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71.
目的评价氩激光联合活血散瘀中药治疗视网膜分支静脉阻塞的临床疗效。方法氩激光联合活血散瘀中药治疗组40眼和单纯氩激光治疗组30眼,随访6~12月,观察视力、视网膜出血和黄斑水肿变化并行统计分析。结果联合中药治疗组患者和单纯氩激光光凝组治疗前后视力均有显著差异(P<0.05),治疗后两组最后视力比较差异显著(P<0.05),前者较后者视力进步明显。而且联合中药治疗出血吸收情况明显优于前组(P<0.05),并且两组黄斑水肿发生率治疗前后均有显著差异(P<0.05),虽然治疗6月后两组黄斑水肿发生率无显著差异(P>0.05),但后者较前者发生率低。结论氩激光光凝联合活血散瘀中药治疗更能促使视网膜分支静脉阻塞患者的出血吸收、黄斑水肿减轻及视功能的改善,在总体上取得了更好的治疗效果。 相似文献
72.
We have constructed a series of new code families for the spectral-amplitude-coding optical code-division multiple-access (CDMA) system, and proposed new transmitter and receiver structures based on tunable chirped fiber Bragg gratings (FBGs). The proposed system has been analyzed by taking into account the effects of phase-induced intensity noise, shot noise, and thermal noise. We have also compared the performance of this system with that of a former system where a Hadamard code is used. It has been shown that the new code families can suppress the intensity noise effectively and improve the system performance significantly. When the effective power is large (i.e., >-10 dBm), the intensity noise is the main factor that limits the system performance. When the effective power is not sufficiently large, thermal and shot noise sources become the main limiting factors and the effect of thermal noise is much larger than that of shot noise 相似文献
73.
Xinzhen Lu Yifeng Cheng Menghao Li Yucheng Zou Cheng Zhen Duojie Wu Xianbin Wei Xiangyan Li Xuming Yang Meng Gu 《Advanced functional materials》2023,33(12):2212847
Solid-state lithium metal batteries (SSLMBs) are a promising candidate for next-generation energy storage systems due to their intrinsic safety and high energy density. However, they still suffer from poor interfacial stability, which can incur high interfacial resistance and insufficient cycle lifespan. Herein, a novel poly(vinylidene fluoride‑hexafuoropropylene)-based polymer electrolyte (PPE) with LiBF4 and propylene carbonate plasticizer is developed, which has a high room-temperature ionic conductivity up to 1.15 × 10−3 S cm−1 and excellent interfacial stability. Benefitting from the stable interphase, the PPE-based symmetric cell can operate for over 1000 h. By virtue of cryogenic transmission electron microscopy (Cryo-TEM) characterization, the high interfacial compatibility between Li metal anode and PPE is revealed. The solid electrolyte interphase is made up of an amorphous outer layer that can keep intimate contact with PPE and an inner Li2O-dominated layer that can protect Li from continuous side reactions during battery cycling. A LiF-rich transition layer is also discovered in the region of PPE close to Li metal anode. The feasibility of investigating interphases in polymer-based solid-state batteries via Cryo-TEM techniques is demonstrated, which can be widely employed in future to rationalize the correlation between solid-state electrolytes and battery performance from ultrafine interfacial structures. 相似文献
74.
Ultra-Stable and Sensitive Ultraviolet Photodetectors Based on Monocrystalline Perovskite Thin Films
Xu Li Chang Liu Feng Ding Zheyi Lu Peng Gao Ziwei Huang Weiqi Dang Liqiang Zhang Xiaohui Lin Shuimei Ding Bailing Li Ying Huangfu Xiaohua Shen Bo Li Xuming Zou Yuan Liu Lei Liao Yiliu Wang Xidong Duan 《Advanced functional materials》2023,33(15):2213360
The detection of ultraviolet (UV) radiation with effective performance and robust stability is essential to practical applications. Metal halide single-crystal perovskites (ABX3) are promising next-generation materials for UV detection. The device performance of all-inorganic CsPbCl3 photodetectors (PDs) is still limited by inner imperfection of crystals grown in solution. Here wafer-scale single-crystal CsPbCl3 thin films are successfully grown by vapor-phase epitaxy method, and the as-constructed PDs under UV light illumination exhibit an ultralow dark current of 7.18 pA, ultrahigh ON/OFF ratio of ≈5.22 × 105, competitive responsivity of 32.8 A W−1, external quantum efficiency of 10867% and specific detectivity of 4.22 × 1012 Jones. More importantly, they feature superb long-term stability toward moisture and oxygen within twenty-one months, good temperature tolerances at low and high temperatures. The ability of the photodetector arrays for excellent UV light imaging is further demonstrated. 相似文献
75.
Zepan Wang Peiyuan Wu Xubing Zou Sheng Wang Lei Du Ting Ouyang Zhao-Qing Liu 《Advanced functional materials》2023,33(16):2214275
By using the more electro-negative Mn3+ ion to partially replace Co3+ at the octahedral site of spinel ZnCo2O4, i.e., forming ternary Zn–Mn–Co spinel oxide, the electrocatalytic oxygen reduction/evolution activity is found to be significantly increased. Considering the physical characterization and theoretical calculations, it demonstrated that the bond competition played a key role in regulating the cobalt valence state and the electrocatalytic activity. The partial replacement of octahedral-site-occupied Co3+ by Mn3+ can effectively modulate the adjacent Co–O bond and induce the Jahn–Teller effect, thus changing the originally stable crystal structure and optimizing the binding strength between the active center and reaction intermediates. Certainly, the Mn-substituted ZnMn1.4Co0.6O4/NCNTs exhibit higher electrocatalytic oxygen reduction reaction (ORR) activity than that of ZnCo2O4/NCNTs and ZnMn2O4/NCNTs, supporting that the Co–O bond covalency determines the ORR activity of spinel ZnCo2O4. This study offers the competition between adjacent Co–O and Mn–O bonds via the BOh–O–BOh edge-sharing geometry. The ion substitution at octahedral sites by less electronegative cations can be a new and effective way to improve the electrocatalytic performance of cobalt-based spinel oxides. 相似文献
76.
Guodong Xu Ji Pan Xiuyang Zou Zhiyu Jin Jiale Zhang Pengda Fang Qiuhuan Zhang Zhe Sun Feng Yan 《Advanced functional materials》2023,33(35):2302364
The performance of alkaline fuel cells is severely limited by substandard anion exchange membranes (AEMs) due to the lower ionic conductivity compared to the proton exchange membranes. The ionic conductivity of AEMs can be effectively improved by regulating the microphase structure, but it still cannot meet the practical use requirements. Here, enhanced microphase-separated structures are constructed by the cooperativity of highly hydrophilic dual cations and highly hydrophobic fluorinated side chains. Meanwhile, the introduction of O enhances the flexibility of side chains and facilitates the formation of ion transport channels. The dual piperidinium cation functionalized membrane (PB2Pip-5C8F) which is grafted with the ultra-hydrophobic fluorocarbon chain exhibits a high conductivity of 74.4 mS cm−1 at 30 °C and 168.46 mS cm−1 at 80 °C. Furthermore, the PB2Pip-5C8F membrane achieves the highest peak power density of 718 mW cm−2 at 80 °C under a current density of 1197 mA cm−2 without back pressure. A long-term life cell test of this AEM shows a low voltage decay rate of 1.68 mV h−1 over 70 h of operation at 80 °C. 相似文献
77.
本文以三角波为传输波变形,以差分双相码为基础提出了一种新型的线路码-MT-2B2B。文章描述了码的构成,计算了码的频谱结构,分析了码的特点。码对于高速近距离基带传输系统具有较大的实用价值。 相似文献
78.
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80.
Haijun Tan Chunyue Pan Gang Wang Yingying Wu Yiping Zhang Yingping Zou Guipeng Yu Min Zhang 《Organic Electronics》2013,14(11):2795-2801
A series of organic dyes (POZ-2, POZ-3, POZ-4 and POZ-5) involving phenoxazine were synthesized as sensitizers for application in dye-sensitized solar cells (DSSCs). For comparison, three different electron donors namely 10-phenyl-10H-phe-nothiazine, 10-phenyl-10H-phenoxazine and triphenylamine were separately appended onto the 7-position of the model dye (POZ-2). The obtained four dyes exhibit considerably high values of conversion efficiencies of 6.6%, 7.8%, 7.1% and 6.4%, respectively, under the simulated AM1.5G conditions. The geometries of the dyes were optimized to gain insight into the molecular structure and electron distribution, and then the charge extraction and transient photovoltage decay measurements were further performed to understand the influence of electron donors on the photovoltaic behaviors. 相似文献