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Journal of Iron and Steel Research International 2015年第4期22卷 324-329页

作者： Xiao-juan ZHEN Pei-qing LA Cui-ling LI su-lei hu State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of Technology

A simple method was developed to produce the nanocrystalline pure iron by aluminothermic reaction cast- ing. The mierostructure of the iron was investigated by optical microseope （OM）, transmission electron microscope （TEM）, electron probe micro-analyzer （EPMA）, scanning electron microscope （SEM） and X-ray diffraction （XRD）. The mechanical performances of nanoerystalline pure iron were tested. It is found that the pure iron consists of nanoerystalline ferrite. For different substrates of eopper and glass, the average grain size of the ferrite was 38 and 35 nm, respectively, which is larger on copper substrate than that on glass. The hardness, compressive strength, tensile strength, and total elongation are 167 and 137 HB, 400 and 500 MPa, 243 and 185 MPa, 16% and 10% on copper substrate and glass suhstrate, respectively. The hardness, tensile strength and total elongation are all larger on copper substrate than those on glass substrate, while the eompressive strength is lower. The large supercooling in the product solidification provides the condition for high nucleation rate and thus leads to nano-grained austenite and final nano-grained ferrite transformed from those small austenite grains.

关键词： nanocrystalline aluminothermic reaction casting pure iron substrate microstructure mechanical property

Effect of parenteral and early intrajejunal nutrition on pancreatic digestive enzyme synthesis, storage and discharge in dog models of acute pancreatitis

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World Journal of Gastroenterology 2007年第7期13卷 1123-1128页

作者： huan-Long Qin Zhen-Dong su lei-Guang hu Zai-Xian Ding Qing-Tian Lin Institute of Parenteral Nutrition and EnteralNutrition Department of Surgery Shanghai Jiaotong UniversityAffiliated Sixth People's Hospital Yishan Rd. 600 Shanghai200233 China

AIM： To study the effect of early intrajejunal nutrition on enzyme-protein synthesis and secretion during acute pancreatitis. METHODS： Fifteen dogs were randomly divided into parenteral nutrition （n = 7） and early intrajejunal nutrition groups （n = 8）. An acute pancreatitis model was induced by injecting 5% sodium taurocholate and trypsin into the pancreas via the pancreatic duct. Intrajejunal nutrition was delivered with a catheter via a jejunostomy tube after the model was established for 24 h. On d 1 and 7 and at the beginning of nutritional support, radioactive tracing and electron microscopes were used to evaluate the enzyme-protein synthesis in acinar cells, the subcellular fractionation and the change in zymogen granules after 1.85 × 10^6 Bq L-3H phenylalanine was infused at 30, 60, 120, and 180 min. REsuLTS： The 3H radioactivity in pancreatic acinar cells reached its peak level at 60 min, and the contents in the early intrajejunal nutrition group were higher than those in the parenteral nutrition group, which were then decreased. The mean number and area of zymogen granules did not show any significant statistical difference in both groups on d i or on d 7 （P 〉 0.05）. CONCLUSION： Early intrajejunal nutrition might be effective in dogs with acute pancreatitis.

关键词： Parenteral nutrition Enteral nutrition Digestive enzyme Acute pancreatitis

Comparison of bulk snow density measurements using different methods

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Advances in Climate Change Research 2024年第4期15卷 658-668页

作者： Hang su Xin-Yue ZHONG Bin CAO Yuan-Tao hu lei ZHENG Tingjun ZHANG State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Key Laboratory of Remote Sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Tibetan Plateau Earth System Environment and ResourcesNational Tibetan Plateau Data CenterInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Climate Centre of Shaanxi Province Xi'an71000China School of Geospatial Engineering and Science Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Key Laboratory of Westem China's Environmental Systems(Ministry of Education).College of Earth and Environmental Sciences Lanzhou Universiny Lanzhou 730000China

Snow density is one of the basic properties used to describe snow cover characteristics,and it is critical for remote sensing retrieval,water resources assessment and modeling *** are many instruments available to measure snow density in ***,there are mea-surement errors of snow density for bulk and layers or gravimetric and electronic instruments,which may affect the accuracy of remote sensing retrieval and model *** in China,due to the noticeable heterogeneity of snowpacks,it is necessary to evaluate in detail the performance and applicability of snow density instruments in different snowpack *** study evaluated the performance of different snow density instruments:the Federal Sampler,the model VS-43 snow density cylinder(VS-43),the wedge snow density cutter(WC1000 and WC25O),and the Snow *** average bulk snow density of all instrument measurements was set as the reference value for *** results showed that as compared with the reference,the VS-43 cylinder presented the best performance for bulk snow density measurement in the measured range with the lowest RMSE(11 kg m-3),BIAS(3 kg m-3),and MRE(1.6%).For layer observation,bulk snow density was overestimated by 8.1%with WC1000 and underestimated by 11.4%with Snow Fork which was the worst performance compared with the reference value,and there were greater measurement errors of snow density in the depth hoar than other snow *** with grassland,the uncertainty of snow density measurements was slightly lower in ***,the Federal Sampler and VS-43 cylinder are more suitable for bulk snow density measurement in deep snowpack regions across China,and it is recommended to use WC1000,WC250 and Snow Fork to measure the snow density of snow layers in the snow stratigraphy.

关键词： Snowdensity Measurement Uncertainty comparison

Coupled conditional nonlinear optimal perturbations and their application to ENSO ensemble forecasts

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Science China Earth Sciences 2024年第3期67卷 826-842页

作者： Wansuo DUAN lei hu Rong FENG LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Limitations are existed in current ensemble forecasting initial perturbation methods for describing the interactions among various spheres of the Earth system. In this study, a new method is proposed, namely, the coupled conditional nonlinear optimal perturbation(C-CNOP) method, which incorporates multisphere interactions much appropriately. The El Nino-Southern Oscillation(ENSO) is a typical ocean-atmosphere “coupling”(or “interaction”) phenomenon. The C-CNOP method is applied to ensemble forecasting of ENSO. It is demonstrated that the C-CNOP method can generate coupled initial perturbations(CPs) that appropriately consider initial ocean-atmosphere coupling uncertainty for ENSO ensemble forecasts. Results reveal that the CPs effectively improve the ability of ENSO ensemble-mean forecasts in both temporal variability of Nio3.4 sea surface temperature anomalies(SSTAs) and spatial variability of ENSO mature-phase SSTAs. Notably, despite the weakest ocean-atmosphere coupling strength in the tropical Pacific occurring during the boreal spring and summer, CPs still capture the uncertainties of this weak coupling when ENSO predictions are initialized at these seasons. This performance of CPs significantly suppresses the rapid increase of ENSO prediction errors due to the high ocean-atmosphere coupling instability during these seasons, and thus effectively extends the lead time of skillful ENSO forecasting. Hence, the C-CNOP method is a suitable initial perturbation approach for ENSO ensemble forecast that can describe initial ocean-atmosphere coupling uncertainty. It is expected that the CCNOP method plays a significant role in predictions of other high-impact climate phenomena, and even future Earth system predictions.

关键词： Ensemble forecast Multisphere interaction Initial perturbations ENSO

Effect of Central Multiphase Microstructure of Thick Plates on Work Hardening and Crack Propagation

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 325-338页

作者： lei hu Liqin Zhang Feng hu Kuan Zheng Guohong Zhang Collaborative Innovation Center for Advanced Steels Wuhan University of Science and TechnologyWuhan430081China Department of Applied Physics Wuhan University of Science and TechnologyWuhan430081China Analysis and Testing Center Wuhan University of Science and TechnologyWuhan430081China

The effect of multiphase microstructure in the center segregation zones(CSZ)of high-strength steel thick plates on work hardening characteristics and crack initiation/propagation were *** was correlated with deformation damage behavior by using Taylor factor(TF)gradients,kernel average misorientation(KAM),and geometric necessary dislocation(GND)*** results show that the segregation leads to a mixed structure of ferrite(soft phase)and martensite/bainite(hard phase)in the center of the thick *** to the 1/4 thickness(1/4 T)region,grain refinement occurred in the CSZ,with KAM values increasing from 0.24 to 0.49 and a decrease in the proportion of high-angle grain boundaries(>15°)from 77.4 to 51.8%.In the process of deformation,due to the influence of grain refinement and adjacent martensite/bainite,ferrite grains were divided into structural units with different TF *** higher KAM value and GND density at the interface between soft/hard phases resulted in severe work *** addition,the presence of micron-sized inclusions in the CSZ caused local strain concentration and non-continuous deformation of the matrix,which induced crack *** fracture surface showed a mixed mode of brittle cleavage fracture and ductile fracture.

关键词： Thick plate Center segregation zone Multiphase microstructure Taylor factor Crack propagation

SAT-Based Automatic Searching for Differential and Linear Trails: Applying to CRAX

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Chinese Journal of Electronics 2024年第1期33卷 72-79页

作者： Yiyi HAN Caibing WANG Zhongfeng NIU lei hu State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences

Boolean satisfiability problem(SAT) is now widely applied in differential cryptanalysis and linear cryptanalysis for various cipher *** generated many excellent results for some ciphers,for example,*** this research,we study the differential and linear propagations through the operations of addition,rotation and XOR(ARX),and construct the SAT *** apply the models to CRAX to search differential trails and linear trails *** this sense,our contnbution can be broadly divided into two *** give the bounds for differential and linear cryptanalysis of Alzette both up to 12 steps,by which we present a 3-round differential attack and a 3-round linear attack for *** construct a 4-round key-recovery attack for CRAX with time complexity289times of 4-round encryption and data complexity 225.

关键词： Ciphers Encryption Complexity theory Time complexity

SPATULA as a Versatile Tool in Plant:The Progress and Perspectives of SPATULA(SPT)Transcriptional Factor

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 517-531页

作者： lei Liang Xiangyang hu Shanghai Key Laboratory of Bio-Energy Crops Research Center for Natural ProductsPlant Science CenterSchool of Life SciencesShanghai UniversityShanghai200444China

With the rapid development of modern molecular biology and bioinformatics,many studies have proved that transcription factors play an important role in regulating the growth and development of ***(SPT)belongs to the bHLH transcription family and participates in many processes of regulating plant growth and *** review systemically summarizes the multiple roles of SPT in plant growth,development,and stress response,including seed germination,ﬂowering,leaf size,carpel development,and root elongation,which is helpful for us to better understand the functions of SPT.

关键词： SPT bHLH plant growth plant development Arabidopsis thaliana

A Privacy-preserving Energy Management System Based on Homomorphic Cryptosystem for IoT-enabled Active Distribution Network

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 167-178页

作者： Qian hu Siqi Bu Wencong su Vladimir Terzija the Department of Physics Hong Kong Baptist UniversityHong KongChina the Department of Electrical and Electronic Engineering Shenzhen Research InstituteThe Hong Kong Polytechnic UniversityHong KongChina the Department of Electrical and Computer Engineering University of Michigan-DearbornDearbornMI 48128USA the School of Engineering Newcastle UniversityNewcastleUK

Active distribution network(ADN),as a typically cyber-physical system,develops with the evolution of Internet of Things(IoTs),which makes the network vulnerable to cybersecurity *** this paper,the eavesdropping attacks that lead to privacy breaches are addressed for the IoT-enabled ADN.A privacy-preserving energy management system(EMS)is proposed and empowered by secure data exchange protocols based on the homomorphic *** the information transmission among distributed generators and load customers in the EMS,private information including power usage and electricity bidding price can be effectively protected against eavesdropping *** correctness of the final solutions,e.g.,optimal market clearing price and unified power utilization ratio,can be deterministically *** simulation results demonstrate the effectiveness and the computational efficiency of the proposed homomorphically encrypted EMS.

关键词： Eavesdropping attack energy management system homomorphic cryptosystem Internet of Things(IOTs) active distribution network(ADN) privacy-preserving

Fracture mechanism of inclusions in thick plate center under tensile loading

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Journal of Iron and Steel Research International 2024年第5期31卷 1196-1209页

作者： lei hu Li-qin Zhang Feng hu Guo-hong Zhang Kuan Zheng Collaborative Innovation Center for Advanced Steels Wuhan University of Science and TechnologyWuhan430081HubeiChina Department of Applied Physics Wuhan University of Science and TechnologyWuhan430081HubeiChina Analysis and Testing Center Wuhan University of Science and TechnologyWuhan430081HubeiChina

Segregation of solute atoms in the center of thick plates of the tempered steel can cause an inhomogeneous structural transformation and generate micron-sized inclusions,which leads to lamellar tearing of thick plate and decreases the plasticity and *** formation and fragmentation mechanisms of micron-sized inclusions,like MnS and(Nb,Ti)C,in the center of thick plates were investigated by using thermodynamic calculations,finite element simulations,and electron backscatter diffraction characterization *** results show that micron-sized inclusions nucleate and grow in the liquid phase,and under tensile loading,they exhibit three fragmentation *** local stress during the fragmentation of inclusions is lower than the critical fracture stress of adjacent grains,and phase boundaries can effectively impede crack propagation into the *** existence of a low proportion of high-angle grain boundaries(58.1%)and high Kernel average misorientation value(0.534°)in the segregation band promotes inclusions fragmentation and crack *** difference in crack initiation and propagation direction caused by the morphology of inclusions and physical properties,as well as different matrix arrest abilities,is the main reasons for the diversity of inclusion fragmentation.

关键词： Thick plate Inclusion Finite element simulation Critical fracture stress Fracture mechanism

Rational modulation of electronic structure in PtAuCuNi alloys boosts efficient electrocatalytic ethanol oxidation assisted with energy-saving hydrogen evolution

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Journal of Energy Chemistry 2024年第6期93卷 557-567,I0014页

作者： hu Yao Yinan Zheng Xin Yu Songjie hu Baolian su Xiaohui Guo Key Lab of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education The College of Chemistry and Materials ScienceNorthwest UniversityXi’an 710069ShaanxiChina Department of Inorganic Chemistry University of NamurBruxellesB-5000 NamurBelgium

Compared to conventional electrocatalytic water splitting,electrocatalytic ethanol oxidation reaction(EOR)along with hydrogen production is considered a more energy-efficient ***,we prepared a type of novel quaternary alloy catalyst(PtAuCuNi@NF)that exhibits excellent activity for EOR(0.215 V at 10 mA cm^(-2))and hydrogen evolution reaction(HER)(7 mV at 10 mA cm^(-2)).Experimental results demonstrated that both Cu and Ni modulated the electronic environment around Pt and *** electron-rich active center facilitates the rapid adsorption and dissociation of reactants and intermediates for both EOR and ***,in the ethanol-assisted overall water splitting(E-OWS),a current density of 10 mA cm^(-2)was achieved at 0.28 ***,an advanced acid-base self-powered system(A-Bsps)that can achieve a self-powered voltage of 0.59 V was ***,the self-driven hydrogen production with zero external power supply was realized by integrating A-Bsps with the E-OWS *** interesting results can provide a feasible strategy for designing and developing advanced nanoalloy-based materials for clean energy integration and use in various fields.

关键词： Pt-based alloy Electronic structure Ethanol oxidation Self-powered system Overall water splitting