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Chloroaluminate ionic liquid catalyzed isomerization of n-pentane in the presence of product distribution improver

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Petroleum Science 2011年第2期8卷 219-223页

作者： Xia Rong＇an Zhang rui meng Xianghai Liu Zhichang meng Jiaying Xu Chunming State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China

The ionic liquid Et3NHC1-2AIC13 can catalyze the isomerization of n-pentane. This paper investigates the ionic liquid catalyzed isomerization performance of n-pentane with several product distribution improvers in an autoclave. The product distribution of n-pentane isomerization could be improved by such improvers as benzene, cyelohexane, and methyl cyclohexane at the expense of conversion of n-pentane. The optimal product distribution improver was determined to be cyclohexane. The yield of isomerate and the selectivity of liquid isoalkanes increased, whereas the conversion of n-pentane decreased, with increasing cyclohexane amount. At the same conversion of n-pentane, the research octane number （RON） of liquid product, with cyclohexane amount of 0.5 wt%, was about 1.3 higher than that without cyclohexane. At the same reaction conditions, the presence of cyclohexane enhanced the yield of isomerate, the selectivity of liquid isoalkanes, and the RON of the liquid product, but reduced the conversion of n-pentane.

关键词： Isomerization ionic liquid improver pentane cyclohexane

Deciphering and integrating invariants for neural operator learning with various physical mechanisms

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National Science Review 2024年第4期11卷 111-122页

作者： rui Zhang Qi meng Zhi-Ming Ma Academy of Mathematics and Systems Science Chinese Academy of Sciences(CAS) Microsoft Research

Neural operators have been explored as surrogate models for simulating physical systems to overcome the limitations of traditional partial differential equation(PDE) solvers. However, most existing operator learning methods assume that the data originate from a single physical mechanism, limiting their applicability and performance in more realistic scenarios. To this end, we propose the physical invariant attention neural operator(PIANO) to decipher and integrate the physical invariants for operator learning from the PDE series with various physical mechanisms. PIANO employs self-supervised learning to extract physical knowledge and attention mechanisms to integrate them into dynamic convolutional *** to existing techniques, PIANO can reduce the relative error by 13.6%–82.2% on PDE forecasting tasks across varying coefficients, forces or boundary conditions. Additionally, varied downstream tasks reveal that the PI embeddings deciphered by PIANO align well with the underlying invariants in the PDE systems, verifying the physical significance of PIANO.

关键词： neural operator PDE solver contrastive learning physical invariants

Application of Reproducing Kernel Particle Method in an Analysis of Elasto-plastic Deformation Under Taylor Impact

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Journal of China University of Mining and Technology 2006年第4期16卷 485-489页

作者： ZHAO Guang-ming SONG Shun-cheng meng Xiang-rui Department of Resource Exploration and Management Engineering Anhui University of Science and Technology Huainan Anhui 232001 China Department of Applied Mechanics and Engineering Southwest Jiaotong University Chengdu Sichuan 610031 China

The Reproducing Kernel Particle Method (RKPM) is one of several new meshless numerical methods de- veloped internationally in recent years. The ideal elasto-plastic constitutive model of material under a Taylor impact is characterized by the Jaumann stress- and strain-rates. An updated Lagrangian format is used for the calculation in a nu- merical analysis. With the RKPM, this paper deals with the calculation model for the Taylor impact and deduces the control equation for the impact process. A program was developed to simulate numerically the Taylor impact of projec- tiles composed of several kinds of material. The simulation result is in good accordance with both the test results and the Taylor analysis outcome. Since the meshless method is not limited by meshes, it is believed to be widely applicable to such complicated processes as the Taylor impact, including large deformation and strain and to the study of the dy- namic qualities of materials.

关键词： Reproducing Kernel Particle Method Taylor impact large deformation meshless method

Analysis of Phthalate Esters in Air, Soil and Plants in Plastic Film Greenhouse

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Chinese Chemical Letters 2002年第6期13卷 557-560页

作者： Xi Kui WANG Wei Lin GUO Ping rui meng Jia An GAN College of Chemistry and Environmental Science University of JinanJinan 250022

The phthalate esters such as DMP, DEP, DBP and DEHP in air, soil and plant samples in plastic film greenhouse were clean up with fine silica gel column and determined with HPLC. It was found that the concentrations of PEs in air and soil samples in plastic film greenhouse are much higher than those of contrast samples. But concentrations of PEs in plants in plastic film greenhouse are not remarkably affected by the pollution of air and soil.

关键词： Phthalate esters plastic film greenhouse analysis.

Simplified design of nonlinear damper parameters and seismic responses for long-span cable-stayed bridges with nonlinear viscous dampers

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1103-1116页

作者： Huihui LI Lifeng LI rui HU meng YE College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering Shenzhen UniversityShenzhen 518060China College of Civil Engineering Hunan UniversityChangsha 410082China

Viscous dampers are widely used as passive energy dissipation devices for long-span cable-stayed bridges for mitigation of seismic load-induced ***,complicated finite element(FE)modeling,together with repetitive and computationally intensive nonlinear time-history analyses(NTHAs)are generally required in conventional design *** streamline the preliminary design process,this paper developed a simplified longitudinal double degree of freedom model(DDFM)for single and symmetric twin-tower cable-stayed *** on the proposed simplified longitudinal DDFM,the analytical equations for the relevant mass-and stiffness-related parameters and longitudinal natural frequencies of the structure were derived by using analytical and energy *** of the relationship between the nonlinear viscous damper parameters and the equivalent damping ratio was achieved through the equivalent linearization ***,the analytical equations of longitudinal seismic responses for long-span cable-stayed bridges with nonlinear viscous dampers were *** on the developed simplified DDFM and suggested analytical equations,this paper proposed a simplified calculation framework to achieve a simplified design method of nonlinear viscous damper ***,the effectiveness and applicability of the developed simplified longitudinal DDFM and the proposed calculation framework were further validated through numerical analysis of a practical cable-stayed ***,the results indicated the following.1)For the obtained fundamental period and longitudinal stiffness,the differences between results of the simplified longitudinal DDFM and numerical analysis were only 2.05%and 1.5%,respectively.2)Relative calculation errors of the longitudinal girder-end displacement and bending moment of the bottom tower section of the bridge obtained from the simplified longitudinal DDFM were limited to less than 25%.3)The equivalent damping ratio of nonline

关键词： cable-stayed bridges viscous dampers simplified analytical model equivalent damping ratio seismic mitigation

Modeling Long- and Short-Term Service Recommendations with a Deep Multi-Interest Network for Edge Computing

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Tsinghua Science and Technology 2024年第1期29卷 86-98页

作者： rui Yuan Shunmei meng ruihan Dou Xinna Wang Department of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210056China Faculty of Mathematics University of WaterlooWaterloo N2L 3G1Canada

Edge computing platforms enable application developers and content providers to provide context-aware services(such as service recommendations)using real-time wireless access network *** to recommend the most suitable candidate from these numerous available services is an urgent ***-through rate(CTR)prediction is a core task of traditional service ***,many existing service recommender systems do not exploit user mobility for prediction,particularly in an edge computing *** this paper,we propose a model named long and short-term user preferences modeling with a multi-interest network based on user *** uses a logarithmic network to capture multiple interests in different fields,enriching the representations of user short-term *** terms of long-term preferences,users'comprehensive preferences are extracted in different periods and are fused using a nonlocal *** experiments on three datasets demonstrate that our model relying on user mobility can substantially improve the accuracy of service recommendation in edge computing compared with the state-of-the-art models.

关键词： recommender system logarithmic network nonlocal network

Third-Order Stokes Wave Solutions of the Free Surface Capillary- Gravity Wave and the Interfacial Internal Wave

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China Ocean Engineering 2017年第6期31卷 781-787页

作者： meng rui-jun CUI Ji-feng CHEN Xiao-gang ZHANG Bao-le ZHANG Hong-bo College of Science Inner Mongolia University of Technology Hohhot 010051 China

Based on the Stokes wave theory, the capillary-gravity wave and the interfacial internal wave in two-layer constant depth＇s fluid system are investigated. The fluids are assumed to be incompressible, inviscid and irrotational. The third-order Stokes wave solutions are given by using a perturbation method. The results indicate that the third-order solutions depend on the surface tension, the density and the depth of each layer. As expected, the first-order solutions are the linear theoretical results （the small amplitude wave theoretical results）. The second-order and the third-order solutions describe the nonlinear modification and the nonlinear interactions. The nonlinear impact appears not only in the n （n〉~2） times＇ high frequency components, but also in the low frequency components. It is also noted that the wave velocity depends on the wave number, depth, wave amplitude and surface tension.

关键词： surface tension capillary-gravity waves Stokes wave theory third-order Stokes wave solutions

Pulmonary alveolar proteinosis complicated with tuberculosis:A case report

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World Journal of Clinical Cases 2021年第17期9卷 4400-4407页

作者： Hao Bai Zi-rui meng Bin-Wu Ying Xue-Rong Chen Department of Laboratory Medicine West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Respiratory and Critical Care Medicine West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Pulmonary alveolar proteinosis(PAP)is a rare lung disease characterized by the accumulation of phospholipoproteinaceous material in the *** of PAP complicated with tuberculosis are much more complex and have rarely been well *** SUMMARY We describe a 21-year-old Han Chinese patient with suspicious lung infection associated with mild restrictive ventilatory dysfunction and diffusion *** resolution computed tomography revealed a“crazy-paving”appearance and multiple pulmonary miliary nodules around the *** lavage demonstrated a small amount of periodic acid-Schiff positive proteinaceous materials.A serological test for the presence of a Mycobacterium tuberculosis antibody and an interferon-gamma release assay were both *** patient received a standard course of first-line anti-tuberculosis treatment after diagnostic bronchoalveolar *** date,clinical remission has been achieved and maintained for five *** In summary,the diagnosis of PAP complicated with tuberculosis was supported by a combination of clinical manifestations,imaging,pulmonary function,laboratory examinations,bronchoalveolar lavage,*** case highlighted that diagnostic bronchoalveolar lavage in combination with anti-tuberculosis treatment is a safe and effective option for mild PAP patients with tuberculosis.

关键词： Pulmonary alveolar proteinosis Pulmonary tuberculosis Bronchoalveolar lavage Case report

快针结合作业疗法治疗痉挛型脑瘫患儿手功能障碍:随机对照试验

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中国针灸 2024年第2期44卷 149-152页

作者：吴娟妹尹林林黄信萍陈方川吴莹莹孟蕊谢鸿翔宁波市康复医院儿童康复中心浙江宁波315000 浙江省康复与运动医学研究所儿童康复与运动医学研究分所宁波315000

目的:比较快针、留针结合作业疗法与单纯作业疗法治疗痉挛型脑瘫患儿手功能障碍的临床疗效。方法:将75例痉挛型脑瘫患儿随机分为快针组(25例,脱落1例)、留针组(25例,脱落1例)和作业疗法组(25例)。作业疗法组只进行作业疗法治疗,每次20 ... 详细信息

目的:比较快针、留针结合作业疗法与单纯作业疗法治疗痉挛型脑瘫患儿手功能障碍的临床疗效。方法:将75例痉挛型脑瘫患儿随机分为快针组(25例,脱落1例)、留针组(25例,脱落1例)和作业疗法组(25例)。作业疗法组只进行作业疗法治疗,每次20 min。快针组予针刺(不留针)结合作业疗法,留针组予针刺(留针)结合作业疗法,针刺取双侧合谷、后溪、鱼际、外关、肩髃等,留针组留针30 min。以上治疗均每日1次,每周5次,共治疗12周。观察各组患儿治疗前后精细运动评定量表(FMFM)评分、Peabody运动发育量表(第2版)(PDMS-2)评分,比较快针组与留针组针刺安全性。结果:治疗后,各组患儿FMFM、PDMS-2评分较治疗前升高(P<0.01),快针组和留针组FMFM、PDMS-2评分均高于作业疗法组(P<0.05,P<0.01)。快针组针刺异常情况发生率为0.3%(5/1 440),低于留针组的1.4%(20/1 440,P<0.05)。结论:针刺结合作业疗法改善痉挛型脑瘫患儿手功能障碍的临床疗效优于单纯作业疗法,且快针与留针疗效无差异,但快针的安全性较留针更好。

关键词：痉挛型脑瘫手功能障碍针刺快针留针作业疗法随机对照试验