摘要：Objective To optimize the extraction procedure and obtain the maximum total polysaccharide yield from Turpiniae *** Response surface methodology(RSM),combining Plackett–Burman design(PBD),steepest ascent method,and Box–Behnken design(BBD),was *** significant factors contributing to polysaccharide production were determined by *** path of steepest ascent method was performed to rapidly reach the neighborhood of the optimum *** and RSM were applied to further investigate the mutual interaction between the variables and to define the optimal *** The significant factors contributing to polysaccharide production were enzyme concentration,extraction time,and liquid-to-solid *** optimal conditions for maximal TFP were:enzyme concentration of2.8%,extraction time of41min,and liquid-to-solid ratio of27mL/*** experimental yield of3.08%was in good agreement with the model-predicted yield of3.1%under the optimized *** This study was successfully applied to optimize the extraction conditions of Turpiniae Folium polysaccharide,which can contribute to its further production and application.

摘要：研究木质家具与原木试件内部缺损三维可视化,有助于木质文物精准干预性保护与木材高效规划利用。凸显三维成像技术可视化优势,对木质文物保护具有重要意义。本文采用philips16排CT——A机型Brilliace16对试件三维断层扫描。通过对CT扫描后原始图像的分割,获取品质较佳的三维数字模型。继而对分割后的图像进行切面与断面两个维度的手工着色,随后通过三维重建可得到开裂、虫洞、朽坏等不同形式缺损的三维形态,并可得到与之对应的精准三维模型。试验证明:通过三维重建,可获取木质试件内部不同类型三维缺损形态的可视化分析,可对缺损形态进行360°观察,并可获取三维缺损形态的表面积、体积等精准物理参数。本技术可为木质文物修复提供三维缺损形态的精准参数及直观可视化三维模型。

摘要：Forward modeling is the basis of inversion imaging and quantitative interpretation for DC resistivity ***,a numerical model of the DC resistivity method must be finely divided to obtain a highly accurate solution under complex conditions,resulting in a long calculation time and large ***,we propose a 3D numerical simulation method in a mixed space-wavenumber domain to overcome this *** partial differential equation about abnormal potential is transformed into many independent ordinary differential equations with different wavenumbers using a 2D Fourier transform along the x axis and y axis *** this way,a large-scale 3D numerical simulation problem is decomposed into several 1D numerical simulation problems,which significantly reduces the computational and storage *** addition,these ordinary 1D differential equations with different wavenumbers are independent of each other and high parallelelism of the *** are solved using a finite-element algorithm combined with a chasing method,and the obtained solution is modified using a contraction *** this method,the vertical direction is reserved as the spatial domain,then grid size can be determined flexibly based on the underground current density distribution,which considers the solution accuracy and calculation *** addition,for the first time,we use the contraction operator in the integral equation method to iterate the *** algorithm takes advantage of the high efficiency of the standard Fourier transform and chasing method,as well as the fast convergence of the contraction *** verified the accuracy of the algorithm and the convergence of the contraction *** with a volume integral method and goal-oriented adaptive finite-element method,the proposed algorithm has lower memory requirements and high computational efficiency,making it suitable for calculating a model with large-scale ***,differ

摘要：On the eve of the occurrence of geological hazards,part of the rock and soil body begins to burst,rub,and fracture,generating infrasound signals propagating outward.3D advanced positioning of the landslide has remained unsolved,which is important for disaster *** the Fourier transform and Hankel transform of the wave equation in cylindrical coordinates,this work established a three-dimensional axisymmetric sound field model based on normal waves,and designed a 4-element helix triangular pyramid array with vertical and horizontal sampling *** on this,the three-dimensional matching localization algorithm of infrasound for geological hazards is *** the algorithm to the infrasound signal localization of rock and soil layers,it was found that the helix triangular pyramid array can achieve accurate estimation of depth and distance with a smaller number of array elements than the traditional array,and may overcome the azimuth symmetry *** study shows the application prospects of this method for predicting geohazards position several hours in advance.

摘要：与其他增材制造技术相比,光固化3D打印成形技术制备结构复杂、致密度高、表面精度高的陶瓷具有独特的优势,并逐步成为陶瓷增材制造领域的研究热点。然而,氮化硅陶瓷的高折射率和高吸光度等特征导致光固化成形困难,限制了其发展和应用。本文分别从光固化氮化硅陶瓷的浆料流变性能以及固化性能进行分析,总结归纳出氮化硅浆料在流变性能和固化性能方面面临的问题,进一步汇总了提升氮化硅陶瓷浆料光固化性能的研究工作,并对粉体改性、调控树脂组成等几种方法进行分析与探讨。最后,对氮化硅陶瓷光固化3D打印的未来发展趋势和方向进行了详细阐述。

摘要：为解决自动焊接机器人系统在采煤机滚筒焊接过程中出现的滚筒姿态不确定的问题,设计一种调心定位装置对滚筒进行准确定位,此装置的研发是焊接机器人系统中的一项关键技术。其中,液压系统是装置稳定运行的关键,为了验证定位装置液压系统设计的可行性,利用Amesim仿真软件对其进行建模仿真,通过仿真分析,该液压系统的设计符合要求,具有一定的合理性与实用性。

摘要：针对高频环境下寄生参数引起氮化镓(GaN)金属氧化物半导体场效应晶体管(MOSFET)开关损耗大的问题,提出一种基于GaN开关器件的半桥电路集成方案。该方案的实现基于寄生参数较低的高功率密度GaN半桥模块(GS66516T),通过有限元分析提取寄生参数联合电气模型参数仿真分析,从而实现驱动电路和功率环路的优化设计。最后,研制一台4kW两相交错并联降压变换器原理样机,并搭建双脉冲测试(DPT)平台用于分析测试实验中寄生参数对开关过程的影响。实验结果表明,该样机可实现功率密度536.19 W/in^(3),峰值效率97.65%,并具有较好的动态开关特性。

摘要：为了有效提升车载轨道缺陷智能巡检结果的准确性,提出一种基于计算机视觉的车载轨道缺陷智能巡检系统。在高速运动状态下,采用高分辨率摄像机实时采集和存储车载轨道图像,通过车载轨道图像采集模块、车载轨道缺陷检测和信息管理模块组成系统硬件部分。滤除车载轨道图像中的噪声,提取车载轨道缺陷特征,通过计算机视觉技术建立计算机视觉模型,将特征输入到模型中,最终完成车载轨道缺陷智能巡检。实验结果表明,所提系统可以有效巡检车载轨道缺陷,同时还可以满足实时性检测需求,可为未来铁路的发展提供可靠的价值参考。

摘要：封严片在航空发动机的密封和减振中起到关键作用。针对某型航空发动机多次发生因封严片硬度低导致的开裂和变形问题,提出了将封严片材料由固溶态GH600材料更换为冷轧态GH5188材料的优化改进方案。试验结果表明,冷轧态GH5188材料封严片在设计许用上限温度条件下保温100h后,硬度依然可保持在350HV以上的较高水平,且即使经历一定的短时超温后,硬度仍能与改进前封严片的硬度相当。提出的优化改进方案效果明显,可以保证封严片长期工作可靠性,具有良好的工程实用价值。

摘要：受温度及密度等环境效应影响,温稠密物质的电子结构发生显著变化,其理论描述非常复杂,精密实验测量亦极其困难.本文发展了基于X射线荧光光谱研究温稠密物质离化分布的实验方法,结合理论研究有助于深入理解温稠密物质的电子结构变化.在万焦耳激光装置上,设计特殊构型黑腔复合加载产生数十eV、近固体密度的稠密Ti物质,利用激光辐照V产生的热发射线泵浦Ti的荧光,并采用晶体谱仪诊断样品的X射线荧光光谱.实验中获得冷样品和加载样品的荧光光谱,观测到加载样品K_(α)及K_(β)荧光谱线相对于冷样品光谱在高能侧的显著变化,结合理论计算解释了加载样品荧光谱线的变化主要来源于其温度上升后离化分布的改变,建立了基于X射线荧光光谱的温稠密物质离化分布实验研究能力.