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Upwelling and anthropogenic forcing on phytoplankton productivity and community structure changes in the Zhejiang coastal area over the last 100 years

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Acta Oceanologica Sinica 2014年第10期33卷 1-9页

作者： DUAN Shanshan XING Lei ZHANG Hailong FENG xuwen YANG Haili zhao Meixun Key Laboratory of Marine Chemistry Theory and Technology (Ocean University of China) Ministry of Education Qingdao Collaborative Innovation Center of Marine Science and Technology Second Institute of Oceanography State Oceanic Administration

Phytoplankton productivity and community structure in marginal seas have been altered significantly during the past three decades, but it is still a challenge to distinguish the forcing mechanisms between climate change and anthropogenic activities. High time-resolution biomarker records of two 210Pb-dated sediment cores（#34： 28.5°N, 122.272°E; CJ12-1269： 28.861 9°N, 122.515 3°E） from the Min-Zhe coastal mud area were compared to reveal changes of phytoplankton productivity and community structure over the past 100 years. Phytoplankton productivity started to increase gradually from the 1970 s and increased rapidly after the late 1990 s at Site #34; and it started to increase gradually from the middle 1960 s and increased rapidly after the late 1980 s at Site CJ12-1269. Productivity of Core CJ12-1269 was higher than that of Core #34. Phytoplankton community structure variations displayed opposite patterns in the two cores. The decreasing D/B（dinosterol/brassicasterol） ratio of Core #34 since the 1960 s revealed increased diatom contribution to total productivity. In contrast, the increasing D/B ratio of Core CJ12-1269 since the 1950 s indicated increased dinoflagellate contribution to total productivity. Both the productivity increase and the increased dinoflagellate contribution in Core CJ12-1269 since the 1950–1960s were mainly caused by anthropogenic activities, as the location was closer to the Changjiang River Estuary with higher nutrient concentration and decreasing Si/N ratios. However, increased diatom contribution in Core #34 is proposed to be caused by increased coastal upwelling, with higher nutrient concentration and higher Si/N ratios.

关键词： biomarkers phytoplankton community structure Min-Zhe coastal mud area Changjiang Diluted Water upwelling

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Selectively Lighting Up Singlet Oxygen via Aggregation-Induced Electrochemiluminescence Energy Transfer

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ANALYTICAL CHEMISTRY 2022年第8期94卷 3718-3726页

作者： Gao, xuwen zhao, Huimin Wang, Dongyang Xu, Yuqi Zhang, Bin Zou, Guizheng Shandong Univ Sch Chem & Chem Engn Jinan 250100 Peoples R China Shandong Normal Univ Shandong Prov Engn & Tech Ctr Light Manipulat Sch Phys & Elect Shandong Prov Key Lab Opt & Photon Device Jinan 250100 Peoples R China

Singlet oxygen (O-1(2)) is an important reactive oxygen species (ROS) that is intensively involved in natural photochemical and photobiological processes. Herein, selectively lighting up O-1(2) is achieved in the aggregation-induced emission (AIE) of electrochemiluminescence (ECL) from the Zn2+-mediated AIE assembly of Au nanoclusters (Zn2+-AIE-AuNCs). Zn2+-AIE-AuNCs can exhibit efficient AIE ECL and photoluminescence (PL) along with O-1(2) generation in energy and charge transfer routes, respectively. The AIE ECL of the Zn2+-AIE-AuNCs/tripropylamine (TEA) system in carbonate buffer is located around 703 nm with the dimeric aggregate of O-1(2) as an emitter because electrochemically oxidizing coexisted Zn2+-AIE-AuNCs and TEA in carbonate buffer would promote the oxygen vacancy (Ov) of Zn2+-AIE-AuNCs, which could selectively enable the generation of emissive singlet oxygen in the energy transfer route by effectively transferring the energy from excited singlet Zn2+-AIE-AuNCs to the triplet ground state of dissolved oxygen (O-3(2)). No emissive O-1(2) is detected via electrochemically oxidizing the Zn2+-AIE-AuNCs in the case without either carbonate buffer or TEA, and the Zn2+-AIE-AuNCs/TEA system can only exhibit AIE ECL around 485 nm with Zn2+-AIE-AuNCs as the emitter in carbonate-free buffers. Photoexciting Zn2+-AIE-AuNCs merely brings out band-gap-engineered AIE PL around similar to 485 nm with Zn2+-AIE-AuNCs as the emitter, which manifests that the O-1(2) generated in the charge transfer route via photoexciting Zn2+-AIE-AuNCs is un-emissive. This work not only proposes an effective strategy for AIE with O-1(2) as an emitter but also opens a promising way to selectively light up O-1(2).

关键词： Energy Electrochemiluminescence Aggregation-induced emission Singlet oxygen

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Simple Bronsted acid catalyzed C-H functionalization: efficient access to poly-substituted pyridines

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TETRAHEDRON LETTERS 2016年第27-28期57卷 2957-2961页

作者： Lai, Shujun Ren, xuwen zhao, Jinzhong Tang, Zhuo Li, Guangxun Shanxi Agr Univ Taigu Coll Art & Sci Taigu 030800 Shanxi Peoples R China Chinese Acad Sci Chengdu Inst Biol Nat Prod Res Ctr Chengdu 610041 Sichuan Peoples R China

An exceptionally simple and environmentally friendly methodology has been developed for directly functionalizing the benzylic C-H bond of the poly-substituted pyridines with aromatic imines. Simple Bronsted acid catalysts including salicylic acid and TsOH were successfully employed. Different types of poly-substituted pyridines could be efficiently obtained with moderate yields. Traditional ways to such types of pyridines involved the aromatization of the corresponding Hantzsch 1,4-dihydropyridines, while this method greatly simplified the synthetic procedures. (C) 2016 Elsevier Ltd. All rights reserved.

关键词： Hantzsch 1,4-dihydropyridine C-H functionalization Imine Poly-substituted pyridine

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Study on Mechanical Behavior of Masonry Wall in School Building Reinforced by CFRP

Study on Mechanical Behavior of Masonry Wall in School Build...

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International Conference on Materials Engineering and Mechanical Automation (MEMA 2013)

作者： Lin, Hong Yang, zhao Wang, xuwen Ke, Xiang Wuhan Univ Technol Design & Res Inst Wuhan 430070 Peoples R China Wuhan Univ Sci & Technol Inst Urban Construct Wuhan Peoples R China

ISBN: (纸本)9783037859018

CFRP is a new kind of building materials popularly used in structure strengthening. In order to study the reinforcement technique for masonry walls of school buildings, the walls with window opening strengthened by CFRP were studied in the paper. Based on the experiment result, the finite element simulation and theoretical calculation analysis were done to study the mechanical behavior and shear capacity of the wall with window opening reinforced by CFRP. The CFRP pasted at the corner of window opening were proved to be effectively in improving shear capacity of the walls, and simple calculation formulas of shear capacity were provided in the paper, which proved to be accurate.

关键词： CFRP Masonry structure Mechanical behavior Shear capacity

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Limb remote ischemic postconditioning protects against focal ischemia in rats

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BRAIN RESEARCH 2009年 1288卷 88-94页

作者： Ren, Chuancheng Yan, Zhimin Wei, Dingtai Gao, xuwen Chen, Xiaoyuan zhao, Heng Stanford Univ Dept Neurosurg Sch Med Stanford CA 94305 USA Stanford Univ Dept Radiol Stanford CA 94305 USA Stanford Univ Dept Stanford Stroke Ctr Stanford CA 94305 USA Fudan Univ Dept Neurol Shanghai Hosp 5 Shanghai Med Sch Shanghai 200433 Peoples R China

Remote ischemic postconditioning (RIP) refers to an ischemia conducted in a distant organ that protects against a prior ischemia in another organ. We tested whether RIP protects against focal ischemia in the rat brain. Stroke was generated by a permanent occlusion of the left distal middle cerebral artery combined with a 30-min occlusion of the bilateral common carotid arteries (CCA) in male rats. After CCA release, RIP was generated by three cycles of 15-min occlusion/15-min release of the left-hind femoral artery. The results showed that rapid RIP performed immediately after CCA release reduced infarction by 67% measured at 2 days after stroke. In addition, delayed RIP initiated as late as 3 h, but not 6 h, still robustly reduced infarction by 43% 2 days after stroke. RIP's protective effect was abolished by injecting the protein synthesis inhibitor, cycloheximide, and the afferent nerve blocker, capsaicin, suggesting that RIP blocks ischemic injury by modulating protein synthesis and nerve activity. Nevertheless, rapid RIP did not reduce infarction size 2 months after stroke while it ameliorated the outcome of the behavioral test. In conclusion, RIP attenuates brain injury after focal ischemia. (C) 2009 Elsevier B.V. All rights reserved.

关键词： Stroke Cerebral ischemia Preconditioning Remote postconditioning

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Improved Local Maximal Occurrence Feature Representation for Person Re-identification 9

Improved Local Maximal Occurrence Feature Representation for...

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9th IEEE International Conference on Software Engineering and Service Science (ICSESS)

作者： Zhu, Yuanxin Yang, zhao Yao, xuwen zhao, Sai Peng, Shaohu Guangzhou Univ Sch Mech & Elect Engn Guangzhou 510006 Guangdong Peoples R China

ISBN: (纸本)9781538665657

Person re-identification is a technique to automatically search the same people in diffe..ent camera views. It is a challenging task because of the huge variations caused by different illuminations and views in images. There is an effective method tackling the problem, which learns a useful feature representation for the pedestrian images, In recent research, a featu..e rep..esentation named Local Maximal Occurrence (LOMO) achieves outstanding performance, but LOMO has a disadvantage that its robustness to illumination is not excellent. In this pape.., we propose an imp..oved LOMO representation to further reduce the impact of light. The improved LOMO feature combines Color Name feature with LOMO, because Color Name feature has strong robustness to illumination. However, Color Name feature has the weakness that it loses graphical details. The..efore, the feature is unsuitable for traditional pooling method. To overcome the disadvantage, a specific pooling method called global Gaussian pooling for Color Name feature is designed, which is based on Gaussian distribution and can weigh the different regions of an image. The important regions gain mo..e attention in matching images. The experimental results on two public available datasets demonstrate the effectiveness of our proposed approach.

关键词： component Person re-identification feature representation

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Research on the dynamic evolution of residual stress in thermal processing of diesel engine blocks based on FEM

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JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY 2021年第6期35卷 2419-2430页

作者： Tian, Guizhong Ma, Zhengyu zhao, Donghao Zhou, Honggen Jing, xuwen Xie, Zhancheng Li, Guochao Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang 212003 Jiangsu Peoples R China Jiangsu Univ Sci & Technol Jiangsu Prov Key Lab Adv Mfg Marine Mech Equipmen Zhenjiang 212003 Jiangsu Peoples R China Shaanxi Diesel Engine Heavy Ind Co Ltd Xingping 713105 Shaanxi Peoples R China

The residual stresses (RS) generated during the thermal processing processes such as casting and heat treatment is one of the fundamental causes of irreversible deformation of diesel engine bodies (DEBs). However, previous studies only focused on the RS generated from casting or the effect of annealing heat treatment on the RS in castings unilaterally, and the analytical results were far from the actual conditions. Therefore, this paper proposes a comprehensive research method to consider the whole dynamic evolution of the casting from the RS generated by casting to the stress relief by heat treatment. Numerical simulation of DEBs casting process is carried out by PROCAST, and the results of casting RS obtained from the simulation are imported into ABAQUS, and then numerical simulation of annealing heat treatment is carried out for the DEB casting model with casting RS, so as to realize the analysis of dynamic evolution of RS from casting to heat treatment.

关键词： DEB RS Numerical simulation Thermal processing parameters Response surface method

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Oral Intervention of Narirutin Ameliorates the Allergic Response of Ovalbumin Allergy

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JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022年第41期70卷 13313-13326页

作者： Shi, Xiaolei zhao, Lina Niu, Liyan Yan, Yixuan Chen, Qiushi Jin, Yongri Li, xuwen Jilin Univ Coll Food Sci & Engn Changchun 130012 Peoples R China Jilin Univ Coll Chem Changchun 130012 Peoples R China

A new intervention was investigated for the induction of oral tolerance (OT) of OVA using narirutin by in vivo and in vitro experiments combined with network pharmacology and structural analysis of molecular docking. Narirutin (and its metabolism naringenin) has effects on OT by affecting B cell function, DCs, and T cell response by prediction. It was verified that narirutin could affect B cell function of secreting antibodies, thereby reducing the ability of DCs to absorb antigens by affecting GATA3, CCR7, STAT5, and MHCII expression and regulating T cell response by suppressing Th2 and improving Treg cells in vivo. Molecular docking showed that steric hindrance effects may be the reason for weaker binding energy with targets of narirutin. However, this does not mean that it has no bioactivity, for it can inhibit mast cell degranulation. This finding is interesting because it offers the possibility of using natural compounds to promote oral tolerance.

关键词： oral tolerance narirutin food allergy OVA intervention network pharmacology

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CoFe2O4@Ti3C2 MXene nanocomposite-based broad-spectrum degradation of biotoxins

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APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY 2024年 350卷

作者： Chen, xuwen Sallach, J. Brett Ling, Wanting zhao, Xuqiang Borch, Thomas Gao, Yanzheng Nanjing Agr Univ Inst Organ Contaminant Control & Soil Remediat Coll Resources & Environm Sci Nanjing 210095 Peoples R China Univ York Dept Environm & Geog York YO10 5NG England Colorado State Univ Dept Soil & Crop Sci Ft Collins CO 80523 USA Colorado State Univ Dept Chem Ft Collins CO 80523 USA Weigang Rd 1 Nanjing 210095 Peoples R China

A significant research priority is developing a treatment method to effectively remove biotoxins commonly found in food production and the environment. A novel CoFe2O4@Ti3C2 MXene nanocomposite was fabricated by growing ferrite on MXene, and used nanocomposite to develop an oxidation-based treatment system with persulfate (PS). The ability of this system to broad-spectrum degrade mycotoxins and plant toxins was evaluated, and the catalytic and oxidation mechanisms were characterized. Co and Fe sites provide activation efficiency towards PS with adsorption energies of -21.15 and -19.63 eV, Ti site promote activation by inducing the reduction of Co and Fe. The production of reactive oxygen species via electron transfer contributed to the degradation of fourteen biotoxins with removal rates above 88%, and the frontier molecular orbital energy explained the difference in degradation extent. Electron-rich sites were predicted to help explain the degradation mechanism. The products were harmless to the ecology and human. The observations clearly indicate that Ferrite-MXene nanocomposites are viable options for broad-spectrum degradation of a wide variety of biotoxins.

关键词： CoFe2O4@Ti(3)C(2)MXene nanocomposite Biotoxins Hydrothermal synthesis Broad-spectrum degradation Persulfate

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Impacts of simulated acid rain on soil organic matter and metal aluminum and iron ions leaching from red soil in central south China

Impacts of simulated acid rain on soil organic matter and me...

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International Conference on Manufacture Engineering and Environment Engineering (MEEE)

作者： Tian, Wenjie zhao, Fangni He, xuwen Li, Fasheng China Univ Min & Technol Beijing Sch Chem & Environm Engn Beijing Peoples R China Luoyang Inst Sci & Technol Dept Environm Engn Chem Luoyang Peoples R China Chinese Res Inst Environm Sci Beijing Peoples R China

ISBN: (纸本)9781845648251;9781845648244

Acid rain is a problem of increasing agricultural, environmental, and ecological concerns worldwide. This study investigated impacts of simulated acid rain (SAR) on soil organic matter (SOM) and metal aluminum and iron ions leaching from the red soil in central south China. Laboratory experiments were performed by leaching the soil columns with the SAR at a pH range from 2.5 to 5.6 over a 20-day period. Research results showed subjected to acid rain of different acidities, dissolved organic matter (DOM), Fe and Al ions were leached out from red soil into eluate, huge leaching loss tended to occur in the initial phase of the leaching and the higher the acidity of simulated acid rain was, the bigger the loss of them from red soil. There was a very good linear correlation between DOMs and dissolved Al and Fe in the eluates, squared correlation coefficient (R-2) were respectively 0.93839 and 0.9479. These results contributed to build the theoretical foundation for assessing the potential environmental risks of groundwater.

关键词： simulated acid rain red soil soil organic matters (SOM) inorganic aluminum iron

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