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Industrial Production of Catalyst for Removing Trace Olefins from Aromatics

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China Petroleum Processing & Petrochemical Technology 2012年第2期14卷 44-49页

作者： Pu xin shi Li The State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237

A novel additive incorporated into the catalyst for removing trace olefins from aromatics was proposed, and under the laboratory conditions the lifetime of the catalyst was increased from 5 h to 8 h upon specifying the conversion of the olefins equating to more than 55% as a criterion. Catalyst production, which was named ROC, has been successfully scaled up from laboratory formulations to commercial scale manufacture and over 100 tons of catalyst had been produced. The superiority in catalytic activity was identified by the evaluation tests of the ROC catalyst based on whatever kind of feedstocks (with their bromine index ranging from 400 mgBr/100g to 1 200 mgBr/100g) being used as the feedstock. The X-ray diffraction patterns had verified that the additive was highly dispersed on the surface of catalyst; the GC-FID analysis results showed that the ROC catalyst could increase the xylene content; the pyridine-FTIR spectroscopic analyses suggested that the additive could increase the amount of the weak L acids, which was the main cause leading to enhancement of the catalyst activity.

关键词： olefins aromatics industrial production catalyst

Fast and accurate visual odometry from a monocular camera

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Frontiers of Computer Science 2019年第6期13卷 1326-1336页

作者： xin YANG Tangli XUE Hongcheng luo Jiabin GUO School of Electronic Information and Communications Huazhong University of Science and TechnologyWuhan 430074China

This paper aims at a semi-dense visual odometry system that is accurate,robust,and able to run realtime on mobile devices,such as smartphones,AR glasses and small *** key contributions of our system include:1)the modified pyramidal Lucas-Kanade algorithm which incorporates spatial and depth constraints for fast and accurate camera pose estimation;2)adaptive image resizing based on inertial sensors for greatly accelerating tracking speed with little accuracy degradation;and 3)an ultrafast binary feature description based directly on intensities of a resized and smoothed image patch around each pixel that is sufficiently effective for relocalization.A quantitative evaluation on public datasets demonstrates that our system achieves better tracking accuracy and up to about 2X faster tracking speed comparing to the state-of-the-art monocular SLAM system:*** the relocalization task,our system is 2.0X∼4.6X faster than DBoW2 and achieves a similar accuracy.

关键词： visual odometry mobile devices direct tracking relocalization inertial sensing binary feature

Re-epithelialization resulted from prostate basal cells in canine prostatic urethra may represent the ideal healing method after two-micron laser resection of the prostate

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Asian Journal of Andrology 2015年第5期17卷 831-838,I0010-I0011页

作者： Ying Cao Guang-Heng luo Lei luo Xiu-Shu Yang Jian-xin Hu Hua shi Ping Huang Zhao-Lin Sun Shu-Jie Xia Department of Urology Shanghai First People's Hospital Shanghai Jiaotong University Shanghai 200080 China Department of Urology Guizhou Provincial People's Hospital Guiyang 550002 China Department of Pathology Guizhou Provincial People's Hospital Guiyang 550002 China

The purpose of this study is to characterize the re-epithelialization of wound healing in canine prostatic urethra and to evaluate the effect of this re-epithelialization way after two-micron laser resection of the prostate （TmLRP）. TmLRP and partial bladder neck mucosa were performed in 15 healthy adult male crossbred canines. Wound specimens were harvested at 3 days, and 1, 2, 3, and 4 weeks after operation, respectively. The histopathologic characteristics were observed by hematoxylin and eosin staining. The expression of cytokeratin 14 （CK14）, CK5, CK18, synaptophysin （Syn）, chromogranin A （CgA）, uroplakin, transforming growth factor-β1 （TGF-β1）, and TGF-β type Ⅱ receptor in prostatic urethra wound were examined by immunohistochemistry and real-time polymerase chain reaction, respectively. Van Gieson staining was performed to determine the expression of collagen fibers in prostatic urethra and bladder neck would. The results showed that the re-epithelialization of the prostatic urethra resulted from the mobilization of proliferating epithelial cells from residual prostate tissue under the wound. The proliferating cells expressed CK14, CK5, but not CK18, Syn, and CgA and re-epithelialize expressed uroplakin since 3 weeks. There were enhanced TGF-β1 and TGF-β type Ⅱ receptor expression in proliferating cells and regenerated cells, which correlated with specific phases of re-epithelialization. Compared with the re-epithelialization of the bladder neck, re-epithelialization of canine prostatic urethra was faster, and the expression of collagen fibers was relatively low. In conclusion, re-epithelialization in canine prostatic urethra resulted from prostate basal cells after TmLRP and this re-epithelialization way may represent the ideal healing method from anatomic repair to functional recovery after injury.

关键词： basal cell benign prostate hyperplasia re-epithelialization two-micron laser wound healing

Influence of Damage Evolution on the Failure Surface of Concrete

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Wuhan University Journal of Natural Sciences 2006年第3期11卷 657-661页

作者： luo xin WEI Jun School of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074Hubei China

The damage which represents the alternation of internal slate of material was introduced to concrete strength theory according to the theory of mechanics of continuous medium and the failure criterion of deteriorated concrete was diseussions. In the tests, ultrasonic velocity is used to establish the damage variable and to establish the damage-eoupled failure criterion of concrete under freeze-thaw. The results show that the failure surface is gradually shrinking with the increase of freeze-thaw times. Furthermore, by the comparison between the theoretical data and the testing data from the literature, the rationality of strength theory proposed in the paper acquire confirmation. The damage-coupled failure criterion presented here can indicate the influence of damage evolution on the failure surface of concrete.

关键词： conerete failure eriterion damage freezethaw supersonic veloeity twin-shear strength theory

Numerical study on shock-dusty gas cylinder interaction

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Acta Mechanica Sinica 2019年第4期35卷 740-749页

作者： Jingyue Yin Juchun Ding Xisheng luo xin Yu Beijing Institute of Applied Physics and Computational Mathematics Beijing 100094 China Advanced Propulsion Laboratory Department of Modern Mechanics University of Science and Technology of China Hefei 230026 China

The interaction of a planar shock wave with a dusty-gas cylinder is numerically studied by a compressible multi-component solver with an adaptive mesh refinement technique. The influence of non-equilibrium effect caused by the particle relaxation, which is closely related to the particle radius and shock strength, on the evolution of particle cylinder is emphasized. For a very small particle radius, the particle cloud behaves like an equilibrium gas cylinder with the same physical properties as those of the gas-particle mixture. Specifically, the transmitted shock converges continually within the cylinder and then focuses at a region near the downstream interface, producing a local high pressure zone followed by a particle jet. Also, noticeable secondary instabilities emerge along the cylinder edge and the evident particle roll-up causes relatively large width and height of the shocked cylinder. As the particle radius increases, the flow features approach those of a frozen flow of pure air, e.g., the transmitted shock propagates more quickly with a weaker strength and a smaller curvature, resulting in an increasingly-weaken shock focusing and particle jet. Also, particles would escape from the vortex core formed at late stages due to the larger inertia, inducing a greater particle dispersion. It is found that a large particle radius as well as a strong incident shock can facilitate such particle escape. The theory of luo et al.(J. Fluid Mech., 2007) combined with the SZ circulation model ( J. Fluid Mech., 1994) can reasonably explain the high dependence of particle escape on the particle radius and shock strength.

关键词： Dusty-gas cylinder Non-equilibrium effect Shock wave Instability

CFD-PBM simulation of bubble coalescence and breakup in top blown-rotary agitated reactor

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Journal of Iron and Steel Research International 2022年第2期29卷 223-236页

作者： Pin Shao shi-xu Liu xin-cheng Miao School of Materials and Metallurgy University of Science and Technology LiaoningAnshan114051LiaoningChina

Gas–liquid flow and bubble coalescence and breakup behavior were studied in a top blown-rotary agitated reactor for *** important models of bubble coalescence and breakup mechanisms were considered and compared,and water model experiment was carried out to verify and optimize the mathematical *** influence of different operating parameters including paddle arrangement,stirring speed and top blowing flow rate on the bubble size and distribution was *** results show that the predicted bubble size and distribution present a good agreement with the experimental results using the improved luo–Laakkonen combination *** the position of the stirring paddle moves from the center to the side wall,the bubble distribution in the reactor becomes more uniform,and the bubble size gradually *** the increase in the paddle rotation speed,the bubble size ***,this effect begins to weaken when the paddle rotation speed exceeds 150 r/*** the top blowing flow rate will increase the bubble size in the reactor,but it has a weak effect on bubble *** the top blowing rate exceeds 2.0 m^(3)/h,the bubble size in the bath is basically not less than 5 mm.

关键词： Top blown-rotary agitated reactor Bubble coalescence Bubble breakup Bubble size CFD-PBM Numerical simulation

Effects of porous oxide layer on performance of Pd-based monolithic catalysts for 2-ethylanthraquinone hydrogenation

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Chinese Journal of Chemical Engineering 2016年第11期24卷 1570-1576页

作者： xin shi Enxian Yuan Guozhu Liu Li Wang Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin 300072 China

Pd/oxide/cordierite monolithic catalysts(oxide = Al_2O_3, SiO_2 and SiO_2\\Al_2O_3) were prepared by the impregnation method. The results of ICP, XRD, SEM–EDX, XPS and N_2 adsorption–desorption measurements revealed that the Pd penetration depth increased with increasing the thickness of oxide layer, and the catalysts with Al_2O_3 layers had the larger pore size than those with SiO_2 and SiO_2\\Al_2O_3 layers. Catalytic hydrogenation of 2-ethylanthraquinone(eA Q), a key step of the H_2O_2 production by the anthraquinone process, over the various monolithic catalysts(60 °C, atmosphere pressure) showed that the monolithic catalyst with the moderate thickness of Al_2O_3 layer(about 6 μm) exhibited the highest conversion of e AQ(99.1%) and hydrogenation efficiency(10.0 g·L^(-1)). This could be ascribed to the suitable Pd penetration depth and the larger pore size, which provides a balance between the distribution of Pd and accessibility of active sites by the reactants.

关键词： Monolith Catalyst Hydrogenation Anthraquinone Hydrogen peroxide Pd

Evaluation of tool wear and cutting performance based on FEM simulation

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Chinese Journal of Aeronautics 2021年第4期34卷 140-152页

作者： Zhenyu shi xin LI Ningmin DUAN Qibiao YANG Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationShandong UniversityJinan 250061China School of Mechanical Engineering Shandong UniversityJinan 250061China School of Mechanical Engineering Hubei University of TechnologyWuhan 430000China

An accurate estimation of tool wear morphology can provide the opportunity to investigate the influence of tool wear on cutting performance as well as reduce the overall production ***,tool wear prediction is still a very challenging research *** this paper,a novel method for simulating the actual chip formation and wear evolution thorough the 3 D finite element model has been carried *** order to improve the accuracy of simulation results,the influence of worn tool,stress and temperature distribution on wear rate are *** cutting experiment has been conducted by turning AISI1045 with uncoated carbide tools to validate the accuracy of the proposed *** comparison between experimental and simulation results show good agreement which proves the ability of the proposed model in forecasting the tool *** validated finite element model has been further utilized studying how the worn tool affects the cutting performance including actual cutting rake,stress distribution,cutting force and *** results of this paper not only provide a clear understanding of wear evolution between tool rake face and chip,but also are meaningful to optimize tool design and cutting parameters.

关键词： Finite element method Friction model Machining Stress distribution Wear

A method for determining the spatial pattern of forest trees based on the uniformity theory

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Journal of Forestry Research 2024年第6期35卷 148-159页

作者： Yeqiong shi Xiulong Gao Chunling Lang Chuanwen luo College of Computer Science and Information Engineering Harbin Normal UniversityHarbin 150040People’s Republic of China College of Vocation and Technical Education Guangxi Science and Technology Normal UniversityLaibin 546199People’s Republic of China College of Mathematics and Computer Science Guangxi Science and Technology Normal UniversityLaibin 546199People’s Republic of China College of Forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China

The spatial pattern of trees is an important feature of forests,and different spatial patterns of trees exhibit different ecological *** has confirmed that natural forests with random patterns have higher biodiversity and stronger resistance to unstable factors such as pests and *** if they are disturbed or destroyed by unstable factors such as pests and diseases,they can still recover and rescue themselves;while artificial forests with uniform and clustered patterns have lower biodiversity and are susceptible to unstable factors such as pests and *** once pests and diseases occur,it’s more difficult for them to *** order to promote the healthy and stable develop-ment of the forestry industry and protect the diversity of the biological environment,it is necessary to protect the random pattern of natural forests from being destroyed in the process of forest management,while effectively transforming the spatial pattern of artificial forests into a random ***,in order to ensure the convenient and accurate determination of the type of forest spatial pattern,research on methods for determining forest spatial pattern has become particularly *** on the theory of uniformity,this study proposes definitions and related theories of included exclusive sphere,included exclusive body,included random pattern,and included *** the guidance of the definition of inclusion uniformity and related theories,and by using mathematical method,it is proved that the uniformity of inclusion(CL)is asymptotically subject to the Eq.18,Therefore,the relationship between the included uniformity(CL)and the number of trees in the sample plot was established,and the corresponding relationship formula was obtained,and then the determination of the spatial pattern type of trees was completed by using the corresponding relationship *** rigorous reasoning and case verification,the determination method of forest spat

关键词： Uniformity Forest spatial pattern Contained exclusive sphere Co correlation coefficient Included Uniformity