摘要：A series of novel E-ring modified evodiamine derivatives were designed and synthesized as antitumor agents. Their capacity to interfere with the catalytic activity of topoisomerase Ⅰ and Ⅱ was evaluated by the relaxation assay. In vitro antitumor activity results revealed that compound 12 showed good antitumor activity with a broad spectrum. Its binding modes with topoisomerase Ⅰ and Ⅱ were clarified by molecular docking.

摘要：针对水下图像出现蓝绿色偏、雾化和噪声等问题,提出一种基于颜色线模型和多尺度融合的水下图像增强算法.首先,设计一种局部自适应颜色校正方法对退化图像进行预处理,提高图像颜色线拟合效果并降低图像色偏的程度;然后,构建一种利用颜色线和背景光矢量求解偏置来估计透射率的凸优化算法,求得准确的模型参数来恢复图像实现图像去雾;接着,将预处理后的图像利用白平衡算法来补偿颜色的深度选择性吸收所造成的偏色,将白平衡处理后的图像分别利用伽玛校正和基于颜色线约束的噪声抑制算法进行处理,分别得到提高全局对比度和抑制噪声的图像;最后,对去雾、对比度增强和低噪声图像进行多尺度融合,得到特征丰富的水下增强图像.实验结果表明:所提出方法能够有效解决水下图像的色偏、雾化和噪声现象;相对于各对比算法,在水下彩色图像质量评价指标和峰值信噪比上分别提高了18.37%和42.16%,更好地保留了水下图像的颜色并降低了图像噪声.

摘要：大电流加速器束管中,当带电粒子流通过束管时,会在束管中激励起高频场,为了降低对束流的影响,束管中产生的高次模需要利用阻尼器将高频场能量转换成热量并通过冷却装置导走。介绍了某混合型高次模阻尼器的研制及主要性能。阻尼器采用的吸收材料为铁氧体和碳化硅,吸收材料通过金属化和钎焊实现与金属基板的焊接。通过CST和COMSOL软件分别开展了微波性能仿真和热仿真,对阻尼器的结构进行了优化设计。阻尼器的测试结果表明:该混合型阻尼器的吸收效率与计算结果在1.7 GHz以下频段相接近,在1.7 GHz以上高频段后,仿真吸收效率高于实测结果,相差较大;真空漏率、极限真空、水路耐压均满足超导高频腔设计需求。

摘要：The main reason for the high strength in near-βtitanium alloys is the ultrafine precipitation of the acicular secondary a phase in theβ*** purpose of this study is to use the pseudo-spinodal mechanism to obtain the ultrafine a phase for the design of a new high-strength near-γtitanium *** calculations and TC21-(TC21+15 Mo)diffusion couple composition gradient experiments were used to demonstrate that TC21+3 Mo alloy can undergo a pseudo-spinodal decomposition to obtain the ultrafine a phase,resulting in a high-strength *** adjusting the heat treatment process to obtain a bimodal microstructure,the alloy exhibits a good balance between ultimate tensile strength(1351 MPa)and plasticity(8.5%strain).Thus,it was demonstrated that the pseudospinodal mechanism combined with a high-throughput diffusion couple technique is an effective method for designing high-strength titanium alloys.

摘要：SN0144i-XX井是一口目的层为马家沟组碳酸盐岩储层小井眼井,完钻井深3805 m,152.4 mm裸眼段长3040 m,最大井斜24°,最大狗腿度4.05°,钻井液密度1.16 g/cm^(3)。井口起仪器过程中Φ57 mm测井仪器串落井,因井眼、仪器尺寸较小,仪器串结构复杂,仪器串抗拉抗压参数受限,落井仪器状态不明等问题,采用常规打捞技术已不能满足Φ152.4 mm小井眼中Φ57 mm测井仪器串的打捞要求,为此,通过分析测井仪器结构,每趟打捞出井仪器结构及落鱼在井筒内的相对位置及状态,开展套捞一体式专用打捞工具的设计制作、打捞方案的制定等研究,采用磁定位仪器确定鱼头技术,精准确定鱼头位置,提高仪器打捞成功率,设计制作了Φ146 mm大引鞋+Φ110 mm卡瓦打捞筒、Φ143 mm套铣头栽钢丝+内嵌式Φ110 m卡瓦打捞筒、Φ143 mm套铣管开窗+内嵌式Φ110 mm卡瓦打捞筒等套捞一体式打捞工具,进行26次的连续打捞作业,耗时45 d成功捞出落井仪器串19 m。阐述了小井眼裸眼井测井仪器落井后开展的套捞一体式非常规打捞工具设计加工、打捞方案编制及关键打捞措施,为今后类似测井仪器落井非常规打捞作业提供了一定的技术参考。

摘要：研制了石英膜片的非本征法布里—珀罗(F-P)腔光纤传感器,用于强磁场和高电压环境的超声波检测,并对超声波信号进行测量。通过ANSYS对不同材料的膜片进行有限元仿真分析,得出各自的灵敏度、响应频率与膜片半径之间的关系,并选择性能适合的膜片材料研制了光纤传感器。通过设计解调系统,使用石英材料膜片的传感器测试超声波信号的频率,并对测得的信号与压电传感器测得信号进行对比分析。仿真结果表明:在相同半径和厚度的不同材料膜片下,石英玻璃材料的固有频率和灵敏度相对适中。实验测得压电传感器超声波频率为33 k Hz,F-P腔光纤传感器测得频率为31. 3 k Hz,2种传感器测得数据相近,实验表明:石英材料适合作为非本征F-P腔光纤传感器的膜片材料。

摘要：准确采集振动信号信息是轴承故障诊断的关键,利用传感器采集振动信号数据,经A/D转换后传输至STM32微控制器,STM32控制Wi-Fi模块将数据发送至PC,采用局部均值分解(LMD)方法对采集的振动数据进行分析处理,实现对滚动轴承运行状态的远程监控。实验结果表明:系统能够对滚动轴承振动信号进行精准采集和分析,传输性能好、速度快,适合在工业行业推广使用。

摘要：The diffusion-multiple method was used to determine the composition of Ti−6Al−4V−xMo−yZr alloy(0.45<x<12,0.5<y<14,wt.%),which can obtain an ultrafine α *** show that Ti−6Al−4V−5Mo−7Zr alloy can obtain an ultrafineαphase by using the α″phase assisted *** bimodal microstructure obtained with the heat-treatment process can confer the alloy with a good balance between the strength and *** deformation mechanism is the dislocation slip and the{1101}twinning in the primary α *** strengthening mechanism is α/β interface *** interface of(0001)α/(110)β has a platform−step structure,whereas(1120)α/(111)βinterface is flat with no steps.

摘要：The incidence of invasive fungal infections is increasing rapidly. Clinically available antifungal agents suffer from limited efficacy and severe resistance. There is an urgent need to discover antifungal lead compounds with novel chemical scaffold. On the basis of our previously identified tetrahydrocarbazole antifungal leads, the structure-activity relationship was further explored by modifying the scaffold and the side chains. Several targeted compounds showed potent activity against Candida species. Particularly, compound 13i showed better antifungal activity than the lead compound, which can be used as a good starting point for further optimization.

摘要：考虑复合材料定向管柔性变形对火箭弹运动的影响,用虚拟样机技术建立了复合材料定向管受载的力学模型,阐述了仿真计算的原理和算法。通过仿真建模和数值计算,得到了需要的数据结果,掌握了火箭弹在定向管内发射的运动规律和玻璃钢复合材料定向管的动态力学性能,为玻璃钢定向管的结构优化设计与制作提供参考和借鉴。