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Signatures of shear thinning-thickening transition in steady shear flows of dense non-Brownian yield stress systems

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Science China Chemistry 2015年第6期58卷 1013-1020页

作者： Wen Zheng Yu Shi ning Xu CAS Key Laboratory of Soft Matter Chemistry Hefei National Laboratory for Physical Sciences at the Microscale Department of Physics University of Science and Technology of China

Steady shear flows of dense athermal systems composed of soft disks are investigated via non-equilibrium molecular dynamics simulations, from which we sort out links among the structure, dynamics, and shear rheology. The systems at rest are jammed packings of frictionless disks with a nonzero yield stress. Driven by low shear rates, the flows shear thin due to the presence of the nonzero yield stress, but transit to shear thickening above a crossover shear rate γc - At γc, we observe the strongest struc- tural anisotropy in the pair distribution function, which serves as the structural signature of the shear thinning-thickening tran- sition. We also observe dynamical signatures associated with the transition： At γc , scaling behaviors of both the mean squared displacement and relaxation time undergo apparent changes. By performing a simple energy analysis, we reveal an underlying condition for the shear thickening to occur： d（lnTg）/d（Inγ）〉 2 with Tg the kinetic temperature. This condition is confirmed by simulations.

关键词： shear thickening shear thinning structural anisotropy dynamics kinetic temperature

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自定位卡扣的一体式发泡橡胶保护线束设计

机械工程师 2025年第1期 122-124页

作者：方宁郭剑峰浙江创格科技股份有限公司浙江诸暨311816

传统的车辆保护线束通常会采用胶带包扎保护或双层热缩管热缩保护,但车辆发动机内部长期处于高温重油污的环境,这些方法都不能很好地保护线束。文中介绍了一种新型的发动机保护线束,该种线束采用一体式发泡橡胶外壳保护线束,能够更好地... 详细信息

传统的车辆保护线束通常会采用胶带包扎保护或双层热缩管热缩保护,但车辆发动机内部长期处于高温重油污的环境,这些方法都不能很好地保护线束。文中介绍了一种新型的发动机保护线束,该种线束采用一体式发泡橡胶外壳保护线束,能够更好地保护发动机内部线束,隔绝油污和高温对线束的伤害,从而延长发动机内部线束的使用寿命,并且该种保护线束还设计了自定位卡扣,能够合理利用发动机内部空间,需要维修时也能更加快捷迅速地找到线束位置,提高效率。

关键词：车辆线束保护线束发泡橡胶自定位卡扣

Novel Newton’s learning algorithm of neural networks

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Journal of Systems Engineering and Electronics 2006年第2期17卷 450-454页

作者： Long ning Zhang Fengli Coll. of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P.R. China

Newton＇s learning algorithm of NN is presented and realized. In theory, the convergence rate of learning algorithm of NN based on Newton＇s method must be faster than BP＇s and other learning algorithms, because the gradient method is linearly convergent while Newton＇s method has second order convergence rate. The fast computing algorithm of Hesse matrix of the cost function of NN is proposed and it is the theory basis of the improvement of Newton＇s learning algorithm. Simulation results show that the convergence rate of Newton＇s learning algorithm is high and apparently faster than the traditional BP method＇s, and the robustness of Newton＇s learning algorithm is also better than BP method＇ s.

关键词： Newton's method Hesse matrix fast learning BP method neural network.

Energy principle and material removal sequence optimization method in machining of aircraft monolithic parts

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Chinese Journal of Aeronautics 2020年第10期33卷 2770-2781页

作者： Yinfei YANG Longxin FAN Liang LI Guolong ZHAO ning HAN Xiaoyue LI Hui TIAN ning HE College of Mechanical&Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China AVIC Xi’an Aircraft Industry(Group)Company LTD Xi’an 710089China

In the machining process of aircraft monolithic parts,the initial residual stress redistribution and structural stiffness evolution often lead to unexpected *** the other hand,the stress redistribution and stiffness reduction during the machining process depend on the material removal *** essence of the stress redistribution is releasing the initial elastic strain *** the present study,the influence of the material removal sequence on the energy release is ***,a novel optimization method is proposed for the material removal *** order to evaluate the performance of the proposed method,the mechanism of the machining distortion is firstly analyzed based on the energy *** a calculative model for the machining distortion of long beam parts is established ***,an energy parameter related to the bending distortion and the procedure of the material removal sequence optimization is ***,the bending distortion analysis and material removal sequence optimization are performed on a long beam with a Z-shaped ***,simulation and experiments are carried *** obtained results indicate that the optimized sequence results in a low distortion fluctuation and decreases the bending distortion.

关键词： Aircraft monolithic part Distortion Initial residual stress Material removal sequence Strain energy

Directly electrospinning submillimeter continuous fibers on tubes to fabricate H2S detectors with fast and high response

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Nano Materials Science 2022年第4期4卷 376-382页

作者： Xutao ning Dou Tang Ming Zhang Hunan Provincial Key Laboratory of Fine Ceramics and Powder Materials School of Materials and Environmental EngineeringHunan University of HumanitiesScience and TechnologyLoudiChina College of Resources&Environment Hunan Agricultural UniversityChangsha410128China School of Physics and Electronics Hunan UniversityChangsha410082China

The fast and high response detection of neurotoxic H_(2)S is of great importance for the *** this paper,directly electrospinning technology on the ceramic tube is developed to improve the response of H_(2)S detector based on superlong SnO_(2)*** submillimeter continuous fibers are deposited directly on ceramic tubes by in-situ electrospinning method and can keep morphology of fibers during *** employing this technology,CuO-doped SnO_(2)fiber H_(2)S detectors are fabricated,and 10%atom CuO-doped SnO_(2)H_(2)S detector shows the highest response of 40 toward 1 ppm H_(2)S at 150℃while the response is only 3.6 for the H_(2)S detector prepared in traditional *** addition,the in-situ electrospinning H_(2)S detectors show faster response and recovery compared to the H_(2)S detectors fabricated by the conventional *** high and fast response of H_(2)S detectors based on in-situ electrospinning can be ascribed to the continuous fiber structure and CuO *** present in-situ electrospinning technology may provide a new strategy for the development of other gasdetectors and bio-detectors with fast and high response.

关键词： Submillimeter continuous fibers H2S detectors In-situ fabrication

Oral administration of geranylgeranylacetone plus local somatothermal stimulation: A simple, effective, safe and operable preconditioning combination for conferring tolerance against ischemia-reperfusion injury in rat livers

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World Journal of Gastroenterology 2005年第36期11卷 5725-5731页

作者： ning Fan Guang-Shun Yang Jun-Hua Lu ning Yang Hai-Bin Zhang Department of Laparoscopy Affiliated Eastern Hospital of Hepatobiliary Surgery Second Military Medical University Shanghai 200438 China

AIM： To explore a simple, effective, safe and operable pretreatment for conferring tolerance against ischemia- reperfusion （I-R） injury in rat livers. METHODS： Forty-five rats were divided into five groups （each group n = 9）. Group C： control group; group G： geranylgeranylacetone （GGA） was administered without heat stress; group S： local heat stress alone; group WG： GGA plus whole-body heat stress; group SG： GGA administration plus local heat stress. After completion of the I-R procedure, the ischemic-reperfused liver lobes in five groups were resected and tested for heat shock protein （HSP70） by RT-PCR, Western blotting analysis and immunohistochemical staining. The blood samples were collected for ALT and AST measurement at the end of occlusion of blood supply, 30 min after reperfusion, 24, 48, 72 h after surgery from the inferior vena cava. Survival was monitored for 1 wk. RESULTS： The production of HSP70 after I-R injury increased, the liver enzyme levels after reperfusion decreased rapidly, and the survival rates increased in groups C-SG. CONCLUSION： The combination of GGA plus local somatothermal stimulation is a simple, effective, safe and operable pretreatment to induce HSP70 in patients with liver tumor and cirrhosis before hepatectomy and in donors before harvesting graft for liver transplantation.2005 The WJG Press and Elsevier Inc. All rights reserved.

关键词： Ischemia-reperfusion injury Heat shock protein Geranylgeranylacetone, Local somatothermal stimulation

METASTABLE　PHASE　AND　AGE　HARDEning　IN　RAPIDLY－SOLIDIFIED　SILVER－RICH　Ag－Gd　ALLOYS

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中国有色金属学会会刊：英文版 1996年第4期6卷 138-143页

作者： ning Yuantao(Institute of Precious Metals,Kunming 650221) Institute of Precious Metals Kunming 650221 China

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关键词： metastable phase age hardening rapidly-solidified Ag-Gd alloy

Investigation of Combining Plant Genotypic Values and Molecular Marker Information for Constructing Core Subsets

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Journal of Integrative Plant Biology 2006年第11期48卷 1371-1378页

作者： Jian-Cheng Wang Jin Hu ning-ning Liu Hai-Ming Xu Sheng Zhang Department of Agronomy Zhejiang University Hangzhou 310029 China

In the present study, a strategy was proposed for constructing plant core subsets by clusters based on the combination of continuous data for genotypic values and discrete data for molecular marker InformaUon. A mixed linear model approach was used to predict genotyplc values for eliminating the environment effect. The ＂mixed genetic distance＂ was designed to solve the difficult problem of combining continuous and discrete data to construct a core subset by cluster. Four commonly used genetic distances for continuous data （Euclidean distance, standardized Euclidean distance, city block distance, and Mahalanobls distance） were used to assess the validity of the conUnuous data part of the mixed genetic distance; three commonly used genetic distances for discrete data （cosine distance, correlaUon distance, and Jaccard distance） were used to assess the validity of the discrete data part of the mixed genetic distance, A rice germplasm group with eight quantitative traits and information for 60 molecular markers was used to evaluate the validity of the new strategy. The results suggest that the validity of both parts of the mixed geneUc distance are equal to or higher than the common geneUc distance. The core subset constructed on the basis of a combination of data for genotyplc values and molecular marker information was more representative than that constructed on the basis of data from genotypic values or molecular marker informaUon alone. Moreover, the strategy of using combined data was able to treat dominant marker informaUon and could combine any other continuous data and discrete data together to perform cluster to construct a plant core subset.

关键词： cluster core subset genotypic value mixed linear model molecular marker information

Impacts of the annual cycle of background SST in the tropical Pacific on the phase and amplitude of ENSO

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 12-17页

作者： Song Jiang Congwen Zhu ning Jiang State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina

The dominant annual cycle of sea surface temperature(SST)in the tropical Pacific exhibits an antisymmetric mode,which explains 83.4%total variance,and serves as a background of El Niño-Southern Oscillation(ENSO).However,there is no consensus yet on its anomalous impacts on the phase and amplitude of *** on data during 1982-2022,results show that anomalies of the antisymmetric mode can affect the evolution of ENSO on the interannual scale via Bjerknes feedback,in which the positive(negative)phase of the antisymmetric mode can strengthen El Niño(La Niña)in boreal winter via an earlier(delayed)seasonal cycle transition and larger(smaller)annual *** magnitude of the SST anomalies in the equatorial eastern Pacific can reach more than±0.3◦C,regulated by the changes in the antisymmetric mode based on random sensitivity *** reveal the spatial pattern of the annual cycle associated with the seasonal phase-locking of ENSO evolution and provide new insight into the impact of the annual cycle of background SST on ENSO,which possibly carries important implications for forecasting ENSO.

关键词： Annual cycle SST anomaly Antisymmetric mode ENSO