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位移检测技术是几何量精密测量的基础,在当代精密制造领域应用广泛。光谱共焦位移测量技术具有对环境杂散光、被测物倾斜、材料类型不敏感,测量频率高以及分辨率高等优点,可以检测位移量、表面粗糙度、三维形貌以及单层或多层透明材料的厚度,在精密位移测量领域中占据重要地位。近年来,利用衍射光学元件提高光学系统性能的光谱共焦测量技术被广泛研究。文章综述了基于衍射色散原理的光谱共焦位移测量技术的研究进展。首先,介绍了光谱共焦位移测量原理和衍射光学元件的色散特性;其次,阐述了基于衍射色散原理的光谱共焦位移测量技术的发展历史及研究进展;最后展望了该技术的发展趋势。 相似文献
877.
Mn2+离子掺杂全无机钙钛矿(Mn2+∶CsPbX3,X=Cl, Br)纳米晶(NCs)具有宽发射带、长斯托克斯位移和高量子产率等优势,在固态照明、光电探测和成像等领域有广阔应用前景。然而,目前Mn2+掺杂的钙钛矿晶体量子产率很难超过70%,如何改善发光效率,同时调控Mn离子发射中心成为构建高质量白光LED的关键。文章通过CdCl2后处理技术,进行室温下阳离子交换,获得了高效发光的Cd2+和Mn2+共掺杂的CsPbCl3纳米晶。Mn的发射波长可以从604 nm连续调控到624 nm,实现稳定的红光发射。Cd离子掺杂改善了Mn-Cl八面体的晶体场环境,使Mn衰减寿命提高到1.32 ms。此外,通过绿色CsPbBr3纳米晶和蓝-橙双色Mn∶CsPb(ClBr)3纳米晶构建了高显色指数的暖白光发光二极管(WLED),其流明效率达60 lm/W,显色指数超过85。 相似文献
878.
Ting Wu Tianqun Lang Chao Zheng Wenlu Yan Yu Li Runqi Zhu Xin Huang Huae Xu Yaping Li Qi Yin 《Advanced functional materials》2023,33(7):2212109
The red blood cell membrane (RBCm) provides tight protection, lowers the immunogenicity, and prolongs the circulation time of drugs in vivo when acting as the coating of drug delivery systems. However, the cellular uptake and release of drugs are hindered by RBCm. Docetaxel (DTX) is the first-line medicine for treating triple-negative breast cancer (TNBC), but it induces tumor metastasis. To solve these dilemmas, in this study, the photosensitizer 1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbocyanine iodide (DiR)-modified RBCm (DM) is prepared, which is coated onto a hybrid micelle consisting of the prodrugs of DTX and the anti-metastasis agent calcitriol (CTL), obtaining a nanoparticle, named HDC-DM. In a 4T1 tumor-bearing mouse model, after injecting HDC-DM, the intratumoral DTX and CTL concentrations are increased by 1.7 and 2.5 times compared with the free drug groups. After irradiating tumors with near-infrared laser, DiR elicits the photothermal effect, triggering the rupture of RBCm and drug release, promoting drug penetration in tumors, and inducing immunogenic cell death. The tumor growth inhibition rate is 77%, and the formation of lung metastases is reduced by 82%, with good biocompatibility. It is suggested that the combination of phototherapy, chemotherapy, and anti-metastatic therapy using HDC-DM is expected to be a powerful strategy for treating TNBC. 相似文献
879.
Haohao Dong Liangzhu Zhang Yongping Liao Kai Huang Cheng Lian Xinghai Zhou Zhao Zhang Esko I. Kauppinen Zhong-Shuai Wu 《Advanced functional materials》2023,33(29):2301103
Micro-supercapacitors (MSCs) as high-power density energy storage units are designed to meet the booming development of flexible electronics, requiring simple and fast fabrication technology. Herein, a fast and direct solvent-free patterning method is reported to fabricate shape-tailorable and flexible MSCs by floating catalyst chemical vapor deposition (FCCVD). The nitrogen-doped single-walled carbon nanotubes (N-SWCNTs) are directly deposited on a patterned filter by FCCVD with designable patterns and facilely dry-transferred on versatile substrates. The obtained MSCs deliver an excellent areal capacitance of 3.6 mF cm−2 and volumetric capacitance of 98.6 F cm−3 at a scan rate of 5 mV s−1 along with excellent long-term cycle stability over 125 000 circles. Furthermore, the MSCs show good performance uniformity, which can be readily integrated via connection in parallel or series to deliver a stable high voltage (4 V with five serially connected devices) and large capacitance (5.1 mF with five parallel devices) at a scan rate of 100 mV s−1, enabling powering the light emitting displays. Therefore, this method blazes the trail of directly preparing flexible, shape-customizable, and high-performance MSCs. 相似文献
880.
Shiyu Huang Yuan Chang Zhuwei Li Jiaqi Cao Yurou Song Junfeng Gao Licheng Sun Jungang Hou 《Advanced functional materials》2023,33(21):2211631
Photoredox catalysis is a green solution for organics transformation and CO2 conversion into valuable fuels, meeting the challenges of sustainable energy and environmental concerns. However, the regulation of single-atomic active sites in organic framework not only influences the photoredox performance, but also limits the understanding of the relationship for photocatalytic selective organic conversion with CO2 valorization into one reaction system. As a prototype, different single-atomic metal (M) sites (M2+ = Fe2+, Co2+, Ni2+, Cu2+, and Zn2+) in hydrogen-bonded organic frameworks (M-HOF) backbone with bridging structure of metal-nitrogen are constructed by a typical “two-in-one” strategy for superior photocatalytic C N coupling reactions integrated with CO2 valorization. Remarkably, Zn-HOF achieves 100% conversion of benzylamine oxidative coupling reactions, 91% selectivity of N-benzylidenebenzylamine and CO2 conversion in one photoredox cycle. From X-ray absorption fine structure analysis and density functional theory calculations, the superior photocatalytic performance is attributed to synergic effect of atomically dispersed metal sites and HOF host, decreasing the reaction energy barriers, enhancing CO2 adsorption and forming benzylcarbamic acid intermediate to promote the redox recycle. This work not only affords the rational design strategy of single-atom active sites in functional HOF, but also facilitates the fundamental insights upon the mechanism of versatile photoredox coupling reaction systems. 相似文献