任意拓扑野战分组交换网的性能分析

本文提出了一种用于快速计算野战分组交换网性能的方法。这种具有一般性的方法，适用于任意拓扑的野战分组交换网络，克服了只能计算某种规则网络性能的方法的局限性，大量的计算机仿真结果证实了这种分析方法的可行性和有效性。     

一种基于历史监测数据的谐波污染主特征群筛选方法

对谐波污染用户的耦合模型需要考虑不同次数谐波之间的相互影响,这将使得模型非常复杂,从而无法基于在线监测辨识模型参数建模。本文提出一种基于历史监测数据的谐波主特征量筛选方法,首先利用统计分析中常用的主成分分析(principle component analysis,PCA)方法,通过主成分和原始变量之间的相关系数计算谐波特征群指标;然后根据该指标历史监测数据中提取能够用于谐波分析的谐波污染主特征群;最后,以宁德市配电网采集的电能质量监测数据为例进行分析,验证所提出方法的可行性。     

大规模输配一体化系统牛顿法潮流计算性能分析及改进方法

为满足输配电网一体化潮流计算精度和计算速度需求,提出了一种改进的牛顿法潮流计算方法。针对输配电网一体化牛顿法雅可比矩阵病态严重、收敛性能较差等问题,采用自适应Levenberg-Marquardt算法初始精度提升速度快的特征选取初值、不完全三角分解法预处理雅可比矩阵,有效地保证了数值稳定性,提高了牛顿法的收敛性能。针对输配电网一体化后规模庞大、计算效率低等问题,利用图形处理器并行加速技术对算法中的一些计算量密集的步骤,包括雅可比矩阵的生成、矩阵—向量运算等进行加速处理。算例测试表明,该算法能够显著提高大规模输配电网一体化潮流计算的速度和精度,对于多配电网区域、环网、分布式电源、病态系统等多种情形具有较强的普适性。     

Dual mesoporous carbon with high nitrogen doping level as an efficient electrode material for supercapacitors

This paper reports a dual mesoporous carbon (NDMC) with high nitrogen doping level derived from the amino production of the sucrose synthesized under hydrothermal condition. The S _BET and total pore volume of the reported materials reaches up to 1101 and 1.67 cm³ g^?1, the small mesopores center at about 3.22–3.31 nm while the larger mesopores locate at 8.98–12.58 nm. The doping content of the nitrogen heteroatoms is found to be more than 11.6 at.%, and depend on the carbonization temperature. The maximum specific capacitance of the reported materials reaches up to 512 F g^?1 due to the additional contribution of pseudo-capacitance induced by the nitrogen heteroatoms doping. The capacitance retention rate is found to be up to 95% after 1000 times cycles. The dual mesoporous structure, high specific area, additional pseudo-capacitance, enhanced wettability and conductivity are found to response for the superior capacitance performance of the reported materials.     

A High‐Performance Sodium‐Ion Hybrid Capacitor Constructed by Metal–Organic Framework–Derived Anode and Cathode Materials

Sodium‐ion hybrid capacitors (SIHCs) can potentially combine the virtues of high‐energy density of batteries and high‐power output as well as long cycle life of capacitors in one device. The key point of constructing a high‐performance SIHC is to couple appropriate anode and cathode materials, which can well match in capacity and kinetics behavior simultaneously. In this work, a novel SIHC, coupling a titanium dioxide/carbon nanocomposite (TiO₂/C) anode with a 3D nanoporous carbon cathode, which are both prepared from metal–organic frameworks (MOFs, MIL‐125 (Ti) and ZIF‐8, respectively), is designed and fabricated. The robust architecture and extrinsic pseudocapacitance of TiO₂/C nanocomposite contribute to the excellent cyclic stability and rate capability in half‐cell. Hierarchical 3D nanoporous carbon displays superior capacity and rate performance. Benefiting from the merits of structures and performances of anode and cathode materials, the as‐built SIHC achieves a high energy density of 142.7 W h kg^?1 and a high power output of 25 kW kg^?1 within 1–4 V, as well as an outstanding life span of 10 000 cycles with over 90% of the capacity retention. The results make it competitive in high energy and power–required electricity storage applications.     

通信系统抗干扰性能的灰色聚类分析

本文采用灰色系统理论分析通信系统的抗干扰性能。首先讨论了通信系统抗干扰性能的参数模型,接着提出了抗干扰性能的分析算法,具有较强的有产性和通用性。最后给出了抗干扰性能的分析范例。     

Gas desorption properties of TiC/C compositionally graded coatings on doped graphite

To mitigate carbon contamination from doped graphite (1% B, 2.5% Si, 7.5% Ti) by irradiation of plasma, TiC/C compositionally graded coatings (CGCs) were prepared by chemical vapor deposition. Scanning electron microscopy (SEM) results indicated that the TiC/C CGCs were characterized by avoidances of cracks and loosely bonded particles. Gas desorption results suggested that out gas amount increased with the increase of temperatures. However, it was much lower than that of pure TiC coatings after irradiation for 300 s.     

漂烫温度与干燥仓压力对豆丹真空冷冻干燥品质的影响

为了使豆丹在真空冷冻干燥后获得较高的品质,以干燥成功率、干燥时间、蛋白质保留率、色泽变化、复水率为衡量指标,确定豆丹的漂烫温度和干燥仓压力两个重要参数。试验以差示扫描量热法确定了豆丹共晶点为-19.9℃,以此确定豆丹的预冻温度为-28℃。结果表明,漂烫温度为60℃时干燥成功率可以高达97%,蛋白质保留率分别在漂烫温度为50℃和80℃时达到最高和最低。随着干燥室压力的减小,蛋白质保留率有减小的趋势。干燥仓压力对豆丹的色泽影响比较小。干燥仓压力为57 Pa、漂烫温度为60℃时干燥效果最佳,复水率最高。     

有机胺萃取耦合CO2矿化过程中阴离子迁移规律研究

目的 CO₂矿化技术利用金属离子将CO₂固化为碳酸盐是有效的碳减排路径,考查有机胺萃取耦合CO₂矿化过程中阴离子的迁移规律,为进一步设计矿化过程提供理论参考。方法 有机胺萃取耦合CO₂矿化法利用有机胺萃取氢离子(H⁺),并使阴离子迁移到有机相中,促进水相的钙、镁等金属离子进一步与碳酸根离子(CO₃^2-)沉淀,测定镁基、钙基体系中CO₂矿化反应后阴离子的浓度和迁移率,并考查了时间、温度、相比(有机相与水相的体积比)对迁移率的影响。结果 镁基体系中,阴离子迁移率y_I^->y_NO^-3>y_Br^->y_Cl^->y₍SO^2-₄);钙基体系中,阴离...     

酶联免疫吸附法检测动物源性食品中恩诺沙星残留量

为检测动物源性食品中恩诺沙星残留量,评估基于卵黄抗体的间接竞争酶联免疫吸附法检测恩诺沙星的可行性,用活性脂法将恩诺沙星同卵清蛋白偶联制备免疫原和包被抗原并用紫外光谱进行验证。用聚乙二醇-6000提取卵黄抗体。五免之后效价达到峰值1∶32 000。用间接竞争酶联免疫吸附法确定包被原质量浓度、卵黄抗体的稀释倍数和IC_(50)分别为38 ng/m L、1∶64 000和18.207 ng/m L,回归曲线方程为y=0.891 1-0.016 5x(R~2=0.990)。结果表明,制备的抗恩诺沙星卵黄抗体为进一步建立检测动物源性食品中恩诺沙星的残留的免疫方法提供参考依据。