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Chinese Journal of Polymer Science 2014年第7期32卷 823-833页

作者： shuang-mei zhang Hui-xian zhang Wei-yi zhang Zhi-qiang Wu Feng Chen 傅强 College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science Fudan University

In this study, four hydroxyl-terminated polydimethylsiloxanes （PDMSOH） with different viscosities and hydroxyl contents were used to improve the toughness of polycarbonate （PC） through reactive melt blending. A largely improved toughness of PC has been achieved, and the low temperature toughness of PC/PDMSOH blends could overtake that of PC homopolymer in much higher temperatures （e.g. -10 ~C versus 23 ~C）. Moreover, it was found that the more the hydroxyl content, the less the PDMSOH was needed to reach the highest toughness, suggesting that equivalent molar ratio between the carbonyl group content of PC and the hydroxyl group content of PDMSOH was required for the toughening of PC. Ultraviolet spectrophotometry was used to analyze the possible reaction between PC and PDMSOH. Contact angle was measured to assess the change of interfacial interaction between PC and PDMSOH as change of viscosity and hydroxyl content. The formation of PC-co-PDMSOH copolymer was believed to be the key for the toughening effect. This work gives a profound recommendation of the optimum kind and dosage of PDMSOH which should be used to improve the toughness of PC and will find immediate industrial applications.

关键词： Blends Low temperature toughness Polycarbonate Polydimethylsiloxane.

Preparation of Low Ratio Magnesium Ccement by Acid Leaching Treatment of Boron Mud

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 120-129页

作者： YANG mei zhang Mingzhe CHEN Hao School of Materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China School of Physical Science and Technology Shenyang Normal UniversityShenyang 110168China

The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of MgO/MgCl_(2),the amount of water added,and the amount of acid-impregnated slag dosed on the compressive strength and water resistance of *** results showed that the magnesium element in the boron mud could be maximally leached under the conditions of 1:1 concentration of hydrochloric acid at room temperature,liquid-solid ratio of 2.5 mL·g^(-1),and reaction time of 5 h,and the main products were amorphous SiO_(2) as well as a small amount of magnesium olivine which had not been completely *** LR-MOC prepared using the acid-soaked mixture could reach a softening coefficient of 0.85 for 28 d of water immersion when the molar ratio of MgO/MgCl_(2) was 2.2,the amount of water added was 0 g,and the acid-soaked slag dosing was 40 wt%,which also led to an appreciable late-strength,with an increase of 19.4%in compressive strength at 28 d compared to that at 7 *** previous studies,LR-MOC prepared in this way has a final strength phase that is not the more easily hydrolysed 3-phase but the lath-like *** this phenomenon,we analyzed the mechanism and found that,during the acid leaching process,a part of amorphous SiO_(2) dissolved in the acid leaching solution formed a silica sol,in which Mg^(2+)played a bridging role to make the silica sol more *** the addition and hydrolysis of MgO,the silica sol gel coagulation slows down,providing a capping layer to inhibit the hydrolysis of the 5-phase crystals and providing some strength after *** amorphous SiO_(2) in the other part of the acid-impregnated slag generated M-S-H gel with Mg^(2+)and OH-,which synergised with the dense structure composed of interlocking crystals to improve the water resistance of LR-MOC.

关键词： boron mud magnesium chloride-oxygen cement acid immersion water resistance silica sol

MixerKT:A Knowledge Tracing Model Based on Pure MLP Architecture

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Computers, Materials & Continua 2025年第1期82卷 485-498页

作者： Jun Wang Mingjie Wang Zijie Li Ken Chen Jiatian mei Shu zhang Key Laboratory of Education Informatization for Nationalities Ministry of EducationYunnan Normal UniversityKunming650000China Yunnan Key Laboratory of Smart Education Yunnan Normal UniversityKunming650000China

In the field of intelligent education,the integration of artificial intelligence,especially deep learning technologies,has garnered significant *** tracing(KT)plays a pivotal role in this field by predicting students’future performance through the analysis of historical interaction data,thereby assisting educators in evaluating knowledgemastery and tailoring instructional *** knowledge tracingmethods,largely based on Recurrent Neural Networks(RNNs)and Transformer models,primarily focus on capturing long-term interaction patterns in sequential ***,these models may neglect crucial short-term dynamics and other relevant *** paper introduces a novel approach to knowledge tracing by leveraging a pure Multilayer Perceptron(MLP)*** proposeMixerKT,a knowledge tracing model based on theHyperMixer framework,which uniquely integrates global and localMixer feature *** architecture enables more effective extraction of both long-terminteraction trends and recent learning behaviors,addressing limitations in currentmodels thatmay overlook these key *** evaluations on twowidely-used datasets,ASSIS Tments2009 and Algebra2005,demonstrate that MixerKT consistently outperforms several state-of-the-art models,including DKT,SAKT,and Separated Self-Attentive Neural Knowledge Tracing(SAINT).Specifically,MixerKT achieves higher prediction accuracy,highlighting its effectiveness in capturing the nuances of learners’knowledge *** results indicate that our model provides a more comprehensive representation of student learning patterns,enhancing the ability to predict future performance with greater precision.

关键词： Knowledge tracing multilayer perceptron channel mixer sequence mixer

Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： mei zhang Wenhao Li Yangfei Chen Yang Jiang Xiaofei Guo Han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

Modeling and control of a rigid-flexible coupling robot for narrow space manipulations

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Science China Technological Sciences 2025年

作者： Kuangda CHEN Huan ZHAO Jiexin zhang mei FENG Yiwei WANG Jinliang WANG Han DING State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and Technology Key Laboratory of CNC Equipment Reliability Ministry of Education Jilin University School of Medical Equipment Science and Engineering Huazhong University of Science and Technology

Narrow space manipulations are crucial for equipment maintenance, as they eliminate the need for disassembly, thus reducing costs and increasing efficiency. Cable-driven flexible robots possess exceptional capabilities in maneuvering through narrow spaces, thanks to their interaction compliance and distal dexterity. However, their inherent low stiffness causes a decline in the location accuracy of the robot and could even lead to manipulation failure. To address this challenge, this paper proposes a novel type of rigid-flexible coupling robot, which increases the stiffness of the robot while ensuring the reachability within a narrow space. To achieve high-accuracy location in a narrow space, kinematic and control methods are proposed. Specifically,the robot forward kinematics are uniformly represented, and the closed-form inverse kinematics solution is derived. Furthermore, in cases where the robot?s structure fails to align with Pieper?s solution, a two-stage search strategy is utilized to solve the inverse kinematics, resulting in a high success rate of 99.1%. Based on the proposed kinematics, a rigid-dominated control method is then proposed to facilitate localization and pose alignment of target objects in narrow spaces. The practical comparative experiments show that the proposed robot has the capability of high accuracy control in narrow spaces.

关键词：

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盐碱池塘浮游动物的种类组成和生物量

水产学报 2001年第1期25卷 26-31页

作者：赵文董双林张美昭张兆琪李德尚青岛海洋大学教育部水产养殖开放实验室!山东青岛266003

:1997年 4月 5日至 1998年 9月 1日对山东高青盐碱池塘浮游动物的种类组成和季节变动进行了研究。结果表明 ,高青盐碱池塘含盐量变动于 1.36～ 2 0g·L-1,总碱度变动于 2 .4～ 7.2mmol·L-1,pH值 8～ 9。浮游动物主要是淡水耐盐种或喜盐... 详细信息

:1997年 4月 5日至 1998年 9月 1日对山东高青盐碱池塘浮游动物的种类组成和季节变动进行了研究。结果表明 ,高青盐碱池塘含盐量变动于 1.36～ 2 0g·L-1,总碱度变动于 2 .4～ 7.2mmol·L-1,pH值 8～ 9。浮游动物主要是淡水耐盐种或喜盐种 ,一些是典型的盐水种。浮游动物优势种有团焰毛虫、双环栉毛虫、锥瓶口虫、瓜形膜袋虫、旋回侠盗虫和绿色前管虫 (原生动物 ) ;褶皱臂尾轮虫、暗小异尾轮虫、萼花臂尾轮虫、角突臂尾轮虫、壶状臂尾轮虫、卜氏晶囊轮虫、简单前翼轮虫、角三肢轮虫和针簇多肢轮虫 (轮虫 ) ;微型裸腹和长肢秀体(枝角类 ) ;细巧华哲水蚤、近邻剑水蚤和台湾温剑水蚤 (桡足类 )。无鱼对照池和新挖池塘的浮游动物生物量均较一般养鱼池塘的高

关键词：盐碱池塘浮游动物种类组成生物量山东省

变温对刺参幼参生长、呼吸代谢及生化组成的影响

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水产学报 2005年第5期29卷 77-83页

作者：董云伟董双林张美昭田相利王芳中国海洋大学海水养殖教育部重点实验室中国海洋大学海水养殖教育部重点实验室山东青岛266003

为研究刺参对温度周期性波动的响应,本实验测定了在12,15,18,21,24℃5个恒温处理组和15±2℃,18±2℃,21±2℃3个变温处理下刺参幼参的生长、呼吸代谢和生化组成。结果表明,在恒温条件下,随着温度的升高,刺参生长逐渐加快,在18℃生长最... 详细信息

为研究刺参对温度周期性波动的响应,本实验测定了在12,15,18,21,24℃5个恒温处理组和15±2℃,18±2℃,21±2℃3个变温处理下刺参幼参的生长、呼吸代谢和生化组成。结果表明,在恒温条件下,随着温度的升高,刺参生长逐渐加快,在18℃生长最快,然后随温度增加,生长逐渐降低。在15~21℃恒温条件下,幼参呼吸代谢无显著差异。在不同恒温处理组中,幼参脂肪含量随体重增加而增加。与恒温对照组相比,变温对幼参生长有显著性影响(P<0.05)。与相应的恒温相比,平均温度低于最适温度的变温(15±2℃,18±2℃)可促进刺参的生长,而平均温度高于最适温度时的变温(21±2℃)会抑制刺参生长。变温使幼参耗氧率有增加的趋势,但未达到显著水平。变温造成刺参脂肪含量降低,可能与变温条件下呼吸代谢增加有关。

关键词：刺参变温生长耗氧率生化组成

[Advances in molecular networking technology for discovering emerging contaminants and transformation products]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 33-42页

作者： Xiao-mei Tan Yu-Wei zhang Zhao-Yu Jiao Nan-Yang Yu Si Wei State Key Laboratory of Pollution Control & Resource Reuse School of Environment Nanjing University Nanjing 210046 China.

Emerging contaminants and their transformation products are widely distributed in the environment. These pollutants carry unknown risks owing to their persistence, migration, and toxicity. The wide variety and complex structures of these substances render them difficult to identify using only target analysis. Suspect screening analysis can identify more substances than target analysis in a single run. However, this analysis method is based on limited data and cannot meet the growing demand for compound identification, especially for emerging contaminants and their transformation products with unknown information. The development of high-resolution mass spectrometry technology has promoted the applications of nontarget analysis in the environmental field, especially for identifying unknown transformation products. At present, the challenges of nontarget analysis include the difficulty of finding compounds of interest and their transformation products from complex data. Molecular networking calculates the similarity between mass spectra based on an improved cosine similarity algorithm. This method can cluster molecular families with similar structures, achieve visualization and a collection of massive mass spectral datasets, and promote the annotation of pollutants through networks and communities. Molecular networking can globally organize and systematically interpret complex tandem mass spectral datasets, providing a new direction for nontarget analysis. This technology was first used in proteomics and gradually introduced into metabolomics for the discovery of new natural products. Recently, it has been introduced into the environmental field for the study of various man-made chemicals, particularly for the discovery of emerging contaminants and their transformation products. In this paper, we introduce a molecular networking analysis method based on high-resolution tandem mass spectrometry and describe its applications in the nontargeted screening of emerging cont

关键词： emerging contaminants high-resolution tandem mass spectrometry molecular networking transformation products

机体离子浓度对药物离子迁移率影响的模拟研究

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泰山医学院学报 2002年第2期23卷 116-118页

作者：酆建淑赵爽张玫张芹英仲伟纲泰山医学院放射系山东泰安271000

目的　研究机体离子浓度对药物离子迁移率的影响 ,为临床利用直流电离子透入疗法进行药物治疗提供实验依据。方法　采用模拟的方法 ,用稀盐酸 (HCI)中的氢离子 (H+ )代替药物离子 ,用稀盐水润湿了的滤纸代替机体 ,观察在电场力的作用下... 详细信息

目的　研究机体离子浓度对药物离子迁移率的影响 ,为临床利用直流电离子透入疗法进行药物治疗提供实验依据。方法　采用模拟的方法 ,用稀盐酸 (HCI)中的氢离子 (H+ )代替药物离子 ,用稀盐水润湿了的滤纸代替机体 ,观察在电场力的作用下H+ 从正极向负极移动的情况。结果　H+ 的迁移率随稀盐水的浓度增加而减小。结论　相同浓度的药物离子。

关键词：机体离子浓度药物离子迁移率影响模拟研究直流电离子透入疗法迁移速度

Icariin contributes to healing skull defects in rabbit models

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Journal of Traditional Chinese Medicine 2021年第3期41卷 470-477页

作者： HAO Fuliang mei shuang LIU Xiao LIU Yang zhang Xudog DONG Fusheng Department of Oral and maxillofacial surgery Hebei Key Laboratory of StomatologyHebei Clinical Research Center for Oral DiseasesSchool and Hospital of StomatologyHebei Medical UniversityShijiazhuang050017China

OBJECTIVE: To investigate the efficacy of icariin for healing skull defects in rabbit ***: Thirty-six 3-month-old female New Zealand white rabbits, weighing 1.8-2.0 kg each, were randomly divided into either the control or experimental group. Skull defect models were constructed in both groups, with the experimental group receiving oral icariin afterwards. At 4, 8 and 12 postoperative weeks, the rabbits were euthanized, and X-rays and samples were taken. Tissue sections were stained using hematoxylin and eosin, followed by additional processing using histological and bone metrological methods for observing the rate and quality of the bone ***: Histologically, additional mature lamellar bone formed in the defect area in the experimental group compared with that of the control *** metrological methods showed that the bone mass, trabecular bone width and number of osteoblasts in the experimental group were significantly higher than those of the control group(P 0.05).CONCLUSION: Icariin increased the bone mass and improved the condition of the defect area in the rabbit skulls.

关键词： osteogenesis icariin skull defect bone metrology