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11.
Six new 1,3,4-thiadiazole Schiff base derivatives were synthesized and characterized by IR spectroscopy and ~1H NMR spectrometry, and their anti-corrosion properties and thermal stability were investigated via thermogravimetric analysis(TGA) and copper strip corrosion test. The tribological behavior of the said Schiff base derivatives was evaluated on an Optimol SRV~?4 oscillating reciprocating friction and wear tester. The worn surfaces of the steel discs were investigated using a scanning electron microscope(SEM) and energy dispersive X-ray spectrometer(EDS). The test results indicated that these thiadiazole Schiff base derivatives possessed favourable thermal stability, corrosion inhibiting ability and the capability of improving the tribological characteristic of the base oil effectively. It is assumed that the adsorbed additives probably reacted with the steel surfaces during the friction process, resulting in the formation of a protective film composed of sulphates, sulphides and organic nitrogen compounds. 相似文献
12.
K. Zhang W.P. Shen C.C. Ge 《金属学报(英文版)》2007,20(1):59-64
W / Cu functionally gradient materials (FGMs) containing 1%La_2O_3 and 1%TiC were prepared using graded sintering under ultra-high pressure (GSUHP). The specimens have been found to exhibit low porosity (11.57% and 11.35%, respectively). Shearing strength of the specimens between layers is good. Moreover, the specimens have still demonstrated good performance in testing thermal-shock resistance. When power density of laser is 200MWm~(-2), the specimens have been tested for thermal-shock resistance (1000 times); the specimens that contained 1%La_2O_3 were not subjected to damage, whereas those that contained 1%TiC began to crack. Finally, effect of additives on thermal-shock resistance was also preliminarily discussed. 相似文献
13.
Wandi Wahyudi Viko Ladelta Leonidas Tsetseris Merfat M. Alsabban Xianrong Guo Emre Yengel Hendrik Faber Begimai Adilbekova Akmaral Seitkhan Abdul-Hamid Emwas Mohammed N. Hedhili Lain-Jong Li Vincent Tung Nikos Hadjichristidis Thomas D. Anthopoulos Jun Ming 《Advanced functional materials》2021,31(23):2101593
Electrolyte additives have been widely used to address critical issues in current metal (ion) battery technologies. While their functions as solid electrolyte interface forming agents are reasonably well-understood, their interactions in the liquid electrolyte environment remain rather elusive. This lack of knowledge represents a significant bottleneck that hinders the development of improved electrolyte systems. Here, the key role of additives in promoting cation (e.g., Li+) desolvation is unraveled. In particular, nitrate anions (NO3−) are found to incorporate into the solvation shells, change the local environment of cations (e.g., Li+) as well as their coordination in the electrolytes. The combination of these effects leads to effective Li+ desolvation and enhanced battery performance. Remarkably, the inexpensive NaNO3 can successfully substitute the widely used LiNO3 offering superior long-term stability of Li+ (de-)intercalation at the graphite anode and suppressed polysulfide shuttle effect at the sulfur cathode, while enhancing the performance of lithium–sulfur full batteries (initial capacity of 1153 mAh g−1 at 0.25C) with Coulombic efficiency of ≈100% over 300 cycles. This work provides important new insights into the unexplored effects of additives and paves the way to developing improved electrolytes for electrochemical energy storage applications. 相似文献
14.
本文重点解读通信电源用交联聚烯烃绝缘电缆通信行业标准的主要内容,介绍了交联聚烯烃绝缘的技术特点.评述了聚氯乙烯(PVC)绝缘电缆在环保和安全方面存在的不足.通过比较说明了交联聚烯烃绝缘电缆相对于PVC绝缘电缆和非交联的无卤低烟阻燃聚烯烃绝缘电缆所具有的优势.本文还介绍了低压电缆制造技术,特别是交联工艺路线、电缆料添加剂及电缆料配混技术进展等方面的内容,对未来通信电源用电缆的发展以及标准修改内容提出了建议. 相似文献
15.
16.
文章主要就普通垂直电镀设备下0.15mm的微盲孔电锡蚀刻保护工艺进行阐述,详细讲述了该工艺条件下的工艺参数控制。 相似文献
17.
Shucheng Qin Zhenrong Jia Lei Meng Can Zhu Wenbin Lai Jinyuan Zhang Wenchao Huang Chenkai Sun Beibei Qiu Yongfang Li 《Advanced functional materials》2021,31(25):2102361
Organic solar cells (OSCs) have recently reached a remarkably high efficiency and become a promising technology for commercial application. However, OSCs with top efficiency are mostly processed by halogenated solvents and with additives that are not environmentally friendly, which hinders large-scale manufacture. In this study, high-performance tandem OSCs, based on polymer donors and two small-molecule acceptors with different bandgaps, are fabricated by solution processing with non-halogenated solvents without additive. Importantly, the two active layers developed from non-halogenated solvents show better phase segregation and charge transport properties, leading to superior performance than halogenated ones. As a result, a tandem OSC with high efficiency of up to 16.67% is obtained, showing unique advantages in future massive production. 相似文献
18.
Zixiang Liu Rui Wang Yuchen Gao Shilin Zhang Jiandong Wan Jianfeng Mao Longhai Zhang Hongbao Li Junnan Hao Guanjie Li Lin Zhang Chaofeng Zhang 《Advanced functional materials》2023,33(49):2308463
The practicality of aqueous zinc ion batteries (AZIBs) for large-scale energy storage is hindered by challenges associated with zinc anodes. In this study, a low-cost and multi-function electrolyte additive, cetyltrimethyl ammonium bromide (CTAB), is presented to address these issues. CTAB adsorbs onto the zinc anode surface, regulating Zn2+ deposition orientation and inhibiting dendrite formation. It also modifies the solvation structure of Zn2+ to reduce water reactivity and minimize side reactions. Additionally, CTAB optimizes key physicochemical parameters of the electrolyte, enhancing the stability of the electrode/electrolyte interface and promoting reversibility in AZIBs. Theoretical simulations combined with operando synchrotron radiation-based in situ Fourier transform infrared spectra and in situ electrochemical impedance spectra further confirm the modified Zn2+ coordination environment and the adsorption effect of CTAB cations at the anode/electrolyte interface. As a result, the assembled Zn-MnO2 battery demonstrates a remarkable specific capacity of 126.56 mAh g−1 at a high current density of 4 A g−1 after 1000 cycles. This work highlights the potential of CTAB as a promising solution for improving the performance and practicality of AZIBs for large-scale energy storage applications. 相似文献
19.
在硅磷酸铝反应物凝胶中采用引入钯盐共晶化的方法,一步合成了PdSAPO-5分子筛。通过不同温度的水热处理来对分子筛材料进行改性,用扫描电子显微镜观察处理前后样品的晶形变化,用EDS分析不同晶粒上的元素组成。 相似文献
20.
Jianyu Yuan Zhichun Zhai Huilong Dong Jing Li Zuoquan Jiang Youyong Li Wanli Ma 《Advanced functional materials》2013,23(7):885-892
A series of polymers containing benzo[1,2‐b:4,5‐b′]dithiophene and N‐alkylthieno[3,4‐c]pyrrole‐4,6‐dione are designed. By incorporating different alkylthienyl side chains, the fill factor (FF) and open circuit voltage (Voc) of the copolymers are further improved. The experimental results and theoretical calculations show that the size and topology of the side chains can influence the polymer solubility, energy levels, and intermolecular packing by altering the molecular coplanarity. As a result of improved morphology and fine‐tuned energy levels, an increased FF and a high Voc of 1.00 V are achieved, as well as a power conversion efficiency of 6.17%, which is the highest efficiency ever reported for polymer solar cells with a Voc over 1 V. 相似文献