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生物基长链聚酰胺1210弹性体的制备、性能与非等温结晶动力学
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作者 陈向阳 龚舜 +2 位作者 周阳 赵彪 潘凯 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第10期21-28,共8页
生物基长链热塑性聚酰胺弹性体(TPAE)近年来引起了学术界和工业界的广泛关注。文中以聚醚胺与生物基长链聚酰胺1210分别作为软硬段,成功制备得到了聚醚胺型生物基长链聚酰胺1210弹性体(TPAE 1210),其具有高的相对分子质量和窄的分布度,... 生物基长链热塑性聚酰胺弹性体(TPAE)近年来引起了学术界和工业界的广泛关注。文中以聚醚胺与生物基长链聚酰胺1210分别作为软硬段,成功制备得到了聚醚胺型生物基长链聚酰胺1210弹性体(TPAE 1210),其具有高的相对分子质量和窄的分布度,力学性能媲美同类商品。TPAE 1210弹性体主要形成α晶型,且聚醚胺对晶区内的链结构规整性有较大影响,导致加热过程中出现二次结晶行为。利用差示扫描量热法研究了TPAE 1210的非等温结晶动力学过程,结果表明,其初级结晶过程主要通过异相成核进行一维生长,二次结晶过程主要进行二维生长。采用Kissinger法计算得TPAE 1210的结晶活化能为-144.4 kJ/mol。 展开更多
关键词 生物基 长链聚酰胺 热塑性弹性体 非等温结晶
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聚多巴胺修饰聚对苯撑苯并双噁唑纤维增强其抗老化性与功能性 被引量:6
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作者 陈凤贵 张明忠 +4 位作者 陈林飞 陈相杨 腾晓旭 高镱萌 周剑锋 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第5期153-160,共8页
高性能纤维聚对苯撑苯并双噁唑(PBO)容易受紫外光照射而导致其性能显著下降。为了提高PBO材料的抗老化性能,文中通过简易方法在纤维表面直接修饰富含酚羟基的纳米厚度的聚多巴胺薄层,并比较研究了初始纤维与多巴胺修饰纤维在紫外光照射... 高性能纤维聚对苯撑苯并双噁唑(PBO)容易受紫外光照射而导致其性能显著下降。为了提高PBO材料的抗老化性能,文中通过简易方法在纤维表面直接修饰富含酚羟基的纳米厚度的聚多巴胺薄层,并比较研究了初始纤维与多巴胺修饰纤维在紫外光照射前后的力学性能、热稳定性能、结晶取向等性能的变化。结果表明,未经修饰的PBO纤维的力学等性能在紫外光照射后显著下降,如拉伸强度下降了67%;而表面经过修饰的PBO纤维在经过紫外光照射后,其性能变化显著减小,如拉伸强度仅下降了33%。并且,聚多巴胺修饰的PBO纤维对污染物罗丹明B染料等具有一定的吸附性能,吸附24 h的吸附容量达0.25 mg/g。因此,在材料表面修饰聚多巴胺层可有效改善PBO纤维的抗紫外光老化性能,提高了材料的功能性。 展开更多
关键词 抗老化性能 表面修饰 聚对苯撑苯并双噁唑 聚多巴胺 力学性能 罗丹明B
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长碳链聚醚酰胺永久型抗静电剂的制备与性能 被引量:8
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作者 许冬峰 陈向阳 +2 位作者 桂源 冯新星 潘凯 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第8期36-41,共6页
以自制的长碳链聚醚酰胺弹性体(TPAE)为基体,通过加入不同种类的碱金属钠盐与锂盐,采用熔融挤出加工的方法制备了聚醚酰胺永久型抗静电剂。重点研究了不同含量的高氯酸锂(LiClO_4)对TPAE性能的影响,采用高阻计、扫描电镜、红外光谱对抗... 以自制的长碳链聚醚酰胺弹性体(TPAE)为基体,通过加入不同种类的碱金属钠盐与锂盐,采用熔融挤出加工的方法制备了聚醚酰胺永久型抗静电剂。重点研究了不同含量的高氯酸锂(LiClO_4)对TPAE性能的影响,采用高阻计、扫描电镜、红外光谱对抗静电剂的表面电阻率、淬断面结构、化学结构进行了表征,并对其拉伸性能和耐漂洗性等进行了研究。结果表明,LiClO_4的质量分数为6%时,其在TPAE中分布均匀,抗静电效果较好,表面电阻率可以达到2×10~7Ω/sq,断裂伸长率在600%以上,而且抗静电性不会因为漂洗而失去,抗静电效果持久,是一种性能优异的永久型抗静电剂。 展开更多
关键词 长碳链聚醚酰胺 永久型抗静电剂 表面电阻率 高氯酸锂 抗静电效果
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Foreign Fiber Image Segmentation Based on Maximum Entropy and Genetic Algorithm 被引量:3
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作者 Liping chen xiangyang chen +2 位作者 Sile Wang Wenzhu Yang Sukui Lu 《Journal of Computer and Communications》 2015年第11期1-7,共7页
In machine-vision-based systems for detecting foreign fibers, due to the background of the cotton layer has the absolute advantage in the whole image, while the foreign fiber only account for a very small part, and w... In machine-vision-based systems for detecting foreign fibers, due to the background of the cotton layer has the absolute advantage in the whole image, while the foreign fiber only account for a very small part, and what’s more, the brightness and contrast of the image are all poor. Using the traditional image segmentation method, the segmentation results are very poor. By adopting the maximum entropy and genetic algorithm, the maximum entropy function was used as the fitness function of genetic algorithm. Through continuous optimization, the optimal segmentation threshold is determined. Experimental results prove that the image segmentation of this paper not only fast and accurate, but also has strong adaptability. 展开更多
关键词 FOREIGN Fibers Image SEGMENTATION MAXIMUM ENTROPY GENETIC Algorithm
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Research on Destriping Based on Rough Set 被引量:1
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作者 xiangyang chen Liping chen +2 位作者 Sile Wang Wenzhu Yang Sukui Lu 《Journal of Computer and Communications》 2015年第11期8-12,共5页
In order to remove the stripe noises in cotton foreign fiber images by line scanning camera collected, in multi threshold segmentation of rough set, every region’s color is instead of the statistics color of the regi... In order to remove the stripe noises in cotton foreign fiber images by line scanning camera collected, in multi threshold segmentation of rough set, every region’s color is instead of the statistics color of the region. This method can retain the detail information of original image as far as possible, and do well in the stripe noise removal. The roughness of rough set was calculated respectively using directional diagram, Canny operator and Sobel operator. Comparing the three methods, the results indicate that the Canny operator keeps the more details of image, and directional diagram and Sobel operator have the better effects on denoising. 展开更多
关键词 STRIPE NOISES Multi THRESHOLD Segmentation ROUGH Set Denosing
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Chromatic and achromatic differences of melanin-and carotenoid-based plumage coloration in five minivet species(Pericrocotus spp.)under conspecific and predator visual systems
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作者 Yan Cai xiangyang chen +1 位作者 Neng Wu Canchao Yang 《Avian Research》 SCIE CSCD 2023年第1期93-98,共6页
Adaptive mate choice has been accepted as the leading theory to explain the colorful plumage of birds.This theory hypothesizes that conspicuous colors act as signals to advertise the qualities of the owners.However,a ... Adaptive mate choice has been accepted as the leading theory to explain the colorful plumage of birds.This theory hypothesizes that conspicuous colors act as signals to advertise the qualities of the owners.However,a dilemma arises in that conspicuous colors may not only attract mates,but also alert predators.The"private channels of communication"hypothesis proposes that some intraspecific signals may not be visible to heterospecific animals because of different visual systems.To better understand the evolution of plumage colors and sexual selection in birds,here we studied the chromatic difference and achromatic differences of melanin-and carotenoid-based plumage coloration in five minivet species(Pericrocotus spp.)under conspecific and predator visual systems.We found that either the chromatic or achromatic difference among male or female minivets’plumage was consistently higher under conspecific vision than under predator vision for all five studied species of minivets.This result indicated that individual differences in plumage colors of minivets were visible to the conspecific receivers and hidden from potential predators as a result of evolution under predation risk and conspecific communication.However,males were under a higher risk of predation because they were more conspicuous than females to the vision of a nocturnal predator. 展开更多
关键词 Achromatic difference Adaptive mate choice Chromatic difference Omamental plumage Visual modelling
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Use of 3D-printed animal models as a standard method to test avian behavioral responses toward nest intruders in the studies of avian brood parasitism
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作者 xiangyang chen Yan Cai +1 位作者 Jiaojiao Wang Canchao Yang 《Avian Research》 SCIE CSCD 2022年第4期487-490,共4页
Living and/or non-living animal models are often used as stimuli to observe the behavioral responses of the target animals.In the past,parasites,predators,and harmless controls have been used to test host anti-parasit... Living and/or non-living animal models are often used as stimuli to observe the behavioral responses of the target animals.In the past,parasites,predators,and harmless controls have been used to test host anti-parasitism defense behavior,and their taxidermy specimens have been widely used as a set of standard methods for the study of avian brood parasitism.In recent years,with the rapid development of 3D-printing technology,3D-printed bird models are expected to be applied as a standard method in the study of avian brood parasitism.To evaluate the use of 3D-printed models,this study tests the reaction of Oriental Reed Warbler(Acrocephalus orientalis)towards predators,parasites,or controls,and compares the reaction among different nest intruders and between taxidermy specimens and 3D-printed animal models.It was found that the Oriental Reed Warbler responded most aggressively to the parasite,followed by predator,and finally the control;the results were consistent between the reaction to taxidermy specimens and 3D-printed animal models,indicating that 3D-printed models could serve as a substitute for taxidermy specimens.We propose a series of advantages of using 3D-printed models and suggest them to be a standard method for widespread use in future studies of avian brood parasitism. 展开更多
关键词 Animal behavior Cuckoo parasitism Taxidermy specimens 3D-printed technology
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Research progress in geophysical exploration of the Antarctic ice sheet
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作者 Jinkai An Song Huang +2 位作者 xiangyang chen Tao Xu Zhiming Bai 《Earthquake Research Advances》 CSCD 2023年第3期72-84,共13页
The Antarctic ice sheet is an important target of Antarctic research.Thickness and structure,including intraice and subice,are closely related to the mass balance of the ice sheet,and play an important role in the stu... The Antarctic ice sheet is an important target of Antarctic research.Thickness and structure,including intraice and subice,are closely related to the mass balance of the ice sheet,and play an important role in the study of global sea level and climate change.Subglacial topography is an important basis for studying ice sheet dynamics and ice sheet evolution.This paper briefly reviews the geophysical detection methods and research status of the Antarctic ice sheet:(1)Conventional methods such as ice radar are the main methods for studying the ice sheet today,and passive source seismic methods such as the receiver function method,H/V method and P-wave coda autocorrelation method have good development prospects;(2)the high-resolution(1 km)ice thickness and subglacial topographic database BEDMAP2 established based on various data has greatly improved the ability to detect internal isochronous layers,anisotropic layers,and temperature changes within ice and has advanced research on ice sheet evolution;and(3)ice radar,numerical simulation and core drilling are the main methods to study subglacial lakes and sediments.More than 400 subglacial lakes have been confirmed,and more than 12000 simulation results have been obtained.Research on the Antarctic ice sheet faces enormous challenges and is of great urgency.Aiming at hot issues,such as Antarctic geological evolution,glacial retreat,ice sheet melting and their relationships with global climate change,it is the frontier and trend of future Antarctic ice sheet research to carry out multidisciplinary and multicountry comprehensive geophysical exploration based on the traditional ice radar method combined with passive seismic methods,especially new technologies such as short-period dense array technology,unmanned aerial vehicles and artificial intelligence.This is expected to further promote Antarctic research. 展开更多
关键词 Antarctic ice sheet Intra-and subglacial structures Ice sheet mass balance INTERDISCIPLINARY Integrated geophysical exploration
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Xijiao Dihuang Decoction combined with Yinqiao Powder reverses influenza virus-induced F-actin reorganization in PMVECs by inhibiting ERM phosphorylation
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作者 Zinan Xuan Ying Wu +7 位作者 chenyue Zhang Shujing Zhang xiangyang chen Shuyu Li Yu Hao Qian Wang Xudan Wang Shu Zhang 《Journal of Traditional Chinese Medical Sciences》 2016年第1期50-58,共9页
Objective:It has been documented that ezrin/radixin/moesin(ERM)phosphorylation by the p38 mitogen-activated protein kinase(MAPK),Rho/ROCK,and protein kinase C(PKC)pathways leads to filamentous actin(F-actin)reorganiza... Objective:It has been documented that ezrin/radixin/moesin(ERM)phosphorylation by the p38 mitogen-activated protein kinase(MAPK),Rho/ROCK,and protein kinase C(PKC)pathways leads to filamentous actin(F-actin)reorganization and microvascular endothelial cell hyperpermeability.In this study,we investigated the effects of Xijiao Dihuang Decoction combined with Yinqiao Powder(XDY)on influenza virus(IV)-induced F-actin restructuring and ERM phosphorylation regulated by the Rho/Rho kinase 1(ROCK),p38 MAPK,and PKC signaling pathways in pulmonary microvascular endothelial cells(PMVECs).Methods:Serum containing XDY(XDY-CS;13.8 g/kg)was acquired using standard protocols for serum pharmacology.Primary PMVECs were obtained from male Wistar rats and cultured.After adsorption of IV A(multiplicity of infection,0.01)for 1 h,medium with 20%XDY-CS was added to the PMVECs.The distributions of F-actin and phosphorylated ERM were determined by confocal microscopy,and F-actin expression was measured by flow cytometry.The expression levels of ROCK1,phosphorylated myosin phosphatase target-subunit(p-MYPT),phosphorylated MAPK kinase,phosphorylated p38(p-p38),phosphorylated PKC(p-PKC),and phosphorylated ERM(p-ERM)were determined by western blotting.Results:F-actin reorganization in IV-infected PMVECs was reversed by XDY-CS treatment,which was accompanied by reduced p-ERM production.The p-ERM protein accumulated at plasma membrane of PMVECs infected with IV,which was also inhibited by XDY-CS treatment. 展开更多
关键词 Xijiao Dihuang Decoction combined with Yinqiao Powder Influenza virus Pulmonary microvascular endothelial cells Filamentous actin Ezrin/radixin/moesin
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The SNAPc complex mediates starvation-induced trans-splicing in Caenorhabditis elegans
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作者 Xinhao Hou chengming Zhu +5 位作者 Mingjing Xu xiangyang chen cheng Sun Björn Nashan Shouhong Guang Xuezhu Feng 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2022年第10期952-964,共13页
Dietary restriction usually suppresses biosynthesis but activates catabolic pathways in animals.However,the short-term starvation enhances biosynthetic activities and promotes ribosomal biogenesis in adult Caenorhabdi... Dietary restriction usually suppresses biosynthesis but activates catabolic pathways in animals.However,the short-term starvation enhances biosynthetic activities and promotes ribosomal biogenesis in adult Caenorhabditis elegans.The mechanism underlying the processes remains largely unknown.Here,we find that the short-term starvation enhances the SL1 trans-splicing of translation-related genes in adult C.elegans by transcriptome analysis.The small nuclear RNA-activating protein complex(SNAPc)promotes SL RNA production and mediates starvation-induced trans-splicing.TOFU-5,a core factor in the upstream sequence transcription complex(USTC)essential for piRNA production,is also involved in the starvationinduced trans-splicing processes.Knocking down components of the SNAPc complex and tofu-5 extends worm survival under starvation conditions.Taken together,our study highlights the importance of SL transsplicing in the nutrition response and reveals a mechanism of the survival regulation by food deprivation via SNAPc and TOFU-5. 展开更多
关键词 TRANS-SPLICING SNAPc tofu-5 STARVATION C.elegans
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Parent-offspring and inter-offspring responses to conspecific versus heterospecific distress calls in 2 sympatric birds
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作者 Yuxin JIANG Jingru HAN +2 位作者 Ziqi ZHANG xiangyang chen Canchao YANG 《Current Zoology》 SCIE CAS CSCD 2022年第6期700-707,共8页
Distress calls,as a type of alarm call,play important roles in expressing bodily condition and conveying information concerning predation threats.In this study,we examined the communication via distress calls in paren... Distress calls,as a type of alarm call,play important roles in expressing bodily condition and conveying information concerning predation threats.In this study,we examined the communication via distress calls in parent–offspring and inter-offspring interactions.First,we used playback of chick distress calls of 2 sympatric breeders,the vinous-throated parrotbill Sinosuthora webbiana and the oriental reed warbler Acrocephalus orientalis,to the adults/chicks of these 2 species,respectively,and measured the responses of conspecifics or heterospecifics.The playback-to-chicks experiment showed that both species of chicks reduced the number of begging calls and begging duration time as a response to conspecific/heterospecific distress calls compared with natural begging and background noise controls.However,reed warbler chicks also reduced beak opening frequency in the response to conspecific distress calls compared with other playback stimuli.Second,the results of the playback-to-adults experiment showed that reed warbler adults could eavesdrop on distress calls of conspecific neighbors and sympatric heterospecifics.Furthermore,the nest-leaving behavior of reed warblers did not differ significantly when they heard the distress calls of conspecifics or parrotbills.Finally,reed warbler adults responded to heterospecific distress calls more quickly than to conspecific distress calls,and parrotbill adults presented the same response.Our results supported the warnkin hypothesis and show that chick distress calls play an important role in conveying risk and the condition of chicks to enhance individual fitness.In addition,we also found that eavesdropping on distress calls is a congenital behavior that begins in the chick stage. 展开更多
关键词 acoustic communication call recognition chick-chick system eavesdropping parent-offspring system
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Microstructure,Mechanical,and Tribological Properties of CN_x Thin Films Prepared by Reactive Magnetron Sputtering
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作者 xiangyang chen Jin Zhang +2 位作者 Shengli Ma Haixia Hu Zhebo Zhou 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2014年第1期31-36,共6页
The microstructure, mechanical, and tribological properties of the carbon nitride (CNx) thin films with different nitrogen contents deposited on high-speed steel substrates by reactive magnetron sputtering were stud... The microstructure, mechanical, and tribological properties of the carbon nitride (CNx) thin films with different nitrogen contents deposited on high-speed steel substrates by reactive magnetron sputtering were studied. CNx films with nitrogen contents from 10.7 to 28.2 at.% had an amorphous structure composing of the carbon bonds of sp2C-C, sp2C-N, and sp3C-N. The TiN inter-layer cause the adhesion of CNx films enhancement. The more nitrogen concentration led to larger film hardness and friction coefficient against GCrl5 steel balls, but the wear rates decreased. 展开更多
关键词 Reactive magnetron sputtering (RMS) CNx film MICROSTRUCTURE TRIBOLOGY
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Down image recognition based on deep convolutional neural network
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作者 Wenzhu Yang Qing Liu +4 位作者 Sile Wang Zhenchao Cui xiangyang chen Liping chen Ningyu Zhang 《Information Processing in Agriculture》 EI 2018年第2期246-252,共7页
Since of the scale and the various shapes of down in the image,it is difficult for traditional image recognition method to correctly recognize the type of down image and get the required recognition accuracy,even for ... Since of the scale and the various shapes of down in the image,it is difficult for traditional image recognition method to correctly recognize the type of down image and get the required recognition accuracy,even for the Traditional Convolutional Neural Network(TCNN).To deal with the above problems,a Deep Convolutional Neural Network(DCNN)for down image classification is constructed,and a new weight initialization method is proposed.Firstly,the salient regions of a down image were cut from the image using the visual saliency model.Then,these salient regions of the image were used to train a sparse autoencoder and get a collection of convolutional filters,which accord with the statistical characteristics of dataset.At last,a DCNN with Inception module and its variants was constructed.To improve the recognition accuracy,the depth of the network is deepened.The experiment results indicate that the constructed DCNN increases the recognition accuracy by 2.7% compared to TCNN,when recognizing the down in the images.The convergence rate of the proposed DCNN with the new weight initialization method is improved by 25.5% compared to TCNN. 展开更多
关键词 Deep convolutional neural network Weight initialization Sparse autoencoder Visual saliency model Image recognition
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