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Comparative Assessment on Microstructure and Properties of in-situ TiC+Ti_(5)Si_(3)Reinforced TiAl-Sn-Zr Matrix Composites by Spark Plasma Sintering and Argon Protected Sintering

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Journal of Wuhan University of Technology(Materials Science) 2023年第1期38卷 199-205页

作者：姚辉许晓静 CAI chengbin LI Chen CHEN Fenghua LIU Yangguang xiao Yishui Institute for Advanced Manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang 212013China

The effects of SiC particles(SiCp)on high temperature oxidation behavior of titanium matrix composites(TMCs)under different powder metallurgy processes were investigated.In situ Ti C+Ti_(5)Si_(3)reinforced titanium matrix composites were prepared by discharge plasma sintering(SPS)and argon protective sintering(APS).The results show that the two processes have a negligible effect on the composition and hardness of the samples,but the hardness of the two samples is significantly improved by adding SiCp.The apparent porosity of SPS process is obviously smaller than that of APS process,whereas,the apparent porosity increases slightly with the addition of SiCp.The oxide layer thickness and mass gain of the samples obtained by SPS process are smaller than those obtained by APS process.The oxide thickness and mass gain of both processes are further reduced by adding SiCp.The SPS composites showed the best high temperature oxidation resistance.Therefore,TMCs with Si Cp by SPS can effectively improve the high-temperature oxidation behavior of the materials.

关键词： powder metallurgy titanium matrix composites High-temperature oxidation TiC and Ti_(5)Si_(3) Ti-Al-Sn-Zr

Effects of nicotinamide and riboflavin on the biodesulfurization activity of dibenzothiophene by Rhodococcus erythropolis USTB-03

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Journal of Environmental Sciences 2008年第5期20卷 613-618页

作者： YAN Hai SUN Xudong XU Qianqian MA Zhao XIAO Chengbin Ning Jun Department of Biological Science and Technology School of Applied Science University of Science and Technology Beijing Beijing 100083 China Research Center for Eco-environmental Science Chinese Academy of Sciences Beijing 100085 China

Rhodococcus erythropolis USTB-03 is a promising bacterial strain for the biodesulfurization of dibenzothiophene （DBT） via a sulfurspecific pathway in which DBT is converted to 2-hydroxybiphenyl （2HBP） as an end product. The effects of nicotinamide and riboflavin on the sulfur specific activity （SA） of DBT biodesulfurization by R. erythropolis USTB-03 were investigated. Both nicotinamide and riboflavin were found to enhance the expression of SA, which was not previously reported. When R. erythropolis USTB-03 was grown on a medium containing nicotinamide of 10.0 mmol or riboflavin of 50.0 μmol, SA was raised from 68.0 or so to more than 130 mmol 2HBP/（kg dry cells.h）. When R. erythropolis USTB-03 was grown in the presence of both nicotinamide of 5.0 mmol and riboflavin of 25.0 μmol, SA was further increased to 159.0 mmol 2HBP/（kg dry cells.h）. It is suggested that the biological synthesis of reduced form of flavin mononucleotide （FMNH2）, an essential coenzyme for the activities of biodesulfurization enzyme Dsz C and A, might be enhanced by nicotinamide and riboflavin, which was responsible for the increased SA of R. erythropolis USTB-03.

关键词： biodesulfurization dibenzothiophene nicotinamide Rhodococcus erythropolis USTB-03 riboflavin

Nitrate transporter NRT1.1 and anion channel SLAH3 form a functional unit to regulate nitrate-dependent alleviation of ammonium toxicity

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Journal of Integrative Plant Biology 2022年第4期64卷 942-957页

作者： chengbin xiao Doudou Sun Beibei Liu Xianming Fang Pengcheng Li Yao Jiang Mingming He Jia Li Sheng Luan Kai He Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations School of Life SciencesLanzhou UniversityLanzhou 730000China School of Life Sciences Henan Agricultural UniversityZhengzhou 450000China School of Life Sciences Guangzhou UniversityGuangzhou 510006China Department of Plant and Microbial Biology University of CaliforniaBerkeley 94720CAUSA

Ammonium(NH_(4)^(+))and nitrate(NO_(3)^(-))are major inorganic nitrogen(N)sources for plants.When serving as the sole or dominant N supply,NH_(4)^(+)often causes root inhibition and shoot chlorosis in plants,known as ammonium toxicity.NO_(3)^(-) usually causes no toxicity and can mitigate ammonium toxicity even at low concentrations,referred to as nitrate-dependent alleviation of ammonium toxicity.Our previous studies indicated a NO_(3)^(-) efflux channel SLAH3 is involved in this process.However,whether additional components contribute to NO_(3)^(-)-mediated NH_(4)^(+)detoxification is unknown.Previously,mutations in NO_(3)^(-) transporter NRT1.1 were shown to cause enhanced resistance to high concentrations of NH_(4)^(+).Whereas,in this study,we found when the high-NH_(4)^(+) medium was supplemented with low concentrations of NO_(3)^(-),nrt1.1 mutant plants showed hyper-sensitive phenotype instead.Furthermore,mutation in NRT1.1 caused enhanced medium acidification under high-NH_(4)^(+)/Iow-NO_(3)^(-) condition,suggesting NRT1.1 regulates ammonium toxicity by facilitating H+uptake.Moreover,NRT1.1 was shown to interact with SLAH3 to form a transporter-channel complex.Interestingly,SLAH3 appeared to affect NO_(3)^(-) influx while NRT1.1 influenced NO_(3)^(-) efflux,suggesting NRT1.1 and SLAH3 regulate each other at protein and/or gene expression levels.Our study thus revealed NRT1.1 and SLAH3 form a functional unit to regulate nitrate-dependent alleviation of ammonium toxicity through regulating NO_(3)^(-) transport and balancing rhizosphere acidification.

关键词： ammonium toxicity nitrate rhizosphere acidification NRT1.1 SLAH3

The characteristics of multi-source mobility datasets and how they reveal the luxury nature of social distancing in the U.S. during the COVID-19 pandemic

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International Journal of Digital Earth 2021年第4期14卷 424-442页

作者： xiao Huang Zhenlong Li Yuqin Jiang Xinyue Ye chengbin Deng Jiajia Zhang xiaoming Li Department of Geosciences University of ArkansasFayettevilleARUSA Department of Geography University of South CarolinaColumbiaSCUSA Landscape Architecture and Urban Planning Texas A&M UniversityCollege StationTXUSA Department of Geography State University of New York at BinghamtonBinghamtonNYUSA Department of Epidemiology and Biostatistics University of South CarolinaColumbiaSCUSA Department of Health Promotion Educationand BehaviorUniversity of South CarolinaColumbiaSCUSA

This study reveals the human mobility from various sources and the luxury nature of social distancing in the U.S during the COVID-19 pandemic by highlighting the disparities in mobility dynamics from lower-income and upper-income counties.We collect,process,and compute mobility data from four different sources.We further design a Responsive Index(RI)based on the time series of mobility change percentages to quantify the general degree of mobility-based responsiveness to COVID-19 at the U.S.county level.We find statistically significant positive correlations in the RI between either two data sources,revealing their general similarity,albeit with varying Pearson’s r coefficients.Despite the similarity,however,mobility from each source presents unique and even contrasting characteristics,in part demonstrating the multifaceted nature of human mobility.The results suggest that counties with higher income tend to react more aggressively in terms of reducing more mobility in response to the COVID-19 pandemic.Most states present a positive difference in RI between their upper-income and lower-income counties,where diverging patterns in time series of mobility changes percentages can be found.The findings shed light on not only the characteristics of multi-source mobility data but also the mobility patterns in tandem with the economic disparity.

关键词： COVID-19 mobility responsive index visualization big data

Synergistic removal of aniline by carbon nanotubes and the enzymes of Delftia sp. XYJ6

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Journal of Environmental Sciences 2011年第7期23卷 1165-1170页

作者： Hai Yan xiaojing Yang Jian Chen Chunhua Yin chengbin xiao Hao Chen School of Chemical and Biological Engineering University of Science and Technology Beijing Beijing 100083 China Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Synergistic removal of aniline by carbon nanotubes and the enzymes of Delftia sp. XYJ6, a newly isolated bacterial strain for biodegrading aniline, was investigated. It showed that biodegradation rate of aniline was increased with the augment of protein concentration in cell-free extract of Delftia sp. XYJ6. The adsorption amount of aniline by multi-walled carbon nanotubes （MWCNTs） was slightly higher than that by single-walled carbon nanotubes （SWCNTs）, however the adsorption amount of protein of Delftia sp. XYJ6 by MWCNTs was lower than that by SWCNTs. Much more amount of aniline could be removed by CE of Delftia sp. XYJ6 in the presence of SWCNTs than MWCNTs, which indicated that an efficient reaction between aniline and enzymes of Delftia sp. XYJ6 on the surface of SWCNTs played a key role in the rapid enzymatic biodegradation of aniline. This study is not previously reported and may be useful in basic research and the removal of aniline from wastewater.

关键词： aniline Delftia sp. XYJ6 carbon nanotubes biodegradation adsorption

Microcystin-LR biodegradation by Sphingopyxis sp.USTB-05

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Frontiers of Environmental Science & Engineering 2011年第4期5卷 526-532页

作者： chengbin xiao Hai YAN Junfeng WANG Wei WEI Jun NING Gang PAN Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China School of Chemical and Biological Engineering University of Science and Technology BeijingBeijing 100083China

A promising bacterial strain for biodegradingmicrocystin-LR(MC-LR)as the sole carbon and nitrogensource was successfully isolated from Lake Dianchi,China.The strain was identified as Sphingopyxis sp.USTB-05,which was the first isolated MCs-biodegradingSphingopyxis sp.in China.The average biodegradationrate of MC-LR by Sphingopyxis sp.USTB-05 was 28.8mg·L^(-1)per day,which was apparently higher than those ofother bacteria reported so far.The optimal temperature andpH for both strain USTB-05 growth and MC-LRbiodegradation were 30℃and 7.0,respectively.Therelease of MC-LR from the cyanobacterial cells collectedfrom Lake Guishui and the biodegradation of MC-LR byboth strain and cell-free extract(CE)were investigated.The results indicated that MC-LR with the initialconcentration of 4.0 mg·L^(-1)in water was biodegraded bySphingopyxis sp.USTB-05 within 4 d,while MC-LR withthe initial concentration of 28.8 mg·L^(-1)could be completelyremoved in 3 h by CE of Sphingopyxis sp.USTB-05 containing 350 mg·L^(-1)protein.During enzymaticbiodegradation of MC-LR,two intermediate metabolitesand a dead-end product were observed on an HPLCchromatogram.Moreover,the similar scanning profiles ofMC-LR and its metabolic products indicate that the Addaside-chain of MC-LR was kept intact in all products.

关键词： microcystin-LR(MC-LR) biodegradation Sphingopyxis sp USTB-05 cell-free extract

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拟南芥硝态氮信号转导研究进展

西北植物学报 2020年第7期40卷 1259-1266页

作者：肖成斌何凯兰州大学生命科学学院细胞活动与逆境适应教育部重点实验室兰州730000

作为植物体内一类关键的信号分子,硝态氮调控了植物生长发育过程中的一系列生物学过程。硝态氮及其信号直接影响着农作物的氮素利用率、产量和品质。因此,深入研究硝态氮信号转导是农业可持续发展的关键。近年来,随着植物分子遗传学、... 详细信息

作为植物体内一类关键的信号分子,硝态氮调控了植物生长发育过程中的一系列生物学过程。硝态氮及其信号直接影响着农作物的氮素利用率、产量和品质。因此,深入研究硝态氮信号转导是农业可持续发展的关键。近年来,随着植物分子遗传学、生物化学等学科的迅猛发展,科学家们已经在硝态氮信号的感知、传递以及长距离信号转导等方面取得了许多突破性进展,这将有助于深入了解硝态氮信号如何调控植物生长发育过程中的各个方面。该文综述了近年来国内外有关拟南芥硝态氮信号转导方面的最新研究进展,以期为构建高效利用氮肥的新型农作物提供理论依据。

关键词：拟南芥硝态氮信号转导

Enhancing non-profiled side-channel attacks by time-frequency analysis

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Cybersecurity 2023年第4期6卷 50-75页

作者： chengbin Jin Yongbin Zhou Institute of Information Engineering Chinese Academy of SciencesBeijingChina School of Cyber Security University of Chinese Academy of SciencesBeijingChina School of Cyber Science and Engineering Nanjing University of Science and TechnologyNanjingChina

Side-channel analysis(SCA)has become an increasing important method to assess the physical security of cryptographic systems.In the process of SCA,the number of attack data directly determines the performance of SCA.With sufficient attack data,the adversary can achieve a successful SCA.However,in reality,the cryptographic device may be protected with some countermeasures to limit the number of encryptions using the same key.In this case,the adversary cannot use casual numbers of data to perform SCA.The performance of SCA will be severely dropped if the attack traces are insufficient.In this paper,we introduce wavelet scatter transform(WST)and short-time fourier transform(STFT)to non-profiled side-channel analysis domains,to improve the performance of side-channel attacks in the context of insufficient data.We design a practical framework to provide suitable parameters for WST/STFT-based SCA.Using the proposed method,the WST/STFT-based SCA method can significantly enhance the performance and robustness of non-profiled SCA.The practical attacks against four public datasets show that the proposed method is able to achieve more robust performance.Compared with the original correlation power analysis(CPA),the number of attack data can be reduced by 50–95%.

关键词： Correlation power analysis Side-channel analysis Proposed attack framework Wavelet scatter transform Short-time fourier transform

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危险废物焚烧项目回转窑运行故障分析与对策

工业炉 2019年第6期41卷 59-61页

作者：肖诚斌中国光大国际有限公司

以山东省某危险废物焚烧处置项目为例,分析回转窑在运行过程中存在的耐火材料侵蚀、窑尾结焦、窑尾浇注料脱落等问题,并提出解决措施。分析结果表明:加强物料配伍、优化废液喷枪布置、加强窑尾温度控制及改进窑尾浇注料结构等可明显改... 详细信息

以山东省某危险废物焚烧处置项目为例,分析回转窑在运行过程中存在的耐火材料侵蚀、窑尾结焦、窑尾浇注料脱落等问题,并提出解决措施。分析结果表明:加强物料配伍、优化废液喷枪布置、加强窑尾温度控制及改进窑尾浇注料结构等可明显改善回转窑运行工况,实现长周期稳定运行。

关键词：危险废物焚烧回转窑故障分析对策