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基于级数反演的星弹双基俯冲前视成像算法

中国空间科学技术 2024年第1期44卷 135-143页

作者：席子瑞段崇棣左伟华李财品李东涛空间电子信息技术研究院西安710000

由于导弹在俯冲阶段存在垂直向加速度,速度的大小和方向在不断变化,弹头沿曲线运动,导致瞬时斜距十分复杂,造成严重的距离徙动现象,方位向和距离向存在严重的二维耦合问题。针对此问题提出了一种基于级数反演的星弹双基俯冲前视成像算... 详细信息

由于导弹在俯冲阶段存在垂直向加速度,速度的大小和方向在不断变化,弹头沿曲线运动,导致瞬时斜距十分复杂,造成严重的距离徙动现象,方位向和距离向存在严重的二维耦合问题。针对此问题提出了一种基于级数反演的星弹双基俯冲前视成像算法。该算法根据星弹双基系统特性,搭建了星弹双基轨迹模型,在距离频域方位时域进行多普勒频率校正,再利用级数反演的思想,推导出回波信号的二维频谱表达式,接着在二维频域上进行距离徙动校正和距离向、方位向压缩,确定目标成像位置,完成成像聚焦。最后通过计算量的分析和仿真验证了算法的可行性和有效性。该算法可实现对多目标的探测和区分,对军方察打一体化研究具有理论指导意义,对中国军事行动方面具有一定价值。

关键词：星弹双基俯冲前视成像距离徙动校正级数反演多普勒频率校正

改进的NLCS星弹双基SAR俯冲前视成像算法

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电讯技术 2024年第1期64卷 51-57页

作者：席子瑞段崇棣左伟华李财品李东涛空间电子信息技术研究院西安710100

在俯冲阶段由于导弹具有加速度,速度大小和方向会发生急剧变化,其收发瞬时斜距会变复杂,将导致距离-方位向耦合严重和方位空变性问题,若直接进行方位向聚焦压缩,会造成图像畸变。针对这两个难题,采用一种改进的非线性变标(Nonlinear Chi... 详细信息

在俯冲阶段由于导弹具有加速度,速度大小和方向会发生急剧变化,其收发瞬时斜距会变复杂,将导致距离-方位向耦合严重和方位空变性问题,若直接进行方位向聚焦压缩,会造成图像畸变。针对这两个难题,采用一种改进的非线性变标(Nonlinear Chirp Scaling,NLCS)算法运用到新型星弹双基系统模型中。首先建立了星弹双基系统模型;接着利用级数反演法推导了二维频谱表达式,在二维频域中通过完成距离压缩和徙动校正来消除距离-方位耦合的影响,再利用改进的NLCS算法对方位向多普勒调频率进行补偿解决方位向空变性问题,完成方位向压缩聚焦,从而得到良好的成像结果。与改进的距离多普勒(Range Doppler,RD)算法相比,该算法减少了1.013×10^(8)浮点运算量(Floating Point Operations per Second,FLOPS),边缘点方位向聚焦效果有了很大的改善,方位向峰值旁瓣比(Peak Sidelobe Ratio,PSLR)、积分旁瓣比(Integrated Sidelobe Ratio,ISLR)、分辨率分别提升了2.41 dB,1.29 dB,1.16 m,证明了该方法的有效性与可行性。

关键词：星弹双基SAR 前视成像非线性变标算法级数反演

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泡沫凝胶稳定性及其结构演化特征研究

中国矿业 2024年第5期33卷 205-210页

作者：李小超秦剑云余小华李东涛尚学锋任万兴贾慧霖库车县榆树岭煤矿有限责任公司新疆库车842000 中国矿业大学安全工程学院江苏徐州221116

泡沫凝胶是一种高效的煤自燃防治材料,该材料结合了泡沫的流动性和堆积性、凝胶的耐温性等防灭火特性。本文从泡沫凝胶的形成原理、结构演化、稳定性和流动性等阐述了泡沫凝胶的防灭火特征。泡沫凝胶主要由发泡剂、交联剂和水等通过物... 详细信息

泡沫凝胶是一种高效的煤自燃防治材料,该材料结合了泡沫的流动性和堆积性、凝胶的耐温性等防灭火特性。本文从泡沫凝胶的形成原理、结构演化、稳定性和流动性等阐述了泡沫凝胶的防灭火特征。泡沫凝胶主要由发泡剂、交联剂和水等通过物理发泡和成胶反应后形成,其形成过程分为两个阶段:第一阶段为物理发泡,形成泡沫液;第二阶段将交联剂加入泡沫,通过胶凝反应后生成泡沫凝胶。第一阶段泡沫凝胶主要体现泡沫的流动性和堆积性,第二阶段随着胶体量的增加,泡沫凝胶体现胶体的耐温性,同时可通过交联剂的添加量控制凝胶的成胶时间。泡沫凝胶的基础结构与水基泡沫的结构相同,不同的是凝胶颗粒构成了泡沫凝胶的基础骨架,减缓了重力排液和泡沫歧化速率。泡沫凝胶结构的演化过程包括液膜破裂、成胶和骨架坍塌等,最终形成凝胶层充填遗煤裂隙。泡沫凝胶在采空区中的流动受注浆压力、重力和阻力的综合作用,横向流动速度大于纵向流动速度,其扩散前峰轮廓线为椭球形。本文研究成果为泡沫凝胶的科学应用提供了有力支撑。

关键词：煤自燃稳定性泡沫凝胶结构演化胶凝反应

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配煤结构与炼焦升温程序对焦炭质量的影响

燃料与化工 2024年第3期55卷 32-35,39页

作者：刘洋李东涛代鑫郭德英赵鹏首钢集团有限公司技术研究院北京100043 绿色可循环钢铁流程北京市重点试验室北京100043

在保持其他因素不变的情况下,将配煤结构和炼焦升温程序2个因素结合起来,设计了3组配煤与3组炼焦升温程序组合的9个方案进行40 kg试验焦炉炼焦试验研究。结果表明:不同的配煤方案采用相同的升温程序,所得焦炭的冷强度、热强度、平均粒... 详细信息

在保持其他因素不变的情况下,将配煤结构和炼焦升温程序2个因素结合起来,设计了3组配煤与3组炼焦升温程序组合的9个方案进行40 kg试验焦炉炼焦试验研究。结果表明:不同的配煤方案采用相同的升温程序,所得焦炭的冷强度、热强度、平均粒度及显微结构组成不同,配煤质量好时,所得的焦炭质量也更优;同一配煤方案采用不同的升温程序,所得焦炭的冷热强度、平均粒度及显微组成不同;按恒温1000℃炼焦,虽然所得焦炭的抗碎强度M_(40)和平均粒度较低,耐磨强度M_(10)变化不大,但其热强度好,各向异性组分含量较高;随着煤样炼焦升温速度的提高,所得焦炭的平均粒度呈降低趋势;此外,采用适宜的炼焦升温程序,即使配煤结构差些,也可以得到质量较好的焦炭。

关键词：配煤结构炼焦升温程序焦炭质量冷强度热强度显微结构

The etching strategy of zinc anode to enable high performance zinc-ion batteries

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Journal of Energy Chemistry 2024年第1期88卷 125-143,I0004页

作者： Xueqing Fu Gaopeng li Xinlu Wang Jinxian Wang Wensheng Yu Xiangting Dong dongtao liu School of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130022JilinChina Department of Chemistry Northeast Normal UniversityChangchun 130024JilinChina

Zinc-ion batteries(ZIBs)are considered to be one of the most promising candidates to replace lithium-ion batteries(liBs)due to the high theoretical capacity,low cost and intrinsic ***,zinc dendrites,hydrogen evolution reaction,surface passivation and other side reactions will inevitably occur during the charging and discharging process of Zn anode,which will seriously affect the cycle stability of the battery and hinder its practical *** etching strategy of Zn anode has attracted wide attention because of its simple operation and broad commercial prospects,and the etched Zn anode can effectively improve its electrochemical ***,there is no comprehensive review of the etching strategy of Zn *** review first summarizes the challenges faced by Zn anode,then puts forward the etching mechanisms and properties of acid,salt and other ***,based on the above discussion,the challenges and opportunities of Zn anode etching strategy are proposed.

关键词： Zinc-ion batteries Zn anode Etching 3D structures Dendrite-free

The application of molecular simulation in ash chemistry of coal

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Chinese Journal of Chemical Engineering 2020年第11期28卷 2723-2732页

作者： Xin Dai Jin Bai Ping Yuan Shiyu Du dongtao li XiaodongWen Wen li Beijing Key Laboratory of Green Recyclable Process for Iron&Steel Production Technology Beijing 100043China Shougang Group Research Institute of Technology Beijing 100043China State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China Shanxi Research Institute for Clean Energy Tsinghua UniversityTaiyuan 030032China Engineering Laboratory of Specialty Fibers and Nuclear Materials Institute ofMaterial TechnologiesNingbo Institute ofMaterials Technology&EngineeringChinese Academy of SciencesNingbo 315000China

One of the crucial issues in modern ash chemistry is the realization of efficient and clean coal ***,large-scale coal gasification technology is well known as the foundation to improve the atom *** practice,the coal ash fusibility is a critical factor to determine steady operation standards of the gasifier,which is also the significant criterion to coal species selection for *** coal behaviors are resultant from various evolutions in different scales,the multi-scale understanding of the ash chemistry is of significance to guide the fusibility adjustment for coal *** important roles of molecular simulation in exploring ash chemistry,this paper reviews the recent studies and developments on modeling of molecular systems for fusibility related ash chemistry for the first *** discussions are emphasized on those performed by quantum mechanics and molecular mechanics,the two major simulation methods for microscopic systems,which may provide various insights into fusibility *** review article is expected to present comprehensive information for recent molecular simulations of coal chemistry so that new clues to find strategies controlling the ash fusion behavior can be obtained.

关键词： Coal ash Fusibility Molecular simulation Quantum mechanics Ash fusion temperature Viscosity

Oral pyroptosis nanoinhibitor for the treatment of inflammatory bowel disease

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Nano Research 2024年第3期17卷 1748-1759页

作者： Zhenxing Zhu dongtao Zhou Yi Yin Zhun li Zhen Guo Yongchun Pan Yanfeng Gao Jingjing Yang Weiming Zhu Yujun Song Yi li Department of General Surgery Affiliated Jinling HospitalMedical SchoolNanjing UniversityNanjing 210093China College of Engineering and Applied Sciences State Key Laboratory of Analytical Chemistry for Life ScienceNanjing UniversityNanjing 210023China Department of General Surgery Affiliated Drum Tower HospitalMedical SchoolNanjing UniversityNanjing 210008China Department of Biochemistry and Molecular Biology School of Medicine&Holistic Integrative MedicineJiangsu Collaborative Innovation Center of Chinese Medicinal Resources IndustrializationNanjing University of Chinese MedicineNanjing 210023China

Inflammatory bowel disease(IBD)is an autoimmune gastrointestinal disease characterized by chronic relapsing inflammation of the *** pyroptosis that exists in the inflamed intestine can activate damage signals and aggravate local inflammation in ***,we designed an oral pyroptosis nanoinhibitor,DXMS@CuM@PPADT@PSS(DCMP),which can target intestinal lesions,and respond to reactive oxygen species(ROS)to release active sites and drugs at the *** can inhibit the activation of the nucleotide-binding domain and leucine-rich repeat family pyrin domain containing 3(NLRP3)inflammasomes by scavenging ROS,resulting in the down-regulation of gasdermin D(GSDMD)cleavage thus inhibiting *** also improved intestinal barrier function,decreased inflammatory cytokine levels,and increased the diversity of gut microbiota in mice with *** work is believed to expand the biomedical application of nanomaterials for innate immunity modulation.

关键词： inflammatory bowel disease nanoinhibitors pyroptosis synergistic therapy antioxidant

First Discovery of Gold Ore Bodies in the lieryu Formation of the liaohe Group in the liaodong Area, China

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2342-2343页

作者： ZHANG Peng SHAO Jun li dongtao ZHAO Yan KOU linlin BI Zhongwei Shenyang Institute of Geology and Mineral Resources Shenyang Center of geological SurveyChina Geological Survey

Objective Numerous large deposits magnesite, and talc are liaodong area, within of lead-zinc, gold, boron, distributed throughout the different layers of the Paleoproterozoic liaohe Group. The liaohe Group comprises five formations as follows （from bottom to top）. The Langzishan Formation consists of volcaniclastic rocks containing copper, cobalt, and iron deposits. The lieryu Formation is a set of volcanic sedimentary facies accompanied by small amounts of continental-margin mixed volcanic sedimentary rocks containing boron and magnetite deposits. The Gaojiayu Formation consists of carbonaceous clay-bearing carbonate rocks and contains the most important graphite deposit. The Dashiqao Formation consists of carbonate rocks containing lead-zinc and magnesite deposits. The Gaixian Formation comprises clastic and volcaniclastic rocks, and contains the most important gold deposit. Historically, gold prospecting has focused on the Gaixian Formation; however, gold ore bodies have been discovered during iron ore mining in the lieryu Formation （Dayinggou area）, indicating possible existence of larger gold deposits in the area.

关键词： First Discovery of Gold Formation of the liaohe

Zircon U-Pb Ages of Tonalite in Faku,liaoning Province,China,and the Early Paleozoic Magmatic Activity in the North Margin of the North China Craton

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Acta Geologica Sinica(English Edition) 2019年第2期93卷 489-490页

作者： SHI Yiu ZHANG Zhibin YANG Fan li dongtao SHI Shaoshan ZHAO Chunqiang YOU Hongxi Shenyang Institute of Geology and Mineral Resources China Geological Survey College of Earth Sciences Jilin University

Objective Due to the Meso-Cenozoic Songliao Basin coverage,the Early Paleozoic continental-margin accretionary belt has not been detected in the middle of the north margin of the North China Craton (liu et al., 2017a,... 详细信息

关键词： Pb SHRIMP Magmatic Activity