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71.
A design of ultrathin crystalline silicon solar cell with Si3 N4 circular truncated cone holes(CTCs) arrays on the top is proposed. In this article, we perform an optical simulation of the structure. The finite-difference time-domain method is used to calculate the optical absorption of different periods, radius of top and bottom circles and depth of Si3 N4 CTCs. The short-circuit current density generated by the optimized cells(30.17 mA/cm~2) is 32.44% more than the value gained by control group(with flat Si3 N4). Then adding a layer of back silver to allow us to better analyze optical absorption. Later, we simulate the optimization of the same configuration of different silicon thicknesses andfind that our structure does enhance the light absorption. This work uses a combined path towards achieving higher photocurrent ultrathin crystalline silicon solar cells by constructing the texture of anti-reflection coating.  相似文献   
72.
采用新颖的熔体旋甩(MS)结合放电等离子烧结(SPS)技术制备了单相Zn掺杂的Ⅰ-型Ba8Ga12Zn2Ge32笼合物,研究了熔体旋甩工艺对其微结构以及热电性能的影响. 结果表明,MS得到的薄带自由面主要由300nm—1μm的小立方体单晶组成,薄带经SPS烧结后得到了具有大量层状精细结构的致密块体. 与熔融+SPS工艺制备的试样相比,熔融+MS+SPS制备的Ba8Ga12Zn 关键词: 熔体旋甩 Ⅰ-型笼合物 热电性能  相似文献   
73.
In this paper, the travelling wave solutions for the generalized Burgers--Huxley equation with nonlinear terms of any order are studied. By using the first integral method, which is based on the divisor theorem, some exact explicit travelling solitary wave solutions for the above equation are obtained. As a result, some minor errors and some known results in the previousl literature are clarified and improved.  相似文献   
74.
Liu J  Shang LP  Qu WW  Deng H  Wu J 《光谱学与光谱分析》2010,30(10):2685-2688
提出了光谱数据解析中的信息冗余系数的问题,从光谱数据处理过程中波段优化选择的方法入手,考察了多环芳烃(polycyclic aromatic hydrocarbons,PAHs)中的蒽、芘和菲三组分混合体系的荧光光谱数据,采用化学计量学中的主成分回归分析和波段变量选择的窗口移动法,通过理论分析和实验论证得到结论:(1)荧光光谱信号中存在信息冗余;(2)经冗余优化后的荧光光谱数据可以反演出更真实的样本的定量信息,对光谱重叠严重的多组分混合体系,采用冗余优化分析过的数据可以增加预测模型的灵敏度和稳定性。  相似文献   
75.
In this work, a specific tumor‐targeted small molecular fluorophore for synchronous long‐duration cancer imaging, photodynamic therapy, and photothermal therapy is synthesized. This novel fluorophore exhibits specific targeting ability in certain tumors (U87MG, MDA‐MB‐231, A549, etc.) based on its inherent structure and efficiently generates local hyperthermia and reactive oxygen species simultaneously for imaging‐guided precise cancer therapy combining the photothermic and photodynamic effects under laser irradiation. Meanwhile, compared to traditional near infrared fluorophore, this novel fluorophore with significantly enhanced stability against photobleaching can prolong the time of tumor imaging and improve the phototherapy efficiency. This work presents a potential strategy to develop small‐molecule‐based cancer theranostic agents for simultaneous cancer targeting, imaging, and therapy.  相似文献   
76.
With the development of transportation, the tunnel has become one of the important facilities of railway, highway and subway transportation. However, fire hazards occurring inside the tunnel may incur huge numbers of casualties and property losses. In this paper, a breathing air supply zone combined with an upward ventilation assisted tunnel evacuation system (BTES) is introduced. It can be used to create a safe, smoke-free evacuation passageway out of the tunnel. The BTES is optimized to achieve high-performance. The impacts of heat release rates, fire source locations and fire detection times are also discussed.  相似文献   
77.
A facile approach to the synthesis of pressure and temperature dual‐responsive polystyrene (PS) microbeads with controlled sizes via dispersion polymerization is described. Three different luminophors are selected and directly introduced into the reaction system and thus incorporated into the resultant PS microbeads during polymerization. By manipulating the reaction conditions, including concentrations of the initiator and monomer, polarity of the reaction medium, and injection rate for the monomer, uniform PS microbeads with sizes ranging from 1 to 5 μm are obtained. When a light source centered at 365 nm is used to excite all the luminophors in the PS beads, three distinct and resolvable emission peaks corresponding well with the luminophors are observed. By taking advantage of their sensitive responses to both pressure and temperature, the PS beads can be utilized for quantitative measurements of these two stimulations simultaneously. The PS beads loaded with multiple luminophors have the ability to serve as building blocks for the fabrication of novel sensing and imaging devices and therefore provide a promising strategy for the study of aerodynamics.  相似文献   
78.
针对双开槽的双光栅开放式谐振腔,提出了一种基于矩形波导谐振腔理论的计算方法,给出TE04模式场分布的结构设计修正公式,用于进行准光学谐振腔结构设计优化,通过增强电子注区域的电场强度,可有效提高电子效率。同时对双光栅慢波结构"冷"色散特性进行了计算,分析了不同参数对其高频特性的影响。结果表明,双光栅槽宽和电子注通道宽度的变化会对其色散特性的频带上限产生较大影响。  相似文献   
79.
80.
王彦芳  冯琦  邓秀剑 《应用声学》2016,24(7):156-158
为降低目标识别算法复杂性且提高其抗噪能力,提出一种基于几何特征差异的目标识别算法。将获取到的目标图片经图像处理后提取轮廓,并以最小周长多边形算法构造目标轮廓的近似多边形;然后根据模板库标准目标做放大或缩小处理后使其面积与模板面积相等;再使用摆放算法使其与模板库图形部分重合;并提出一种改进型双向链表算法求多边形相交部分,通过计算相交部分面积大小达到识别图像的目的。经过仿真实验验证了此方法简单易行,能够快速识别目标。  相似文献   
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