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Lou Ching-Wen Wu Zong-Han Lee Mong-Chuan Lin Jia-Horng 《Research on Chemical Intermediates》2018,44(8):4957-4970
Research on Chemical Intermediates - A highly efficient oligomer antimicrobial agent, polyhexamethylene guanidine hydrochloride (PHMGH), is added to mixtures of polyvinylpyrrolidone (PVP)/chitosan... 相似文献
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Ching-Cheng Chuang Jui-che Tsai Chung-Ming Chen Zong-Han Yu Chia-Wei Sun 《Optics Communications》2012,285(8):2236-2241
Diffuse optical tomography (DOT) is an emerging technique for functional biological imaging. The imaging quality of DOT depends on the imaging reconstruction algorithm. The SIRT has been widely used for DOT image reconstruction but there is no criterion to truncate based on any kind of residual parameter. The iteration loops will always be decided by experimental rule. This work presents the CR calculation that can be great help for SIRT optimization. In this paper, four inhomogeneities with various shapes of absorption distributions are simulated as imaging targets. The images are reconstructed and analyzed based on the simultaneous iterative reconstruction technique (SIRT) method. For optimization between time consumption and imaging accuracy in reconstruction process, the numbers of iteration loop needed to be optimized with a criterion in algorithm, that is, the root mean square error (RMSE) should be minimized in limited iterations. For clinical applications of DOT, the RMSE cannot be obtained because the measured targets are unknown. Thus, the correlations between the RMSE and the convergence rate (CR) in SIRT algorithm are analyzed in this paper. From the simulation results, the parameter CR reveals the related RMSE value of reconstructed images. The CR calculation offers an optimized criterion of iteration process in SIRT algorithm for DOT imaging. Based on the result, the SIRT can be modified with CR calculation for self-optimization. CR reveals an indicator of SIRT image reconstruction in clinical DOT measurement. Based on the comparison result between RMSE and CR, a threshold value of CR (CRT) can offer an optimized number of iteration steps for DOT image reconstruction. This paper shows the feasibility study by utilizing CR criterion for SIRT in simulation and the clinical application of DOT measurement relies on further investigation. 相似文献
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胶原接枝改性用于制备红外低发射率涂层的研究 总被引:6,自引:0,他引:6
用甲基丙烯酸甲酯在硝酸铈铵和偶氮二异丁腈的联合引发下对胶原进行接枝共聚改性,并用制得的胶原接枝共聚物颗粒与氧化铟纳米粒子复合制成涂层.研究了接枝反应温度及萃取剂对胶原接枝共聚物及其复合物涂层的红外发射率的影响,同时对复合物涂层红外发射率的降低机理进行了初步探讨.结果表明,在反应温度为50~55℃时,先后用丙酮和水作为萃取剂,可制得粒径为40~80nm的胶原接枝共聚物颗粒,该颗粒与氧化铟纳米粒子复合后,涂层的红外发射率(8~14μm)较单一的胶原接枝共聚物和氧化铟纳米粒子的红外发射率明显降低,胶原接枝共聚物纳米颗粒和氧化铟纳米粒子之间显示出较强的复合协同效应. 相似文献
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周口店北京猿人化石产地,附近有四个岩溶洞穴(即笫1地点猿人洞、第15地点洞穴、笫4地点新洞和山顶洞),为古人类居住过.这些洞穴的发育深受地质构造控制,按其形态主要分垂直型和水平型两类.其中猿人洞规模最大,是复杂的垂直型溶洞系统,堆填了40余米厚的洞穴地层.根据岩溶洞穴发育的理论,洞内堆积物与洞外堆积物的对比分析,以及绝对年龄测定资料,并参考了过去的发掘记录,可以将猿人洞穴的演化过程大致分为5个阶段,每个阶段均与古人类的生活活动有密切的关系. 相似文献
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Yang JT Yang ZH Chen CY Yao DJ 《Langmuir : the ACS journal of surfaces and colloids》2008,24(17):9889-9897
To clarify a driving mechanism for the self-movement of a droplet across hydrophobic textured surfaces in series and to develop applications for a microfluidic device, we report a theoretical model, a microfabrication technique, and experimental measurements. The contact angle of a droplet on a composite surface, the stable surface energy level, and the energy barrier caused by hysteresis were investigated. With increasing patterned density of the microstructure, the contact angle and stable surface energy decreased gradually, but the energy barrier increased. Both the analytical results and the experimental measurements show that the surface energy for a suspended status is greater than that for a collapsed status, which produces increased energy to generate the movement of a droplet. An analysis of interactions between actuation force, resistive force, and viscous force during the motion of a droplet is based on the equilibrium between forces. From the perspective of energy conversion, the difference in surface energy between a higher state and a lower state would drive a single droplet and make it move spontaneously if it could overcome the static friction force resulting from hysteresis and the kinetic friction force under droplet movement. The mean velocity in the present device, measured to be 62.5 mm s (-1), agrees satisfactorily with the theoretical prediction. The model developed for the energy levels enables us to assess the contact mode of a droplet placed on the patterned surface. For a prediction of the transport capability of the designed devices, a theoretical interpretation of the conversion between the surface energy and the kinetic energy of the droplet establishes a criterion that the pattern density of a textured surface should be less than 0.76. The effective rate of energy conversion is estimated to be 20.6%. 相似文献
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