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Simulative technology for auxiliary fuel tank separation in a wind tunnel

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Chinese Journal of Aeronautics 2016年第3期29卷 608-616页

作者： Ma Xin Liu Wei chen Ling Li Xiao Jia Zhenyuan shang Zhiliang Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education Dalian University of Technology

In this paper, we propose a simulative experimental system in wind tunnel conditions lbr the separation of auxiliary fuel tanks from an aircraft. The experimental system consists of a simulative release mechanism, a scaled model and a pose measuring system. A new release mechanism was designed to ensure stability of the separation. Scaled models of the auxiliary fuel tank were designed and their moment of inertia was adjusted by installing counterweights inside the model. Pose param- eters of the scaled model were measured and calculated by a binocular vision system. Additionally, in order to achieve high brightness and high signal-to-noise ratio of the images in the dark enclosed wind tunnel, a new high-speed image acquisition method based on miniature self-emitting units was pre- sented. Accuracy of the pose measurement system and repeatability of the separation mechanism were verified in the laboratory. Results show that the position precision of the pose measurement system can reach 0.1 mm, the precision of the pitch and yaw angles is less than 0.1° and that of the roll angle can be up to 0.3°. Besides, repeatability errors of models＂ velocity and angular velocity controlled by the release mechanism remain small, satisfying the measurement requirements. Finally, experiments for the separation of auxiliary fuel tanks were conducted in the laboratory.

关键词： Aircraft auxiliary equipmentBinocular vision Position and attitude mea-surement Release mechanism Simulation experiment

regeneration of thermally deactivated commercial V-W-Ti catalysts

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Frontiers of Chemical Science and Engineering 2012年第1期6卷 38-46页

作者： Xuesong shang Jianrong LI Xiaowei YU Jinsheng chen Chi HE Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Chemical Engineering Huaqiao UniversityXiamen 361021China

An effective method for the regeneration of thermally deactivated commercial monolith SCR catalysts was investigated. Two types of regenerated solutions, namely NH4C1 （l mol/L） and dilute H2SO4 （0.5 tool/L）, were employed to treat the used catalyst. The effects of temperature and the regeneration process on the structural and textural properties of the catalysts were determined by X-ray diffraction, scanning electron microscopy, N2 adsorption/desorption, elemental analysis and Fourier transform infrared spectroscopy. The results suggest that the anatase phase of the used catalyst is maintained after exposure to high temperatures. Some of the catalytic activity was restored after regeneration. The catalyst regenerated by aqueous NH4C1 had a higher activity than that of the catalyst treated by dilute H2SO4. The main reason is that the NH3 generated from the decomposition of NH4C1 at high temperatures can be adsorbed onto the catalyst which promotes the reaction. The aggregated V205 were partially re-dispersed during the regeneration process, and the intrinsic oxidation of ammonia with high concentrations of O2 is a factorthat suppresses the catalytic activity.

关键词： V2O5-WO3/TiO2 catalysts thermal deactiva-tion regeneration NH4C1 dilute H2SO4 solution

Modal structure and propagation of internal tides in the northeastern South China Sea

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Acta Oceanologica Sinica 2019年第9期38卷 12-23页

作者： Qian Liu Xiaohui Xie Xiaodong shang Guiying chen Hong Wang School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography Ministry of Natural Resources Hangzhou 310012 China State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

The evolution of energy, energy flux and modal structure of the internal tides (ITs) in the northeastern South China Sea is examined using the measurements at two moorings along a cross-slope section from the deep continental slope to the shallow continental shelf. The energy of both diurnal and semidiurnal ITs clearly shows a ~14-day spring-neap cycle, but their phases lag that of barotropic tides, indicating that ITs are not generated on the continental slope. Observations of internal tidal energy flux suggest that they may be generated at the Luzon Strait and propagate west-northwest to the continental slope in the northwestern SCS. Because the continental slope is critical-supercritical with respect to diurnal ITs, about 4.6 kJ/m^2 of the incident energy and 8.7 kW/m of energy flux of diurnal ITs are reduced from the continental slope to the continental shelf. In contrast, the semidiurnal internal tides enter the shelf because of the sub-critical topography with respect to semidiurnal ITs. From the continental slope to the shelf, the vertical structure of diurnal ITs shows significant variation, with dominant Mode 1 on the deep slope and dominant higher modes on the shelf. On the contrary, the vertical structure of the semidiurnal ITs is stable, with dominant Mode 1.

关键词： South China Sea internal tides propagation scattering modal structure

A Novel, Efficient and Facile Method for the Template Removal from Mesoporous Materials

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Chemical Research in Chinese Universities 2014年第6期30卷 894-899页

作者： chen Lu JIANG shang WANG Runwei ZHANG Zongtao QIU Shilun State Key Laboratory of Inorganic Synthesis & Preparative Chemistry Jilin University Changehun 130012 P. R. China College of Chemistry and Biology Beihua University Jilin 132013 P. R. China

A new catalytic-oxidation method was adopted to remove the templates from SBA-1 5 and MCM-4 1 me- soporous materials via Fenton-like techniques under microwave irradiation. The mesoporous silica materials were treated with different Fenton agents based on the template＇s property and textural property. The samples were cha- racterized by powder X-ray diffraction（XRD） measurement, N2 adsorption-desorption isotherms, infrared spectro- scopy, 29Si MAS NMR and thermo gravimetric analysis（TGA）. The results reveal that this is an efficient and facile approach to the thorough template-removal from mesoporous silica materials, as well as to offering products with more stable structures, higher BET surface areas, larger pore volumes and larger quantity of silanol groups.

关键词： Detemplation Mesoporous silica material Fenton technique Microwave Hydrogen peroxide

Application of Isogeometric Analysis Method in Three-Dimensional Gear Contact Analysis

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 817-846页

作者： Long chen Yan Yu Yanpeng shang Zhonghou Wang Jing Zhang School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai200093China Zhejiang Fine-Motion Robot Joint Technology Co. Ltd.Taizhou317600China

Gears are pivotal in mechanical drives,and gear contact analysis is a typically difficult problem to *** isogeometric analysis(IGA)methods have developed new ideas to solve this *** this paper,a threedimensional body parametric gear model of IGA is established,and a theoretical formula is derived to realize single-tooth contact *** were benchmarked against those obtained from commercial software utilizing the finite element analysis(FEA)method to validate the accuracy of our *** findings indicate that the IGA-based contact algorithmsuccessfullymet theHertz contact *** juxtaposed with the FEA approach,the IGAmethod demonstrated fewer node degrees of freedomand reduced computational units,all whilemaintaining comparable ***,the IGA method appeared to exhibit consistency in analysis accuracy irrespective of computational unit density,and also significantlymitigated non-physical oscillations in contact stress across the tooth *** underscores the prowess of IGA in contact *** conclusion,IGA emerges as a potent tool for addressing contact analysis challenges and holds significant promise for 3D gear modeling,simulation,and optimization of various mechanical components.

关键词： Contact analysis involute gear isogeometric analysis finite element analysis

Lightweight authentication scheme for edge control systems in Industrial Internet of Things

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FRONTIERS OF INFORMATION TECHNOLOGY & ELECTRONIC ENGINEERING 2024年第11期25卷 1466-1478页

作者： shang, Wenli Wen, Xudong chen, Zhuo Xiong, Wenze Chang, Zhiwei Cao, Zhong Guangzhou Univ Sch Elect & Commun Engn Guangzhou 510006 Peoples R China Instrumentat Technol & Econ Inst Beijing 100055 Peoples R China

In edge control systems (ECSs), edge computing demands more local data processing power, while traditional industrial programmable logic controllers (PLCs) cannot meet this demand. Thus, edge intelligent controllers (EICs) have been developed, making their secure and reliable operation crucial. However, as EICs communicate sensitive information with resource-limited terminal devices (TDs), a low-cost, efficient authentication solution is urgently needed since it is challenging to implement traditional asymmetric cryptography on TDs. In this paper, we design a lightweight authentication scheme for ECSs using low-computational-cost hash functions and exclusive OR (XOR) operations;this scheme can achieve bidirectional anonymous authentication and key agreement between the EIC and TDs to protect the privacy of the devices. Through security analysis, we demonstrate that the authentication scheme can provide the necessary security features and resist major known attacks. Performance analysis and comparisons indicate that the proposed authentication scheme is effective and feasible for deployment in ECSs.

关键词： Edge intelligent controller (EIC) Edge control systems (ECSs) Terminal devices (TDs) Anonymous authentication Lightweight authentication TP309

Construction of quaternary carbon centers by KOtBu-catalyzed α-homoallylic alkylation of lactams with 1,3-dienes

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Organic Chemistry Frontiers 2022年第6期9卷 1642-1648页

作者： shang Wang Yunfei Xiang Tiantian chen Xiang Wu Dong Xing shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China

We report a KOtBu-catalyzed α-homoallylic alkylation of lactams with 1,3-dienes. With this transitionmetal-free and atom-economical protocol, a variety of α-homoallylic alkylated lactams bearingα-quaternary carbon centers were formed in a 2,1-addition manner with excellent regioselectivity. Acation–π interaction between the in situ-generated potassium enolate and the diene is proposed to play akey role in accelerating this transformation.

关键词： quaternary centers catalyzed

Deformation behavior and microstructural evolution during hot compression of an a+b Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 344-351页

作者： Gao-feng Liu shang-zhou Zhang Li-qing chen Jian-xun Qiu School of Environmental and Materials Engineering Yantai University Yantai 264005 China State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

The effect of processing parameters on the flow response and microstructural evolution of the a＋b titanium alloy Ti-6.5Al-3.5Mo-1.5Zr-0.3Si has been studied by conducting isothermal hot compressive tests at a strain rate of 0.01-10 s-1 at 860-1100°C. The true stress-true strain curves of the sample hot-compressed in the a＋b phase region exhibit a peak stress followed by continuous flow softening, whereas in the b region, the flow stress attains a steady-state regime. At a strain rate of 10 s-1, the alloy exhibits plastic flow insta-bilities. According to the kinetic rate equation, the apparent activation energies are estimated to be about 674-705 kJ/mol in the a＋b region and 308-335 kJ/mol in the b region, respectively. When deformed in the a＋b region, the globularization process of the a colony structure occurs, and a dynamic recrystallized microstructures are observed to show bimodal. Dynamic recrystallization can take place in the b region irrespective of starting deformed structures.

关键词： titanium alloys hot pressing deformation microstructural evolution activation energy

Inducible overexpression of porcine homeobox A10 in the endometrium of transgenic mice

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Journal of Integrative Agriculture 2016年第6期15卷 1338-1344页

作者： LIN Rui-yi WU Di ZHAO Chang-zhi chen shang-shang XIAO Qian LI Xin-yun ZHAO Shu-hong Key Lab of Agricultural Animal Genetics Breeding and Reproduction Ministry of Education/The Cooperative Innovation Center for Sustainable Pig Production Huazhong Agricultural University Wuhan 430070 P.R China College of Animal Science and Technology Northeast Agricultural University Harbin 150030 P.R.China

Homeobox A10 （HOXA 10） is a well-known transcription factor that plays an important role in directing endometrial differ- entiation and establishing the conditions required for implantation. Interestingly, the expression level of HOXAIO may be associated with litter size. To study the effects of the porcine HOXAIO promoter fragment on the expression of HOXAIO gene in vivo, we generated a transgenic mouse model using pronuclear microinjection, and measured the expression of HOXAIO in the endometrium. There was no difference in the expression level of HOXAIO between transgenic and wild- type mice in the absence of hormone stimulation. However, following treatment with progesterone and estradiol benzoate, the expression level of HOXAIO was significantly increased in transgenic mice compared with that of wild-type mice. Fur- thermore, the litter size of transgenic females was larger than that of wild-type females （7.02±1.73 vs. 6.48＋1.85; P=0.14）. Moreover, the difference of litter size was greater in the later parities （7.33±1.62 vs. 6.37±2.02; P=0.08） compared with the first parity （6.76±1.81 vs. 6.61v1.67; P=0.77） between transgenic and wild-type mice. Therefore, our transgenic mouse model provides exciting insights regarding the actions of HOXAIO and its hormone-inducible promoter in vivo. The present study offers valuable proof of principle to develop transgenic pigs with a hormone-inducible promoter regulating HOXAIO to alter litter size.

关键词： porcine HOXA 10 transgenic mice endometrium