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Photochemical Studies on Bicyclo[2.1.1]hexyl Derivatives:Chemical Behavior and Asymmetric Induction

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Chinese Journal of Chemistry 2014年第4期32卷 307-312页

作者： Manling Ma Feixue Xue chao Yang Wujiong xia State Key Lab of Urban Water Resource and Environment the Academy of Fundamental and Interdisciplinary SciencesHarbin Institute of TechnologyHarbinHeilongjiang 150080China

The photochemical behavior of bicyclo[2.1.1]hexyl derivatives was investigated by irradiation with a 450 W medium-pressure mercury lamp in acetonitrile solution.The irradiation of methyl bicyclo[2.1.1]hexane-5-carbonylbenzoate(1a)led to both Norrish type II cyclization and cleavage products with a molar ratio of 1∶2.2,whereas the irradiation of methyl 5-methylbicyclo[2.1.1]hexane-5-carbonylbenzoate(1b)afforded the only Norrish/Yang photocyclization compound as the sole product.Such results were illustrated by several geometric parameters for Norrish/Yang photoreaction asφ_(1),φ_(4) andβobtained from the crystal structures.Furthermore,asymmetric pho-tochemical studies using ionic chiral auxiliary technique were also conducted in the solid state.

关键词： photochemical behavior Norrish type II photoreaction geometric parameters solid state ionic chiral auxiliary

Spatial Distribution and Seasonal Variation of Hypoxic Zone in the Eastern Equatorial Indian Ocean

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Journal of Ocean University of China 2023年第4期22卷 918-929页

作者： XIE Linping WANG Baodong XIN Ming WANG Ying SUN xia WEI Qinsheng LIU Lin YUAN chao Key Laboratory of Marine Eco-Environmental Science and Technology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China

The spatial distribution and seasonal variations of the hypoxic zone in the eastern equatorial Indian Ocean were investigated using survey data collected from four cruises from 2013 to 2018.Results showed that hypoxic zone occurred all year round in the eastern equatorial Indian Ocean,and it spread southward in the shape of a double tongue at two depths with one at subsurface centered at a depth of 150 m and the other in intermediate water centered at a depth of 800 m.The southward expansion and maximum thickness of the hypoxic zone were greatest in the spring inter-monsoon and least in the summer monsoon.The hypoxic zone originated from the southward expansion of the hypoxic water in the Bay of Bengal and its spatial distribution was driven by southward output flux of mid-deep(100–1000 m)hypoxic water from the Bay of Bengal.The hypoxia southward expansion was blocked near the equator in the subsurface layer,because of mixing with multiple zonal circulations(e.g.,Wyrtki Jets and the equatorial undercurrent),which meant that the hypoxic zone extended over a smaller area than in the intermediate water.These new findings will contribute to an improved understanding of the hypoxic zone and will contribute to circulation research,particularly about intermediate circulation in the eastern equatorial Indian Ocean.

关键词： hypoxic zone spatial distribution vertical structure seasonal variation eastern equatorial Indian Ocean

Special focus on distributed storage coding

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Science China(Information Sciences) 2018年第10期61卷 5-6页

作者： xiaohu TANG Shu-Tao xia chao TIAN Qin HUANG xiang-Gen xia Southwest Jiaotong University Tsinghua University Texas A&M University Beihang University University of Delaware

Due to their low cost and feasibility, distributed storage systems (DSSs) have been widely applied in large data centers, peer-to-peer storage systems such as Ocean Store, Total Recall, and DHash++, and for storage in wireless networks. However, as the storage scale dramatically increases, reliability becomes a critical issue in applications involving the DSSs. The most efficient way to guarantee reliability is to employ erasure coding. However, it brings many new challenges that need to be addressed in terms of scalable deployment, security, efficiency, new devices, and so on.

关键词： Special focus on distributed storage coding PIR

Fabrication and Manipulation of Magnetic Composite Particles with Specific Shape and Size

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Chemical Research in Chinese Universities 2016年第6期32卷 1052-1056页

作者： SHI Qing WANG Gong LU chao xia Hong State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering JiIin University Changchun 130012 R R. China

The fabrication of microscale polyethylene glycol diacrylate（PEGDA） hydrogel particles was demon-strated via magnetic property ultraviolet（UV） lithography techniques, polydimethylsiloxane（PDMS） soft stamp pre-paration techniques and micro-nano imprint technology in this paper. The results of compositional and morphologicalcharacterizations of magnetic microparticles show that the Fe304 nanoparticles with an average diameter of 100 nmare uniformly dispersed in hydrogel. Owing to the excellent magnetism of Fe304 nanoparticles, the fabricated hydro-gel microparticles with different sizes and shapes were manipulated in water via applying an external magnetic fields.Three types of motions, translation, rotation and flip, were demonstrated with the manipulator. These microscalemagnetic PEGDA hydrogel particles have a great application potential in manufacturing process, micro/nanomotors,and machines.

关键词： Magnetic nanoparticle Hydrogel particle Micro-nano imprint Magnetic motor

ScenicPlanner： planning scenic travel routes leveraging heterogeneous user-generated digital footprints

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Frontiers of Computer Science 2017年第1期11卷 61-74页

作者： chao CHEN xia CHEN Zhu WANG Yasha WANG Daqing ZHANG School of Computer Science Chongqing University Chongqing 400044 China Center of Chongqing Automotive Collaborative Innovation Chongqing University Chongqing 400044 China School of Computer Science Northwestern Polytechnical University Xi'an 710072 China School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

To facilitate the travel preparation process to a city, a lot of work has been done to recommend a POI or a sequence of POIs automatically to satisfy users＇ needs. How- ever, most of the existing work ignores the issue of planning the detailed travel routes between POIs, leaving the task to online map services or commercial GPS navigators. Such a service or navigator in terms of suggesting the shortest travel distance or time, which cannot meet the diverse requirements of users. For instance, in the case of traveling by driving for leisure purpose, the scenic view along the travel routes would be of great importance to users, and a good planning ser- vice should put the sceneries of the route in higher priority rather than the distance or time taken. To this end, in this paper, we propose a novel framework called ScenicPlanner for route recommendation, leveraging a combination of get- tagged image and check-in digital footprints from location- based social networks （LBSNs）. First, we enrich the road net- work and assign a proper scenic view score to each road seg- ment to model the scenic road network, by extracting relevant information from get-tagged images and check-ins. Then, we apply heuristic algorithms to iteratively add road segment and determine the travelling order of added road segments with the objective of maximizing the total scenic view score while satisfying the user-specified constraints （i.e., origin, desti- nation and the total travel distance）. Finally, to validate the efficiency and effectiveness of the proposed framework, we conduct extensive experiments on three real-world data sets from the Bay Area in the city of San Francisco, which con- tain a road network crawled from OpenStreetMap, more than 31 000 geo-tagged images generated by 1 571 Flickr users in one year, and 110 214 check-ins left by 15 680 Foursquare users in six months.

关键词： scenic view travel route planning heteroge-neous digital footprint

Involvement of the autophagy-related gene BdATG8 in development and pathogenicity in Botryosphaeria dothidea

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Journal of Integrative Agriculture 2022年第8期21卷 2319-2328页

作者： LIU Na LIAN Sen ZHOU Shan-yue WANG Cai-xia REN Wei-chao LI Bao-hua College of Plant Health and Medicine Qingdao Agricultural UniversityQingdao 266109P.R.China

Botryosphaeria dothidea is a destructive fungal pathogen that causes Botryosphaeria canker and fruit ring rot on apple worldwide.Autophagy is a process of self-degradation that maintains intracellular homeostasis via lysosomal pathway.To date,the biological role of autophagy in B.dothidea remains unknown.In this study,we identified and characterized the autophagy-related gene BdATG8 in B.dothidea.BdATG8 was able to restore the defect in nitrogen starvation tolerance of Saccharomyces cerevisiae ATG8 deletion mutant.GFP-BdAtg8 was shown to be a useful marker for monitoring autophagy in B.dothidea.Target deletion of Bd ATG8(ΔBd Atg8)blocked autophagy and significantly impaired mycelial growth,conidiation and perithecium formation.In addition,ΔBdAtg8 showed significantly increased sensitivity to phytoalexin and oxidative stress,suggesting that BdATG8 plays critical roles in overcoming phytoalexin and reactive oxygen species(ROS)-mediated plant immunity.Pathogenicity assays revealed thatΔBdAtg8 almost lost ability to infect hosts.Overall,our results indicate that BdATG8 plays an important role in fungal development,stress responses and pathogenesis in B.dothidea.

关键词： Botryosphaeria dothidea autophagy BdATG8 development pathogenicity

Analysis of a Water-Cooled Unit under Different Loads

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Fluid Dynamics & Materials Processing 2023年第7期19卷 1863-1873页

作者： Daoming Shen Jinhong xia chao Gui Songtao Xue Xinxiang University Xinxiang453000China Department of Architecture Tohoku Institute of TechnologySendai982-8577Japan

In order to ensure the safe operation of the compressors used in water chillers,in the present study some interlock protections have been added to the related design.These include a low pressure protection,a high pressure protection,an exhaust temperature protection and a differential pressure protection.Some tests have been conducted by tuning the saturation suction and exhaust temperatures of the compressor through adjustment of the cold source outlet temperature and the ambient temperature.The results show that the ambient temperature increases with decreasing device load and increasing fan speed under the same saturated suction temperature;the device refrigerating capacity steps up with augmenting load and dropping saturation exhaust temperature,while it is not greatly affected by the fan speed.Moreover,the Energy efficiency ratio(COP)decreases with the rise of the saturation exhaust temperature.This parameter is not affected much by the device load and fan speed at high saturation exhaust temperature,while it improves on increasing the device load and decreasing the fan speed at low saturation exhaust temperature.

关键词： Ambient temperature cold source temperature refrigerating capacity Energy efficiency ratio(COP) fan speed load

Separation/degradation behavior and mechanism for cationic/anionic dyes by Ag-functionalized Fe_(3)O_(4)-PDA core-shell adsorbents

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Frontiers of Environmental Science & Engineering 2022年第11期16卷 153-164页

作者： Qingqing Li chao Lv xiangwei xia chao Peng Yan Yang Feng Guo Jianfeng Zhang College of Mechanics and Materials Hohai UniversityNanjing 210098China Sinosteel Maanshan General Institute of Mining Research Co. LtdMaanshan 243004China Productivity Centre of Jiangsu Province Nanjing 210042China Engineering Research Center on Utilization of Alternative Water Resources Nanjing 210000China

High-performance adsorbents have been well-studied for the removal of organic dye pollutants to promote environment remediation.In this study,an Ag nanoparticle-functionalized Fe_(3)O_(4)-PDA nanocomposite adsorbent(PDA-Fe_(3)O_(4)-Ag)was synthesized,and the adsorption/separation performance of commonly used cationic and anionic organic dyes by the PDA-Fe_(3)O_(4)-Ag adsorbent were assessed.Overall,PDA-Fe_(3)O_(4)-Ag exhibited a significantly higher adsorption capacity for cationic dyes compared to anionic dyes,the highest of which was more than 110.0 mg/g(methylene blue(MB)),which was much higher than not only the adsorption capacities of the anionic dyes in this study but also other dye adsorption capacities reported in the literature.The dye adsorption kinetics data fitted well to both the pseudo second-order kinetics model and the Langmuir isotherm model,suggesting a monolayer-chemisorption-dominated adsorption mode.Thermodynamics analysis indicated that the adsorption process was both endothermic and spontaneous.Furthermore,the PDAFe_(3)O_(4)-Ag adsorbent achieved high photodegradation removal rates of the dyes,especially neutral red(NR)and methyl orange(MO),which were 91.2%and 87.5%,respectively.With the addition of PDA-Fe_(3)O_(4)-Ag,the degradation rate constants of NR and MO increased from 0.08×10^(−2)and 0 min^(−1)to 2.11×10^(−2)and 1.73×10^(−2)min−1,respectively.The high adsorption and photocatalytic degradation performance of the PDA-Fe_(3)O_(4)-Ag adsorbent make it an excellent candidate for removing cationic and anionic dyes from the industrial effluents.

关键词： PDA Fe_(3)O_(4) Magnetic adsorbent Cationic dyes Anionic dyes

Visible-light-promoted sulfonylmethylation of imidazopyridines

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Chinese Chemical Letters 2019年第12期30卷 2295-2298页

作者： xia Mi Yuanfang Kong Jingyu Zhang chao Pi Xiuling Cui College of Pharmacy Henan University of Chinese MedicineZhengzhou 450046China College of Chemistry Henan Key Laboratory of Chemical Biology and Organic ChemistryKey Laboratory of Applied Chemistry of Henan UniversitiesZhengzhou UniversityZhengzhou 450052China

The visible light promoted C-H sulfonylmethylation of imidazopyridines with easily accessible bromomethyl sulfones under mild reaction conditions was described.This protocol provides an effective and practical access to sulfonylmethylated imidazopyridines with good functional group tolerance.The desired products were provided in moderate to excellent yields for 50 examples at room temperature.The method could also be an attractive strategy to install a methyl group on imidazopyridines.

关键词： Visible light promoted Imidazopyridine Sulfonylmethylation Radical process Desulfonylation