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基于等温面法的发动机活塞裙预锻模优化设计

锻压技术 2024年第2期49卷 220-226页

作者：史凯迪陈荣创张运军陶鹏张春湖北汽车工业学院材料科学与工程学院湖北十堰442002 湖北隆中实验室湖北襄阳441000 湖北三环锻造有限公司湖北襄阳441700 东风汽车股份有限公司湖北襄阳441000

为了改善预锻模开发设计周期长、成本高、依赖经验的问题,根据材料流动与热量传输的相似性原则,提出采用等温面法对预锻模进行优化设计。以柴油机活塞裙锻件为例,介绍了基于等温面法的预锻模设计过程,并选取了3、5、8和10℃的等温面进... 详细信息

为了改善预锻模开发设计周期长、成本高、依赖经验的问题,根据材料流动与热量传输的相似性原则,提出采用等温面法对预锻模进行优化设计。以柴油机活塞裙锻件为例,介绍了基于等温面法的预锻模设计过程,并选取了3、5、8和10℃的等温面进行模具设计和有限元分析。首先在ANSYS WORKBENCH软件温度场分析的基础上获得等温面,然后在Geomagic Studio软件中对等温面点云进行拟合,并在UG软件中设计出预锻模具,最后采用DEFORM软件模拟获得型腔填充率、最大锻造压力、等效应变分布和流线形状等,评估不同预锻模具方案的优缺点。结果表明:以8℃等温面为基础设计预锻模具,生产的锻件填充率高、最大锻造压力小,且磁粉探伤未发现开裂缺陷,锻件表面质量良好,满足生产要求。

关键词：等温面法活塞裙预锻模填充率锻造压力

Topological origin of global attractors in gene regulatory networks

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Science China(Physics,Mechanics & Astronomy) 2015年第2期58卷 101-108页

作者： zhang yunjun OUYANG Qi GENG Zhi Faculty of Foundation Education Peking University Health Science Center Center for Theoretical Biology School of Physics Peking University School of Mathematical Sciences Peking University

Fixed-point attractors with global stability manifest themselves in a number of gene regulatory networks. This property indicates the stability of regulatory networks against small state perturbations and is closely related to other complex dynamics. In this paper, we aim to reveal the core modules in regulatory networks that determine their global attractors and the relationship between these core modules and other motifs. This work has been done via three steps. Firstly, inspired by the signal transmission in the regulation process, we extract the model of chain-like network from regulation networks. We propose a module of "ideal transmission chain(ITC)", which is proved sufficient and necessary(under certain condition) to form a global fixed-point in the context of chain-like network. Secondly, by examining two well-studied regulatory networks(i.e., the cell-cycle regulatory networks of Budding yeast and Fission yeast), we identify the ideal modules in true regulation networks and demonstrate that the modules have a superior contribution to network stability(quantified by the relative size of the biggest attraction basin). Thirdly, in these two regulation networks, we find that the double negative feedback loops, which are the key motifs of forming bistability in regulation, are connected to these core modules with high network stability. These results have shed new light on the connection between the topological feature and the dynamic property of regulatory networks.

关键词： Boolean model bistability network module robustness

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中国典型砖形黑茶非挥发物的代谢组学分析

食品科学 2024年第18期45卷 160-167页

作者：余士兰张宁闫昊艺张运军韩晓玉任鸿宇凌铁军安茂强安徽农业大学茶树生物学与资源利用国家重点实验室安徽合肥230036 湖南省益阳茶厂有限公司湖南益阳413000

为探究我国典型砖形黑茶代谢物轮廓的规律,以及砖形黑茶与黑茶真菌在代谢物种类方面的关系,本研究利用基于液相色谱-质谱联用的非靶向代谢组学和基于特征物信息的质谱分子网络技术,对我国典型的砖形黑茶(湖北青砖茶、四川康砖茶、湖南... 详细信息

为探究我国典型砖形黑茶代谢物轮廓的规律,以及砖形黑茶与黑茶真菌在代谢物种类方面的关系,本研究利用基于液相色谱-质谱联用的非靶向代谢组学和基于特征物信息的质谱分子网络技术,对我国典型的砖形黑茶(湖北青砖茶、四川康砖茶、湖南的黑砖茶、花砖茶和茯砖茶、陕西的茯砖茶)以及茶鲜叶和分离自黑茶的多种真菌进行代谢组学分析。结果表明,砖形黑茶的非挥发性代谢物轮廓更倾向于按照生产地区进行分类,一组是来自湖南和陕西的砖形黑茶,而另一组是来自四川和湖北的砖形黑茶;决定其代谢物轮廓分组的最主要因素是砖茶含梗率,来自四川和湖北的砖形黑茶含梗率明显高于另一组;造成两组砖形黑茶轮廓差异的主要原因是湖南和陕西的砖形黑茶中有更高含量的黄烷-3-醇类和大部分氨基酸及其衍生物等代谢物;针对砖形黑茶和真菌代谢物的分子网络分析发现,在砖形黑茶中,尤其是在康砖茶中广泛分布着源自真菌的线性和环状二肽;在茯砖茶中有着结构种类丰富的异戊烯基二酮哌嗪类化合物,这类化合物来自于冠突散囊菌,因此,真菌为砖形黑茶贡献了种类丰富的代谢物。本实验结果可为全面了解和认识我国典型砖形黑茶的化学物质基础提供理论参考。

关键词：中国典型砖形黑茶代谢组学非挥发性代谢产物含梗率真菌质谱分子网络

Effect of component substitution on the microstructure and mechanical properties of MCoCrFeNiTi_x (M = Cu, Al) solid-solution alloys

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Rare Metals 2008年第6期27卷 627-631页

作者： ZHOU yunjun zhang Yong WANG Xuefei WANG Yanli CHEN Guoliang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

MCoCrFeNiTix （M = Cu, Al; x： molar ratio, x = 0, 0.5） alloys were prepared using the new alloy-design strategy of equal-atomic ratio and high entropy. By the component substitution orAl for Cu, the microstructure changes from the face-centered cubic solid solution of original CuCoCrFeNiTix alloys to the body-centered cubic solid solution of AlCoCrFeNiTix alloys. Compared with original CuCoCrFeNiTix alloys, AlCoCrFeNiTix alloys keep the similar good ductility and simultaneously possess a much higher compressive strength, which are even superior to most of the reported high-strength alloys like bulk metallic glasses.

关键词： solid-solution alloys microstructure mechanical properties component substitution high entropy

Study of third-order nonlinear susceptibility of polySchiff base containing triphenylamine

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Science China Chemistry 2007年第2期50卷 230-237页

作者： NIU HaiJun WANG Wen HUANG YuDong zhang YunDong zhang yunjun BAI XuDuo LIU Yuan Key Laboratory of Color and Macromolecular Chemistry Heilongjiang UniversityHarbin 150080China Institute of Advanced Ceramic Harbin Institute of TechnologyHarbin 150001China Department of Applied Chemistry Harbin Institute of TechnologyHarbin 150001China Institute of Opto-electronics Harbin Institute TechnologyHarbin 150001China

PolySchiff base containing triphenylamine has been synthesized by polycondensation and characterized by FT-IR, NMR, UV-visible spectrometer. Measurements of the third-order optical nonlinear susceptibility χ (3) by Z-scan technique have shown that the large nonlinearity is dominated by the two-photon absorption in PSB. The sign and size of real part Reχ (3), nonlinear refractive index n 2 have been measured with the condition of 532 nm, 8 ns-duration pulses to be ?1.23×10?10 esu, ?3.06×10?12 esu; nonlinear absorption index β and size of image part lmχ (3) to be 3.63×10?10 m/W, 1.15×10?11 esu, respectively, so the third-order nonlinear susceptibility χ (3) is 1.19×10?11 esu. The value is larger than other polymers reported. PSB is self-focusing material and has potential application in nonlinear optic field.

关键词： polySchiff base triphenylamine third-order susceptibility Z-scan

Plasma‐oxidized 2D MXenes subnanochannel membrane for high‐performance osmotic energy conversion

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Carbon Energy 2024年第8期6卷 178-191页

作者： Zhengmao Ding Tiancheng Gu Rui zhang Shouyi Sun Kaiqiang Wang Hanli zhang Jinjin Li yunjun Luo State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijingChina Key Laboratory of High Energy Density Materials Ministry of EducationBeijing Institute of TechnologyBeijingChina Department of Engineering Mechanics Northwestern Polytechnical University(Chang'an Campus)Xi'anChina

Nanofluidic channels inspired by electric eels open a new era of efficient harvesting of clean blue osmotic energy from salinity *** by less charge and weak ion selectivity of the raw material itself,energy conversion through nanofluidic channels is still facing considerable ***,a facile and efficient strategy to enhance osmotic energy harvesting based on drastically increasing surface charge density of MXenes subnanochannels via oxygen plasma is *** plasma could break Ti–C bonds in the MXenes subnanochannels and effectively facilitate the formation of more Ti–O,C═O,O–OH,and rutile with a stronger negative charge and work function,which leads the surface potential of MXenes membrane to increase from 205 to 430 *** significant rise of surface charge endows the MXenes membrane with high cation selectivity,which could make the output power density of the MXenes membrane increase by 248.2%,reaching a high value of 5.92Wm^(−2)in the artificial sea‐river water ***,with the assistance of low‐quality heat at 50℃,the osmotic power is enhanced to an ultrahigh value of 9.68Wm^(−2),which outperforms those of the state‐of‐the‐art two‐dimensional(2D)nanochannel *** exciting breakthrough demonstrates the enormous potential of the facile plasma‐treated 2D membranes for osmotic energy harvesting.

关键词： ion transport MXenes membranes osmotic energy harvesting plasma two‐dimensional nanochannels

Significance of vulnerability assessment in establishment of Hainan provincal disaster medical system

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亚太热带医药杂志：英文版 2011年第8期4卷 594-596页

作者： Min Li Chuanzhu Lu Wei Son Junhong Miao Yipeng Ding Longhe Li Leilei zhang Nin Zhao Bijiang Hu yunjun zhang Hainan People's Hospital Hainan Medical College Hainan Normal University

Hainan is an island province in south China with a high frequency of unconventional emergencies due to its special geographic location and national military defense *** the limited transportation route from Hainan to the outside world,self-rescue is more important to Hainan Province than other provinces in China and it is therefore imperative to establish an independent, scientific as well as efficient provincal disaster medical system in *** regulatory role for vulnerability analysis/assessment has been demonstrated in establisment of disaster medical system in varoius countries and or *** this paper,we attempt to describe/propose how to adopt vulnerability assessment through mathematical modeling of major biophysical social vulnerability factors to establish an independent,scientific,effieicnt and comprehensive provincial disaster medical system in Hainan.

关键词： Vunlerability analysis Disasters medical Emergency medical rescue

144型高性能转向节预锻件优化设计与精锻工艺研究

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模具工业 2024年第3期50卷 59-62页

作者：余国林夏巨谌孔德瑜张运军陈天赋邓磊冯仪余俊夏自力湖北三环锻造有限公司湖北襄阳441700 华中科技大学材料成形与模具技术全国重点实验室湖北武汉430074 武汉新威奇科技有限公司湖北鄂州436070

144型转向节是中重型高端商用车转向部件中的核心零件,其对延伸率和断面收缩率均有严格要求,根据传统锻造工艺理论设计的预锻方案不能满足断面收缩率要求,研究其预锻件的优化设计与精锻终成形工艺对于获得合格锻件具有重要意义。首先采... 详细信息

144型转向节是中重型高端商用车转向部件中的核心零件,其对延伸率和断面收缩率均有严格要求,根据传统锻造工艺理论设计的预锻方案不能满足断面收缩率要求,研究其预锻件的优化设计与精锻终成形工艺对于获得合格锻件具有重要意义。首先采用经典塑性成形理论分析了基于传统方法设计的预锻件存在的问题,然后基于损伤理论提出了其预锻件结构的优化设计方法,同时提出了基于平面薄飞边的精锻终成形工艺。应用结果表明,生产的144型转向节精密锻件阶梯杆部的关键技术指标延伸率A≥12.5%,断面收缩率Z≥50%,超过了国外客户所提技术指标的要求。

关键词： 144型高性能转向节预锻件优化精锻终成形平面薄飞边断面收缩率

CO2 assisted steam flooding in late steam flooding in heavy oil reservoirs

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Petroleum Exploration and Development 2019年第6期46卷 1242-1250页

作者： XI Changfeng QI Zongyao zhang yunjun LIU Tong SHEN Dehuang MU Hetaer DONG Hong LI Xiuluan JIANG Youwei WANG Hongzhuang State Key Laboratory of Enhanced Oil Recovery PetroChina Research Institute of Exploration&DevelopmentBeijing 100083China Research Institute of Petroleum Exploration&Development PetroChinaBeijing 100083China Research Institute of Petroleum Exploration&Development PetroChina Xinjiang Oilfield CompanyKaramary 834000China

To improve the oil recovery and economic efficiency in heavy oil reservoirs in late steam flooding,taking J6 Block of Xinjiang Oilfield as the research object,3D physical modeling experiments of steam flooding,CO2-foam assisted steam flooding,and CO2 assisted steam flooding under different perforation conditions are conducted,and CO2-assisted steam flooding is proposed for reservoirs in the late stage of steam *** experimental results show that after adjusting the perforation in late steam flooding,the CO2 assisted steam flooding formed a lateral expansion of the steam chamber in the middle and lower parts of the injection well and a development mode for the production of overriding gravity oil drainage in the top chamber of the production well;high temperature water,oil,and CO2 formed stable low-viscosity quasi-single-phase emulsified fluid;and CO2 acted as a thermal insulation in the steam chamber at the top,reduced the steam partial pressure inside the steam chamber,and effectively improved the heat efficiency of injected *** on the three-dimensional physical experiments and the developed situation of the J6 block in Xinjiang Oilfield,the CO2 assisted steam flooding for the J6 block was *** application showed that the CO2 assisted steam flooding made the oil vapor ratio increase from 0.12 to 0.16 by 34.0%,the oil recovery increase from 16.1%to 21.5%,and the final oil recovery goes up to 66.5%compared to steam flooding after perforation adjustment.

关键词： heavy oil reservoir three-dimensional physical simulation experiment steam flooding CO2 assisted steam flooding steam chamber steam(CO2)chamber overriding gravity drainage