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71.
采用喷雾干燥法合成了Na3V2(PO4)3(NVP)前驱体,然后经过高温煅烧得到水系锌离子电池正极复合材料Na3V2(PO4)3/C(NVP/C),考察了煅烧温度和煅烧时间对NVP/C性能的影响。通过XRD、SEM和BET对样品结构和形貌进行了表征,通过循环伏安和充放电测试了样品的电化学性能。结果表明,不同煅烧温度和煅烧时间制备样品均为纯相的NVP/C,且并没有改变NVP/C的晶体结构;煅烧温度过高或煅烧时间过长会导致晶粒尺寸增大,性能迅速衰减。NVP/C制备最佳条件为煅烧温度700℃、煅烧时间8 h,在该条件下所制备的NVP/C(记为NVP/C-700-8)形貌更为规整,结晶性良好,具有较小的阻抗以及更好的离子扩散能力,进而表现出最佳的电化学性能。在0.1 A/g电流密度下表现出最佳的放电比容量(122.4 mA·h/g)。在1.0 A/g电流密度下经过200圈循环后放电比容量仍高达103.9 mA·h/g。 相似文献
72.
以DMY为基底物、Na2SeO3为硒化剂制备硒化DMY。采用UV、FTIR、NMR、XRD、TG、原子荧光光度计表征其结构和性能,CCK-8法检测对HSC-3细胞增殖的影响,划痕实验研究对HSC-3细胞迁移的影响。结果表明,硒化DMY中仍存在黄酮基本母核、并新形成C-Se键,其中硒含量为6.54%±0.22%;DMY和硒化DMY均对HSC-3细胞的增殖和迁移有良好的抑制作用、抑制效果与浓度呈正相关,且DMY和硒化DMY对HSC-3细胞的半数抑制浓度(IC50)分别为25.27 μg/mL、21.27 μg/mL,DMY的硒化有效提高了对HSC-3细胞增殖和迁移的抑制能力。 相似文献
73.
目的观察早期静脉注射特布他林注射液对大鼠急性肺损伤(ALI)的影响。方法将40只SD大鼠随机分为4组:生理盐水对照组(A组)、ALI组(B组)、ALI+特布他林治疗组(C组)、ALI+特布他林+哇巴因干预组(D组),每组10只。各组大鼠分别以10%水合氯醛3.5uL·g-1腹腔麻醉。麻醉成功后,A组大鼠采用尾静脉注射生理盐水5mg·kg-1,1h内注完;B组大鼠采用尾静脉注射脂多糖(LPS)5mg·kg-1(融于1mL生理盐水中),分4次给药,1h内注完;C、D2组大鼠采用尾静脉注射LPS5mg·kg-1(融于1mL生理盐水中),分4次给药,1h内注射完后,再注射硫酸特布他林注射液5.0uL·g-1体质量,1h内注射完后。然后将大鼠头部抬高45°,光源照射颈部直视下行气管插管,插管成功后,A、B、C3组气管内滴注林格氏液1mL·kg-1,D组气管内滴注含哇巴因10-3mol·L-1的林格氏液1mL·kg-1通过建立LPS诱导的大鼠急性肺损伤模型,对各组大鼠肺组织病理学评分,观察各组大鼠的肺湿干重比(W/D)、肺组织Na+-K+-ATP酶的活性,并测定各组大鼠肺泡灌洗液中的细胞数、中性粒细胞计数及蛋白含量。结果A组肺组织病理学评分值、W/D值、细胞计数、中性粒细胞百分比、蛋白含量均明显低于B、C、D3组(均P〈0.05),B、D2组上述指标均明显高于C组(均P〈0.05),B组上述指标与D组比较差异无统计学意义(P〉0.05)。A组肺组织Na+-K+-ATP酶的活性明显高于B、C、D3组(P〈0.05),B、D2组均明显低于C组(均P〈0.05),B组与D组比较差异无统计学意义(P〉0.05)。结论早期静脉注射特布他林可通过上调肺组织Na+K+-ATP酶的活性来促进肺泡上皮细胞对液体重吸收,从而控制大鼠急性肺损伤的进展。 相似文献
74.
75.
DING Yimin HOU Na CHEN Nianyi XIA Yiben 《稀有金属(英文版)》2006,25(4):316-320
The phase diagrams of the Li2MoO4-Na2MoO4 and Na2MoO4-K2MoO4 systems have been reassessed using differential thermal analysis together with high-temperature and room-temperature X-ray diffraction analysis. The results showed that the compound Li2MoO4.6Na2MoO4 did not exist; however, it confirmed the existence of the compound Li2MoO4.3Na2MoO4 in the Li2MoO4-Na2MoO4 systen'ls. With regard to the system of Na2MoO4-K2MoO4, we could not confirm the results reported by Bukhanova who claimed that the system was eutectic type with 1:1 and 1:2 intermediate compounds, refuting the statement of Amadori who thought there was an apparent phase boundary at high temperature in α-solid solution region of the Na2MoO4-K2MoO4 binary system. The revised phase diagrams of these systems are illustrated in this article. These experimental results are in agreement with the computerized prediction using the support vector machine-atomic parameter method for the assessment of phase diagrams. 相似文献
76.
Na2SO4溶液中磷酸环己胺的缓蚀机理及其吸附与脱附行为 总被引:10,自引:1,他引:10
应用极化曲线和交流阻抗技术研究了磷酸环己胺在Na2OS4溶液中的缓蚀机理及其吸附与脱附行为。结果表明,磷酸环己胺是一种负催化效应作用机理的阳极型缓蚀剂。它在铁电极上的吸附等温式符合Temkin模型。由于缓蚀剂的吸附与脱附作用,其阴极极化曲线存在着氧扩散极限电流区,强吸附区和Tefel线性区,而阳极极化曲线存在着Tafek线性区,脱附区和无缓蚀区。 相似文献
77.
Oxide coatings on AM60B magnesium alloy were prepared using the microarc oxidation(MAO) technique in silicate-KOH electrolyte with addition of 0-6.0 g/L Na2WO4. The MAO processes in base electrolyte with different concentrations of Na2WO4 were studied. The microstructure, compositions and mechanical tribological characteristics of the oxide coatings were also investigated by SEM, XRD, XPS, microhardness analysis and ball-on-disc friction testing, respectively. It is found that the addition of Na2WO4 into the base electrolyte has direct effect on the characteristics of voltage-time curves and breakdown voltage in MAO process. The number of micropores at top of the coating surface is increased by the addition of Na2WO4. The fraction of forsterite Mg2SiO4 in the oxide coating increases with increasing concentration of Na2WO4 in base electrolytes. Furthermore, the microhardness and wear resistance of oxide coatings are enhanced as well. 相似文献
78.
Jun Nakamura Yuusuke Maruyama Genichi Tajima Makiko Suwa Chikara Sato 《International journal of molecular sciences》2022,23(6)
The Ca2+-ATPase is an integral transmembrane Ca2+ pump of the sarcoplasmic reticulum (SR). Crystallization of the cytoplasmic surface ATPase molecules of isolated scallop SR vesicles was studied at various calcium concentrations by negative stain electron microscopy. In the absence of ATP, round SR vesicles displaying an assembly of small crystalline patches of ATPase molecules were observed at 18 µM [Ca2+]. These partly transformed into tightly elongated vesicles containing ATPase crystalline arrays at low [Ca2+] (≤1.3 µM). The arrays were classified as ‘’tetramer’’, “two-rail” (like a railroad) and ‘’monomer’’. Their crystallinity was low, and they were unstable. In the presence of ATP (5 mM) at a low [Ca2+] of ~0.002 µM, “two-rail” arrays of high crystallinity appeared more frequently in the tightly elongated vesicles and the distinct tetramer arrays disappeared. During prolonged (~2.5 h) incubation, ATP was consumed and tetramer arrays reappeared. A specific ATPase inhibitor, thapsigargin, prevented both crystal formation and vesicle elongation in the presence of ATP. Together with the second part of this study, these data suggest that the ATPase forms tetramer units and longer tetramer crystalline arrays to elongate SR vesicles, and that the arrays transform into more stable “two-rail” forms in the presence of ATP at low [Ca2+]. 相似文献
79.
通过实验探讨了Na型蛭石在不同的Pb2 溶液浓度和不同的温度下的2Na =Pb2 离子交换动力学关系,实验结果表明:蛭石中2Na =Pb2 离子交换很快,0.5min以内交换吸附率已达70%~80%以上,达到交换平衡的时间与溶液的起始浓度和交换时的温度有关,原液浓度越大达到平衡所需要的时间越长,温度越高交换越快;蛭石中2Na =Pb2 离子交换过程受粒内扩散控制;动力学方程符合克-金-布扩散(粒内扩散)方程;计算出了蛭石中2Na =Pb2 离子交换过程的表观活化能E'a的平均值为25.21kJ/mol;推导出了蛭石中2Na =Pb2 离子交换过程的动力学方程为:1-2/3α-(1-α)2/3=k0r-20exp-(25.21/R)·1/Tt 相似文献
80.
Manabu Nishijima Irina D. Gocheva Shigeto Okada Takayuki Doi Jun-ichi Yamaki Tetsuaki Nishida 《Journal of power sources》2009,190(2):558-562
Fluorine compounds have high discharge voltage due to its highly ionic metal-ligand bonds. In them, perovskite-type metal trifluorides with corner sharing matrix have large bottlenecks of diffusion pathways for intercalants. Iron trifluoride composites (FeF3-C) prepared by planetary ball milling with carbon showed reversible charge/discharge behavior not only for Li, but also for Na anodes. X-ray diffraction and 57Fe Mössbauer spectroscopy were applied to characterize the electrochemical properties of FeF3 vs. Li and Na anodes. The cathode performances of the other commercially available transition metal trifluorides such as MF3 (M = Ti, V, Mn, Co) have been also investigated. 相似文献