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Simultaneous removal of ethanol, acetaldehyde and nitrogen oxides over V-Pd/γ-Al_2O_3-TiO_2 catalyst

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Journal of Natural Gas Chemistry 2011年第2期20卷 167-172页

作者： Zhe Li Jing Wang kai He xia An Wei Huang Kechang Xie Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan 030024 Shanxi China

V-Pd/γ-Al2O3-TiO2 catalysts with different vanadium contents were prepared by a combined sol-gel and impregnation method. X-ray diffraction （XRD）, N2 adsorption-desorption （BET）, X-ray photoelectron spectroscopy （XPS） and catalytic removal of ethanol, acetaldehyde and nitrogen oxides at low temperature （〈300 ？C） were used to assess the properties of the catalysts. The results showed that the sample with 1wt% vanadium exhibited an excellent catalytic performance for simultaneous removal of ethanol, acetaldehyde and nitrogen oxides. The conversions of ethanol, acetaldehyde and nitrogen oxides at 250 ？C were 100%, 74.4% and 98.7%, respectively. V-Pd/γ-Al2O3-TiO2 catalyst with 1 wt% vanadium showed the largest surface area and higher dispersion of vanadium oxide on the catalyst surface, and possessed a larger mole fraction of V4＋ species and unique PdO species on the surface, which can be attributed to the strong synergistic effect among palladium, vanadium and the carriers. The higher activity of V-Pd/γ-Al2O3-TiO2 catalyst is related to the V4＋ and Pd2＋ species on the surface, which might be favorable for the formation of active sites.

关键词： V-Pd/γ-Al2O3-TiO2 simultaneous removal ethanol acetaldehyde nitrogen oxides

Tree species classification using deep learning and RGB optical images obtained by an unmanned aerial vehicle

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Journal of Forestry Research 2021年第5期32卷 1879-1888页

作者： Chen Zhang kai xia Hailin Feng Yinhui Yang xiaochen Du School of Information Engineering Zhejiang A&F UniversityHangzhou 311300People’s Republic of China Key Laboratory of State Forestry and Grassland Administration on Forestry Sensing Technology and Intelligent Equipment Hangzhou 311300People’s Republic of China Zhejiang Provincial Key Laboratory of Forestry Intelligent Monitoring and Information Technology Hangzhou 311300People’s Republic of China

The diversity of tree species and the complexity of land use in cities create challenging issues for tree species *** combination of deep learning methods and RGB optical images obtained by unmanned aerial vehicles(UAVs) provides a new research direction for urban tree species *** proposed an RGB optical image dataset with 10 urban tree species,termed TCC10,which is a benchmark for tree canopy classification(TCC).TCC10 dataset contains two types of data:tree canopy images with simple backgrounds and those with complex *** objective was to examine the possibility of using deep learning methods(AlexNet,VGG-16,and ResNet-50) for individual tree species *** results of convolutional neural networks(CNNs) were compared with those of K-nearest neighbor(KNN) and BP neural *** results demonstrated:(1) ResNet-50 achieved an overall accuracy(OA) of 92.6% and a kappa coefficient of 0.91 for tree species classification on TCC10 and outperformed AlexNet and VGG-16.(2) The classification accuracy of KNN and BP neural network was less than70%,while the accuracy of CNNs was relatively higher.(3)The classification accuracy of tree canopy images with complex backgrounds was lower than that for images with simple *** the deciduous tree species in TCC10,the classification accuracy of ResNet-50 was higher in summer than that in ***,the deep learning is effective for urban tree species classification using RGB optical images.

关键词： Urban forest Unmanned aerial vehicle(UAV) Convolutional neural network Tree species classification RGB optical images

EXPERIMENTAL STUDY ON THE MECHANISM OF THE RICHTMYERMESHKOV INSTABILITY AT A GAS-LIQUID INTERFACE

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Journal of Hydrodynamics 2009年第3期21卷 423-428页

作者： SHI Hong-hui ZHANG Ga DU kai JIA Hui-xia College of Mechanical Engineering and Automation Zhejiang University of Science and Technology Hangzhou 310018 China

The mechanism of the Richtmyer-Meshkov instability was experimentally studied in a vertical rectangular shock tube. The velocity of the interface driven by the shock wave was measured by a self-designed measurement system, which consists of semiconductor lasers, signal amplification circuits, digital oscilloscope and computer. Tests were carded out at several shock wave Mach numbers. In addition, the movement of the interface and the variation of the mixed zone width with time were recorded by high-speed photography. The experimental results show that the interface velocity increases with the increase of the Mach number, and the distance of the interface＇s movement and the width of the mixed zone vary with time in a linear relationship.

关键词： Richtmyer-Meshkov instability shock wave shock tube laser interface

Regulation of the phytotoxic response of Arabidopsis thaliana to the Fusarium mycotoxin deoxynivalenol

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Journal of Integrative Agriculture 2020年第3期19卷 759-767页

作者： WANG Yan YAN Hao WANG Qi ZHENG Ran xia kai LIU Yang Department of Food Science and Technology Zhejiang University of TechnologyHangzhou 310014P.R.China Zhejiang Provincial Center for Disease Control and Prevention Hangzhou 310051P.R.China Institute of Food Science and Technology Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport ProcessMinistry of Agriculture and Rural AffairsBeijing 100193P.R.China Beijing Key Laboratory of the Innovative Development of Functional Staple and the Nutritional Intervention for Chronic Disease China National Research Institute of Food and Fermentation Industries Co.Ltd.Beijing 100015P.R.China

Phytopathogenic fungi,such as Fusarium spp.,synthesize trichothecene family *** type B trichothecene,namely deoxynivalenol(DON),is highly prevalent in small-grain cereals,such as wheat,corn and *** is thought to be a virulence factor allowing plant infections and has an elicitor *** used the model plant Arabidopsis thaliana to evaluate the phytotoxic effects of DON in host *** growth of *** on media was significantly inhibited by ***,DON induced cell death in detached leaves was observed by trypan blue *** is consistent with the phenomenon of organelle changes observed at the ultrastructural *** our study,DON exposure stimulated oxidative bursts in the leaves,resulting in the concomitant down-regulation of antioxidant enzyme defense responses and up-regulation of lipid *** addition,a real-time PCR analysis revealed that the DON treatment rapidly induced the transcription of defense genes,like AtrbohC and AtrbohD,and up-regulated the transcriptional level of the ascorbic acid peroxidase *** results suggested that DON phytotoxicity might result from reactive oxygen species pathways,and that DON production by the plant pathogen Fusarium graminearum can act as an elicitor influencing plant cell fate.

关键词： deoxynivalenol Arabidopsis thaliana cell death oxidative stress

Size-tunable synthesis of gold nanorods using pyrogallol as a reducing agent

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Science China Chemistry 2015年第11期58卷 1759-1765页

作者： Yuanfu Huang kai xia Nongyue He Zhuoxuan Lu Liming Zhang Yan Deng Libo Nie Economical Forest Cultivation and Utilization of 2011 Collaborative Innovation Center in Hunan Province Hunan Key Laboratory of Green Packaging and Application of Biological Nanotechnology Hunan University of Technology State Key Laboratory of Bioelectronics School of Biological Science and Medical Engineering Southeast University

A novel and facile seed-mediated method for the preparation of monodispersed gold nanorods(GNRs) is presented by introducing pyrogallol as a reductant. Fast Fourier transformation of high-resolution transmission electron microscopy reveals that the synthesized GNRs are single crystalline. The longitudinal surface plasmon resonance of GNRs can be finely tuned by varying silver ion concentrations or seed amounts. Also, both thick(diameter >30 nm) and thin(diameter <10 nm) GNRs with exceptional monodispersity can be well prepared by this method. These findings indicate that this method has a greater performance in controlling the morphology of GNRs than that of traditional approach with ascorbic acid as a reductant.

关键词： gold nanorods seed-mediated pyrogallol size tunability

Perovskite-Inspired Lead-Free Ag2BiI5 for Self-Powered NIR-Blind Visible Light Photodetection

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Nano-Micro Letters 2020年第2期12卷 199-210页

作者： Vincenzo Pecunia Yue Yuan Jing Zhao kai xia Yan Wang Steffen Duhm Luis Portilla Fengzhu Li Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices Soochow University

In recent years,solution-processible semiconductors with perovskite or perovskite-inspired structures have been extensively investigated for optoelectronic *** particular,silver-bismuth-halides have been identified as especially promising because of their bulk properties and lack of heavily toxic *** study investigates the potential of Ag2BiI5 for near-infrared(NIR)-blind visible light photodetection,which is critical to emerging applications(e.g.,wearable optoelectronics and the Internet of Things).Self-powered photodetectors were realized and provided a near-constant≈100 mA W−1 responsivity through the visible,a NIR rejection ratio of>250,a long-wavelength responsivity onset matching standard colorimetric functions,and a linear photoresponse of>5 orders of *** optoelectronic characterization of Ag2BiI5 photodetectors additionally revealed consistency with one-center models and the role of the carrier collection distance in self-powered *** study provides a positive outlook of Ag2BiI5 toward emerging applications on low-cost and low-power NIR-blind visible light photodetector.

关键词： Perovskite-inspired semiconductor Silver bismuth iodide Self-powered photodetector NIR-blind photodetector Visible light photodetector

Coordinated organogel templated fabrication of silver/polypyrrole composite nanowires

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Chinese Chemical Letters 2011年第1期22卷 123-126页

作者： Bo Tian Li Li Ming Tang kai Chen Yu xia Xin Jin Laboratory of Advanced Materials Department of Chemical Engineering Tsinghua University Beijing 100084 China

A new method to fabricate metal/conducting polymer composite nanowires is presented by taking silver/polypyrrole composite nanowires as an example. A silver （D-coordinated organogel as template was prepared firstly, and redox-polymerization of pyrrole took place on the gel fiber, giving product of silver/polypyrrole nanowires. The silver/polypyrrole nanowires were characterized by multiple techniques. This strategy could be carried out in one-step procedure at room temperature, and it proves the utility of coordinated organogels in template synthesis of polymer nanostructures.

关键词： Coordinated organogel Template polymerization Polypyrrole Composite nanowires

Breaking the linear correlations for enhanced electrochemical nitrogen reduction by carbon-encapsulated mixed-valence Fe_(7)(PO_(4))_(6)

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Journal of Energy Chemistry 2022年第8期31卷 182-187,I0006页

作者： Lehui Ma Fanfan Xu Linlin Zhang Zhongfen Nie kai xia Mingxia Guo Mingzhu Li Xin Ding College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071ShandongChina

Electrochemical nitrogen reduction(NRR)is deemed as a consummate answer for the traditional Haber–Bosch *** the linear correlations between adsorption and transition-state energies of intermediates is vital to improve the kinetics of ammonia synthesis and obtain a less energy-intensive ***,carbon-encapsulated mixed-valence Fe_(7)(PO_(4))_(6) was prepared and applied as an electrocatalyst for high-efficiency NRR.A dramatic faradaic efficiency(FE)of 36.93%and an NH_(3) production rate of 13.1μg h^(-1) mg_(cat)^(-1) were obtained at-0.3 V versus RHE,superior to nearly all Fe-based *** and DFT calculations revealed that the superior performance was ascribed to the synergistic effect of mixed-valence iron pair,which braked the linear correlations to improve the kinetics of ammonia from collaborative hydrogenation and*NH_(3) *** work proves the feasibility of mixedvalence catalysts for nitrogen reduction and thus opening a new avenue towards artificial nitrogenfixation catalysts.

关键词： N2 reduction reaction(NRR) Mixed-valence Linear correlations Nitrogen fixation N_(2)activation

Environmental exposure during pregnancy and the risk of childhood allergic diseases

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World Journal of Pediatrics 2021年第5期17卷 467-475页

作者： Ming-Zhi Zhang Shan-Shan Chu Yan-kai xia Dan-Dan Wang Xu Wang State Key Laboratory of Reproductive Medicine.Center for Global Health School of Public Health.Nanjing Medical UniversityNanjing 211166.China Key Laboratory of Modern Toxicology of Ministry of Education School of Public Health.Nanjing Medical UniversityNanjing 211166.China Department of Endocrinology.Children's Hospital of Nanjing Medical University 72 Guangzhou Rd.Nanjing 210008China

Background Allergic diseases are one of the most common and important diseases that can exert hazardous effects on chil-dren's *** prevalence of allergic diseases in childhood is gradually increasing all over the world in recent *** causes of these diseases include anomalous immune responses and allergic inflammatory reactions,but the causes of allergic diseases in childhood are *** sources PubMed,Cochrane Library,Embase and Web of Science were searched for articles focusing on environmen-tal exposure during pregnancy and the risk of childhood allergic diseases,including asthma and atopic dermatitis,and the possible underlying *** In terms of environmental factors,allergice diseases in childhood are closely related to environmental chemical expo-sure during pregnancy,including bisphenols,phthalates acid esters,perfuorochemicals,polybrominated diphenyl ethers,and polychlorinated ***,allergic diseases in childhood are also closely associated with maternal dietary nutrition,maternal intake of drugs,such as acetylsalicylic acid(aspirin),paracetamol and antibiotics,and maternal *** Several harmful environmental factors during pregnancy can result in the interruption of the function of helper T cells(Th1/Th2),cytokines and immunoglobulins and may activate allergice reactions,which can lead to allergic diseases during childhood.

关键词： Allergic diseases Children Environment Pregnancy