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Preparation and Unimolecular-Micellization Behavior of Homopolymer of Surface-Active Monomer AMC14AB
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作者 Kang-kai Liu Lei Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第5期469-475,共7页
(2-acrylamido) ethyl tetradecyl dimethylammonium bromide (AMC14AB) was polymerized in aqueous solu- tion to form the homopolymer P(AMC14AB). The physicochemical properties of P(AMC14AB) in aqueous solution wer... (2-acrylamido) ethyl tetradecyl dimethylammonium bromide (AMC14AB) was polymerized in aqueous solu- tion to form the homopolymer P(AMC14AB). The physicochemical properties of P(AMC14AB) in aqueous solution were mainly studied with fluorescent probe method, surface tension measurement and conductom- etry. The experimental results show that the aggregation morphology of P(AMC14AB) in aqueous solution is unimolecular micelle as expected. Being different from conventional multimolecular micelle systems, the unimolecular micelle system of P(AMC14AB) not only shows critical micellar concentration (CMC=0), (i.e. once added to pure water, the surface tension decreases immediately in spite how small the density is), but also the surface tension stays almost the same with the concentration increasing. That is to say, there is no mutational point on the relationship curve between surface tension and concentration. Furthermore, the unimolecular micelle system of P(AMC14AB) has no Krafft temperature, i.e. at any temperature, so long as it is dissolved in water, the unimolecular micelles will form. Besides this, for the solubilization of hydrophobic organic substances, the unimolecular micelle system of P(AMC14AB) is obviously different from the common multimolecular micelle system, having no turning point on the relationship curve between toluene solubi- lizaion amount and P(AMC14AB) concentration, and the solubilizing ability of the unimolecular-micelle system of P(AMC14AB) for hydrophobic organic substances is much higher than that of the conventional multimolecular micelle solutions of common surfactants, such as centyl trimethyl ammonium bromide. 展开更多
关键词 Surface active monomer Unimolecular micelle Zero critical micellar concentration Krafft temperature
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Research progress of TCM monomer in treating diabetic kidney disease based on inflammatory mechanism
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作者 HAN Wen-long QIN Jia-ping +1 位作者 LIN Ke-xin LIU Qiang 《Journal of Hainan Medical University》 CAS 2024年第3期63-68,共6页
With the increasing morbidity of diabetes mellitus (DM), diabetic kidney disease (DKD) has become the major reason causing chronic kidney disease (CKD) and end-stage renal disease (ESRD) over the world. However, curre... With the increasing morbidity of diabetes mellitus (DM), diabetic kidney disease (DKD) has become the major reason causing chronic kidney disease (CKD) and end-stage renal disease (ESRD) over the world. However, current treating strategy is aiming at blood glucose controlling and renin-angiotensin system (RAS) restricting which can’t effectively preventing the development of DKD. Recent research indicating that low level of inflammatory and activation of immune system play a significant role in occurrence and progression of DKD. Understanding of inflammatory cascade and its mechanism is conducive to discern novel target of DKD and contributing to design new treating strategy based on anti-inflammatory. For the past few years, an increasing number of evidences proved that Tradit Chin Med (TCM) could delay the progression of ESRD on the basis of inflammatory. In this review, we overview the protective effect against DKD-based renal injury of TCM monomer, offering novel ideas in drug discovery and in mechanism-related research.sd. 展开更多
关键词 Diabetic kidney disease INFLAMMATION monomer of Chinese traditional HERBS
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An Affordable and Easily Accessible Approach for Acrylonitrile Monomer Purification through a Simple Column Technique
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作者 Rawdah Whba Mohd Sukor Su’ait Azizan Ahmad 《Journal of Materials Science and Chemical Engineering》 2024年第4期18-28,共11页
This manuscript presents a dataset detailing a method for purifying monomers. Purification plays a crucial role in every chemical process, as it leads to an improvement in product quality through the removal of impuri... This manuscript presents a dataset detailing a method for purifying monomers. Purification plays a crucial role in every chemical process, as it leads to an improvement in product quality through the removal of impurities. The primary method for monomer purification, like acrylonitrile (AN), is the distillation technique. However, this technique is unsafe and hard to set up or handle. A straightforward, risk-free, low-cost method like the column technique resolves these issues. A simple column technique demonstrated the successful execution of purifying AN. Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) analyses confirmed that AN was successfully purified, with purity reaching 99.8%. FTIR spectra revealed changes in the position and intensity of the stretching vibration peaks after purification. Also, the functional groups of the inhibitor monomethyl ether of hydroquinone (MeHQ) were undetected after purification. Furthermore, after purification, NMR spectra revealed the absence of aromatic protons and carbons associated with MeHQ. In conclusion, the column technique is a successful and inexpensive way to purify AN monomers. This makes it useful for a wide range of applications, especially in polymerization reactions where MeHQ needs to be removed to prevent self-polymerization during the initiation process. 展开更多
关键词 Liquid monomers ACRYLONITRILE PURIFICATION Inhibitor Simple Column
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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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possible role of soluble fibrin monomer complex after gastroenterological surgery 被引量:3
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作者 Masatoshi Kochi Manabu Shimomura +6 位作者 Takao Hinoi Hiroyuki Egi Kazuaki Tanabe Yasuyo Ishizaki Tomohiro Adachi Hirotaka Tashiro Hideki Ohdan 《World Journal of Gastroenterology》 SCIE CAS 2017年第12期2209-2216,共8页
AIM To examine the role of soluble fibrin monomer complex(SFMC) in the prediction of hypercoagulable state after gastroenterological surgery.METHODS We collected data on the clinical risk factors and fibrin-related ma... AIM To examine the role of soluble fibrin monomer complex(SFMC) in the prediction of hypercoagulable state after gastroenterological surgery.METHODS We collected data on the clinical risk factors and fibrin-related makers from patients who underwent gastroenterological surgery at Hiroshima University Hospital between April 1, 2014 and March 31, 2015. We investigated the clinical significance of SFMC, which is known to reflect the early plasmatic activation of coagulation, in the view of these fibrin related markers.RESULTS A total of 123 patients were included in the present study. There were no patients with symptomatic VTE. Thirty-five(28%) patients received postoperative anticoagulant therapy. In the multivariate analysis, a high SFMC level on POD 1 was independently associated with D-dimer elevation on POD 7(OR = 4.31, 95%CI: 1.10-18.30, P = 0.03). The cutoff SFMC level was 3.8 μg/ml(AUC = 0.78, sensitivity, 63%, specificity, 89%). The D-dimer level on POD 7 was significantly reduced in high-SFMC patients who received anticoagulant therapy in comparison to highSFMC patients who did not.CONCLUSION The SFMC on POD 1 strongly predicted the hypercoagulable state after gastroenterological surgery than the clinical risk factors and the other fibrin related markers. 展开更多
关键词 Hypercoagulable state Gastroenterological surgery Soluble fibrin monomer complex Venous thromboembolism Anticoagulant therapy
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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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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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A novel associative latex thickener using ethoxylated behenyl methacrylate as functional monomer 被引量:2
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作者 Xiang Zheng Kong Chen Wang +1 位作者 Xu Bao Jiang Xiao Li Zhu 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第5期616-619,共4页
Alkali-soluble associative latex thickeners modified with hydrophobic long chain alkyl groups were prepared using common acrylics and varying amount of a functional monomer,ethoxylated behenyl methacrylate(BEM),throug... Alkali-soluble associative latex thickeners modified with hydrophobic long chain alkyl groups were prepared using common acrylics and varying amount of a functional monomer,ethoxylated behenyl methacrylate(BEM),through emulsion polymerization.It was found that the size of the emulsion particle became larger with addition of BEM.The light transmittance of the thickener latex sharply increased with pH varied from 6 to 7.The associative latex thickener manifested a higher viscosity when solids in the latex thickeners were kept at 0.5 wt%or higher,and the optimal amount of BEM was found to be around 2.5 wt%,or 0.16 mol%.All thickener latexes modified with BEM have better shearing resistance than the BEM-free thickener. 展开更多
关键词 Associative thickener Functional monomer Ethoxylated behenyl methacrylate VISCOSITY
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Simulation research on monomer agglomeration of nonmetallic inclusions in steel with a diffusion limited aggregation model 被引量:4
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作者 Hong Li Linxin Ning +3 位作者 Juan Wen Jiongming Zhang Yasushi Sasaki Mitsutaka Hino 《Journal of University of Science and Technology Beijing》 CSCD 2006年第2期117-120,共4页
The monomer agglomeration of nonmetallic inclusions was simulated with a diffusion limited aggregation (DLA) model of the fractal theory. The simulation study with a random two-dimensional diffusion was carried out.... The monomer agglomeration of nonmetallic inclusions was simulated with a diffusion limited aggregation (DLA) model of the fractal theory. The simulation study with a random two-dimensional diffusion was carried out. The results indicate that the DLA model can be used for the simulation of agglomeration behavior of the cluster-type inclusions. The morphology of clusters was observed with SEM and compared with the simulated agglomerates. The modelling procedure of the DLA model is applicable for the agglomeration process. The uncertainty of agglomeration process and the persuasive average agglomerative ratio was analyzed. The factors about the agglomerative ratio with the collision path distance and the size of particles or seed were discussed. The adherence of the nonmetallic inclusions on the dam, the weir and the walls of a tundish, and the absorption of inclusions by stopper or nozzle were also discussed. 展开更多
关键词 fractal theory diffusion limited aggregation (DLA) model monomer agglomeration agglomerative ratio nonmetallic inclusions
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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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HYDROPHOBICALLY ASSOCIATING POLYACRYLAMIDES MODIFIED BY A NOVEL SELF-ASSOCIATIVE CATIONIC MONOMER 被引量:2
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作者 吴飞鹏 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第2期137-145,共9页
A series of hydrophobically associating polyacrylamides modified by small amounts (〈 3 mol%) of a self- associative cationic monomer 4-(2-(acryloyloxy) ethoxy) benzyl tri-ethyl ammonium bromide (AEBA) as hydr... A series of hydrophobically associating polyacrylamides modified by small amounts (〈 3 mol%) of a self- associative cationic monomer 4-(2-(acryloyloxy) ethoxy) benzyl tri-ethyl ammonium bromide (AEBA) as hydrophobe were synthesized by radical copolymerization in aqueous solutions without external surfactants. The resulting eopolymers containing a multiblock structure exhibited a high tendency for hydrophobic association and a high thickening capacity. Solution properties and aggregation structures were investigated by viscometry and fluorescence technique. The high viscosity enhancement was found as the polymer concentration beyond a critical value c* and strongly depended on the copolymer microstructures. The number and length of hydrophobic microblocks within the copolymer backbones could be controlled by changing the AEBA concentration in copolymerization system. Addition of salt induced more hydrophobic association and viscosity enhancement. The synthesis method used was simple and environmentally friendly without any external surfactant contamination in comparison with the conventional micellar copolymerization. 展开更多
关键词 Self-associative monomer Hydrophobically associating copolymer Aggregation behavior and structure Viscosity enhancement.
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Yizhijiannao Granule and a combination of its effective monomers,icariin and Panax notoginseng saponins,inhibit early PC12 cell apoptosis induced by beta-amyloid(25-35) 被引量:3
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作者 Ting Zhang Zhanwei Zhang +2 位作者 Keli Dong Guangcheng Li Hong Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第24期1845-1850,共6页
One of our previous studies showed that Yizhijiannao Granule,a compound Chinese medicine, effectively improved the clinical symptoms of Alzheimer’s disease.In the present study,we established a model of Alzheimer’s ... One of our previous studies showed that Yizhijiannao Granule,a compound Chinese medicine, effectively improved the clinical symptoms of Alzheimer’s disease.In the present study,we established a model of Alzheimer’s disease using beta-amyloid(25-35)in PC12 cells,and treated the cells with Yizhijiannao Granule and its four monomers,i.e.,icariin,catechin,Panax notoginseng saponins,and eleutheroside E.Flow cytometry showed that Yizhijiannao Granule-containing serum, icariin,Panax notoginseng saponins,and icariin+Panax notoginseng saponins were protective against beta-amyloid(25-35)-induced injury in PC12 cells.Icariin in combination with Panax notoginseng saponins significantly inhibited early apoptosis of PC12 cells with beta-amyloid (25-35)-induced injury compared to icariin or Panax notoginseng saponins alone.The effects of icariin+Panax notoginseng saponins were similar to the effects of Yizhijiannao Granule.The findings indicate that two of the effective monomers of Yizhijiannao Granule,icariin and Panax notoginseng saponins,can synergistically inhibit early apoptosis of PC12 cells induced by beta-amyloid(25-35). 展开更多
关键词 Alzheimer’s disease ICARIIN Panax notoginseng Saponins Yizhijiannao Granule Chinese medicine monomer beta-amyloid protein PC12 cell Chinese medicine neural regeneration
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Effects of Surface-Active Elements Sulfur on Flow Patterns of Welding Pool 被引量:3
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作者 Yuzhen ZHAO, Yongping LEI and Yaowu SHI School of Materials Science and Engineering, Beijing University of Technology, Beijing 100022, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第3期408-414,共7页
A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc (GTA) welding pool with different sulfur concentrations. It has been shown that, the weld penet... A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc (GTA) welding pool with different sulfur concentrations. It has been shown that, the weld penetration increases sharply with increasing sulfur content. When sulfur content increases beyond 80 × 10-6, the increase in sulfur content does not have an appreciable difference on the welding pool size and shape, and the depth/width remains constant. Sulfur changes the temperature dependence of surface tension coefficient from a negative value to a positive value and causes significant changes on flow patterns. The increase in soluble sulfur content and the decrease at free surface temperature can extend the region of positive surface tension coefficient. As sulfur content exceeds 125×10-6, the sign of surface tension coefficient is positive. Depending upon the sulfur concentrations, three, one or two vortexes that have different positions, strength and directions may be found in the welding pool. The contrary vortexes can efficiently transfer the thermal energy from the arc, creating a deep welding pool. An optimum range of sulfur content is 20-150×10-6. 展开更多
关键词 surface-active elements SULFUR Plow patterns Depth/width
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PREPARATION AND SURFACE PROPERTIES OF ACRYLIC COPOLYMERS CONTAINING FLUORINATED MONOMERS 被引量:1
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作者 Tai-jiang Gui Hao Wei +3 位作者 Ying Zhao Xiu-lin Wang Du-jin Wang Duan-fu Xu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第6期575-578,共4页
A series of copolymers comprising butylmethacrylate, styrene, butylacrylate, hydroxypropyl acrylate and perfluoroalkyl methacrylate were synthesized by the free radical polymerization using BPO as an initiator. The su... A series of copolymers comprising butylmethacrylate, styrene, butylacrylate, hydroxypropyl acrylate and perfluoroalkyl methacrylate were synthesized by the free radical polymerization using BPO as an initiator. The surface property of the copolymer films was subsequently characterized. The contact angle measurements and energy dispersive analysis of X-ray (EDAX) show that the length and content of perfluoroalkyl side chains in the copolymers are crucial for the preparation of the film with low surface energy. At a given content of fluorinated monomers in the copolymers, the longer the perfluoroalkyl side chain, the larger the water contact angle of the copolymer films will be. On the other hand, the higher the content of fluorinated monomers, the lower the surface energy is. The water contact angle increases with the increase of the fluorinated monomer content and reaches a plateau at 3 wt% of fluorinated monomer content. 展开更多
关键词 Acrylate copolymers Fluorinated monomers Surface property Contact angle X-ray energy dispersive analysis.
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MXene-assisted polymer coating from aqueous monomer solution towards dendrite-free zinc anodes 被引量:2
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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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Measurement of Monomer Reactivity Ratios of D,L-3-Methylglycolide with Glycolide or D,L-Lactide 被引量:1
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作者 Chang Ming DONG Kun Yuan QIU +1 位作者 Zhong Wei GU Xin De FENG Department of Polymer Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 National Research Institute for Family Planning, Beijing 100081 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第9期815-818,共4页
For monomer reactivity ratios study, the copolymerization of D,L-3-methylglycolide (MG) with glycolide (GA) or D,L-lactide (LA) was carried out in bulk to a certain low conversion in the presence of stannous octoate a... For monomer reactivity ratios study, the copolymerization of D,L-3-methylglycolide (MG) with glycolide (GA) or D,L-lactide (LA) was carried out in bulk to a certain low conversion in the presence of stannous octoate at 140 degrees C. The copolymer compositions were determined by H-1 NMR spectroscopy. The monomer reactivity ratios were evaluated by Fineman-Ross method, Kelen-Tudos method and linear least-squares method. The monomer reactivity ratios of D,L-3-methylglycolide and glycolide or D,L-lactide are r(mg)= 0.73, r(ga)= 1.47; r(mg)= 1.71, r(la)= 0.92, respectively. 展开更多
关键词 D L-3-methylglycolide GLYCOLIDE D L-lactide ring-opening copolymerization monomer reactivity ratios
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New Family of Functionalized Monomers Based on Amines: A Novel Synthesis that Exploits the Nucleophilic Substitution Reaction 被引量:2
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作者 Lissette Agüero Luis G. Guerrero-Ramírez Issa Katime 《Materials Sciences and Applications》 2010年第3期103-108,共6页
Chemistry modifications are usually performed to introduce specific group that can increase properties and functionality of materials. In this study, we present the synthesis of six new functionalized monomers prepare... Chemistry modifications are usually performed to introduce specific group that can increase properties and functionality of materials. In this study, we present the synthesis of six new functionalized monomers prepared by nucleophilic substitution reactions. Reaction of aliphatic and aromatic amines with acryloyl chloride at –20&#186;C, in presence of triethylamine allowed the synthesis of the corresponding amides. Proton nuclear magnetic resonance (1H NMR) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy and ultraviolet- visible (UV-Vis) measurements confirmed the success of the synthesis with a yield over 90%. These compounds emerged as potentially attractive monomers since they can be used to obtain stimuli-sensitive polymeric materials, due to the presence of amide and pyridine groups. 展开更多
关键词 Functional monomerS FTIR NMR Polymer Design UV-VIS
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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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Recent Strategies for the Development of Biosourced-Monomers, Oligomers and Polymers-Based Materials: A Review with an Innovation and a Bigger Data Focus 被引量:3
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作者 Serge Rebouillat Fernand Pla 《Journal of Biomaterials and Nanobiotechnology》 2016年第4期167-213,共47页
After setting the ground of the quantum innovation potential of biosourced entities and outlining the inventive spectrum of adjacent technologies that can derive from those, the current review highlights, with the sup... After setting the ground of the quantum innovation potential of biosourced entities and outlining the inventive spectrum of adjacent technologies that can derive from those, the current review highlights, with the support of Bigger Data approaches, and a fairly large number of articles, more than 250 and 10,000 patents, the following. It covers an overview of biosourced chemicals and materials, mainly biomonomers, biooligomers and biopolymers;these are produced today in a way that allows reducing the fossil resources depletion and dependency, and obtaining environmentally-friendlier goods in a leaner energy consuming society. A process with a realistic productivity is underlined thanks to the implementation of recent and specifically effective processes where engineered microorganisms are capable to convert natural non-fossil goods, at industrial scale, into fuels and useful high-value chemicals in good yield. Those processes, further detailed, integrate: metabolic engineering involving 1) system biology, 2) synthetic biology and 3) evolutionary engineering. They enable acceptable production yield and productivity, meet the targeted chemical profiles, minimize the consumption of inputs, reduce the production of by-products and further diminish the overall operation costs. As generally admitted the properties of most natural occurring biopolymers (e.g., starch, poly (lactic acid), PHAs.) are often inferior to those of the polymers derived from petroleum;blends and composites, exhibiting improved properties, are now successfully produced. Specific attention is paid to these aspects. Then further evidence is provided to support the important potential and role of products deriving from the biomass in general. The need to enter into the era of Bigger Data, to grow and increase the awareness and multidimensional role and opportunity of biosourcing serves as a conclusion and future prospects. Although providing a large reference database, this review is largely initiatory, therefore not mimicking previous classic reviews but putting them in a multiplying synergistic prospective. 展开更多
关键词 Biomass Biosourced monomers Advanced Biomaterials Chemical Building Blocks Design Strategy Metabolic Engineering INNOVATION Bigger Data
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Determination of Residual Monomers in Polycarboxylate Superplasticizer Using High Performance Liquid Chromatography 被引量:1
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作者 郭丽萍 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第3期439-442,共4页
A procedure was developed for the determination of residual monomers in polycarboxylate superplasticizer (PCs) by reversed-phase high performance liquid chromatography (RP-HPLC).Four kinds of residual monomers wer... A procedure was developed for the determination of residual monomers in polycarboxylate superplasticizer (PCs) by reversed-phase high performance liquid chromatography (RP-HPLC).Four kinds of residual monomers were well separated and determined on a SinoChrom ODS-BP (C18) column with mobile phases composed of acetonitrile and phosphate buffer solution.The monomers were detected by UV detector at 205 nm and quantitatively analyzed with an external standard method.For those residual monomers,the linear response ranged from 4.0×10-6 mol·L-1 to 2.0×10-3 mol·L-1.The determination limit of acrylic acid,sodium methylallyl sulfonate and 2-Acrylamido-2-methylpropane sulfonic acid was 0.02×10-5 mol·L-1,while that of methoxy-polyethylene glycol monoacrylate was 0.1×10-5 mol·L-1.The relative standard deviation (RSD) of high concentration samples was less than 1%,while that of the low concentration samples was between 1%-4%.The standard (additional) recovery ratio was 97.4% -104.2%. 展开更多
关键词 polycarboxylate superplasticizer monomer HPLC copolymerization
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