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Swelling pressure evolution characterization of strong expansive soil considering the influence of reserved expansion deformation

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Journal of Mountain Science 2024年第1期21卷 252-270页

作者： LI Tianguo kong Lingwei GUO Aiguo YAN Junbiao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China university of Chinese Academy of Sciences Beijing 100049China

Numerous engineering cases have demonstrated that the expansive soil channel slope remains susceptible to damage with the implementation of a rigid or closed protective structure. It is common for the protective structure to experience bulging failure due to excessive swelling pressure. To investigate the swelling pressure properties of expansive soil, the constant volume test was employed to study the influence of water content and reserved expansion deformation on the characteristics of swelling pressure in strong expansive soils, and also to explore the evolution mechanism of the swelling pressure. The findings demonstrate that the swelling pressure-time curve can be classified into swelling pressure-time softening and swelling pressure-time stability type. The swelling pressuretime curve of the specimen with low water content is the swelling pressure-time softening type, and the softening level will be weakened with increasing reserved expansion deformation. Besides, the maximum swelling pressure Psmax decreases with increasing water content and reserved expansion deformation, especially for expansion ratio η from 2.% to 37%. The reserved deformation has little effect on reducing Psmax when it is beyond 7% of the expansion rate. The specimen with low water content has a more homogeneous structure due to the significant expansion-filling effect, and the fracture and reorganization of the aggregates in the specimens with low water content cause the swelling pressure-time softening behavior. In addition, the proposed swelling pressure-time curve prediction model has a good prediction on the test results. If necessary, a deformation space of about 7% expansion rate is recommended to be reserved in the engineering to reduce the swelling pressure except for keeping a stable water content.

关键词： Expansive soil Swelling pressure Reserved expansion deformation Water content

Sedimentary Characteristics,Ages,and Environmental Significance of Gravel Deposits and Loess in Shandong,Eastern china:Regional Response to Global Change Since the Last Glacial Period

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 491-504页

作者： WANG Min kong Fanbiao kong Xianglun CHEN Haitao WANG Jiawei MIAO Xiaodong JIA Guangju HAN Mei XU Shujian Department of Geography and Tourism Qilu Normal UniversityJinan 250014China School of Geography and Environment Shandong Normal UniversityJinan 250014China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection Linyi UniversitySchool of Resources and EnvironmentLinyiShandong 276005China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China

Investigation of rarely studied gravel layers found in the loess in Shandong Province,eastern china,reveals the fabric characteristics of two gravel layers(G1,G2.and the sedimentary characteristics of loess at the typical and well-preserved Heiyu section(HY),where,to determine the paleoclimatic changes during Marine Isotope Stage *** stimulated luminescence dates of the HY formation range from 0.2.±0.02.ka to 39.00±2.00 *** addition,the ages of G1 and G2.were estimated using the Bayesian model to be 39.60-40.50 and 2..00-2..50 ka.G1 and G2.are mainly composed of fine and medium gravel,both of which were subangular to subrounded limestone,with gravel directions to NE and *** average flow velocity,average depth,and flood peak flow of G1 are 1.10 m/s,0.49 m,and 37.04 m^(3)/s,respectively,calculated using the flow energy method,whereas those of G2.are 0.98 m/s,0.38 m,and 18.38 m^(3)/s,*** of climate proxy indices show that the sedimentary environment of the gravel and loess in HY might be a regional response to global change.

关键词： paleoenvironment geochronology gravel layer sedimentology Pleistocene Shandong Province

Deformation and stability of the seawall,considering the strength uncertainty of cement mixing piles

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2024年第6期25卷 483-501页

作者： Yuansheng YU Lingling LI Xiangmiao kong Chengyuan LI Zhen GUO Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Hainan Institute Zhejiang UniversitySanya572000China Ninghai Highway and Transportation Management Center Ningbo315600China Ninghai Traffic Engineering Construction Management Institute Ningbo315600China

The cement mixing (CM) pile is a common method of improving soft offshore ground. The strength growth of CM piles under complex conditions is affected by many factors, especially the cement and moisture contents, and shows significant uncertainty. To investigate the stochasticity of the early strength of CM piles and its impact on the displacement and stability of a seawall, a series of laboratory tests and numerical analyses were carried out in this study. Vane shear tests were conducted on the cement-solidified soil to determine the relationships between the undrained shear strength s_(u) of the cement soil curing in the seawater and the cement content a_(c), as well as the in situ soil moisture content w. It can be inferred that the 2. h undrained shear strength follows a normal distribution. A numerical model considering the random CM pile strength was established to investigate the deformation of the seawall. Due to the uncertainty of CM pile strength, the displacement of the seawall demonstrates a certain discreteness. The decrease of the mean undrained shear strength of CM piles causes a corresponding increase in the average displacement of the seawall. When the mean strength of CM piles is lower than a certain threshold, there is a risk of instability. Furthermore, the heterogeneity of the strength within an individual CM pile also has an impact on seawall displacement. Attention should be paid to the uncertainty of CM pile strength to control displacement and stability.

关键词： Construction uncertainty Cement mixing(CM)pile Strength of cement soil Seawall stability Random finite element method(RFEM) Monte Carlo simulation(MCS)

Inhibition of SLC2.A4 regulated by electroacupuncture suppresses the progression of myocardial ischemia-reperfusion injury

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BIOCELL 2024年第4期48卷 665-675页

作者： FEI kong QIYUAN TIAN BINGLIN KUANG LILI SHANG XIAOXIAO ZHANG DONGYANG LI YING kong Department of Endocrinology Heilongjiang University of Chinese MedicineHarbin150040China Department of Cardiology Heilongjiang University of Chinese MedicineHarbin150040China College of Clinical Medicine Heilongjiang University of Chinese MedicineHarbin150040China Department of Nephrology Beijing Hospital of Integrated Traditional Chinese and Western MedicineBeijing100039China College of Acupuncture and Massage Heilongjiang University of Chinese MedicineHarbin150040China Department of Acupuncture Heilongjiang University of Chinese MedicineHarbin150040China

Introduction:Myocardial ischemia-reperfusion(IR)injury has received widespread attention due to its damaging ***(EA)pretreatment has preventive effects on myocardial IR ***2.A4 is a Na+independent anion reverse transporter and has not been reported in myocardial IR ***:Toﬁnd potential genes that may be regulated by EA and explore the role of this gene in myocardial IR ***:RNA sequencing and bioinformatics analysis were performed to obtain the differentially expressed genes in the myocardial tissue of IR rats with EA *** infarction size was detected by TTC *** CK,creatinine kinase-myocardial band,Cardiac troponin I,and lactate dehydrogenase levels were determined by *** effect of SLC2.A4 on cardiomyocyte apoptosis was explored by TUNEL staining and western *** effects of SLC2.A4 on inﬂammation were determined by HE staining,ELISA,and real-time *** effect of SLC2.A4 on the NF-κB pathway was determined by western ***:SLC2.A4 was up-regulated in IR rats but downregulated in IR rats with EA *** with IR rats,those with SLC2.A4 knockdown exhibited improved cardiac function according to decreased myocardial infarction size,reduced serum LDH/CK/CK-MB/cTnI levels,and elevated left ventricular ejection fraction and fractional ***2.A4 silencing inhibited myocardial inﬂammation,cell apoptosis,phosphorylation,and nuclear translocation of NF-κB ***:SLC2.A4 exhibited promoting effects on myocardial IR injury,while the SLC2.A4 knockdown had an inhibitory effect on the NF-κB *** results further unveil the role of SLC2.A4 in IR injury.

关键词： Myocardial ischemia Reperfusion SLC2.A4 NF-κB pathway

Corrosion of Duplex Stainless Steel Manufactured by Laser Powder Bed Fusion: A Critical Review

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 587-606页

作者： Yiqi Zhou Decheng kong Ruixue Li Xing He Chaofang Dong Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing100083China Shanghai Key Laboratory of Advanced High-Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China

Laser powder bed fusion (LPBF) is a commonly used additive manufacturing (AM) method for efficiently producing intricate geometric components. This investigation examines factors such as pores, cellular structure, grain size, and inclusions from the manufacturing process that contribute to the corrosion resistance of LPBF DSS. Furthermore, the as-built LPBF duplex stainless steel (DSS) is primarily ferrite due to the rapid cooling process. Therefore, the transformation of ferrite to austenite after various heat treatments in LPBF DSS and its corresponding corrosion resistance are presented. Additionally, a new mixed powder method is proposed to increase the austenite content in the as-built LPBF DSS. This review also focuses on the passivation capability and pitting corrosion performance in LPBF and conventional DSS. This article summarizes the variations in microstructure between as-built and heat-treated LPBF DSS, with their impacts on corrosion resistance, offering insights for manufacturing highly corrosion-resistant LPBF DSS.

关键词： Laser powder bed fusion Duplex stainless steel Microstructure Heat treatment Passivation Pitting corrosion

Kinematic calibration method with high measurement efficiency and robust identification for hybrid machine tools

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Chinese Journal of Aeronautics 2024年第3期37卷 468-482页

作者： Liping WANG Mengyu LI Guang YU Weitao LI Xiangyu kong State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Precision/Ultra-precision Manufacturing Equipment and Control Beijing 100084China

Geometric error is the main factor affecting the machining accuracy of hybrid machine *** calibration is an effective way to improve the geometric accuracy of hybrid machine *** necessity to measure both position and orientation at each pose,as well as the instability of identification in case of incomplete measurements,severely affects the application of traditional calibration *** this study,a kinematic calibration method with high measurement efficiency and robust identification is proposed to improve the kinematic accuracy of a five-axis hybrid machine ***,the configuration is introduced,and an error model is ***,by investigating the mechanism error characteristics,a measurement scheme that only requires tool centre point position error measurement and one alignment operation is ***,by analysing the effects of unmeasured degrees of freedom(DOFs)on other DOFs,an improved nonlinear least squares method based on virtual measurement values is proposed to achieve stable parameter identification in case of incomplete measurement,without introducing additional ***,the proposed calibration method is verified through simulations and *** proposed method can efficiently accomplish the kinematic calibration of the hybrid machine *** accuracy of the hybrid machine tool is significantly improved after calibration,satisfying actual aerospace machining requirements.

关键词： Hybrid machine tool Calibration Measurement scheme Improved nonlinear least squares method Virtual measurement values

Hydrodynamics and OCM reaction performance in a bubbling fluidized bed reactor and a riser reactor

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Particuology 2024年第3期86卷 188-204页

作者： Min Cai Shuangzhu kong Sheng Chen Mengxi Liu Chunxi Lu State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China china Special Equipment Inspection and Research Institute Beijing102249China

The reasonable reactor design is of great importance for increasing the C_(2. yield(C2.4 and C2.6)of the oxidative coupling of methane(OCM),and the OCM reactor should remove the heat released in reactions quickly and efficiently and minimize the consecutive reaction of ethylene to carbon *** fluidized bed reactor is characterized by excellent heat transfer,superior mass transport,and large handling capacity,while fewer studies focused on large-scale fluidized bed reactors for the OCM ***,large cold-model experiments and computational fluid dynamics simulations were conducted to investigate hydrodynamics and the OCM reaction performance in a large-scale bubbling fluidized bed(BFB)and a large-scale *** the BFB reactor,consecutive reactions of ethylene are acute because of the strong gas back-mixing,high solids holdup,and non-uniform solids *** the consecutive reactions of ethylene are negligible due to the plug flow structure and low solids holdup in the riser ***,both reactors can achieve isothermal operation for the OCM *** C_(2. selectivity of 45.4% and C_(2. yield of 2..1% are obtained in the riser reactor,increasing by 2..3% and 5.8% individually than that in the BFB *** study provides useful information and reference to the OCM reactor designandcommercialization.

关键词： Oxidative coupling of methane Bubbling fluidized bed reactor Riser reactor Hydrodynamics Isothermal operation

Inhibition effect of sulfation on Pt/TiO_(2. catalysts in methane combustion

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Chinese Journal of Structural Chemistry 2024年第5期43卷 18-21页

作者： Fanxin kong hongzhi Wang Huimei Duan School of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textilesInstitute of Marine Biobased MaterialsQingdao UniversityQingdao266071China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao266100China

Methane as an attractive clean energy is a strong greenhouse gas with the global warming potential 86 times higher than that of CO_(2.over 2. years[1].Hence,the removal of unburned methane emitted from natural gas application processes is a serious environmental ***,methane is a geometrically high-symmetric and nonpolar molecule with high C-H bond energy(439 kJ mol^(-1))and low electron affinity(4.4 eV),rendering it extremely difficult to be activated under mild conditions[2..

关键词： methane rendering attractive

A GAN-EfficientNet-Based Traceability Method for Malicious Code Variant Families

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Computers, Materials & Continua 2024年第7期80卷 801-818页

作者： Li Li Qing Zhang Youran kong School of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

Due to the diversity and unpredictability of changes in malicious code,studying the traceability of variant families remains *** this paper,we propose a GAN-EfficientNetV2.based method for tracing families of malicious code *** method leverages the similarity in layouts and textures between images of malicious code variants from the same source and their original family of malicious code *** method includes a lightweight classifier and a *** classifier utilizes the enhanced EfficientNetV2.to categorize malicious code images and can be easily deployed on mobile,embedded,and other *** simulator utilizes an enhanced generative adversarial network to simulate different variants of malicious code and generates datasets to validate the model’s *** process helps identify model vulnerabilities and security risks,facilitating model enhancement and *** classifier achieves 98.61%and 97.59%accuracy on the MMCC dataset and Malevis dataset,*** simulator’s generated image of malicious code variants has an FID value of 155.44 and an IS value of 1.72.*** classifier’s accuracy for tracing the family of malicious code variants is as high as 90.2.%,surpassing that of mainstream neural network *** meets the current demand for high generalization and anti-obfuscation abilities in malicious code classification models due to the rapid evolution of malicious code.

关键词： Malicious code variant traceability feature reuse lightweight neural networks code visualization attention mechanism