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Synthetic polymers:A review of applications in drilling fluids 被引量:1
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作者 Shadfar Davoodi Mohammed Al-Shargabi +2 位作者 David A.Wood Valeriy S.Rukavishnikov Konstantin M.Minaev 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期475-518,共44页
With the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various complicatio... With the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various complications.Currently,reagents based on modified natural polymers(which are naturally occurring compounds)and synthetic polymers(SPs)which are polymeric compounds created industrially,are widely used to prevent emerging complications in the drilling process.However,compared to modified natural polymers,SPs form a family of high-molecular-weight compounds that are fully synthesized by undergoing chemical polymerization reactions.SPs provide substantial flexibility in their design.Moreover,their size and chemical composition can be adjusted to provide properties for nearly all the functional objectives of drilling fluids.They can be classified based on chemical ingredients,type of reaction,and their responses to heating.However,some of SPs,due to their structural characteristics,have a high cost,a poor temperature and salt resistance in drilling fluids,and degradation begins when the temperature reaches 130℃.These drawbacks prevent SP use in some medium and deep wells.Thus,this review addresses the historical development,the characteristics,manufacturing methods,classification,and the applications of SPs in drilling fluids.The contributions of SPs as additives to drilling fluids to enhance rheology,filtrate generation,carrying of cuttings,fluid lubricity,and clay/shale stability are explained in detail.The mechanisms,impacts,and advances achieved when SPs are added to drilling fluids are also described.The typical challenges encountered by SPs when deployed in drilling fluids and their advantages and drawbacks are also discussed.Economic issues also impact the applications of SPs in drilling fluids.Consequently,the cost of the most relevant SPs,and the monomers used in their synthesis,are assessed.Environmental impacts of SPs when deployed in drilling fluids,and their manufacturing processes are identified,together with advances in SP-treatment methods aimed at reducing those impacts.Recommendations for required future research addressing SP property and performance gaps are provided. 展开更多
关键词 Synthetic versus natural polymers Nanopolymers Drilling fluid additives LUBRICITY Clay swelling Hole cleaning
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Recent advances and innovations in the design and fabrication of wearable flexible biosensors and human health monitoring systems based on conjugated polymers 被引量:1
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作者 Vinh Van Tran Viet-Duc Phung Daeho Lee 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期476-516,共41页
Wearable biosensors have received great interest as patient-friendly diagnostic technologies because of their high flexibility and conformability.The growing research and utilization of novel materials in designing we... Wearable biosensors have received great interest as patient-friendly diagnostic technologies because of their high flexibility and conformability.The growing research and utilization of novel materials in designing wearable biosensors have accelerated the development of point-of-care sensing platforms and implantable biomedical devices in human health care.Among numerous potential materials,conjugated polymers(CPs)are emerging as ideal choices for constructing high-performance wearable biosensors because of their outstanding conductive and mechanical properties.Recently,CPs have been extensively incorporated into various wearable biosensors to monitor a range of target biomolecules.However,fabricating highly reliable CP-based wearable biosensors for practical applications remains a significant challenge,necessitating novel developmental strategies for enhancing the viability of such biosensors.Accordingly,this review aims to provide consolidated scientific evidence by summarizing and evaluating recent studies focused on designing and fabricating CP-based wearable biosensors,thereby facilitating future research.Emphasizing the superior properties and benefits of CPs,this review aims to clarify their potential applicability within this field.Furthermore,the fundamentals and main components of CP-based wearable biosensors and their sensing mechanisms are discussed in detail.The recent advancements in CP nanostructures and hybridizations for improved sensing performance,along with recent innovations in next-generation wearable biosensors are highlighted.CPbased wearable biosensors have been—and will continue to be—an ideal platform for developing effective and user-friendly diagnostic technologies for human health monitoring. 展开更多
关键词 Conjugated polymers Wearable biosensors E-skin electronics Implantable biosensors Conductive polymer hydrogels
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Exploring innovative synthetic solutions for advanced polymer-based electrochromic energy storage devices:Phenoxazine as a promising chromophore
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作者 Catalin-Paul Constantin Mihaela Balan-Porcarasu Gabriela Lisa 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期433-452,共20页
The current investigation offers an innovative synthetic solution regarding electrochromic(EC)and energy storage applications by exploring phenoxazine(POZ)moiety.Subsequently,three POZ-based polymers(polyimide,polyazo... The current investigation offers an innovative synthetic solution regarding electrochromic(EC)and energy storage applications by exploring phenoxazine(POZ)moiety.Subsequently,three POZ-based polymers(polyimide,polyazomethine,and polyamide)were synthesized to ascertain the superior performer.The polyamide exhibited remarkable attributes,including high redox stability during 500 repetitive CVs,optical contrast of 61.98%,rapid response times of 1.02 and 1.38 s for coloring and bleaching,EC efficiency of 280 cm^(2)C^(-1).and decays of the optical density and EC efficiency of only 12.18%and 6.23%after 1000 cycles.Then,the energy storage performance of polyamide PA was tested,for which the following parameters were obtained:74.7 F g^(-1)(CV,scan rate of 10 mV s^(-1))and 118 F g^(-1)(GCD,charging current of 0.1 A g^(-1)).Then,the polyamide was tested in EES devices,which yielded the following EC parameters:an optical contrast of 62.15%,response times of 9.24 and 5.01 s for coloring and bleaching,EC efficiency of 178 cm^(2)C^(-1),and moderate decays of 20.25%and 23.24%for the optical density and EC efficiency after 500 cycles.The energy storage performance included a capacitance of 106 F g^(-1)(CV,scan rate of 0.1 mV s^(-1))and 9.23 F g^(-1)(GCD,charging current of 0.1 A g^(-1)),capacitance decay of 11.9%after500 cycles,and 1.7 V retention after 2 h.Also,two EES devices connected in series powered a 3 V LED for almost 30 s. 展开更多
关键词 POLYMERS PHENOXAZINE Electrochromic Energy storage Electrochromi cenergy storage devices
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Conjugated microporous polymers-scaffolded enzyme cascade systems with enhanced catalytic activity
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作者 Zhenhua Wu Jiafu Shi +6 位作者 Boyu Zhang Yushuai Jiao Xiangxuan Meng Ziyi Chu Yu Chen Yiran Cheng Zhongyi Jiang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期213-223,共11页
Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs... Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs)are constructed through co-entrapping glucose oxidase(GOx)and horseradish peroxidase(HRP),in which hydrogen peroxide(H_(2)O_(2))is the intermediate product.The interplay of low-resistance mass transfer pathway and appropriate pore wall-H_(2)O_(2)interactions facilitates the directed transfer of H_(2)O_(2),resulting in 2.4-fold and 5.0-fold elevation in catalytic activ-ity compared to free ECSs and separated ECSs,respectively.The substrate channeling effect could be regulated by altering the mass ratio of GOx to HRP.Besides,I-ECSs demonstrate excellent stabili-ties in harsh environments and multiple recycling. 展开更多
关键词 BIOCATALYSIS IMMOBILIZATION Enzyme cascade system Substrate channeling effect Conjugated microporous polymers
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Combination of Nitrogen-Rich Skeleton and Coordination Group:Synthesis of a High-Energy Primary Explosive Based on 1H-Tetrazole-5-Carbohydrazide
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作者 Tingwei Wang Zujia Lu +6 位作者 Shu Bu Baolong Kuang Lu Zhang Zhenxin Yi Kun Wang Shunguan Zhu Jianguo Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期271-277,共7页
The high energy coordination compounds Cu(TZCA)_(2)(ClO_(4))_(2)(ECCs-1) was prepared by 1H-tetrazole-5-carbohydrazide(TZCA) with a high energy skeleton and a strong coordination ability group.At the same time,the rea... The high energy coordination compounds Cu(TZCA)_(2)(ClO_(4))_(2)(ECCs-1) was prepared by 1H-tetrazole-5-carbohydrazide(TZCA) with a high energy skeleton and a strong coordination ability group.At the same time,the reaction activity of the ligand was explored,and the single crystal structure of it and intermediate were obtained.The structures of all substances were characterized by IR and EA.And the structure and composition of ECCs-1 are confirmed by ESP,AC,SEM and ICP-OES.Physical and chemical properties tests show that ECCs-1 has an acceptable thermal stability(T_(d)=177℃) and extremely sensitive mechanical stimulation(IS=1 J,FS=5 N).The comprehensive performance test results show that ECCs-1 has excellent initiation ability.In addition,the decomposition mechanism of ECCs-1 is explored from two aspects of experiment and theoretical calculation. 展开更多
关键词 1H-tetrazole-5-carbohydrazide Primary explosive Decomposition mechanism Coordination polymers Laser
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Artificial Intelligence Prediction of One-Part Geopolymer Compressive Strength for Sustainable Concrete
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作者 Mohamed Abdel-Mongy Mudassir Iqbal +3 位作者 M.Farag Ahmed.M.Yosri Fahad Alsharari Saif Eldeen A.S.Yousef 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期525-543,共19页
Alkali-activated materials/geopolymer(AAMs),due to their low carbon emission content,have been the focus of recent studies on ecological concrete.In terms of performance,fly ash and slag are preferredmaterials for pre... Alkali-activated materials/geopolymer(AAMs),due to their low carbon emission content,have been the focus of recent studies on ecological concrete.In terms of performance,fly ash and slag are preferredmaterials for precursors for developing a one-part geopolymer.However,determining the optimum content of the input parameters to obtain adequate performance is quite challenging and scarcely reported.Therefore,in this study,machine learning methods such as artificial neural networks(ANN)and gene expression programming(GEP)models were developed usingMATLAB and GeneXprotools,respectively,for the prediction of compressive strength under variable input materials and content for fly ash and slag-based one-part geopolymer.The database for this study contains 171 points extracted from literature with input parameters:fly ash concentration,slag content,calcium hydroxide content,sodium oxide dose,water binder ratio,and curing temperature.The performance of the two models was evaluated under various statistical indices,namely correlation coefficient(R),mean absolute error(MAE),and rootmean square error(RMSE).In terms of the strength prediction efficacy of a one-part geopolymer,ANN outperformed GEP.Sensitivity and parametric analysis were also performed to identify the significant contributor to strength.According to a sensitivity analysis,the activator and slag contents had the most effects on the compressive strength at 28 days.The water binder ratio was shown to be directly connected to activator percentage,slag percentage,and calcium hydroxide percentage and inversely related to compressive strength at 28 days and curing temperature. 展开更多
关键词 Artificial intelligence techniques one-part geopolymer artificial neural network gene expression modelling sustainable construction polymers
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Vanillin Based Polymers:VI.Poly(hydrovanilloin-furfural)and Poly(hydrovanilloin-5-hydroxymethylfurfural)
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作者 Ananda S.Amarasekara Gabriel Murillo Morales Raghava R.Kommalapati 《Journal of Renewable Materials》 EI CAS 2024年第9期1495-1506,共12页
Renewable resources based polymers provides a sustainable alternative to petroleum derived polymeric materials.As a part of our series on synthesis of vanillin based renewable polymers,we report the synthesis of poly(... Renewable resources based polymers provides a sustainable alternative to petroleum derived polymeric materials.As a part of our series on synthesis of vanillin based renewable polymers,we report the synthesis of poly(hydrovanilloin-furfural)[poly(HVL-Fur)]and poly(hydrovanilloin–5-hydromethylfurfural)[poly(HVL-5-HMF)].Vanillin was dimerized to a mixtures of meso/DL-hydrovanilloins with 94%meso product by electrochemical reductive coupling in aqueous sodium hydroxide using lead electrodes in quantitative yield.Then sodium hydroxide catalyzed condensation of hydrovanilloin with furfural in water at 80℃for 72 h was used to synthesize poly(HVL-Fur)with Mw=8600 g mol^(−1),PDI=1.28 in 78%yield.Similarly,condensation of hydrovanilloin with 5-hydroxymethylfurfural at 80℃for 48 h produced poly(HVL-5-HMF)with Mw=12,100 g mol−1,PDI=1.27 in 68%yield.poly(HVL-Fur)and poly(HVL-5-HMF)showed similar Tg values of 59℃and 60℃,respectively;whereas melting behaviors are dissimilar with Tm 171℃–173℃and 148℃–182℃,respectively. 展开更多
关键词 VANILLIN hydrovanilloin FURFURAL 5-HYDROXYMETHYLFURFURAL renewable polymers
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Renewable Polymers in Biomedical Applications:From the Bench to the Market
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作者 Rauany Cristina Lopes Tamires Nossa +3 位作者 Wilton Rogério Lustri Gabriel Lombardo Maria Inés Errea Eliane Trovatti 《Journal of Renewable Materials》 EI CAS 2024年第4期643-666,共24页
Polymers from renewable resources have been used for a long time in biomedical applications and found an irreplaceable role in some of them.Their uses have been increasing because of their attractive properties,contri... Polymers from renewable resources have been used for a long time in biomedical applications and found an irreplaceable role in some of them.Their uses have been increasing because of their attractive properties,contributing to the improvement of life quality,mainly in drug release systems and in regenerative medicine.Formulations using natural polymer,nano and microscale particles preparation,composites,blends and chemical modification strategies have been used to improve their properties for clinical application.Although many studies have been carried out with these natural polymers,the way to reach the market is long and only very few of them become commercially available.Vegetable cellulose,bacterial cellulose,chitosan,poly(lactic acid)and starch can be found among the most studied polymers for biological applications,some with several derivatives already established in the market,and others with potential for such.In this scenario this work aims to describe the properties and potential of these renewable polymers for biomedical applications,the routes from the bench to the market,and the perspectives for future developments. 展开更多
关键词 POLYMERS RENEWABLE biomedical applications MARKET
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Study of damage behavior and repair effectiveness of patch repaired carbon fiber laminate under quasi-static indentation loading
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作者 Alok Kumar Chinmaya Kumar Sahoo A.Arockiarajan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期29-41,共13页
Damage caused due to low-velocity impacts in composites leads to substantial deterioration in their residual strength and eventually provokes structural failure.This work presents an experimental investigation on the ... Damage caused due to low-velocity impacts in composites leads to substantial deterioration in their residual strength and eventually provokes structural failure.This work presents an experimental investigation on the effects of different patch and parent laminate stacking sequences on the enhancement of impact strength of Carbon Fiber Reinforced Polymers(CFRP)composites by utilising the adhesively bonded external patch repair technique.Damage evolution study is also performed with the aid of Acoustic Emission(AE).Two different quasi-isotropic configurations were selected for the parent laminate,viz.,[45°/45°/0°/0°]s and[45°/0°/45°/0°]s.Quasi Static Indentation(QSI)test was performed on both the pristine laminates,and damage areas were detected by using the C-scan inspection technique.Damaged laminates were repaired by using a single-sided patch of two different configurations,viz.,[45°/45°/45°/45°]and[45°/0°/0°/45°],and employing a circular plug to fill the damaged hole.Four different combinations of repaired laminates with two configurations of each parent and patch laminate were produced,which were further subjected to the QSI test.The results reveal the effectiveness of the repair method,as all the repaired laminates show higher impact resistance compared to the respective pristine laminates.Patches of[45°/0°/0°/45°]configuration when repaired by taking[45°/45°/0°/0°]s and[45°/0°/45°/0°]s as parents exhibited 68%and 73%higher peak loads,respectively,than the respective pristine laminates.Furthermore,parent and patch of configuration[45°/0°/45°/0°]s and[45°/0°/0°/45°],respectively,attain the highest peak load,whereas[45°/45°/0°/0°]s and[45°/45°/45°/45°]combinations possess the most gradual decrease in the load. 展开更多
关键词 Carbon fiber reinforced polymers(CFRP) Quasi-isotropic laminate Quasi static indentation(QSI) Acoustic emission(AE) Composite repair
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《Angew》刊发袁亮团队在生物基高分子材料领域新进展
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《安徽农业大学学报》 CAS CSCD 2024年第3期494-494,共1页
近日,安徽农业大学林学与园林学院袁亮教授在国际顶级学术期刊《德国应用化学》(Angewandte Chemie International Edition,中科院1区,影响因子=16.6)发表题为《巯基-醛基缩聚制备生物基动态可降解酚类高分子》(《Thiol-Aldehyde Polyco... 近日,安徽农业大学林学与园林学院袁亮教授在国际顶级学术期刊《德国应用化学》(Angewandte Chemie International Edition,中科院1区,影响因子=16.6)发表题为《巯基-醛基缩聚制备生物基动态可降解酚类高分子》(《Thiol-Aldehyde Polycondensation for Bio-based Adaptable and Degradable Phenolic Polymers》)的研究论文。该论文被选为“Very Important Paper”,并作为Inside Cover进行报道。 展开更多
关键词 安徽农业大学 应用化学 POLYMERS 学术期刊 生物基高分子
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Application of the Shrinking Particle Model for the Evaluation of Molecular Recyclability of PET versus Semi-Aromatic Polyesters
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作者 Jack van Schijndel Sanne de Krom +2 位作者 Dennis Molendijk Koen van Beurden Amarante Böttger 《Open Journal of Physical Chemistry》 2024年第2期21-35,共15页
The molecular recyclability of poly (ethylene terephthalate) (PET) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-S) is e... The molecular recyclability of poly (ethylene terephthalate) (PET) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-S) is evaluated in this study. PET is an extensively used aromatic polyester, and poly-H, poly-G, and poly-S can be considered semi-aromatic poly (lactic acid) modifications. All these polyesters have been depolymerized at neutral pH and by acid- and base-catalyzed hydrolysis at two temperatures, i.e., 50˚C and 80˚C. Base-catalyzed depolymerization of virgin PET leads to an isolated yield of 38% after 48 hours of reaction at 80˚C. Contrary to these results for PET, almost all the monomers of the semi-aromatic polyesters poly-H, poly-G, and poly-S are recovered with isolated yields larger than 90% at the same temperature after 15 minutes in a facile manner. A shrinking particle model used to determine the global kinetics of the base-catalyzed depolymerization showed that the rate rises with increasing temperature. Using the shrinking particle model, the intrinsic reaction rate constants were determined. It has been demonstrated that the rate coefficients of the depolymerization of the semi-aromatic polyesters poly-H, poly-G, and poly-S are between 2 and 3 orders of magnitude higher than those for PET. 展开更多
关键词 DEPOLYMERIZATION Molecular Recycling Poly-H Poly-G Poly-S PET Circular Polymers
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Application of Pomegranate Rind Extract for Improvement of Functional Properties of Various Materials—A Critical Review
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作者 Habeebunissa Nooman Narayanan Gokarneshan +9 位作者 Murugan Umamaheswari Muthumani Dhiliphan Kumar Usha Kumari Ratna Jayagopal Lavanya Senthamarai Kannan Umamageshwari Sona Mohandas Anton Zahurudeen Shahanaz Venkatesan Sathya David Piriadarshani Chokkanathan Kayalvizhi 《Open Journal of Composite Materials》 2024年第2期71-90,共20页
Pomegranate rind is abundantly available as a waste material. Pomegranate Rind Extract (PRE) can be applied to cotton fabrics for its natural colours, as a mordanting agent and also for imparting certain functional pr... Pomegranate rind is abundantly available as a waste material. Pomegranate Rind Extract (PRE) can be applied to cotton fabrics for its natural colours, as a mordanting agent and also for imparting certain functional properties such as fire retardancy and antimicrobial properties. This paper reviews the feasibility of Pomegranate Rind Extract to improve the functional properties of cellulosic fabrics. Studies show that varying concentrations and higher temperatures that were used to apply the extract on the fabric, resulted in enhanced functional properties. At a particular concentration, the treated fabric showed a 15 times lower burning rate in comparison with the control fabric. Also, antimicrobial efficacy has been observed against Gram-positive and Gram-negative bacteria. Due to the natural colouring material, it can be used as a natural dye on cotton material. The fire retardancy of pomegranate rind extract was tested on jute material under varying alkalinity. Research has indicated that pomegranate rind extract could be used to dye polyamide as well. The rubbing and wash fastness of the finished fabrics is good. The light fastness was fair, and its antibacterial efficiency against tested bacteria was good. 展开更多
关键词 Natural Polymers Synthetic Polymers Pomegranate Rind Extract (PRE) DYEING Functional Property
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Innovative Methods of Synthesis and Characterization for Molecularly Imprinted Polymers
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作者 Youyao Luo 《Open Journal of Applied Sciences》 2024年第9期2559-2579,共21页
The characterization of these molecularly imprinted polymers is essential to understanding their binding dynamics and structural properties. Through the analysis of the current research, it is found that there are ove... The characterization of these molecularly imprinted polymers is essential to understanding their binding dynamics and structural properties. Through the analysis of the current research, it is found that there are overlaps in the methods used by scholars. The Langmuir equation is frequently applied to model the adsorption isotherms of MIPs, providing critical insight into the capacity and affinity of the binding sites. Infrared Spectroscopy (IR) plays a crucial role in identifying the functional groups involved in the imprinting process and confirming the successful formation of specific binding sites. UV-visible spectrophotometry is employed to monitor the absorption characteristics of the polymers, offering data on the interactions between the template molecules and the polymer matrix. Transmission Electron Microscopy (TEM) provides detailed visualization of the internal structure of MIPs at the nanoscale, revealing the morphology and size of the imprinted cavities. Thermogravimetric Analysis (TGA) assesses the thermal stability and composition of the polymers, identifying decomposition patterns that are indicative of the material’s robustness under different conditions. Finally, the Laser Particle Size Analyzer is used to measure the size distribution of the polymer particles, which is critical for determining the uniformity and efficiency of the imprinting process. The six characterization methods discussed in this paper provide a comprehensive understanding of MIP, and it is hoped that in the future, more optimized design solutions will emerge and their applications in various fields will be enhanced. 展开更多
关键词 Molecularly Imprinted Polymers Langmuir Equation Infrared Spectroscopy UV Visible Spectrophotometry Transmission Electron Microscopy
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Composite polymer electrolyte reinforced by graphitic carbon nitride nanosheets for room-temperature all-solid-state lithium batteries 被引量:2
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作者 Qingyue Han Suqing Wang +2 位作者 Wenhan Kong Bing Ji Haihui Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期257-263,共7页
By virtue of the flexibility and safety, polyethylene oxide(PEO) based electrolytes are regarded as an appealing candidate for all-solid-state lithium batteries. However, their application is limited by the poor ionic... By virtue of the flexibility and safety, polyethylene oxide(PEO) based electrolytes are regarded as an appealing candidate for all-solid-state lithium batteries. However, their application is limited by the poor ionic conductivity at room temperature, narrow electrochemical stability window and uncontrolled growth of lithium dendrite. To alleviate these problems, we introduce the ultrathin graphitic carbon nitride nanosheets(GCN) as advanced nanofillers into PEO based electrolytes(GCN-CPE). Benefiting from the high surface area and abundant surface N-active sites of GCN, the GCN-CPE displays decreased crystallinity and enhanced ionic conductivity. Meanwhile, Fourier transform infrared and chronoamperometry studies indicate that GCN can facilitate Li+migration in the composite electrolyte. Additionally, the GCN-CPE displays an extended electrochemical window compared with PEO based electrolytes. As a result, Li symmetric battery assembled with GCN-CPE shows a stable Li plating/stripping cycling performance, and the all-solid-state Li/LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622) batteries using GCN-CPE exhibit satisfactory cyclability and rate capability in a voltage range of 3-4.2 V at 30 ℃. 展开更多
关键词 Electrolytes POLYMERS Graphitic carbon nitride nanosheets Composites Room temperature All-solid-state battery
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Metal organic polymers with dual catalytic sites for oxygen reduction and oxygen evolution reactions 被引量:3
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作者 Sijia Liu Minghao Liu +4 位作者 Xuewen Li Shuai Yang Qiyang Miao Qing Xu Gaofeng Zeng 《Carbon Energy》 SCIE CSCD 2023年第5期127-137,共11页
Metal-organic frameworks and covalent organic frameworks have been widely employed in electrochemical catalysis owing to their designable skeletons,controllable porosities,and well-defined catalytic centers.However,th... Metal-organic frameworks and covalent organic frameworks have been widely employed in electrochemical catalysis owing to their designable skeletons,controllable porosities,and well-defined catalytic centers.However,the poor chemical stability and low electron conductivity limited their activity,and single-functional sites in these frameworks hindered them to show multifunctional roles in catalytic systems.Herein,we have constructed novel metal organic polymers(Co-HAT-CN and Ni-HAT-CN)with dual catalytic centers(metal-N_(4) and metal-N_(2))to catalyze oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).By using different metal centers,the catalytic activity and selectivity were well-tuned.Among them,Co-HAT-CN catalyzed the ORR in a 4e^(-)pathway,with a half-wave potential of 0.8 V versus RHE,while the Ni-HAT-CN catalyze ORR in a 2e^(-)pathway with H_(2)O_(2) selectivity over 90%.Moreover,the Co-HAT-CN delivered an overpotential of 350 mV at 10 mA cm^(-2) with a corresponding Tafel slope of 24 mV dec^(-1) for OER in a 1.0 M KOH aqueous solution.The experimental results revealed that the activities toward ORR were due to the M-N_(4) sites in the frameworks,and both M-N_(4) and M-N_(2) sites contributed to the OER.This work gives us a new platform to construct bifunctional catalysts. 展开更多
关键词 covalent organic frameworks metal organic polymers oxygen evolution reaction oxygen reduction reaction single atom catalysts
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3D Raman mapping as an analytical tool for investigating the coatings of coated drug particles 被引量:1
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作者 Georgia Koutentaki Pavel Krýsa +3 位作者 Dan Trunov Tomás Pekarek Marketa Pislova Miroslav Soos 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第3期276-286,共11页
The properties of dry-coated paracetamol particles(fast-dissolving model drug)with carnauba wax particles as the coating agent(dissolution retardant)were investigated.Raman mapping technique was used to non-destructiv... The properties of dry-coated paracetamol particles(fast-dissolving model drug)with carnauba wax particles as the coating agent(dissolution retardant)were investigated.Raman mapping technique was used to non-destructively examine the thickness and homogeneity of coated particles.The results showed that the wax existed in two forms on the surface of the paracetamol particles,forming a porous coating layer:i)whole wax particles on the surface of paracetamol and glued together with other wax surface particles,and ii)deformed wax particles spread on the surface.Regardless of the final particle size fraction(between 100 and 800 mm),the coating thickness had high variability,with average thickness of 5.9±4.2 mm.The ability of carnauba wax to decrease the dissolution rate of paracetamol was confirmed by dissolution of powder and tablet formulations.The dissolution was slower for larger coated particles.Tableting further reduced the dissolution rate,clearly indicating the impact of subsequent formulation processes on the final quality of the product. 展开更多
关键词 Raman mapping Dry-coating DISSOLUTION Particle coating thickness POLYMERS
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Pyridine terminated polyurethane dendrimer/chlorinated butyl rubber nanocomposites with excellent mechanical and damping properties 被引量:1
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作者 Jiacheng Chen Jincheng Wang +2 位作者 Shuhong Li Kailing Xiang Shiqiang Song 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期211-221,共11页
Due to the special viscoelastic property, traditional rubber with high performance has been widely used in human life and production. However, it is challenging to improve the damping property without sacrificing the ... Due to the special viscoelastic property, traditional rubber with high performance has been widely used in human life and production. However, it is challenging to improve the damping property without sacrificing the extensibility. In this work, a novel type of second-generation polyurethane dendrimer terminated with pyridine(G2-Py) was synthesized by using thiolactone chemistry and subsequently complexed with Zn ions. The structure and morphology of G2-Py were characterized. G2-Py-Zn2+was then mixed with chlorinated butyl rubber(CIIR) by a two-roll mill. A series of CIIR/G2-Py-Zn2+elastomers were obtained through vulcanization. CIIR/G2-Py-Zn2+elastomers could achieve high stretchability(a strain of ~1035%), high mechanical strength(a tensile stress of 7.64 MPa). This was benefitted from the friction between G2-Py and CIIR as well as variety of non-covalent bonds provided by G2-Py-Zn2+,which can dissipate energy to further improve the strength and extensibility. The coordination of Zn2+-pyridine was confirmed by Fourier transform infrared spectroscopy, stress relaxation and cycle tensile test. To further investigate the morphology and damping properties of the elastomers, scanning electron microscopy and dynamic mechanical analysis were performed. CIIR-5 showed the best damping performance with higher tan δ_(max) and wider effective damping temperatures. Therefore, this dendrimer modification technology provides wider applications for CIIR elastomers in daily life. 展开更多
关键词 Coordination bonds Hydrogen bonds Polyurethane dendrimer NANOSTRUCTURE Polymers Composites
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Electrophoretic deposition of hybrid organic-inorganic PTFE/Al/CuO energetic film 被引量:1
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作者 Yan-jun Yin Feng Hu +1 位作者 Le-hua Cheng Xiao-dong Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第4期112-118,共7页
Thermite films are typical energetic materials(EMs)and have great value in initiating explosive devices.However,research in thermite film preparation is far behind that of research in thermite powders.Electrophoretic ... Thermite films are typical energetic materials(EMs)and have great value in initiating explosive devices.However,research in thermite film preparation is far behind that of research in thermite powders.Electrophoretic deposition(EPD)is an emerging,rapid coating method for film fabrication,including of energetic composite films.In this work,a polytetrafluoroethylene(PTFE)/Al/CuO organic-inorganic hybrid energetic film was successfully obtained using the above method for the first time.The addition of lithocholic acid as a surfactant into the electroplating suspension enabled PTFE to be charged.The combustion and energy release were analyzed by means of a high-speed camera and differential scanning calorimetery(DSC).It was found that the combustion process and energy release of PTFE/Al/CuO were much better than that of Al/CuO.The main reason for the excellent combustion performance of the hybrid PTFE/Al/CuO system was that the oxidability of PTFE accelerated the redox reaction between Al and CuO.The prepared PTFE/Al/CuO film was also employed as ignition material to fire a B-KNO_3 explosive successfully,indicating considerable potential for use as an ignition material in micro-ignitors.This study sheds light on the preparation of fluoropolymer-containing organic-inorganic hybrid energetic films by one-step electrophoretic deposition. 展开更多
关键词 Energetic film Electrophoretic deposition Fluorine-based polymers Combustion performance THERMITE
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A semi-immobilized sulfur-rich copolymer backbone with conciliatory polymer skeleton and conductive substrates for high-performance Li-S batteries 被引量:1
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作者 Tianpeng Zhang Zihui Song +6 位作者 Jinfeng Zhang Wanyuan Jiang Runyue Mao Borui Li Siyang Liu Xigao Jian Fangyuan Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期510-518,I0012,共10页
Sulfur-rich polymers have gained a great deal of attention as the next-generation active materials in lithium-sulfur(Li-S)batteries due to their low cost,environmental compatibility,naturally sulfur uniform dispersion... Sulfur-rich polymers have gained a great deal of attention as the next-generation active materials in lithium-sulfur(Li-S)batteries due to their low cost,environmental compatibility,naturally sulfur uniform dispersion,and distinctive structure covalently bonding with sulfur atoms.However,the poor electrical conductivity and undesirable additional shuttle effect still hinder the commercial application of sulfur-rich polymers.Herein,we report a flexible semi-immobilization strategy to prepare allylterminated hyperbranched poly(ethyleneimine)-functionalized reduced graphene oxide(A-PEI-EGO)as sulfur-rich copolymer backbone.The semi-immobilization strategy can effectively reconcile the demand for polymer skeleton and conductive substrates through forming quaternary ammonium groups and reducing oxygen-containing functional groups,resulting in enhanced skeleton adsorption capacity and substrate electronic conductivity,respectively.Furthermore,the stable covalent bonding connection based on polymer molecules(A-PEI)not only completely prevents the additional shuttle effect of lithiation organic molecules and even sulfur-rich oligomers,but provides more inverse vulcanization active sites.As a result,the as-prepared A-PEI-EGO-S cathodes display an initial discharge capacity of1338 m A h g^(-1)at a rate of 0.1 C and an outstanding cycling stability of 0.046%capacity decay per cycle over 600 cycles.Even under 6.2 mg cm^(-2)S-loaded and sparing electrolyte of 6μL mg^(-1),the A-PEI-EGO-S cathode can also achieve a superior cycling performance of 98%capacity retention after 60 cycles,confirming its application potential. 展开更多
关键词 Li-S batteries Sulfur-rich polymers Semi-immobilization strategy Demand reconciliation Outstanding cycling stability
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Conducting Polymers Meet Lithium-Sulfur Batteries:Progress,Challenges,and Perspectives 被引量:1
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作者 Xin Chen Chengcheng Zhao +6 位作者 Kai Yang Shiyi Sun Jinxin Bi Ningrui Zhu Qiong Cai Jianan Wang Wei Yan 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第5期159-182,共24页
Lithium-sulfur(Li-S)batteries have attracted increased interest because of the high theoretical energy density,low cost,and environmental friendliness.Conducting polymers(CPs),as one of the most promising materials us... Lithium-sulfur(Li-S)batteries have attracted increased interest because of the high theoretical energy density,low cost,and environmental friendliness.Conducting polymers(CPs),as one of the most promising materials used in Li-S batteries,can not only facilitate electron transfer and buffer the large volumetric change of sulfur benefiting from their porous structure and excellent flexibility,but also enable stronger physical/chemical adsorption capacity toward polysulfides(LiPSs)when doped with abundant heteroatoms to promote the sulfur redox kinetics and achieve the high sulfur loading.This review firstly introduces the properties of various CPs including structural CPs(polypyrrole(PPy),polyaniline(PANi),polyethylene dioxothiophene[PEDOT])and compound CPs(polyethylene oxide(PEO),polyvinyl alcohol(PVA)and poly(acrylic acid)[PAA]),and their application potential in Li-S batteries.Furthermore,the research progress of various CPs in different components(cathode,separator,and interlayer)of Li-S batteries is systematically summarized.Finally,the application perspective of the CPs in Li-S batteries as a potential guidance is comprehensively discussed. 展开更多
关键词 conducting polymers Li-S batteries modified materials POLYSULFIDES
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