IET Nanodielectrics最新文献_第9页

Structure design boosts concomitant enhancement of permittivity, breakdown strength, discharged energy density and efficiency in all-organic dielectrics 结构设计提高了全有机电介质的介电常数、击穿强度、放电能量密度和效率

IF 2.7

IET Nanodielectrics Pub Date : 2020-12-02 DOI: 10.1049/iet-nde.2020.0034

Zhenkang Dan, Weibin Ren, Mengfan Guo, Zhonghui Shen, Tao Zhang, Jianyong Jiang, Cewen Nan, Yang Shen

{"title":"Structure design boosts concomitant enhancement of permittivity, breakdown strength, discharged energy density and efficiency in all-organic dielectrics","authors":"Zhenkang Dan, Weibin Ren, Mengfan Guo, Zhonghui Shen, Tao Zhang, Jianyong Jiang, Cewen Nan, Yang Shen","doi":"10.1049/iet-nde.2020.0034","DOIUrl":"10.1049/iet-nde.2020.0034","url":null,"abstract":"Polymer-based nanocomposites with excellent flexibility and intrinsic high breakdown strength are promising candidates for high energy density capacitors compared to ceramics counterparts. However, their energy density is relatively low due to the trade-off between permittivity and breakdown strength. In this work, the authors proposed a ferroconcrete-like structure for all-organic nanocomposites via combinatorial electrospinning and hot-pressing method. In this structure, polymethyl methacrylate (PMMA) serves as matrix while poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) serves as reinforcement phase. This novel structure is highly effective in breaking the paradox of improved discharged energy density with decreased efficiency, as evidenced by the concurrently improved discharged energy density (∼12.15 J/cm3 compared to 8.82 J/cm3 of the matrix) and efficiency (∼81.7% compared to 76.8% of the matrix). Compared to conventional blending composite films, samples with ferroconcrete-like structure exhibit higher permittivity, breakdown strength, discharged energy density and efficiency. The superior energy storage performance is attributed to large aspect ratio P(VDF-HFP) fibres distributed perpendicularly to the external field, which brings about the extra enhancement of permittivity. Besides, mechanical properties are improved and restriction on carrier motion is facilitated, leading to enhanced breakdown strength and suppressed conduction. This work provides a new way to design dielectric composite for high energy density and efficiency applications.","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"3 4","pages":"147-155"},"PeriodicalIF":2.7,"publicationDate":"2020-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/iet-nde.2020.0034","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42127845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Titania-based transformer nanofluid: a study on the synthesis for enhanced breakdown strength and its humidity ageing 钛酸基变压器纳米流体的合成及其湿老化研究

IF 2.7

IET Nanodielectrics Pub Date : 2020-11-12 DOI: 10.1049/iet-nde.2020.0014

S. Raja, G. Koperundevi

{"title":"Titania-based transformer nanofluid: a study on the synthesis for enhanced breakdown strength and its humidity ageing","authors":"S. Raja, G. Koperundevi","doi":"10.1049/iet-nde.2020.0014","DOIUrl":"10.1049/iet-nde.2020.0014","url":null,"abstract":"Researches on the transformer oil-based nanofluids to determine its suitability for replacing the conventional liquid insulation has been consistently happening for more than a decade. Yet, to prepare an optimum blend of transformer oil-based nanofluid with the stability compliance and superior breakdown (BD) characteristics is still a key issue to be addressed. So to achieve the higher BD voltages (BDVs) with good stability, the nanoparticle and surfactant weights dispersed in the oil should be optimised to at least possible critical levels. In this work, dielectric BD characteristic of mineral oil dispersed with TiO2 nanoparticle and surfactant cetyl trimethyl ammonium bromide (CTAB) is been studied with the applied AC and DC high voltages, which is termed as titania-based transformer nanofluid (TTNF) for this study. Series of TTNF samples were synthesised with different weights of TiO2 nanoparticle and CTAB, and the partial discharge inception voltage, AC and DC BDV were experimented to ascertain the optimum concentration level. Results show that the AC and DC BDV enhanced up to 36.23 and 43.07%, respectively, for the TTNF prepared with 0.00562 wt% of TiO2 and its 1% weight of CTAB, which was stable for around eight weeks.","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"3 4","pages":"138-146"},"PeriodicalIF":2.7,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/iet-nde.2020.0014","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44727443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

High-temperature dielectric properties and impedance spectroscopy of PbHf1−x Snx O3 ceramics phbhf1−x Sn x O 3陶瓷的高温介电性能和阻抗谱

IF 2.7

IET Nanodielectrics Pub Date : 2020-11-11 DOI: 10.1049/iet-nde.2020.0030

Zhi-Gang Liu, Peng-Zu Ge, Hui Tang, Xin-Gui Tang, Si-Ming Zeng, Yan-Ping Jiang, Zhen-Hua Tang, Qiu-Xiang Liu

{"title":"High-temperature dielectric properties and impedance spectroscopy of PbHf1−x Snx O3 ceramics","authors":"Zhi-Gang Liu, Peng-Zu Ge, Hui Tang, Xin-Gui Tang, Si-Ming Zeng, Yan-Ping Jiang, Zhen-Hua Tang, Qiu-Xiang Liu","doi":"10.1049/iet-nde.2020.0030","DOIUrl":"10.1049/iet-nde.2020.0030","url":null,"abstract":"PbHf1−x Snx O3 (PSH) ceramics were synthesised by a conventional solid-state reaction method. Dielectric properties were investigated in the temperature range of 20–650°C. As the Sn4+ content goes up, the phase transition temperatures of an antiferroelectric (AFE1) to another intermediate antiferroelectric (AFE2) phase and AFE2 to the paraelectric (PE) phase decrease gradually. When x ≥0.1 for PSH ceramics, the ferroelectric (FE) phase appears around 225°C, and phase transition temperature from FE phase to PE phase goes up with the increasing concentration of Sn4+. Moreover, high-temperature dielectric relaxation (HTDR) phenomenon can be seen from all samples. Mechanism of HTDR was discussed from impedance spectroscopy and conductivity for PSH ceramics. It was found that three dielectric responses were observed in complex impedance plots and HTDR was involved with the movement of oxygen vacancies. Activation energy calculated from dielectric data suggested that the HTDR was governed by the hopping conduction process.","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"3 4","pages":"131-137"},"PeriodicalIF":2.7,"publicationDate":"2020-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/iet-nde.2020.0030","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46588081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Liquid-phase preparation of BaTiO3 nanoparticles batio3纳米颗粒的液相制备

IF 2.7

IET Nanodielectrics Pub Date : 2020-10-30 DOI: 10.1049/iet-nde.2020.0021

Feng Shi, Huiling Chen, Jing Wang

{"title":"Liquid-phase preparation of BaTiO3 nanoparticles","authors":"Feng Shi, Huiling Chen, Jing Wang","doi":"10.1049/iet-nde.2020.0021","DOIUrl":"10.1049/iet-nde.2020.0021","url":null,"abstract":"Barium titanate (BaTiO3, BT) is widely used in the manufacture of electronic components such as multilayer ceramic capacitors, supercapacitors, thermistors, ferroelectric devices and piezoelectric devices due to its excellent dielectric, ferroelectric, piezoelectric and insulating properties. The performance of BT-based components is highly dependent on the quality of the BT nanoparticles. Large particle size and uneven distribution are the disadvantages of the BT nanoparticles synthesised by the traditional solid-phase reaction, however, the liquid-phase method can overcome these shortcomings, which has the characteristics of high purity and uniform composition with small particle size, and therefore is the main method for the preparation of BT nanoparticles. This review described various liquid-phase preparation methods of BT nanoparticles and compared the advantages and disadvantages of these methods, thereafter the optimised process parameters that affected the BT crystalline quality were summarised so as to obtain BT nanoparticles with a high crystalline quality, small particle size and even distribution.","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"3 4","pages":"107-115"},"PeriodicalIF":2.7,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/iet-nde.2020.0021","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44532472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Thermal ageing study of ZnO nanofluid–cellulose insulation 氧化锌纳米流体-纤维素绝热老化研究

IF 2.7

IET Nanodielectrics Pub Date : 2020-10-28 DOI: 10.1049/iet-nde.2020.0018

Asmaa Ibrahim, Loai Nasrat, Ahmed Elnoby, Soliman Eldebeiky

{"title":"Thermal ageing study of ZnO nanofluid–cellulose insulation","authors":"Asmaa Ibrahim, Loai Nasrat, Ahmed Elnoby, Soliman Eldebeiky","doi":"10.1049/iet-nde.2020.0018","DOIUrl":"10.1049/iet-nde.2020.0018","url":null,"abstract":"Trends in the studies of mineral oil (MO)-based nanofluids (NFs) show that most of the conducted works have focused only on the thermal and dielectric properties but few numbers on the ageing performance. In the present study, ZnO NF, in combination with cellulose insulation experienced accelerated thermal ageing at 120 °C for 20 days to study the ageing performance and it was compared with that of MO–cellulose insulation. The deterioration rate of cellulose was evaluated through tensile strength, breakdown voltage (BDV) and dielectric dissipation factor properties. Whereas oils deterioration was evaluated through BDV, interfacial tension, kinematic viscosity, acidity and colour. The results demonstrate that for cellulose aged in NF (NFIP), the tensile strength and BDV are 3 and 6.9% higher, respectively; than those aged in MO. For aged oils, NF exhibits higher values of the viscosity and acidity by 3 and 33.3%, respectively, than MO. The BDV of NF is superior to that of MO in the initial ageing period, after that; it shows a lesser reduction tendency with ageing. The most important observation from this study is that despite this increment of ageing indicators for NF, it could improve the anti-ageing properties of cellulose insulation.","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"3 4","pages":"124-130"},"PeriodicalIF":2.7,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/iet-nde.2020.0018","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47300890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Investigations on the effect of ageing on charge de-trapping processes of epoxy–alumina nanocomposites based on isothermal relaxation current measurements 老化对环氧-氧化铝纳米复合材料电荷脱陷过程影响的等温弛豫电流测量研究

IF 2.7

IET Nanodielectrics Pub Date : 2020-10-13 DOI: 10.1049/iet-nde.2020.0020

Subhajit Maur, Nasirul Haque, Preetha Pottekat, Biswajit Chakraborty, Sovan Dalai, Biswendu Chatterjee

{"title":"Investigations on the effect of ageing on charge de-trapping processes of epoxy–alumina nanocomposites based on isothermal relaxation current measurements","authors":"Subhajit Maur, Nasirul Haque, Preetha Pottekat, Biswajit Chakraborty, Sovan Dalai, Biswendu Chatterjee","doi":"10.1049/iet-nde.2020.0020","DOIUrl":"10.1049/iet-nde.2020.0020","url":null,"abstract":"In this study, the relationship between thermal ageing and charge trapping properties of epoxy-based nanocomposites has been investigated. With ageing, any dielectric material undergoes thorough degradation. This degradation significantly affects the space charge accumulation and charge trapping behaviour of the dielectric, which are very important parameters for insulation health under high-voltage direct current (HVDC) environment. In this work, an improved model based on the isothermal relaxation current (IRC) has been developed to study the charge trapping behaviour of pure epoxy and epoxy alumina (Al2 O3) nano-composites at different ageing conditions. A methodology based on polarisation–depolarisation current (PDC) measurements has been proposed to identify the current component due to a dipolar relaxation in measured total IRC. This will help to identify the trap distribution characteristics more accurately compared to conventional IRC measurements. It was experimentally observed that the addition of nanoparticles significantly reduces trapped charge formation and reduces thermal degradation. It is observed that aging leads to the generation of deeper traps, while the addition of Al2 O3 nanoparticles mainly enhances the density of shallow traps. Results presented in this work indicate that epoxy–alumina nanocomposites are very much suitable in HVDC applications from the perspective of trapped charge accumulation.","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"3 4","pages":"116-123"},"PeriodicalIF":2.7,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/iet-nde.2020.0020","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45725483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Review of dielectric elastomers for actuators, generators and sensors 致动器、发电机和传感器用电介质弹性体综述

IF 2.7

IET Nanodielectrics Pub Date : 2020-09-03 DOI: 10.1049/iet-nde.2019.0045

Yu Zhao, Li-Juan Yin, Shao-Long Zhong, Jun-Wei Zha, Zhi-Min Dang

引用次数: 28

Improved dielectric properties of PVDF nanocomposites with core–shell structured BaTiO3 @polyurethane nanoparticles 核壳结构batio3 @聚氨酯纳米颗粒改善PVDF纳米复合材料介电性能

IF 2.7

IET Nanodielectrics Pub Date : 2020-09-01 DOI: 10.1049/iet-nde.2020.0015

Ming-Sheng Zheng, Chong Zhang, Yu Yang, Zhao-Liang Xing, Xin Chen, Shao-Long Zhong, Zhi-Min Dang

{"title":"Improved dielectric properties of PVDF nanocomposites with core–shell structured BaTiO3 @polyurethane nanoparticles","authors":"Ming-Sheng Zheng, Chong Zhang, Yu Yang, Zhao-Liang Xing, Xin Chen, Shao-Long Zhong, Zhi-Min Dang","doi":"10.1049/iet-nde.2020.0015","DOIUrl":"10.1049/iet-nde.2020.0015","url":null,"abstract":"<div>\u0000 Polymer nanocomposites with improved dielectric permittivity and high breakdown strength are extremely desirable for the flexible electronic devices and power systems. The compatibility of fillers and polymer matrix is important in determining the dielectric and breakdown strength properties. The core–shell structure concept is useful to improve the compatibility of fillers with polymer matrix. Herein, an organic thermoplastic urethanes (TPU) polymer shell was successfully grafted on the surface of barium titanate (BaTiO3, BT) and such a TPU shell improved the permittivity and breakdown strength of TPU@BT/PVDF polymer nanocomposites greatly. The permittivity of TPU@BT/PVDF nanocomposites with 12 wt% fillers at 102 Hz was up to 13.5, which was 1.5 times higher than that of pure poly(vinylidene fluoride) (PVDF). The improvement of the dielectric properties could be attributed to the enhanced interfacial polarisation between BT nanoparticles and TPU shell. Besides, the compatibility of BT nanoparticles and PVDF matrix was improved after the introduction of TPU shell. Accordingly, a highest breakdown strength value about 373 MV/m was obtained for the TPU@BT/PVDF nanocomposites with 7 wt% fillers. The core–shell strategy could be extended to a variety of inorganic fillers to improve the dielectric and breakdown strength properties of polymer nanocomposites.\u0000 </div>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"3 3","pages":"94-98"},"PeriodicalIF":2.7,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/iet-nde.2020.0015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45507533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 28

Evaluation of dielectric strength of SiR/TiO2 composites using feed-forward neural network 用前馈神经网络评价SiR/ tio2复合材料的介电强度

IF 2.7

IET Nanodielectrics Pub Date : 2020-07-06 DOI: 10.1049/iet-nde.2020.0001

Shaymaa A. Qenawy, Loai S. Nasrat, Hanafy M. Ismail, Jeannette N. Asaad

{"title":"Evaluation of dielectric strength of SiR/TiO2 composites using feed-forward neural network","authors":"Shaymaa A. Qenawy, Loai S. Nasrat, Hanafy M. Ismail, Jeannette N. Asaad","doi":"10.1049/iet-nde.2020.0001","DOIUrl":"10.1049/iet-nde.2020.0001","url":null,"abstract":"<div>\u0000 Among the recently insulating materials broadly utilized in high voltage outdoor insulation, silicone rubber (SiR) has gotten the foremost consideration. Actually, SiR is becoming an efficient countermeasure to insulator contamination issues. To enhance different properties of polymeric materials, micro- and nanofillers have been used for dielectric applications. In this study, micron-sized titanium dioxide (TiO2) and nano-sized TiO2 fillers were added to the SiR matrix to improve electrical and mechanical properties. Dielectric strength, tensile strength, and elongation at break tests were monitored. Also, a scanning electron microscope was carried out. The samples were prepared by mixing micro-TiO2 into SiR with the content of 0, 10, 20, 30, and 40 wt% and also mixing nano-TiO2 into SiR with the content of 0, 1, 3, 5, and 7 wt%. A feed-forward neural network technique was used to estimate the dielectric strength in different conditions and different percentages of fillers. Adding nano TiO2 filler enhances the electrical and mechanical properties of SiR composites. SiR with 5 wt% nano TiO2 showed the best improvement in electrical and mechanical properties.\u0000 </div>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"3 3","pages":"74-80"},"PeriodicalIF":2.7,"publicationDate":"2020-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1049/iet-nde.2020.0001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47932191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Charge trapped mechanism for semi-crystalline polymer electrets: quasi-dipole model 半结晶聚合物驻极体的电荷捕获机制:准偶极子模型

IF 2.7

IET Nanodielectrics Pub Date : 2020-07-03 DOI: 10.1049/iet-nde.2020.0003

Gangjin Chen, Jianfeng Zhang, Xiaoyan Shi, Huili Peng, Xi Chen

{"title":"Charge trapped mechanism for semi-crystalline polymer electrets: quasi-dipole model","authors":"Gangjin Chen, Jianfeng Zhang, Xiaoyan Shi, Huili Peng, Xi Chen","doi":"10.1049/iet-nde.2020.0003","DOIUrl":"10.1049/iet-nde.2020.0003","url":null,"abstract":"<div>\u0000 Polymer electrets are increasingly getting application in a very wide range. However, its charge trapped mechanism is still poorly understood. It is always challenging how to improve its charge trapped ability and to enhance its performance stability. In this study, a charge trapped mechanism, quasi-dipole model, is proposed for semi-crystalline polymer electrets. Every grain of crystallite is viewed as a dipole based on the polarisation effect between crystalline and amorphous region when charged. The energy level of the charge trap has a dependence on the crystallite structure. The more regular the crystallite grain structure the better charge stability is. The melt-blown polypropylene (MBPP) electret fabrics with α or mesomorphic crystallite are used as the model material to verify the rationality of the mechanism. The experiment results from thermally stimulating discharge and X-ray diffraction proved that the charge-trapped stability could be improved by means of transformation from meso-crystalline to α crystalline structure. The MBPP fabric containing α-crystallite shows much better charge trapped performance than one containing mesomorphic-crystallite because of more regular structure in α crystallite. The findings not only present new insight into charge-trapped phenomena in polymer electrets, but also provide innovation for the processing technology of polymer electret materials.\u0000 </div>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"3 3","pages":"81-87"},"PeriodicalIF":2.7,"publicationDate":"2020-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/iet-nde.2020.0003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47263307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6