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The Dominant Glutamic Acid Metabolic Flux to Produce γ-Amino Butyric Acid over Proline in Nicotiana tabacum Leaves under Water Stress Relates to its Significant Role in Antioxidant Activity

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Journal of Integrative Plant Biology 2011年第8期53卷 608-618页

作者： Cuili Liu Li zhao guanghui Yu Key Laboratory for Biotechnology of the State Ethnic Affairs Commission College of Life Sciences South-Central University for Nationalities Wuhan 430074 China

γ-Amino butyric acid （GABA） and proline play a crucial role in protecting plants during various environmental stresses. Their synthesis is from the common precursor glutamic acid, which is catalyzed by glutamate decarboxylase and △1-pyrroline-5-carboxylate synthetase respectively. However, the dominant pathway under water stress has not yet been established. To explore this, excised tobacco leaves were used to simulate a water-stress condition. The results showed GABA content was much higher than that of proline in leaves under water-deficit and non-water-deficit conditions. Specifically, the amount of GABA significantly increased compared to proline under continuous water loss for 16 h, indicating that GABA biosynthesis is the dominant pathway from glutamic acid metabolism under these conditions. Quantitative reverse transcription polymerase chain reaction and protein Western gel-blot analysis further confirmed this. To explore the function of GABA accumulation, a system producing superoxide anion （O 2 - ）, peroxide hydrogen （H 2 O 2 ）, and singlet oxygen （ 1 O 2 ） was employed to investigate the scavenging role on free-radical production. The results demonstrated that the scavenging ability of GABA for O 2 - , H 2 O 2 , and 1 O 2 was significantly higher than that of proline. This indicated that GABA acts as an effective osmolyte to reduce the production of reactive oxygen species under water stress.

关键词： glutamic acid proline reactive oxygen species water stress γ-amino butyric acid.

Direction synthesis in DOA estimation for monostatic multiple input multiple output (MIMO) radar based on synthetic impulse and aperture radar (SIAR) and its performance analysis

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Science China(Technological Sciences) 2008年第6期51卷 656-673页

作者： zhao guanghui CHEN BaiXiao ZHU ShouPing National Key Lab for Radar Signal Processing Xidian UniversityXi’an 710071China

A new direction synthetic method for monostatic multiple input multiple output (MIMO) radar is presented based on synthetic impulse and aperture radar (SIAR) system. Concerned with the monostatic MIMO radar which simultaneously emits orthogonal signals with multi-carrier-frequency and possesses sparsely distributed transmitting and receiving arrays with respective location, as well as the situation for the presence of multipath propagation in the low flying target’s echo, the method integrates the aperture of the transmitting arrays with the receiving arrays to form the digital beam-forming (DBF) in azimuth and elevation dimensions. And a study has been made of planar general MUSIC algorithm based on decorrelating the multipath signals of multi-carrier-frequency MIMO radar. Through compensat-ing the phase delay of both the transmitting and the receiving arrays and synthe-sizing the transmitting beam in two dimensions at the receiver, the angular resolu-tion and measurement accuracy are improved and the computational complexity is reduced after transforming the three-dimensional (3D) parameter estimation prob-lem into a two-dimensional (2D) one. Finally, the Cramer-Rao Bounds (CRBs) of DOA estimation for azimuth and elevation is put forward with the exsiting multipath propagation. Results of computer simulation demonstrate the validity of the new method.

关键词： SIAR monostatic MIMO radar multipath propagation super resolution general MUSIC algorithm Cramer-Rao Bounds

Hot deformation behavior of a novel bimetal consisting of BTW1 and Q345R characterized by processing maps

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Frontiers of Mechanical Engineering 2019年第4期14卷 489-495页

作者： Pengtao LIU Lifeng MA Weitao JIA Tao WANG guanghui zhao College of Mechanical Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi Provincial Key Laboratory of Metallurgical Equipment Design and Technology Taiyuan University of Science and TechnologyTaiyuan 030024China College of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China

Only a few studies have been conducted on the flow behavior of the novel BTW1/Q345R bimetal,which is widely used in coal *** this work,compression tests were conducted on BTW1/Q345R bimetal at a temperature range of 950°C–1200°C and strain rates of 0.05,0.5,5,and 15 s^−1 by using a Gleeble-3800 thermomechanical simulator.A constitutive equation was validated by referring to the Arrhenius equation during the characterization of hot *** computed apparent activation energy of the BTW1/Q345R bimetal was 360 kJ/mol,and processing maps under different strain conditions were *** of the stress-strain relationship revealed that work hardening exerted a dominant effect on the thermal deformation of the BTW1/Q345R *** processing maps predicted that the optimal processing interval will increase with *** showed that thermal deformation of the BTW1/Q345R bimetal should proceed when the temperature range varies from 1182°C to 1200°C and the strain rate interval is from 4.2 to 15 s^−1.

关键词： BTW1/Q345R bimetal constitutive equation processing map work hardening

A high quality image reconstruction method based on nonconvex decoding

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Science China(Information Sciences) 2013年第11期56卷 184-193页

作者： zhao guanghui SHEN FangFang WANG ZhengYang WU WeiJia SHI GuangMing LIU DanHua School of Electronic Engineering Xidian University

The article proposes a fast reconstruction algorithm for l0≤p≤1 norm nonconvex model,called Gradient projection nonconvex sparse recovery(GPNSR),which makes a good performance in high-quality image *** apply the GPNSR into canonical multiple description coding theory and propose a robust high-quality compressed sensing-based coding *** with iterative weighted technique and fast gradient descent method,the proposed method implicitly implements matrix inverse operations to highly reduce the storage *** the weighted norm method is taken to optimize the descent steps,which highly increases convergent speed of the *** an image has sparse Fourier representations as an example,the paper presents the detailed image sparse coding and fast reconstruction *** integrating the compressive sensing multi-description coding framework,the simulation demonstrates the superior reconstruction performance of the proposed *** importantly,with p close to zero,the reconstruction performance of GPNSR can approximate that of l0 norm optimization result.

关键词： l0≤p≤1 norm nonconvex decoding multiple description coding iteration weighting

Molecular dynamics simulation of graphene sinking during chemical vapor deposition growth on semi-molten Cu substrate

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npj Computational Materials 2020年第1期6卷 1548-1557页

作者： Ziwei Xu guanghui zhao Lu Qiu Xiuyun Zhang Guanjun Qiao Feng Ding School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China Centre for Multidimensional Carbon Materials Institute for Basic ScienceUlsan 44919Korea School of Materials Science and Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Korea College of Physics Science and Technology Yangzhou UniversityYangzhou 225002China

Copper foil is the most promising catalyst for the synthesis of large-area,high-quality monolayer ***,it has been found that the Cu substrate is semi-molten at graphene growth *** this study,based on a self-developed C–Cu empirical potential and density functional theory(DFT)methods,we performed systematic molecular dynamics simulations to explore the stability of graphene nanostructures,i.e.,carbon nanoclusters and graphene nanoribbons,on semi-molten Cu substrates.

关键词： dynamics semi monolayer

Spatial Distribution and Sources Identification of Polycyclic Aromatic Hydrocarbons in Wolong Lake, Northeast China

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Chinese Geographical Science 2017年第6期27卷 1003-1012页

作者： zhao guanghui CHANG Wenyue YAN Jinxia LI Xiaojun TONG Dongli zhao Ranran Sharley James DAVID TAI Peidong Shenyang Academy of Environmental Sciences Shenyang 110167 China School of Environmental & Municipal Engineering North China University of Water Resources and Electric Power Zhengzhou 450045 China Institute of Applied Eeology Chinese Academy of Sciences Shenyang 110016 China Centre for Aquatic Pollution Identification and Management University of MeN bourne School of BioSciences Victoria 3010 Australia

The aquatic ecosystem maybe significantly affected by polycyclic aromatic hydrocarbons(PAHs) released from fresh water sediments. In order to protect biodiversity, the spatial distribution and sources of PAHs in the sediment of Wolong Lake in Northeast China were studied. A total of 17 surface sediment samples were collected and 12 PAHs were analyzed. The results were as follows. The concentration of total PAHs(TPAHs) ranged between 1412.9 μg/kg and 3948.3 μg/kg(dry weight). Indeno [1, 2, 3-c, d] pyrene was the dominant contaminant which accounted for 87%–98% of TPAHs. Diagnostic ratios of PAHs and principal component analysis showed that biomass combustion and vehicle emissions were likely to be the dominant sources of PAHs in the sediment. PAHs can be considered safe in the context of environmental and human health protection, based on the overall toxicity. Individual PAHs were positively correlated with total organic carbons. These results will be helpful to control PAHs and protect the aquatic ecosystem in the lake.

关键词： polycyclic aromatic hydrocarbons (PAHs) Wolong Lake lake sediment contaminant oxicity spatial distribution

Berlin Green Framework‑Based Gas Sensor for Room‑Temperature and High‑Selectivity Detection of Ammonia

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Nano-Micro Letters 2021年第4期13卷 146-158页

作者： Tingqiang Yang Lingfeng Gao Wenxuan Wang Jianlong Kang guanghui zhao Delong Li Wen Chen Han Zhang Institute of Microscale Optoelectronics Collaborative Innovation Centre for Optoelectronic Science and TechnologyKey Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen Key Laboratory of Micro‑Nano Photonic Information TechnologyGuangdong Laboratory of Artificial Intelligence and Digital Economy(SZ)Shenzhen UniversityShenzhen 518060People’s Republic of China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070People’s Republic of China Research Center for Materials Genome Engineering Wuhan University of TechnologyWuhan 430070People’s Republic of China

Ammonia detection possesses great potential in atmosphere environmental protection,agriculture,industry,and rapid medical ***,it still remains a great challenge to balance the sensitivity,selectivity,working temperature,and response/recovery *** this work,Berlin green(BG)framework is demonstrated as a highly promising sensing material for ammonia detection by both density functional theory simulation and experimental gas sensing *** in BG framework offers abundant active sites for ammonia absorption,and the absorbed ammonia transfers sufficient electron to BG,arousing remarkable enhancement of *** BG framework shows remarkable response to ammonia at 50–110°C with the highest response at 80°C,which is jointly influenced by ammonia’s absorption onto BG surface and insertion into BG *** sensing performance of BG can hardly be achieved at room temperature due to its high *** of conductive Ti3CN MXene overcomes the high resistance of pure BG framework,and the simply prepared BG/Ti3CN mixture shows high selectivity to ammonia at room temperature with satisfying response/recovery speed.

关键词： Berlin green framework Gas sensor Ammonia Room temperature High selectivity

BROADCAST SCHEDULING WITH MIMO LINKS IN MULTI-HOP AD HOC NETWORKS

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Journal of Electronics(China) 2007年第4期24卷 477-483页

作者： Zhang guanghui Li Jiandong zhao Min Li Changle State Key Lab. of ISN Information Science Inst. Broadband Wireless Communications Lab. Xidian University Xi＇an 710071 China

As the current medium access control protocols with Multiple Input Multiple Output （MIMO） links only bear point to point service, broadcast scheduling algorithm in ad hoc networks with MIMO links is proposed. The key to the proposed broadcast scheduling algorithm is the time slot scheduling algorithm which guarantees collisi~）n-free transmissions for every node and the mini- mum frame length. The proposed algorithm increases the simultaneous transmissions of MIMO links efficiently. Due to the interference null capacity of MIMO links, the interference node set of each node can decrease from two-hop neighbors to one-hop neighbors possibly. Simulation results show that our algorithm can greatly improve network capacity and decrease average packet delay.

关键词： Multiple Input Multiple Output (MIMO) Time Division Multiple Access (TDMA) Broadcast Multihop ad hoc network

Spatial variations in CO2 fluxes in a subtropical coastal reservoir of Southeast China were related to urbanization and land-use types

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Journal of Environmental Sciences 2021年第11期33卷 206-218页

作者： Yifei Zhang Min Lyu Ping Yang Derrick Y.F.Lai Chuan Tong guanghui zhao Ling Li Yuhan Zhang Hong Yang Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education Fujian Normal UniversityFuzhou 350007China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China School of Urban and Rural Construction Shaoyang UniversityShaoyang 422000China Department of Geography and Resource Management The Chinese University of Hong KongHong KongChina College of Environmental Science and Engineering Fujian Normal UniversityFuzhou 350007China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control(AEMPC)School of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China Department of Geography and Environmental Science University of ReadingReading RG66AB United Kingdom

Carbon dioxide(CO_(2))emissions from aquatic ecosystems are important components of the global carbon cycle,yet the CO_(2)emissions from coastal reservoirs,especially in developing countries where urbanization and rapid land use change occur,are still poorly *** this study,the spatiotemporal variations in CO_(2)concentrations and fluxes were investigated in Wenwusha Reservoir located in the southeast coast of ***,the mean CO_(2)concentration and flux across the whole reservoir were 41.85±2.03μmol/L and 2.87±0.29 mmol/m2/h,respectively,and the reservoir was a consistent net CO_(2)source over the entire *** land use types and urbanization levels in the reservoir catchment significantly affected the input of exogenous carbon *** mean CO_(2)fluxwasmuch higher from waters adjacent to the urban land(5.05±0.87 mmol/m2/hr)than other land use *** with larger input of exogenous substance via sewage discharge and upstream runoff were often the hotspots of CO_(2)emission in the *** results suggested that urbanization process,agricultural activities,and large input of exogenous carbon could result in large spatial heterogeneity of CO_(2)emissions and alter the CO_(2)biogeochemical cycling in coastal *** studies should characterize the diurnal variations,microbial mechanisms,and impact of meteorological conditions on reservoir CO_(2)emissions to expand our understanding of the carbon cycle in aquatic ecosystems.

关键词： Carbon dioxide fluxes Spatiotemporal dynamics Land use Urbanization Anthropogenic activities Coastal reservoir