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Unveiling the dynamic instability mechanism of microstructure transformation in faceted oxide eutectic composite ceramics

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Journal of Materials Science & Technology 2023年第13期144卷 224-234页

作者： Haijun Su Yuan Liu Qun Ren Zhonglin Shen min Guo Xi Li jun Zhang Lin Liu Hengzhi Fu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China Department of Material Science and Engineering Shanghai UniversityShanghai 200072China

Microstructure control is a great challenge in the high-temperature gradient directional solidification of eutectic composite ceramics due to the complex solidification ***,the microstructure trans-formation of faceted Al_(2)O_(3)/Er_(3)Al_(5)O_(12) thermal emission eutectic composite ceramics is explored over wide ranges of compositions(13.5 mol%-22.5 mol%Er_(2)O_(3))and solidification rates(2-200μm/s).Entirely cou-pled eutectics with primary phases suppressed are fabricated and the coupled zone is broadened in a wide range of 15.5 mol%-22.5 mol%Er_(2)O_(3) at low solidification *** competitive growth between eutectic and dendrite is evaluated on the basis of the maximum interface temperature *** ad-dition,the mechanisms of irregular eutectic spacing selection and adjustment under different solidifi-cation rates are revealed based on Magnin-Kurz model.A successful prediction of lamellar to rod-like eutectics is achieved associated with the dynamic instability of lamellar eutectic and the corresponding enlarged coexistence region is mapped based on the interface *** to the well mi-crostructure tailoring,the flexural strength of Al_(2)O_(3)/Er_(3)Al_(5)O_(12) eutectic composite ceramics has improved from 508 MPa up to 1800 MPa due to the refined eutectic spacing with low *** eutectic composite ceramics show strong selective optical absorption and the intensity increases with the refin-ing *** as-designed Al_(2)O_(3)/Er_(3)Al_(5)O_(12) composites with microstructural tailoring have great potential as integrations of structural and functional materials.

关键词： Directional solidification Laser floating zone melting Al_(2)O_(3)/Er_(3)Al_(5)O_(12)eutectic composite ceramics Eutectic growth mechanism Microstructure transformation

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基于脉冲神经网络的时空交互图像分类

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计算机系统应用 2024年第5期33卷 162-169页

作者：曲海成李竹媛刘万军辽宁工程技术大学软件学院葫芦岛125105

脉冲神经网络作为人工智能发展的重要方向之一,在神经形态工程和类脑计算领域得到了广泛的关注.为解决脉冲神经网络泛化性差、内存和时间消耗较大等问题,本文提出了一种基于脉冲神经网络的时空交互图像分类方法.首先引入时间有效训练算... 详细信息

脉冲神经网络作为人工智能发展的重要方向之一,在神经形态工程和类脑计算领域得到了广泛的关注.为解决脉冲神经网络泛化性差、内存和时间消耗较大等问题,本文提出了一种基于脉冲神经网络的时空交互图像分类方法.首先引入时间有效训练算法弥补梯度下降过程中的动能损失;其次融合空间随时间学习算法,提高网络对信息的高效处理能力;最后添加空间注意力机制,增强网络对空间维度上重要特征的捕捉能力.实验结果表明,改进后的方法在CIFAR10、DVS Gesture、CIFAR10-DVS这3个数据集上的训练内存占用分别减少了46.68%、48.52%、10.46%,训练速度分别提升了2.80倍、1.31倍、2.76倍,在保证精度的情况下,网络性能得到有效提升.

关键词：脉冲神经网络时间有效训练空间随时间学习空间注意力机制人工智能

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SYNTHESIS OF POLYURETHANE MODIFIED BISMALEIMIDE (UBMI) AND POLYURETHANE-IMIDE ELASTOMER

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Chinese Journal of Polymer Science 2008年第1期26卷 117-119页

作者： Xu, Tao Yuan, Wei Wang, Shen-jun Li, Zai-feng Sun, Bao-quan Wang, min-xuan Qingdao Univ Sci & Technol Coll Chem & Mol Engn Qingdao 266042 Peoples R China SINOPEC Shengli Petr Adm Inst Oil Proc Shengli Oilfield Dongying 257001 Peoples R China

Urethane modified bismaleimide(UBMI)was synthesized by the reaction of maleic anhydride(MA)with NCO group terminated polyurethane prepolymer(PUP)in presence of *** product was determined by infrared analysis. Then ultrasonic assistant process was introduced into the solvent removal of the prepolymer mixture of UBMI and PUP. Polyurethane-imide(PUI)elastomer was synthesized from the above PUP-UBMI prepolymer mixture by the infusion technology with 2,5-dimethyl-2,5-bis(tert-butylperoxy)-hexane(B25)as l...

关键词： UBMI Polyurethane-imide Preparation

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Concurrent Upward Lightning Flashes from Two Towers

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Atmospheric and Oceanic Science Letters 2014年第3期7卷 260-264页

作者： JIANG Ru-Bin SUN zhu-Ling WU Zhi-jun Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology

Upward lightning flashes initiated simultane- ously from two towers separated by a distance of 3420 m were analyzed in detail based on high-speed camera images and S-band Doppler radar echo intensity. Both discharges lasted more than 250 ms and were self-initiated from the towers in the form of upward positive leaders with a time difference of less than 4 ms. Abundant recoil leaders oc- curred transiently in the remnant channel sections during the development of the upward lightning. The number of recoil leaders over the lower tower was greater than over the higher tower. When the concurrent upward flashes occurred, the radar echo intensity in the area of the towers was no more than 45 dBZ and the towers were separately located beneath two echo centers with low altitudes of 2-3 kin.

关键词： towerupward lightningleaderdischarge

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Effect of the catalyzing combustion of coke breeze on the energy saving in sinter process

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Journal of Central South University of Technology 2001年第4期8卷 234-238页

作者： zhu De qing,QIU Guan zhou,JIANG Tao,zhu Bao jun (Department of mineral Engineering, Central South University, Changsha 410083, China) Department of mineral Engineering Central South University Changsha China

The mechanism of additive ZC 1 for catalyzing combustion of coke breeze in sintering of iron ore fines was studied by using X ray Diffraction, TGA and GC(Gas Chromatographer), by which energy saving was achieved on sinter pot test. The results show that the distance between cleavage planes is enlarged and the π electrons are re distributed because of the insertion of cations/molecules of ZC 1 into the cleavage planes of carbon , resulting in the weakening of C-C bond, improving the adsorption of oxygen and lowering the activation energy of gasification of carbon from 25.8 kJ/mol to 18.9 kJ/mol , and the burning rate being increased and combustion residual reduced, all of which can lead to lower solid fuel consumption . Compared with the sintering test without addition of additives , the solid fuel consumption is reduced by 16.0%, meanwhile, the rate of finished sinter, the output of finished sinter and the tumbling index are increased by 2.03%, 7.0% and 3.71% , respectively, with incorporating 0.2% of additive ZC 1 in the sintering mixture, which is in agreement with the catalyzing mechanism of ZC 1.

关键词： sintering coke breeze additive catalyzing combustion energy saving

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Dynamic-static coupled sensing of trace biomarkers by molecularly imprinted metal-organic frameworks

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Science China Chemistry 2023年第12期66卷 3511-3517页

作者： Hui min Zongsu Han Tiankai Sun Kunyu Wang jun Xu Peiyu Yao Sihai Yang Peng Cheng Wei Shi Department of Chemistry Key Laboratory of Advanced Energy Materials Chemistry(MOE)and Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China School of Materials Science and Engineering&National Institute for Advanced Materials Center for Rare Earth and Inorganic Functional Materials Tianjin Key Lab for Rare Earth Materials and ApplicationsNankai UniversityTianjin 300350China Department of Emergency Tianjin Union Medical CenterTianjin 300121China Department of Chemistry University of ManchesterManchester M139PLUK College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Accommodating target analytes within the pores of metal-organic frameworks(MOFs)to improve the sensing performance is an important but challenging ***,we report a novel molecular imprinting strategy to create target recognition sites in a tailored multicomponent MOF with the inter-ligand synergistic antenna effect to lanthanide ions,enabling selective recognition of trace biomarkers,which is critical to the early diagnosis of age-related diseases in blood samples with high sensitivity and ultralow limit of detection(LOD)of 69 nmol L^(-1).Compared with MOF-based sensors without imprinted recognition sites,the significantly enhanced sensing performance(both sensitivity and LOD)was attributed to a dynamic-static coupled sensing mechanism:the dynamic interactions involve concentrating the trace biomarkers at the imprinted recognition sites to enhance the sensing performance at ultralow concentration,and the static interactions are derived from electron/energy exchange between the molecularly imprinted MOF and the biomarker to govern the sensing *** work establishes a new molecular imprinting strategy to attain advanced materials for sensing trace bio-analytes.

关键词： molecularly imprinted metal-organic frameworks dynamic-static coupled sensing biomarker recognition

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Evaluation on Effectiveness and Safety of Chinese Herbs inTreatment of Sub-health: A Systematic Review andMeta-Analysis of Randomized Controlled Trials

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Chinese Journal of Integrative Medicine 2019年第6期25卷 471-480页

作者： ZHAO jun LIAO Xing ZHAO Hui LI Zhi-geng WANG Nan-yue WANG Li-min China Academy of Chinese Medical Science Beijing (100700) China Beijing University of Chinese Medicine Beijing (100029) China Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical Science Beijing (100700) China Institute of Basic Theory for Chinese Medicine China Academy of Chinese Medical Sciences Beijing (100700) China Experimental Research Center China Academy of Chinese Medical Sciences Beijing (100700) China

Objective: To evaluate the effectiveness and safety of Chinese herbs in the treatment of sub-health systematical y. Methods: Nine databases were systematicaly and extensively searched to col ect randomized control ed trials(RCTs) about Chinese herbs in the treatment of sub-health. The outcomes included overal effective rate, main symptoms, quality of life, etc. Literature screening, data extraction and quality assessment were conducted according to Cochrane Handbook 5.1. Meta-analysis was conducted to the included literature with Review Manager ***: Seventy-two studies involving 9,296 patients with sub-health were included with 4,908 patients in experimental groups and 4,387 patients in control groups. The overal quality of included clinical research was not high. In the aspect of improving overall effective rate, relieving main symptoms, Pittsburgh sleep quality index(PSQI) score, Athens Insomnia Scale(AIS) score, Fatigue Scale-14(FS-14), Cornel Medical Index(CMI) score and discontinuation rate, the effects of experimental groups were better than that of control groups. According to available research reports, adverse reactions in Chinese herb groups were mainly mild gastrointestinal symptoms, which did not affect the ***: Chinese herbs have a curative effect in the treatment of sub-health. However, there are no clear criteria for diagnosis and curative effectiveness judgment global y, which would affect the accuracy of curative effect evaluation.

关键词： sub-health randomized controlled trials Chinese medicine systematic review

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Various configuration types of the foveal avascular zone with related factors in normal Chinese adults with or without myopia assessed by swept-source OCT angiography

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International Journal of Ophthalmology(English edition) 2022年第9期15卷 1502-1510页

作者： Yan-min Dong Hai-Yan zhu Zhen-Hui Liu Shu-Ying Fu Ke Wang Li-Ping Du Xue-min Jin Department of Ophthalmology the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina

·AIM:To describe the morphological characteristics of foveal avascular zone(FAZ)in normal Chinese adults with or without myopia by swept-source optical coherence tomography angiography(SS-OCTA)and analyze the possible associated factors.·METHODS:Normal Chinese adults with or without myopia aged between 18 and 60 y were recruited into the *** eye in each individual was randomly selected for scanning using *** parameters,central retinal thickness(CRT)and central choroidal thickness(CCT)were then *** between systemic and ocular variables and FAZ parameters were subsequently *** subgroup analysis based on refractive error was also carried out.·RESULTS:In total,127 eyes out of 127 normal subjects were finally included in the study(mean age29.5±8.22 y,61 males and 66 females).The pattern of FAZ was variable:round configuration in 28 eyes(22%),quadrilateral configuration in 23 eyes(18%),pentagonal configuration in 20 eyes(16%),oval configuration in 15 eyes(12%),triangular configuration in 6 eyes(5%)and irregular configuration in 35 eyes(28%).The mean area of FAZ was0.37±0.12 mm^(2).Females had a larger FAZ(0.41±0.11 mm^(2)vs0.32±0.11 mm^(2))compared with that of males(P<0.01).All myopic individuals showed smaller FAZ area and perimeter compared with that of normal individuals(P<0.01).There was no obvious correlation between age and *** the univariate regression analysis,both axial length(AL)and refractive error were significantly related to FAZ ***,only CRT showed negative correlation with FAZ in the multivariate regression analysis.·CONCLUSION:The pattern of FAZ configuration in normal Chinese adults with or without myopia is highly *** quantitative parameters of FAZ would not only provide details of macular pathophysiology but could possibly contribute as a biomarker in disease staging.

关键词： foveal avascular zone swept-source optical coherence tomography angiography central retinal thickness myopia

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Correlation between Helicobacter pylori-associated gastric diseases and colorectal neoplasia

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World Journal of Gastroenterology 2016年第18期22卷 4576-4584页

作者： Ying Qing min Wang Ying-min Lin Dong Wu Jing-Yu zhu Lang Gao Yan-Yan Liu Teng-Fei Yin Department of Geriatric Gastroenterology Qi-Lu Hospital of Shandong University Department of General Medicine Qi-Lu Hospital of Shandong University Department of General Surgery Qi-Lu Hospital of Shandong University Department of Gastroenterology Jinan Central Hospital

AIM: To explore the correlation between Helicobacter pylori(H. pylori)-associated gastric diseases and colorectal ***: Patients included in this study underwent a colonoscopy and esophago-gastro-duodenoscopy(EGD) along with histopathological measurement between March 2012 and March 2015 at Qi-Lu Hospital of Shandong University, who also had results of H. pylori detection. A total of 233 cases were selected. Demographic data, H. pylori infection status(including results of rapid urease tests and gastric mucosa pathological examinations) and histopathological examination results of gastric and colorectal mucosa were gathered and analyzed. The statistical analysis focused on the prevalence of colorectal neoplasms among patients with various histopathological categories of the stomach. ORs and their 95%CI were calculated to describe the strengths of the ***: The incidence rates of colorectal adenoma without high-grade intraepithelial neoplasia(HGIEN)(OR = 2.400, 95%CI: 0.969-5.941), adenoma with HGIEN(5.333, 1.025-27.758) and adenocarcinoma(1.455, 0.382-5.543) were all higher for patients with H. pylori-associated gastritis than for those in the control group. The incidence rate of colorectal adenoma with HGIEN(3.218, 0.767-13.509) was higher in patients with intestinal metaplasia than in the control group, while the incidence rates of adenoma without HGIEN(0.874, 0.414-1.845) and adenocarcinoma(0.376, 0.096-1.470) were lower in the intestinal metaplasia group than in the control group. The incidence rate of colorectal adenoma without HGIEN(3.111, 1.248-7.753) was significantly higher in the gastric intraepithelial neoplasia group than in the control group, while the rates of adenoma with HGIEN(1.481, 0.138-15.941) and adenocarcinoma(2.020, 0.561-7.272) were higher in the gastric intraepithelial neoplasia group. Incidence rates of colorectal adenoma without HGIEN(1.067, 0.264-4.314), adenoma with HGIEN(2.667, 0.231-30.800) and adenocarcino

关键词： Helicobacter pylori Helicobacter pylori-associated gastric diseases Colorectal neoplasia Endoscopy with pathological biopsy Chinese population

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Constrained multiobjective robust optimization of a bistable mechanism for inertial switch

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Science China(Technological Sciences) 2023年第11期66卷 3186-3196页

作者： LIU min WANG WeiDong zhu Yingmin YUAN YangBo NIU YanXu DONG LinXi WANG ChenYing JIANG Kyle CHEN Guimin School of Mechano-Electronic Engineering Xidian UniversityXi’an 710071China School of Electronic Information Hangzhou Dianzi UniversityHangzhou 310018China Collaborative Innovation Center of High-End Manufacturing Equipment Xi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering University of BirminghamBirmingham B152TTUK School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China

This paper proposes an optimization method for finding the optimal design of a bistable mechanism with a desired performance that is robust to structural and material *** interval numbers to characterize the uncertainties in the structural parameters and materials,we present a nonprobabilistic multiobjective optimization model and transform it into a single objective optimization model using a penalty *** sensitivity of the mechanical performance of bistable structures to uncertain parameters was analyzed,and the design parameters with notable effects on the bistable performance were identified as optimization variables.A neural network-based proxy model for the nonlinear characteristics of the bistable mechanism was established,and its accuracy was validated through finite element *** on this model,a two-layer nested genetic algorithm was employed to solve the multiobjective robust optimization problem of the bistable structures with critical forces and a second stable *** effectiveness of the optimization method was verified by comparing it with the finite element and experimental *** proposed method was applied in the design of silicon-based inertial switches.

关键词： multiobjective robust optimization uncertainty interval analysis bistable mechanism

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