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Journal of Plant Ecology 2020年第6期13卷 676-682页

作者： Xi Luo Yi Zheng xiaohong Xu rui xiao Hui Guo Department of Ecology College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjingJiangsu 210095China Laboratory Center of Life Sciences College of Life SciencesNanjing Agricultural UniversityNanjing 210095China School of Life Science Henan UniversityKaifengHenan 475000China

全球变化因子(如增温和氮沉降)可能会影响生物入侵,但是这些因子如何影响入侵物种的表现并进一步调节入侵物种与本地竞争者之间的相互作用仍不清楚。本文通过为期五个月的温室实验,研究了增温(开顶式增温箱,+0.62°C)和氮添加(4.2 g N m... 详细信息

全球变化因子(如增温和氮沉降)可能会影响生物入侵,但是这些因子如何影响入侵物种的表现并进一步调节入侵物种与本地竞争者之间的相互作用仍不清楚。本文通过为期五个月的温室实验,研究了增温(开顶式增温箱,+0.62°C)和氮添加(4.2 g N m−2)对入侵物种北美车前(Plantago virginica)原产地和入侵地种群与本地车前草(Plantago asiatica)竞争的影响。实验结果表明,在增温及其与氮添加处理(W×N)的相互作用下,P.virginica的入侵种群(PV-In)和原产地种群(PV-Na)在与本地竞争者P.asiatica竞争时具有不同的生物量分配策略。其中,PV-Na在与P.asiatica竞争时增加了地下生物量,而PV-In增加了地上生物量。我们还发现,P.virginica对增温和氮添加比P.asiatica的反应更强烈。增温显著降低了P.virginica的竞争能力,这表明P.virginica比P.asiatica对增温的响应更为敏感。同样,在竞争条件下,氮添加及其和增温交互作用减少了PV-In地下生物量,但增加了PV-Na地上和总生物量。这些发现表明,P.virginica在入侵过程中改变了生物量分配策略,PV-In展示出更具弹性的竞争能力以适应环境变化(特别是增温)。这些发现可能有助于我们预测气候变化下的植物入侵并制定相应的管理策略。

关键词：入侵物种增温氮添加竞争北美车前

Controllable Bending of Bi-hydrogel Strips with Differ ent ial Swelling

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Acta Mechanica Solida Sinica 2019年第5期32卷 652-662页

作者： Yi Wu Xingpeng Hao rui xiao Ji Lin Zi Liang Wu Jun Yin Jin Qian Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Department of Engineering MechanicsZhejiang UniversityHangzhou 310027China MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Key Laboratory of 3D Printing Process and Equipment of Zhejiang ProvinceSchool of Mechanical EngineeringZhejiang UniversityHangzhou 310028China

Bi-hydrogel strips consisting of a highly swelling layer and a non-swelling layer are investigated in this study,in which the differential swelling capabilities and mismatch strain in the composite structure drive the strips into a bending configuration when being exposed to solvents.A modified analytical model originated from Timoshenko theory on bi-material beam is proposed to predict the swelling-induced bending shape of the bi-hydrogel strips,with explicit relations of bending curvature and mid-span deflection versus mismatch strain.Different sets of experiments were performed to verify the analytical model and its solutions,in which the swellinginduced mismatch strain was systematically tuned by the selection of saline concentration.The broad agreements bet ween the t heore tical and experimen tai results indicate that the modified analytical model can be used to guide the design of morphing elements by modulating layer-bylayer mismatches in gel composites to produce precise and complex shape transformations for practical applications.

关键词： Bi-hydrogel strip Hydrogel swelling Mismatch strain Shape morphing Analytical model

Earth abundant spinel for hydrogen production in a chemical looping scheme at 550℃

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Green Energy & Environment 2021年第5期6卷 780-789页

作者： Yu Qiu Li Ma Qingfeng Kong Min Li Dongxu Cui Shuai Zhang Dewang Zeng rui xiao Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing210096China

Operating chemical looping process at mid-temperatures(550–750℃)presents exciting potential for the stable production of hydrogen.However,the reactivity of oxygen carriers is compromised by the detrimental effect of the relatively low temperatures on the redox kinetics.Although the reactivity at mid-temperature can be improved by the addition of noble metals,the high cost of these noble metal containing materials significantly hindered their scalable applications.In the current work,we propose to incorporate earth-abundant metals into the ironbased spinel for hydrogen production in a chemical looping scheme at mid-temperatures.Mn0.2Co0.4Fe2.4O4 shows a high hydrogen production performance at the average rate of~0.62 mmol g^(-1) min^(-1) and a hydrogen yield of~9.29 mmol g^(-1) with satisfactory stability over 20 cycles at 550℃.The mechanism studies manifest that the enhanced hydrogen production performance is a result of the improved oxygen-ion conductivity to enhance reduction reaction and high reactivity of reduced samples with steam.The performance of the oxygen carriers in this work is comparable to those noble-metal containing materials,enabling their potential for industrial applications.

关键词： Chemical looping Mid-temperature Earth-abundant metals Spinel Hydrogen production

Efficient CO2 to CO conversion at moderate temperatures enabled by the cobalt and copper co-doped ferrite oxygen carrier

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Journal of Energy Chemistry 2020年第7期29卷 123-132,I0005页

作者： Yu Qiu Li Ma Dewang Zeng Min Li Dongxu Cui Yulin Lv Shuai Zhang rui xiao Key Laboratory of Energy Thermal conversion and control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096JiangsuChina

Chemical looping technology holds great potential on efficient CO2 splitting with much higher CO production and CO2 splitting rate than photocatalytic processes.Conventional oxygen carrier requires high temperature(typically 850–1000°C)to ensure sufficient redox activity,but the stable and high CO2 conversion is favored at a lower temperature,leading to the degrading on the reaction kinetics as well as the low CO production and CO2 splitting rate.In this paper,we prepared several ternary spinels and demonstrated their performance for chemical looping CO2 splitting at moderate temperatures.Using the promotion effect of Cu to cobalt ferrite reduction and reversible phase change of the reduced metals,Cu0.4 Co0.6 Fe2 O4 exhibits high CO2 splitting rate(144.6μmol g–1 min–1)and total CO production(9100μmol g–1)at 650°C.The high performance of this earth-abundant spinel material is also consistent in repeated redox cycles,enabling their potential in industrial use.

关键词： Chemical looping Oxygen carrier CO2 splitting Ferrite

面向乡村振兴的认养农业发展影响因素——基于咸阳市周边橙种植户的调查

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辽宁农业科学 2024年第3期 41-45页

作者：刘晓瑞杨凌职业技术学院陕西杨凌712100

为推进城郊认养农业发展,促进乡村进一步振兴,采用Logistic回归方法,从个人因素、家庭因素、生产因素和环境因素等4个维度对咸阳市周边橙种植户参与认养农业的意愿及影响因素进行研究。结果表明,咸阳周边农户参与认养农业意愿最强烈的... 详细信息

为推进城郊认养农业发展,促进乡村进一步振兴,采用Logistic回归方法,从个人因素、家庭因素、生产因素和环境因素等4个维度对咸阳市周边橙种植户参与认养农业的意愿及影响因素进行研究。结果表明,咸阳周边农户参与认养农业意愿最强烈的影响因素为农户性别、文化程度、是否村干部或合作社成员、是否参与过认养农业、家庭耕地面积、农产品价格波动与滞销情况,均在1%水平上呈现正向显著相关;农户年龄、人口数量、收入来源是否为农业种植、生产对象的需求弹性等因素在5%水平上正向显著相关;家庭收入、市场规模、政策支持、自然灾害和交通便利程度等因素未通过显著性检验。基于实证结果和结合咸阳城郊认养农业发展实际,提出提高农户对认养农业的认知水平,鼓励农户进行规模化、标准化生产,建立专项补贴贷款渠道等措施,从而更好的促进咸阳城郊认养农业发展,加快乡村振兴。

关键词：农业生活生产经营回归分析显著性检验认养农业

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决策树码率自适应算法的无数据蒸馏框架

计算机学报 2024年第1期47卷 113-130页

作者：黄天驰李朝阳张睿霄李文哲孙立峰清华大学计算机科学与技术系北京100084

码率自适应(Adaptive Bit-Rate,ABR)算法是流媒体视频传输中至关重要的技术.该算法根据当前网络情况和播放状态等因素,为下一个视频块选择合适的码率,以确保用户获得良好的体验质量(QoE).其中,基于学习的ABR算法因其不依赖传统模型和从... 详细信息

码率自适应(Adaptive Bit-Rate,ABR)算法是流媒体视频传输中至关重要的技术.该算法根据当前网络情况和播放状态等因素,为下一个视频块选择合适的码率,以确保用户获得良好的体验质量(QoE).其中,基于学习的ABR算法因其不依赖传统模型和从头学习策略的特点,表现出良好的性能,并逐渐取代需要繁琐调优的启发式ABR算法,成为研究领域的热点.然而,这些算法使用神经网络推理,导致模型参数较多,整体计算量较大,使得在实际场景中难以部署.因此,以往的研究提出了决策树蒸馏方案,即使用轻量级的决策树来提取基于学习的ABR算法的专家策略,并在线上部署这些决策树.然而,本文的实验结果表明,过去的蒸馏框架忽略了训练环境对蒸馏后策略的影响,导致策略的泛化能力较差.因此,本文提出了一种名为NIA(data-free Network-environmental Imitationbased rate Adaptation framework)的新型无数据蒸馏框架,用于生成具有更好泛化性能的决策树A BR算法.NIA通过网络环境生成模块构建多个人工网络环境,并在每次迭代训练前使用环境选择模块来选择适合的网络场景,然后与该场景进行交互,利用基于学生驱动的模仿学习算法完成决策树的蒸馏过程.本文还设计了完整的评测平台测试NIA的性能.实验表明,NIA在各种带宽数据集上展现出良好的QoE性能和泛化性能:(1)相较于启发式算法,在QoE指标上提升了1%~46%;(2)与以往的决策树蒸馏方案相比,在低带宽场景下表现相当,但在高带宽场景下提升了近1倍;(3)总体性能接近甚至超过基于学习的算法(即专家策略)的表现.

关键词：流媒体码率自适应算法无数据蒸馏

Glucocorticoids combined with tofacitinib in the treatment of Castleman’s disease:A case report

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World Journal of Clinical Cases 2022年第29期10卷 10794-10802页

作者： xiao-rui Liu Mei Tian Department of Rheumatology and Immunology Affiliated Hospital of Zunyi Medical UniversityZunyi 563003Guizhou ProvinceChina

BACKGROUND Castleman’s disease(CD),also known as vascular follicular lymphadenopathy is a rare proliferative disease of lymphoid tissue of unknown etiology that is clinically classified as unicentric CD(UCD) or multicentric CD(MCD) depending on lymph node involvement.At present,idiopathic MCD(iMCD) is treated with interleukin-6 inhibitors,but some patients have poor clinical outcomes.This paper reports on a case of iMCD that achieved a good therapeutic effect after treatment with glucocorticoids combined with tofacitinib.The relevant data are summarized and reported below.CASE SUMMARY This paper reports on a case of MCD in a 49-year-old female with persistent peritoneal effusion as the first manifestation and combined with multiple lymphadenopathies.Lymph node biopsy showed Castleman’s disease-like changes.The ascites subsided after treatment with glucocorticoids and tofacitinib,indicating that the treatment was effective.CONCLUSION The combination of glucocorticoids with tofacitinib is an effective regimen for the treatment of CD.

关键词： Castleman’s disease Multicentric Castleman’s disease Idiopathic multicentric Castleman’s disease Abdominal dropsy Tofacitinib Glucocorticoids Case report

卤化物钙钛矿金属位铋离子掺杂的调控研究进展

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物理学进展 2024年第2期44卷 73-95页

作者：黄小芮孙悦贺圣荣邢军新疆固体物理与器件重点实验室新疆大学乌鲁木齐830017 物理科学与技术学院新疆大学乌鲁木齐830017

高性能金属卤化物钙钛矿太阳能电池目前正从实验室研发向工业生产转型,并在未来全球能源领域展示了其不可估量的应用价值。为了实现高性能的金属卤化物钙钛矿太阳能电池,钙钛矿材料作为有源工作层,其性能的提高和优化过程经过了十几年,... 详细信息

高性能金属卤化物钙钛矿太阳能电池目前正从实验室研发向工业生产转型,并在未来全球能源领域展示了其不可估量的应用价值。为了实现高性能的金属卤化物钙钛矿太阳能电池,钙钛矿材料作为有源工作层,其性能的提高和优化过程经过了十几年,并已取得巨大的进步。本文以高性能卤化物钙钛矿中金属位铋离子掺杂的调制研究为重点,系统总结了卤化物钙钛矿薄膜的发展和常规制备工艺。研究表明,三元阳离子钙钛矿可以抑制黄相的形成、改变晶粒尺寸、提高稳定性等特点,成为未来高性能钙钛矿光电器件的首选。文章还对铋离子(Bi^(3+))掺杂钙钛矿体系进行了讨论,研究发现Bi3+的特殊电子结构和无毒化学性质,不仅能够提高钙钛矿的稳定性,还能灵活调控钙钛矿的光电性能,从而实现铋离子掺杂的高性能钙钛矿太阳能电池。结合目前卤化物钙钛矿太阳能电池的研究现状,我们可以预见在未来的器件优化过程中,可以将铋离子掺杂策略与三元混合阳离子钙钛矿相互结合。最后,我们展望了实现高性能金属卤化物钙钛矿太阳能电池的几个潜在研究方向。

关键词：钙钛矿铋离子掺杂太阳能电池光电性能

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城市绿色空间研究进展与展望

河北地质大学学报 2024年第1期47卷 92-98页

作者：刘畅张晓瑞合肥工业大学建筑与艺术学院安徽合肥230009 合肥工业大学数字人居环境研究实验室安徽合肥230009

随着中国城镇化、现代化进程的加快,城市人口逐渐增加,生态环境压力及土地利用压力逐渐涌现,如何使城市绿色空间用地有效利用并发挥其重要生态效益是未来发展的重要方向。城市绿色空间作为城市存量空间的重要组成部分,对改善城市生态环... 详细信息

随着中国城镇化、现代化进程的加快,城市人口逐渐增加,生态环境压力及土地利用压力逐渐涌现,如何使城市绿色空间用地有效利用并发挥其重要生态效益是未来发展的重要方向。城市绿色空间作为城市存量空间的重要组成部分,对改善城市生态环境发挥重要作用。在综合分析梳理城市绿色空间理论基础上,从城市景观生态格局和公共健康两大关键问题出发,通过CiteSpace文献计量软件分析,系统梳理了城市绿色空间的应用研究情况。现有理论和技术方法不足表现为未能充分实现多学科融合,与数字技术景观等前沿涉及较少。最后提出未来研究应从空间规划、数字技术及定量研究深入展开,完善绿色空间评价体系。

关键词：城市绿色空间景观格局公共健康城市生态定量研究

Natural gas hydrates in the Qinghai-Tibet Plateau: Characteristics, formation, and evolution

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China Geology 2021年第1期4卷 17-31页

作者： You-hai Zhu Shou-ji Pang rui xiao Shuai Zhang Zhen-quan Lu Oil and Gas Resources Survey China Geological SurveyBeijing 100083China

The Qinghai-Tibet Plateau(also referred to as the Plateau)is the largest area bearing alpine permafrost region in the world and thus is endowed with great formation conditions and prospecting potential of natural gas hydrates(NGH).Up to now,one NGH accumulation,two inferred NGH accumulations,and a series of NGH-related anomalous indicators have been discovered in the Plateau,with NGH resources predicted to be up to 8.88×10^(12) m^(3).The NGH in the Qinghai-Tibet Plateau have complex gas components and are dominated by deep thermogenic gas.They occur in the Permian-Jurassic strata and are subject to thin permafrost and sensitive to environment.Furthermore,they are distinctly different from the NGH in the high-latitude permafrost in the arctic regions and are more different from marine NGH.The formation of the NGH in the Plateau obviously couples with the uplift and permafrost evolution of the Plateau in spatial-temporal terms.The permafrost and NGH in the Qilian Mountains and the main body of the Qinghai-Tibet Plateau possibly formed during 2.0–1.28 Ma BP and about 0.8 Ma BP,respectively.Under the context of global warming,the permafrost in the Qinghai-Tibet Plateau is continually degrading,which will lead to the changes in the stability of NGH.Therefore,The NGH of the Qinghai-Tibet Plateau can not be ignored in the study of the global climate change and ecological environment.

关键词： Natural gas hydrates(NGH) Permafrost Global climate change Qinghai-Tibet Plateau