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Chinese Journal of Polymer Science 2018年第9期36卷 1084-1092页

作者： Tian Xia Ya-Ping qin Ting huang College of Material Science and Engineering Chongqing University of Technology

The effects of film thickness and composition ratio on the morphology evolution of polystyrene （PS）/poly（vinyl methyl ether）（PVME） blend thin films were investigated. Diverse morphology evolutions including droplet-matrix structure, hole emergence, bicontinuous structure formation, percolation-to-droplet transition could be observed under annealing in two-phase region, depending on film thickness and composition ratio. The mechanism for these morphology variations was related to the complex effects of phase separation, dewetting and preferential wetting. The comparison between the thickness of bottom PVME layer and the twice of gyration radius 2Rg（PVME） played a dominant role in morphology control. Only when the PS/PVME film had specific film thickness and compositional symmetry, phase separation and dewetting could happen in sequence.

关键词： Phase separation Dewetting Wetting

Effect of amitriptyline on gastrointestinal function and brain-gut peptides: A double-blind trial

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World Journal of Gastroenterology 2013年第26期19卷 4214-4220页

作者： Wei huang Shu-Man jiang Lin jia Le-qing You Yao-Xing huang Yan-Mei Gong Gui-qin Wang Department of Gastroenterology Guangzhou First People's Hospital Guangzhou Medical University Department of Radiology Guangzhou First People's Hospital Guangzhou Medical University Department of Statistics Guangzhou First People's Hospital Guangzhou Medical University

AIM: To study the effects of low-dose amitriptyline (AMT) on gastrointestinal function and brain-gut peptides in healthy Chinese volunteers. METHODS: This was a double-blind, randomised, placebo-controlled, two-period cross-over trial. Twentyeight healthy volunteers were randomised and administered 1-wk treatments of AMT (12.5 mg tid) or placebo. Before and during the final two days of treatment, gastric emptying, proximal gastric accommodation and visceral sensitivity were measured by drinkingultrasonography test; the orocecal transit time (OCTT) was measured by lactulose hydrogen breath test, and fasting blood was collected. Plasma levels of ghrelin, motilin and neuropeptide Y (NPY) were measured by enzyme-linked immunosorbent assay ***: AMT slowed the OCTT (109.2 ± 29.68 min vs 96.61 ± 23.9 min, P = 0.004) but did not affect liquid gastric emptying and had no effect on proximal gastric accommodation. AMT resulted in decreases in the visual analogue scale (VAS) for difficulty in drinking 600 and 800 mL of water (3.57 ± 0.94 vs 2.98 ± 0.85, 5.57 ± 0.82 vs 4.57 ± 0.98, P < 0.01 for both), although it had no significant effect on the VAS for difficulty in drinking 200 mL and 400 mL of water. AMT significantly increased the plasma ghrelin level (442.87 ± 176.79 pg/mL vs 526.87 ± 158.44 pg/mL, P = 0.04) and the neuropeptide-Y level (890.15 ± 131.46 pg/mL vs 965.64 ± 165.63 pg/mL, P = 0.03), whereas it had no effect on the MTL level. CONCLUSION: Low-dose AMT could slow OCTT, make the stomach less sensitive and increase the plasma levels of ghrelin and NPY. Thus, we recommend the use of low-dose AMT for functional gastrointestinal disorders.

关键词： Amitriptyline Orocecal transit time Visceral hypersensitivity Gastric emptying Brain-gut peptides

Recyclable Fe_(3)O_(4)@Polydopamine(PDA) nanofluids for highly efficient solar evaporation

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Green Energy & Environment 2022年第1期7卷 35-42页

作者： qingmiao Wang Yi qin Feifei jia Shaoxian Song Yanmei Li Hubei Key Laboratory of Mineral Resources Processing and Environment Wuhan University of TechnologyWuhanHubei Province430070China Department of Mines Metallurgy and Geology EngineeringUniversity of GuanajuatoGuanajuato36000Mexico School of Resources and Environmental Engineering Wuhan University of TechnologyWuhanHubei Province430070China

Volumetric solar evaporations by using light-absorbing nanoparticles suspended in liquids(nanofluids)as solar absorbers have been widely regarded as one of the promising solutions for clean water production because of its high efficiency and low capital cost compared to traditional solar distillation ***,previous solar evaporation systems usually required highly concentrated solar irradiation and high capital cost,limiting the practical application on a large ***,for the first time in this work,polydopamine(PDA)-capped nano Fe_(3)O_(4)(Fe_(3)O_(4)@PDA)nanofluids were used as solar absorbers in a volumetric system for solar *** introduction of organic PDA to nano Fe_(3)O_(4)highly contributed to the high light-absorbing capacity of over 85%in wide ranges of 200–2400 nm because of the existence of numerous carbon bonds and pi(π)bonds in *** a result,high evaporation efficiency of 69.93%under low irradiation of 1.0 kW m^(-2)was *** to other nanofluids,Fe_(3)O_(4)@PDA nanofluids also provided an advantage in high unit evaporation ***,Fe_(3)O_(4)@PDA nanofluids showed excellent reusability and recyclability owing to the preassembled nano Fe_(3)O_(4),which significantly reduced the material *** results demonstrated that the Fe_(3)O_(4)@PDA nanofluids held great promising application in highly efficient solar evaporation.

关键词： Fe_(3)O_(4)@Polydopamine Nanofluids Volumetric solar evaporation Recyclability

Common blackbirds Turdus merula use anthropogenic structures as nesting sites in an urbanized landscape

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Current Zoology 2015年第3期61卷 435-443页

作者： YanDingWANG qin huang Sisi LAN qin ZHANG Shuihua CHEN The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education College of Life Sciences Zhejiang University Hangzhou 310058 China Zhejiang Museum of Natural History Hangzhou 310014 China College of Chemistry and Life Sciences Zhejiang Normal University Jinhua 321004 China

The common blackbird Turdus merula is one of the most highly urbanized bird species. However, to date, the use of anthropogenic structures as nesting sites in the common blackbird is rarely documented, and the factors influencing its use of the anthropogenic structures as nesting sites remain unclear. In this study, we systematically quantified and determined the factors in- fluencing the use of anthropogenie structures as nesting sites in common blackbirds in a highly urbanized city of Hangzhou, Chi- na. We searched for nests of common blackbirds during four breeding seasons from 2010 to 2013. Among the 60 nests found, 34 nests were in anthropogenic structures such as wall ledges, air condition mounts, window canopies, cable poles, guardrails, eaves, balcony frames, flowerpots and flower shelves on balconies. We found that the available anthropogenic nest sites and the availa- ble nesting trees were main factors determining the use of anthropogenic structures as nesting sites in common blackbirds. In ur- ban environments, the amount of available anthropogenic nesting sites increased significantly, whereas the number of natural nesting sites reduced greatly. Our results suggest that common blackbirds can adjust their nest sites in response to urbanization and such nesting behavior shifts may aid them to colonize urban environments. From a management viewpoint, our results indi- cate that behavioral flexibility should be taken into account for effective urban wildlife management and conservation

关键词： Adaptation Anthropogenic nest Behavioral flexibility Colonization Urbanization

甲烷在ZnO表面反应制合成气的微观机理研究

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原子与分子物理学报 2025年第6期42卷 1-9页

作者：黄琼谊楼波丁佳欣王水安华南理工大学电力学院广州510640

利用密度泛函(DFT)和过渡态理论对甲烷分子在ZnO表面的微观反应过程进行第一性原理研究,通过建立ZnO表面的吸附模型,计算了吸附能、过渡态参数和态密度,探讨了甲烷分子在氧化锌晶体表面H解离以及H_(2)和CO的生成过程,结果表明:CH_(4)在Z... 详细信息

利用密度泛函(DFT)和过渡态理论对甲烷分子在ZnO表面的微观反应过程进行第一性原理研究,通过建立ZnO表面的吸附模型,计算了吸附能、过渡态参数和态密度,探讨了甲烷分子在氧化锌晶体表面H解离以及H_(2)和CO的生成过程,结果表明:CH_(4)在ZnO(010)表面的最佳吸附位点为Zn位,吸附能为-4.65 kcal/mol,甲烷在氧化锌ZnO(010)面四次解离H(反应动力学上最有利路径)所需克服的能垒分别为38.6 kcal/mol、90.8 kcal/mol、53.2 kcal/mol和35.8 kcal/mol,其中甲烷第二次解离H_(2)过程能垒最高,是反应过程的决速步,降低该基元反应的活化能是关键,而-OH的形成抑制了-CH_(3)的解离.氧空位的形成增加活性位点的数量与提高位点的活性.甲烷与氧化锌表面的反应有两次H_(2)生成反应,第一次生成H_(2)的反应难度较大.

关键词：化学链重整甲烷反应机理密度泛函理论过渡态

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Quantification of soil organic carbon sequestration potential in cropland:A model approach

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Science China(Life Sciences) 2010年第7期53卷 868-884页

作者： qin ZhangCai huang Yao State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Agroecosystems have a critical role in the terrestrial carbon cycling *** organic carbon(SOC) in cropland is of great importance for mitigating atmospheric carbon dioxide increases and for global food *** an understanding of soil carbon saturation,we analyzed the datasets from 95 global long-term agricultural experiments distributed across a vast area spanning wide ranges of temperate,subtropical and tropical *** then developed a statistical model for estimating SOC sequestration potential in *** model is driven by air temperature,precipitation,soil clay content and pH,and explains 58% of the variation in the observed soil carbon saturation(n=76).Model validation using independent data observed in China yielded a correlation coefficient R2 of 0.74(n=19,P<0.001).Model sensitivity analysis suggested that soils with high clay content and low pH in the cold,humid regions possess a larger carbon sequestration potential than other *** a case study,we estimated the SOC sequestration potential by applying the model in Henan *** estimations suggested that carbon(C) density at the saturation state would reach an average of 32 t C ha-1 in the top 0-20 cm soil *** SOC density in the 1990s as a reference,cropland soils in Henan Province are expected to sequester an additional 100 Tg C in the future.

关键词： cropland model soil organic carbon potential saturation

Growth regularity and phase diagrams of NaLu_(0.795−x)Y_(x)F_(4) upconversion nanocrystals synthesized by automatic nanomaterial synthesizer

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Nano Research 2021年第12期14卷 4760-4767页

作者： Dan Zhang Yanhui Dong Daguang Li Heng jia Weiping qin State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun130012China

The growth regularities of nanomaterials are often concealed by the contingency of preparation. Therefore, it is always very difficult to figure out growth regularities of nanomaterials due to the accompanying undulation of products. A series of precise synthesis was performed by using an automatic nanomaterial synthesizer (ANS) in order to explore the growth regularity of complex NaREF4 (RE: rare earth) upconversion nanocrystals (UCNCs). The use of ANS significantly enhances the experimental controllability, repeatability, and success rate. Mass experimental research exhibited that the NaLu_(0.795−x)Y_(x)F_(4):Yb^(3+)/Tm^(3+) (x = 0−0.795) UCNCs can vary their sizes continuously in a wide range to accurately meet the experimenter’s design merely by controlling the concentration of Y^(3+). A notable growth regularity was obtained and intuitively shown in growth phase diagrams. Furthermore, in the case of having excellent monodispersity, pure hexagonal phase, and uniform morphology, the prepared UCNCs still retained superior upconversion luminescent (UCL) properties. The regular changes in UCL properties further confirmed the growth regularity of the UCNCs. After analyzing the experimental data, we found that NaLu_(0.795−x)Y_(x)F_(4) combined the advantages of NaYF_(4) and NaLuF_(4) hosts with desired sizes. These results provide a guidance for the exploration of growth regularities of other similar nanomaterials and also for the structure design of the required nanomaterials.

关键词： NaLu_(0.795−x)Y_(x)F_(4) upconversion nanocrystal growth regularity phase diagram automatic nanomaterial synthesizer

Limit protection design in turbofan engine acceleration control based on scheduling command governor

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Chinese Journal of Aeronautics 2021年第10期34卷 67-80页

作者： Wenhao XU Jinquan huang jiakun qin Muxuan PAN College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A new limit protection method based on Scheduling Command Governor(SCG) is proposed for imposing multiple constraints on a turbofan engine during acceleration process. A Gain Scheduling Controller(GSC) is designed for the transient state control and its stability proof is developed using Linear Matrix Inequalities(LMIs). The SCG is an add-on control scheme which manages engine limits effectively based on reference trajectory optimization. Unlike the traditional min–max architecture with switching logic, the SCG method utilizes the Linear Parameter Varying(LPV) closed-loop model to form a prediction of future constraint violation and per instant solves a constraint-admissible reference within an approximate Maximal Output Admissible Set(MOAS).The influence of the variation of engine dynamic characteristics and equilibrium points during transient state control is handled by the design of contractive sets. Simulation results on a turbofan engine component-level model show the applicability and effectiveness of the SCG method. Compared to the traditional min–max method, the SCG method has less conservativeness. In addition,the design of contractive sets makes conservativeness tunable.

关键词： Command governors Constrained control Contractive sets Gain scheduling Limit protection LPV model Turbofan engines

A Multi-Agent Spatial Logic for Scenario-Based Decision Modeling and Verification in Platoon Systems

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Journal of Computer Science & Technology 2021年第6期36卷 1231-1247页

作者： Jingwen Xu Yanhong huang jianqi Shi Shengchao qin National Trusted Embedded Software Engineering Technology Research Center East China Normal University Shanghai 200062China College of Computer Science and Software Engineering Shenzhen UniversityShenzhen 518061China

To cater for the scenario of coordinated transportation of multiple trucks on the highway,a platoon system for autonomous driving has been extensively explored in the *** such a platoon is deployed,it is necessary to ensure the safety of its driving behavior,whereby each vehicle’s behavior is commanded by the decision-making function whose decision is based on the observed driving ***,there is currently a lack of verification methods to ensure the reliability of the scenario-based decision-making process in the platoon *** this paper,we focus on the platoon driving scenario,whereby the platoon is composed of intelligent heavy trucks driving on cross-sea *** propose a formal modeling and verification approach to provide safety assurance for platoon vehicles’cooperative driving *** existing Multi-Lane Spatial Logic(MLSL)with a dedicated abstract model can express driving scene spatial properties and prove the safety of multi-lane traffic maneuvers under the single-vehicle *** cater for the platoon system’s multi-vehicle perspective,we modify the existing abstract model and propose a Multi-Agent Spatial Logic(MASL)that extends MLSL by relative orientation and multi-agent *** then utilize a timed automata type supporting MASL formulas to model vehicles’decision controllers for platoon *** the behavior of a human-driven vehicle(HDV)joining the platoon as a case study,we have implemented the model and verified safety properties on the UPPAAL tool to illustrate the viability of our framework.

关键词： autonomous driving decision-making model platoon system safety verification timed automaton

CO emission in the air return corner of the working face in shallow burial mining areas

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International Journal of Mining Science and Technology 2014年第5期24卷 617-623页

作者： Botao qin Yi Lu Yuwei jia Key Laboratory of Gas and Fire Control for Coal Mines China University of Mining and Technology School of Safety Engineering China University of Mining and Technology

In shallow burial mining areas, abnormal CO emission and the spontaneous combustion of coal are great threats to safety production at a fully-mechanised working face. In order to prevent the CO concentration in the air return corner from exceeding the critical limit, the paper studied the CO emission regularity and characteristics through theoretical analysis, experimental research and field observation. The results show that the main sources of CO emission were the spontaneous combustion of coal in the goaf and the exhaust emissions coming from underground motorised vehicles. The effect factors of CO emission were also investigated, such as seasonal climate changes, the advancing distance and advancing speed of the working face, the number of underground motorised vehicles and some other factors. In addition to these basic analyses, the influence mechanism of each influence factor was also summarised theoretically. Finally, this study researched the distribution and change law of CO concentration in the fully-mechanised working face in two aspects: controlling the change of monitoring points and time respectively. The research results provide a theoretical basis for preventing the CO concentration from exceeding the critical limit in the air return corner and reducing the possibility of spontaneous combustion of coal. Additionally, the results also provide important theoretical and practical guidelines for protecting miners' health in modern mines featuring high production and high efficiency all over the world.

关键词： Shallow burial mining area CO Emission regularity Air return corner