摘要：Actinide-based catalysts have been regarded as promising candidates for N_(2) fixation owing to their unique 5f orbital with flexible oxidation ***,we report for the first time the dispersion of uranium(U)single atoms on TiO_(2) nanosheets via oxygen vacancy confinement for N_(2) *** single-atom U catalyst exhibited a high NH_(3) yield of 40.57μg h^(-1) mg^(-1),with a reasonably high Faraday efficiency of 25.77%,ranking first among the reported nitrogen-free ***-labeling operando synchrotron infrared spectroscopy verifies that the key*N_(2)H_(y) intermediate species was derived from the N_(2) gas of the *** using operando X-ray absorption spectroscopy,we found enhanced metal-support interaction between U single atoms and TiO_(2) lattice with more U-O_(latt) coordination under working *** simulations suggest that the evolved 1O_(ads)-U-4O_(latt) moieties act as a critical electronfeedback center,lowering the thermodynamic energy barrier for the N_(2) dissociation and the first hydrogenation *** work provides the possibility of tailoring the interaction between metal active sites and supports for designing high-performance actinide-based single-atom catalysts.

摘要：基于弹性支链并联机构的波浪能转换装置能够采集多方向不规则的波浪能,并且实现向机械能、电能的转换。装置结构参数设计是影响波能转换效率的主要因素之一。动平台在波浪力作用下存在空间位姿的不断变换,通过建立机构的运动学逆解模型,获得给定动平台位姿下弹簧支链的伸缩变形量。针对机构几何参数及支链弹簧物理参数对弹簧支链变形过程中弹性势能的影响,分别进行单参数试验设计及灵敏度分析,确立将支链弹簧系数、动静平台铰点分布角及分布圆半径、平台之间的高度等相关结构参数作为设计变量。进一步以机构运动过程中弹性支链的最大变形能作为优化目标,基于ADAMS/Insight构建多设计变量优化数学模型,通过求解获得机构最佳设计参数。研究结果对改进波能转换装置设计以及提升波浪能转换效率具有重要的意义。

摘要：Engineering the electronic properties of catalysts to target intermediate adsorption energy as well as harvest high selectivity represents a promising strategy to design advanced electrocatalysts for efficient CO_(2) ***,a synergistical tuning on the electronic structure of the Cd Se nanorods is proposed for boosting electrochemical reduction of CO_(2) .The synergy of Ag doping coupled with Se vacancies tuned the electronic structure of the CdSe nanorods,which shows the metalloid characterization and thereby the accelerated electron transfer of CO_(2) *** synchrotron radiation Fourier transform infrared spectroscopy and theoretical simulation revealed that the Ag doping and Se vacancies accelerated the CO_(2) activation process and lowered the energy barrier for the conversion from CO_(2) to;COOH;as a result,the performance of CO_(2) electroreduction was *** as-obtained metalloid Ag-doped CdSe nanorods exhibited a 2.7-fold increment in current density and 1.9-fold Faradaic efficiency of CO compared with the pristine CdSe nanorod.

摘要：The coverage of network resources is increasingly extensive,and computing resources have likewise gradually become fundamental infrastructures,providing ubiquitous computing ***,in wide area networks(WANs),the underlying network and computing resources are not closely investigated or co-designed,and there are still problems reflected in slow computing service scheduling,inflexible data distribution,and inefficient data transmission.

摘要：昆都仑河水库整个库坝区覆盖层皆为沙化盐碱地层,透水性、腐蚀性和盐胀性皆较强,且厚度大而难以换填,导致其成库论证及防渗处置极其复杂,而两者成功与否是水库修建的决定性因素。本文基于地质调查、地质钻探和室内外试验成果,探索沙化盐碱地岩土体物理及化学特性,以求为成库论证及防渗对策研究奠定基础。结果表明:库坝区上部地层皆为强透水性,存在库区、坝肩和坝基渗漏,不具备成库蓄水天然地质条件。库坝区表层厚度约2.0m为沙化盐碱土,具有较强的腐蚀性和盐胀性,但皆随埋深增加而逐渐变弱。坝基全—强风化泥岩皆呈弱透水性,防渗性较好,为天然库底隔水层,其抗压强度及坝基承载力皆随埋深增加和风化程度减弱逐渐提高。推荐库坝区采用砼防渗面板铺盖方案,且砼必须具备抗硫酸盐、高密实性、高强度等特性,且严控施工和养护质量,可实现成库蓄水。

摘要：针对黄花菜采摘点识别定位求解困难,开发了一款基于双目视觉系统的黄花菜采摘机器人,从确定并联机械手尺寸参数到对黄花菜图像采摘点定位求解进行了研究。提出一种在自然场景下黄花菜视觉识别与采摘点定位方法,对黄花菜图像提取HSI空间分量S并采用迭代最佳阈值分割算法;将黄花菜生长趋势姿态分为两类,计算连通域最小外接矩形,确定不同生长姿态下的感兴趣区域;在区域内运用累计概率霍夫直线检测结合求解对应参考点点线最小距离约束,取线段离矩形框参考点距离最小的端点为采摘点。以晴天顺光、晴天背光和阴天光照条件下进行实验验证,结果表明可以为采摘机器人提供黄花菜采摘点精确坐标信息。

摘要：立体种植装置是植物工厂领域常见的设施设备,层数较高的固定式立体种植装置往往会给种植栽培过程带来诸多麻烦且劳动效率较低,为改善这种现状,设计了一种床箱自走式立体智能种植装置。该装置主要由栽培架、栽培床箱升降装置、灌溉系统和控制系统组成,可自动实现栽培装箱的升降及推送过程,高效完成叶菜等作物的立体种植过程,叶菜年产量可达23万颗左右。该装置较大程度上解决了植物工厂领域层架栽培模式费时费力的问题,提高栽培效率,为立体种植装置的设计提供参考。

摘要：编队控制是多机器人系统研究的核心问题之一,具有广泛的研究价值。针对编队问题,通过对轮式差分驱动机器人运动模型进行分析,并设计相应的控制器。在传统的领航-跟随模型上,引入“虚拟机器人”,将跟随者机器人对领航者机器人的轨迹跟踪转换为跟随者对“虚拟领航者”的轨迹跟踪。首先,预设定实际领航者机器人的行进路径,由实际领航者引导运动方向的运动轨迹被视为主轨迹,虚拟机器人通过数据产生参考点从而生成参考轨迹,跟随者机器人通过对参考轨迹的跟踪与“虚拟领航者”构成轨迹误差跟踪系统。然后通过Lyapunov的控制理论验证控制器的理论可行性,最后在MATLAB/Simulink仿真平台进行实验,通过改变控制参数来使机器人形成相应的期望队形,在较短的时间内,跟随机器人对参考轨迹的跟踪误差趋向于0且速度收敛,验证了编队系统的可行性。

摘要：半封闭温室是近年来新兴温室,其中温室气候走廊和正压送风系统是半封闭温室的关键系统设计。通过对半封闭温室内夏季温度分布的均匀性和风道风速测试试验,验证温室的降温能力和送风系统性能。试验结果表明,SFG5-4型风机配套35 m长风道,送风相对均匀,风速4.3~4.7 m/s;对于温度分布规律来说,在同一水平方向上温室内各点的平均温差1.0~1.8℃,在同一高度方向上温室内各点的平均温差2.2~3.5℃,并且3.5 m湿帘比2.0 m湿帘降温效果好。

摘要：伴随着广告的普及,违法广告检测的意义重大。面对目前已有的违法广告检测方法仅能判断是否违法,而不能提取违法词并关联违法法条的问题,提出一种基于命名实体识别的违法广告词检测方法,此方法将触及违法条例关键词作为特殊的实体进行识别。具体包括以下步骤:使用BERT(bidirectional encoder representation from transformers)预训练模型提取动态字向量作为模型的输入,构建双向长短期记忆网络获取广告文本上下文的信息输出得分向量,最后结合条件随机场对标签进行限制,获取到最优标签。实验结果表明,这种基于命名实体识别的检测方法可有效地完成违法广告的检测,不仅可以提取违法词,而且还可识别出违法词触犯的相应法条。