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Residual alkali-evoked cross-linked polymer layer for anti-air-sensitivity LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)cathode 被引量:1
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作者 Chao Zhao Xuebao Li +7 位作者 Yun Zhao Jingjing He Yuanpeng Cao Wei Luo Ding Wang Jianguo Duan Xianshu Wang Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期450-458,共9页
High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)M... High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs. 展开更多
关键词 Lithium-ion batteries Nickel-rich layered cathode Residual alkalis cross-linked polyme rmodification Airsensitivity
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Mechanism of high Li-ion conductivity in poly(vinylene carbonate)-poly(ethylene oxide)cross-linked network based electrolyte revealed by solid-state NMR
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作者 Fan Li Tiantian Dong +5 位作者 Yi Ji Lixin Liang Kuizhi Chen Huanrui Zhang Guanglei Cui Guangjin Hou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期377-383,I0010,共8页
Solid polymer electrolytes(SPEs)have become increasingly important in advanced lithium-ion batteries(LIBs)due to their improved safety and mechanical properties compared to organic liquid electrolytes.Cross-linked pol... Solid polymer electrolytes(SPEs)have become increasingly important in advanced lithium-ion batteries(LIBs)due to their improved safety and mechanical properties compared to organic liquid electrolytes.Cross-linked polymers have the potential to further improve the mechanical property without trading off Li-ion conductivity.In this study,focusing on a recently developed cross-linked SPE,i.e.,the one based on poly(vinylene carbonate)-poly(ethylene oxide)cross-linked network(PVCN),we used solid-state nuclear magnetic resonance(NMR)techniques to investigate the fundamental interaction between the chain segments and Li ions,as well as the lithium-ion motion.By utilizing homonuclear/heteronuclear correlation,CP(cross-polarization)kinetics,and spin-lattice relaxation experiments,etc.,we revealed the structural characteristics and their relations to lithium-ion mobilities.It is found that the network formation prevents poly(ethylene oxide)chains from crystallization,which could create sufficient space for segmental tumbling and Li-ion co nductio n.As such,the mechanical property is greatly improved with even higher Li-ion mobilities compared to the poly(vinylene carbonate)or poly(ethylene oxide)based SPE analogues. 展开更多
关键词 ssNMR Lithium-ion mobility cross-link Solid polymer electrolyte
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Tuning the cross-linked structure of basic poly(ionic liquid)to develop an efficient catalyst for the conversion of vinyl carbonate to dimethyl carbonate
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作者 Zhaoyang Qi Shiquan Zhong +4 位作者 Huiyun Su Changshen Ye Limei Ren Ting Qiu Jie Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期106-116,共11页
Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium ... Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium methoxide basic catalyst to produce DMC through the transesterification reaction between vinyl carbonate and methanol.However,the utilization of this catalyst presents several challenges during the process,including equipment corrosion,the generation of solid waste,susceptibility to deactivation,and complexities in separation and recovery.To address these limitations,a series of alkaline poly(ionic liquid)s,i.e.[DVBPIL][PHO],[DVCPIL][PHO],and[TBVPIL][PHO],with different crosslinking degrees and structures,were synthesized through the construction of cross-linked polymeric monomers and functionalization.These poly(ionic liquid)s exhibit cross-linked structures and controllable cationic and anionic characteristics.Research was conducted to investigate the effect of the cross-linking degree and structure on the catalytic performance of transesterification in synthesizing DMC.It was discovered that the appropriate cross-linking degree and structure of the[DVCPIL][PHO]catalyst resulted in a DMC yield of up to 80.6%.Furthermore,this catalyst material exhibited good stability,maintaining its catalytic activity after repeated use five times without significant changes.The results of this study demonstrate the potential for using alkaline poly(ionic liquid)s as a highly efficient and sustainable alternative to traditional catalysts for the transesterification synthesis of DMC. 展开更多
关键词 Poly(ionic liquid) cross-linking degree Dimethyl carbonate production Transesterification reaction Mechanism
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Molecular Dynamics Study on Hydrothermal Response of PNIPAM:From Single Chain to Cross-Linked Polymer
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作者 Xianzhi Chen Dong Niu +1 位作者 Hongtao Gao Mu Du 《Frontiers in Heat and Mass Transfer》 EI 2024年第6期1743-1760,共18页
Thermosensitive hydrogel can integrate vapor molecular capture,in-situ liquefaction,and thermal-induced water release for freshwater capture.This study aimed to examine the dynamic behavior of poly(N-isopropylacrylami... Thermosensitive hydrogel can integrate vapor molecular capture,in-situ liquefaction,and thermal-induced water release for freshwater capture.This study aimed to examine the dynamic behavior of poly(N-isopropylacrylamide)(PNIPAM)single chain and cross-linking thermosensitive hydrogel through molecular dynamics simulation.Specifically,the impact of lower critical solution temperature(LCST)on the conformation of polymer chain and the interaction between water and polymer chain were also investigated.The polymer chain conformation underwent a transition from coil to globule when the temperature exceeded the LCST,indicating the temperature responsiveness of PNIPAM.Additionally,thermosensitive hydrogel samples with different cross-linking degrees(DOC)were studied,and relevant parameters such as the number of free water,the diffusion coefficient of water,and the pore size distribution were counted to evaluate the temperature responsiveness and water release characteristics of thermosensitive hydrogel. 展开更多
关键词 Thermosensitive hydrogel water harvesting coil to globule cross-linked molecular dynamics simulation
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PEI/SA/Cu三元体系改性荷正电纳滤膜及其脱盐性能
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作者 马晓华 梁晓康 许振良 《膜科学与技术》 CAS CSCD 北大核心 2024年第4期8-16,共9页
通过将海藻酸钠(SA)与聚乙烯亚胺(PEI)共混作为二次界面聚合反应的水相溶液,SA与PEI强相互作用使SA嵌入到聚酰胺层中,从而提高膜的致密性.随后通过Cu^(2+)与SA结合提高膜表面荷正电性,提高膜对多价阳离子的截留性能.对比研究了SA和Cu^(... 通过将海藻酸钠(SA)与聚乙烯亚胺(PEI)共混作为二次界面聚合反应的水相溶液,SA与PEI强相互作用使SA嵌入到聚酰胺层中,从而提高膜的致密性.随后通过Cu^(2+)与SA结合提高膜表面荷正电性,提高膜对多价阳离子的截留性能.对比研究了SA和Cu^(2+)浓度对复合膜物化性质、表面形貌及分离性能的影响.结果表明,荷正电纳滤膜的最佳制备条件为:SA质量分数为0.01%,Cu^(2+)浓度为25 mmol/L,所对应的PS/Cu-3复合膜亲水性提高.与Control-PEI膜相比,其通量提高了257%,为(40.0±0.8)L/(m^(2)·h),对MgCl2的截留率从92.0%提升至97.1%,且具有良好的耐压性和稳定性. 展开更多
关键词 pei/SA/Cu三元体系改性 荷正电 纳滤膜 脱盐性能
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PEI联合术中房角镜下房角分离及房角切开术治疗中晚期PACG合并白内障 被引量:1
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作者 高思佳 闻郁 +2 位作者 万茜茜 刘贺婷 陶黎明 《国际眼科杂志》 CAS 2024年第6期864-869,共6页
目的:评价超声乳化白内障吸除人工晶状体植入术(PEI)联合术中房角镜直视下房角分离术(GSL)及房角切开术(GT)治疗中晚期原发性闭角型青光眼(PACG)合并白内障的效果。方法:回顾性病例系列研究方法。收集2021-12-01/2023-03-31在安徽医科... 目的:评价超声乳化白内障吸除人工晶状体植入术(PEI)联合术中房角镜直视下房角分离术(GSL)及房角切开术(GT)治疗中晚期原发性闭角型青光眼(PACG)合并白内障的效果。方法:回顾性病例系列研究方法。收集2021-12-01/2023-03-31在安徽医科大学第二附属医院手术的中晚期PACG合并白内障患者62例65眼,根据手术方式不同分为两组:观察组30例32眼行PEI+GSL+GT,对照组32例33眼行PEI+GSL。评估两组患者术前,术后1 d, 1 wk, 1、3、6 mo眼压、最佳矫正视力(BCVA)和抗青光眼药物使用数量。术前和术后6 mo时分别评估视野、杯盘比、前房角开放范围、前房深度、RNFL平均厚度。结果:PEI+GSL+GT组术后6 mo眼压和平均眼压降幅(16.68±2.65、11.12±8.53 mmHg)与PEI+GSL组(18.71±2.51、8.32±4.17 mmHg)有显著差异(P<0.05),眼压降幅率无差异(44.57%±21.79%和35.20%±17.94%,P>0.05)。术后6 mo两组抗青光眼药物使用数量、BCVA、前房深度、房角关闭范围均较术前改善(均P<0.01),PEI+GSL+GT组术后6 mo的药物减少数量和房角开放范围均大于PEI+GSL组(P<0.05),其余指标两组间比较均无差异(均P>0.05)。两组术后6 mo的视野平均偏差、杯盘比及RNFL平均厚度较术前均无差异(均P>0.05)。PEI+GSL+GT组手术完全成功率为81%(26/32),手术条件成功率为94%(30/32);PEI+GSL组手术完全成功率为58%(19/33),手术条件成功率为76%(25/33)。两组间手术成功率均有差异(完全成功率χ^(2)=4.275,P=0.039;条件成功率χ^(2)=4.040,P=0.044)。两组患者均未见危及视力的并发症及再次手术。结论:对于中晚期原发性闭角型青光眼合并白内障患者,采用PEI+GSL+GT治疗比PEI+GSL治疗更有效。 展开更多
关键词 原发性闭角型青光眼(PACG) 白内障 房角切开术 房角分离术 微创青光眼手术 超声乳化白内障吸除人工晶状体植入(pei) 前房角镜检查
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Study on the Soy Protein-Based Adhesive Cross-Linked by Glyoxal 被引量:6
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作者 Zhigang Wu Jiankun Liang +3 位作者 Hong Lei Bengang Zhang Xuedong Xi Lifen Li 《Journal of Renewable Materials》 SCIE EI 2021年第2期205-218,共14页
Based on the ESI-MS and ^(13)C-NMR analysis of the forms of glyoxal in acidic and alkaline solutions,the soy-based adhesive cross-linked by glyoxal was prepared in this work.The results showed that glyoxal existed in ... Based on the ESI-MS and ^(13)C-NMR analysis of the forms of glyoxal in acidic and alkaline solutions,the soy-based adhesive cross-linked by glyoxal was prepared in this work.The results showed that glyoxal existed in water in different forms at different pH levels.Under alkaline conditions,glyoxal transformed to glycolate through the intramolecular disproportionation reaction.Under acidic conditions,although some of glyoxal transformed to glycolate as what happened under alkaline conditions,most of glyoxal molecules existed in the form of fiveor six-membered cyclic ether structure.No ethylene tetraol or free aldehyde group was actually detected under these conditions.Although glyoxal reacted with soy protein under both acidic and alkaline conditions,alkaline conditions were more favorable for the improvement of mechanical performance and water resistance of soybased adhesives than acid conditions. 展开更多
关键词 GLYOXAL soy protein-based adhesive cross-link
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MOFs负载聚乙烯亚胺(PEI)对硫化氢的吸附 被引量:1
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作者 杨永杰 刘萱 +2 位作者 杨超 王业双 樊惠玲 《煤炭学报》 EI CAS CSCD 北大核心 2024年第7期3225-3234,共10页
煤炭清洁高效利用是当下煤炭资源发展的主题,煤炭加工利用过程中会产生以硫化氢(H_(2)S)为主的硫化物,对生产和环境造成了不利影响。近年来,吸附脱硫因其高脱硫效率、高精度、操作简单等优点成为广泛使用的脱硫方法。金属−有机框架材料(... 煤炭清洁高效利用是当下煤炭资源发展的主题,煤炭加工利用过程中会产生以硫化氢(H_(2)S)为主的硫化物,对生产和环境造成了不利影响。近年来,吸附脱硫因其高脱硫效率、高精度、操作简单等优点成为广泛使用的脱硫方法。金属−有机框架材料(MOFs)具有大的比表面积和孔隙率、易于修饰和功能化的优势,在气体吸附领域具有很大的潜力。聚乙烯亚胺(PEI)是同时含有伯、仲、叔胺的高分子聚合物,对H_(2)S有强亲和力并发生可逆的化学反应,将PEI引入MOFs中有望进一步提升H_(2)S吸附性能。为此,采用浸渍法制备了PEI负载的MIL-101(Cr)、UiO-66、MOF-801、ZIF-8吸附剂,研究了载体类型和PEI负载量对H_(2)S吸附性能的影响,考察了吸附剂的循环使用能力。结果表明,负载PEI后,所有载体的吸附容量均有所提高,ZIF-8提高的最多,归因于ZIF-8载体本身大的比表面积、孔体积、负载后晶体结构的保持以及PEI与ZIF-8之间的相互作用。而其余MOFs由于比表面积和孔体积较小或负载PEI后结构发生破坏,负载PEI之后的吸附容量不理想。PEI的负载量会影响ZIF-8的孔隙结构和骨架的稳定性;50%(质量分数)PEI负载后的ZIF-8穿透硫容最高,为56.3 mg/g,是载体本身的55倍。再生循环实验表明,负载PEI的ZIF-8只能实现极少部分再生,并且负载量低的吸附剂的吸附循环性能比负载量高的更好,PEI的引入使ZIF-8更易遭受H_(2)S的进攻生成ZnS。 展开更多
关键词 MOFS 吸附脱硫 pei 再生循环
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Applications of Crown Ether Cross-Linked Chitosan for the Analysis of Lead and Cadmium in Environmental Water Samples 被引量:6
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作者 Tang Yu-rong Zhang Shu-qin +1 位作者 Wang Yu-ting Feng Xue-song 《Wuhan University Journal of Natural Sciences》 CAS 2002年第2期217-221,共5页
A new type of crown ether cross-linked chitosan was synthesized by the reaction of chitosan with 4,4′-dibromodibenzo-18-crown-6 (Br-DBC). Its token structure was analyzed with FT-IR and NMR and the adsorption behavio... A new type of crown ether cross-linked chitosan was synthesized by the reaction of chitosan with 4,4′-dibromodibenzo-18-crown-6 (Br-DBC). Its token structure was analyzed with FT-IR and NMR and the adsorption behaviors for lead and cadmium in environmental water samples by FAAS were studied. In addition the best analysis conditions were discussed and the adsorption mechanism was explained. As the enrichment factor is above 100, both recoveries are 94%–106%, the detection limits of lead and cadmium are 0.5μg·L?1 and 0.04 μg·L?1 and the relatively standard deviations of lead and cadmium are 3.1% and 2.8% respectively, this new method was successfully applied to the determination of environmental water samples. This method is fast and simple and it greatly enhances the determination ability of FAAS for lead and cadmium. 展开更多
关键词 Crown ether cross-linked chitosan lead and cadmium ADSORPTION FAAS
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Adsorptive Removal of Copper Ions from Aqueous Solution Using Cross-linked Magnetic Chitosan Beads 被引量:13
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作者 黄国林 杨婥 +1 位作者 章凯 SHI Jeffrey 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第6期960-966,共7页
The performance of cross-linked magnetic chitosan, coated with magnetic fluids and cross-linked with ePichlorohydrin, was investigated for the adsorption of Copper (Ⅱ) from aqueous solutions. Infrared spectra of ch... The performance of cross-linked magnetic chitosan, coated with magnetic fluids and cross-linked with ePichlorohydrin, was investigated for the adsorption of Copper (Ⅱ) from aqueous solutions. Infrared spectra of chitosan before and after modification showed that the coating and cross-linking are effective. Experiments were performed at different pH of solution and contact time, and appropriate conditions for the adsorption of Cu(Ⅱ) were determined. Experimental equilibrium data were correlated with Langmuir and Freundlich isotherms for determination of the adsorption potential. The results showed that the Langmuir isotherm was better compared with the Freundlich isotherm, and the uptake of Cu(Ⅱ) was 78.13 mg·g^- 1. The kinetics of adsorption corresponded with the first-order Langergren rate equation, and Langergren rate constants were determined. 展开更多
关键词 adsorption of copper (Ⅱ) cross-linked magnetic chitosan Langmuir isotherm Langergren rate equation
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Simultaneously enhanced moisture tolerance and defect passivation of perovskite solar cells with cross-linked grain encapsulation 被引量:3
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作者 Ke Xiao Qiaolei Han +6 位作者 Yuan Gao Shuai Gu Xin Luo Renxing Lin Jia Zhu Jun Xu Hairen Tan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期455-462,共8页
The grain surfaces(film surface and grain boundary)of polycrystalline perovskite films are vulnerable sites in solar cells since they pose a high defect density and initiate the degradation of perovskite absorber.Achi... The grain surfaces(film surface and grain boundary)of polycrystalline perovskite films are vulnerable sites in solar cells since they pose a high defect density and initiate the degradation of perovskite absorber.Achieving simultaneously defect passivation and grain protection from moisture is crucial for the viability of perovskite solar cells.Here,an in situ cross-linked grain encapsulation(CLGE)strategy that improves both device stability and defect passivation is reported.Cross-linkable semiconducting small molecules are mixed into the antisolvent to uniformly form a compact and conducting cross-linked layer over the grain surfaces.This cross-linked coating layer not only passivates trap states and facilitates hole extraction,but also enhances the device stability by preventing moisture diffusion.Using the CLGE strategy,a high power conversion efficiency(PCE)of 22.7%is obtained in 1.55-eV bandgap planar perovskite solar cells.The unencapsulated devices with CLGE exhibit significantly enhanced device stability again moisture and maintain>90%of their initial PCE after shelf storage under ambient condition for over10,000 h. 展开更多
关键词 Perovskite solar cell cross-link Defect passivation Stability Moisture tolerance
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Cross-Linked Hollow Graphitic Carbon as Low-Cost and High-Performance Anode for Potassium Ion Batteries 被引量:5
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作者 Yanhong Feng Suhua Chen +2 位作者 Dongyang Shen Jiang Zhou Bingan Lu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2021年第3期451-457,共7页
Large-scale and low-cost preparation of carbon-based potassium anode with long life and high capacity is one of the footstones for the development of potassium ion batteries(PIBs).Herein,a low-cost carbon-based materi... Large-scale and low-cost preparation of carbon-based potassium anode with long life and high capacity is one of the footstones for the development of potassium ion batteries(PIBs).Herein,a low-cost carbon-based material,cross-linked hollow graphitic carbon(HGC),is large scale synthesized to apply for PIBs anode.Its hollow structure can afford sufficient space to overcome the damage caused by the volume expansion of graphitic carbon(GC).While the cross-linked structure forms a compact interconnection network that allows electrons to rapid transfer between different GC frameworks.Electrochemical measurements demonstrated that the HGC anode exhibited low charge/discharge plateau(about 0.25 V and 0.1 V)and excellent specific capacity as high as 298 m A h g^(-1)at the current density of 50 m A g^(-1).And more important,after 200 cycles the capacity of HGC anode still shows 269 m A h g^(-1)(the decay rate of per cycle is only 0.048%).Meanwhile,the use of commercial traditional electrolyte(KPF_(6))and cheap raw materials that provide new hope for trying and realizing the large-scale production of PIBs based on carbon anode materials. 展开更多
关键词 cross-linked hollow structure graphitic material high reversibility potassium ion battery
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Study of action mechanisms and properties of Cr^(3+) cross-linked polymer solution with high salinity 被引量:8
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作者 Lu Xiangguo Liu Jinxiang +2 位作者 Wang Rongjian Liu Yigang Zhang Song 《Petroleum Science》 SCIE CAS CSCD 2012年第1期75-81,共7页
Performance characteristics of partially hydrolyzed polyacrylamide (HPAM) and cross- linked polymer (CLP, Cr^3+ as the cross linker) solutions have been investigated. A Brookfield viscometer, rheometer, dynamic l... Performance characteristics of partially hydrolyzed polyacrylamide (HPAM) and cross- linked polymer (CLP, Cr^3+ as the cross linker) solutions have been investigated. A Brookfield viscometer, rheometer, dynamic light scattering system, and core flow device have been used to measure the viscosity, viscoelasticity, polymer coil dimensions, molecular configuration, flow characteristics, and profile modification. The results show that, under conditions of high salinity and low HPAM and Cr^3+ concentrations, cross-linking mainly occurred between different chains of the same HPAM molecule in the presence of Cr^3+, and a cross-linked polymer (CLP) system with a local network structure was formed. Compared with an HPAM solution of the same concentration, the apparent viscosity of the CLP solution increased slightly or remained almost unchanged, but its viscoelasticity (namely storage modulus, loss modulus, and first normal stress difference) increased, and the resistance coefficient and residual resistance coefficient increased significantly. This indicates that the CLP solution exhibits a strong capability to divert the sequentially injected polymer flood from high-permeability zones to low- permeability zones in a reservoir. Under the same HPAM concentration conditions, the dimensions of polymer coils in the CLP solution increased slightly compared with the dimensions of polymer coils in HPAM solution, which were smaller than the rock pores, indicating that the cross-linked polymer solution was well adapted to reservoir rocks. Core flood experiments show that at the same cost of reagent, the oil recovery by CLP injection (HPAM-1, Cr^3+ as the cross linker) is 3.1% to 5.2% higher than that by HPAM- 2 injection. 展开更多
关键词 cross-linked polymer solution apparent viscosity VISCOELASTICITY polymer coil dimension molecular configuration flow characteristics profile modification
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Study on the Structure of Peroxide Cross-Linked Polyethylene Pipes with Several Stabilizers 被引量:4
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作者 Hideo Hirabayashi Akinori Iguchi +3 位作者 Kazushi Yamada Hiroyuki Nishimura Kazuhisa Ikawa Hidekazu Honma 《Materials Sciences and Applications》 2013年第9期497-503,共7页
Cross-linked polyethylene (PEX) pipes used in hot water supply are required for high mechanical strength and high creep resistance at high temperature. Especially PEX-a pipes which are made by peroxide cross-linking h... Cross-linked polyethylene (PEX) pipes used in hot water supply are required for high mechanical strength and high creep resistance at high temperature. Especially PEX-a pipes which are made by peroxide cross-linking have better performance, such as creep resistance and thermal shock resistance than the pipes made by the other cross-linking method. Because the PEX-a pipes indicate the higher cross-link degree as compared with the other PEX pipes. In this study, the PEX-a pipes which were mixed with several stabilizers were tested to evaluate the effects on cross-link degree and the oxygen induction time. And also they are evaluated with the chlorine aqueous solution by the performance of the long-term hydrostatic pressure test and the long-term hydro dynamic pressure test. As a result, it was found that the combination of antioxidants for PEX-a pipes plays an important role to prolong the oxygen induction time without inhibiting the cross-linking. From the results of the 1H pulsed NMR measurement over the melting point of polyethylene, it was found that each peroxide PEX pipe with different antioxidant combinations indicated the different proportion and crosslink density of cross-linked region, in addition, that these pipes had the effective structure of cross-linking for the hydrostatic and hydrodynamic pressure test with the chlorine aqueous solution. Therefore, it was considered to be useful results for studies of the stricture of cross-linking of polyethylene. 展开更多
关键词 cross-linked Polyethylene PEX-a PEROXIDE STRUCTURE of cross-linking
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An Efficient Extraction-Free Method for Oxidative Desulfurization of Model Fuels Employing Cross-Linked Polyionic Liquid Phosphotungstate Catalysts 被引量:2
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作者 Yuan Dandan Zhang Ling +2 位作者 Yin Guoqing Wang Yuanyuan Zhang Jiaojing 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2022年第3期10-20,共11页
An efficient extraction-free oxidative desulfurization(ODS)process using a series of cross-linked polyionic liquid phosphotungstate(CLPIL-PW)catalysts is reported.The cross-linked PILs were prepared with DVB and 1-n-a... An efficient extraction-free oxidative desulfurization(ODS)process using a series of cross-linked polyionic liquid phosphotungstate(CLPIL-PW)catalysts is reported.The cross-linked PILs were prepared with DVB and 1-n-alkyl-3-vinyl imidazole hydrobromide(alkyl=ethyl,butyl,octyl,dodecyl),and were then assembled with phosphotungstic acid(H_(3)PW_(12)O_(40))to form the catalysts.The CLPIL-PWs have been applied to the oxidative removal of dibenzothiophene(DBT)from model oil with H_(2)O_(2) as an oxidant.The effects of ionic liquid(IL)cationic species,varying the DVB/IL molar ratio in the polymerization process,and varying operating conditions were investigated.The CLPIL-PWs were characterized by inductively coupled plasma(ICP)mass spectrometry,elemental analysis,scanning electron microscopy(SEM),Fourier transform infra-red(FTIR)spectroscopy,X-ray diffraction(XRD),^(13)C and^(31)P nuclear magnetic resonance(NMR)spectroscopy.The polydivinylbenzene-co-1-n-octyl-3-vinyl imidazole phosphotungstate(P(DVB-OVIm)PW)exhibited the highest DBT removal efficiency(99.9%)and remarkable recyclability,and could be reused eight times without reducing its activity.Finally,an extraction-free ODS mechanism is proposed. 展开更多
关键词 DESULFURIZATION polyionic liquids(PILs) cross-linking phosphotungstic acid oxidation reaction
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Free-radical evolution and decay in cross-linked polytetrafluoroethylene irradiated by gamma-rays 被引量:1
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作者 Fei-Xiang Sha Guo-Jun Cheng +4 位作者 Zi-Yue Xuan Yang Liu Wei-Hua Liu Xiao-Dong Zhang Zhong-Feng Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第5期113-125,共13页
Electron spin resonance techniques were employed to investigate the effects of the absorbed dose and post-irradiation conditions on the evolution and decay of free-radicals in cross-linked polytetrafluoroethylene(XPTF... Electron spin resonance techniques were employed to investigate the effects of the absorbed dose and post-irradiation conditions on the evolution and decay of free-radicals in cross-linked polytetrafluoroethylene(XPTFE),induced byγ-ray radiation.Chain-end free-radicals,chain alkyl free-radicals,and tertiary alkyl free-radicals were detected when XPTFE was irradiated under Ar atmosphere.The corresponding peroxy free-radicals were formed upon exposure of irradiated XPTFE to air;the freeradicals concentration first increased linearly with increasing absorbed dose and then gradually saturated.The free-radicals yield under air atmosphere was greater than that under Ar,and the peroxy free-radicals were preserved for a relatively long time when irradiated XPTFE was stored under air atmosphere.The chain alkyl free-radicals may be converted to chain end free-radicals byβ-scission,while chain end free-radicals are more sensitive to oxygen than chain alkyl free-radicals.When the annealing temperature was raised above the a-transition temperature of XPTFE,the decay of the free-radicals was greatly affected and accelerated by the motion of the molecules over the long range. 展开更多
关键词 Polytetrafluoroethylene cross-linked polytetrafluoroethylene Electron spinresonance DECAY Radiation c-ray
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Insights into the swelling process and drug release mechanisms from cross-linked pectin/high amylose starch matrices 被引量:1
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作者 Fernanda M.Carbinatto Ana Do´ris de Castro +1 位作者 Raul C.Evangelista Beatriz S.F.Cury 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2014年第1期27-34,共8页
Cross-linked pectin/high amylose mixtures were evaluated as a new excipient for matrix tablets formulations,since the mixing of polymers and cross-linking reaction represent rational tools to reach materials with modu... Cross-linked pectin/high amylose mixtures were evaluated as a new excipient for matrix tablets formulations,since the mixing of polymers and cross-linking reaction represent rational tools to reach materials with modulated and specific properties that meet specific therapeutic needs.Objective:In this work the influence of polymer ratio and cross-linking process on the swelling and the mechanism driving the drug release from swellable matrix tablets prepared with this excipient was investigated.Methods:Cross-linked samples were characterized by their micromeritic properties(size and shape,density,angle of repose and flow rate)and liquid uptake ability.Matrix tablets were evaluated according their physical properties and the drug release rates and mechanisms were also investigated.Results:Cross-linked samples demonstrated size homogeneity and irregular shape,with liquid uptake ability insensible to pH.Cross-linking process of samples allowed the control of drug release rates and the drug release mechanism was influenced by both polymer ratio and cross-linking process.The drug release of samples with minor proportion of pectin was driven by an anomalous transport and the increase of the pectin proportion contributed to the erosion of the matrix.Conclusion:The cross-linked mixtures of high amylose and pectin showed a suitable excipient for slowing the drug release rates. 展开更多
关键词 High amylose starch PECTIN cross-linking SWELLING Drug delivery mechanism
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In situ formed cross-linked polymer networks as dual-functional layers for high-stable lithium metal batteries 被引量:1
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作者 Lei Shi Wanhui Wang +7 位作者 Chunjuan Wang Yang Zhou Yuezhan Feng Tiekun Jia Fang Wang Zhiyu Min Ji Hu Zhigang Xue 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期253-262,共10页
Lithium-metal anodes(LMAs)have been recognized as the ultimate anodes for next-generation batteries with high energy density,but stringent assembly-environment conditions derived from the poor moisture stability drama... Lithium-metal anodes(LMAs)have been recognized as the ultimate anodes for next-generation batteries with high energy density,but stringent assembly-environment conditions derived from the poor moisture stability dramatically hinder the transformation of LMAs from laboratory to industry.Herein,an in situ formed cross-linked polymer layer on LMAs is designed and constructed by a facile thiol-acrylate click chemistry reaction between poly(ethylene glycol)diacrylate(PEGDA)and the crosslinker containing multi thiol groups under UV irradiation.Owing to the hydrophobic nature of the layer,the treated LMAs demonstrate remarkable humid stability for more than 3 h in ambient air(70%relative humidity).The coating humid-resistant protective layer also possesses a dual-functional characterization as solid polymer electrolytes by introducing lithium bis(trifluoromethanesulfonyl)imide in the system in advance.The intimate contact between the polymer layer and LMAs reduces interfacial resistance in the assembled Li/LiFePO_(4)or Li/LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)full cell effectively,and endows the cell with an outstanding cycle performance. 展开更多
关键词 Lithium-metal anode Humid-resistant protective film Solid-state polymer electrolytes cross-linked polymers
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Cross-linked polyelectrolyte reinforced SnO_(2)electron transport layer for robust flexible perovskite solar cells 被引量:1
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作者 Zhihao Li Zhi Wan +7 位作者 Chunmei Jia Meng Zhang Meihe Zhang Jiayi Xue Jianghua Shen Can Li Chao Zhang Zhen Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期335-342,I0010,共9页
SnO_(2)electron transport layer(ETL)is a vital component in perovskite solar cells(PSCs),due to its excellent photoelectric properties and facile fabrication process.In this study,we synthesized a water-soluble and ad... SnO_(2)electron transport layer(ETL)is a vital component in perovskite solar cells(PSCs),due to its excellent photoelectric properties and facile fabrication process.In this study,we synthesized a water-soluble and adhesive polyelectrolyte with ethanolamine(EA)and poly-acrylic acid(PAA).The linear PAA was crosslinked by EA,forming a 3D network that stabilized the SnO_(2)nanoparticle dispersion.An organic–inorganic hybrid ETL is developed by introducing the cross-linked PAA-EA into SnO_(2)ETL,which prevents nano particle agglomeration and facilitates uniform SnO_(2)film formation with fewer defects.Additionally,the PAA-EA-modified SnO_(2)facilitated a uniform and compact perovskite film,enhancing the interface contact and carrier transport.Consequently,the PAA-EA-modified PSCs exhibited excellent PCE of 24.34%and 22.88%with high reproducibility for areas of 0.045 and 1.00 cm~2,respectively.Notably,owing to structure reinforce effect of PAA-EA in SnO_(2)ETL,flexible device demonstrated an impressive PCE of 23.34%while maintaining 90.1%of the initial PCE after 10,000 bending cycles with a bending radius of 5 mm.This successful approach of polyelectrolyte reinforced hybrid organic–inorganic ETL displays great potential for flexible,large-area PSCs application. 展开更多
关键词 POLYELECTROLYTE cross-link Tin oxide Electron transfer layer Flexible solar cells
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A UV cross-linked gel polymer electrolyte enabling high-rate and high voltage window for quasi-solid-state supercapacitors 被引量:1
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作者 Yuge Bai Chao Yang +6 位作者 Boheng Yuan Hongjie Li Weimeng Chen Haosen Yin Bin Zhao Fei Shen Xiaogang Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期41-50,I0002,共11页
Serving as a promising alternative to liquid electrolyte in the application of portable and wearable devices,gel polymer electrolytes(GPEs)are expected to obtain more preferable properties rather than just be satisfie... Serving as a promising alternative to liquid electrolyte in the application of portable and wearable devices,gel polymer electrolytes(GPEs)are expected to obtain more preferable properties rather than just be satisfied with the merits of high safety and deformability.Here,an easy-operated method is employed to fabricate cross-linked composite polymer membranes used for GPEs assisted by UV irradiation,in which N-doped carbon quantum dots(N-CQDs)and TiO2are introduced as photocatalysts and additives to improve the performances of GPEs.Specifically,N-CQDs participate as a cross-linker to construct the inner porous structure,and TiO2nanoparticles serve as a stabilizer to improve the electrochemical stability of GPEs under high voltage(3.5 V).The excellent thermal and mechanical stability of the membrane fabricated in this work guarantee the safety of the supercapacitors(SCs).This GPE based SC not only exhibits prominent rate performance(105%capacitance retention at the current density of 40A g^(-1))and cyclic stability(85%at 1 A g^(-1)under 3.5 V after 20,000 cycles),but also displays remarkable energy density(42.88 Wh kg^(-1))with high power density(19.3 k W kg^(-1)).Moreover,the superior rate and cycling performances of the as-prepared GPE based flexible SCs under flat and bending state confirm the feasibility of its application in flexible energy storage devices. 展开更多
关键词 Gel polymer electrolyte UV cross-linking Energy density High voltage window
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