碳纳米管作为新型催化材料的发展

纳米材料真正作为研究领域的历史至今还不到一个世纪,在这不到一世纪时间里,纳米材料在人们越来越炽热的关注中飞速发展。作为纳米材料,其粒子由于尺寸的微观性,以及量子力学的出现,便具有了一些特殊的性质,包括量子尺寸效应、小尺寸效应、表面效应以及宏观量子隧道效应。在石油化工领域,催化剂是整个行业的命脉之一,而纳米材料由于其特殊的性质,使其在催化材料方面也开始逐渐崭露头角,并被专业人士视为富有前景的新型催化材料。本文中将以碳纳米管(CNTs)为例着重介绍其作为催化材料的发展进程并进行展望。     

Low-threshold lasing in a plasmonic laser using nanoplate InGaN/GaN

Plasmonic nanolaser as a new type of ultra-small laser,has gain wide interests due to its breaking diffraction limit of light and fast carrier dynamics characters.Normally,the main problem that need to be solved for plasmonic nanolaser is high loss induced by optical and ohmic losses,which leads to the low quality factor.In this work,InGaN/GaN nanoplate plasmonic nanolaser with large interface area were designed and fabricated,where the overlap between SPs and excitons can be en-hanced.The lasing threshold is calculated to be ～6.36 kW/cm2,where the full width at half maximum (FWHM) drops from 27 to 4 nm.And the fast decay time at 502 nm (sharp peak of stimulated lasing) is estimated to be 0.42 ns.Enhanced lasing charac-ters are mainly attributed to the strong confinement of electromagnetic wave in the low refractive index material,which im-prove the near field coupling between SPs and excitons.Such plasmonic laser should be useful in data storage applications,bio-logical application,light communication,especially for optoelectronic devices integrated into a system on a chip.     

Comprehensive analysis on anomalous phenomenon of ethanol-soluble poly(vinyl butyral) membrane for ethanol recovery via pervaporation

Poly(vinyl butyral) (PVB) is selected as a promising ethanol-permselective membrane based on the solubility parameter theory; however, it exhibits anomalous water perm-selectivity in practical pervaporation (PV) process. Comprehensive analysis based on experimental and theoretical methods were carried out to explore the inherent mechanism of the anomalous performance. Firstly, sum frequency generation vibrational spectra and contact angle were developed to quantify the surface reconstruction of membrane in air and ethanol, which indicated that hydrophilic hydroxyl tended to expose on membrane surface with ethanol thus improving the membrane affinity to water. Meanwhile, swelling behaviors proved more water would accumulate in the ethanol swollen membrane. Furthermore, theoretical analysis in terms of sorption and diffusion process, based on the UNIFAC-FV model and Fujita free-volume theory, confirmed the mechanism of anomalous phenomenon of PVB membrane. The comprehensive investigation was expected to provide insights into the basic separation mechanism of PV process.     

采用柔性集成与逻辑分支技术电缆的研制

随着武器装备的发展,电气连接与信号传输越来越复杂,对电缆网布线的空间大小、可靠性、电磁兼容、可辨性等提出了更高的要求。采用柔性集成与逻辑分支技术设计布线,可以节省布线空间,具有柔性好、重量轻、高可靠性、电磁兼容等特点,同时避免穿舱、辨色等一系列问题。这种布线技术对减轻武器装备重量、提高综合性能具有很高的实用价值。     

基于深度学习的路面不平度等级识别研究

准确的路面激励信息对汽车行驶安全性和乘坐舒适性有重要影响.针对目前路面不平度等级识别算法存在复杂和准确率低等问题,提出了一种注意力门控循环单元(BiGRU-Attention)网络和车辆振动响应的路面不平度等级识别算法.首先,通过滤波白噪声法建立随机输入路面模型,1/4车辆振动模型平顺性仿真实验获取车辆振动响应信号,选择滑动窗口为1 s截取样本构造数据集;然后,通过BiGRU网络学习样本信号的深层次信息,Attention机制优化时刻特征对辨识结果的贡献率比重,快速准确地识别出路面不平度等级;最后通过消融实验实现算法的验证.实验结果表明,基于BiGRU-Attention路面不平度等级识别算法的准确率可达96.9％,相比基础模型有1％～3％的提升.该算法能够准确识别路面不平度等级,为车辆动力学控制提供有力的理论依据.     

主轴集成式光纤光栅切削力测量方法研究

为了稳定可靠地测量切削加工过程中切削力的大小以对机床的加工状态进行监测(TCM),对基于光纤光栅(FBG)传感技术的主轴集成式切削力测量方法进行了研究。基于光纤光栅应变检测原理和Γ形梁的受力分析,提出了4个完全相同并且对称的Γ形梁弹性体结构;通过对切削力传递规律的分析,建立起了主轴集成式切削力测量理论模型并确定FBG的布点;为了验证模型的准确性,搭建了主轴集成式光纤光栅切削力测量实验平台,最后通过实验验证了该方法的可行性和可靠性。     

对羟基偶氮苯甲酸的合成及光致变色性能研究

研究对羟基偶氮苯甲酸(PHABA)的合成方法及其光响应性能。在低温盐酸条件下,完成对氨基苯甲酸与亚硝酸钠的重氮化反应,再与苯酚pH=9条件下完成偶合反应,产品收率82.6%。氯仿溶剂中,PHABA特征吸收波长为357 nm和240 nm,紫外光照射实验显示,PHABA具备动力学一级反应特征的顺反异构光致变色特性,速率常数为7.46×10-4 min-1。     

现浇正交异性钢筋混凝土空心板施工技术

以石棉水泥砂浆离心管作为内模衬管,浇筑混凝土后构成现浇混凝土空心板。该结构设宽扁梁或暗梁,可降低结构高度,增大使用空间,具有刚度大、自重轻、抗震好、用料省等优点,具有良好的经济效益与社会效益。     

量热仪测定热值在建材检测中的问题探讨

国家对建筑防火的要求日益严格,而利用量热仪测定热值是一种重要的检测手段。本文以相关检测标准为核心,阐述量热仪的测定原理及试验方法,对检验检测中的相关内容进行分析,提供量热仪期间核查和不确定度评定的大体思路,及提出完善质量管理体系的建议,以保证热值测定和检验检测过程的准确性和可信性。