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101.
102.
用Excel可高效处理学生成绩,介绍了表格的设计、相关公式的使用和模板的制作.  相似文献   
103.
基于OpenGL进行导弹飞行过程仿真,研究了交互界面的设计技术、特殊效果产生技术、模型的数据驱动及视点变化技术和碰撞检测技术.  相似文献   
104.
Intravenous infusion of mice with viable allogeneic lymphocytes can produce donor-specific enhancement of skin graft survival, but only if the injected lymphocytes can persist in the host's recirculating lymphocyte pool for at least 3 days. We have investigated the relative roles of class I and class II MHC for C57BL/6 mice infused with lymphoid cells from co-isogenic strains mutated at class I MHC (bm1) or class II MHC (bm12), and for A.TH lymphoid cells infused into C3H (class I different, class II identical) or A.TH (class II different, class I identical). Injected cells differing from the host at class I MHC, but not at class II MHC, can be rapidly removed by host natural immune mechanisms (probably NK cells). Persistence is favored if the injected cells also carry host class I MHC, i.e., tolerance is more readily induced by injecting F1 (A x B) into A rather than B into A, consistent with the "missing self" hypothesis of NK recognition, with class I MHC being the relevant self-marker. Injected cells differing from the host at class II MHC but not at class I MHC always persist for at least 3 days, even when class I-different cells are being actively removed.  相似文献   
105.
Zhou X  Su XY 《Applied optics》1994,33(35):8210-8215
Systematic errors in phase-measuring profilometry that are introduced by the modulation transfer function of a digital image-acquisition device are analyzed. New phase expressions and phase-deviation formulas are given. The results for simulations and experiments demonstrate that the algorithm of phase-measuring profilometry cannot be regarded as a point-to-point operation. To obtain precise results, an optimum scheme for setting the measurement system is also proposed.  相似文献   
106.
Zhou Z  Drabik TJ 《Applied optics》1995,34(17):3048-3054
A coplanar refractive-diffractive doublet array employing surface-relief diffractive phase elements embedded within poly(methyl methacrylate) microlenses is introduced as an optomechanical building block for optoelectronic integrated systems. The design method, fabrication technology, and results are described. Coplanarity of the quadratic- and linear-phase elements constituting the doublet can reduce optomechanical complexity in applications to unguided optical interconnects.  相似文献   
107.
Under isothermal and linear heating conditions, the thermal stability of the three-dimensional metallic glass Ni68B21Si11, produced by rapid quenching of the denucleated melt (RQDM), has been systematically studied using PE DSC7 differential scanning calorimetry in relation to denucleation of liquid alloy prior to rapid quenching, pre-anneal treatment of amorphous specimens, and cooling rate. The following results were observed. First, the thermal stability of metallic glass prepared by RQDM is obviously enhanced because of the removal of pre-existing nuclei in advance. This is substantiated by the experimental data showing that the projected life of three-dimensional metallic glass Ni68B21Si11 is increased by an order of magnitude at 400 K. Secondly, pre-anneal treatment of the amorphous alloy leads to a reduction of temperature for the onset of crystallization,T x, and crystallization heat, H. Finally, quenching rates have little effect on the thermal stability of amorphous alloys.  相似文献   
108.
109.
Perovskite light-emitting diodes (PeLEDs) show promising prospects in the wide color gamut display owing to their ultra-narrow full width at half maximum (FWHM). However, up to now, all perovskite white LEDs integrated by standard red, green, and blue perovskite emitters, namely, monolithic white PeLEDs (WPeLEDs), have been rarely reported, owing to facing some issues, e.g., solvent incompatibility in solution technique, ion exchange, and energy transfer between different emission centers. Herein, centered on these issues, an optimal intermediate connection layer (ICL) of Po-T2T/LiF/Ag/HAT-CN/MoO3 is adopted to successfully develop monolithic tandem multicolor PeLEDs and WPeLEDs for the first time. The multicolor PeLEDs can achieve the best external quantum efficiency of 1.8% and the highest luminance of 4844 cd m−2. Besides, the red/green/blue (R/G/B) monolithic tandem WPeLED shows a standard white International Commission on Illumination coordinate of (0.33, 0.33) and achieves an extremely wide color gamut reaching  National Television Standards Committee of 130%. This study is the first to realize the standard R/G/B co-electroluminescence in a monolithic perovskite device and offers a feasible strategy for developing wide-color gamut perovskite displays.  相似文献   
110.
Despite the outstanding power conversion efficiency (PCE) of perovskite solar cells (PSCs) achieved over the years, unsatisfactory stability and lead toxicity remain obstacles that limit their competitiveness and large-scale practical deployment. In this study, in situ polymerizing internal encapsulation (IPIE) is developed as a holistic approach to overcome these challenges. The uniform polymer internal package layer constructed by thermally triggered cross-linkable monomers not only solidifies the ionic perovskite crystalline by strong electron-withdrawing/donating chemical sites, but also acts as a water penetration and ion migration barrier to prolong shelf life under harsh environments. The optimized MAPbI3 and FAPbI3 devices with IPIE treatment yield impressive efficiencies of 22.29% and 24.12%, respectively, accompanied by remarkably enhanced environmental and mechanical stabilities. In addition, toxic water-soluble lead leakage is minimized by the synergetic effect of the physical encapsulation wall and chemical chelation conferred by the IPIE. Hence, this strategy provides a feasible route for preparing efficient, stable, and eco-friendly PSCs.  相似文献   
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