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Business Environment and Resource Allocation Based on the Perspective of the National Value Chain

Journal of Systems Science & Complexity 2023年第1期36卷 294-327页

作者： ZOU Wei lei hao Economics and Management School Wuhan UniversityWuhan 430072China

China is actively upgrading its industrial structure through industries transferring between developed and undeveloped areas;however,the overall level of the national value chain is still not high,and the asymmetric competition pattern between the upstream and the downstream has not been ***,this paper establishes a competitive equilibrium model for the production of manufacturing enterprises,with factor price distortion,under the condition of constant returns to *** authors derive the relative distortion coefficients of each factor price,calculate the misallocation indices of capital and labor,and construct an industry resource misallocation ***,this paper applies the regional value-added decomposition model to calculate the national value chain index and matches the market index of the China Market Index Database with the Chinese Industrial Enterprises Database and the Inter-Regional Input-Output Tables through quantitative *** the perspective of the national value chain,the authors study the improvement effect and mechanism of the business environment on the resource allocation in *** study shows that industry resource allocation will be improved by 17.89%if the business environment level is improved by one standard *** effect is most prevalent in the eastern and central regions,not so much in the west;the effect of downstream industries in the national value chain is higher than that of upstream industries;the improvement effect on capital allocation is higher in downstream industries than in the upstream industries;and the improvement effect on labor misallocation is basically the same in both the upstream and the *** with labor intensive industries,capital intensive industries are more influenced by the national value chain,while the effect of upstream industries is *** the same time,it is well documented that participation in the global value chain can improve the efficienc

关键词： Business environment national value chain resource misallocation

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Advances in CO-tolerant anode catalysts for proton exchange membrane fuel cells

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Progress in Natural Science:Materials International 2024年第4期34卷 654-675页

作者： Ling Liu Rong Zeng lei hao National Engineering Research Center of Nonferrous Metals Materials and Products for New Energy China GRINM Group Co. Ltd. GRIMAT Engineering Institute Co. Ltd. General Research Institute for Nonferrous Metals

Pt-based catalysts are often used in a proton exchange membrane fuel cell due to their high activities to oxygen reduction and hydrogen oxidation reaction. However, these catalysts are easily poisoned by CO, resulting in a significant reduction of fuel cell performance. The use of CO-tolerant catalysts can effectively solve this *** CO poisoning mechanism and anti-poisoning strategies were briefly discussed in this article. It mainly focused on the research progress on CO-tolerant catalysts in three aspects: Pt alloy catalysts, metal oxide composite catalysts, and blocking layer covered catalysts. The advantages and limitations of various catalysts in recent years were also discussed. Creating a porous blocking layer covered on the surface of the catalyst can effectively enhance the CO-tolerance of the catalysts which could be a promising approach for developing anti-poison catalysts other than CO-tolerance. Finally, the prospects for future development of CO-tolerant fuel cell catalysts were described.

关键词： PEMFCs CO-tolerance Catalysts

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Microstructure and texture evolution of TRC A8006 alloy by homogenization

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International Journal of Minerals,Metallurgy and Materials 2013年第5期20卷 433-439页

作者： Zhong-wei Chen Jing Zhao Xiao-lei hao State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The microstructure and texture evolution of twin-roll cast A8006 alloy by homogenization were characterized using scanning and transmission electron microscopy, and the microhardness was tested as well. According to the relation- ship between dendritic arm spacing and cooling rate the cooling rate of the as-cast twin-roll cast A8006 sheet of 6 mm in thickness was estimated as 1.48×10^3 K·s^-1. It is found that the grains and the nanostructural precipitates of the twin-roll cast sheet become coarser after homogenization at 580℃ for 4 h in comparison with those after homogenization at 500℃ for 8 h. The textures formed after cold rolling and became weaker during homogenization. The increase in hardness of the as-cast twin-roll cast sheets is related in hardness after homogenization can to the supersaturated a-A1 solid solution and be attributed to the coarsening of grains and fine microstructure, but the decrease Al6Fe（Mn） precipitates.

关键词： aluminum alloys homogenization microstructure textures hardness

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Enhancement of the flux for polypropylene hollow fiber membrane in a submerged membrane-bioreactor by surface modification

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Journal of Environmental Sciences 2006年第6期18卷 1050-1055页

作者： YU Hai-yin lei hao XU Zhi-kang Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education of China Institute of Polymer Science Zhejiang University Hangzhou 310027 China School of Chemistry and Materials Science Anhui Normal University Wuhu 241000 China

To improve its limiting flux and antifouling characteristics in a submerged membrane-bioreactor （SMBR） for wastewater treatment, polypropylene hollow fiber microporous membrane （PPHFMM） was surface-modified by the plasma-induced immobilization of poly （N-vinyl-2-pyrrolidone）（PVP） and the plasma treatment with different gases respectively. Attenuated total reflection-Fourier transform infrared spectroscopy （FT-IR/ATR）, X-ray photoelectron spectroscopy （XPS） and field emission scanning electron microscope （FE-SEM） were used to characterize the structural and morphological changes on the membrane surface. Water contact angle was measured by the sessile drop method. It was found that the water contact angle was 128.8, 72.3, 62.7, 74.4, 79.1, 86.3, and 71.3° for the nascent, PVP-immobilized, air, 02, Ar, CO2 and H2O plasma treated PPHFMM, respectively. The SMBR was operated at fixed transmembrane pressure to determine the limiting flux for the PPHFMM before and after surface modification. Results showed that the limiting flux appeared to be 103, 159, 117, 133, 136, 121 and 152 L/（m^2· h） for the nascent, PVP-immobilized, air, O2, At, CO2 and H2O plasma treated PPHFMM, respectively. After continuous operation for about 50 h in the SMBR, the antifouling characteristics were improved to some extent.

关键词： surface modification polypropylene hollow fiber microporous membrane limiting flux submerged membrane-bioreactor antifouling characteristics

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A Liquid–Solid Interface-Based Triboelectric Tactile Sensor with Ultrahigh Sensitivity of 21.48 kPa-1

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Nano-Micro Letters 2022年第6期14卷 28-38页

作者： Jingya Liu Zhen Wen hao lei Zhenqiu Gao Xuhui Sun Institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123People’s Republic of China

Traditional triboelectric tactile sensors based on solid–solid interface have illustrated promising application prospects through optimization ***,the poor sensitivity and reliability caused by hard contact-electrification still poses challenges for the practical *** this work,a liquid–solid interface ferrofluid-based triboelectric tactile sensor(FTTS)with ultrahigh sensitivity is *** on the fluidity and magnetism of ferrofluid,the topography of microstructure can be flexibly adjusted by directly employing ferrofluid as triboelectric material and controlling the position of outward *** date,an ultrahigh sensitivity of 21.48 k Pa;for the triboelectric sensors can be achieved due to the high spike microstructure,low Young’s modulus of ferrofluid and efficient solid–liquid interface *** detection limit of FTTS of 1.25 Pa with a wide detection range to 390 k Pa was also *** addition,the oleophobic property between ferrofluid and poly-tetra-fluoro-ethylene triboelectric layer can greatly reduce the wear and tear,resulting in the great improvement of ***,a strategy for personalized password lock with high security level has been demonstrated,illustrating a great perspective for practical application in smart home,artificial intelligence,Internet of things,etc.

关键词： Ferrofluid Tactile sensor Triboelectric nanogenerator Microstructure Ultrahigh sensitivity

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Multicomponent induced localized coupling in Penrose tiling for electromagnetic wave absorption and multiband compatibility

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Journal of Materials Science & Technology 2022年第35期130卷 86-92页

作者： Xinran Ma Yuping Duan Lingxi Huang Ben Ma hao lei Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116085China

In the electronic information and intelligent era, microwave absorption materials have been focused on the issue of electromagnetic(EM) pollution, but high-performance absorbers with thin thickness are highly desirable. The positive action between structural design and component selection can be regarded as a function to optimize the microwave loss capacity, which contributes to understanding the response mechanisms from the micro and macro. Therefore, we designed the absorber with quasiperiodic structures of Penrose tiling that has finely engineered the location of maximum absorption peak, the spherical carbonyl iron in thin rhombus, and flakey carbonyl iron in fat rhombus, the effective absorption bandwidth(Reflection Loss ≤ –10 d B) was realized from 6.46 GHz to 15.78 GHz in the 2 mm thickness. The unique arrangement of Penrose tiling can respond alternatingly to EM waves at large scales, and multicomponent coupling is distinctly in the neighboring unit cells. In addition, spraying aluminum pigment as the upper layer, the infrared emissivity is less than 0.35 to meet the complex application *** work opens up novel ideas on quasiperiodic structure combined multicomponent and injects infinite vitality to provide prospects for broadband responsive and high-efciency EM absorbers.

关键词： Microwave absorber Penrose tiling Carbonyl iron Localized coupling

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Association of serum pepsinogen with degree of gastric mucosal atrophy in an asymptomatic population

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World Journal of Clinical Cases 2021年第31期9卷 9431-9439页

作者： hao-lei Cai Yu-Ling Tong Department of Surgery The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina International Healthcare Center The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

BACKGROUND Atrophic gastritis is a precancerous lesion of the *** has been reported that pepsinogen(PG)can reflect the morphology and function of the gastric mucosa,and it is therefore used as a marker for the early diagnosis of atrophic *** To evaluate the diagnostic value of serum PG for degree of gastric mucosal atrophy in asymptomatic Chinese upon physical *** Medical data were collected from subjects who underwent transnasal gastroscopy between October 2016 and October *** each study subject,serum PG levels and presence of Helicobacter pylori(***)infection were *** was evaluated using the Operative Link for Gastritis Assessment(OLGA)classification and Operative Link on Gastric Intestinal Metaplasia Assessment(OLGIM)*** statistical analyses were carried out using SPSS statistical *** A total of 2256 subjects were enrolled and 1922 cases were finally included in the *** on the OLGA grading system,the levels of PGI were slightly decreased,while those of PGII were slightly *** PGI/PGII ratio(PGR)was reduced with increasing *** association between PG and OLGA grading was higher compared with that between PG and the OLGIM grading *** with the OLGA-0 group,a statistically significant difference was observed in the mean age of OLGA-Ⅰ,Ⅲ,and Ⅳ groups(P<0.05).In the ***-positive subjects,the PGR levels were notably lower in the OLGA-Ⅰ,Ⅱ,and Ⅲ groups compared with the OLGA-0 group(P<0.05).***-positive subjects exhibited significantly higher PGI and PGII serum levels and a significantly lower PGR compared with ***-negative patients in different OLGA groups(P<0.05).CONCLUSION Serum PG levels may represent a non-invasive screening marker for gastric mucosal atrophy in asymptomatic subjects.

关键词： Pepsinogen Helicobacter pylori Operative Link for Gastritis Assessment Atrophic gastritis Gastric mucosal atrophy Biomarker

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Gaussian sampling of lattices for cryptographic applications

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Science China(Information Sciences) 2014年第7期57卷 154-161页

作者： HU YuPu lei hao WANG FengHe ZHANG WenZheng State Key Laboratory of Integrate Services Networks Xidian University Security and Privacy Lab Huawei Technologies Co.LTD. The 30th Research Institute of China Electronics Technology Group Corporation

Gaussian sampling is the major class of algorithms for solving the close vector problem(CVP)of *** this paper we present a novel Gaussian sampling algorithm,which has the same cryptographic applications with original Gaussian sampling *** novel Gaussian sampling algorithm has smaller deviations,meaning smaller space sizes of lattice based public-key *** shape of our novel algorithm is almost repeated implementations of original algorithm,with random repeating *** result is that the deviation can be reduced to 0.64～0.75 of that of original Gaussian sampling algorithm without clearly increasing the average time cost.

关键词： lattice based public-key cipher CVP Gaussian sampling

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Performance limitations in trajectory tracking control for air-breathing hypersonic vehicles

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Chinese Journal of Aeronautics 2019年第1期32卷 167-175页

作者： Boyi CHEN Yanbin LIU Haidong SHEN hao lei Yuping LU College of Astronautics Nanjing University of Aeronautics and Astronautics College of Automation Engineering Nanjing University of Aeronautics and Astronautics

An integrated approach that considers the performance limitations of tracking control systems for air-breathing hypersonic vehicles is proposed. First, a set of ascent trajectories is obtained as candidates for tracking control through a trajectory design method that considers the available acceleration. Second, the basic theory of performance limitations, which is adopted to calculate the limits on control performance through the trajectory, is integrated. The openloop dynamics of air-breathing hypersonic vehicles is responsible for these limits on the control system. Comprehensive specifications on stability, tracking accuracy, and robustness are derived, and the flight envelope with constraints and control specifications is identified. Simulation results suggest that trajectory design should consider restrictions on control performance to obtain reliable solutions.

关键词： Bandwidth constraints Hypersonic vehicles Performance limitations Robust performance Trajectory tracking control

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Lattice-based certificateless encryption scheme

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Frontiers of Computer Science 2014年第5期8卷 828-836页

作者： Mingming JIANG Yupu HU hao lei Baocang WANG Qiqi LAI State Key Laboratory of Integrated Service Networks Xidian University Xi'an 710071 China Security and Privacy Lab CRDU Huawei Technologies Co. LTD. Beijing 100095 China

Certificateless public key cryptography （CL- PKC） can solve the problems of certificate management in a public key infrastructure （PKI） and of key escrows in identity-based public key cryptography （ID-PKC）. In CL- PKC, the key generation center （KGC） does not know the private keys of all users, and their public keys need not be cer- tificated by certification authority （CA）. At present, however, most certificateless encryption schemes are based on large in- teger factorization and discrete logarithms that are not secure in a quantum environment and the computation complexity is high. To solve these problems, we propose a new certificate- less encryption scheme based on lattices, more precisely, us- ing the hardness of the learning with errors （LWE） problem. Compared with schemes based on large integer factoriza- tion and discrete logarithms, the most operations are matrix- vector multiplication and inner products in our scheme, our approach has lower computation complexity. Our scheme can be proven to be indistinguishability chosen ciphertext attacks （IND-CPA） secure in the random oracle model.

关键词： lattice-based cryptography LWE identity-based encryption (IBE) post-quantum cryptography certifi-cateless encryption

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