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Shear Strength and Dilatancy of Calcareous Sand in the South China Sea

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China Ocean Engineering 2022年第5期36卷 781-790页

作者： PEI hui-min WANG dong Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Qingdao National Laboratory for Marine Science and Technology Qingdao 266100China

The shear strength and dilatancy of typical uncemented calcareous sand from the South China Sea are investigated by soil lab tests.According to drained triaxial tests at various relative densities and confining stresses,it is found that the constant volume friction angle is approximated as 39°and the traditional Bolton’s equations can be modified to estimate the peak friction angle and dilation angle.The reliability of the equation proposed for the peak friction angle is verified in terms of calcareous sands from more onshore and offshore sites worldwide,while the errors of the predicted dilation angles scatter in a relatively large range.Totally,the dilation angles of sands in the South China Sea are estimated by the equation presented with an error of±30%.The peak friction angle measured by the undrained is similar to that by the drained tests as the relative density smaller than 60%,while the former is slightly lower for denser samples.

关键词： calcareous sand triaxial tests friction angle dilatancy drained South China Sea

Coptidis Rhizoma-Contained Traditional Formulae for Insomnia:A Potential to Prevent Diabetes?

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Chinese Journal of Integrative Medicine 2018年第10期24卷 785-788页

作者： HUANG Wen-ya DONG Hui Institute of Integrative Traditional Chinese and Western Medicine Tongji Hospital Tongji Medical College Huazhong University of Science and Technology

It has been well known that insomnia and sleep deprivation can lead to many metabolic diseases such as type 2 diabete mellitus （T2DM）o Chinese medicine （CM） has been used to improve insomnia and showed many good therapeutic effects. Some Coptidis Rhizoma-contained traditional formulae have been found to exert obvious effects on insomnia, such as Jiaotai Pill （交泰丸）, Huanglian Ejiao Decoction （黄连阿胶汤）, Huanglian Wendan Decoction （黄连温胆汤）, Niuhuang Qingxin Pill （牛黄清心丸）, and Zhusha Anshen Pill （朱砂安神丸）. Coptidis Rhizoma, a traditional herbal medicine which can purge Xin （Heart） fire, is the most important component of these formulas. Studies have found that these formulae could improve T2DM symptoms. We hypothesized that treating insomnia theoretically may help to prevent diabetes and organized many experimental studies in this review and concluded that Coptidis Rhizoma-contained traditional formulae for insomnia might be a potential to prevent diabetes.

关键词： Chinese medicine Coptidis Rhizoma herbal formulae insomnia diabetes

WBZUC:novel white-box ZUC-128 stream cipher

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The Journal of China Universities of Posts and Telecommunications 2023年第2期30卷 96-106页

作者： Yang Yatao Zhang Ruoqing DONG Hui Ma Yingjie Zhang Xiaowei Department of Electronic and Communication Engineering Beijing Electronic Science and Technology InstituteBeijing 100070China School of Telecommunication Engineering Xidian UniversityXi'an 710071China Hong Kong Applied Science and Technology Research Institute Hong Kong 999077China

White-box cryptography is critical in a communication system to protect the secret key from being disclosed in a cryptographic algorithm code implementation.The stream cipher is a main dataflow encryption approach in mobile communication.However,research work on white-box cryptographic implementation for stream cipher is rare.A new white-box Zu Chongzhi-128(ZUC-128)cryptographic implementation algorithm named WBZUC was proposed.WBZUC adopts lookup table and random coding in the non-linear function to make the intermediate value chaotic without changing the final encryption result.Thus,the WBZUC algorithm’s security gets improved compared with the original ZUC-128 algorithm.As for the efficiency,a test experiment on WBZUC shows that the average speed of key generation,encryption,and decryption can reach at 33.74 kbit/s,23.31 kbit/s,24.06 kbit/s respectively.Despite its running speed is relatively a bit lower than original ZUC-128 algorithm,WBZUC can provide better security and comprehensive performance in mobile communication system environment.

关键词： Zu Chongzhi-128(ZUC-128)algorithm white-box cryptography cryptographic implementation lookup table secure communication

Effects of geosorbent and solution properties on sorption and desorption of PAHs

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Acta Geochimica 2021年第2期40卷 212-224页

作者： hui dong Baohua Xiao State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550018China University of Chinese Academy of Sciences Beijing 100049China

Characteristics of phenanthrene and pyrene’s sorption and desorption on two local soils in solutions of simulated groundwater,simulated lung fluid,and simulated saliva were studied with batch equilibrium experiments to understand the fate of PAHs in the karst region of southwestern China and to assess the environmental exposure and the health risk of PAHs.The results showed that the sorption and desorption isotherms of phenanthrene and pyrene on two target soils in the three solution systems could be adequately described by the Freundlich model,while the fitted isotherm parameters for the simulated groundwater solution distinguished notably from those for the simulated body fluid solutions.For the sorption experiments,in the simulated groundwater,the n values were 0.722 and 0.672 for phenanthrene and were 0.724 and0.663 for pyrene,respectively,on the yellow soil and the limestone soil;The log KF values were 3.118 and 3.323 for phenanthrene and were 3.648 and 3.846 for pyrene,respectively,on the yellow soil and the limestone soil.In the simulated body fluids,the n values for phenanthrene and pyrene ranged from 0.622 to 0.836 and from 0.590 to0.865,respectively,and the log KF values of phenanthrene and pyrene ranged from 2.845 to 3.327 and from 3.344 to3.779,respectively.For the desorption experiments,in the simulated groundwater,the n values were 0.662 and 0.744 for phenanthrene and were 0.702 and 0.647 for pyrene,respectively,on the yellow soil and the limestone soil.The log KF values were 3.666 and 3.686 for phenanthrene and were 4.128 and 4.225 for pyrene,respectively,on the yellow soil and the limestone soil.In the simulated body fluids,the n values for phenanthrene and pyrene ranged from 0.612 to 0.668 and from 0.631 to 0.819,respectively,and the log KF values of phenanthrene and pyrene ranged from 3.134 to 3.407 and from 3.533 to 3.839,respectively.The limestone soil had relatively higher log KF values but lower KOC values compared to those of the yellow soil,indicated that the nature of sorbent soils played

关键词： PAHs Sorption–desorption Simulated body fluids Yellow soil Limestone soil

Tactics to optimize conversion-type metal fluoride/sulfide/oxide cathodes toward advanced lithium metal batteries

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Nano Research 2023年第6期16卷 8173-8190页

作者： dong Yan hui Ying Yang Ying Bai International Joint Laboratory of New Energy Materials and Devices of Henan Province School of Physics&ElectronicsHenan UniversityKaifeng 475004China Pillar of Engineering Product Development Singapore University of Technology and DesignSingapore 487372Singapore

Considering limited energy density of current lithium metal batteries(LMBs)due to low capacity of traditional intercalation-type cathodes,alternative high-energy cathodes are eagerly demanded.In this regard,conversion-type metal fluoride/sulfide/oxide cathodes have emerged great attention owing to their high theoretical specific capacities,supplying outstanding energy density for advanced LMBs.However,their low ionic/electrical conductivities,huge volume changes,sluggish reaction kinetics,and severe side reactions result in quick capacity fading and poor rate capability of LMBs.Recent research efforts on the conversiontype cathodes have brought new insights,as well as effective approaches toward realizing their excellent electrochemical performances.Here,the recent discoveries,challenges,and optimizing strategies including morphology regulation,phase structure engineering,surface coating,heterostructure construction,binder functionalization,and electrolyte design,are reviewed in detail.Finally,perspectives on the conversion-type metal fluoride/sulfide/oxide cathodes in LMBs are provided.It is believed that the conversion-type cathodes hold a promising future for the next-generation LMBs with high energy density.

关键词： conversion-type cathodes electrochemical performances optimizing strategies lithium metal batteries

Development of fuelling protocols for gaseous hydrogen vehicles:a key component for efficient and safe hydrogen mobility infrastructures

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Clean Energy 2023年第1期7卷 23-29页

作者： Zhuang Xu Wenping dong Yuejing Zhao hui dong Guangli He National Institute of Clean-and-Low-Carbon Energy Beijing102211P.R.China

Large-scale applications of fuel-cell vehicles(FCVs)are of vital importance to reduce emissions of greenhouse gases in the transportation sector,especially in the heavy-duty and long-distance scenarios.Efficient fuelling for the on-board gaseous hydrogen cylinders of an FCV is essential to achieve a fuelling experience that is comparable to that of traditional fossil-fuel-powered vehicles.However,the heating effect during refuelling leads to potential safety issues when the hydrogen temperature in the cylinder exceeds 85℃.Therefore,fuelling protocols are critical to ensure the efficiency and safety of the hydrogen mobility infrastructure.In this paper,the fuelling protocols for FCV vans and buses with type III cylinders were developed and the pre-cooling temperatures were optimized to minimize the energy consumption.Their performance was demonstrated with a 35-MPa hydrogen fuelling station.We found that FCV vans and buses can be safely refuelled in 3 or 5 minutes at a minimum,respectively,demonstrating a fuelling experience that is similar to that of traditional vehicles.

关键词： hydrogen refuelling station fuelling protocols fuel-cell vehicle hydrogen temperature

Compression behavior of metal foams with real pore structures through CT scan images

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Journal of Iron and Steel Research(International) 2022年第11期29卷 1886-1897页

作者： Lei Wang Kai Jiang dong-hui Yang College of Mechanics and Materials Hohai UniversityNanjing 211100JiangsuChina Suqian Research Institute of Hohai University Suqian 223814JiangsuChina

Based on the real pore structure obtained from computed tomography(CT)scan images,a three-dimensional(3D)model of the metal foam sample with specified porosity is established,and the model is compressed and simulated by finite element method with the simulation results compared with the experimental test results for validation.At the same time,based on the spatial distribution characteristics of cells extracted from 3D model construction,a widely used metal foam model with Voronoi pore structure or spherical pore structure was established and simulated under compression.The two compression simulation results with regular pore structure models were also compared with the experimental results and CT model results to study the influence of cell wall morphology on the compression performance of metal foams.The simulation results show that CT model agrees well with the experimental results and is more accurate than Voronoi pore or spherical pore model,which can provide a more reasonable option for investigation of metal foams.

关键词： Metal foam Computed tomography scan Three-dimensional reconstruction Cell wall morphology Compression performance

High-speed train positioning based on a combination of Beidou navigation, inertial navigation and an electronic map

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Science China(Information Sciences) 2023年第7期66卷 237-252页

作者： hui YANG Shuai-Qiang dong Chun-Hua XIE School of Electrical and Automation Engineering East China Jiaotong University Key Laboratory of Advanced Control & Optimization of Jiangxi Province East China Jiaotong University State Key Laboratory of Performance Monitoring Protecting of Rail Transit Infrastructure East China Jiaotong University

To date, the studies on the combination positioning of high-speed trains have made great progress, but the positioning accuracy of these methods is relatively low. Map-matching positioning can improve positioning accuracy, but information transmission is time-consuming. Few studies incorporate it into combination positioning. To solve the problem, this paper proposes a high-speed train positioning method based on combining a Beidou navigation system, an inertial navigation system, and an electronic map. First, the combination positioning problem is transformed into a multi-objective optimization problem, which weights the direction similarity and distance error to form a fitness function and converts the railway line and the maximum error range of each positioning system into constraints. Second, an improved differential evolution algorithm is proposed to solve this problem. By referencing the gray wolf algorithm,the differential evolution algorithm updates individuals by varying toward the direction of multiple optimal values. Then, a new combination positioning algorithm for high-speed trains is proposed. In the simulation,the increase in positioning speed and accuracy is analyzed and validated. Compared to the current algorithms, the proposed algorithm performs better. The proposed method has practical value for improving the reliability and safety of train operations.

关键词： electronic map multi-objective optimization differential evolution algorithm Beidou navigation system high-speed train positioning

Total Synthesis of Syringin and Its Natural Analogues via C—C Bond Activation of Aryl Ketones

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Chinese Journal of Chemistry 2023年第24期41卷 3587-3592页

作者： Zhen-Yu Wang Yi Sun Guo-dong Sun hui Xu hui-Xiong Dai School of Chinese Materia Medica Nanjing University of Chinese MedicineNanjingJiangsu210023 China CAS Key Laboratory of Receptor Research State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203 China University of Chinese Academy of Sciences Beijing100049 China

Syringin is found in the root of Acanthopanax senticosus(Rupr.Maxim.)Harms and belongs to the lignin chemical compound with many biological activities.In this study,we employed commercially available starting materials and accomplished the total synthesis of syringin in 5 steps with an overall yield of 58%.Palladium-catalyzed C(O)–C bond activation and subsequent cross coupling reaction is the key to construct syringin and its natural analogues.

关键词： Syringin Total synthesis Cross-coupling C—C activation Syringin analogues