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频率分集阵列；子阵频率分集阵列；解耦；点状波束形成 1

频率分集阵列；欺骗干扰；距离角度耦合；和差波束；双波束 1

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Regulatory issues for genetically modified animals

Perry Bradbury HACKETT

《农业科学与工程前沿（英文）》 2020年第7卷第2期页码 188-203 doi: 10.15302/J-FASE-2019307

摘要：

Precision genetics and breeding have the potential to meet the agricultural needs and goals of the world in the 21st century. These needs include increasing the efficiency of production of animals and improving their products with minimal impact on the environment. The USA is the major innovator in genomic science and the acknowledged leader in formulating policies to regulate genetic applications in medicine and agriculture. However, governments worldwide have been exceedingly reluctant to support the introduction of genetically modified (GM) animals into agriculture. Regulatory policies have stagnated due to legal guidelines that could not anticipate the needs and solutions that are evident today. This must change if we are to maintain planetary integrity. I propose a new, market-based regulatory model for GM livestock that has both a strong scientific foundation and has worked for 10000 years. The model is similar to that for information technology in which specific algorithms drive computer and cell phone applications. Genome engineers write genetic algorithms that drive the traits in biological organisms. Accordingly, GM products should be viewed in terms of their use and public benefit rather than by limitations to the genetic programing coming from a few highly vocal groups. Genetic algorithms (Genapps) of the 21st century will include not only introduction of synthetic genes, but also complete natural and synthetic biochemical pathways to produce agricultural products that are maximally efficient, healthy to humans and animals, and sustainable in an era of changing climates while avoiding environmental degradation.

关键词： algorithms editing FDA GMO recombinant DNA USDA

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基于子阵sin-FDA的点状波束形成研究 Research Article

Bo Wang, Jun-wei Xie, Jing Zhang, Jia-ang Ge,wb_wangbo1991@163.com

《信息与电子工程前沿（英文）》 2019年第20卷第10期页码 1429-1444 doi: 10.1631/FITEE.1800722

摘要：与PA相比，频率分集阵列（frequency diverse array，FDA）时间—距离—角度相关的波束特性，使其在抑制距离维相关干扰方面具有巨大潜力。但是，FDA发射波束方向图中固有的距离角耦合会降低输出信干噪比（signal-to-interference-plus-noise ratio，SINR）。基于对4种采用正弦频控函数发射多载频的子阵FDA及平面FDA的分析，提出一种点状波束形成方法。数值结果表明，该方法在传输能量聚焦、旁瓣抑制和阵列分辨率上优于现有的log-FDA。

关键词：频率分集阵列；子阵频率分集阵列；解耦；点状波束形成

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基于距离、角度定位的频率分集阵列欺骗干扰鉴别方法 Article

Zhao-jian ZHANG, Jun-wei XIE, Chuan SHENG, Zhun TANG

《信息与电子工程前沿（英文）》 2017年第18卷第9期页码 1437-1446 doi: 10.1631/FITEE.1601577

摘要：针对电子对抗中的欺骗干扰鉴别问题，提出了基于频率分集阵列（frequency diverse array, FDA）的干扰鉴别方法。FDA波束具有距离—角度二维耦合特性，当波束聚焦距离与真实目标不一致时，会产生角误差信号，即干扰角度在相控阵中与真实目标一致，而在FDA中与真实目标不一致。因此，利用相控阵和FDA分别进行参数测量，比对测量结果即可实现干扰鉴别。提出了基于FDA进行干扰鉴别的具体流程，给出了两种双波束测量的实现方案，并对各方案的目标检测及参数估计性能进行了理论分析。

关键词：频率分集阵列；欺骗干扰；距离角度耦合；和差波束；双波束

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Molecular level understanding of CO₂ capture in ionic liquid/polyimide composite membrane

Linlin You, Yandong Guo, Yanjing He, Feng Huo, Shaojuan Zeng, Chunshan Li, Xiangping Zhang, Xiaochun Zhang

《化学科学与工程前沿（英文）》 2022年第16卷第2期页码 141-151 doi: 10.1007/s11705-020-2009-7

摘要： Ionic liquid (IL)/polyimide (PI) composite membranes demonstrate promise for use in CO separation applications. However, few studies have focused on the microscopic mechanism of CO in these composite systems, which is important information for designing new membranes. In this work, a series of systems of CO in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide composited with 4,4-(hexafluoroisopropylidene) diphthalic anhydride (6FDA)-based PI, 6FDA-2,3,5,6-tetramethyl-1,4-phenylene-diamine, at different IL concentrations were investigated by all-atom molecular dynamics simulation. The formation of IL regions in PI was found, and the IL regions gradually became continuous channels with increasing IL concentrations. The analysis of the radial distribution functions and hydrogen bond numbers demonstrated that PI had a stronger interaction with cations than anions. However, the hydrogen bonds among PI chains were destroyed by the addition of IL, which was favorable for transporting CO . Furthermore, the self-diffusion coefficient and free energy barrier suggested that the diffusion coefficient of CO decreased with increasing IL concentrations up to 35 wt-% due to the decrease of the fractional free volume of the composite membrane. However, the CO self-diffusion coefficients increased when the IL contents were higher than 35 wt-%, which was attributed to the formation of continuous IL domain that benefitted the transportation of CO .

关键词： carbon dioxide ionic liquid 6FDA-TeMPD composite membrane molecular dynamics simulation