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151.
Clinical information about a variety of disorders is available through blood cell counting, which is usually done by manual methods. However, manual methods are complex, time-consuming and susceptible to the subjective experience of inspectors. Although many efforts have been made to develop automated blood cell counting algorithms, the complexity of blood cell distribution and the highly overlapping nature of some red blood cells (RBCs) remain significant challenges that limit the improvement of analytical accuracy. Here, we proposed an end-to-end method for blood cell counting based on deep learning. Firstly, U-Net++ was used to segment the whole blood cell image into several regions of interest (ROI), and each ROI contains only one single cell or multiple overlapping cells. Subsequently, YOLOv5 was used to detect blood cells in each ROI. Specifically, we proposed several strategies, including fine classification of RBCs, adaptive adjustment for non-maximal suppression (NMS) threshold and blood cell morphology constraints to improve the accuracy of detection. Finally, the detection outcomes for each ROI were combined and superimposed. The results show that our method can effectively address the issue of high overlap and precisely segment and detect blood cells, with a 98.18% accuracy rate for blood cell counting. 相似文献
152.
Chunliu Xu Weibo Hua Qinghua Zhang Yuan Liu Rongbin Dang Ruijuan Xiao Jin Wang Zhao Chen Feixiang Ding Xiaodong Guo Chao Yang Liangrong Yang Junmei Zhao Yong-Sheng Hu 《Advanced functional materials》2023,33(33):2302810
Na superionic conductor of Na3MnTi(PO4)3 only containing high earth-abundance elements is regarded as one of the most promising cathodes for the applicable Na-ion batteries due to its desirable cycling stability and high safety. However, the voltage hysteresis caused by Mn2+ ions resided in Na+ vacancies has led to significant capacity loss associated with Mn reaction centers between 2.5–4.2 V. Herein, the sodium excess strategy based on charge compensation is applied to suppress the undesirable voltage hysteresis, thereby achieving sufficient utilization of the Mn2+/Mn3+ and Mn3+/Mn4+ redox couples. These findings indicate that the sodium excess Na3.5MnTi0.5Ti0.5(PO4)3 cathode with Ti4+ reduction has a lowest Mn2+ occupation on the Na+ vacancies in its initial composition, which can improve the kinetics properties, finally contributing to a suppressed voltage hysteresis. Based on these findings, it is further applied the sodium excess route on a Mn-richer phosphate cathode, which enables the suppressed voltage hysteresis and more reversible capacity. Consequently, this developed Na3.6Mn1.15Ti0.85(PO4)3 cathode achieved a high energy density over 380 Wh kg−1 (based on active substance mass of cathode) in full-cell configurations, which is not only superior to most of the phosphate cathodes, but also delivers more application potential than the typical oxides cathodes for Na-ion batteries. 相似文献
153.
Lisi Yang Shuaishuai Shen Xiang Chen Huan Wei Dongdong Xia Chaowei Zhao Ningfang Zhang Yuanyuan Hu Weiwei Li Hao Xin Jinsheng Song 《Advanced functional materials》2023,33(36):2303603
The electron transport layer (ETL) is a critical component in achieving high device performance and stability in organic solar cells. Conjugated polyelectrolytes (CPEs) have become an attractive alternative due to film-forming properties and ease of preparation. However, p-type CPEs generally exhibit poor charge mobility and conductivity, incorporation of electron-withdrawing units forming alternated D-A conjugated backbone can make up for these deficiencies. Herein, the ratio of electron withdrawing moieties are further increased and two poly(A1-alt-A2) typed PIIDNDI-Br and PDPPNDI-Br based on the combination of naphthalene diimide (NDI) with isoindigo (IID) or diketopyrrolopyrrole (DPP) via direct arylation polycondensation are synthesized. These CPEs possess excellent alcohol solubility, a suitable lowest unocuppied molecular orbital energy level, and work function tunability. Surprisingly, the incorporation of IID and DPP units generate distinct self-doping behaviors, which are confirmed by UV–vis absorption and ESR spectra. However, no matter doped or undoped, both CPEs present better charge-transporting properties and conductivity when utilized as ETLs. The PIIDNDI-Br and PDPPNDI-Br display good universal compatibility with the blend of PM6:Y6 and PM6:L8-BO, and PCEs of 18.32% and 18.36% are obtained, respectively, which also present excellent storage stability. In short, the combination of two different acceptors demonstrates an efficient strategy to design highly efficient ETLs for high performance photovoltaic devices. 相似文献
154.
Organic-inorganic hybrid perovskite solar cells (PSCs) with unique properties exhibit their powerful competitiveness in the photovoltaic field over the past few years. However, the challenges of stability for perovskite devices limit the commercialization and further development. The 2D/3D hybrid structures combine the superior efficiency of bulk perovskites and the superior stability of layered perovskites and gradually get hotspots of the photovoltaic field. In addition, there remains a lack of comprehensive understanding and systematic summary of the function of 2D perovskite attributed to the complex nature of 2D/3D structures. Here, the latest progress of 2D/3D hybrid structures and focus on the functionality of 2D phases in mixed structures and the underlying mechanism from the perspective of their different distributions in the perovskite layer is summarized. Then, the insight and vital factors for overall improvements in the stability of 2D/3D structures are thoroughly discussed. Finally, it is expected that this review will contribute to the present challenges and future research prospects in the photovoltaic industry. 相似文献
155.
为提高雷达旋翼无人机的识别效果,本文提出一种基于多域特征融合的旋翼无人机分类方法。首先利用K波段连续波(Continuous Wave,CW)雷达观测多旋翼无人机,对采集到的雷达回波信号进行信号处理依次得到时频图、节奏速度图(Cadence?Velocity Diagram, CVD)和节奏频谱图(Cadence Frequency Spectrum,CFS),然后将时频图和CVD图分别输入SqueezeNet网络,CFS数据输入一维卷积神经网络(1?D?CNN)提取回波信号在时频域、节奏速度域和节奏频率域的特征,最后将特征融合输入支持向量机(Support Vector Machine, SVM)进行分类。实测雷达数据处理的结果表明基于多域特征融合的旋翼无人机分类识别方法对三类旋翼无人机的分类准确率达到99.14%。 相似文献
156.
157.
Hybrid Catalyst Coupling Zn Single Atoms and CuNx Clusters for Synergetic Catalytic Reduction of CO2
Xiaosong Hu Xinyu Liu Xin Hu Chaoyue Zhao Qingxin Guan Wei Li 《Advanced functional materials》2023,33(16):2214215
Reverse water-gas shift (RWGS) reaction is the initial and necessary step of CO2 hydrogenation to high value-added products, and regulating the selectivity of CO is still a fundamental challenge. In the present study, an efficient catalyst (CuZnNx@C-N) composed by Zn single atoms and Cu clusters stabilized by nitrogen sites is reported. It contains saturated four-coordinate Zn-N4 sites and low valence CuNx clusters. Monodisperse Zn induces the aggregation of pyridinic N to form Zn-N4 and N4 structures, which show strong Lewis basicity and has strong adsorption for *CO2 and *COOH intermediates, but weak adsorption for *CO, thus greatly improves the CO2 conversion and CO selectivity. The catalyst calcined at 700 °C exhibits the highest CO2 conversion of 43.6% under atmospheric pressure, which is 18.33 times of Cu-ZnO and close to the thermodynamic equilibrium conversion rate (49.9%) of CO2. In the catalytic process, CuNx not only adsorbs and activates H2, but also cooperates with the adjacent Zn-N4 and N4 structures to jointly activate CO2 molecules and further promotes the hydrogenation of CO2. This synergistic mechanism will provide new insights for developing efficient hydrogenation catalysts. 相似文献
158.
Shi Fang Liuan Li Danhao Wang Wei Chen Yang Kang Weiyi Wang Xin Liu Yuanmin Luo Huabin Yu Haochen Zhang Muhammad Hunain Memon Wei Hu Jr-Hau He Chen Gong Chengjie Zuo Sheng Liu Haiding Sun 《Advanced functional materials》2023,33(37):2214408
Underwater optical communication (UOC) has attracted considerable interest in the continuous expansion of human activities in marine/ocean environments. The water-durable and self-powered photoelectrodes that act as a battery-free light receiver in UOC are particularly crucial, as they may directly face complex underwater conditions. Emerging photoelectrochemical (PEC)-type photodetectors are appealing owing to their intrinsic aqueous operation characteristics with versatile tunability of photoresponses. Herein, a self-powered PEC photodetector employing n-type gallium nitride (GaN) nanowires as a photoelectrode, which is decorated with an iridium oxide (IrOx) layer to optimize charge transfer dynamics at the GaN/electrolyte interface, is reported. Strikingly, the constructed n-GaN/IrOx photoelectrode breaks the responsivity-bandwidth trade-off limit by simultaneously improving the response speed and responsivity, delivering an ultrafast response speed with response/recovery times of only 2 µs/4 µs while achieving a high responsivity of 110.1 mA W−1. Importantly, the device exhibits a large bandwidth with 3 dB cutoff frequency exceeding 100 kHz in UOC tests, which is one of the highest values among self-powered photodetectors employed in optical communication system. 相似文献
159.
Junwei Xiang Chuanzhou Han Jianhang Qi Yanjie Cheng Kai Chen Yongming Ma Jiayu Xie Yue Hu Anyi Mei Yinhua Zhou Hongwei Han 《Advanced functional materials》2023,33(25):2300473
Due to the low cost and excellent potential for mass production, printable mesoscopic perovskite solar cells (p-MPSCs) have drawn a lot of attention among other device structures. However, the low open-circuit voltage (VOC) of such devices restricts their power conversion efficiency (PCE). This limitation is brought by the high defect density at perovskite grain boundaries in the mesoporous scaffold, which results in severe nonradiative recombination and is detrimental to the VOC. To improve the perovskite crystallization process, passivate the perovskite defects, and enhance the PCE, additive engineering is an effective way. Herein, a polymeric Lewis base polysuccinimide (PSI) is added to the perovskite precursor solution as an additive. It improves the perovskite crystallinity and its carbonyl groups strongly coordinate with Pb2+, which can effectively passivate defects. Additionally, compared with its monomer, succinimide (SI), PSI serves as a better defect passivator because the long-chained macromolecule can be firmly anchored on those defect sites and form a stronger interaction with perovskite grains. As a result, the champion device has a PCE of 18.84%, and the VOC rises from 973 to 1030 mV. This study offers a new strategy for fabricating efficient p-MPSCs. 相似文献
160.
Rui Zhang Pengyu Zang Dan Yang Jiahao Li Narisu Hu Songnan Qu Piaoping Yang 《Advanced functional materials》2023,33(25):2300522
The sensitization performance of sonosensitizers plays a key role in the sonodynamic therapy (SDT) effect. Herein, ZnSnO3:Nd nanoparticles with R3c phase/amorphous heterogeneous structure are developed by phase engineering strategy and applied as an ideal sonosensitizer. In the crystalline perovskite-type ZnSnO3:Nd, the substitution of the Zn2+ with Nd3+ causes the O 2p non-bonded state to move toward the Fermi level, which optimizes the band structure for ultrasound sensitization by reducing bandgap. Meanwhile, the unequal charge substitution can also form electron traps and oxygen vacancies to shorten the electron migration distance, which accelerates the electron–hole separation and inhibits carrier recombination, thus improving the acoustic sensitivity. Moreover, the dangling bonds exposed on the surface of amorphous ZnSnO3:Nd provide more active sites, and the localized states of the amorphous phase may also promote carrier separation, resulting in synergistic SDT effect. In particular, the Zn2+ released from ZnSnO3:Nd in the acidic tumor microenvironment (TME) reduces the adenosine triphosphate production by inhibiting the electron transport chain , which promotes the tumor cell apoptosis through destroying the redox balance of TME. Combining the inherent second near infrared and computed tomography imaging capabilities, this ZnSnO3:Nd nanoplatform shows a promising perspective in clinic SDT field. 相似文献