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Research on influence of mandril on cross section distortion in bending process of thin-walled rectangular wave-guide tube

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Research on influence of mandril on cross section distortion...

第五届国际材料与热加工物理模拟及数值模拟学术会议

作者： Y.L.Liu1 a G.Y.Zhao1 b C.h.Lu1 b and h.Yang1 c 1College of Materials Science and Engineering Northwestern Polytechnical University P.O.box 542 Xi’an Shaanxi 710072 P.R. China

The cross section distortion is a main forming defect occurred easily in the bending process of thin-walled rectangular wave-guide tube, consequently results in a poor forming precision and quality. but properly using a mandril is an effective resolution for this problem. So this paper mainly focuses on the role of a mandril in the bending process of thin-walled rectangular wave-guide tube to restrict the cross section distortion by numerical simulation. Firstly, a 3D-FEM model of rotary-draw bending process of aluminum alloy 3A21 thin-walled rectangular tube is developed under the environment of AbAQUS/Explicit, and its reliability is validated by experimental results. Then the influence laws of the mandril and its extension length on cross section distortion have been explored. The achievements of this study have a great significance and reference value for improving forming precision of bending process of thin-walled rectangular wave-guide tube.

关键词： Mandril Thin-walled rectangular wave-guide tube bending process Cross section distortion FEM analysis

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浸酸过程的研究

中国皮革 1976年第9期 36-44页

作者： h.赫尔费尔德 b.舒伯特蒲敏功

最近我们报道了关于动物皮在酸溶液中膨胀和肿胀性的研究,这个题目与其它较老研究的区别是除皮的膨胀外,也将肿胀性(就是说,纤维在三度空间的纤维编织中相互张开了)用数字测出,数值的测定不是间接经过膨胀伴随的水吸收进行的,而是直接... 详细信息

最近我们报道了关于动物皮在酸溶液中膨胀和肿胀性的研究,这个题目与其它较老研究的区别是除皮的膨胀外,也将肿胀性(就是说,纤维在三度空间的纤维编织中相互张开了)用数字测出,数值的测定不是间接经过膨胀伴随的水吸收进行的,而是直接取得的,即膨胀是经过皮厚度的测定,肿胀是经过可压缩性降低的测定。我们曾在这个

关键词：浸酸蚁酸食盐皮重抗衡离子重计甲酸氯化钠当量浓度裸皮

Garment embedded sweat-activated batteries in wearable electronics for continuous sweat monitoring

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npj Flexible Electronics 2022年第1期6卷 107-114页

作者： Xingcan huang Yiming Liu Jingkun Zhou Sina Khazaee Nejad Tsz hung Wong Ya huang hu Li Chun Ki Yiu Wooyoung park Jian Li Jingyou Su Ling Zhao Kuanming Yao Mengge Wu Zhan Gao Dengfeng Li Jiyu Li Rui Shi Xinge Yu Department of biomedical Engineering City University of Hong KongHong Kong 999077China hong Kong Center for Cerebra-Cardiovascular health Engineering Hong Kong Science ParkNew TerritoriesHong KongChina

Thin,soft,and skin-integrated electronic system has great advantages for realizing continuous human healthcare ***,we report an ultra-thin,flexible,and garment-based microelectronics powered by sweat-activated batteries(SAbs)and applications of powering biosensors and microelectronic systems for real time sweat *** SAb cell is ultra-thin(1.25 mm)with excellent *** SAb has good electricity output with high capacity(14.33 mAh)and maximum power density(3.17 mW cm^(−2))after being activated by the sweat volume of 0.045 mL cm^(−2),which could continuously power 120 light emitting diodes over 3 *** outputs could maintain stable after repeatable *** microelectronics system could be continuously powered by the SAbs for 3 h to monitor sweat and physiological information,including sweat Na+concentration,ph,and skin *** reported integrated system provides a potential for solving the power issues of flexible wearable electronics and realizing personalized medicine.

关键词： continuously system maintain

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泡沫与凝胶堵剂处理性能比较

石油石化节能与计量 1997年第6期 4-8+10页

作者： h．b．Nimir,R．S．Seright,唐孝芬北京石油勘探开发研究院

在这篇文章中，我们研究了在作为封诸剂时，泡沫是否能显示出比凝胶更优越的处理性能。尤其考察了极限毛细管压力的概念是否可以在高渗透层中形成稳定的、低流度泡沫，同时在低渗透层中能防止泡沫的产生及伤害。使用C14～16磺化α－烯... 详细信息

在这篇文章中，我们研究了在作为封诸剂时，泡沫是否能显示出比凝胶更优越的处理性能。尤其考察了极限毛细管压力的概念是否可以在高渗透层中形成稳定的、低流度泡沫，同时在低渗透层中能防止泡沫的产生及伤害。使用C14～16磺化α－烯烃，测量了一种氮气泡沫在渗透率为7.5～900mD范围岩芯中的流度(回压750lb／ln2，104°F），使用的泡沫量为50％～95％，渗流速率0．5～100ft/d。我们广泛地研究了泡沫处理后，注盐水驱替时的残余阻力系数，实验研究结果表明泡沫比凝胶具有更优越的处理性能。该研究还发现：和像水一样交联体系比较，当渗透率在7.5mD以下的低渗透层和80mD以上的高渗透层中，泡沫显示出比较好的处理性能。

关键词：封堵剂泡沫凝胶渗透率实验室试验

A STUDY ON ALUMINIDE COATINGS ON TiAl ALLOYS bY PACKCEMENTATION METhOD

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Acta Metallurgica Sinica(English Letters) 2000年第6期13卷 1148-1154页

作者： C.G. Zhou, h.b. Xu and S.K. Gong (Department of Materials Science and Engineering, beijing University of Aeronautics and Astronautics,beijing 100083, China) K. Y. Kim (Department of Materials Science and Engineering, Pohang University of Science and Techn

The halide-activated pack cementation method is utilized to deposit aluminide coat- ings on TiAl alloys. Emphasis is placed on the effect of alloying elements on the aluminizing behavior of TiAl alloy. The addition of a small amount of Nb or Cr in the TiAl improves significantly the aluminizing kinetics of TiAl alloys by increasing the solid-state division of Al through the formation of stable TiAl3 layer. The TiAl3 layer formed on the TiAl alloyed with Nb or Cr has better toughness than the TiAl3 formed on the non-alloyed TiAl. The reason for better toughness of the coating formed on TiAl is that partial TiAl3 with tetragonal structure was changed to high symmetry cubic L12 structure since Nb or Cr was dissolved into TiAl3. The TiAl3 layer formed on the TiAl alloyed with Nb or Cr has much better oxidation resistance than the TiAl3 layer formed on the non-alloyed TiAl. It is attributed to change in the crystal structure of TiAl3 from the brittle tetragonal DO22 to the ductile cubic L12 by addition of small amount of Nb or Cr.

关键词： TiAl alloying element pack cementation aluminizing

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泡沫与凝胶堵剂处理性能比较

国外油田工程 1997年第6期13卷 4-8,10页

作者： h.b.Nimir R.S.Seright 唐孝芬北京石油勘探开发研究院

关键词：封堵剂泡沫凝胶渗透率油田注水

NON-ISOMORPhIC GROUPS WITh ISOMORPhICSPECTRAL TAbLES AND bURNSIDE MATRICES

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Chinese Annals of Mathematics,Series b 1994年第3期15卷 273-282页

作者： W. KIMMERLE K. W. ROGGENKAMP(Mathematisches institut b, University of Stuttgalt, Pfthenwaldring 57, 70550 Stuttgart, Germany.) University of Stuttgart 德国

It was shown by Formanek and Sibley that the group determined characterizes a finite groupG up to isomorphism. hoehnke and Johnson (independelltly the suthors--using an argumentof Manslield) showed the corresponding result for k-characters, k = 1, 2, 3. The notion of kcharacters dates back to nobenius. They are determined by the group doterminaDt and maybe derived from the character table CT(G) provided one knows additionally the functionswhere C(C) = {Cg, g E G} denotes the set of conjugacy classes of *** object of the paper is to present criteria for finite groups (more precisely for solublegroups G and h which are both semi-direct products of a similar type) when1. G and h have isomorphic spectral tables (i.e., they form a brauer pair),2. G and h have isomorphic table of marks (in particular the burnside rings are isomorphic),3. G and h have the same *** this the authors construct two *** soluble groups for which all these threerepresent at iont heor et ical invar taut s coincide.

关键词： Finite group Spectral table burnside matriX Isomorphism.

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大陆地壳结构的气枪震源探测及其应用

中国科学：地球科学 2017年第10期47卷 1153-1165页

作者：陈颙王宝善姚华建南京大学地球科学与工程学院南京210046 中国地震局地震预测研究所北京100036 中国地震局地球物理研究所中国地震局地震观测与地球物理成像重点实验室北京100081 中国科学技术大学地球和空间科学学院地震与地球内部物理实验室合肥230026 中国科学技术大学蒙城地球物理国家野外科学观测研究站亳州233527

利用人工震源主动向地下发射地震波可以实现地下结构的高精度探测.合适的震源是进行主动源探测的关键.为研究大陆地壳结构及其变化,我们从爆破、电火花、落锤、偏心振动源、重载列车行驶产生的震动、变频汽车震源(Vibroseis)、水体中气... 详细信息

利用人工震源主动向地下发射地震波可以实现地下结构的高精度探测.合适的震源是进行主动源探测的关键.为研究大陆地壳结构及其变化,我们从爆破、电火花、落锤、偏心振动源、重载列车行驶产生的震动、变频汽车震源(Vibroseis)、水体中气体激发等多种震源中,遴选出水体中气体激发的人工震源(以下简称气枪)作为研究大陆地壳结构的震源.这种气枪震源具有绿色、环保、安全、高效等优点,是进行大陆地壳结构探测的新型人工震源.近年来,利用气枪震源分别在云南宾川、新疆呼图壁和甘肃张掖建成了3个固定式地震信号发射台,并开展了连续数年的监测.我们发现了气枪震源产生地震波信号高度重复的特点,利用这种特点,新疆人工水体中激发的地震波,在5000次叠加之后信号则可以追踪到近1300km,可探测面积为600万km^2,深达60km的地下结构.如果把这种人工主动震源看成是一盏照亮地下结构的明灯的话,在中国大陆,建立10个激发地震波的发射台,可以对中国大陆960万km^2的国土进行长时间连续的全覆盖探查,实现"天上有北斗,地下有明灯".

关键词：大陆地壳结构气枪震源绿色环保地下明灯

Effect of <i>Ginkgo biloba</i>Extract Ingestion on Plasma Total Cortisol Levels during an Oral Glucose Tolerance Test in Normal Glucose Tolerant Individuals

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Food and Nutrition Sciences 2014年第16期5卷 1561-1567页

作者： George b. Kudolo Department of Clinical Laboratory Sciences University of Texas Health Science Center San Antonio USA

Protracted periods of increased cortisol production, as may be seen in an acute illness, may lead to transient hyperglycemia. Increasing evidence suggests that cortisol may then mediate the development of insulin resistance and potentially lead to the development of overt diabetes. Evidence in animal studies also suggests that under conditions of stress Ginkgo biloba extract could reduce plasma cortisol production and so the primary aim of this study was to determine the effect of Ginkgo biloba extract ingestion on plasma cortisol production during an acute period of glucose challenge. healthy non-diabetic, glucose tolerant volunteers (n = 30, (10/20, M/F);age, 45.7 ± 9.9 years old) completed a randomized, double-blind, placebo-controlled crossover study when they ingested Ginkgo biloba extract (120 mg/day as a single dose) and placebo during each 3-month arm. A standard 75 g oral glucose tolerance test was performed at the end of each cycle and blood was collected and used to measure plasma glucose, insulin, c-peptide and cortisol. Fasting plasma cortisol was significantly lower after the Ginkgo biloba cycle than the placebo cycle (326 ± 149 vs. 268 ± 121 nmol/L, respectively;p = 019). The plasma cortisol area under the curve during the 2-hour test (AUC0-2) was also significantly lower after ingestion of the Ginkgo biloba cycle compared to the placebo (668 ± 265 vs. 530 ± 213 nmol/L/h, respectively;p hat the ingestion of Ginkgo biloba extract has effect on the hypothalamic-pituitary-adrenal axis leading to reduced basal cortisol levels and reduced cortisol production in response to acute hyperglycemic challenge.

关键词： Ginkgo biloba Extract Cortisol Acute hyperglycemia