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Study on the Friction Coefficient in Grinding

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厦门大学学报（自然科学版） 2002年第S1期41卷 119-120页

作者： CAI Guang-qi 1. FENG Bao-fu 1. JIN Tan 2, GONG ya-dong 1.(1. School of Mechanical Engineering & Automation, Northeastern Unive rsity, Shenyang 1.0004, China 2. School of Industrial & Manufacturing Science, Cranfield University, Cranfield, Bedfordshire, UK)

The friction between the abrasive grains and workpi ec e is a crutial factor determining the main grinding output. Few studies have bee n carried out investigating the values of the friction coefficient in grinding, due to the difficulty of direct measurement. In this paper, a mathematical model of the friction coefficient in grinding has been established with the aid of a new grinding parameter C ge, which has close relations to wheel wear rate Z s, metal removal rate Z w, specific energy u and grinding force ratio λ(λ=F n/F t). By monitoring the process forces, C ge can be obtained and used easily for different grinding methods. Heavy grinding with different wheels and also single-grit grinding tests have been conducted for various work materials. The friction coefficients under different grinding conditions have been obtaine d using the model and the experimental results. For most materials tested in pap er, the friction coefficients decrease with the grinding speed. The friction coe fficients in single-grit grinding are 0.61.0.84 at the speed of 0.028 m/s, and 0.09～0.34 at the speed of 67～1.0 m/s. In single-grit grinding for 45 # a nd 20Cr steels, the friction coefficients decrease with the increase of the grindi ng speed while below a critical speed, and increase slightly with the increase o f grinding speed while above the critical grinding speed. Owing probably to the high surface temperature caused by high power consumption and dry condition, the friction coefficients in heavy grinding are 0.09～0.1., distinctly lower than t h ose of single-grit grinding, and also lower than those of ordinary grinding. Du e to the softening of the metals, the friction coefficients in heavy grinding un der dry condition are lower than that in wet condition. Owing probably to the di fference of hardness and roughness, while using different types of wheel and abr asive, the friction coefficients for the same work material changes even at same grinding speed. The work materials a

关键词： grinding friction coefficient model

DSC Analysis of LT-3 Aluminum Alloy Vacuum Brazing

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Journal of Shanghai Jiaotong university(Science) 2005年第2期10卷 182-185,189页

作者：冯涛吴鲁海楼松年李亚江 School of Materials Science and Eng. Shanghai Jiaotong Univ. Shanghai 200030 China School of Materials Science and Eng. Shandong Univ. Ji'nan 250061

LT-3 aluminum alloy is a kind of two-side cladding aluminum special used in vacuum brazing. Differential Scanning Calorimeter （DSC） was used to measure the exothermic and endothermic reaction during the brazing process that the cortex metal and the base metal are melted and re-crystal. The analysis results inidicate that eutectic reaction is the main reaction in the melted cortex metal crystallization process. But the main reaction in the melted base metal crystallization process is the reaction that α-A1.segregated out. According to the experimental details, the critical work of nucleation is 3.82×1.-1.J, the critical radius of nucleation is 8.69×1.-1. m, the volume of critical crystal nucleus is 2.75×1.-27 m3 and the per unit cell in critical crystal nucleus is 43.

关键词： aluminum alloy differential scanning calorimeter(DSC) analysis critical nucleation

东海、黄海发现的我国海洋微型硅藻的4个新记录种

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海洋学报 2003年第S2期25卷 140-144页

作者：李扬高亚辉厦门大学生命科学学院福建厦门361005

利用透射电镜对采自东海、黄海海域典型站位的微型硅藻的种类组成进行了研究,发现了我国首次记录的4种微型硅藻:大洋海链藻、英国舟形藻、李氏菱形藻和印度针杆藻.对这4个新记录种的分类特征、生态习性和分布做了详细的描述,并提供了相... 详细信息

利用透射电镜对采自东海、黄海海域典型站位的微型硅藻的种类组成进行了研究,发现了我国首次记录的4种微型硅藻:大洋海链藻、英国舟形藻、李氏菱形藻和印度针杆藻.对这4个新记录种的分类特征、生态习性和分布做了详细的描述,并提供了相应的壳面电镜照片.

关键词：微型硅藻新记录种东海、黄海海域

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集中化调车作业研究

铁道学报 2004年第6期26卷 8-13页

作者：高四维高雅西南交通大学峨眉校区交通运输系四川峨眉614202 西南交通大学计算机与通信工程学院四川成都610031

在分析自动化指挥系统与作业组织方式相互关系的基础上,以提高整体调车效率为目标,提出集中运用调车设备、进行整批次高深度选编、使多元性选编目标综合达成的集中化调车作业新模式;在研究集中化调车作业与分散化调车作业取向差异的基础... 详细信息

在分析自动化指挥系统与作业组织方式相互关系的基础上,以提高整体调车效率为目标,提出集中运用调车设备、进行整批次高深度选编、使多元性选编目标综合达成的集中化调车作业新模式;在研究集中化调车作业与分散化调车作业取向差异的基础上,明确了集中化调车作业的采用条件,指出盲目分散化作业的主要表现;论证集中化选编模型的有效性及推行集中化调车作业的必要性;在实现自动化指挥的条件下,就如何采用集中化作业组织方式提出了具体建议。

关键词：调车作业优化集中化选编模型集中化作业组织方式自动化指挥系统

Fuzzy-grey Prediction of Cutting Force Uncertainty in Turning

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Fuzzy-grey Prediction of Cutting Force Uncertainty in Turnin...

第十届国际制造工程与管理会议

作者： WANG Wei-ping, PENG Yong-hong, LI Xi-ya (1. Department of Mechanical Engineering, Dongguan University of Technology, Dongguan 5231.6, China 2. Department of Computer Science, University of Bristol, UK)

To predict the extent of turning force uncertainty quantitatively, this paper proposes a fuzzy-grey prediction procedure based on the symmetric fuzzy number and linear planning theory and grey set theory. To verify the developed procedure, a measuring system of turning force is schematized to acquire the evaluating data. The comparison between the prediction results and measured data demonstrates that the prediction is an extent of variable force rather than a certain point for the given turning conditions, and the measured force drops into the extent with smaller relative error. In addition, the procedure only needs less experimental data in modeling. This work is new and original, and helpful for engineering application.

关键词： uncertainty fuzzy-grey prediction turning force

来源： cnki会议评论

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不规则波浪数值水槽的造波和阻尼消波

海洋学报 2002年第2期24卷 127-132页

作者：高学平曾广冬张亚天津大学建筑工程学院天津300072

利用MAC（marker and cell）法直接数值求解连续方程和N-S方程.为模拟不规则波长时段连续造波及消除波浪遇结构物后形成的二次反射,采用了源造波法.对开敞边界,采用了海绵阻尼消波和Sommerfeld条件相结合的处理方式.

关键词： MAC法不规则波浪数值水槽源造波法阻尼消波结构物

云南省临沧市小管福寿螺COⅠ基因多态性分析

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中国血吸虫病防治杂志 2018年第2期30卷 179-183页

作者：张苍林彭佳冉甄字金荣杨亚明云南省寄生虫病防治所普洱665099 昆明医科大学公共卫生学院

目的通过对云南省临沧市小管福寿螺(Pomacea canaliculata)COⅠ基因的遗传标记分析,了解当地小管福寿螺基因多态性,为云南省后续开展广州管圆线虫病监测提供科学依据。方法对采自云南省临沧市孟定镇38份小管福寿螺样本进行COⅠ基因扩增... 详细信息

目的通过对云南省临沧市小管福寿螺(Pomacea canaliculata)COⅠ基因的遗传标记分析,了解当地小管福寿螺基因多态性,为云南省后续开展广州管圆线虫病监测提供科学依据。方法对采自云南省临沧市孟定镇38份小管福寿螺样本进行COⅠ基因扩增,并将PCR产物测序。运用MEGA 6.06软件Kimura-2参数模型,对来自于Gen Bank的福寿螺单倍型与本研究获得单倍型一起进行系统进化树构建和个体间遗传距离计算,分析其遗传多样性。结果共获得31.序列,分属3种单倍型(Haplotype1.Haplotype3),其中Haplotype1.频率较高,占整个样本的83.9%(26/31.。3种单倍型与小管福寿螺的遗传距离最小,为0~0.052;而与Pila conica的遗传距离最大,为0.021.0.239。进一步进化分析表明,3种单倍型均为小管福寿螺,与来自日本熊本(Gen Bank登录号:AB 433769)、中国香港(Gen Bank登录号:KT 31.034)和美国夏威夷(Gen Bank登录号:EU 5231.9)的小管福寿螺序列聚成一大支,具有较近的亲缘关系;而与***(Gen Bank登录号:EF 51.942)、***(Gen Bank登录号:EF 51.059)等序列的亲缘关系较远。结论云南省临沧市存在小管福寿螺,本研究获得的3种单倍型之间存在较大的遗传分化。

关键词：小管福寿螺 COⅠ基因序列分析遗传多样性临沧市

Non-dimensional analysis on blast wave propagation in foam concrete:Minimum thickness to avoid stress enhancement

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Defence Technology（防务技术） 2024年第6期36卷 30-46页

作者： ya yang Xiangzhen Kong Qin Fang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007JiangsuChina

Foam concrete is a prospective material in defense engineering to protect structures due to its high energy absorption capability resulted from the long plateau ***,stress enhancement rather than stress mitigation may happen when foam concrete is used as sacrificial claddings placed in the path of an incoming blast *** investigate this interesting phenomenon,a one-dimensional difference model for blast wave propagation in foam concrete is firstly proposed and numerically solved by improving the second-order Godunov *** difference model and numerical algorithm are validated against experimental results including both the stress mitigation and the stress *** difference model is then used to numerically analyze the blast wave propagation and deformation of material in which the effects of blast loads,stress-strain relation and length of foam concrete are *** particular,the concept of minimum thickness of foam concrete to avoid stress enhancement is ***,non-dimensional analysis on the minimum thickness is conducted and an empirical formula is proposed by curve-fitting the numerical data,which can provide a reference for the application of foam concrete in defense engineering.

关键词： Foam concrete Blast wave propagation Non-dimensional analysis Stress enhancement

High-temperature wetting behavior between slag and refractory

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Journal of Iron and Steel Research International 2024年第6期31卷 1304-1319页

作者： Yong-xin Wang ya-ge Li ya-bo Gao Zhong Huang Hai-jun Zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Slag corrosion is one of the main factors of the damage of refractory,and its primary manifestations involve the melting of refractory in slag and the slag penetration into refractory,both of which are highly related to the wetting behavior between slag and *** high-temperature wettability could be characterized by parameters including the surface tension,adhesion work,and spreading coefficient of the slag on refractory surface,and it could be suppressed by altering the slag/refractory interface,thus resulting in an improved anti-corrosion *** this,the key knowledges of the slag corrosion,theory of wetting behavior and test of high-temperature contact angle were firstly ***,the major factors influencing the high-temperature slag wetting behavior were discussed based on the aspects of slag composition,refractory composition,and surface ***,the future research direction was proposed in this field.

关键词： High-temperature wetting Refractory Slag corrosion Surface tension