组合Fenton法处理弹药销毁废水

采用Fenton氧化-活性炭吸附的组合工艺处理兰州军区某弹药试验站弹药销毁废水,通过现场的中试试验,系统考察了4个主要影响因子:H2O2浓度、Fe2+浓度、pH值及反应时间在Fenton氧化中对弹药销毁废水处理效率的影响,分析了各影响因子的作用机制,并确定了它们的最佳运行参数,即H2O2的浓度为0.1 mol/L,Fe2+的浓度为1.8 mmol/L,pH值为3.5,反应时间为8 h。结果表明这些因子对弹药销毁废水的处理效率均有较大影响,应严格控制。经组合Fenton法处理后,TNT、COD的质量浓度分别小于1、60 mg/L,色度小于5倍,达到了GB14470.3-2002标准中规定的污染物排放标准。     

Nested relation extraction with iterative neural network

Most existing researches on relation extraction focus on binary flat relations like BornIn relation between a Person and a Location. But a large portion of objective facts described in natural language are complex, especially in professional documents in fields such as finance and biomedicine that require precise expressions. For example, “the GDP of the United States in 2018 grew 2.9% compared with 2017” describes a growth rate relation between two other relations about the economic index, which is beyond the expressive power of binary flat relations. Thus, we propose the nested relation extraction problem and formulate it as a directed acyclic graph (DAG) structure extraction problem. Then, we propose a solution using the Iterative Neural Network which extracts relations layer by layer. The proposed solution achieves 78.98 and 97.89 F1 scores on two nested relation extraction tasks, namely semantic cause-and-effect relation extraction and formula extraction. Furthermore, we observe that nested relations are usually expressed in long sentences where entities are mentioned repetitively, which makes the annotation difficult and errorprone. Hence, we extend our model to incorporate a mentioninsensitive mode that only requires annotations of relations on entity concepts (instead of exact mentions) while preserving most of its performance. Our mention-insensitive model performs better than the mention sensitive model when the random level in mention selection is higher than 0.3.     

水下火箭弹头部空化流场的数值仿真研究

对火箭弹头部的局部空化流场的研究可作为头部敏感装置安装位置设计和选择的依据。研究了利用RANS(针对定常分析)和LES(针对非定常分析)湍流模型对水下火箭弹弹体头部空化流场进行仿真分析的方法,并与实验结果进行对比验证。通过仿真分析了在零攻角/小攻角下弹体头部周围定常、非定常流场空化区域和不同速度、加速度下空化区的变化;比较了相同空化数下不同速度对空化区域的影响。结果发现,小攻角情况下的火箭弹头部背流面空化流场存在较强的非定常特性,头部流场空化区受到加速度的影响且存在速度比尺效应。     

提高中大口径杀爆弹威力的技术途径

为研究提高中大口径杀爆弹威力的技术途径,分析了国内外弹药战斗部技术发展现状,通过几种炸药(及装药方式)与弹体材料及其性能匹配研究,杀伤威力的理论计算,结合某产品进行杀伤威力数值模拟和试验研究,提出提高中大口径杀爆弹威力的技术途径与建议。     

网络环境下不敏感系统的分布式区域预测控制方法

针对二分图网络结构下的不敏感系统的可控性比较差的问题,本文提出了带有区域控制的分布式模型预测控制方法.该方法首先利用分支定界法对分布式控制系统结构进行最优设计;然后,结合区域控制提高控制系统的动态性能指标;最后,依据回路之间的关联性的强弱选择每个回路的控制方式(精确控制或区域控制).仿真结果显示带有区域控制的分布式预测控制系统的调节时间比没有带区域控制的分布式控制系统明显缩短;同时,通过对回路控制方式的选择增加了精确控制的智能体数量.仿真结果证明了利用分布式区域预测控制方法可以提高系统的容错性,通过对系统的可控性和关联性进行分析,可以在精确控制和区域控制之间寻找到最优组合,从而达到快速精确的控制效果.     

基于遗传算法的航空弹药保障人员优化配置

航空弹药保障任务中人员合理高效的配置是一个多约束条件下的组合优化问题。在建立保障人员配置模型的基础上,通过操作因子对模型的合理描述,应用遗传算法对模型进行优化求解,得到合理的保障人员数量和最优的保障人员配置方案。实例仿真验证了模型的正确性及算法的有效性。     

数据融合技术在废弃弹药分类中的应用

为了对废弃弹药进行分类并安全处理,提出了基于数据融合技术的超声波检测弹体内部成份方法.应用超声检测仪采集大量弹体内部成份样本数据,运用数据融合技术建立神经网络融合模型,对超声波的首波、幅值、频率、增益等特征进行融和处理,从而判断弹药的种类.实验结果表明,该方法准确可靠,具有较高的推广应用价值.     

仿真软件在弹药设计中的应用

为提高弹药的设计效率,用ANSYS Workbench对发射的弹丸进行强度分析和结构分析,用LS-DYNA分析破片穿甲过程,用ANSYS的 AutoDyn分析聚能射流穿甲及爆炸分散过程,用ANSYS的Cart3D分析弹丸气动力,并对弹药设计方案数值仿真. 比较仿真结果与理论结果,优选出相对合理的设计方案. 结果表明应用仿真软件可有效缩短弹药设计周期,能为故障分析提供指导.     

Human‐Finger Electronics Based on Opposing Humidity‐Resistance Responses in Carbon Nanofilms

Carbon nanomaterials have excellent humidity sensing properties. Here, it is demonstrated that multiwalled carbon‐nanotube (MWCNT)‐ and reduced‐graphene‐oxide (rGO)‐based conductive films have opposite humidity/electrical resistance responses: MWCNTs increase their electrical resistance (positive response) and rGOs decrease their electrical resistance (negative response). The authors propose a new phenomenology that describes a “net”‐like model for MWCNT films and a “scale”‐like model for rGO films to explain these behaviors based on contributions from junction resistances (at interparticle junctions) and intrinsic resistances (of the particles). This phenomenology is accordingly validated via a series of experiments, which complement more classical models based on proton conductivity. To explore the practical applications of the converse humidity/resistance responses, a humidity‐insensitive MWCNT/rGO hybrid conductive films is developed, which has the potential to greatly improve the stability of carbon‐based electrical device to humidity. The authors further investigate the application of such films to human‐finger electronics by fabricating transparent flexible devices consisting of a polyethylene terephthalate substrate equipped with an MWCNT/rGO pattern for gesture recognition, and MWCNT/rGO/MWCNT or rGO/MWCNT/rGO patterns for 3D noncontact sensing, which will be complementary to existing 3D touch technology.     

提高工艺安全性的FOX-7合成方法?

为了提高合成工艺的安全性,提出了一锅法制备1,1-二氨基-2,2-二硝基乙烯(FOX-7)的方法。控制反应体系温度在15℃左右,采用蠕动泵将浓硫酸连续地加入到2-甲基-4,6-二羟基嘧啶与二氯甲烷的悬浮液中,固体原料溶解后,再将发烟硝酸滴加到反应物料中,进行硝化反应;然后连续滴加水到反应器中,进行水解开环反应;再经过固液分离、洗涤和干燥,得到FOX-7。探讨了硝化剂的加料方式对收率和工艺安全性的影响。结果表明:惰性溶剂的引入,分散了反应物,硝化反应释放的热量可以及时扩散,物料温度控制更平稳,消除了物料团聚现象,而且与硝硫混酸加料相比,采用浓硫酸与发烟硝酸分步加料的方式,升温速率可降低51.0%,FOX-7的收率由63.0%提高到了82.6%,工艺的安全性显著提升。