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91.
A sort of tubular ultrasonic radiator used in ultrasonic liquid processing is studied. The frequency equation of the tubular radiator is derived, and its radiated sound field in cylindrical reactor is calculated using finite element method and recorded by means of aluminum foil erosion. The results indicate that sound field of tubular ultrasonic radiator in cylindrical reactor appears standing waves along both its radial direction and axial direction, and amplitudes of standing waves decrease gradually along its radial direction, and the numbers of standing waves along its axial direction are equal to the axial wave numbers of tubular radiator. The experimental results are in good agreement with calculated results. 相似文献
92.
Synthesis,cytotoxicity and anti‐metastatic properties of new pyridyl–thiazole arene ruthenium(II) complexes 下载免费PDF全文
A series of novel ruthenium(II)–cymene complexes ( 1 – 8 ) containing substituted pyridyl–thiazole ligands, [Ru(η6‐p‐cymene)(L)Cl]Cl (L = N,N‐chelating derivatives), have been synthesized and characterized using elemental analysis, infrared, 1H NMR and 13C NMR spectroscopies and mass spectrometry. All these complexes not only display marked cytotoxicity in vitro against three different human cancer cell lines (HeLa, A549 and MDA‐MB‐231), but also exhibit promising anti‐metastatic activity at sub‐cytotoxic concentrations. Cell cycle analysis shows that the ruthenium(II) complex‐induced growth inhibition was mainly caused by S‐phase cell cycle arrest. Further protein level analysis suggests that compound 5 may exert antitumor activity via a p53‐independent mechanism. 相似文献
93.
Yihui Yuan Biye Niu Qiuhan Yu Xin Guo Zhanhu Guo Jun Wen Tao Liu Haiquan Zhang Ning Wang 《Angewandte Chemie (International ed. in English)》2020,59(3):1220-1227
Based on the photoinduced photothermal, photoelectric, and photocatalytic effects of black phosphorus (BP) nanosheets, a BP‐PAO fiber with enhanced uranium extraction capacity and high antibiofouling activity is fabricated by compositing BP nanosheets into polyacrylamidoxime (PAO). The photothermal effect increases the coordination interaction between UO22+ and the functional amidoxime group, and the photoelectric effect produces the surface positive electric field that exhibits electrostatic attraction to the negative [UO2(CO3)3]4?, which all increase the capacity for uranium adsorption. The photocatalytic effect endows the adsorbent with high antibiofouling activity by producing biotoxic reactive oxygen species. Owing to these three photoinduced effects, the photoinduced BP‐PAO fiber shows a high uranium adsorption capacity of 11.76 mg g?1, which is 1.50 times of the PAO fiber, in bacteria‐containing natural seawater. 相似文献
94.
Qiuhan Yu Yihui Yuan Lijuan Feng Tiantian Feng Wenyan Sun Ning Wang 《Angewandte Chemie (International ed. in English)》2020,59(37):15997-16001
The unique three‐dimensional structure of spidrion determines the outstanding mechanical properties of the spider silk fiber. Inspired by the similarity of the three‐dimensional structure of superb‐uranyl binding protein (SUP) to that of spidroin, a dual‐SUP (DSUP) chimeric protein fiber with high tensile strength is designed. The DSUP hydrogel fiber exhibits a loofah‐shape structure by the cross‐interaction of the protein nanofiber. Full exposure of abundant functional uranyl‐binding sites in the stretchable loofah‐shape hydrogel protein fiber give the DSUP fiber a groundbreaking uranium extraction capacity of 17.45 mg g?1 with an ultrashort saturation time of 3 days in natural seawater. This work reports the design of an adsorbent with ultrahigh uranium extraction capacity and explores a strategy for fabricating artificial high‐strength functional non‐spidroin protein fiber. 相似文献
95.
Fanghong Qin Ting Wan Jiangyuan Qiu Yihui Wang Biyuan Xiao Zaiyin Huang 《物理化学学报》2020,36(6):1905087-0
利用光微热量-荧光光谱联用技术,对光催化过程的热谱和光谱信息同步监测,获取了五个温度下,g-C_3N_4@Ag@Ag_3PO_4光催化降解罗丹明B的原位热动力学、光谱动力学信息,探究了温度对相关参数的影响。结果表明,催化降解反应分为三个阶段:(i)污染物和催化剂的光响应过程;(ii)光响应吸热和污染物降解放热的竞争过程;(iii)保持稳定的放热率。吸热和放热的竞争过程符合一级动力学,降解速率随着温度的升高而增大;稳定放热阶段为拟零级反应,在283.15 K、288.15 K、293.15 K、298.15 K、303.15 K下的放热速率分别为0.4668±0.3875μJ·s~(-1)、0.5314±0.3379μJ·s~(-1)、0.5064±0.3234μJ·s~(-1)、0.5328±0.3377μJ·s~(-1)、0.5762±0.3452μJ·s~(-1)。本研究为探究光催化过程的原位热力学、热动力学及光谱信息及机理的推测提供科学依据。 相似文献
96.
Yongbo Deng Zhenyu Liu Ping Zhang Yongshun Liu Yihui Wu 《Journal of computational physics》2011,230(17):6688-6708
This paper discusses the topology optimization of unsteady incompressible Navier–Stokes flows. An optimization problem is formulated by adding the artificial Darcy frictional force into the incompressible Navier–Stokes equations. The optimization procedure is implemented using the continuous adjoint method and the finite element method. The effects of dynamic inflow, Reynolds number and target flux on specified boundaries for the optimal topology of unsteady Navier–Stokes flows are presented. Numerical examples demonstrate the feasibility and necessity of this topology optimization method for unsteady Navier–Stokes flows. 相似文献
97.
An evaluation for objectively assessing the target detectability in night vision color fusion images is proposed.On the assumption that target detectability could be modeled as the perceptual color variation between the target and its optimal sensitive background region,we propose an objective target detectability metric in CIELAB color space defined by four color information features:target luminance,region perceptual luminance variation in human vision system,region hue difference,and region chroma difference.Experimental results show that this proposed metric is perceptually meaningful because it corresponds well with subjective evaluation. 相似文献
98.
电偶腐蚀会导致受载结构中内力的变化,从而改变结构性能。研究电偶腐蚀对结构内力的影响规律,利于提高相关结构的设计水平。设计接触端面为圆平面的圆柱形电极,采用恒位移加载方式使两个接触面相互压紧,同时将电极浸泡在质量分数3.5%的 NaCl溶液中进行腐蚀,测试给出了压紧力随腐蚀时间的变化曲线。与实验状态相对应,用电极表层腐蚀区的径向和轴向尺寸以及等效弹性常数表征电偶腐蚀效应,根据实验观察近似取定腐蚀区尺寸,建立微观尺度的材料性能模拟模型和宏观尺度的结构力学模拟模型,计算给出了腐蚀区的材料性能参数和腐蚀一定时间后电极之间的压紧力,计算结果与实验结果大致吻合。该项研究同时为数值模拟电偶腐蚀对结构力学行为的影响提供了新的方法。The structural internal forces as well as properties may be changed by galvanic corrosion. Studying and understanding the laws of galvanic corrosion effects on structural internal forces is useful for promotion of design level. The experiments and measurements of macro compressed loading and corrosion for a pair of galvanic electrodes subjected to fixed displacement loading are performed and the curve of the compressive force between the galvanic electrodes versus corrosion time is obtained. According to the corroded surface morphologies obtained by scanning electron microscope (SEM) after rust cleaning, the meso-scale finite element model for the corroded zone is developed by using the homogenization method in terms of representative volume element (RVE) and the equivalent elasticity constants of the corroded zone are computed. Meanwhile, the sizes of the corroded zone are determined approximately by the corroded surface morphologies and a macro-scale finite element model for the whole sample is developed and the compressive force is calculated which basically agrees well with the experimental value. Therefore, a new method to numerically simulate the influences of galvanic corrosion on structural mechanical behavior is developed. 相似文献
99.
100.
聚二甲基硅氧烷表面亲水性的研究 总被引:4,自引:0,他引:4
为了使聚二甲基硅氧烷(PDMS)具有较稳定的亲水性表面,利用氧等离子体技术对PDMS表面进行处理。研究了氧等离子体处理PDMS表面的时间、功率、氧气流量等参数对表面亲水性的影响,通过接触角测量和X-射线光电子能谱(XPS)对处理效果进行了评价。实验表明:PDMS经氧等离子体处理后放置700 h的表面接触角为72°,达到了持久改性的目的;XPS分析表明,表面亲水性的改善主要是由于表面极性成分的增加,最后讨论了氧等离子体处理PDMS表面的改性机理。 相似文献