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Factors Influencing Dual Phase Steel Flanging Limit Punching

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Journal of Iron and Steel Research International 2014年第12期21卷 1124-1128页

作者： Jian-qing qian Yuan YUE Anhui University of Technology

Based on pre punching to hot rolled martensitic and bainitic dual phase steels with similar elongation and work hardening index （n）, as well as similar thickness and hole expansion test using taper die, analysis of the hole expansion rate indicated significant difference in their flanging performance. The results indicated that mechanical property was not the only major factor that influenced flanging. Further analysis of the hole border microstructure, work hardening condition, and fracture property showed that the fracture property of sheets was the major factor that influenced flanging performance.

关键词： flanging fracture property mechanical property dual phase steel

CHAOTIC TRANSIENTS IN A CURVED FLUID CONVEYING TUBE

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Acta Mechanica Solida Sinica 2005年第3期18卷 207-214页

作者： Ni Qiao Wang Lin qian qin Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China

The chaotic transients of a curved fluid conveying tube subjected to a nonlinear foundation are investigated. The assumption of the inextensibility of the tube is applied to derive the nonlinear differential equation of motion via the Newtonian approach, with the differential quadrature method used to discretize the curved tube model in the spatial domain. And the nonlinear dynamic motion equation is obtained. The numerical analysis shows that, the final steady states are sensitive to the initial system conditions in a large parameter region of the fluid speed. This phenomenon of chaotic transients is infrequent for fluid conveying tubes.

关键词： curved fluid conveying tube chaotic transient nonlinear dynamics DQM

Rh-Catalyzed Kinetic Resolution-Based Enantioselective[4+2]-Cydoaddition-lsomerization of Allene-1,3-dienes

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Chinese Journal of Chemistry 2021年第3期39卷 559-565页

作者： Anni qin qian Zhang Hui qian Yulin Han Shengming Ma Research Center for Molecular Recognition ond Synthesis Deportment of ChemistryFudan University220 Handan LuShanghai 200433China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling inShanghai 200032China

Main observation and conclusion The first example of Rh-catalyzed kinetic resolution of 1,3-disubstituted allene-1,3-dienes involving intramolecular[4+2]-cycloaddition has been *** by C=C isomerization,the reaction finally afforded aza-[4.3.0]bicyclic compounds with a very high en-antio-and *** mechanism has been unveiled by careful control *** synthetic potentials of highly enanti-oenriched bicyclic products have also been demonstrated.

关键词： Rhodium Cycloaddition Kinetic resolution Allenes Isomerization

Optimization of CO_2 separation technologies for Chinese refineries based on a fuzzy comprehensive evaluation model

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Petroleum Science 2015年第1期12卷 197-206页

作者： qian-qian Song qing-Zhe Jiang Zhao-Zheng Song State Key Laboratory of Heavy Oil Processing China University of Petroleum

This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristics of flue gas from Chinese refineries, three feasible CO2 separation technologies are selected. These are pressure swing adsorption （PSA）, chemical absorption （CA）, and membrane absorption （MA）. Secondly, an economic assessment of these three techniques is carried out in accordance with cash flow analysis. The results show that these three techniques all have economic feasibility and the PSA technique is the best. Finally, to further optimize the three techniques, a two-level fuzzy comprehensive evaluation model is established, including economic, technological, and environmental factors. Considering all the factors, PSA is optimal for Chinese refineries, followed by CA and MA. Therefore, to reduce Chinese refineries carbon emission, it is suggested that CO2 should be captured from off-gases using PSA.

关键词： Chinese refineries CO2 emission Separation technique Economic evaluation AHP-entropy method Fuzzy comprehensive evaluation model

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基于质性分析的网络社会排斥前因机制探究

心理技术与应用 2025年第1期13卷 35-43页

作者：秦萌萌孙倩邵爱国苏州科技大学教育学院苏州215009

运用扎根理论,借助NVivo软件对国内文献、网络热帖评论及深度访谈资料进行质性分析,探讨网络社会排斥的前因机制。结果发现,网络环境对互动对象社会排斥行为的归因倾向是影响网络社会排斥的关键因素,特别是形象意识高的个体,其拒绝敏感... 详细信息

运用扎根理论,借助NVivo软件对国内文献、网络热帖评论及深度访谈资料进行质性分析,探讨网络社会排斥的前因机制。结果发现,网络环境对互动对象社会排斥行为的归因倾向是影响网络社会排斥的关键因素,特别是形象意识高的个体,其拒绝敏感性强,更容易作出消极归因并陷入自我否定,消极情绪增加,从而加剧了网络社会排斥。而个体向往情绪的增多、高质量的现实人际关系及与互动对象紧密的现实关系距离则能减少对互动对象行为的消极归因,有助于缓解或预防网络社会排斥。此外,网络发展、网络特征及使用特征也在一定程度上催生了网络社会排斥。研究结果能为后续实证研究提供理论研究框架,为治理网络社会排斥问题提供有益参考。

关键词：网络社会排斥影响因素归因倾向质性分析

Squeezing Transformation of Three-Mode Entangled State

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Communications in Theoretical Physics 2005年第5X期44卷 911-916页

作者： qian Xiao-qing SONG Tong-qiang Department of Physics Ningbo University Ningbo 315211 China

We introduce the three-mode entangled state and set up an experiment to generate it. Then we discuss the three-mode squeezing operator squeezed ｜p, X2, X3〉→μ^-3/2｜p/μ, X2/μ, X3/μ） and the optical implement to realize such a squeezed state. We also reveal that c-number .asymmetric shrink transform in the three-mode entangled state, i.e. ｜p, X2,X3）→μ^-1/2｜p/μ, X2,X3）, maps onto a kind of one-sided three-mode squeezing operator {iλ （∑i^3=1 Pi）（∑i^3=1 Qi） -λ/2}. Using the technique of integration within an ordered product （IWOP） of operators, we derive their normally ordered forms and construct the corresponding squeezed states.

关键词： three-mode entangled state c-number asymmetric shrink transform one-sided three-mode squeezing operator

Contribution of citizen science towards cryptic species census： “many eyes” define wintering range of the Scaly-sided Merganser in China's Mainland

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Avian Research 2018年第1期9卷 63-72页

作者： qing Zeng qian Wei Guangchun Lei School of Nature Conservation Beijing Forestry University Beijing 100083 China China Birdwatching Association Chengdu 610041 China

Background: Citizen science has tremendous potential in advancing scientific knowledge and improving natural resource *** detect the wintering distribution of the endangered species Scaly-sided Merganser(Mergus squamatus), national wintering surveys were organized by China Birdwatching ***: The surveys of *** were conducted in three successive winters from 2014 to 2016.A total of 2019 people from 102 organizations participated in the *** three groups of 13 environmental variables, species distribution model for its wintering distribution of each year was developed using random ***'s D index was used to compare the distribution of *** in 3 ***: Totally, 441, 634 and 1138 individuals of *** were recorded in 2014, 2015 and 2016 *** main sites in Dabie Mountain and East qinling mountains were verified and the wintering range of *** was *** wintering range was found to be highly identical for the 3 ***: The highly overlapped distribution range among years suggested that the wintering range of *** was relatively *** organized and coordinated citizen science can be used to define distribution range and improve species conservation.

关键词： Wintering distribution Citizen science Mergus squamatus Random forest

Prenatal ultrasonographic findings in Klippel-Trenaunay syndrome:A case report

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World Journal of Clinical Cases 2021年第35期9卷 10994-10998页

作者： Hou-qing Pang qian-qian Gao Department of Ultrasound West China Second University HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Key Laboratory of Obstetric&Gynecological and Pediatric Diseases and Birth Defects of Ministry of Education Sichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Klippel-Trenaunay syndrome(KTS)is a rare congenital disorder.A detailed prenatal ultrasound examination plays an important role in the diagnosis of KTS and the subsequent counseling and follow-up of the *** SUMMARY A 25-year-old woman attended our department for a regular *** whole of the right lower extremity and right buttock were observed to be markedly thicker compared to the left one at 18 wk of ***,the lengths of the right femur,tibia and fibula were in the normal *** marked edema and fluid/cystic spaces were detected in the lower *** were no other organ *** vasculature in the right limb was visibly dilated,with much higher intensive blood flow *** congenital embryonic veins were visible in both *** right lower limb exhibited much more hypertrophy compared to the left limb two weeks *** and genetic tests showed normal results with 46 *** the normal karyotype,the family opted to terminate the *** post-mortem examination confirmed asymmetric hypertrophy of the right limb in the fetus and revealed a large area of marked dark-purple superficial capillary malformations occupying the skin of the right lower *** enlargement of veins and soft tissue hypertrophy were also seen on postnatal X-ray and Magnetic Resonance *** revealed severe congestion in the right lower limb.A final diagnosis of KTS was *** KTS may be diagnosed prenatally based on the typical features observed during ultrasound examination.

关键词： Klippel-Trenaunay syndrome Prenatal diagnosis Ultrasonography Case report

Modified likelihood ratio test for homogeneity in normal mixtures with two samples

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Applied Mathematics(A Journal of Chinese Universities) 2008年第1期23卷 113-119页

作者： qin Yong-song LEI qing-zhu School of Math. Sci. Guangxi Normal Univ. Guilin 541004 China.

This paper investigates the modified likelihood ratio test（LRT） for homogeneity in normal mixtures of two samples with mixing proportions unknown. It is proved that the limit distribution of the modified likelihood ... 详细信息

关键词： mixture model likelihood ratio test asymptotic distribution.