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餐厨沼液滴灌水盐调控对土壤环境和西兰花产量的影响

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节水灌溉 2024年第5期 10-17页

作者：李娜奚辉周扬陈喜靖喻曼浙江省农业科学院环境资源与土壤肥料研究所杭州310021 浙江农林大学环境与资源学院杭州311300

为探究和评价餐厨沼液滴灌对土壤环境和作物生长的影响,通过盆栽试验研究氮磷钾等浓度施用条件下,滴灌水盐调控不同土壤水基质势水平[-20 kPa(W)和-30 kPa(P)]和餐厨沼液比例[0%(0)、10%(1)、16.7%(2)、25%(3)和33.3%(4)]对土壤盐分、... 详细信息

为探究和评价餐厨沼液滴灌对土壤环境和作物生长的影响,通过盆栽试验研究氮磷钾等浓度施用条件下,滴灌水盐调控不同土壤水基质势水平[-20 kPa(W)和-30 kPa(P)]和餐厨沼液比例[0%(0)、10%(1)、16.7%(2)、25%(3)和33.3%(4)]对土壤盐分、无机氮含量和西兰花生长的影响。结果表明:土壤水基质势水平对土壤盐分有显著的影响,与P相比,W降低表层土壤饱和泥浆提取液电导率(eCe)13.0%;土壤eCe随沼液比例的增加而升高,33.3%沼液处理比其他处理高23.1%~46.8%。沼液比例对土壤铵态氮含量影响显著,0%沼液处理表层铵态氮是其他处理的2.2~3.0倍;餐厨沼液灌溉会降低西兰花产量,P_(2)、P_(3)和P_(4)处理下降显著。综合评价结果表明:W与P差异不显著,沼液比例越高影响越大,P_(0)处理与W_(1)、W_(2)和P_(1)处理差异不显著,但显著高于W_(3)、W_(4)、P_(2)、P_(3)和P_(4)处理。在等浓度施用氮磷钾条件下,餐厨沼液滴灌水盐调控仍会增加土壤盐分,降低土壤铵态氮含量和西兰花产量,但在控制土壤盐分和增加餐厨沼液可施用比例方面,-20 kPa明显优于-30 kPa。

关键词：餐厨沼液滴灌沼液比例土壤水基质势西兰花产量土壤盐分无机氮

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石灰乳化学反应活性测定方法的创新与应用

化学工程师 2024年第6期38卷 105-109,113页

作者：田伟汪丽红刘召清李华浙江天石纳米科技股份有限公司浙江杭州311600 国际香精香料(杭州)有限公司浙江杭州311600 杭州市建德生态环境监测站浙江杭州311600

石灰乳活性的高低直接决定相关化学反应效率和效果。表征石灰乳活性的现有方法,在特定应用领域和场景下可以满足石灰乳优选,但都存在共性问题,即表征值与石灰乳化学反应之间没有直接逻辑关系,评价结果的准确性和有效性难以保证。为解决... 详细信息

石灰乳活性的高低直接决定相关化学反应效率和效果。表征石灰乳活性的现有方法,在特定应用领域和场景下可以满足石灰乳优选,但都存在共性问题,即表征值与石灰乳化学反应之间没有直接逻辑关系,评价结果的准确性和有效性难以保证。为解决这一问题,本文从石灰乳参与化学反应的过程机理入手,采用静态扩散——电导率曲线法测定石灰乳的化学反应活性。结果表明,该方法相较于现有方法,不仅能快速准确测量出石灰乳的化学反应活性,还可用于预测碳酸化反应时间以及轻质CaCO_(3)指标,为轻质CaCO_(3)生产工艺调节以及质量控制提供现实可靠的指导。

关键词：石灰乳化学反应活性静态扩散电导率曲线

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土壤优先流的理论研究和试验分析

环境科学学报 2009年第2期29卷 433-439页

作者：盛丰王康张仁铎李萼中山大学环境科学与工程学院武汉大学水资源与水电工程科学国家重点实验室

在活动流场模型的基础上建立了新的溶质运移控制方程,研究了流场分形特征参数的计算方法;采用4组染色示踪试验资料,分析了活动流场模型模拟土壤水流运动和溶质运移宏观非均匀特征的适用性.模拟分析表明,活动流场模型能较准确地捕捉到土... 详细信息

在活动流场模型的基础上建立了新的溶质运移控制方程,研究了流场分形特征参数的计算方法;采用4组染色示踪试验资料,分析了活动流场模型模拟土壤水流运动和溶质运移宏观非均匀特征的适用性.模拟分析表明,活动流场模型能较准确地捕捉到土壤中的优先流特别是不稳定流的宏观运动特征;土壤存在大孔隙结构的情况下,水流和溶质将更快的迁移到深层土壤,活动流场模型模拟计算的入渗深度偏小,但大于连续性模型的模拟计算结果;当土壤中的大孔隙结构较少时,活动流场模型模拟预测的土壤含水率分布和溶质浓度分布与实测结果比较一致.

关键词：活动流场模型分形本构关系溶质运移方程宏观非均匀性

氟西汀与Nrf2激活剂联合应用对蛛网膜下腔出血早期大鼠小胶质细胞炎症反应的抑制作用研究

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中国临床神经科学 2024年第3期32卷 260-267页

作者：张振中赵亮杨倩李丽宁衡水市第五人民医院衡水053000

目的探讨氟西汀与核因子-e2相关因子2(Nrf2)激活剂联合应用对蛛网膜下腔出血(SAH)早期大鼠小胶质细胞炎症反应的影响及其可能作用机制。方法选取30只雄性SD大鼠采用血管内穿刺法制备SAH模型,随机分为假手术组、SAH组、氟西汀组、Nrf2激... 详细信息

目的探讨氟西汀与核因子-e2相关因子2(Nrf2)激活剂联合应用对蛛网膜下腔出血(SAH)早期大鼠小胶质细胞炎症反应的影响及其可能作用机制。方法选取30只雄性SD大鼠采用血管内穿刺法制备SAH模型,随机分为假手术组、SAH组、氟西汀组、Nrf2激活剂(CDDO-eA)组、氟西汀+CDDO-eA组,每组n=6只。处理1 d后检测各组大鼠脑积水含量、Garcia评分。qRT-PCR法检测大脑皮质中iNOS、COX2 mRNA表达;eliSA法检测脑脊液中TNF-α、IL-6、IL-18水平;TUNeL法检测神经元凋亡情况;Western blot法检测Nrf2蛋白和小胶质细胞标记物CD11b蛋白表达、凋亡蛋白及Toll样受体4(TLR4)/P38丝裂原活化蛋白激酶(P38 MAPK)信号通路相关蛋白表达。结果与假手术组比较,SAH组Garcia评分降低,脑组织含水量、凋亡指数升高,CD11b、Bax、Cleaved-caspase-3、iNOS、COX2、TLR4、p-P38 MAPK表达量及TNF-α、IL-6、IL-18水平升高,Nrf2、Bcl-2表达量降低(均PeA组、氟西汀+CDDO-eA组的Garcia评分升高,脑组织含水量、凋亡指数降低,CD11b、iNOS、COX2、Bax、Cleaved-caspase-3、TLR4、p-P38 MAPK表达量及TNF-α、IL-6、IL-18水平降低,Nrf2、Bcl-2表达量升高,且氟西汀+CDDO-eA组变化幅度优于氟西汀组和CDDO-eA组(均P<0.05)。结论氟西汀与Nrf2激活剂联合治疗可抑制SAH后小胶质细胞活化、炎症反应,抑制神经元凋亡,减轻神经功能损伤,其机制可能与抑制TLR4/P38 MAPK信号通路活化有关。

关键词：蛛网膜下腔出血大鼠小胶质细胞氟西汀核因子-e2相关因子2 激活剂炎症反应

Context-Aware Recommendation System using Graph-based Behaviours Analysis

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Journal of Systems Science and Systems engineering 2021年第4期30卷 482-494页

作者： Lan Zhang Xiang li Weihua li Huali Zhou Quan Bai Auckland University of Technology AucklandNew Zealand University of Tasmania HobartAustralia

Recommendation systems have been extensively studied over the last decade in various domains. It has been considered a powerful tool for assisting business owners in promoting sales and helping users with decision-making when given numerous choices. In this paper, we propose a novel Graph-based Context-Aware Recommendation Systems with Knowledge Graph to analyse and predict users’ behaviours, i.e., making recommendations based on historical events and their implicit associations. The model incorporates contextual information extracted from both users’ historical behaviours and events relations, where the contexts have been modelled as knowledge graphs. By leveraging the advantages offered from the knowledge graph, events dependencies and their subtle relations can be established and have been introduced in the recommendation process. experimental results indicate that the proposed approach can outperform the state-of-the-art algorithms and achieve more accurate recommendations.

关键词： Contextual information extraction knowledge graph context-awareness recommendation system user behaviour analysis

Graph Convolutional Network Combined with Semantic Feature Guidance for Deep Clustering

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Tsinghua Science and Technology 2022年第5期27卷 855-868页

作者： Junfen Chen Jie Han Xiangjie Meng Yan li Haifeng li Key Laboratory of Machine Learning and Computational Intelligence of Hebei Province the College of Mathematics and Information ScienceHebei UniversityBaoding 071002China School of Applied Mathematics Beijing Normal University ZhuhaiZhuhai 519087China Department of Computer Teaching Hebei UniversityBaoding 071002China

The performances of semisupervised clustering for unlabeled data are often superior to those of unsupervised learning,which indicates that semantic information attached to clusters can significantly improve feature representation *** a graph convolutional network(GCN),each node contains information about itself and its neighbors that is beneficial to common and unique features among *** these findings,we propose a deep clustering method based on GCN and semantic feature guidance(GFDC) in which a deep convolutional network is used as a feature generator,and a GCN with a softmax layer performs clustering ***,the diversity and amount of input information are enhanced to generate highly useful representations for downstream ***,the topological graph is constructed to express the spatial relationship of *** a pair of datasets,feature correspondence constraints are used to regularize clustering loss,and clustering outputs are iteratively *** external evaluation indicators,i.e.,clustering accuracy,normalized mutual information,and the adjusted Rand index,and an internal indicator,i.e., the Davidson-Bouldin index(DBI),are employed to evaluate clustering *** results on eight public datasets show that the GFDC algorithm is significantly better than the majority of competitive clustering methods,i.e.,its clustering accuracy is20% higher than the best clustering method on the United States Postal Service *** GFDC algorithm also has the highest accuracy on the smaller Amazon and Caltech ***,DBI indicates the dispersion of cluster distribution and compactness within the cluster.

关键词： self-supervised clustering graph convolutional network feature correspondence semantic feature guidance confusion matrix evaluation indicator

石灰石粉掺量对混凝土中钢筋脱钝临界氯离子含量的影响

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材料导报 2024年第1期38卷 72-78页

作者：李辰治蒋林华同济大学土木工程学院上海200092 河海大学力学与材料学院南京210098

本工作研究了不同石灰石粉掺量(10%、20%、30%,质量分数,下同)对钢筋脱钝临界氯离子含量的影响,对混凝土试件进行干湿循环处理以加速氯离子渗透,同时采用半电池电位和电化学阻抗谱分别测定了钢筋的自腐蚀电位和腐蚀电流密度。结果表明,... 详细信息

本工作研究了不同石灰石粉掺量(10%、20%、30%,质量分数,下同)对钢筋脱钝临界氯离子含量的影响,对混凝土试件进行干湿循环处理以加速氯离子渗透,同时采用半电池电位和电化学阻抗谱分别测定了钢筋的自腐蚀电位和腐蚀电流密度。结果表明,临界氯离子含量随着石灰石粉掺量的增加而减小,这主要是因为石灰石粉的掺入导致水泥含量降低,从而使混凝土孔隙液pH值降低。XRD分析表明石灰石粉的掺入抑制了单硫型水化硫铝酸钙(AFm)相的生成,从而降低了水化产物的氯离子结合能力。腐蚀电流密度的变化趋势服从三参数Weibull分布,其概率密度可以表征钝化膜破裂的速率,随着石灰石粉掺量的增加,钝化膜破裂速率增加。

关键词：石灰石粉掺量临界氯离子含量腐蚀电位与电流密度钢筋脱钝 Weibull分布

Type Synthesis of Fully Decoupled Three Translational Parallel Mechanism with Closed-Loop Units and High Stifness

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Chinese Journal of Mechanical engineering 2023年第5期36卷 231-247页

作者： Shihua li Sen Wang Haoran li Yongjie Wang Shuang Chen Hebei Provincial Key Laboratory of Parallel Robot and Mechatronic Systems Yanshan UniversityQinhuangdao 066004China

In order to solve the problem of weak stifness of the existing fully decoupled parallel mechanism, a new synthesis method of fully decoupled three translational (3T) parallel mechanisms (PMs) with closed-loop units and high stifness is proposed based on screw theory. Firstly, a new criterion for the full decoupled of PMs is presented that the reciprocal product of the transmission wrench screw matrix and the output twist screw matrix of PMs is a diagonal matrix, and all elements on the main diagonal are nonzero constants. The forms of the transmission wrench screws are determined by the criterion. Secondly, the forms of the actuated and unactuated screws can be obtained according to their relationships with the transmission wrench screws. The basic decoupled limbs are generated by combination of the above actuated and unactuated screws. Finally, a closed-loop units construction method is investigated to apply the decoupled mechanisms in a better way on the high stifness occasion. The closed-loop units are constructed in the basic decoupled limbs to generate a high-stifness fully decoupled 3T PM. Kinematic and stifness analyses show that the Jacobian matrix is a diagonal matrix, and the stifness is obviously higher than that of the coupling mechanisms, which verifes the correctness of the proposed synthesis method. The mechanism synthesized by this method has a good application prospect in vehicle durability test platform.

关键词： Screw theory Three translational parallel mechanism Full decoupled Closed-loop units High stifness

Tunable Thermal Rectification and Negative Differential Thermal Resistance in Gas-Filled Nanostructure with Mechanically-Controllable Nanopillars

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Journal of Thermal Science 2022年第4期31卷 1084-1093页

作者： li Fan li Haiyang WANG Jun XIA Guodong HWANG Gisuk MOe Key Laboratory of enhanced Heat Transfer and energy Conservation Beijing Key Laboratory of Heat Transfer and Energy ConversionBeijing University of TechnologyBeijing 100124China Department of Mechanical engineering Wichita State University Wichita KS 67260USA

In this study,by using the nonequilibrium molecular dynamics and the kinetic theory,we examine the tailored nanoscale thermal transport via a gas-filled nanogap structure with mechanically-controllable nanopillars in one surface only,i.e.,changing nanopillar *** is found that both the thermal rectification and negative differential thermal resistance(NDTR)effects can be substantially enhanced by controlling the nanopillar *** maximum thermal rectification ratio can reach 340%and the△T range with NDTR can be significantly enlarged,which can be attributed to the tailored asymmetric thermal resistance via controlled adsorption in height-changing nanopillars,especially at a large temperature *** tunable thermal rectification and NDTR mechanisms provide insights for the design of thermal management systems.

关键词： thermal rectification negative differential thermal resistance kinetic theory nanopillars