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Influence of Waveguide Properties on Wave Prototypes Likely to Accompany the Dynamics of Four-Wave Mixing in Optical Fibers
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作者 Jean Roger Bogning Marcelle Nina Zambo Abou’ou +4 位作者 Christian Regis Ngouo Tchinda Mathurin Fomekong Oriel Loh Ndichia Stallone Mezezem Songna François Béceau Pelap 《Journal of Applied Mathematics and Physics》 2024年第7期2601-2633,共33页
In this article, we study the impacts of nonlinearity and dispersion on signals likely to propagate in the context of the dynamics of four-wave mixing. Thus, we use an indirect resolution technique based on the use of... In this article, we study the impacts of nonlinearity and dispersion on signals likely to propagate in the context of the dynamics of four-wave mixing. Thus, we use an indirect resolution technique based on the use of the iB-function to first decouple the nonlinear partial differential equations that govern the propagation dynamics in this case, and subsequently solve them to propose some prototype solutions. These analytical solutions have been obtained;we check the impact of nonlinearity and dispersion. The interest of this work lies not only in the resolution of the partial differential equations that govern the dynamics of wave propagation in this case since these equations not at all easy to integrate analytically and their analytical solutions are very rare, in other words, we propose analytically the solutions of the nonlinear coupled partial differential equations which govern the dynamics of four-wave mixing in optical fibers. Beyond the physical interest of this work, there is also an appreciable mathematical interest. 展开更多
关键词 Optical Fiber Four Waves mixing Implicit Bogning Function Coupled Nonlinear Partial Differential Equations Nonlinear Coefficient Dispersive Coefficient Waveguide Properties
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甲酸铵含量对现场混装乳胶基质流变及热分解性能的影响
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作者 何志伟 岳嘉伟 +2 位作者 黄振祎 胡前浩 周圣涛 《高压物理学报》 CAS 北大核心 2025年第1期53-63,共11页
为提高现场混装乳化炸药的耐高温性能,制备了4种不同甲酸铵含量的现场混装乳化炸药基质样品。采用旋转流变仪和同步热分析仪研究了4种样品的流动性、黏弹性、黏温及其热分解性能。结果表明:加入甲酸铵可以提高现场混装乳胶基质的黏度,... 为提高现场混装乳化炸药的耐高温性能,制备了4种不同甲酸铵含量的现场混装乳化炸药基质样品。采用旋转流变仪和同步热分析仪研究了4种样品的流动性、黏弹性、黏温及其热分解性能。结果表明:加入甲酸铵可以提高现场混装乳胶基质的黏度,且随着甲酸铵质量分数的增加,样品的黏度出现先增大后减小的趋势;与未添加甲酸铵的样品相比,加入甲酸铵的样品的弹性模量增大,稳定性增强;当甲酸铵的质量分数不大于9%时,在50℃左右的温度下,乳胶基质的黏度均能够满足泵送要求;甲酸铵的加入对乳胶基质的热分解过程没有明显影响;随着甲酸铵质量分数的增加,其外推起始分解温度、活化能、热爆炸临界温度和自加速分解温度均有所增加,现场混装乳胶基质的热稳定性和热安全性得到提升。 展开更多
关键词 现场混装乳化炸药基质 甲酸铵 流变性能 热分解性能
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Mixed grain structure and mechanical property anisotropy of AZ40 magnesium alloy bar with diameter of 160 mm 被引量:1
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作者 石国梁 张奎 +4 位作者 李兴刚 李永军 马鸣龙 袁家伟 卢春芳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期3944-3952,共9页
The mixed grain structure and mechanical property anisotropy of AZ40 magnesium alloy bar with a diameter of 160 mm manufactured by "multi-direction forging(MDF) + extrusion + online cooling" technique were inves... The mixed grain structure and mechanical property anisotropy of AZ40 magnesium alloy bar with a diameter of 160 mm manufactured by "multi-direction forging(MDF) + extrusion + online cooling" technique were investigated by optical microscopy(OM), scanning electron microscopy(SEM), X-ray diffraction macro-texture measurement and room temperature(RT) tensile test. The results show that mixed grain structure is caused by the micro-segregation of Al in semi-continuous casting ingot. Homogenization of(380 °C, 8 h) +(410 °C, 12 h) cannot totally eliminate such micro-segregation. During MDF and extrusion, the dendrite interiors with 3%-4% Al(mass fraction) transform to fine grain zones, yet the dendrite edges with about 6% Al transform to coarse grain zones. XRD macro-textures of the outer, R/2 and center show typical fiber texture characteristics and the intensity of [0001]//Ra D orientation in the outer(11.245) is about twice as big as those in the R/2(6.026) and center(6.979). The as-extruded AZ40 magnesium alloy bar has high elongation(A) and moderate ultimate tensile strength(Rm) in both extrusion direction(ED) and radius direction(Ra D), i.e., A of 19%-25% and Rm of 256-264 MPa; however, yield strength(Rp0.2) shows anisotropy and heterogeneity, i.e., 103 MPa in Ra D, 137 MPa in ED-C(the center) and 161 MPa in ED-O(the outer), which are mainly caused by the texture.(155 °C, 7 h) +(170 °C, 24 h) aging has no influence on strength and elongation of AZ40 magnesium bar. 展开更多
关键词 AZ40 magnesium alloy mixed grain structure mechanical properties ANISOTROPY MICRO-SEGREGATION texture
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基于产权视角的国有控股混合所有制企业长效机制建设
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作者 公维莲 綦好东 朱炜 《财经问题研究》 北大核心 2025年第1期59-71,共13页
党的十八大以来,混合所有制改革作为国有企业最为深刻的产权制度改革方式,在推动完善现代企业制度建设方面取得了良好的绩效。当前,为提升国有控股混合所有制企业的治理效能,更好地实现国有资本功能,需要坚持马克思主义的产权观,同时,... 党的十八大以来,混合所有制改革作为国有企业最为深刻的产权制度改革方式,在推动完善现代企业制度建设方面取得了良好的绩效。当前,为提升国有控股混合所有制企业的治理效能,更好地实现国有资本功能,需要坚持马克思主义的产权观,同时,借鉴西方产权理论的有益成分,探索国有控股混合所有制企业产权配置的长效机制,加快建设与现代企业发展规律相契合的中国特色现代企业制度。本文立足中国特色社会主义基本经济制度的内在规定,紧密联系混合所有制企业产权关系的现状,从主要股东权力制衡机制、控制权与收益权协调机制、劳动要素与资本要素适度融合的激励约束机制三个方面,阐释了国有控股混合所有制企业长效机制建设的理论逻辑与路径,以通过完善公司治理促进中国特色现代企业制度更加成熟定型。 展开更多
关键词 混合所有制企业 产权制度 公司治理 长效机制
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加勒比松针阔混交改造初期对林下植被多样性及土壤理化性质的影响
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作者 张挺 杨德任 +4 位作者 毛纯 朱原立 庞伟灿 杨梅 邓善宝 《北华大学学报(自然科学版)》 CAS 2025年第1期84-92,共9页
从林下植被多样性、土壤理化性质探讨合理的加勒比松人工纯林改良模式,为提高加勒比松纯林生态稳定性及混交林树种选择提供科学依据。以加勒比松纯林(PP)、加勒比松×灰木莲(MF1)、加勒比松×红锥(MF2)、加勒比松×灰木莲&#... 从林下植被多样性、土壤理化性质探讨合理的加勒比松人工纯林改良模式,为提高加勒比松纯林生态稳定性及混交林树种选择提供科学依据。以加勒比松纯林(PP)、加勒比松×灰木莲(MF1)、加勒比松×红锥(MF2)、加勒比松×灰木莲×红锥(MF3)混交林为研究对象,分析4种林分林下植被多样性和土壤理化性质差异。结果显示:1)3种混交林草本层多样性指数均显著高于PP,其中MF1最大,MF3次之;3种混交林灌木层物种丰富度指数均显著提高,Simpson指数、Shannon-Wiener指数仅MF3显著高于PP,Pielou指数差异不显著。2)不同林分间土壤容重差异不显著,3种混交林土壤含水率和土壤孔隙度均高于PP,均为MF3最优。3)除硝态氮外,MF2和MF3的0~20 cm、20~40 cm土层土壤有机碳、全氮、铵态氮、全钾、速效钾和速效磷含量均显著高于PP。4)相关性分析表明,灌木层多样性指数与土壤理化性质的相关性强于草本层,而草本层与土壤速效磷含量的相关性较强;冗余分析表明,土壤有机碳、速效磷是影响林下植被多样性的主要因子。与PP相比,MF1、MF2、MF3均能够显著提高灌木层物种丰富度和草本层植被多样性指数。同时,混交林还改善了土壤水分和孔隙状况,提高了土壤有机碳和氮、磷、钾的全量和有效养分含量,且套种多树种混交改良效果明显优于套种单一树种的混交林。 展开更多
关键词 加勒比松 针阔混交林 林下植被多样性 土壤理化性质
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基于柔性苯二乙酸CM6@Zn-MOF纳米材料的构筑和光电性能研究
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作者 李鹏云 张军 +3 位作者 孙朋涛 张钢强 马雅菲 张美丽 《化学试剂》 CAS 2025年第1期26-32,共7页
金属有机框架(Metal-organic frameworks,简称MOFs)作为有效能量转移的供体,在人工光采集材料领域中已引起许多专家的关注。特别是二维MOFs纳米片,因每个活性位点暴露在外易靠近受体,可以有效地将内部能量转移给外部受体,具有更为非凡... 金属有机框架(Metal-organic frameworks,简称MOFs)作为有效能量转移的供体,在人工光采集材料领域中已引起许多专家的关注。特别是二维MOFs纳米片,因每个活性位点暴露在外易靠近受体,可以有效地将内部能量转移给外部受体,具有更为非凡的光电性能。通过选用柔性的1,2-苯二乙酸(H_(2)opda)和刚性的3,5-二(三氮唑)吡啶(btyp)作为有机配体,合成了一种新型的二维配位聚合物[Zn_(3)(btyp)_(2)(opda)_(3)(H_(2)O)_(3)]·(btyp)(H_(2)O)_(3)(Zn-MOF),晶体属于三斜晶系、P-1空间群。在该晶体结构中,反式opda配体的2个羧基均以双齿螯合模式与Zn(Ⅱ)离子配位,形成一维无限链;btyp配体桥链支撑相邻一维链,构成二维网面;通过opda羧基O与结晶H_(2)O之间多个O—H…O的相互作用形成三维超分子网络结构。Zn-MOF且具有完整的循环伏安曲线(还原、氧化电位分别为-0.22、0.05 V),良好的扫描速率。使用超声粉碎法将Zn-MOF层状结构剥离形成二维纳米片,再与香豆素6(CM6)掺杂形成CM6@Zn-MOF纳米材料,荧光从蓝光向绿光移动,将光收集范围从紫外光扩展到可见光,加之良好的电化学循环伏安性能(还原、氧化电位分别为-0.21、0.08 V),有望成为光电应用新材料。 展开更多
关键词 水热合成 苯二乙酸 香豆素6 晶体结构 掺杂材料 光电性能
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动物性、植物性蛋白与鱼糜混合凝胶品质研究进展
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作者 张馨月 耿文豪 +4 位作者 田苗苗 梁欣 李欣蓉 范馨茹 赵前程 《食品工业科技》 北大核心 2025年第2期17-24,共8页
凝胶特性是衡量鱼糜制品品质的重要指标。鱼糜制品因其营养价值高、味道鲜美、易储运等特点,深受消费者喜爱。随着我国食品制造业的快速发展以及消费群体的多元化,传统鱼糜制品已无法满足消费者对于均衡膳食以及感官特性的需求。因此,... 凝胶特性是衡量鱼糜制品品质的重要指标。鱼糜制品因其营养价值高、味道鲜美、易储运等特点,深受消费者喜爱。随着我国食品制造业的快速发展以及消费群体的多元化,传统鱼糜制品已无法满足消费者对于均衡膳食以及感官特性的需求。因此,新型鱼糜的开发逐渐受到关注,如何利用其他动物性、植物性原料实现具有良好凝胶特性的混合鱼糜制品已成为鱼糜加工行业的研究热点。本文对动物、植物性蛋白与鱼糜凝胶形成机制的研究进展进行汇总,对动物和植物蛋白分别通过促进蛋白间的交联和抑制鱼糜蛋白酶的活性有效地改良鱼糜凝胶性能、保水能力及微观结构等指标进行了阐述,并提出了现阶段混合鱼糜制品品质改良过程中存在感官品质差、改性机制不明确等问题,旨在为新型鱼糜开发及其凝胶特性改良方面的研究提供理论支撑,为进一步开发新型鱼糜提供指导方向。 展开更多
关键词 鱼糜 混合凝胶 凝胶特性 动物蛋白 植物蛋白
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Effect of powder mixing process on the microstructure and thermal conductivity of Al/diamond composites fabricated by spark plasma sintering 被引量:17
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作者 CHU Ke, JIA Chengchang, LIANG Xuebing, and CHEN Hui School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China 《Rare Metals》 SCIE EI CAS CSCD 2010年第1期86-91,共6页
Two powder mixing processes, mechanical mixing (MM) and mechanical alloying (MA), were used to prepare mixed Al/diamond powders, which were subsequently consolidated using spark plasma sintering (SPS) to produce... Two powder mixing processes, mechanical mixing (MM) and mechanical alloying (MA), were used to prepare mixed Al/diamond powders, which were subsequently consolidated using spark plasma sintering (SPS) to produce bulk Al/diamond composites. The effects of the powder mixing process on the morphologies of the mixed powders, the microstructure and the thermal conductivity of the composites were investigated. The results show that the powder mixing process can significantly affect the microstructure and the thermal conductivity of the composites. Agglomerations of the particles occurred in mixed powders using MM for 30 min, which led to high pore content and weak interfacial bonding in the composites and resulted in low relative density and low thermal conductivity for the composites. Mixed powders of homogeneous distribution of diamond particles could be obtained using MA for 10 min and MM for 2 h. The composite prepared through MA indicated a high relative density but low thermal conductivity due to its defects, such as damaged particles, Fe impurity, and local interfacial debonding, which were mainly introduced in the MA process. In contrast, the composite made by MM for 2 h demonstrated high relative density and an excellent thermal conductivity of 325 W.m^-1.K^-1, owing to its having few defects and strong inter-facial bonding. 展开更多
关键词 metal matrix composites thermal properties SINTERING powder mixing
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High-temperature performance prediction of iron ore fines and the ore-blending programming problem in sintering 被引量:8
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作者 Bing-ji Yan Jian-liang Zhang +2 位作者 Hong-wei Guo Ling-kun Chen Wei Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2014年第8期741-747,共7页
The high-temperature performance of iron ore fmes is an important factor in optimizing ore blending in sintering. However, the application of linear regression analysis and the linear combination method in most other ... The high-temperature performance of iron ore fmes is an important factor in optimizing ore blending in sintering. However, the application of linear regression analysis and the linear combination method in most other studies always leads to a large deviation from the desired results. In this study, the fuzzy membership functions of the assimilation ability temperature and the liquid fluidity were proposed based on the fuzzy mathematics theory to construct a model for predicting the high-temperature performance of mixed iron ore. Comparisons of the prediction model and experimental results were presented. The results illustrate that the prediction model is more accurate and effective than previously developed models. In addition, fuzzy constraints for the high-temperature performance of iron ore in this research make the results of ore blending more comparable. A solution for the quantitative calculation as well as the programming of fuzzy constraints is also introduced. 展开更多
关键词 iron ores blending SINTERING high temperature properties prediction PROGRAMMING
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Fabrication of homogeneously dispersed graphene/Al composites by solution mixing and powder metallurgy 被引量:13
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作者 Xiang Zeng Jie Teng +3 位作者 Jin-gang Yu Ao-shuang Tan Ding-fa Fu Hui Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第1期102-109,共8页
Graphene-reinforced aluminum (AI) matrix composites were successfully prepared via solution mixing and powder metallurgy in this study. The mechanical properties of the composites were studied using microhardness an... Graphene-reinforced aluminum (AI) matrix composites were successfully prepared via solution mixing and powder metallurgy in this study. The mechanical properties of the composites were studied using microhardness and tensile tests. Compared to the pure Al alloy, the graphene/Al composites showed increased strength and hardness. A tensile strength of 255 MPa was achieved for the graphene/Al com- posite with only 0.3wt% graphene, which has a 25% increase over the tensile strength of the pure Al matrix. Raman spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy were used to investigate the morphol- ogies, chemical compositions, and microstructures of the graphene and the graphene/A1 composites. On the basis of fractographic evidence, a relevant fracture mechanism is proposed. 展开更多
关键词 GRAPHENE metal matrix composites solution mixing powder metallurgy mechanical properties
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Physical dispersion state and fluorescent property of Eu-complex in the Eu-complex/silicon rubber composites 被引量:5
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作者 温世鹏 胡水 +2 位作者 张小萍 张立群 刘力 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第5期626-632,共7页
The fluorescent complex Eu(TTA)2(Phen)(MA) (HTTA=2-Thenoyltrifluoroacetone, Phen=1,10-phenanthroline, MA=Maleic an- hydrider) was synthesized and characterized with elemental analysis, infrared spectrum (IR)... The fluorescent complex Eu(TTA)2(Phen)(MA) (HTTA=2-Thenoyltrifluoroacetone, Phen=1,10-phenanthroline, MA=Maleic an- hydrider) was synthesized and characterized with elemental analysis, infrared spectrum (IR), scanning electron microscope (SEM), X-ray Diffraction(XRD), differential scanning calorimetry(DSC), and fluorescent measurement. To explore the effect of different physical dispersion state of Eu-complex on the fluorescent property of the Eu-complex/silicon rubber composites, various quantifies of Eu(TTA)2(phen) (MA) were mixed with silicon rubber (SIR) and peroxide to form uncured composites. These composites were vulcanized to obtain cured Eu-complex/SiR composites at 250 ℃, which was higher than the melting-point of Eu-complex. The SEM, XRD, DSC, and the fluorescent measurement of these composites showed that both the complex molecules dispersed in the silicon rubber during the melting process and the parent Eu-complex particles had positive effects on fluorescent property, whereas the re-crystallized Eu-complex particles and the aggregating complexes formed during the melting-process had negative effects on fluorescent property. For the uncured composites, their fluorescent intensities almost did not change with the increasing amount of Eu-complex. Furthermore, for the composites with small content of Eu-complex, their fluorescent intensities decreased significantly after curing, and this difference in fluorescent intensity became smaller as the content of Eu-complex increases. 展开更多
关键词 polymer-matrix composites melting blending physical dispersion state fluorescent property rare earths
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THE EFFECT OF BLENDING SEQUENCE ON PHASE MORPHOLOGY OF NYLON 6/ABS/SMA BLENDS 被引量:3
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作者 Qin, Shu-Hao Yu, Jie +2 位作者 Zheng, Qiang He, Min Zhu, Hong 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第1期73-80,共8页
The preparation process-dependent phase morphology of blends composed of nylon 6 and acrylonitrile-butadiene- styrene(ABS)over a composition range of 30-70 wt% using a styrene-maleic anhydride(SMA)copolymer as the com... The preparation process-dependent phase morphology of blends composed of nylon 6 and acrylonitrile-butadiene- styrene(ABS)over a composition range of 30-70 wt% using a styrene-maleic anhydride(SMA)copolymer as the compatibilizing agent with a constant content(5phr)was investigated.The results of the scanning electron microscope (SEM)observation revealed that compared with the binary blends of nylon 6 and ABS,the existence of SMA caused a composition shift of phase inversion to a higher weight fraction of ny... 展开更多
关键词 Nylon 6 ABS MORPHOLOGY blending sequence Dynamic mechanical properties
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Influence of Blending Temperature on Fluorescence Properties of Silicone Rubber Matrix Eu(TTA)_2(phen)(MA) Composites 被引量:3
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作者 吴小飞 刘力 +3 位作者 张婉 胡水 金日光 张立群 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期61-63,共3页
A series of fluorescent composites were prepared by blending silicone rubber with Eu(TTA )2(phen)(MA). The influence of mechanical blending temperature on fluorescent intensity of composites and dispersion of rare ear... A series of fluorescent composites were prepared by blending silicone rubber with Eu(TTA )2(phen)(MA). The influence of mechanical blending temperature on fluorescent intensity of composites and dispersion of rare earth complexes in the SiR matrix were investigated. As for the cured rubber, it is found that its fluorescent intensity is relatively low compared with that of uncured rubber. Low temperature is beneficial to dispersion of Eu(TTA )2(phen)(MA) homogeneously. When the amount of rare earth complexes is low, the fluorescent intensity of composites prepared by mechanical blending method above melting point of Eu(TTA )2(phen)(MA) is much higher than that of composites prepared below melting point. 展开更多
关键词 rare earth complex mechanical blending temperature fluorescence property silicon rubber
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Synthesis,Structure and Fluorescent Property of a New Isolated Zn6Co9 Heteronuclear Cluster Constructed by Four Kinds of Ligands 被引量:3
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作者 张光辉 卢久富 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第11期1666-1672,共7页
A novel zero-dimensional heteronuclear cluster based on N-(phosphonomethyl)imi- no-diacetic acid (H4PMIDA) and Phen (1,10-phenanthroline), [Zn6Co9(PMIDA)6(Phen)6(NO3)4(H2O)6]·2NO3·16H2O, has be... A novel zero-dimensional heteronuclear cluster based on N-(phosphonomethyl)imi- no-diacetic acid (H4PMIDA) and Phen (1,10-phenanthroline), [Zn6Co9(PMIDA)6(Phen)6(NO3)4(H2O)6]·2NO3·16H2O, has been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectrum, thermal analysis, and single-crystal X-ray diffraction. The isolated 15- nuclearity cluster [Zn6Co9(PMIDA)6(Phen)6(NO3)4(H2O)6]^2+ was constructed by four kinds of ligands, and its charges are balanced by NO3^–. Each isolated cluster is further extended into a 3D supramolecular network through π???π interaction and C–H…O hydrogen bonds. Moreover, the solid-state fluorescent property of this complex has also been investigated at room temperature. 展开更多
关键词 isolated heteronuclear cluster mixed ligands crystal structure fluorescent property
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Synthesis of Poly (3-acetylpyrrolyl methine) with Azobenzene Side Groups and Study on Its Third-order Nonlinear Optical Property 被引量:4
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作者 Zhigang ZHANG Hongcai WU +1 位作者 Lingjie MENG Wenhui YI 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第5期715-718,共4页
A novel soluble π-conjugated polymer, poly [(3-acetylpyrrole-2, 5-diyl) p-(N, N-dimethylamino) azobenzylidene] (PAPDMAABE), was synthesized by condensation of 3-acetylpyrrole with 4-aldehyde-4'-dimethylaminoaz... A novel soluble π-conjugated polymer, poly [(3-acetylpyrrole-2, 5-diyl) p-(N, N-dimethylamino) azobenzylidene] (PAPDMAABE), was synthesized by condensation of 3-acetylpyrrole with 4-aldehyde-4'-dimethylaminoazobenzene (ADMAA). The chemical structure of PAPDMAABE was characterized by Fourier transform infrared spectroscopy (FTIR), ^1H-NMR, and UV-Vis-NIR spectra. Transmission electron microscope (TEM) analysis for PAPDMAABE indicates that part of PAPDMAABE is in crystal state, due to the short-range order of the polymer. Thermogravimetric analysis (TGA) curve shows that the polymer has good thermal stability and its decomposition temperature is 248℃. The optical band gap of PAPDMAABE obtained from the optical absorption spectrum is about 1.73 eV. The resonant third-order nonlinear optical property of PAPDMAABE at 532 nm was studied using degenerate four-wave mixing (DFWM) technique. The resonant third-order nonlinear optical susceptibility of the polymer is about 7.48×10^-8 esu. 展开更多
关键词 Poly [(3-acetylpyrrole-2 5-diyl) p-(N N-dimethylamino) azobenzylidene] Small optical band gap Degenerate four-wave mixing Third-order nonlinear property
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Impacts of solid physical properties on the performances of a slurry external airlift loop reactor integrating mixing and separation 被引量:2
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作者 Tian Zhang Qingshan Huang +3 位作者 Shujun Geng Aqiang Chen Yan Liu Haidong Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第3期1-12,共12页
Solid physical properties are vital for the design, optimization, and scale-up of gas–liquid–solid multiphase reactors. The complex and interactional effects of the solid physical properties, including particle diam... Solid physical properties are vital for the design, optimization, and scale-up of gas–liquid–solid multiphase reactors. The complex and interactional effects of the solid physical properties, including particle diameter, density, wettability, and sphericity, on the hydrodynamic behaviors in a new external airlift loop reactor(EALR) integrating mixing and separation are decoupled in this work. Two semi-empirical equations are proposed and validated to predict the overall gas holdup and liquid circulating velocity satisfactorily, and then the individual influence of such solid physical properties is further investigated. The results demonstrate that both the overall gas holdup in the riser and the liquid circulating velocity in the downcomer increase with the contact angle, but decrease with particle size, density, and sphericity.Additionally, the impact of the particle size on the liquid circulating velocity is also profoundly revealed on a micro-level considering the particle size distribution. Moreover, the axial solid concentration distribution is discussed, and the uniformity of the slurry is described by the mixing index of the solid particles. The results show that a more homogeneous mixture can be achieved by adding finer particles other than attaining violent turbulence. Therefore, this work lays a foundation for the design, scale-up, and industrialization of the EALRs. 展开更多
关键词 Slurry reactor HYDRODYNAMICS Particle mixing Solid physical property
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Effects of Blending Routes on the Morphology and Properties of PA-6/Nano-CaCO_3/MA-POE Ternary Composites 被引量:1
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作者 NaFENG RuiHUANG +2 位作者 ShenglingJIANG JunlongLIU ChunMA 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第2期261-264,共4页
The effect of blending routes on the morphology and properties of Polyamide-6 (PA-6)/nano-CaCO3/Maleated ethylene-octane copolymer (MA-POE) ternary composite was analyzed using static mechanical test (DMA), TEM (trans... The effect of blending routes on the morphology and properties of Polyamide-6 (PA-6)/nano-CaCO3/Maleated ethylene-octane copolymer (MA-POE) ternary composite was analyzed using static mechanical test (DMA), TEM (transmission electronic microscope) and SEM (scanning electron microscope). It was found that MA-POE, as an impact modifier, had a profound effect upon the toughness of the PA-6/nano-CaCO3 composite. In particular, by adopting two-stage blending route, the microstructure of the ternary composites turned to core-shell structure, and the impact toughness was improved greatly. At the same time, tensile strength and dynamic storage modulus (E1) were higher than those with one-stage blending route processed ternary composite. The results suggest that blending routes may improve the properties of PA-6/nano-CaCO3/MA-POE ternary composites. 展开更多
关键词 blending routes Polyamide-6/nano-CaCO3 Maleated ethylene-octane copolymer property MORPHOLOGY
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Model Analysis of Influences of Aerosol Mixing State upon Its Optical Properties in East Asia 被引量:1
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作者 韩霄 张美根 +1 位作者 朱凌云 许丽人 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第4期1201-1212,共12页
The air quality model system RAMS (Regional Atmospheric Modeling System)-CMAQ (Models-3 Com- munity Multi-scale Air Quality) coupled with an aerosol optical/radiative module was applied to investigate the impact o... The air quality model system RAMS (Regional Atmospheric Modeling System)-CMAQ (Models-3 Com- munity Multi-scale Air Quality) coupled with an aerosol optical/radiative module was applied to investigate the impact of different aerosol mixing states (i.e., externally mixed, half externally and half internally mixed, and internally mixed) oil radiative forcing in East Asia. The simulation results show that the aerosol optical depth (AOD) generally increased when the aerosol mixing state changed from externally mixed to internally mixed, while the single scattering albedo (SSA) decreased. Therefore, the scattering and absorption proper- ties of aerosols can be significantly affected by the change of aerosol mixing states. Comparison of simulated and observed SSAs at five AERONET (Aerosol Robotic Network) sites suggests that SSA could be better estimated by considering aerosol particles to be internally mixed. Model analysis indicates that the impact of aerosol mixing state upon aerosol direct radiative forcing (DRF) is complex. Generally, the cooling effect of aerosols over East Asia are enhanced in the northern part of East Asia (Northern China, Korean peninsula, and the surrounding area of Japan) and are reduced in the southern part of East. Asia (Sichuan Basin and Southeast China) by internal mixing process, and the variation range can reach +5 W m 2. The analysis shows that the internal mixing between inorganic salt and dust is likely the main reason that the cooling effect strengthens. Conversely, the internal nfixture of anthropogenic aerosols, including sulfate, nitrate, ammonium, black carbon, and organic carbon, could obviously weaken the cooling effect. 展开更多
关键词 aerosol optical properties internal mixing state direct radiative forcing CMAQ
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Study on Relationship Between the Size Distribution of Glutenin Polymeric Protein and Wheat Flour Mixing Properties 被引量:1
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作者 Daryl Mares 《Agricultural Sciences in China》 CAS CSCD 2002年第2期138-142,共5页
Parental varieties Suneca and Cook have contrasting alleles at each of the five glutenin subunit loci (Glu-B1, Glu-D1 Glu-A3, Glu-B3, and Glu-D3), a set of 60 lines homozygous at these loci from the F4 progeny populat... Parental varieties Suneca and Cook have contrasting alleles at each of the five glutenin subunit loci (Glu-B1, Glu-D1 Glu-A3, Glu-B3, and Glu-D3), a set of 60 lines homozygous at these loci from the F4 progeny population of Suneca X Cook was chosen to analyze the variation of the size distribution of glutenin polymeric protein (measured by SE-HPLC) and flour mixing properties of these lines and to study relationship between the size distribution of glutenin polymeric protein and wheat flour mixing properties. The results showed that there were very significant differences among the relative size distributions of glutenin polymeric protein (i.e. percentage of unextracTable polymeric protein in the total polymeric protein, or UPP%) and dough development times (i.e. peak time of mixograph, or PTM) of different homozygous lines, respectively. Flour mixograph shape was closely related to UPP% value. The results also indicated that UPP% was very strongly positive correlation with PTM and negative correlation with peak height of mixograph (PHM). Comparing with flour protein content (FP%), UPP% gave greater effect on PTM and PHM, i.e. flour mixing properties, and it can be considered as one of criteria for quality selecting from early generation of breeding program. 展开更多
关键词 WHEAT Glutenin polymer Size distribution mixing properties
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Hydrothermal Synthesis, Crystal Structure and Magnetic Property of a Novel Mixed Valence Decatungstate: [Cu(2,2′-bipy)_2]_2Na_2W_6~VW4^(VI)O_(30)·2H_2O 被引量:1
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作者 李涛海 吕健 +1 位作者 高水英 曹荣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第1期57-62,共6页
A novel Cu(II)-2,2'-bipy-supported (bipy = bipyridine) mixed valence decatungstate, [Cu(2,2'-bipy)2]2Na2W6^VW4^VIO30·2H2O 1, has been synthesized and structurally characterized by X-ray analysis. The crys... A novel Cu(II)-2,2'-bipy-supported (bipy = bipyridine) mixed valence decatungstate, [Cu(2,2'-bipy)2]2Na2W6^VW4^VIO30·2H2O 1, has been synthesized and structurally characterized by X-ray analysis. The crystal of 1 is of triclinic, space group P1^- with a= 10.9393(10), b = 12.0492(2), c = 12.3783(2)A, a = 80.631(10), β= 70.226(10), γ= 72.329(9)^o, V = 1459.64(4)A^3, Z = 1, Dc = 3.582 g/cm^3, F(000) = 1404, R = 0.0553 and wR = 0.1242 for 4607 observed reflections (I 〉 2σ(I)). The EPR spectrum of 1 indicates that its unpaired electrons are placed in the dx2-y2 orbital of the ground state of Cun. Furthermore, compound 1 shows an antiferromagnetic interaction. 展开更多
关键词 crystal structure DECATUNGSTATE mixed valence magnetic property
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