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Journal of Environmental Sciences 2017年第4期29卷 196-205页

作者： dong Ren Bin Huang dan Xiong Huan He Xiangqi Meng Xuejun Pan Faculty of Environmental Science and Engineering Kunming University of Science and Technology

17α-Ethynylestradiol（EE2） in natural waters may cause adverse effects on organisms due to its high estrogenic potency. Laboratory studies were performed to study the effects of a local humic acid（LHA）, fulvic acid（LFA） and Aldrich humic acid（AHA） on the photochemical behavior and estrogenic potency of EE2. Here photolytic experiments demonstrated that pure aqueous EE2 could undergo direct and self-sensitized photodegradation at a global rate of 0.0068 hr^-*** rate of EE2 in 5.0 mg/L dissolved humic substances（DHS） was determined to be 0.0274, 0.0296 and 0.0254 hr^-1 for LHA, LFA and AHA, respectively. Reactive oxygen species（ROS） and triplet dissolved humic substances（^3DHS＊） scavenging experiments indicated that the promotion effect of DHS on EE2 photodegradation was mainly aroused by the reactions of HOU（35%–50%）,~1O2（〈10%） andDHS＊（22%–34%）. However, the photodegradation of EE2 could also be inhibited when DHS exceeded the threshold of 10 mg/L. Three hydroxylation products of EE2 were identified using GC–MS and their formation pathways were also proposed. In vitro estrogenicity tests showed that EE2 was transformed into chemicals without estrogenic potency. These findings could extend our knowledge on the photochemical behaviors of steroid estrogens in sunlit natural waters.

关键词： 17α-Ethynylestradiol Photodegradation Dissolved humic substances Reactive oxygen species Estrogenic potency

Robust video question answering via contrastive cross-modality representation learning

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Science China(Information Sciences) 2024年第10期67卷 211-226页

作者： Xun YANG Jianming ZENG dan GUO Shanshan WANG Jianfeng dong Meng WANG School of Information Science and Technology University of Science and Technology of China Institute of Artificial Intelligence Hefei Comprehensive National Science Center School of Computer Science and Information Engineering Hefei University of Technology Institutes of Physical Science and Information Technology Anhui University School of Computer Science and Technology Zhejiang Gongshang University

Video question answering(VideoQA) is a challenging yet important task that requires a joint understanding of low-level video content and high-level textual semantics. Despite the promising progress of existing efforts, recent studies revealed that current VideoQA models mostly tend to over-rely on the superficial correlations rooted in the dataset bias while overlooking the key video content, thus leading to unreliable results. Effectively understanding and modeling the temporal and semantic characteristics of a given video for robust VideoQA is crucial but, to our knowledge, has not been well investigated. To fill the research gap, we propose a robust VideoQA framework that can effectively model the cross-modality fusion and enforce the model to focus on the temporal and global content of videos when making a QA decision instead of exploiting the shortcuts in datasets. Specifically, we design a self-supervised contrastive learning objective to contrast the positive and negative pairs of multimodal input, where the fused representation of the original multimodal input is enforced to be closer to that of the intervened input based on video perturbation. We expect the fused representation to focus more on the global context of videos rather than some static keyframes. Moreover, we introduce an effective temporal order regularization to enforce the inherent sequential structure of videos for video representation. We also design a Kullback-Leibler divergence-based perturbation invariance regularization of the predicted answer distribution to improve the robustness of the model against temporal content perturbation of videos. Our method is model-agnostic and can be easily compatible with various VideoQA backbones. Extensive experimental results and analyses on several public datasets show the advantage of our method over the state-of-the-art methods in terms of both accuracy and robustness.

关键词： video question answering cross-modality fusion contrastive learning cross-media reasoning

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The Studies of Rhodium-catalyzed Ring Opening Reaction of N-Boc-azabenzonorbornadiene with Heteroatom Nucleophiles

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Chinese Chemical Letters 2006年第6期17卷 717-719页

作者： er Chang LIU Ding Qiao YANG Ying Feng HAN Jian Xia dong School of Chemisry and Environment South China Normal UniversityGuangzhou510006

A rhodium-catalyzed ring opening reaction of N-Boc-azabenzonorbornadiene with heteroatom nucleophiles was described. Piperidine and piperazine＇s derivatives were nucleophiles in this reaction. The yields of the produ... 详细信息

关键词： Rhodium-catalyzed N-Boc-azabenzonorbornadiene nucleophiles ring opening.

Transmissive-detected laser speckle contrast imaging for blood flow monitoring in thick tissue: from Monte Carlo simulation to experimental demonstration

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Light(Science & Applications) 2021年第12期10卷 2492-2506页

作者： dong-Yu Li Qing Xia Ting-Ting Yu Jing-Tan Zhu dan Zhu Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology430074 WuhanHubeiChina MoE Key Laboratory for Biomedical Photonics Huazhong University of Science and Technology430074 WuhanHubeiChina

Laser speckle contrast imaging(LSCI)is a powerful tool to monitor blood flow distribution and has been widely used in studies of microcirculation,both for animal and clinical ***,LSCI usually works on reflectivedetected ***,it could provide promising temporal and spatial resolution for in vivo applications only with the assistance of various tissue windows,otherwise,the overlarge superficial static speckle would extremely limit its contrast and ***,we systematically investigated the capability of transmissive-detected LSCI(TR-LSCI)for blood flow monitoring in thick *** Monte Carlo simulation,we theoretically compared the performance of transmissive and reflective *** was found that the reflective-detected mode was better when the target layer was at the very surface,but the imaging quality would rapidly decrease with imaging depth,while the transmissivedetected mode could obtain a much stronger signal-to-background ratio(SBR)for thick *** further proved by tissue phantom,animal,and human experiments that in a certain thickness of tissue,TR-LSCI showed remarkably better performance for thick-tissue imaging,and the imaging quality would be further improved if the use of longer wavelengths of near-infrared ***,both theoretical and experimental results demonstrate that TR-LSCI is capable of obtaining thick-tissue blood flow information and holds great potential in the field of microcirculation research.

关键词： reflective thick speckle

Raising on Water Stocking Density Reduces Geese Reproductive Performances via Water Bacteria and Lipopolysaccharide Contaminations in “Geese-Fish” Production System

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Agricultural Sciences in China 2011年第9期10卷 1459-1466页

作者： JIANG dan-li LIU Li WANG Cong-li CHEN Fang SUN Ai-dong SHI Zhen-dan College of Animal Science South China Agricultural University Guangzhou 510642 P.R.China College of lnformatics South China Agricultural University Guangzhou 510642 P.R. China

This study was carried out to unravel the mechanism of reductions in production performances in high stocking density geese flocks during summer months in ＂geese-fish＂ production system. Experiment 1 observed the water bacterial growth, lipopolysaccharde concentrations in water and geese blood, and geese reproductive performances from summer to winter, in two flocks with varying on water stocking densities. Results showed that counts of total bacteria, Escherichia coli and Salmonella in water, as well as water and geese plasma LPS concentrations, exhibited a tendency decreasing from the highest levels in summer, to intermediate levels in autumn, and to the lowest values in winter. Such seasonal decreases in bacteria and LPS concentrations were associated with similar seasonal decreases in embryo mortality during incubation. In addition, embryos dead or showing development retardation by day 25 of incubation contained copious LPS in allantoic fluid, in contrast to the negligible amount in normal developing embryos. Raising on water stocking density elevated bacteria counts, LPS concentrations in water and geese plasma, and decreased egg fertility but increased embryo mortality during incubation. In experiment 2, exogenous LPS treatment to the geese depressed egg laying, reduced egg hatchability, caused sickness behavior in the goslings hatched. In experiment 3, exogenous LPS directly administered to day 8 and 18 embryos during incubation dose dependently increased mortality and decreased hatchability, and caused sickness behavior in the goslings hatched. It is concluded that the raising on water geese stocking density stimulates pathogenic bacteria growth in water, which via LPS contamination impaires embryo development in incubation and therefore reduces geese reproductive performance and gosling quality during the hot summer months.

关键词： water bacteria growth lipopolysaccharide production performances geese

Comparison of the corrosion behavior of AM60 Mg alloy with and without self-healing coating in atmospheric environment

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Journal of Magnesium and Alloys 2021年第4期9卷 1224-1237页

作者： Yingwei Song dan Liu Weineng Tang Kaihui dong Dayong Shan En-Hou Han Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Baosteel Central Research Institute(R&D Center) China Baowu Group655 Fujin RoadShanghai 201900China

Coatings on the surface of Mg alloys are inevitably damaged during their practical applications,and corrosion can easily initiate from the damaged areas to accelerate the failure of Mg parts.A dual self-healing coating has already been developed to solve this problem in our previous *** the practical application of this coating,it is necessary to investigate its service behavior in atmospheric ***,the corrosion behavior of AM60 Mg substrate with and without the self-healing coating was compared in Shenyang industrial atmospheric *** results show that the enrichment of sediments and rainwater on the scratch areas can accelerate the corrosion of the exposed Mg *** inhibitors can be released from the damaged coating to inhibit *** dual self-healing coating shows better inhibition ability to narrow scratches due to the higher inhibitor concentration and less ***,the coating with wide scratches displays enough inhibition ability as *** dual self-healing coating is a good alternative for Mg alloy parts in the practical applications.

关键词： Self-healing coating Micro-arc oxidation(mao)film Atmospheric corrosion Mg alloy Inhibitor Sediments

Texture Evolution, Formability and Ridging Resistance of a Sn-bearing Ferritic Stainless Steel Under Different Hot Band Annealing Temperatures

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Acta Metallurgica Sinica(English Letters) 2019年第11期32卷 1362-1372页

作者： Tong He-dan Guo Yang Bai Tong He dan Guo Xiu-Ting Liu Fang-Yuan Shao Yan-dong Liu Key Laboratory for Anisotropy and Texture of Materials of Ministry of Education Northeastern UniversityShenyang 110819China Research Academy Northeastern UniversityShenyang 110819China

The microstructure, texture evolution and spatial orientation distribution during cold rolling and the subsequent annealing as well as formability and ridging of a Sn-bearing ferritic stainless steel under different hot band annealing temperatures were investigated. The four hot bands with annealing temperatures of 900, 950, 1000 and 1050 °C were all cold-rolled to 80% reductions and then were annealed at the same temperature of 900 °C. The results show that optimizing hot band annealing process is benefi cial to reduce the amount of {001} grains and weaken the texture intensity, and thus, to reduce ridging and improve formability. In the present study, the fi nal sheets with hot band annealing temperature of 900 °C possess small and inhomogeneous grains with a large amount of {001} orientations, which deteriorates the formability and increases the ridging. In comparison, the fi nal sheets with hot band annealing temperature of 950 °C are comprised of uniform and equiaxed //ND(ND: normal direction) recrystallized grains with a high texture intensity favorable for the improvement in r value and surface quality. However, when hot band annealing temperature further increases to 1000 and 1050 °C, it shows a sharp decrease in r value and a remarkable increase in ridging as a result of a reduction in γ-fi ber texture intensity and an increase in grain size in the fi nal sheets. Suitable controlling and optimizing hot band annealing process is essential to improve the formability and reduce the ridging.

关键词： Ferritic stainless steel Texture Formability Ridging

Successful treatment of pyogenic ventriculitis caused by extensively drug-resistant Acinetobacter baumannii with multi-route tigecycline: A case report

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World Journal of Clinical Cases 2021年第3期9卷 651-658页

作者： Wei Li dan-dong Li Bo Yin dong-dong Lin Han-Song Sheng Nu Zhang Department of Neurosurgery The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

BACKGROUND Pyogenic ventriculitis caused by extensively drug-resistant Acinetobacter baumannii(***)is one of the most severe complications associated with ***,limited therapeutic options exist for the treatment of *** ventriculitis due to the poor penetration rate of most antibiotics through the blood-brain *** SUMMARY A 68-year-old male patient with severe traumatic brain injury developed pyogenic ventriculitis on postoperative day 24 caused by extensively drug-resistant *** susceptible to tigecycline *** treatment was accomplished through multi-route administration of tigecycline,including intravenous combined with continuous ventricular irrigation plus intraventricular *** pus was cleared on the 3rd day post-irrigation,and cerebrospinal fluid cultures were negative after 12 *** Our findings suggest that multi-route administration of tigecycline can be a therapeutic option against pyogenic ventriculitis caused by extensively drugresistant ***.

关键词： Pyogenic ventriculitis Acinetobacter baumannii Extensively drug-resistant Tigecycline Ventricular irrigation Case report

Thermal,Mechanical and Rheological Properties of Biodegradable Poly(propylene carbonate) and Poly(butylene carbonate) Blends

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Chinese Journal of Polymer Science 2015年第3期33卷 444-455页

作者： dan-dan Wu Wu Li Yan Zhao Yun-jiao Deng 张会良 Hui-xuan Zhang Li-song dong Changchun University of Technology Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied Chemistry

Poly（propylene carbonate）（PPC） was melt blended in a batch mixer with poly（butylene carbonate）（PBC） in an effort to improve the toughness of the PPC without compromising its biodegradability and biocompatibility. DMA results showed that the PPC/PBC blends were an immiscible two-phase system. With the increase in PBC content, the PPC/PBC blends showed decreased tensile strength, however, the elongation at break was increased to 230% for the 50/50 PPC/PBC blend. From the tensile strength experiments, the Pukanszky model gave credit to the modest interfacial adhesion between PPC and PBC, although PPC/PBC was immscible. The impact strength increased significantly which indicated the toughening effects of the PBC on PPC. SEM examination showed that cavitation and shear yielding were the major toughening mechanisms in the blends subjected the impact tests. TGA measurements showed that the thermal stability of PPC decreased with the incorporation of PBC. Rheological investigation demonstrated that the addition of PBC reduced the value of storage modulus, loss modulus and complex viscosity of the PPC/PBC blends to some extent. Moreover, the addition of PBC was found to increase the processability of PPC in extrusion. The introduction of PBC provided an efficient and novel toughened method to extend the application area of PPC.

关键词： Biodegradable Poly(propylene carbonate) Poly(butylene carbonate) Blends,

Tailoring Carbon Distribution inα/γPhase of Ductile Iron and Its Effects on Thermal Conductivity

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Journal of Wuhan University of Technology(Materials Science) 2023年第3期38卷 645-651页

作者：刘琛杜玉洲 YING Tao ZHANG Liandong ZHANG Xinyu dong dan JIANG Bailing School of Materials Science and Engineering Xi'an University of TechnologyXi'an 710048China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China The Second Afflated Hospital of Xi'an Jiaotong University Xi'an 710004China

The effects of carbon distribution on the microstructure and thermal conductivity of ductile iron were investigated in the present *** microstructure of as-cast and quenched ductile iron were characterized by OM and *** showed that the microstructure of as-cast ductile iron was composed of spheroidal graphite,ferrite with the volume of 80%,and a small amount of pearlite,and quenched ductile iron was composed of spheroidal graphite,coarse/fine acicular martensite(α_(M)phase)and high-carbon retained austenite(γphase).The volume fraction of retained austensite and its carbon content for direct quenched ductile iron and tepmered ductile iron were quantitatively analysed by *** revealed that carbon atoms diffused fromα_(M)phase toγphase during tempering at low temperatures,which resulted in carbon content in retainedγphase increasing from 1.2 wt%for the direct quenched sample to about 1.9 wt%for the tempered ***,the lattice distortion was significantly reduced and gave rise to an increase of thermal conductivity for ductile iron.

关键词： ductile iron carbon distribution retained austenite thermal conductivity lattice distortion