
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作者 Liu-Qiao Zhang Yang Gao +4 位作者 Zhi-Hao Huang Wei Zhang Nian-Chen Zhou Zheng-Biao Zhang Xiu-Lin Zhu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2021年第1期60-69,I0006,共11页
The controlled and efficient synthesis of polymers with tailored topologies is challenging but important for exploring structure/property research. Herein, we proposed a concept of macro-latent monomer to achieve the ... The controlled and efficient synthesis of polymers with tailored topologies is challenging but important for exploring structure/property research. Herein, we proposed a concept of macro-latent monomer to achieve the controlled growth of polymer topologies.The macro-latent monomer was installed by a dynamic furan/maleimide covalent bond at the chain terminal. One-shot reversible additionfragmentation chain transfer(RAFT) polymerization of styrene and the macro-latent monomer created controlled growth of polymer topologies.Low temperature such as 40 ℃ could not activate the macro-latent monomer and thus the polymerization created the homo-polystyrene. By contrast, high temperature of ~110 ℃ activated the macro-latent monomer, and a maleimide-terminated macro-monomer was released via the retro-Diels Alder reaction. This macro-monomer immediately joined the cross polymerization with styrene and thus produced the side chains. By delicately manipulating the polymerization temperature, the predetermined placement of the macro-latent monomer-derived polymeric sidechains created controllably growing topologies, including star-, π-shaped, and density-variable grafting copolymers. This work paved a new way for creating on-demand topologies and would greatly enrich the topology synthesis. 展开更多
关键词 Latent monomer Diels-Alder reaction MALEIMIDE STYRENE TOPOLOGIES
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MXene-assisted polymer coating from aqueous monomer solution towards dendrite-free zinc anodes 被引量:3
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作者 Ning Wang Zhitan Wu +7 位作者 Yu Long Derong Chen Chuannan Geng Xiaochen Liu Daliang Han Jing Zhang Ying Tao Quan-Hong Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第10期277-284,I0006,共9页
Coating polymer on the surface is an effective way to realize functional modification of the materials for diverse applications,which has been proved to enhance the stability of metal anodes in batteries.However,given... Coating polymer on the surface is an effective way to realize functional modification of the materials for diverse applications,which has been proved to enhance the stability of metal anodes in batteries.However,given the limited operability of coating from polymer dispersions,it is imperative to develop simple aqueous-based strategies from monomers for versatile polymer coating.Herein,a Ti_(3)C_(2)Tx MXene-assisted approach is proposed to construct polymer coating on zinc metal surfaces directly from the aqueous solution of monomers in an ice bath.By combining a doctor-blading method with spontaneous polymerization of monomers on the substrates at room temperature,a uniform,adhesive,and versatile coating layer assisted by a small amount of MXene is produced in one step.Additionally,MXene nanosheets serve as nanofillers to further enhance the mechanical strength and ionic conductivity of the polymer coating.Benefiting from good film formation and improved interfacial contact,the coated zinc anode exhibits a long cycling lifespan of over 1900 h.The assembled full cells show excellent cycling stability with a high capacity retention of 85.0%at 16 A g^(-1)over 2600 cycles.This work provides a simple and efficient way to produce polymer coatings directly from monomers,which may give new insights into design multifunctional polymer coatings for various applications. 展开更多
关键词 MXene Polymer coating monomer Zinc anode Dendrite-free
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Improving acceptor efficacy rather than energy transfer efficiency:Dominant contribution of monomers of acceptors modified on upconversion nanoparticles 被引量:3
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作者 Jie Ren Yadan Ding +4 位作者 Hancheng Zhu Zhipeng Li Xia Hong Huiying Zhao Hong Zhang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2022年第5期702-708,I0001,共8页
Upconversion nanosensitizers have been widely considered to have important applications in the treatment of major diseases such as tumors and the utilization of solar energy.Majority of the efforts so far have been fo... Upconversion nanosensitizers have been widely considered to have important applications in the treatment of major diseases such as tumors and the utilization of solar energy.Majority of the efforts so far have been focused on improving the efficiency of energy transfer(ET)between upconversion nanoparticles(UCNPs)and the anchored sensitizers with premise that high ET efficiency will lead to high acceptor efficacy.This premise is,however,proved by our current work to be invalid for commonly used load.Interaction between adjacent sensitizing molecules was found to be critical which undermines the amount of excited monomer sensitizers and thus fades the efficacy.Here NaYF_(4):Yb^(3+),Er^(3+)UCNPs and rose bengal(RB)photosensitizer molecules were used as the model energy donors and acceptors,respectively.Contrary to monotonous increase of the ET efficiency from UCNPs to RB species with increasing RB loading,acceptor efficacy characterized by the reactive oxygen species,as well as the RB fluorescence,exhibits bizarre dependence on the RB loading.The underlying mechanism was well studied by the steady-state and time-resolved spectroscopy of a series of samples.RB aggregates are believed to be responsible for the severe deviation between the ET efficiency and acceptor efficacy.The conclusion was validated by in vitro test where the photodynamic therapy with the most monomer RB in UCNPs-RB nanosensitizers kills 35.8%more cells than that with the highest RB loading.This understanding sheds light on construction of new ET based nanosystems for broad applications,such as medicine,solar energy utilization and optical storage. 展开更多
关键词 Upconversion nanoparticle Energy transfer monomer Aggregate Reactive oxygen species Rare earths
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