基于改进鲸鱼算法的混合直流输电系统控制参数优化方法

混合直流输电系统结合了传统电网换相换流器和电压源换流器的优点，具有广泛的应用前景。为解决混合直流输电系统控制参数优化问题，引入一种新型的元启发式算法--鲸鱼算法。针对算法全局搜索能力较差的问题，引入混合优化理论，利用模拟退火和联赛选择机制对其进行了改进，改进算法有效平衡了全局搜索与局部开发能力，降低了对参数选择的依赖性。以双极型两端混合直流输电测试系统为研究对象，采用改进鲸鱼算法优化整流侧定电流控制中的比例积分（proportional integra，PI）参数和逆变侧dq轴双环控制器的PI参数，并通过MATLAB和PSCAD软件联合仿真实现该算法。算例结果表明，相比于原始鲸鱼算法和粒子群算法，所提算法具有更高收敛精度，有效优化了控制系统的参数，提升了混合直流输电系统的指令跟踪能力。     

^137Cs事故受照人员外周血淋巴细胞染色体畸变的随访观察

本文报道了３６例在５个月内多次受到＾１３７Ｃｓγ射线源照射受照人员的细胞遗传学随访观察结果。结果表明，在照后１年和５年，各类染色体型畸变明显高于对照组，差异显著或非常显著。由于非稳定性畸变的不断丢失。在照后５年，染色体畸变率比照后１年明显降低，但此时畸变细胞率和累积剂量之间仍存在正相关关系。     

Acid and Base Resistant Zirconium Polyphenolate‐Metalloporphyrin Scaffolds for Efficient CO2 Photoreduction

A series of zirconium polyphenolate‐decorated‐(metallo)porphyrin metal–organic frameworks (MOFs), ZrPP‐n (n = 1, 2), featuring infinite Zr^IV‐oxo chains linked via polyphenolate groups on four peripheries of eclipse‐arranged porphyrin macrocycles, are successfully constructed through a top–down process from simulation to synthesis. These are the unusual examples of Zr‐MOFs (or MOFs in general) based on phenolic porphyrins, instead of commonly known carboxylate‐based types. Representative ZrPP‐1 not only exhibits strong acid resistance (pH = 1, HCl) but also remains intact even when immersed in saturated NaOH solution (≈20 m ), an exceptionally large range of pH resistance among MOFs. The metallation at the porphyrin core gives rise to materials with enhanced sorption and catalytic properties. In particular, ZrPP‐1‐Co, with precise and uniform distribution of active centers, exhibits not only high CO₂ trapping capability (≈90 cm³ g^?1 at 1 atm, 273 K, among the highest in Zr‐MOFs) but also high photocatalytic activity for reduction of CO₂ into CO (≈14 mmol g^?1 h^?1) and high selectivity over CH₄ (>96.4%) without any cocatalyst under visible‐light irradiation (λ > 420 nm). Given the strong chemical resistance under extreme alkali conditions, these catalysts can be recycled without appreciable loss of activity. The possible mechanism for photocatalytic reduction of CO₂‐to‐CO over ZrPP‐1‐Co is also proposed.     

浅谈合同能源管理模式在通信行业中的应用

介绍了合同能源管理模式及节能量的分析与验证,分析了通信行业合同能源管理模式的应用、存在问题和主要风险评估,提出了通信行业合同能源管理模式的发展趋势。     

选区激光熔化成形TC4钛合金力学性能及其工艺关联性EI北大核心CSCD

增材制造技术可实现复杂结构的无模具,快速、近净成形,高致密度。为保证零件的成形质量,建立金属增材制造技术工艺参数—微观结构—宏观力学性能的关联机制十分关键。采用选区激光熔化技术(SLM)制备四种不同工艺参数组合的Ti-6Al-4V合金(又称TC4),对比和讨论试件微观形貌。通过单轴拉伸试验从宏观角度研究准静态条件下材料本构行为,并确定流动应力和应变极限等关键力学性能参数,通过纳米压痕试验从微观角度研究0.01/s和0.10/s压痕应变率下材料荷载-位移曲线,并基于连续刚度法获取材料弹性模量和硬度。最后通过引入约束因子和位错密度,结合单轴拉伸和纳米压痕试验所得的力学性能,讨论SLM成形过程中激光能量输入密度对TC4材料宏观力学性能的影响规律。通过开展工艺参数与力学性能的相关性分析,从更具统计意义的角度阐明SLM工艺参数—微观结构—宏观力学性能的关联机制,进而更加有效地确定可用于调控SLM成形TC4材料宏观力学性能的工艺参数优化组合。研究结果可为提升TC4材料力学性能的SLM成形工艺参数提供指导。     

细胞培养肉支架材料与组织成型研究进展

细胞培养肉技术是近年来兴起的一项颠覆性食品制造技术,旨在建立人类的肉蛋白食物生产与供给新模式,缓解传统畜牧业的可持续性生产压力和环境保护问题。本文聚焦细胞培养肉支架材料及其组织成型进展,从细胞感知与三维培养、生物培养支架材料筛选及细胞组织成型构建等3个方面综述组织化培养肉支架相关的主要技术与方法,并对培养肉质构研究现状与存在问题进行分析,旨在为细胞培养肉技术开发与高质量发展提供思路。     

Growth of continuous GaN films on ZnO buffer layer by chemical vapor deposition for ultraviolet photodetector

In this work, c-axis-oriented continuous GaN films have been synthesized by the chemical vapor deposition (CVD) method using ZnO material as the intermediate buffer layer. The GaN films with different growth temperatures exhibit high crystal quality and small surface roughness due to the same crystal structure and low lattice mismatches rate between GaN and ZnO materials. Meanwhile, the UV photodetector based on the CVD-grown GaN film exhibits a relatively high responsivity, fast rise and decay time, and good thermal stability. Our work provides a simple and promising CVD method to fabricate continuous GaN film for electronic and optoelectronic devices.

     

浅谈通信机房灰尘的限制要求

介绍了灰尘对通信设备中电子产品的影响,及国内外通信行业标准对灰尘的限制要求,提出防止灰尘进入通信机房的措施。     

SZ—4水环泵断轴的原因及解决办法

针对聚氯乙烯分厂ＳＺ－４水环泵曾一度出现的泵轴断裂频繁问题。分析了断轴的原因，并提出了解决的办法。