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SYNTHESIS AND SIZING PROPERTIES OF GRAFT STARCHES AS WARP SIZING MATERIALS FOR POLYESTER/COTTON BLEND SPUN YARN 被引量:4
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作者 祝志峰 周永元 张文赓 《Journal of China Textile University(English Edition)》 EI CAS 1994年第1期22-30,共9页
Grafting a number of monomers such as acrylic acid, acrylamide, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, butyl methacrylate and vinyl acetate onto granular corn starch was carried out resp... Grafting a number of monomers such as acrylic acid, acrylamide, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, butyl methacrylate and vinyl acetate onto granular corn starch was carried out respectively in aqueous dispersion by using cerie ammonium nitrate as an initiator under nitrogen atmosphere. Conversion of monomer, grafting ratio and grafting efficiency were measured by the method of combining the chemical quantitative analysis with the weight. The adhesive power of the starch graft copolymers to polyester/cotton fiber was evaluated by measuring the breaking strength and elongation of the roving impregnated with the paste. The viscosity change of the size paste before and after grafting was studied. The mechanical properties of polyester/cotton fibre yarn sized by the graft starch were tested. The main conclusions are as follows: (1) monomers which were graft coplymerized onto starch have a significant influence upon the viscosity of the size paste; (2) the adhesive power 展开更多
关键词 STARCH GRAFT warp size sizing Modification
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Effect of Starch Dodecenylsuccinylation on the Adhesion and Film Properties of Dodecenylsuccinylated Starch for Polyester Warp Sizing 被引量:5
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作者 李长龙 鲍乐 祝志峰 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期747-752,共6页
A series of dodecenylsuccinylated starches( DSSs) with different degree of substitution( DS) were prepared via the esterification of dodencenylsuccinic anhydride with hydrolyzed cornstarch in aqueous dispersion for in... A series of dodecenylsuccinylated starches( DSSs) with different degree of substitution( DS) were prepared via the esterification of dodencenylsuccinic anhydride with hydrolyzed cornstarch in aqueous dispersion for investigating the influences of starch dodecenylsuccinylation upon the performances such as apparent viscosity and surface tension of starch paste, film behaviors,and adhesion to fibers for warp sizing. It was found that the dodecenylsuccinylation was able to reduce the surface tension of cooked starch paste and enhance the adhesion of starch to polyester fibers. It was also capable of depressing the brittleness of native starch and improving the mechanical behaviours such as breaking elongation and work-to-break of starch film. Initial increase in DS level of dodecenylsuccinylation enhanced these positive effects,while excessively increasing the level resulted in marked reduction in tensile strength of starch film and significant decrement in reaction efficiency. X-ray diffraction patterns of starch films showed the dodecenylsuccinates derivatized onto the backbones of starch depressed the degree of crystallinity of starch film. Based on the paste behaviors, adhesion, and film properties, the dodecenylsuccinylation level is recommended in a range of 0. 015-0. 025 for sizing polyester warps. 展开更多
关键词 warp sizing agent esterified starch dodecenylsuccinylation ADHESION film behaviour
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Synthesis and Performances of Poly(2-ethylhexyl acrylate-co-acrylic acid) Used for Warp Sizing
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作者 祝志峰 高林林 +1 位作者 王其 乔志勇 《Journal of Donghua University(English Edition)》 EI CAS 2011年第5期511-515,共5页
A series of poly ( 2-ethylhexyl acrylate-co-acrylic acid ) s ( P (2-EHA-co-AA) )s with different mole contents of 2-ethylhexyl acrylate ( 2-EHA ) were synthesized through free radical copolymerization in ethan... A series of poly ( 2-ethylhexyl acrylate-co-acrylic acid ) s ( P (2-EHA-co-AA) )s with different mole contents of 2-ethylhexyl acrylate ( 2-EHA ) were synthesized through free radical copolymerization in ethanol for investigating the influences of copolymer composition upon the performance such as apparent viscosity, film behaviors, and adhesion to fibers for warp sizing. The content of 2-EHA was varied from 80 % to 40 %. The adhesion was estimated by measuring tensile strength and work-to-break of impregnated roving. The film behaviors were evaluated in terms of breaking strength, breaking elongation, work-to-break, and flex- fatigue resistance. It was observed that the viscosity, adhesion, and film behaviors of the copolymers strongly depended on the content of 2-EHA. Excessively increasing or decreasing the content of 2-EHA units incorporated into the copolymeric chains reduces the serviceability of P(2-EHA-co-AA) in warp sizing. The adhesion and film behaviors of the copolymcr reach their maximal values at mole content of 50 % simultaneously. Therefore, the copolymer used as sizing agent should be synthesized under equal mole of 2-EHA and AA in monomer formulation. 展开更多
关键词 warp sizing agents 2-ethylhexyl acrylate copolymer copolymer composition ADHESION film behavior
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Starch Modifications to Improve the Paste Stabilities Both in Phase and Viscosity for Warp Sizing 被引量:3
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作者 祝志峰 於洁 喻翠云 《Journal of Donghua University(English Edition)》 EI CAS 2005年第2期13-18,共6页
An attempt has been made to improve the paste stabilities both in viscosity of a hot starch paste and in phase of a starch-polyvinyl alcohol blend paste for warp sizing. The phase stability was evaluated in terms of t... An attempt has been made to improve the paste stabilities both in viscosity of a hot starch paste and in phase of a starch-polyvinyl alcohol blend paste for warp sizing. The phase stability was evaluated in terms of the initial demixing time, and the volume percentage of polyvinyl alcohol separated. It was found that starch cross-linking is harmful to the phase stability of a starch-polyvinyl alcohol blend paste no matter what a type of polyvinyl alcohol is used, although the cross-linking is an effective technique for stabilizing the viscosity of a hot starch paste. The separation rate and extent all increase with the increase in the cross-linking degree of starch. However, this defect can be eliminated through introducing quaternary ammonium groups into crosslinked starch molecules. Evident effect can be achieved when the degree of substitution is as less as 0.021. Generally, increase in the DS reduces the separation rate and extent, and thereby raising the phase stability. Moreover, the effects of both starch content and PVA type on the separation are also considered. Cationization after starch cross-linking shows improved stabilities both in viscosity and phase. 展开更多
关键词 STARCH polyvinyl alcohol paste stability phase stability warp sizes
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Effect of Structural Units on the Adhesion of Acrylic Copolymers to Fibers for Warp Sizing 被引量:1
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作者 祝志峰 许德生 徐珍珍 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期825-829,共5页
Radical copolymerization of acrylic acid(AA)with acrylamide(AM)or acrylamide/acrylonitrile(AM/AN)was initiated with ammonium persulfate as initiator to produce acrylic copolymers such as bicopolymer poly(AM-co-AA)and ... Radical copolymerization of acrylic acid(AA)with acrylamide(AM)or acrylamide/acrylonitrile(AM/AN)was initiated with ammonium persulfate as initiator to produce acrylic copolymers such as bicopolymer poly(AM-co-AA)and tercopolymer poly(AM-co-AN-co-AA)for revealing the effects of the structural units of the copolymers on the adhesion of the copolymers to polyester or cotton fibers for warp sizing.The adhesion was evaluated in terms of tensile strength and work-to-break of a roving impregnated with the copolymer solution.It was found that the adhesion strongly depended on type and amount of the units incorporated into the copolymeric chains.Whether the fiber is cotton or polyester,the adhesion of the bicopolymer poly(AM-co-AA)is greater than that of polyacrylic acid or polyacyamide.Excessively increasing the amount of AM or AA unit in poly(AM-co-AA)lowers the adhesion.To enhance the adhesion of the bicopolymer,a favorable mole ratio of AM to AA is 70/30.Based on this mole ratio,incorporation of acrylonitrile units into poly(AM-co-AA)to form tercopolymer enhances the adhesion. 展开更多
关键词 acrylic copolymers warp sizes structural units ADHESION
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Effect of Carboxymethyl Starch as Stabilizer for Increasing the Stability of Warp Sizing Pastes
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作者 祝志峰 梁茵 《Journal of Donghua University(English Edition)》 EI CAS 2003年第2期94-97,共4页
The influences of carboxymethyl starch used as stabilizer upon the stability of native cornstarchpolyvinyl alcohol blend pastes for warp sizing have been investigated. The effect of the modified starch on the paste st... The influences of carboxymethyl starch used as stabilizer upon the stability of native cornstarchpolyvinyl alcohol blend pastes for warp sizing have been investigated. The effect of the modified starch on the paste stability was evaluated in terms of the initial demixing time and the volume percentage of separated starch. The carboxymethyl starch with a series of different degrees of substitution was prepared in ethanol dispersion by varying the amount of monochloroacetic acid reacted with refined native cornstarch. The paste stability strongly depends on the modification extent and amount of carboxymethyl starch used, and on native starch content in the paste. Increase in the modification extent and/or the amount of the modified starch effectively retards the phase separation and reduces the separation extent of native cornstarch-polyvinyl alcohol blend pastes.Moreover, the mechanism and favorable modification extent of carboxymethyl starch for enhancing paste stability are also investigated and discussed. 展开更多
关键词 warp sizes paste stability carboxymethyl starch polyvinyl alcohol STARCH
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Study on the Preparation of Allyl-modified Starch in Isopropyl/Water Medium for Warp Sizing
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作者 李曼丽 祝志峰 张龙秋 《Journal of Donghua University(English Edition)》 EI CAS 2008年第4期400-404,共5页
A new method for the pretreatment of starch by etherification was developed to eliminate the problems of lower grafting efficiency associated with the preparation of starch graft copolymers as warp sizing agents. The ... A new method for the pretreatment of starch by etherification was developed to eliminate the problems of lower grafting efficiency associated with the preparation of starch graft copolymers as warp sizing agents. The etherification of starch with allyl chloride was investigated in order to effectively enhance the reaction efficiency. The tecimological variables of the reaction considered for evaluating the etherification included sodium hydroxide amount, water content in water-isopropyl alcohol medium, allyl chloride concentration, reaction temperature and reaction time. The experimental result demonstrated that the variables considered showed evident effect on the reaction efficiency. For the etherification, a condition of 20% for the water content, 1.5:1 for the molar ratio of sodium hydroxide to allyl chloride, and at 30℃ under 24 h reaction is sufficient to retain the reaction efficiency above 50%. Furthermore, a contrast test demonstrated that the graft efficiency can be increased with the etherification pretreatment. 展开更多
关键词 warp sizes allyl starch etheri fication reaction efficiency
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The Usability of Polyoxyethylene Stearate as Lubricant for Sizing Cotton Warp Yarns
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作者 祝志峰 孟娜 许冬生 《Journal of Donghua University(English Edition)》 EI CAS 2012年第2期162-165,共4页
The usability of polyoxyethylene stearate with 10 ethylene epoxides(POES 10) as lubricant in warp sizing was investigated for replacing sizing cream in order to prevent blockage of paste delivery tube.The influences o... The usability of polyoxyethylene stearate with 10 ethylene epoxides(POES 10) as lubricant in warp sizing was investigated for replacing sizing cream in order to prevent blockage of paste delivery tube.The influences of POES 10 and sizing cream upon the adhesion of starch to fibers and the performances of starch film were measured and compared.Then,the usability of POES 10 as lubricant was evaluated through the comparison between POES 10 and sizing cream in tensile behaviors,abrasion resistance,and hairiness of sized cotton yarns.The experimental observation demonstrates that the influence of POES 10 upon the adhesion is similar to that of sizing cream.POES 10 is superior to sizing cream in tensile strength and breaking elongation of starch film when mass content of lubricants is equal to or exceeds 2%.Incorporating POES 10 into starch makes starch film more resistant to wear.Furthermore,POES 10 is preferred to sizing cream in the increase in tensile strength,loss in elongation,and abrasion resistance of sized cotton yarns.Using POES 10 as lubricant in size formulation is favorable to the decrease of longer hairs on sized yarns.POES 10 exhibits potential use during cotton warp sizing for replacing sizing cream. 展开更多
关键词 polyoxyethylene stearate(POES) LUBRICANT warp sizing additives
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Evaluation of Switched-Reluctance Machine through Generalized Sizing Equations
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作者 Huang Surong Xie Guodong (School of Automation) 《Advances in Manufacturing》 SCIE CAS 1998年第2期33-37,共5页
With the evolution of converter fed machines (CFMs), it becomes important to evaluate the power potential of such machines of vastly different topologies with a variety of waveforms of back emf and current. It is base... With the evolution of converter fed machines (CFMs), it becomes important to evaluate the power potential of such machines of vastly different topologies with a variety of waveforms of back emf and current. It is based on the generalized sizing equations and permits the evaluation of the main dimensions with respect to the power of those machines. In this paper, a general approach is presented to extend the evaluation method of machine power density to the switched reluctance (SR) machine, and furthermore to compare the power production capability between the SR machine and the well known squirrel cage induction machine. 展开更多
关键词 switched reluctance machine converter fed machine sizing equations power density
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Evolution of Generalized Sizing for Evaluation of Converter Fed Machines
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作者 黄苏融 谢国栋 《Advances in Manufacturing》 SCIE CAS 1997年第1期48-54,共7页
Based on the concept of the converter fed machines (CFMs), an optimal machine design can be considered as the best match of the machine topology, the power electronic converter and the performance specifications. To e... Based on the concept of the converter fed machines (CFMs), an optimal machine design can be considered as the best match of the machine topology, the power electronic converter and the performance specifications. To evaluate power production potentials of machines with various topologies with different waveforms of back emf and current, the generalized sizing equations and the power density equation are needed to evaluate the main dimensions and the power of such machines. In this paper. a general approach is presented to develop and to discuss these equations. Sample applications of the generalized sizing and power density equations are utilized to evaluate the induction machine and the double-salient permanent magnet (DSPM) machine. 展开更多
关键词 converter fed machines generalized sizing sizing equation. power density
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Optimization of Power Density for Axial-Flux Machinethrough Generalized Sizing Equations
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作者 黄苏融 谢国栋 《Advances in Manufacturing》 SCIE CAS 1997年第3期232-236,共5页
With the cvolution of various high powerr-density machines, it beeomes important to optimize the power potential of machines of vastly different topologies with a variety of waveforms of back emf and current. The appr... With the cvolution of various high powerr-density machines, it beeomes important to optimize the power potential of machines of vastly different topologies with a variety of waveforms of back emf and current. The approach of tins paper is based oil the gencral-purpose sizing equations. which permit the optinlization method of machine power density to be applied to the axial-flux toroidal permanent-magnet (AFTPM) machine, and,furthermore, the power-production capabilities of the AFTPM machinc and the wen-known squirrel-cage indution machine are compared. 展开更多
关键词 optimization of power density generalized sizing equation axial-flux machine
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Machine learning-assisted microfluidic approach for broad-spectrum liposome size control 被引量:1
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作者 Yujie Jia Xiao Liang +6 位作者 Li Zhang Jun Zhang Hajra Zafar Shan Huang Yi Shi Jian Chen Qi Shen 《Journal of Pharmaceutical Analysis》 2025年第6期1238-1248,共11页
Liposomes serve as critical carriers for drugs and vaccines,with their biological effects influenced by their size.The microfluidic method,renowned for its precise control,reproducibility,and scalability,has been wide... Liposomes serve as critical carriers for drugs and vaccines,with their biological effects influenced by their size.The microfluidic method,renowned for its precise control,reproducibility,and scalability,has been widely employed for liposome preparation.Although some studies have explored factors affecting liposomal size in microfluidic processes,most focus on small-sized liposomes,predominantly through experimental data analysis.However,the production of larger liposomes,which are equally significant,remains underexplored.In this work,we thoroughly investigate multiple variables influencing liposome size during microfluidic preparation and develop a machine learning(ML)model capable of accurately predicting liposomal size.Experimental validation was conducted using a staggered herringbone micromixer(SHM)chip.Our findings reveal that most investigated variables significantly influence liposomal size,often interrelating in complex ways.We evaluated the predictive performance of several widely-used ML algorithms,including ensemble methods,through cross-validation(CV)for both lipo-some size and polydispersity index(PDI).A standalone dataset was experimentally validated to assess the accuracy of the ML predictions,with results indicating that ensemble algorithms provided the most reliable predictions.Specifically,gradient boosting was selected for size prediction,while random forest was employed for PDI prediction.We successfully produced uniform large(600 nm)and small(100 nm)liposomes using the optimised experimental conditions derived from the ML models.In conclusion,this study presents a robust methodology that enables precise control over liposome size distribution,of-fering valuable insights for medicinal research applications. 展开更多
关键词 Liposomes MICROFLUIDICS Liposomal size SHM machine learning
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Impact of Dataset Size on Machine Learning Regression Accuracy in Solar Power Prediction
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作者 S.M.Rezaul Karim Md.Shouquat Hossain +3 位作者 Khadiza Akter Debasish Sarker Md.Moniul Kabir Mamdouh Assad 《Energy Engineering》 2025年第8期3041-3054,共14页
Knowing the influence of the size of datasets for regression models can help in improving the accuracy of a solar power forecast and make the most out of renewable energy systems.This research explores the influence o... Knowing the influence of the size of datasets for regression models can help in improving the accuracy of a solar power forecast and make the most out of renewable energy systems.This research explores the influence of dataset size on the accuracy and reliability of regression models for solar power prediction,contributing to better forecasting methods.The study analyzes data from two solar panels,aSiMicro03036 and aSiTandem72-46,over 7,14,17,21,28,and 38 days,with each dataset comprising five independent and one dependent parameter,and split 80–20 for training and testing.Results indicate that Random Forest consistently outperforms other models,achieving the highest correlation coefficient of 0.9822 and the lowest Mean Absolute Error(MAE)of 2.0544 on the aSiTandem72-46 panel with 21 days of data.For the aSiMicro03036 panel,the best MAE of 4.2978 was reached using the k-Nearest Neighbor(k-NN)algorithm,which was set up as instance-based k-Nearest neighbors(IBk)in Weka after being trained on 17 days of data.Regression performance for most models(excluding IBk)stabilizes at 14 days or more.Compared to the 7-day dataset,increasing to 21 days reduced the MAE by around 20%and improved correlation coefficients by around 2.1%,highlighting the value of moderate dataset expansion.These findings suggest that datasets spanning 17 to 21 days,with 80%used for training,can significantly enhance the predictive accuracy of solar power generation models. 展开更多
关键词 Correlation coefficients dataset size machine learning mean absolute error regression solar power prediction
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Quantitative analysis of laser-generated ultrasonic wave characteristics and their correlation with grain size in polycrystalline materials
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作者 徐兆文 白雪 +2 位作者 马健 万壮壮 王超群 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期526-543,共18页
Quantitative relationship between nanosecond pulsed laser parameters and the characteristics of laser-generated ultrasonic waves in polycrystalline materials was evaluated.The high energy of the pulsed laser with a la... Quantitative relationship between nanosecond pulsed laser parameters and the characteristics of laser-generated ultrasonic waves in polycrystalline materials was evaluated.The high energy of the pulsed laser with a large irradiation spot simultaneously generated ultrasonic longitudinal and shear waves at the epicenter under the slight ablation regime.An optimized denoising technique based on wavelet thresholding and variational mode decomposition was applied to reduce noise in shear waves with a low signal-to-noise ratio.An approach for characterizing grain size was proposed using spectral central frequency ratio(SCFR)based on time-frequency analysis.The results demonstrate that the generation regime of ultrasonic waves is not solely determined by the laser power density;even at high power densities,a high energy with a large spot can generate an ultrasonic waveform dominated by the thermoelastic effect.This is ascribed to the intensification of the thermoelastic effect with the proportional increase in laser irradiation spot area for a given laser power density.Furthermore,both longitudinal and shear wave SCFRs are linearly related to grain size in polycrystalline materials;however,the shear wave SCFR is more sensitive to finer-grained materials.This study holds great significance for evaluating metal material properties using laser ultrasound. 展开更多
关键词 laser-ultrasonics polycrystalline materials ultrasonic time-frequency characteristics grain size
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Micropillar compression using discrete dislocation dynamics and machine learning
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作者 Jin Tao Dean Wei +3 位作者 Junshi Yu Qianhua Kan Guozheng Kang Xu Zhang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第1期39-47,共9页
Discrete dislocation dynamics(DDD)simulations reveal the evolution of dislocation structures and the interaction of dislocations.This study investigated the compression behavior of single-crystal copper micropillars u... Discrete dislocation dynamics(DDD)simulations reveal the evolution of dislocation structures and the interaction of dislocations.This study investigated the compression behavior of single-crystal copper micropillars using fewshot machine learning with data provided by DDD simulations.Two types of features are considered:external features comprising specimen size and loading orientation and internal features involving dislocation source length,Schmid factor,the orientation of the most easily activated dislocations and their distance from the free boundary.The yielding stress and stress-strain curves of single-crystal copper micropillar are predicted well by incorporating both external and internal features of the sample as separate or combined inputs.It is found that the machine learning accuracy predictions for single-crystal micropillar compression can be improved by incorporating easily activated dislocation features with external features.However,the effect of easily activated dislocation on yielding is less important compared to the effects of specimen size and Schmid factor which includes information of orientation but becomes more evident in small-sized micropillars.Overall,incorporating internal features,especially the information of most easily activated dislocations,improves predictive capabilities across diverse sample sizes and orientations. 展开更多
关键词 Discrete dislocation dynamics simulations machine learning Size effects Orientation effects Microstructural features
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激光粒度仪测量上限用毫米级粒度标准物质 被引量:2
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作者 陈胜利 朱秀芹 《中国粉体技术》 CAS 2025年第1期110-117,共8页
【目的】解决我国激光粒度仪测量上限现状不清楚的问题,研制用于判断激光粒度仪测量上限的毫米级颗粒粒度标准物质。【方法】利用悬浮聚合再筛分法制备标称粒径分别为0.6、0.8、1.0、1.1 mm的聚苯乙烯微珠粒度标准物质;利用经NIST SRM2... 【目的】解决我国激光粒度仪测量上限现状不清楚的问题,研制用于判断激光粒度仪测量上限的毫米级颗粒粒度标准物质。【方法】利用悬浮聚合再筛分法制备标称粒径分别为0.6、0.8、1.0、1.1 mm的聚苯乙烯微珠粒度标准物质;利用经NIST SRM2800测微尺校准的光学显微镜对制得的标准物质进行定值。【结果】制得的4种粒度标准物质的体积中位粒径分别为(0.553±0.007)、(0.749±0.008)、(0.925±0.008)、(1.07±0.01)mm;利用制得的粒度标准物质检验了国内外6个公司生产的7种型号激光粒度仪的测量上限,发现只有部分型号的粒度仪能准确测量毫米级粒度标准物质。【结论】制得的毫米级粒度标准物质样品均匀、稳定,粒径定值结果溯源至He-Ne激光波长,准确可靠,使得我国粒度标准物质体系更完善;激光粒度仪测量上限不仅取决于光探测器最内侧单元的半径,还取决于其使用光源的激光质量。 展开更多
关键词 颗粒粒度 标准物质 聚苯乙烯微珠 激光粒度仪 测量上限
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开槽外贴CFRP布-混凝土界面的黏结性能 被引量:2
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作者 高婧 韩泽鸿 +1 位作者 宋怀辉 TERRASI Giovanni 《长安大学学报(自然科学版)》 北大核心 2025年第2期85-95,共11页
为研究混凝土开槽后在凹槽区域外贴碳纤维增强聚合物(CFRP)材料的界面黏结性能,以开槽宽度和深度、混凝土强度等级为主要参数,进行16组开槽外贴CFRP布混凝土试件单剪试验,设置4组未开槽混凝土表面外贴CFRP布试件为对照组;通过分析试验荷... 为研究混凝土开槽后在凹槽区域外贴碳纤维增强聚合物(CFRP)材料的界面黏结性能,以开槽宽度和深度、混凝土强度等级为主要参数,进行16组开槽外贴CFRP布混凝土试件单剪试验,设置4组未开槽混凝土表面外贴CFRP布试件为对照组;通过分析试验荷载-位移曲线、应力分布特点及试件破坏现象,探究试件的极限荷载、黏结强度、最大剪应力、最大滑移量等参数的变化趋势,讨论开槽尺寸和加固方法对试件破坏模式的影响,分析试件的破坏原因及机理;基于试验数据拟合结果建立混凝土开槽外贴CFRP布试件的黏结-滑移模型及最大剪应力计算模型,并将最大剪应力预测结果与文献数据进行对比。研究结果表明:相比于未开槽的加固方法,开槽外贴CFRP布的加固方法能够有效提高混凝土试件黏结界面的极限荷载,试件的破坏模式主要表现为黏结破坏、CFRP布断裂破坏和复合破坏;采用开槽外贴加固(EBROG)方法的试件在凹槽处黏结界面的最大剪应力和峰值滑移随凹槽尺寸的增大而提高,且存在最佳凹槽宽度和深度的组合;提出的最大剪应力计算模型的预测结果与现有文献试验结果的误差在16%之内,该模型可用于预测开槽区域最大剪应力。 展开更多
关键词 桥梁工程 复合材料 黏结性能 开槽外贴加固 CFRP 开槽尺寸
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免退浆工艺对粘胶长丝哈达织物性能的影响
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作者 张昊 刘妍 +2 位作者 胡艳丽 吕学斌 李伟 《现代纺织技术》 北大核心 2025年第7期82-88,共7页
为了探究粘胶长丝哈达织物免退浆工艺的可行性及对织物性能的影响,采用不同比例的复合变性淀粉与PVA-0588混合,探究其配比对浆液粘度、透明度、表面张力的影响,并对浆纱表面形态、上浆率、强力与耐磨等性能进行测试,得到最适宜的浆料配... 为了探究粘胶长丝哈达织物免退浆工艺的可行性及对织物性能的影响,采用不同比例的复合变性淀粉与PVA-0588混合,探究其配比对浆液粘度、透明度、表面张力的影响,并对浆纱表面形态、上浆率、强力与耐磨等性能进行测试,得到最适宜的浆料配方;将其应用在哈达织物的织造中,对免退浆织物与传统上浆工艺织物的力学性能、抗皱性能、弯曲性能及织物风格进行测试分析。结果发现:当复合变性淀粉与PVA的比例为4∶1时,免退浆浆纱的上浆率为3.14%,浆纱强力提高21.19%,耐磨次数也提高到133次;与传统工艺相比,免退浆工艺实现了低上浆率和中低温上浆,免退浆浆纱的性能也得到了较大的提升;该免退浆工艺可用于粘胶长丝哈达织物的生产中,降低成本与能耗。 展开更多
关键词 免退浆工艺 中低温上浆 哈达织物 粘胶长丝 可降解
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超临界二氧化碳制备虾青素脂质体
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作者 刘志军 刘谦 +3 位作者 王荣濠 李志义 刘凤霞 魏炜 《精细化工》 北大核心 2025年第4期872-877,917,共7页
以大豆卵磷脂为载体,利用超临界二氧化碳制备了虾青素脂质体。采用FTIR、TEM、XRD对样品进行了表征。利用纳米粒度及Zeta电位分析仪、紫外-可见分光光度计,考察了制备压力和温度对虾青素脂质体粒径分布、Zeta电位及虾青素包埋率的影响... 以大豆卵磷脂为载体,利用超临界二氧化碳制备了虾青素脂质体。采用FTIR、TEM、XRD对样品进行了表征。利用纳米粒度及Zeta电位分析仪、紫外-可见分光光度计,考察了制备压力和温度对虾青素脂质体粒径分布、Zeta电位及虾青素包埋率的影响。通过体外模拟释放和模拟消化实验评价了虾青素脂质体的虾青素缓释效果。结果表明,在超临界二氧化碳压力20 MPa、50℃的最佳条件下,制备的虾青素脂质体平均粒径为236.0 nm,虾青素包埋率97.18%。经30 d储存后,4和25℃的虾青素脂质体的虾青素保留率分别为94.13%和89.04%;体外释放实验表明,虾青素脂质体具有较好的虾青素缓释效果,在4、12 h的总释放率分别为69.3%和91.0%;体外消化模拟表明,虾青素脂质体在肠道中消化和吸收较强。 展开更多
关键词 超临界二氧化碳 虾青素 脂质体 粒径 包埋率 医药原料
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基于机器学习算法的超声波预测TP2铜材晶粒度模型优化研究
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作者 岳峰丽 郭威 +6 位作者 刘明华 陈大勇 刘劲松 刘欢 宋鸿武 王松伟 褚晓光 《精密成形工程》 北大核心 2025年第9期185-194,共10页
目的借助机器学习算法对超声波衰减系数-平均等效晶粒尺寸模型(AC-AGS)进行优化,以实现高效准确的铜材晶粒尺寸预测。方法通过超声检测设备获得不同温度热处理后的TP2铜材的界面波幅值以及一次底面回波幅值,并通过幅值数据计算衰减系数... 目的借助机器学习算法对超声波衰减系数-平均等效晶粒尺寸模型(AC-AGS)进行优化,以实现高效准确的铜材晶粒尺寸预测。方法通过超声检测设备获得不同温度热处理后的TP2铜材的界面波幅值以及一次底面回波幅值,并通过幅值数据计算衰减系数,采用截点法获得铜材的晶粒尺寸。为优化铜材晶粒尺寸的预测模型,引入3种机器学习优化算法,即粒子群算法(PSO)、遗传算法(GA)以及差分进化算法(DE),对TP2铜材的晶粒度预测模型进行优化。结果耦合机器学习算法的AC-AGS模型可以实现精密铜材平均晶粒尺寸的评测,PSO算法在本文优化结果中表现最佳,其验证结果的决定系数R^(2)为0.9045,均方根误差(Root Mean Square Error,RMSE)为20.85,平均绝对误差(Mean Absolute Error,MAE)为20.569。结论结合机器学习优化算法的超声波衰减系数与平均晶粒尺寸模型,实现了对TP2铜材晶粒尺寸的精确预测。该模型不仅为铜材晶粒尺寸的无损检测提供了一个高效、准确的预测工具,还为其他材料的晶粒尺寸预测提供了新的思路和方法。 展开更多
关键词 机器学习 超声检测 TP2铜材 晶粒度预测 衰减系数
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