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Exploration of Energy Conservation MAC Protocol of WSNs for Ubiquitous Environment

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Wuhan University Journal of Natural Sciences 2008年第4期13卷 509-512页

作者： wei wei QI Yong hou Di School of Electronic and Information Engineering Xi＇an Jiaotong University Xi＇an 710049 Shannxi China

According to analyze the facade phenomenon of wire-less sensor networks（WSNs）,this paper proposes a feasible method to state clearly and improve the power control efficiency of wire-less sensor networks（WSNs）. One of the crucial problems for WSNs is the design of medium access control （MAC） protocol. Our method want to adjust the activities of the MAC protocols control to achieve the enery conservation when the wireless communication module of sensor nodes is running, which is the major consumer of energy consumed by sensors energy. The energy efficiency of MAC protocol makes a strong impact on the network performance. To some extent,our research work describes and analyze the sources of energy consumption in MAC layer and simultaneously present an optimal method for the design of MAC protocol. Then we discusses some factors impacting on the performance of MAC protocol and metrics of performance evaluation. Eventually, the coming research direction is summarized.

关键词： wireless sensor networks (WSNs) medium accesscontrol energy conservation medium access control(MAC) protocols

XPS and PAT Study on NiAl Phase Formed in a Superalloy by Pack Cementation

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Journal of Materials Science & Technology 2006年第6期22卷 785-788页

作者： Hua wei Guichen hou Xiaofeng SUN Qi ZHENG Hengrong GUAN Zhuangqi HU Sate Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The NiAl phase prepared by pack cementation （PC） on a nickel base superalloy was investigated by X-ray photoelectron spectroscopy （XPS） and positron annihilation technique （PAT）. The focus was on the effect of the solid solution of the alloying element from substrate on the binding energy of Ni （Al） 2p peaks and vacancy concentration of the NiAI phase formed in a superalloy. The results showed that the binding energy of Ni 2p peak of the NiAI phase grown in a superalloy was shifted by up to 0.55 eV at the temperature from 850 to 1050℃ towards higher energies and the binding energy of Al 2p peak by up to 1.09 eV in comparison with the NiAl phase formed in pure Ni. The positron lifetimes obtained from the NiAl phase formed in a superalloy were found to be markedly lower than the theoretical values, indicating the decrease in vacancy concentration. The variation of binding energies and vacancy concentration are possibly due to the solid solution of the alloying atoms from the substrate into the NiAI lattice.

关键词： NiAl phase Ni-base superalloy Positron annihilation technique (PAT) X-ray photoelectron spectroscopy (XPS)

Improving cleanliness of 30Cr2Ni4MoV low-pressure rotor steel by CaO-SiO_(2)-MgO-Al_(2)O_(3) slag refining

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Journal of Iron and Steel Research International 2022年第9期29卷 1434-1445页

作者： Yong-bo Peng Cheng-song Liu Ling Yang Song-wei hou Ri-jin Cheng Hua Zhang Hong-wei Ni The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina Huangshi Product Quality Supervision and Inspection Institute Huangshi 435000HubeiChina

The optimal composition of a CaO-SiO_(2)-Al_(2)O_(3)-MgO slag in the ladle furnace refining process was investigated to precisely control the contents of[0]and[Si]and improve the cleanliness of 30Cr2Ni4MoV *** iso-[O]lines and iso-[Si] lines of the equilibrium between the CaO-SiO_(2)-Al_(2)O_(3)-MgO refining slag and 30Cr2Ni4MoV steel at 1873 K were calculated by the thermodynamic software FactSage 7.3,and the activities of SiO_(2),Al_(2)O_(3)and CaO in the refining slag were discussed to achieve the optimal composition range of the refining ***,combined with high-temperature"slag-steel"equilibrium experiments,the effects of different refining slags on the oxygen contents,chemical composi-tions,quantities and sizes of inclusions in steels were studied,and then the thermody namic formation mechanism of MgAl_(2)O_(4) inclusions in 30Cr2Ni4MoV steel was *** results showed that the contents of dissolved[O]nd[Si]in steel can be controlled below 10 × 10^(-6)and 0.05%.respectively;when the slag basicity is above *** CaO/Al_(2)O_(3)ratio is above *** the mass fraction of SiO_(2)in the slag docs not cxcced 7%.The chemical composition of the slag has a great influence on the removal and composition of *** assessed stability phase diagrams of ***_(2)O_(3)and MgOAl_(2)O_(3) inclusion formation in the Fe-Al-Mg-O system calculated by FactSage 7.3 show good agreement with the experimental results.

关键词： 30Cr2Ni4MoV steel Non metallic inclusion Refining slag Basicity CaO/Al_(2)O_(3) ratio

*** Synthesis of （Aza）indolines via Dehydrogenative [3＋2] Annulatnon： Application to Total Synthesis of （±）-Hinckdentme At

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Chinese Journal of Chemistry 2018年第10期36卷 909-915页

作者： Zhong-wei hou Hong Yan Jin-Shuai Song Hai-Chao Xu State Key Laboratory of Physical Chemistry of Solid Surfaces Key Laboratory of Chemical Biology of Fujian Province iChEM and College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China Fujian Institute of Research on Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China

An electrochemical synthesis of functionalized （aza）indolines through dehydrogenative [3＋2] annulation of arylamines with tethered alkenes has been developed. Previous reported syntheses through similar inter- and intramolecular annulation reactions required noble-metal catalysts and are mostly limited to terminal alkenes or 1,3-dienes. The electrosynthesis employs the easily available and inexpensive ferrocene as the molecular catalyst and is compatible with di-, tri- and even tetrasubstituted alkenes to construct indolines as well as the more challenging azaindolines. Employing the newly developed electrosynthesis as a key step, the total synthesis of marine alkaloid （＋）-hinckdentine A has been achieved in 12 steps （longest linear sequence） from commercially available materials.

关键词： electrochemistry indoline radical annulation hinckdentine A

Advances in electrical impedance tomography-based brain imaging

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Military Medical Research 2022年第6期9卷 705-726页

作者： Xi-Yang Ke wei hou Qi Huang Xue hou Xue-Ying Bao wei-Xuan Kong Cheng-Xiang Li Yu-Qi Qiu Si-Yi Hu Li-Hua Dong Department of Radiation Oncology and Therapy the First Hospital of Jilin UniversityChangchun 130021China Jilin Provincial Key Laboratory of Radiation Oncology and Therapy the First Hospital of Jilin UniversityChangchun 130021China NHC Key Laboratory of Radiobiology School of Public HealthJilin UniversityChangchun 130021China CAS Key Laboratory of Bio-Medical Diagnostics Suzhou Institute of Biomedical Engineering and TechnologyChinese Academy of SciencesSuzhou 215163JiangsuChina

Novel advances in the field of brain imaging have enabled the unprecedented clinical application of various imaging modalities to facilitate disease diagnosis and treatment. Electrical impedance tomography(EIT) is a functional imaging technique that measures the transfer impedances between electrodes on the body surface to estimate the spatial distribution of electrical properties of tissues. EIT offers many advantages over other neuroimaging technologies,which has led to its potential clinical use. This qualitative review provides an overview of the basic principles,algorithms, and system composition of EIT. Recent advances in the field of EIT are discussed in the context of epilepsy,stroke, brain injuries and edema, and other brain diseases. Further, we summarize factors limiting the development of brain EIT and highlight prospects for the field. In epilepsy imaging, there have been advances in EIT imaging depth,from cortical to subcortical regions. In stroke research, a bedside EIT stroke monitoring system has been developed for clinical practice, and data support the role of EIT in multi-modal imaging for diagnosing stroke. Additionally, EIT has been applied to monitor the changes in brain water content associated with cerebral edema, enabling the early identification of brain edema and the evaluation of mannitol dehydration. However, anatomically realistic geometry,inhomogeneity, cranium completeness, anisotropy and skull type, etc., must be considered to improve the accuracy of EIT modeling. Thus, the further establishment of EIT as a mature and routine diagnostic technique will necessitate the accumulation of more supporting evidence.

关键词： Electrical impedance tomography(EIT) Brain diseases Tissue impedance Microelectrode array

Spatiotemporal dynamics of population density in China using nighttime light and geographic weighted regression method

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International Journal of Digital Earth 2023年第1期16卷 2704-2723页

作者： wei Guo Jinke Liu Xuesheng Zhao wei hou Yunxuan Zhao Yongxing Li Wenbin Sun Deqin Fan College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijingPeople’s Republic of China Chinese Academy of Surveying&Mapping BeijingPeople’s Republic of China

The distribution and dynamic changes of regional or national population data with long time series are very important for regional planning,resource allocation,government decision-making,disaster assessment,ecological protection,and other sustainability ***,the existing population datasets such as LandScan and WorldPop all provide data from 2000 with limited time series,while GHS-POP only utilizes land use data with limited *** view of the limited remote sensing images of long time series,it is necessary to combine existing multi-source remote sensing data for population spatialization *** this research,we developed a nighttime light desaturation index(NTLDI).Through the cross-sensor calibration model based on an autoencoder convolutional neural network,the NTLDl was calibrated with the same period Visible Infrared Imaging Radiometer Suite Day/Night Band(VIRS-DNB)***,the geographically weighted regression method is used to determine the population density of China from 1990 to 2020 based on the long time series ***,the change characteristics and the driving factors of China's population spatial distribution are *** large-scale,long-term population spatialization results obtained in this study are of great significance in government planning and decision-making,disaster assessment,resource allocation,and other aspects.

关键词： Nighttime light Population density Geographically weighted regression Population spatialization Driving force analysis

Experimental research on the performance of PSA and other fiber filter

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Experimental research on the performance of PSA and other fi...

Evolution of chemistry and selection technology for DNA-encoded library

第八届中国功能材料及其应用学术会议

作者： MA Cheng-yu hou wei-li LIN Yong State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry School of Environmental Science and EngineeringDonghua University

ISBN: (纸本)9783037859698

The paper presents the comparative test among the high temperature resistant filter(such as PSA fiber,PMIA fiber,PI fiber) of the bag filter about their heat resistance and the corrosion *** research test the breaking strength,the breaking elongation and the molecular structure of those *** show that the breaking strength of the PSA increase slightly under the high temperature up to250℃,while the breaking strength of the PMIA fiber decrease 75.26%and the breaking strength of PI fiber decrease 65.57%.After being soaked in the sulfuric acid solution for 96 hours,the strength retentions of PSA,PMIA-1 and PMIA-2 are 42%,18.85%and46.71%.The result of testing by FTIR shows that the amide bond of the PSA fiber fracture and generate phenolics and carboxylic acid after the chemical treatment,which is the main reason why the fiber strength of PSA decrease after the acid and alkaline corrosion.

关键词： PSA fiber PMIA fiber PI fiber Heat resistance The corrosion resistance Breaking strength The strength retentions FTIR

来源： cnki会议评论

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Acta Pharmaceutica Sinica B 2024年第2期14卷 492-516页

作者： Peixiang Ma Shuning Zhang Qianping Huang Yuang Gu Zhi Zhou wei hou wei Yi Hongtao Xu Shanghai Key Laboratory of Orthopedic Implants Department of OrthopedicsShanghai Ninth People’s HospitalShanghai Jiao Tong UniversitySchool of MedicineShanghai 200025China Shanghai Institute for Advanced Immunochemical Studies ShanghaiTech UniversityShanghai 201210China Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target&Clinical Pharmacology The NMPA and State Key Laboratory of Respiratory DiseaseGuangzhou Medical UniversityGuangzhou 511436China College of Pharmaceutical Science and Institute of Drug Development&Chemical Biology Zhejiang University of TechnologyHangzhou 310014China

DNA-encoded chemical library(DEL)links the power of amplifiable genetics and the nonself-replicating chemical phenotypes,generating a diverse chemical *** analogy with the biological world,the DEL world can evolve by using a chemical central dogma,wherein DNA replicates using the PCR reactions to amplify the genetic codes,DNA sequencing transcripts the genetic information,and DNA-compatible synthesis translates into chemical ***,DNA-compatible synthesis is the key to expanding the DEL chemical ***,the evolution-driven selection system pushes the chemicals to evolve under the selective pressure,i.e.,desired selection *** this perspective,we summarized recent advances in expanding DEL synthetic toolbox and panning strategies,which will shed light on the drug discovery harnessing in vitro evolution of chemicals via DEL.

关键词： DNA-encoded library Drug discovery High-throughput selection DNA-compatible synthesis In vitro evolution Chemical central dogma

Static dielectric constant and dielectric loss of cellulose insulation:Molecular dynamics simulations

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High Voltage 2021年第6期6卷 1051-1060页

作者： wei hou Lijun Yang Yang Mo Fei Yin Youyu Huang Xiaoling Zheng State Key Laboratory of Power Transmission Equipment and System Security and New Technology Chongqing UniversityChongqingChina Hunan Guangxin Technology Co LtdShaoyangHunanChina

Reducing the dielectric constant and loss of cellulose insulation can make the electric field distribution uniform in oil‐paper insulation systems and decrease the heat generation in dielectric materials,thus ensuring a reliable transformer *** guide the experimental design from the molecular level,the fluctuation method was introduced into the molecular dynamics simulation to evaluate the static permittivity of cellulose insulation,ε*** correlation between the dynamics parameter mean square displacement(MSD)and dielectric loss induced by orientational polarization,was *** simulation results and experimental values of five types of cellulose insulation were compared to verify the rationality of the proposed *** results indicated that the simulation values ofεs for five models were agreed well with the experimental values in terms of both the magnitude and the variation *** simulation time and permittivity of the surrounding mediumεRF are two key parameters,which determine the accuracy of the simulation results ofε*** the convergence,15 ns was chosen as the lower limit of simulation *** reaction field approximation was adopted to calculate the dipole‐dipole interaction instead of true interaction,that is,εRF→∞.The MSD results reproduced the experimental trend in dielectric loss,indicating that the method can qualitatively predict the dielectric loss of cellulose ***,these methods are sufficient to guide design experiments and provide a route to understand the mechanism of the change in dielectric properties at the molecular level.

关键词： dielectric insulation dynamics