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Binary Relations between Magnitudes of Different Dimensions Used in Material Science Optimization Problems Pseudo-State Equation of Soft Magnetic Composites
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作者 Krzysztof Z.Sokalski Bartosz Jankowski Barbara Slusarek 《Materials Sciences and Applications》 2014年第14期1040-1047,共8页
New algorithm for optimizing technological parameters of soft magnetic composites has been derived on the base of topological structure of the power loss characteristics. In optimization magnitudes obeying scaling, it... New algorithm for optimizing technological parameters of soft magnetic composites has been derived on the base of topological structure of the power loss characteristics. In optimization magnitudes obeying scaling, it happens that one has to consider binary relations between the magnitudes having different dimensions. From mathematical point of view, in general case such a procedure is not permissible. However, in a case of the system obeying the scaling law it is so. It has been shown that in such systems, the binary relations of magnitudes of different dimensions is correct and has mathematical meaning which is important for practical use of scaling in optimization processes. The derived structure of the set of all power loss characteristics in soft magnetic composite enables us to derive a formal pseudo-state equation of Soft Magnetic Composites. This equation constitutes a relation of the hardening temperature, the compaction pressure and a parameter characterizing the power loss characteristic. Finally, the pseudo-state equation improves the algorithm for designing the best values of technological parameters. 展开更多
关键词 Soft Magnetic composites SCALING binary Relations Pseudo-State Equation
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QSPR modeling of azeotropic temperatures and compositions for binary azeotropes containing lower alcohols using a genetic function approximation 被引量:6
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作者 Yixin Ma Kang Ma +4 位作者 Huixin Wang Xueli Geng Jun Gao Zhaoyou Zhu Yinglong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第4期835-844,共10页
Binary azeotropes, which contain two chemicals with a relative volatility of 1, are very common in the chemical industry. Understanding azeotropes is essential for effectively separating binary azeotropes containing l... Binary azeotropes, which contain two chemicals with a relative volatility of 1, are very common in the chemical industry. Understanding azeotropes is essential for effectively separating binary azeotropes containing lower alcohols. Experimental techniques and ab initio approaches can produce accurate results;however, these two processes are time consuming and labor intensive. Although thermodynamic equations such as UNIFAC are widely used, experimental values are required, and it is difficult to choose the best groups to represent a complex system. Because of their high efficiency and fast calculation speed, quantitative structure–property relationship(QSPR) tools were used in this work to predict the azeotropic temperatures and compositions of binary azeotropes containing lower alcohols. The QSPR models for 64 binary azeotropes based on centroid approximation and weighted-contribution-factor approximation were established using the genetic function approximation(GFA) procedure in Materials Studio software, and a leave-one-out cross-validation procedure was conducted.External tests of an additional 16 azeotropes were also investigated, and high determination coefficient values were obtained. The best QSPR models were explained in terms of the molecular structure of the azeotropes,and good predictive ability was obtained within acceptable prediction error levels. 展开更多
关键词 QSPR AZEOTROPIC temperature AZEOTROPIC composition Genetic function approximation binary AZEOTROPES
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EXPERIMENTAL STUDY ON PEK -C MODIFIED EPOXIES AND THE CARBON FIBER COMPOSITES FOR AEROSPACE APPLICATION 被引量:7
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作者 李暘暘 益小苏 唐邦明 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2000年第4期242-249,共8页
The morphological structure of various epoxies toughened with a special amorphous thermoplastic PEK-C and their carbon fiber composites were studied by using SEM. For both cases, phase separation and inversion took pl... The morphological structure of various epoxies toughened with a special amorphous thermoplastic PEK-C and their carbon fiber composites were studied by using SEM. For both cases, phase separation and inversion took place to form fine epoxy-rich globules dispersing in the PEK-C matrix, in which the epoxy-rich phase had the absolutely higher volume fraction. The phase structure and the interfacial properties were also studied by means of FTIR, DSC, and DMTA as well. An accompanying mechanical determination revealed that an improved toughness was achieved both in the blend casts and in the carbon fiber composites. A composite structural model was hence suggested. 展开更多
关键词 PEK-C thermoset/thermoplastic binary system phase behavior interface TOUGHNESS carbon fiber composites
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Carbon nanomaterials and their composites for supercapacitors 被引量:15
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作者 Mingzhu Zhong Miao Zhang Xifei Li 《Carbon Energy》 SCIE CAS 2022年第5期950-985,共36页
As a type of energy storage device between traditional capacitors and batteries,the supercapacitor has the advantages of energy saving and environmental protection,high power density,fast charging and discharging spee... As a type of energy storage device between traditional capacitors and batteries,the supercapacitor has the advantages of energy saving and environmental protection,high power density,fast charging and discharging speed,long cycle life,and so forth.One of the key factors affecting the performance of supercapacitor is the electrode material.Carbon materials,such as carbon nanotube,graphene,activated carbon,and carbon nanocage,are most widely concerned in the application of supercapacitors.The synergistic effect of composites can often obtain excellent results,which is one of the common strategies to increase the electrochemical performance of supercapacitors.To further improve the performance of binary composites,it is a relatively simple method to increase the components as the“bridge”between the two materials to form the ternary composites.The review mainly introduces the current research progress of supercapacitors with pure carbon nanomaterials and multistage carbon nanostructures(composites)as electrodes.The characteristics and application directions of different pure carbon nanomaterials are introduced in detail.Different ways of multilevel structure(material)composite have their own effects on the development of high-performance supercapacitors.We also highlight the recent advances related to these fields and provide our insight into high-energy supercapacitors. 展开更多
关键词 binary composite carbon nanomaterials SUPERCAPACITORS ternary composite
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Three-Dimensional Reconstructed Finite Element Model for C/C Composites by Micro-CT 被引量:3
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作者 张海军 周储伟 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第6期639-645,共7页
The precise microscopic feature of carbon-carbon(C/C) composites is essential {or an accurate predic tion of their mechanical behavior. After fabrication, actual microscopic feature differs from simple ideal spatial... The precise microscopic feature of carbon-carbon(C/C) composites is essential {or an accurate predic tion of their mechanical behavior. After fabrication, actual microscopic feature differs from simple ideal spatial model. Micro computed lomography(CT) scan can well describe internal microstruetures of composites. Therefore, a reconstructed model is developed based on mireo-CT, by a series of prodcedures including extrac tlng components, generating new binary images and establishing a finite element (FE) model. Compared with the model designed by reconstructed commercial software MIMICS. the presented reconstructed FE model is superior in terms of high mesh quality and eontrollable mesh cluantity. The precision of the model is verified by experiment. 展开更多
关键词 C/C composites mirco-CF binary image reconstructed procedure finite element model
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COMPOSITION DETERMINATION OF BINARY POLYMER MIXTURES BY SIZE EXCLUSION CHROMATOGRAPHY WITH LIGHT SCATTERING DETECTION 被引量:2
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作者 程镕时 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第3期291-297,共7页
Base on the principle of absolute quantification of size exclusion chromatography (SEC), a light scattering (LS) detector coupled with a concentration detector (refractive index detector) is utilized to determin... Base on the principle of absolute quantification of size exclusion chromatography (SEC), a light scattering (LS) detector coupled with a concentration detector (refractive index detector) is utilized to determine the compositions of complicated binary mixtures. A theoretical analysis predicts that the response factors for both LS and RI detectors are linear functions with the composition of any specified polymer mixtures in the binary polymer mixtures. Two pairs of complicated binary mixtures were used to test the theory mentioned in the present paper, and the experimental results show an excellent accordance with the theory. 展开更多
关键词 Size exclusion chromatography Light scattering composition of binary mixture Absolute quantification Response factor.
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Emission-Reductive and Multi-Objective Coordinative Optimization of Binary Feed for Atmospheric and Vacuum Distillation Unit 被引量:3
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作者 Huang Xiaoqiao Zhao Tianlong +3 位作者 Li Na Ma Zhanhua Song Lijuan Li Jun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2017年第4期101-112,共12页
A genetic algorithm based multi-objective coordinative optimization strategy is developed to optimize the operation of a binary feed atmospheric and vacuum distillation system, in which the objective functions cover t... A genetic algorithm based multi-objective coordinative optimization strategy is developed to optimize the operation of a binary feed atmospheric and vacuum distillation system, in which the objective functions cover the economic benefit, the furnace energy consumption and the CO_2 emissions, and meanwhile the simultaneous effect of binary feed composition is also investigated. A cross-call integration of software is developed to implement the optimization algorithm,and once the maximum economic benefit, the minimum furnace energy consumption and the minimum CO_2 emissions are obtained, the Pareto-optimal solution set is worked out, with the practical problems of the refinery being solved. The optimization result shows that under the same furnace energy consumption and the CO_2 emissions as the existing working condition, the economic benefit still allows for a considerable potential of increment by adjusting the heavy oil proportion of the binary feed crude oil. 展开更多
关键词 MULTI-OBJECTIVE OPTIMIZATION atmospheric and vacuum DISTILLATION system genetic algorithm CO2 emissions binary FEED composition
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基于复合图双卷积神经网络的路面裂缝识别方法
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作者 王浩仰 潘宗俊 +2 位作者 曹建坤 张洁 郭宝栋 《公路交通科技》 CAS CSCD 北大核心 2024年第9期1-9,共9页
为了建立一种基于深度学习卷积神经网络的路面检测模型,提高特殊路面裂缝,如白裂缝、浅裂缝、潮湿裂缝、修补开裂等的识别准确率,在单卷积神经网络结构(单网络)上,提出了基于复合图双卷积神经网络的路面裂缝识别方法。首先,该方法在输... 为了建立一种基于深度学习卷积神经网络的路面检测模型,提高特殊路面裂缝,如白裂缝、浅裂缝、潮湿裂缝、修补开裂等的识别准确率,在单卷积神经网络结构(单网络)上,提出了基于复合图双卷积神经网络的路面裂缝识别方法。首先,该方法在输入灰度图基础上,考虑裂缝病害图像特征,增加对应二值图组成复合图通道;其次,在单网络结构基础上增加一个针对特殊裂缝识别的单网络,非特殊裂缝网络训练使用全部数据,特殊裂缝网络训练使用特殊裂缝数据,两个网络参数分别独立更新,从而形成复合图双网络结构;然后两个网络分别对同一测试数据进行判定,得出各自的概率矩阵,最后再根据概率单侧抑制的原理将两个单网络输出结果进行叠加,得出最终识别结果。组织了70万张检测车采集图片对复合图双网络方法进行训练和测试。结果表明,复合图双网络识别重叠度、精确度、召回率显著优于灰度图单网络,证明了提出的两处优化,即将单通道灰度图改造为双通道复合输入图和增加一个特殊裂缝识别网络,提升了非特殊裂缝与特殊裂缝区域识别能力。此外,复合图双网络的重叠度、精确度、召回率指标比其他深度学习路面裂缝识别算法方法高。 展开更多
关键词 智能交通 裂缝识别方法 复合图双卷积神经网络 路面裂缝 二值图
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基于离焦二值显示和条纹投影的复合表面三维测量方法
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作者 邵金凤 倪育博 +7 位作者 孟召宗 高楠 高宇森 杨泽青 张国锋 尹伟 赵洪伟 张宗华 《光电工程》 CAS CSCD 北大核心 2024年第4期88-99,共12页
由于复合表面物体中漫反射部分和镜面部分反射性质不同,受到相机景深的限制,镜面成像的正弦条纹发生离焦,从而引起相位误差。为了实现复合表面物体的高效、高精度测量,本文提出了一种离焦二值结合正弦条纹的复合表面三维形貌测量方法。... 由于复合表面物体中漫反射部分和镜面部分反射性质不同,受到相机景深的限制,镜面成像的正弦条纹发生离焦,从而引起相位误差。为了实现复合表面物体的高效、高精度测量,本文提出了一种离焦二值结合正弦条纹的复合表面三维形貌测量方法。首先,本文基于刃边法与二次模糊法对系统离焦程度进行分区标定,解决了由于相机倾斜放置导致参考面离焦程度不同的问题。然后,建立二值条纹相位误差模型,确定最佳条纹宽度和离焦量范围。最后,对轻微离焦区域的二值条纹进行离焦补偿,确保相机采集的条纹均在最佳离焦范围内。在此基础上进行三维形貌测量。实验结果表明,所提方法使镜面部分误差从原来的0.033 mm降至0.019 mm,提高了复合表面测量精度。 展开更多
关键词 复合表面测量 二值离焦技术 离焦估计 参数选择 离焦补偿
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基于二元堆积理论高致密CuW复合材料制备及耐电弧侵蚀性能研究
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作者 张懿铭 宋克兴 +6 位作者 国秀花 皇涛 冯江 王旭 李韶林 钟建英 李凯 《表面技术》 EI CAS CSCD 北大核心 2024年第14期181-189,共9页
目的提高CuW复合材料的致密度及耐电弧侵蚀性能。方法基于二元堆积理论设计并制备了双粒径W颗粒混杂CuW75复合材料,通过微观组织表征、硬度测试、导电率测试及密度测试,重点对比研究了单粒径CuW75复合材料和双粒径混杂CuW75复合材料致... 目的提高CuW复合材料的致密度及耐电弧侵蚀性能。方法基于二元堆积理论设计并制备了双粒径W颗粒混杂CuW75复合材料,通过微观组织表征、硬度测试、导电率测试及密度测试,重点对比研究了单粒径CuW75复合材料和双粒径混杂CuW75复合材料致密性和微观组织的内在关联,并通过电接触实验研究了双粒径混杂CuW75复合材料耐电弧的侵蚀性能。结果双粒径混杂CuW75复合材料微观组织均匀,W相及Cu相网络连通程度高,致密度高达99.79%,较CuW75复合材料国家标准致密度提升了2.9%,硬度较CuW75复合材料国家标准提升了6.7%。电接触实验结果表明,双粒径混杂CuW75复合材料熔焊力波动幅度小,平均熔焊力(35.06cN)较1μm单粒径CuW75复合材料的降低了11%;平均燃弧能量(147.29mJ)及平均燃弧时间(2.53ms)较1μm单粒径CuW75复合材料的分别下降了38%和36%。双粒径混杂CuW75复合材料受电弧侵蚀面积小,侵蚀坑较浅,耐电弧侵蚀性能优异。结论双粒径混杂W颗粒制备CuW复合材料可以明显提升材料的致密度及微观结构连通性。双粒径混杂CuW复合材料可以更好地分散电弧,具有优异的抗熔焊性能及耐电弧侵蚀性能。 展开更多
关键词 二元堆积理论 双粒径混杂 CuW复合材料 熔焊力 微观组织
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砾岩油藏二元复合驱注入体系优化研究
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作者 曹锦鸿 高明 +2 位作者 刘皖露 刘朝霞 桑国强 《科学技术与工程》 北大核心 2024年第12期4952-4958,共7页
新疆克拉玛依砾岩油藏经过几十年的水驱开发,面临剩余油高度分散、采油速度低等问题,选取聚合物部分水解聚丙烯酰胺(HPAM)和低张力表面活性剂PS-30及强乳化表面活性剂OP-10组合形成不同的二元复合体系,利用长砂管模型研究不同渗透率、... 新疆克拉玛依砾岩油藏经过几十年的水驱开发,面临剩余油高度分散、采油速度低等问题,选取聚合物部分水解聚丙烯酰胺(HPAM)和低张力表面活性剂PS-30及强乳化表面活性剂OP-10组合形成不同的二元复合体系,利用长砂管模型研究不同渗透率、不同驱替方式及不同注入量下复合驱体系在砾岩油藏的应用界限及提高采收率极限。实验结果表明:二元复合驱能够有效驱替残余油、扩大波及体积,显著提高砾岩油藏采收率。聚合物浓度为1000 mg/L,相对分子质量为7×10^(6)的聚合物在渗透率3×10^(-2)μm^(2)时复合驱采收率为66.31%,较水驱提高21.85个百分点。强乳化复合体系提高采收率效果好于低张力复合体系。复合体系注入量越高,提高采收率越大,但提高采收率幅度并非线性变化,复合体系注入量达到3.5 PV以后,复合体系提高采收率值逐渐趋于稳定,在注入10 PV后,复合驱体系最高提高采收率幅度达到40.38个百分点。 展开更多
关键词 聚/表二元复合驱 砾岩油藏 表面活性剂 提高采收率
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硼基金属复合物的点火和燃烧特性研究进展
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作者 李锐霄 庞维强 蔚红建 《火炸药学报》 EI CAS CSCD 北大核心 2024年第3期197-208,I0003,共13页
综述了近几年国内外硼基金属复合物点火和燃烧特性的最新研究进展,重点归纳了二元硼基金属复合物、三元硼基金属复合物和纳米硼基金属复合物的点火和燃烧研究现状,并对比了其优缺点,其中对二元硼基金属复合物的研究较为丰富,对三元硼基... 综述了近几年国内外硼基金属复合物点火和燃烧特性的最新研究进展,重点归纳了二元硼基金属复合物、三元硼基金属复合物和纳米硼基金属复合物的点火和燃烧研究现状,并对比了其优缺点,其中对二元硼基金属复合物的研究较为丰富,对三元硼基金属复合物的研究大多集中于制备方向,关于点火和燃烧特性研究较少,对纳米基金属复合物的点火燃烧机理尚不清楚。指出了硼基金属复合物未来的研究方向:(1)对于制备工艺较简单的二元硼基金属复合物,下一步应具体研究其工艺对产物性能的影响;(2)利用分子动力学和有限元分析的方法对其燃烧机理进一步分析;(3)关于纳米硼基金属复合物可考虑建立一种稳定悬浮液进一步探究其点火和燃烧机制。附参考文献71篇。 展开更多
关键词 材料科学 硼基金属复合物 点火燃烧特性 二元硼基金属复合物 三元硼基金属复合物 纳米硼基金属复合物
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二元复合驱提高石油采收率技术研究
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作者 江伟 张钰 +2 位作者 张小荣 郭启峰 付国超 《石化技术》 CAS 2024年第1期56-58,共3页
二元复合驱是控制注水井区含水上升速度,进一步提高采收率的方法,并能有效提高驱油效果,它与三元复合驱相比,具有施工简单、成本低、地层伤害小等优势。二元复合驱技术在油田中的应用逐渐普及,如何通过二元复合驱实现稳油控水,提高油田... 二元复合驱是控制注水井区含水上升速度,进一步提高采收率的方法,并能有效提高驱油效果,它与三元复合驱相比,具有施工简单、成本低、地层伤害小等优势。二元复合驱技术在油田中的应用逐渐普及,如何通过二元复合驱实现稳油控水,提高油田采出程度成为亟待探究的内容。基于此,通过对XZ油田提高采收率现状及常用技术进行调研与对比,提出目前XZ油田在提高采收率方面面临的挑战,通过室内实验研究了二元复合驱,并在现场取得了一定的效果。 展开更多
关键词 二元复合驱 采收率 稳油控水 技术研究
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二元复合氧化物载体在加氢脱硫催化剂中的应用进展
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作者 周文武 何欣欣 +4 位作者 唐小原 周安宁 陈治平 黄志豪 白业兴 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第9期1361-1374,共14页
加氢脱硫技术对实现劣质油品清洁化、低碳化与多元化高效利用至关重要,其关键是高性能催化剂的开发,核心之一是适宜催化剂载体材料的创新。本工作分别总结了向Al_(2)O_(3)及TiO_(2)中引入第二组元后作为加氢脱硫催化剂载体的研究进展。... 加氢脱硫技术对实现劣质油品清洁化、低碳化与多元化高效利用至关重要,其关键是高性能催化剂的开发,核心之一是适宜催化剂载体材料的创新。本工作分别总结了向Al_(2)O_(3)及TiO_(2)中引入第二组元后作为加氢脱硫催化剂载体的研究进展。第二组元氧化物的引入克服了Al_(2)O_(3)载体酸类型单一及商用催化剂金属与载体间相互作用过强等缺点,同时保持了较大的比表面积;第二组元氧化物能够有效提升TiO_(2)载体材料的热稳定性及比表面积的同时调节了载体材料表面酸性等。究其原因在于第二组元的引入可显著改变Al_(2)O_(3)或TiO_(2)表面羟基环境,进而促进了活性金属前驱体在载体表面的锚定和分散,有利于更多NiMo(W)S活性相的形成,提升了催化剂的加氢脱硫性能。 展开更多
关键词 二元复合氧化物 铝基氧化物 钛基氧化物 载体表面环境 加氢脱硫催化剂
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Y_(3)Si_(2)C_(2)掺量对Si_(3)N_(4)陶瓷微观结构与力/热学性能的影响
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作者 龙国钦 聂光临 +5 位作者 陈炫志 黎业华 彭小晋 黄瑶 邓欣 伍尚华 《陶瓷学报》 CAS 北大核心 2024年第3期539-548,共10页
Si_(3)N_(4)陶瓷具有优异的力学、化学、热学性能,在电子元器件散热与封装领域具有良好的应用前景。为制备高强度、高导热的Si_(3)N_(4)陶瓷,采用Y_(3)Si_(2)C_(2)-MgO二元复合烧结助剂,系统研究了Y_(3)Si_(2)C_(2)掺量与保温时间对Si_(... Si_(3)N_(4)陶瓷具有优异的力学、化学、热学性能,在电子元器件散热与封装领域具有良好的应用前景。为制备高强度、高导热的Si_(3)N_(4)陶瓷,采用Y_(3)Si_(2)C_(2)-MgO二元复合烧结助剂,系统研究了Y_(3)Si_(2)C_(2)掺量与保温时间对Si_(3)N_(4)陶瓷致密度、力学性能及热导率的影响规律,并基于微观结构和物相组成分析阐释了Si_(3)N_(4)陶瓷力/热学性能的优化机制。研究结果表明:随着Y_(3)Si_(2)C_(2)掺量的增加,Si_(3)N_(4)陶瓷试样(保温时间分别为4 h和12 h)的热导率和弯曲强度均呈现先增大后降低的变化规律;保温4 h所制Si_(3)N_(4)陶瓷的弯曲强度主要受致密度的影响,保温12 h所制Si_(3)N_(4)陶瓷的弯曲强度主要受微观结构的均匀度及晶粒尺寸的影响;保温时间的延长有利于气体排出和晶粒生长,从而促进Si_(3)N_(4)陶瓷的致密化及热导率的提升。利用气压烧结(1900℃保温12 h),掺加1.5 mol%的Y_(3)Si_(2)C_(2)可制得致密度为99.0%、热导率为(106.80±2.64)W·m^(−1)·K^(−1)、弯曲强度为(590.21±25.69)MPa的Si_(3)N_(4)陶瓷,其具有优良的力/热学综合性能,有利于提升Si_(3)N_(4)陶瓷封装电子元器件的服役安全性与可靠性。 展开更多
关键词 Si_(3)N_(4)陶瓷 二元复合烧结助剂 Y_(3)Si_(2)C_(2) 热导率 力学性能 微观结构
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EPR/PP/M-CNF纳米复合材料的制备及性能研究
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作者 韩贤新 王宇威 +5 位作者 樊丽权 姜永旺 岳莹 许珂琳 李玉鑫 刘喜军 《齐齐哈尔大学学报(自然科学版)》 2024年第4期70-74,共5页
纤维素纳米纤维(CNF)经碱液预处理得到碱预处理纤维素纳米纤维(APCNF),再通过二元乙丙橡胶接枝乙烯醇(EPR-g-VA)接枝共聚物溶液处理后,得到改性纤维素纳米纤维(M-CNF)。然后将M-CNF添加到EPR/PP共混体系中,制备EPR/PP/M-CNF纳米复合材... 纤维素纳米纤维(CNF)经碱液预处理得到碱预处理纤维素纳米纤维(APCNF),再通过二元乙丙橡胶接枝乙烯醇(EPR-g-VA)接枝共聚物溶液处理后,得到改性纤维素纳米纤维(M-CNF)。然后将M-CNF添加到EPR/PP共混体系中,制备EPR/PP/M-CNF纳米复合材料。通过扫描电子显微镜、偏光显微镜、热重分析仪、动态热机械分析仪、电子万能试验机等对EPR/PP/M-CNF纳米复合材料的微观形貌、球晶尺寸、热稳定性以及力学性能进行分析测试。结果表明,EPR、EPR-g-VA包覆APCNF形成“核-壳”结构;相对于EPR/PP共混物,EPR/PP/M-CNF纳米复合材料的热学性能和力学性能均有明显提高,EPR/PP/M-CNF纳米复合材料的冲击强度和初始热分解温度分别为13.80 kJ/m^(2)和368.73℃,并且复合材料中PP相的球晶尺寸变小,晶界面模糊。 展开更多
关键词 聚丙烯 二元乙丙橡胶 复合材料 纤维素纳米纤维
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基于GPU的北斗B1宽带复合信号实时发生器设计
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作者 王子涵 巴晓辉 +3 位作者 姜维 蔡伯根 王剑 文韬 《系统工程与电子技术》 EI CSCD 北大核心 2024年第3期795-804,共10页
为了实现北斗B1C+B1I信号的联合生成,提出一种基于软件无线电和图形处理器(graphics processing unit,GPU)加速的北斗B1宽带复合信号的实时生成方法,该方法针对单边带复数二进制偏移载波(single-sideband complex binary offset carrier... 为了实现北斗B1C+B1I信号的联合生成,提出一种基于软件无线电和图形处理器(graphics processing unit,GPU)加速的北斗B1宽带复合信号的实时生成方法,该方法针对单边带复数二进制偏移载波(single-sideband complex binary offset carrier,SCBOC)调制方式的信号体制进行设计,系统根据用户配置的接收机运动轨迹和星历文件,生成中频信号并通过射频端发射。为了进一步提升GPU并行运算速度,从优化设备内存结构、设计并行线程架构和统一计算设备架构流(compute unified device architecture stream,CUDA)加速3个方面,设计了基于异步运算的加速采样点数据计算的CUDA优化实现方案。测试结果证明,优化后的算法可以基于SCBOC调制实时生成北斗B1I+B1C信号,基于GTX3060的GPU平台,信号90 M采样率下能实现8颗卫星复合信号的实时生成。 展开更多
关键词 B1宽带复合信号 软件无线电 单边带复数二进制偏移载波调制 统一计算设备架构流 实时生成
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耐温抗盐强乳化聚-表二元复合驱油体系研究及应用 被引量:1
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作者 许文赟 潘彬 +3 位作者 李鑫 王颐同 邵彤 朱璐 《西安石油大学学报(自然科学版)》 北大核心 2024年第1期48-55,共8页
针对高温高盐油藏采用常规聚合物和表面活性剂驱油效果较差的问题,将耐温抗盐型聚合物SPAM-1和阴-非离子复合型表面活性剂YANC-E进行复配,研制了一种适合高温高盐油藏的耐温抗盐强乳化聚-表二元复合驱油体系,并通过室内实验评价了驱油... 针对高温高盐油藏采用常规聚合物和表面活性剂驱油效果较差的问题,将耐温抗盐型聚合物SPAM-1和阴-非离子复合型表面活性剂YANC-E进行复配,研制了一种适合高温高盐油藏的耐温抗盐强乳化聚-表二元复合驱油体系,并通过室内实验评价了驱油体系的综合性能。结果表明:该二元复合驱油体系的耐温性能较强,在115℃下老化后,体系的黏度保留率仍能达到90%以上,界面张力仍能达到10^(-3)mN/m数量级;体系具有良好的抗盐性能,当矿化度大于100000 mg/L时,体系仍能保持较高的黏度和较低的界面张力;体系具有良好的长时间老化稳定性能,在储层温度和矿化度条件下老化60 d后的黏度保留率在85%以上,界面张力始终维持在10^(-3)mN/m范围内;驱油体系与原油形成的乳状液稳定性较强,放置120 min后乳状液的分水率小于20%,具有较强的乳化性能;驱油体系在地层条件下吸附6次后仍能保持较高的黏度和较低的界面张力,具有良好的抗吸附性能。另外,岩心水驱结束后注入0.5 PV二元复合驱油体系,能使采收率继续提高25%以上,驱油效果较好。A区块内5口采油井在实施耐温抗盐强乳化聚-表二元复合驱油措施后,日产油量显著提高,含水率明显降低,取得了良好的现场应用效果。 展开更多
关键词 高温高盐 聚-表二元复合驱 乳化性能 吸附性能 驱油性能
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Composite electrolytes based on poly(ethylene oxide) and binary ionic liquids for dye-sensitized solar cells 被引量:1
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作者 YU YingHao JIANG Peng +2 位作者 WANG FuRong WANG LeFu LI XueHui 《Science China Chemistry》 SCIE EI CAS 2012年第8期1608-1613,共6页
The sunlight is the largest single available source of clean and renewable energy to ensure human society's sustainable devel- opment. Owing to their low production cost and high energy conversion efficiency, dye-sen... The sunlight is the largest single available source of clean and renewable energy to ensure human society's sustainable devel- opment. Owing to their low production cost and high energy conversion efficiency, dye-sensitized solar cells (DSSCs) have been regarded as good alternatives to conventional photovoltaic devices. Herein, a series of composite electrolytes based on poly(ethylene oxide) (PEO) and the binary ionic liquids 1-propyl-3-methy-imidazolium iodide ([PMIm]I) and l-ethyl-3- methylimidazolium thiocyanate ([EMIm][SCN]) were prepared and then applied to fabricate six DSSCs. The composite elec- trolytes were characterized by fourier transform infrared spectroscopy (FTIS), X-ray diffraction (XRD), and electrochemical impedance spectra (EIS). It was shown that the addition of binary ionic liquids would reduce the degree of crystallinity of PEO thus improving the ionic conductivities of the electrolytes by about 2 orders of magnitude. Investigation on the photovoltaic performances of these DSSCs showed that the fill factor (FF) could reach up to 0.67 and energy conversion efficiency (η) could reach up to 4.04% under AM 1.5 full sunlight (100 mW/cm^2). 展开更多
关键词 solar energy dye-sensitized solar cell PEO binary ionic liquid composite electrolyte
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CaCO_3/SiO_2复合粒子涂层的表面结构及其疏水性能研究 被引量:13
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作者 杨金鑫 文秀芳 +3 位作者 皮丕辉 郑大锋 程江 杨卓如 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2009年第1期91-96,共6页
以机械高速搅拌法制备了具有草莓结构的CaCO3/S iO2复合粒子,并对其进行了表面修饰改性.利用聚硅氧烷的自组装功能,将制备的复合粒子与硅氧烷一起制备了具有“荷叶效应”的超疏水涂层,静态水接触角达169°,滚动角约为2°.通过... 以机械高速搅拌法制备了具有草莓结构的CaCO3/S iO2复合粒子,并对其进行了表面修饰改性.利用聚硅氧烷的自组装功能,将制备的复合粒子与硅氧烷一起制备了具有“荷叶效应”的超疏水涂层,静态水接触角达169°,滚动角约为2°.通过扫描电镜观察涂层的表面微观形貌,发现该涂层具有微米-纳米相结合的双层粗糙结构.微米凸起的粒径在2~3μm左右,纳米凸起的粒径约为200nm左右,与荷叶具有类似的结构排布方式.通过原子力显微镜和接触角的测试,探讨了表面微观结构、涂层粗糙度和涂层疏水性能之间的关系.结果表明:复合粒子构成的非均相界面的水接触角符合Cassie模型.复合粒子赋予涂层的双微观粗糙结构与自组装成膜硅氧烷的低表面能的协同效应,使涂层具有了优良的超疏水性能. 展开更多
关键词 复合粒子 双微观结构 超疏水
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