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Defence Technology（防务技术） 2019年第5期15卷 674-679页

作者： Yan-jie Ni Yong jin Gang Wan Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094JiangsuChina China Academy of Ordnance 100089BeijingChina

An axisymmetric two-dimensional(2D)internal ballistic model including the transient burning rate law is used to simulate the 30mm electrothermal-chemical(ETC)launch with the discharge rod plasma generator(DRPG).The relationship between the pressure wave and the initial parameters,such as input electric power,discharging timing sequence,loading density and propellant web thickness,is researched through the change of initial parameters in the *** the condition of synchronous discharging,the maximum of the pressure wave can be controlled while the ratio of the input electric energy to the propellant chemical energy(electric energy ratio)is less than *** the electric energy ratio is larger than 0.11,the maximum of the pressure wave increases rapidly with the electric energy *** the increasing of the electric energy ratio,the change of the first negative amplitude value can be *** the condition of timing sequence discharging,the allowed input electric energy ratio to control the pressure wave is proportional to the current pulse *** the high electric energy ratio,the maximum of the pressure wave is inverse proportional to the current pulse *** pressure wave increases with the increasing of the loading *** the allowed electric energy ratio to control the pressure wave and the variation trend of the first negative amplitude wave value doesn't *** the discharging of the DRPG,the influence of changing propellant web thickness in ETC launch can be ignored.

关键词： Electrothermal-chemical launch Pressure wave Plasma Solid propellant Electric energy ratio

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石油树脂加氢研究进展

高分子通报 2024年第7期37卷 904-916页

作者：牛彤时正阳孙锦昌张谦温北京石油化工学院新材料与化工学院北京102617

石油树脂是以石油化工过程中的特定馏分聚合而成的有机聚合物,是高分子材料开发和性能改进的重要原料,通常因其色度深、气味重、耐温耐候性差等问题致使应用场景受限。石油树脂加氢改性可优化各项物化性能,推动其在高附加值产品行业领... 详细信息

石油树脂是以石油化工过程中的特定馏分聚合而成的有机聚合物,是高分子材料开发和性能改进的重要原料,通常因其色度深、气味重、耐温耐候性差等问题致使应用场景受限。石油树脂加氢改性可优化各项物化性能,推动其在高附加值产品行业领域中应用,实现高档氢化石油树脂的高效生产已成为当下的研究焦点。本文总结了石油树脂的特性与分类,阐述了各类加氢工艺技术特点,全面分析了石油树脂加氢机理及催化剂与载体改性机理,提出提高催化剂性能的可能途径和方向。

关键词：石油树脂加氢催化剂活性机理载体改性

Trace element and Nd isotope analyses of apatite in granitoids and metamorphosed granitoids from the eastern Central Asian Orogenic Belt:Implications for petrogenesis and post-magmatic alteration

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Geoscience Frontiers 2023年第2期14卷 71-85页

作者： Xin-Yu Long Jie Tang Wen-Liang Xu Chen-Yang Sun jin-Peng Luan Shuai Xiong Xiao-ming zhang College of Earth Sciences Jilin UniversityChangchun 130061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural Resources of ChinaChangchun 130061China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang 110819China State Key Laboratory of Superhard Materials Jilin UniversityChangchun 130012China

We present in situ trace element and Nd isotopic data of apatites from metamorphosed and metasomatized(i.e.,altered)and unaltered granitoids in the Songnen and Jiamusi massifs in the eastern Central Asian Orogenic Belt,with the aim of fingerprinting granitoid petrogenesis,including both the magmatic and post-magmatic evolution *** from altered granitoids(AG)and unaltered granitoids(UG)are characterized by distinct textures and geochemical *** from AG have irregular rim overgrowths and complex internal textures,along with low contents of rare earth elements(REEs),suggesting the re-precipitation of apatite during epidote crystallization and/or leaching of REEs from apatite by metasomatic ***(t)values of the these apatites are decoupled from zircon eHf(t)values for most samples,which can be attributed to the higher mobility of Nd as compared to Sm in certain *** from UG are of igneous origin based on their homogeneous or concentric zoned textures and coupled Nd-Hf isotopic *** element variations in igneous apatite are controlled primarily by the geochemical composition of the parental melt,fractional crystallization of other REEbearing minerals,and changes in partition *** contents and Eu/Eu^(*) values of apatites from UG correlate with whole-rock Sr and SiO2 contents,highlighting the effects of plagioclase fractionation during magma *** from UG can be subdivided into four groups based on REE *** 1 apatites have REE patterns similar to the host granitoids,but are slightly enriched in middle REEs,reflecting the influence of the parental melt composition and REE *** 2 apatites exhibit strong light REE depletions,whereas Group 3 apatites are depleted in middle and heavy REEs,indicative of the crystallization of epidote-group minerals and hornblende before and/or during apatite crystallization,*** 4 apatites are depleted in heavy REEs,but e

关键词： Eastern CAOB Granitoid petrogenesis Apatite geochemistry Fluid-induced alteration Nd-Hf isotopic decoupling Crustal assimilation

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机器视觉判别牛肉新鲜度的多模型定量分析

食品与发酵工业 2024年第8期50卷 262-270,277页

作者：陆钟超邱月张安强张建友崔蓬勃翔云金霞吕飞浙江工业大学食品科学与工程学院浙江杭州310014 浙江工业大学网络空间安全研究院浙江杭州310014 杭州冠华王食品有限公司浙江杭州310014

色泽是判断生鲜牛肉新鲜度的重要指标之一。随着人工智能的发展,机器视觉为生鲜肉新鲜度判别提供了可量化的解决方案。该研究通过智能手机获取牛肉图像,利用灰度化、二值化、图像分割与提取,获取不同新鲜度牛肉图像在Red-Green-Blue(RGB... 详细信息

色泽是判断生鲜牛肉新鲜度的重要指标之一。随着人工智能的发展,机器视觉为生鲜肉新鲜度判别提供了可量化的解决方案。该研究通过智能手机获取牛肉图像,利用灰度化、二值化、图像分割与提取,获取不同新鲜度牛肉图像在Red-Green-Blue(RGB)、L^(*)a^(*)b^(*)和Hue-Saturation-Intensity(HSI)颜色空间的颜色参数,并与常规牛肉新鲜度评价指标挥发性盐基氮(total volatile base nitrogen,TVB-N)、硫代巴比妥酸(thiobarbituric acid,TBA)、菌落总数(total viable count,TVC)和感官评分(sensory index,SI)相关联,建立多元线性回归(multiple linear regression,MLR)、反向传播神经网络(back propagation neural network,BPNN)和支持向量回归(support vector regression,SVR)牛肉新鲜度定量预测模型。结果表明,MLR模型对TVB-N、TBA、TVC和SI值的预测模型决定系数(R^(2))分别为0.9406、0.9316、0.9582和0.9548。BPNN模型R^(2)为0.9627、0.9641、0.9920和0.9864,SVR模型的R^(2)为0.9712、0.9679、0.9928和0.9883。3种模型中SVR模型新鲜度预测性能最优,且预测相对误差均在±10%之内。在此基础上,建立了基于颜色参数的SVR牛肉货架期预测模型(R^(2)=0.9648),该模型的预测值与真实货架期平均绝对误差<0.5 d,优于传统货架期模型,提供了一种无损、快速确定牛肉新鲜度和货架期的新方法。

关键词：机器视觉牛肉检测新鲜度指标颜色参数支持向量回归货架期

Elimination of Surfactants and Small Dyes from Water with Silicasupported Dendritic Amphiphiles

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Chinese Journal of Polymer Science 2016年第1期34卷 59-68页

作者： Feng Chen 万德成 ming jin Hong-ting Pu Institute of Functional Polymers School of Materials Science and EngineeringTongji UniversityShanghai 201804China Key Laboratory of Advanced Civil Engineering Materials(Tongji University) Ministry of EducationShanghai 201804China

Silica-supported branched polyethylenimine（Sil@PEI） is a conventional adsorbent and shows a limited affinity to anionic surfactants and small dyes（K = 106？107 L/mol）. If the PEI is alkylated with cetyl groups（C16）, the K of the resulting adsorbents（Sil@PEI@C16-x, where x is the fraction of PEI units being alkylated） is significantly improved. Optimization shows that Sil@PEI@C16-0.15 can best reduce aqueous surfactants to a residue around 10？10 mol/L; while Sil@PEI@C16-0.6 can reduce even small aqueous dyes to a residue below 10？10 mol/L, nearly 105-fold lower than that by Sil@PEI. The adsorbents are well recyclable. It is believed that in the case of dyes, the dense cetyl shell can isolate the PEI from the bulky water and thus suppress the competitive binding by water; while in the case of surfactants, the semiclosed cetyl shell can simultaneously meet electrostatic complement and hydrophobic complement to the surfactants.

关键词： Dendritic amphiphile Water treatment Adsorbent Micropollutant Support

基于ISM-MICMAC的建筑业碳减排影响因素分析

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沈阳建筑大学学报（社会科学版） 2024年第1期26卷 64-70页

作者：张德海金明珠张雨沈阳建筑大学管理学院辽宁沈阳110168

通过查阅与梳理相关文献,从政策、经济、技术、组织4个方面归纳了与建筑业碳减排相关的17个影响因素。基于解释结构模型(Interpretative Structural Modeling, ISM)构建了多级递阶结构模型,揭示了各影响因素相互作用的逻辑关系;运用交... 详细信息

通过查阅与梳理相关文献,从政策、经济、技术、组织4个方面归纳了与建筑业碳减排相关的17个影响因素。基于解释结构模型(Interpretative Structural Modeling, ISM)构建了多级递阶结构模型,揭示了各影响因素相互作用的逻辑关系;运用交叉影响矩阵相乘法(Matriced′Impacts Croises-Multiplication Appliance Classement, MICMAC)分析了各影响因素的相互影响与依赖关系,以此进一步识别出在建筑业碳减排领域中需要重点关注的影响因素,并有针对性地提出了相关建议,以期为建筑业的低碳发展提供参考。

关键词：碳减排影响因素 ISM MICMAC

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Simulation of drop breakage in liquid–liquid system by coupling of CFD and PBM: Comparison of breakage kernels and effects of agitator configurations

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Chinese Journal of Chemical Engineering 2019年第5期27卷 1001-1014页

作者： Rui Xie Jun Li Yang jin Da Zou ming Chen Department of Chemical Engineering Sichuan University

This work focuses on drop breakage for liquid-liquid system with an adoption of numerical simulation by using computational fluid dynamics and population balance model (PBM) coupled with two-fluid model (TFM). Two different breakage kernels based on identical breakage mechanism but different descriptions of breaking time are take n into account in this work. Eight cases corresp on ding to distinct configurations of agitator are carried out to validate numerical predictions, namely agitators with different porosity and hole diameters, respectively implemented in Cases 1 to 5 and Cases 6 to 8. The results are compared with experimental data for testing the applicability of both kernels. Simulations are implemented, in this work, with an approach of class method for the solution of population balance model by the special-purpose computational fluid dynamics solver Fluent 16.1 based on finite volume method, and the grids used for meshing the solution domain are accomplished in a commercial software Gambit 2.4.6. The effects of configurations of agitator corresponding to different parameters mentioned above on final Sauter mean diameter are equally concentrated in this work. Analysis of both kernels and comparisons with experimental results reveal that, the second kernel has more decent agreement with experiments, and the results of investigations on effects of agitator configurations show that the in fluences of these parameters on Sauter mean diameter are marginal, but appropriate porosity and hole diameter are actually able to decrease Sauter mean diameter. These outcomes allow us to draw general conclusions and help investigate performances of liquid-liquid system.

关键词： Stirred vessel Liquid-liquid system Computational fluid dynamics Population balance model Breakage kernel Agitator configuration

INFLUENCE OF THE SCORER PARAMETER PROFILE ON THE WAVELENGTH OF TRAPPED LEE WAVES

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Journal of Hydrodynamics 2007年第2期19卷 165-172页

作者： ZANG Zeng-liang zhang ming HUANG Hong Department of Martial Meteorology Institute of Meteorological PLA University of Science and TechnologyNanjing 211101 China State Key Laboratory of Atmospheric Sciences and Geophysical Fluid Dynamics Institute of AtmosphericPhysics Chinese Academy of Sciences Beijing 100029 China

A three-layer theoretical model was established, in which the atmosphere is divided into three layers based on the Scorer parameter 12 , which is large in the middle layer and small in the other two layers. The wave number formula of lee waves was deduced with this theoretical model, and a typical example for the lee wave was calculated. Thus, the influence of changes in the thickness of every layer and values of the Scorer parameter in every layer was examined. The results show that the wavelength decreases with an increase in the thickness of the lower and the middle layers and is more sensitive to the changes in the middle layer. Therefore, if the changes in these two layers are different, the changes in the middle layer will dominate the changes in the wavelength. The results also show that the wavelength decreases with the increase in the value of 12 in every layer, among which the sensitivity to the 12 in the upper layer is the most striking. The calculation results reasonably can explain the influence of diurnal changes on the wavelength. The example was simulated using Advanced Regional Prediction System model, and the sensitivity experiments were performed to confirm the effects of the Scorer parameter profiles on the wavelengths. The simulated results are consistent with the calculated results.

关键词： lee waves Scorer parameter three-layertheoretical model wavelength

具有鲁棒性机械性能和高弹性的超长室温磷光共价有机框架弹性体

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高分子学报 2024年第6期55卷 709-717页

作者：徐静陈天泽邵明超郭云龙张新瑞王廷梅先进润滑与防护材料研究发展中心、中国科学院兰州化学物理研究所兰州730000 北京分子科学国家研究中心、中国科学院化学研究所、中国科学院有机固体重点实验室北京100190 中国科学院大学北京100049

开发具有持久稳定室温磷光的弹性体材料是柔性电子学和光子学领域的一大挑战.本文报到了一种高度可拉伸、高机械强度且可持续发光的室温磷光共价有机框架弹性体(SPU-D230-UPy COF)材料.该材料由烷基链软段与含多重氢键硬段限域共价有机... 详细信息

开发具有持久稳定室温磷光的弹性体材料是柔性电子学和光子学领域的一大挑战.本文报到了一种高度可拉伸、高机械强度且可持续发光的室温磷光共价有机框架弹性体(SPU-D230-UPy COF)材料.该材料由烷基链软段与含多重氢键硬段限域共价有机框架而组成,展现出高的机械性能和高弹性.在除去365 nm的激发后,具有明亮且持续的室温磷光发射特性(发光时间持续3.0 s).力学研究表明,其具备约33.5 MPa的强度、约188.26 MJ/m3的优异韧性以及约76.6 MPa的杨氏模量.同时该弹性体即使经历反复的机械变形也能保持优异的光学性能.本研究为发光弹性体在可穿戴设备、柔性显示器和防伪设备等方面的应用奠定了基础.

关键词：弹性体共价有机框架超长室温磷光多重氢键

数据驱动的混凝土材料-结构一体化设计研究进展

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建筑结构学报 2024年第8期45卷 20-33页

作者：胡张莉刘加平赵羽习赵海涛戚家南王育江韩方玉金鸣东南大学材料科学与工程学院江苏南京211102 浙江大学建筑工程学院浙江杭州310058 河海大学土木与交通学院江苏南京210024 东南大学土木工程学院江苏南京211102 江苏省建筑科学研究院有限公司江苏南京210024

材料-结构一体化设计是指在结构设计中综合考虑材料的性能,而在材料设计中则以结构的需求为出发点,形成材料到结构跨多尺度的设计模式,近年来已成为现代混凝土工程领域的研究重点。基于数据及人工智能算法的混凝土材料、结构设计方法可... 详细信息

材料-结构一体化设计是指在结构设计中综合考虑材料的性能,而在材料设计中则以结构的需求为出发点,形成材料到结构跨多尺度的设计模式,近年来已成为现代混凝土工程领域的研究重点。基于数据及人工智能算法的混凝土材料、结构设计方法可颠覆传统设计依赖经验且需重复试配的范式,实现高效节材及结构创新。梳理了国内外混凝土材料智能设计及材料-结构一体化设计的研究现状,总结了材料层面数据驱动的正向预测及逆向设计的研究范畴和关键问题,梳理了考虑温-湿-约束复杂交互的材料-结构一体化抗裂设计途径与效果,以氯盐侵蚀环境为例分析了混凝土材料-结构耐久性设计方案及提升手段,并以超高性能混凝土为例阐述了混凝土材料-结构高性能设计的方法,提出未来数据驱动的混凝土材料-结构一体化设计框架及生产、设计、制备及结构应用全综合的研究思路,并建议未来应在数据库建设、数据与理论融合及多尺度关联的协同算法等方面开展研究。

关键词：材料-结构一体化设计数据驱动抗裂耐久性高性能