Pub Date : 2020-08-15DOI: 10.2115/fiberst.2020-0028
Takuo Hashidume, S. Takemura, Q. Ni
近年,地球温暖化および資源の枯渇などの地球環境 問題が深刻となっており,地球環境問題への取り組み が世界的に行われている.特に航空宇宙および自動車 産業を代表とする輸送機器からの排気ガスが問題と なっており,省エネルギの観点から軽量化が必要とさ れている.そこで,軽量高強度の複合材料が期待され ている.その中でも,カーボン繊維強化プラスチック ス(Carbon Fiber reinforced Plastics: CFRP)は,金属 Abstract: The purpose of this study is to design a hybrid CFRP structure using pitch-based carbon fiber and PAN-based carbon fiber, and to develop an optimal hybrid CFRP structure. Various cross-laminated hybrid CFRP structures were fabricated, and the composition and arrangement of pitch-based and PAN-based carbon fibers were changed. The developed CFRP structures were investigated by bending and impact measurements. As a result, the following findings were obtained. The results of the mechanical properties of three-point bending showed that it was possible to obtain higher bending strength than the individual pitch-based or PAN-based CFRP structure by hybridizing. The hybrid CFRP structure with 20% pitch-based carbon fiber in the outermost layer and 80% PAN-based carbon fiber in the core layer shows higher flexural strength, flexure and fracture initiation energy than PAN-based 100% CFRP. It was confirmed that the reinforcement effect of the hybrid of pitch type and PAN type CFRP was remarkable with the synergistic effect of both carbon fibers. From the dynamic mechanical properties by the impact test, a hybrid CFRP structural material with PAN-based carbon fiber 60% in the outermost layer and pitch-based carbon fiber 40% in the core layer, the residual strength after maximum load and the total absorbed energy are greatly improved. Ultrasonic testing shows that pitch-based carbon fibers are arranged in the outermost layer, which reduces delamination and improves internal damage resistance, and supports the hybrid reinforcing effect of pitch-based and PAN-based CFRP. All of these results indicated it is possible to improve the static and dynamic mechanical performance and optimize the material structure by designing the ratio of the pitch-based carbon fiber and the PAN-based carbon fiber and the arrangement in the thickness direction of CFRP structures, which may help in the future CFRP structural design. (Received 22 March, 2020; Accepted 11 May, 2020)
近年来，全球变暖及资源枯竭等全球环境问题日益严重，全球范围内都在采取措施解决全球环境问题。特别是以航空宇宙和汽车产业为代表的运输设备产生的废气问题，从节约能源的角度考虑，需要轻量化。因此，期待轻量高强度复合材料的出现。其中，碳纤维增强塑料(Carbon Fiber reinforced Plastics, CFRP)是金属Abstract:The purpose of this study is to design a hybrid CFRP structure using pitch-based carbon光纤andPAN-based碳光纤，与develop an optimal hybrid CFRP structure. Various cross-laminated hybrid CFRP structures werefabricated,and the composition and arrangement of pitch-based and PAN-based carbon fibers were changed. thedeveloped CFRP structures were investigated by bending and impact measurements. As a result，the following findings were obtained. the results of the mechanical properties of three-pointbending showed that it was possible to obtain higher bending strength than the individualpitch-based or PAN-based CFRP structure by hybridizing. The hybrid CFRP structure with 20%pitch-based carbon光纤in the outermost layer and 80% PAN-based carbon光纤in the core layershows higher flexural strength，flexure and fracture initiation energy than PAN-based 100% CFRP. It was confirmed that thereinforcement effect of the hybrid of pitch type and PAN type CFRP was remarkable with thesynergistic effect of both carbon fibers. From the dynamic mechanical properties by the impact test，hybrid CFRP structural material with PAN-based carbon fiber 60% in the outermost layer andpitch-based carbon光纤40% in the core layer，the residual strength after maximum load and the total absorbed energy are greatly improved.Ultrasonic testing shows that pitch-based carbon fibers are arranged in the outermost layer，which reduces delamination and improves internal damage resistance，hybrid reinforcing effect of pitch-based and PAN-based CFRP. All of these resultsdicated it is possible to improve the static and dynamic mechanical performance and optimize thematerial structure by设计the ratio of the pitch-based carbon fiber and the PAN-based carbonfiber and the arrangement in the thickness direction of CFRP structures，which may help in the future CFRP structural design. (Received 22 March, 2020;Accepted 11 May, 2020)
{"title":"Structural Design of Hybrid CFRP Using Pitch-Based and PAN-Based Carbon Fibers and Their Mechanical Properties","authors":"Takuo Hashidume, S. Takemura, Q. Ni","doi":"10.2115/fiberst.2020-0028","DOIUrl":"https://doi.org/10.2115/fiberst.2020-0028","url":null,"abstract":"近年,地球温暖化および資源の枯渇などの地球環境 問題が深刻となっており,地球環境問題への取り組み が世界的に行われている.特に航空宇宙および自動車 産業を代表とする輸送機器からの排気ガスが問題と なっており,省エネルギの観点から軽量化が必要とさ れている.そこで,軽量高強度の複合材料が期待され ている.その中でも,カーボン繊維強化プラスチック ス(Carbon Fiber reinforced Plastics: CFRP)は,金属 Abstract: The purpose of this study is to design a hybrid CFRP structure using pitch-based carbon fiber and PAN-based carbon fiber, and to develop an optimal hybrid CFRP structure. Various cross-laminated hybrid CFRP structures were fabricated, and the composition and arrangement of pitch-based and PAN-based carbon fibers were changed. The developed CFRP structures were investigated by bending and impact measurements. As a result, the following findings were obtained. The results of the mechanical properties of three-point bending showed that it was possible to obtain higher bending strength than the individual pitch-based or PAN-based CFRP structure by hybridizing. The hybrid CFRP structure with 20% pitch-based carbon fiber in the outermost layer and 80% PAN-based carbon fiber in the core layer shows higher flexural strength, flexure and fracture initiation energy than PAN-based 100% CFRP. It was confirmed that the reinforcement effect of the hybrid of pitch type and PAN type CFRP was remarkable with the synergistic effect of both carbon fibers. From the dynamic mechanical properties by the impact test, a hybrid CFRP structural material with PAN-based carbon fiber 60% in the outermost layer and pitch-based carbon fiber 40% in the core layer, the residual strength after maximum load and the total absorbed energy are greatly improved. Ultrasonic testing shows that pitch-based carbon fibers are arranged in the outermost layer, which reduces delamination and improves internal damage resistance, and supports the hybrid reinforcing effect of pitch-based and PAN-based CFRP. All of these results indicated it is possible to improve the static and dynamic mechanical performance and optimize the material structure by designing the ratio of the pitch-based carbon fiber and the PAN-based carbon fiber and the arrangement in the thickness direction of CFRP structures, which may help in the future CFRP structural design. (Received 22 March, 2020; Accepted 11 May, 2020)","PeriodicalId":54299,"journal":{"name":"Journal of Fiber Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41254109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-15DOI: 10.2115/fiberst.2020-0020
E. Shoji
Long cellulose nanofibers and shorter rod-shaped cellulose nanocrystals are generally referred to as nanocellulose. They exhibit hierarchical structures with a width of 2‒20 nm and are included in native celluloses originating from plants. Nanofibers have been extensively investigated for various applications because of their unique structural properties, nanoscale effects, and large surface area[1, 2]. During the development of cellulose nanofibers, obtaining fine and long fibers is necessary to introduce advanced features into such natural materials. Fine cellulose nanofibers can be prepared by the mechanical disintegration of natural fibers after appropriate pretreatments. Cellulose nanofibers can be prepared using various methods, including enzymatic[3], mechanochemical[4], oxidation[5, 6], or esterification[7]. 2,2,6,6 tetramethyl piperidinyl 1 oxyl radical (TEMPO) is a stable radical that mediates the oxidation from primary alcohols to the carboxylic acid groups. Cellulose nanofibers can be obtained by defibrating the cellulose fiber aggregates using TEMPO[8, 9]. During cellulose defibration by oxidation with TEMPO at room temperature when the pH is approximately 10, the C6 primary hydroxyls of nanocellulose are selectively converted to the C6 carboxylate groups[10]. Therefore, TEMPO-mediated oxidation is the key to disperse the nanofiber surfaces of the cellulose and polyelectrolyte structures of the carboxylate groups[11, 12]. Conducting fabrics are attractive fiber-based materials that can be used to suppress the electromagnetic interference from electronic devices [13‒16]. Compared with conventional metal-based mesh materials, conducting fabrics are more flexible and lightweight[13‒16]. Polymer actuators have recently attracted considerable attention owing to their unique features and the possibility of them being used to develop mechanical energy transducers for producing direct bending and stretching motions as an alternative technology to electric motors[17‒19]. For example, the ionic polymer metal composites (IPMCs) have exhibited an excellent performance, providing large bending displacements at applied potentials of only a few volts[20‒22]. An electroless plating method was used to introduce electrodes onto both sides of a polyelectrolyte film. Instead of using electroless plating methods, polymer actuators can be fabricated 【SPECIAL EDITIONS on Annual Meeting-Rapid Communication】
{"title":"Fabrication of Cellulose Nanofiber Actuators by One-Step Adhesion of the Conducting Fabric Electrodes","authors":"E. Shoji","doi":"10.2115/fiberst.2020-0020","DOIUrl":"https://doi.org/10.2115/fiberst.2020-0020","url":null,"abstract":"Long cellulose nanofibers and shorter rod-shaped cellulose nanocrystals are generally referred to as nanocellulose. They exhibit hierarchical structures with a width of 2‒20 nm and are included in native celluloses originating from plants. Nanofibers have been extensively investigated for various applications because of their unique structural properties, nanoscale effects, and large surface area[1, 2]. During the development of cellulose nanofibers, obtaining fine and long fibers is necessary to introduce advanced features into such natural materials. Fine cellulose nanofibers can be prepared by the mechanical disintegration of natural fibers after appropriate pretreatments. Cellulose nanofibers can be prepared using various methods, including enzymatic[3], mechanochemical[4], oxidation[5, 6], or esterification[7]. 2,2,6,6 tetramethyl piperidinyl 1 oxyl radical (TEMPO) is a stable radical that mediates the oxidation from primary alcohols to the carboxylic acid groups. Cellulose nanofibers can be obtained by defibrating the cellulose fiber aggregates using TEMPO[8, 9]. During cellulose defibration by oxidation with TEMPO at room temperature when the pH is approximately 10, the C6 primary hydroxyls of nanocellulose are selectively converted to the C6 carboxylate groups[10]. Therefore, TEMPO-mediated oxidation is the key to disperse the nanofiber surfaces of the cellulose and polyelectrolyte structures of the carboxylate groups[11, 12]. Conducting fabrics are attractive fiber-based materials that can be used to suppress the electromagnetic interference from electronic devices [13‒16]. Compared with conventional metal-based mesh materials, conducting fabrics are more flexible and lightweight[13‒16]. Polymer actuators have recently attracted considerable attention owing to their unique features and the possibility of them being used to develop mechanical energy transducers for producing direct bending and stretching motions as an alternative technology to electric motors[17‒19]. For example, the ionic polymer metal composites (IPMCs) have exhibited an excellent performance, providing large bending displacements at applied potentials of only a few volts[20‒22]. An electroless plating method was used to introduce electrodes onto both sides of a polyelectrolyte film. Instead of using electroless plating methods, polymer actuators can be fabricated 【SPECIAL EDITIONS on Annual Meeting-Rapid Communication】","PeriodicalId":54299,"journal":{"name":"Journal of Fiber Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42433741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-15DOI: 10.2115/fiberst.2020-0025
Takumi Yoshida, M. Segi
ポリプロピレン(PP)は汎用樹脂の中で比重が最も 小さく,耐熱性,剛性に優れ,また透明性,耐水性, 耐薬品性,絶縁性が良好である.これらの優れた特性 から PP は自動車,フィルム,シート,雑貨,家電, 医療機器,繊維など様々な分野で利用されている. 特に,PP 繊維が開発された当初はその有用性から 夢の繊維とまで言われ,様々な応用が期待された.し かしながら,現在,繊維としての主な用途は,アンダー ウェア,カーペット,ロープ,ビジネスソックス,産 業資材等に限られ,アパレル分野での利用は少なく未 だ夢は夢のままである[1]. このアパレル分野における PP 繊維の利用の少なさ は,PP 繊維の染色性の悪さに起因するところが大き い[2].つまり,PP 繊維はその単純な分子構造のた めに染着座席をまったく持たず,染色性に乏しいこと から,ファッション性の高い服地への利用は難しいの である. それゆえに,この様々な有用性を持ちながらも,染 色性に乏しい PP 繊維をアパレル分野で利用するため の染色研究は,世界中で 50 年以上実施されている. 例えば,樹脂の製造時に顔料を混練する方法(原着), PP 繊維に染色可能な部材や官能基を導入する方法 [3],超臨界流体を用いて染料を繊維内部に浸透させ る方法[4],繊維の表面を電子線で改質する方法[5] などである.しかしながら,原着では色の種類の不足, 染色可能な部材の導入では物性の変化による PP の良 Abstract: Polypropylene (PP) fibers have various excellent characteristics. However, it is difficult to use PP fibers for fashionable apparels due to its poor dyeing properties. Hence, in this paper, it has studied that developing a novel simple and inexpensive dyeing method for PP fibers by utilizing a cationic dye. It was developed that the PP dyeing method with the reduced form of a cationic dye, namely, leuco form. In the method, the permeability and affinity of the cationic dye for PP fibers would have been enhanced by reducing the cationic dye treated with a reducing agent in the alkaline aqueous solution. As a result, the reduced form of the cationic dye was adsorbed onto the PP fibers. Although, the color of the dye disappeared under an alkaline condition, the adsorbed cationic dye was recolored and fixed by treating with an oxidizing agent, and the dyed PP fibers were obtained. Following aforesaid method, the dyed PP fabrics were obtained by reducing the cationic dye with glucose under an alkaline condition at 100 ̊C and oxidizing it in an aqueous acetic acid solution at 50 ̊C. It was found that the L* of the dyed fabrics were low when Basic Blue 3, Basic Red 2, Basic Yellow 7, and Basic Orange 14 were used as a cationic dye. (Received 17 November, 2019; Accepted 1 April, 2020)
聚丙烯(PP)在通用树脂中比重最小，具有良好的耐热性和刚度，而且具有透明性、耐水性、由于具有良好的耐化学性能和绝缘性，PP被广泛应用于汽车、薄膜、薄膜、杂货、家电、医疗器械、纤维等各种领域。特别是PP纤维刚被开发出来的时候，因其实用性而被称为梦幻纤维，在各种各样的应用上都备受期待。但是，目前作为纤维的主要用途是生产运动服、地毯、绳索、商务袜等。仅限于工业材料等，在服装领域的应用较少，至今仍是梦幻。[1]. PP纤维在服装领域的应用较少，主要是因为PP纤维的染色性较差。意[2].也就是说，PP纤维由于分子结构简单，完全不具有染色座席，染色性差，所以很难用于时尚性高的面料。因此，为了在服装领域利用这种具有多种实用性，但染色性较差的PP纤维，全世界已经开展了50多年的染色研究。例如，制造树脂时混合颜料的方法(原着);在PP纤维中导入可染色构件和官能团的方法[3]，使用超临界流体使染料渗透到纤维内部的方法[4]，用电子线对纤维表面进行改性的方法[5]但是，由于原着的颜色种类不足，由于可染色部件的引入物性的变化导致PP的良Abstract:Polypropylene (PP) fibers have various excellent characteristics. However，it is difficult to use PP fibers for fashionable apparels due to its poor dyeing properties. Hence，in this paper，it has studied that developing a novel simple and inexpensive dyeing method for PP fibers byutilizing a cationic dye. It was developed that the PP dyeing method with the reduced form of acationic dye, namely, leuco form. In the method，the permeability and affinity of the cationic dye for PP fibers would have been增强by reducingthe cationic dye treated with a reducing agent in the alkaline aqueous solution. As a resultthe reduced form of the cationic dye was adsorbed onto the PP fibers. Although，the color of the dye disappeared under an alkaline condition，the adsorbed cationic dye was recolored and fixed by treating with an oxidizing agent，and the dyed PP fibers were obtained. Following aforesaid method，the dyed PP fabrics were obtained by reducing the cationic dye with glucose under an alkalinecondition at 100 c and̊oxidizing it in an aqueous acetic acid solution at 50̊c . it was found thatthe L* of the dyed fabrics were low when Basic Blue 3, Basic Red 2, Basic Yellow 7，and Basic Orange 14 were used as a cationic dye. (Received 17 November, 2019;Accepted 1 April, 2020)
{"title":"Novel Dyeing Method for Polypropylene Fiber via Reduction and Oxidation Processes of Cationic Dye","authors":"Takumi Yoshida, M. Segi","doi":"10.2115/fiberst.2020-0025","DOIUrl":"https://doi.org/10.2115/fiberst.2020-0025","url":null,"abstract":"ポリプロピレン(PP)は汎用樹脂の中で比重が最も 小さく,耐熱性,剛性に優れ,また透明性,耐水性, 耐薬品性,絶縁性が良好である.これらの優れた特性 から PP は自動車,フィルム,シート,雑貨,家電, 医療機器,繊維など様々な分野で利用されている. 特に,PP 繊維が開発された当初はその有用性から 夢の繊維とまで言われ,様々な応用が期待された.し かしながら,現在,繊維としての主な用途は,アンダー ウェア,カーペット,ロープ,ビジネスソックス,産 業資材等に限られ,アパレル分野での利用は少なく未 だ夢は夢のままである[1]. このアパレル分野における PP 繊維の利用の少なさ は,PP 繊維の染色性の悪さに起因するところが大き い[2].つまり,PP 繊維はその単純な分子構造のた めに染着座席をまったく持たず,染色性に乏しいこと から,ファッション性の高い服地への利用は難しいの である. それゆえに,この様々な有用性を持ちながらも,染 色性に乏しい PP 繊維をアパレル分野で利用するため の染色研究は,世界中で 50 年以上実施されている. 例えば,樹脂の製造時に顔料を混練する方法(原着), PP 繊維に染色可能な部材や官能基を導入する方法 [3],超臨界流体を用いて染料を繊維内部に浸透させ る方法[4],繊維の表面を電子線で改質する方法[5] などである.しかしながら,原着では色の種類の不足, 染色可能な部材の導入では物性の変化による PP の良 Abstract: Polypropylene (PP) fibers have various excellent characteristics. However, it is difficult to use PP fibers for fashionable apparels due to its poor dyeing properties. Hence, in this paper, it has studied that developing a novel simple and inexpensive dyeing method for PP fibers by utilizing a cationic dye. It was developed that the PP dyeing method with the reduced form of a cationic dye, namely, leuco form. In the method, the permeability and affinity of the cationic dye for PP fibers would have been enhanced by reducing the cationic dye treated with a reducing agent in the alkaline aqueous solution. As a result, the reduced form of the cationic dye was adsorbed onto the PP fibers. Although, the color of the dye disappeared under an alkaline condition, the adsorbed cationic dye was recolored and fixed by treating with an oxidizing agent, and the dyed PP fibers were obtained. Following aforesaid method, the dyed PP fabrics were obtained by reducing the cationic dye with glucose under an alkaline condition at 100 ̊C and oxidizing it in an aqueous acetic acid solution at 50 ̊C. It was found that the L* of the dyed fabrics were low when Basic Blue 3, Basic Red 2, Basic Yellow 7, and Basic Orange 14 were used as a cationic dye. (Received 17 November, 2019; Accepted 1 April, 2020)","PeriodicalId":54299,"journal":{"name":"Journal of Fiber Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67638929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-15DOI: 10.2115/fiberst.2020-0021
M. Tada, Iwataro-Yasuhiro Oka, Kuniko Matsunashi, N. Kida, A. Goto, N. Kuwahara
: In Japan, there are braids attached to the scrolls of valuable cultural assets. During the future replication of these braids over several generations, they should be fabricated considering their cultural significance. Thus far, the quality of braid replication has primarily depended on the skill level of braid experts and there is limited systematic research on the replication of braids based on their original use. To facilitate consistent replication of the braids attached to the scrolls of cultural assets, it is necessary to rediscover braid replication techniques and reorganize the process as objective knowledge. In this study, the effect of differences in the braided yarn angle and the bobbin mass of Taka-dai on the appearance and physical properties were investigated and statistically analyzed for the production of flat braids attached to scrolls. It was established that the difference in the applied tension to the braiding point during production caused by the balance between angle and bobbin mass affected the appearance of the braids and their physical properties. Because the appearance and mechanical properties affect not only practical performance, but also ridge arrangement exposed on the braid surface and design, a balance between the choice of an appropriate angle and bobbin mass is important. Based on this research, it is likely that useful knowledge will be obtained during the process of replicating the braids of cultural property scrolls without relying on skilled workers in the future.
{"title":"Effects of Braid Production for Scrolls on Appearance and Mechanical Properties","authors":"M. Tada, Iwataro-Yasuhiro Oka, Kuniko Matsunashi, N. Kida, A. Goto, N. Kuwahara","doi":"10.2115/fiberst.2020-0021","DOIUrl":"https://doi.org/10.2115/fiberst.2020-0021","url":null,"abstract":": In Japan, there are braids attached to the scrolls of valuable cultural assets. During the future replication of these braids over several generations, they should be fabricated considering their cultural significance. Thus far, the quality of braid replication has primarily depended on the skill level of braid experts and there is limited systematic research on the replication of braids based on their original use. To facilitate consistent replication of the braids attached to the scrolls of cultural assets, it is necessary to rediscover braid replication techniques and reorganize the process as objective knowledge. In this study, the effect of differences in the braided yarn angle and the bobbin mass of Taka-dai on the appearance and physical properties were investigated and statistically analyzed for the production of flat braids attached to scrolls. It was established that the difference in the applied tension to the braiding point during production caused by the balance between angle and bobbin mass affected the appearance of the braids and their physical properties. Because the appearance and mechanical properties affect not only practical performance, but also ridge arrangement exposed on the braid surface and design, a balance between the choice of an appropriate angle and bobbin mass is important. Based on this research, it is likely that useful knowledge will be obtained during the process of replicating the braids of cultural property scrolls without relying on skilled workers in the future.","PeriodicalId":54299,"journal":{"name":"Journal of Fiber Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43446682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-15DOI: 10.2115/fiberst.2020-0022
Shao Weili, Yue Wanli, Gaihuan Ren, L. Fan, Li Fang, Weng Kai, Li Mengying, Chen Yuankun, Lu Tong, Xiong Junpeng, Bu Wanjun, Wang Lidan, Jianxin He
: With the rapid development of industrialization, the problem of air pollution is becoming more and more serious. The haze with PM 2.5 as the main component is the most harmful one, which is very harmful to the human respiratory system. People use a variety of methods to protect their living environment, among which the nanometer fiber anti-haze window screen is a very effective protective material. However, due to the rapid aging of the functional layer of nanofilaments after the previous exposure to the sunlight, its service life can be shortened, and the practical value of the products will be reduced. We added a composite anti-aging agent (UV 1/AN-1135) into the spinning solution to prepare polyurethane (PU) anti-aging nanofibers to improve the anti-aging properties of the prepared nanofibers and modified the contents of different UV 1/AN-1135. The structure and properties of the PU nanofiber membrane were characterized and analyzed. The results showed that the addition of UV 1/AN-1135 improved the anti-aging properties of PU nanofibers. When the UV 1/AN-1135 content is 1 wt%, the fiber membrane can absorb most of the ultraviolet rays, and the nanofibers have the smallest diameter (135.97 nm). The most uniform is that the transmittance of the fiber film is above 80% and the gas permeability test result is greater than 800 mm/s. After UV aging treatment, the fiber membrane with UV 1/AN-1135 content of 1 wt% still maintains the highest tensile strength (after aging: breaking strength 21.61 MPa, breaking elongation 115.04%) and optimal filtration performance (after aging: the efficiency is 96.925%, the filtration resistance is 30.66 Pa, and the quality factor is 0.1136).
{"title":"Preparation of UV-Resistant TPU Nanofiber and Its Application in Anti-Haze Window Screening","authors":"Shao Weili, Yue Wanli, Gaihuan Ren, L. Fan, Li Fang, Weng Kai, Li Mengying, Chen Yuankun, Lu Tong, Xiong Junpeng, Bu Wanjun, Wang Lidan, Jianxin He","doi":"10.2115/fiberst.2020-0022","DOIUrl":"https://doi.org/10.2115/fiberst.2020-0022","url":null,"abstract":": With the rapid development of industrialization, the problem of air pollution is becoming more and more serious. The haze with PM 2.5 as the main component is the most harmful one, which is very harmful to the human respiratory system. People use a variety of methods to protect their living environment, among which the nanometer fiber anti-haze window screen is a very effective protective material. However, due to the rapid aging of the functional layer of nanofilaments after the previous exposure to the sunlight, its service life can be shortened, and the practical value of the products will be reduced. We added a composite anti-aging agent (UV 1/AN-1135) into the spinning solution to prepare polyurethane (PU) anti-aging nanofibers to improve the anti-aging properties of the prepared nanofibers and modified the contents of different UV 1/AN-1135. The structure and properties of the PU nanofiber membrane were characterized and analyzed. The results showed that the addition of UV 1/AN-1135 improved the anti-aging properties of PU nanofibers. When the UV 1/AN-1135 content is 1 wt%, the fiber membrane can absorb most of the ultraviolet rays, and the nanofibers have the smallest diameter (135.97 nm). The most uniform is that the transmittance of the fiber film is above 80% and the gas permeability test result is greater than 800 mm/s. After UV aging treatment, the fiber membrane with UV 1/AN-1135 content of 1 wt% still maintains the highest tensile strength (after aging: breaking strength 21.61 MPa, breaking elongation 115.04%) and optimal filtration performance (after aging: the efficiency is 96.925%, the filtration resistance is 30.66 Pa, and the quality factor is 0.1136).","PeriodicalId":54299,"journal":{"name":"Journal of Fiber Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2115/fiberst.2020-0022","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43204042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-15DOI: 10.2115/fiberst.2020-0023
Peng Cui, Yi Zhang, Yuan Xue
: Ring spinning is a yarn formation process that includes drafting, twisting, spinning and winding steps in which fibers are twisted around each other and rapidly rotated around the central axis of the spindle. The collective actions of the twisting, spinning and winding steps produce the coupled transverse and axial motion of the fiber strands. Therefore, yarn formation is a nonhomogeneous process with mutually coupled kinematics and dynamics, which make it difficult to predict the tension of yarn in ring spinning. In this work, we implemented force and displacement sensors in the ring-spinning frame. By solving coupled physical-mathematical equations with the measured parameters, we obtained the real-time dynamics of yarn tension. The results of this study offer insight into the mechanics of yarn formation and failure in ring spinning.
{"title":"Detection and Analysis of Real-Time Dynamics of Yarn Tensions in a Ring Spinning Frame","authors":"Peng Cui, Yi Zhang, Yuan Xue","doi":"10.2115/fiberst.2020-0023","DOIUrl":"https://doi.org/10.2115/fiberst.2020-0023","url":null,"abstract":": Ring spinning is a yarn formation process that includes drafting, twisting, spinning and winding steps in which fibers are twisted around each other and rapidly rotated around the central axis of the spindle. The collective actions of the twisting, spinning and winding steps produce the coupled transverse and axial motion of the fiber strands. Therefore, yarn formation is a nonhomogeneous process with mutually coupled kinematics and dynamics, which make it difficult to predict the tension of yarn in ring spinning. In this work, we implemented force and displacement sensors in the ring-spinning frame. By solving coupled physical-mathematical equations with the measured parameters, we obtained the real-time dynamics of yarn tension. The results of this study offer insight into the mechanics of yarn formation and failure in ring spinning.","PeriodicalId":54299,"journal":{"name":"Journal of Fiber Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49222861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-15DOI: 10.2115/fiberst.2020-0024
A. Yamanaka, M. Terada, M. Ichiki, Yukitane Kimoto, Koji Shiraki, Mikio Nagata, Daisuke Shimamoto, Y. Hotta
: Fiber orientation is important for the development of carbon fiber reinforced thermoplastics (CFRTPs). The purpose of this work is the development of an easy and effective technique to analyze carbon fiber (CF) orientation in CFRTPs in a short time. For this purpose, we investigated the CF orientations in CFRTPs reinforced with polyamide 6 (PA6) as observed by X-ray diffraction (XRD), and discuss the suitability of XRD for the measurement of the CF orientation in CFRTPs. The 200, 002, and 202 reflections of PA6; and the 002 reflection of graphite were observed in the XRD pattern of the CFRTPs. The XRD pattern of uni-directional CFRTP (UD-CFRTP) in the diffraction angle ( 2 θ ) range from 25̊ to 33̊ was almost entirely dominated by contributions from CF. The dependence of the 002 XRD intensity in the 2 θ range from 25̊ to 33̊ on the azimuth ( I(φ) ) of UD-CFRTP and cloth CFRTP (c-CFRTP) showed the CF orientations in those. The direction and distribution of the CF orientations in the discontinuous CF reinforced thermoplastics (D-CFRTP) could be estimated based on the I(φ) obtained by the XRD. Each test piece showed a variable direction and distribution of CF orientation. Fiber orientation order parameters of D-CFRTPs were estimated by I(φ) obtained from the XRD of D-CFRTP and that of UD-CFRTP. The CFs in the D-CFRTP were almost oriented along the molding direction. The tensile modulus was correlated with the orientation order parameters estimated from the XRD patterns of the D-CFRTP. We could obtain these results from studying a UD-CFRTP, a c-CFRTP and a D-CFRTP with performing easy measurements using a general XRD system for 10min. Therefore, XRD may be the one of the most effective methods for the estimation of CF orientations in CFRTPs reinforced with PA6.
{"title":"Evaluation of Fiber Orientation by X-Ray Diffraction on Carbon Fiber Reinforced Polyamide 6","authors":"A. Yamanaka, M. Terada, M. Ichiki, Yukitane Kimoto, Koji Shiraki, Mikio Nagata, Daisuke Shimamoto, Y. Hotta","doi":"10.2115/fiberst.2020-0024","DOIUrl":"https://doi.org/10.2115/fiberst.2020-0024","url":null,"abstract":": Fiber orientation is important for the development of carbon fiber reinforced thermoplastics (CFRTPs). The purpose of this work is the development of an easy and effective technique to analyze carbon fiber (CF) orientation in CFRTPs in a short time. For this purpose, we investigated the CF orientations in CFRTPs reinforced with polyamide 6 (PA6) as observed by X-ray diffraction (XRD), and discuss the suitability of XRD for the measurement of the CF orientation in CFRTPs. The 200, 002, and 202 reflections of PA6; and the 002 reflection of graphite were observed in the XRD pattern of the CFRTPs. The XRD pattern of uni-directional CFRTP (UD-CFRTP) in the diffraction angle ( 2 θ ) range from 25̊ to 33̊ was almost entirely dominated by contributions from CF. The dependence of the 002 XRD intensity in the 2 θ range from 25̊ to 33̊ on the azimuth ( I(φ) ) of UD-CFRTP and cloth CFRTP (c-CFRTP) showed the CF orientations in those. The direction and distribution of the CF orientations in the discontinuous CF reinforced thermoplastics (D-CFRTP) could be estimated based on the I(φ) obtained by the XRD. Each test piece showed a variable direction and distribution of CF orientation. Fiber orientation order parameters of D-CFRTPs were estimated by I(φ) obtained from the XRD of D-CFRTP and that of UD-CFRTP. The CFs in the D-CFRTP were almost oriented along the molding direction. The tensile modulus was correlated with the orientation order parameters estimated from the XRD patterns of the D-CFRTP. We could obtain these results from studying a UD-CFRTP, a c-CFRTP and a D-CFRTP with performing easy measurements using a general XRD system for 10min. Therefore, XRD may be the one of the most effective methods for the estimation of CF orientations in CFRTPs reinforced with PA6.","PeriodicalId":54299,"journal":{"name":"Journal of Fiber Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41360372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-30DOI: 10.2115/fiberst.2020-0016
Hailan Jin, R. Kose, T. Okayama
Reed pulp fiber is one of the main pulp fiber and has been used for a long time in China. The length of the fiber is 1.12 mm corresponding to a hardwood pulp fiber [1-3]. Therefore, in China, the reed pulp fiber is using for packaging paper, book paper and sanitary paper widely, in particular, printing paper. In addition, most softwood and hardwood wood pulps are used as raw materials [4, 5], and research on cellulose nanofiber (CNF) from non-wood pulp is still limited. Furthermore, in the future, an eco-process to produce CNF will need more and more. Therefore, we focus on the CNF from the reed pulp fiber by Aqueous counter collision (ACC) treatment using only water without chemical agent [6]. The cellulose framework in plant cell walls consists of crystalline nanofibers 4‒15 nm wide, with a strength reaching 10 times that of steel despite having a mass one-fifth that of steel [7‒9]. CNF is expected to be widely used as a composite material, an absorbent material, and a biopharmaceutical material due to its high strength, high specific surface area, high biocompatibility, and biodegradability. For these reasons it is being widely studied [10‒12]. Chemical and mechanical treatment of natural pulp fibers yield CNFs defibrillated to a width of 4 to 100 nm [13]. TEMPO catalyzed oxidation by a 2,2,6,6tetramethylpiperidine-1-oxyl catalyst [14, 15] is commonly carried out. Mechanical processing includes grinding [16], mechanical high-pressure homogenization [17], high-speed collision treatment [18], high-intensity ultrasonic treatment [19], and ACC treatment [6]. While various preparation methods for CNF have been developed, none have a clear advantage in terms of conditions, equipment investment, or running costs, nor in terms of minimizing damage to cellulose type I and nano-fibers [20]. The ACC method is considered to be useful because it does not destroy the molecular structure of cellulose [21, 22]. The ACC method is a method for refining CNF by colliding natural fiber dispersions at high speed. This is also known as a wet method, and CNF is prepared as a dispersion of several wt% [23, 24]. Not only the development of new applications of CNF as high-performance materials is expected, but the use of CNF in pulp and paper production is also important. Currently, it is expected to be applied to 【Transaction】
{"title":"Addition of Reed-Derived Cellulose Nanofibers to Change Handsheet Properties","authors":"Hailan Jin, R. Kose, T. Okayama","doi":"10.2115/fiberst.2020-0016","DOIUrl":"https://doi.org/10.2115/fiberst.2020-0016","url":null,"abstract":"Reed pulp fiber is one of the main pulp fiber and has been used for a long time in China. The length of the fiber is 1.12 mm corresponding to a hardwood pulp fiber [1-3]. Therefore, in China, the reed pulp fiber is using for packaging paper, book paper and sanitary paper widely, in particular, printing paper. In addition, most softwood and hardwood wood pulps are used as raw materials [4, 5], and research on cellulose nanofiber (CNF) from non-wood pulp is still limited. Furthermore, in the future, an eco-process to produce CNF will need more and more. Therefore, we focus on the CNF from the reed pulp fiber by Aqueous counter collision (ACC) treatment using only water without chemical agent [6]. The cellulose framework in plant cell walls consists of crystalline nanofibers 4‒15 nm wide, with a strength reaching 10 times that of steel despite having a mass one-fifth that of steel [7‒9]. CNF is expected to be widely used as a composite material, an absorbent material, and a biopharmaceutical material due to its high strength, high specific surface area, high biocompatibility, and biodegradability. For these reasons it is being widely studied [10‒12]. Chemical and mechanical treatment of natural pulp fibers yield CNFs defibrillated to a width of 4 to 100 nm [13]. TEMPO catalyzed oxidation by a 2,2,6,6tetramethylpiperidine-1-oxyl catalyst [14, 15] is commonly carried out. Mechanical processing includes grinding [16], mechanical high-pressure homogenization [17], high-speed collision treatment [18], high-intensity ultrasonic treatment [19], and ACC treatment [6]. While various preparation methods for CNF have been developed, none have a clear advantage in terms of conditions, equipment investment, or running costs, nor in terms of minimizing damage to cellulose type I and nano-fibers [20]. The ACC method is considered to be useful because it does not destroy the molecular structure of cellulose [21, 22]. The ACC method is a method for refining CNF by colliding natural fiber dispersions at high speed. This is also known as a wet method, and CNF is prepared as a dispersion of several wt% [23, 24]. Not only the development of new applications of CNF as high-performance materials is expected, but the use of CNF in pulp and paper production is also important. Currently, it is expected to be applied to 【Transaction】","PeriodicalId":54299,"journal":{"name":"Journal of Fiber Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49078588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-30DOI: 10.2115/fiberst.2020-0018
Hongyi Gan, T. Kabe, T. Iwata
: Paramylon̶a β -1,3-glucan photoproduced by Euglena ̶is a promising raw material for bio-based plastics. Three kinds of paramylon ester derivatives̶paramylon propionate (PaPr), paramylon butyrate (PaBu), and paramylon valerate (PaVa)̶were synthesized to manufacture melt-spun fibers. The melt processing temperatures were determined by combining differential scanning calorimetry (DSC) and a melt flow test. The molecular orientation, crystallinity, and tensile properties of the melt-spun fibers were investigated using a polarized optical microscope (POM), wide-angle X-ray diffraction (WAXD), and tensile testing, respectively. The POM revealed that the PaPr molecular chains were aligned along the spinning direction, despite variation in the take-up rate. However, WAXD confirmed that crystallization only occurred in PaPr fibers spun at a higher take-up rate of over 108 m/min, suggesting that crystallization is induced by high shearing force. This phenomenon seems to be due to the rigid mainchain structure consisting of pyranose rings. With further annealing of the PaPr fibers, the tensile strength increased with an increase in crystallinity. These tendencies were also observed in the PaBu and PaVa melt-spun fibers. The melt-spun fibers of paramylon ester derivatives were manufactured from powders without any additives.
:由绿藻光产生的Paramylon - a β -1,3-葡聚糖是一种很有前途的生物基塑料原料。合成了三种酰胺酯衍生物——丙酸酰胺(PaPr)、丁酸酰胺(pab)和戊酸酰胺(PaVa)——用于制备熔融纺丝纤维。采用差示扫描量热法(DSC)和熔体流动试验相结合的方法确定了熔体加工温度。利用偏光显微镜(POM)、广角x射线衍射(WAXD)和拉伸测试分别研究了熔融纺丝纤维的分子取向、结晶度和拉伸性能。POM显示，尽管吸收率不同，但PaPr分子链沿自旋方向排列。然而，WAXD证实，结晶只发生在吸收率高于108 m/min的PaPr纤维中，这表明结晶是由高剪切力引起的。这种现象似乎是由于由吡喃糖环组成的刚性主链结构所致。进一步退火后，纤维的抗拉强度随着结晶度的增加而增加。在PaBu和PaVa熔纺纤维中也观察到这些趋势。以不添加任何添加剂的粉末为原料制备了酰胺酯衍生物的熔融纺丝纤维。
{"title":"Manufacture, Characterization, and Structure Analysis of Melt-Spun Fibers Derived from Paramylon Esters","authors":"Hongyi Gan, T. Kabe, T. Iwata","doi":"10.2115/fiberst.2020-0018","DOIUrl":"https://doi.org/10.2115/fiberst.2020-0018","url":null,"abstract":": Paramylon̶a β -1,3-glucan photoproduced by Euglena ̶is a promising raw material for bio-based plastics. Three kinds of paramylon ester derivatives̶paramylon propionate (PaPr), paramylon butyrate (PaBu), and paramylon valerate (PaVa)̶were synthesized to manufacture melt-spun fibers. The melt processing temperatures were determined by combining differential scanning calorimetry (DSC) and a melt flow test. The molecular orientation, crystallinity, and tensile properties of the melt-spun fibers were investigated using a polarized optical microscope (POM), wide-angle X-ray diffraction (WAXD), and tensile testing, respectively. The POM revealed that the PaPr molecular chains were aligned along the spinning direction, despite variation in the take-up rate. However, WAXD confirmed that crystallization only occurred in PaPr fibers spun at a higher take-up rate of over 108 m/min, suggesting that crystallization is induced by high shearing force. This phenomenon seems to be due to the rigid mainchain structure consisting of pyranose rings. With further annealing of the PaPr fibers, the tensile strength increased with an increase in crystallinity. These tendencies were also observed in the PaBu and PaVa melt-spun fibers. The melt-spun fibers of paramylon ester derivatives were manufactured from powders without any additives.","PeriodicalId":54299,"journal":{"name":"Journal of Fiber Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67638806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-04-20DOI: 10.2115/fiberst.2020-0012
T. Honda, W. Sakai, K. Miyazaki, K. Hisada
: A cotton fabric has high water absorption and good touch, so it has been used as clothes since ancient times. Electron beam (EB) induced graft polymerization is one of the chemical modification methods for polymer materials such as fibers and films. In this study, it was shown that uniform modification can be achieved through EB-induced graft polymerization even with unrefined cotton sliver. The Cotton sliver can be used not only for fabrics but also for knits and nonwoven fabrics and so on. ESR spectroscopy and the degree of grafting showed that the amount of radical generated in the original sliver was smaller than that for the sliver after scouring and bleaching. A more remarkable difference was observed in the amount of active radical that could initiate the graft polymerization. Nevertheless, it was possible to modify the cotton sliver that had not been scoured and bleached through the EB-induced graft polymerization if the graft polymerization could be completed within 90 min. Microprobe Raman spectroscopy revealed that the generated graft chains were uniformly distributed inside the sliver. A comparison of the reactivity of monomers in different dispersion states in water showed that the monomers forming small dispersion units in water tended to have the higher degree of grafting. The diffusion process in which the monomer reaches the active site in the sliver before their disappearance must be key process for the graft polymerization to proceed.
{"title":"Effect of Scouring and Bleaching on Chemical Modification of Cotton Sliver by EB-Induced Graft Polymerization","authors":"T. Honda, W. Sakai, K. Miyazaki, K. Hisada","doi":"10.2115/fiberst.2020-0012","DOIUrl":"https://doi.org/10.2115/fiberst.2020-0012","url":null,"abstract":": A cotton fabric has high water absorption and good touch, so it has been used as clothes since ancient times. Electron beam (EB) induced graft polymerization is one of the chemical modification methods for polymer materials such as fibers and films. In this study, it was shown that uniform modification can be achieved through EB-induced graft polymerization even with unrefined cotton sliver. The Cotton sliver can be used not only for fabrics but also for knits and nonwoven fabrics and so on. ESR spectroscopy and the degree of grafting showed that the amount of radical generated in the original sliver was smaller than that for the sliver after scouring and bleaching. A more remarkable difference was observed in the amount of active radical that could initiate the graft polymerization. Nevertheless, it was possible to modify the cotton sliver that had not been scoured and bleached through the EB-induced graft polymerization if the graft polymerization could be completed within 90 min. Microprobe Raman spectroscopy revealed that the generated graft chains were uniformly distributed inside the sliver. A comparison of the reactivity of monomers in different dispersion states in water showed that the monomers forming small dispersion units in water tended to have the higher degree of grafting. The diffusion process in which the monomer reaches the active site in the sliver before their disappearance must be key process for the graft polymerization to proceed.","PeriodicalId":54299,"journal":{"name":"Journal of Fiber Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49274290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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