排序方式: 共有42条查询结果,搜索用时 15 毫秒
1.
炭黑负载Pt-Sn双金属催化剂对乙醇的电催化氧化性能 总被引:2,自引:0,他引:2
采用一步还原法(乙二醇为还原剂)与两步还原法(在聚乙烯吡咯烷酮PVP保护下,先用硼氢化钠还原制备Sn溶胶,沉积Pt后用乙二醇还原)制备了炭黑负载Pt-Sn双金属催化剂,利用循环伏安法和计时电流法考察了催化剂制备方法、Pt/Sn原子比、溶液p H值、PVP/Sn质量比、反应介质等对乙醇室温电催化氧化活性和稳定性的影响.以X光衍射、透射电镜及电化学活性面积测定对所得催化剂进行了表征.发现引入Sn明显提高了Pt催化剂对乙醇的电催化活性与稳定性,两步还原法得到的Pt3Sn/C催化剂具有更小的颗粒尺寸,更大的电化学活性面积及更高的乙醇氧化活性与稳定性.与酸性介质相比,该催化剂在碱性介质中的电化学活性更好. 相似文献
2.
3.
1引言 煤是我国的主要能源,经燃烧炉排放的砷,硒等易挥发元素对大气产生较严重污染但因煤的成分复杂特殊,且砷,硒含量较低,试样处理及分析测试均较困难。本文研究使用了烧结分解法分解砷,湿法 HF+ HNO3+ HClO3分解硒后采用氢化物-电感耦合等离子体发射光谱法(HG-ICP-AIS)测定。结果令人满意。2实验部分2.1主要试剂与仪器美国 Thermo Jarrell Ash公司 Trace Scan电感耦合等离子体发射光谱仪和 T-PHD氢化物发生器。砷(Ⅲ),硒(Ⅳ)标准溶液,艾氏剂,1.5%硼氢化… 相似文献
4.
利用自行设计组装的以白色发光二极管为光源的表面等离子体子共振传感器实验装置, 检测了不同材质包裹的磁性纳米粒子连接靶向DNA与生物素化DNA探针的结合程度. 结果表明, 与聚苯乙烯磁性微球连接的靶向DNA相比, Fe3O4@SiO2核壳式纳米微球连接的靶向DNA与生物素化的DNA探针结合速率较快, 且其相对标准偏差较小. 相似文献
5.
4种动物药水提液中3种嘌呤碱HPLC法测定 总被引:1,自引:0,他引:1
以甲醇/水为流动相,反相高效液相色谱-紫外检测器测定了乌蛇、蟾蜍、土虫、地龙水提取液中黄嘌呤、次黄嘌呤、腺嘌呤的含量,对样品提取和高效液相色谱条件进行了优化。 黄嘌呤、次黄嘌呤、腺嘌呤的检出限分别为0.012×10-6、0.041×10-6、0.042×10-6 g/mL,样品分析的日内测定相对标准偏差分别小于4.1%、7.3%、4.5%,日间测定相对标准偏差分别小于5.8%、2.9%、3.1%,平均加标回收率为94%~107%。 相似文献
6.
7.
Xian-Jia Wang 《中国物理 B》2022,31(8):80204-080204
Having a large number of timely donations during the early stages of a COVID-19 breakout would normally be considered rare. Donation is a special public goods game with zero yield for donors, and it has the characteristics of the prisoners' dilemma. This paper discusses why timely donations in the early stages of COVID-19 occurred. Based on the idea that donation is a strategy adopted by players during interconnection on account of their understanding of the environment, donation-related populations are placed on social networks and the inter-correlation structures in the population are described by scale-free networks. Players in donation-related populations are of four types: donors, illegal beneficiaries, legal beneficiaries, and inactive people. We model the evolutionary game of donation on a scale-free network. Donors, illegal beneficiaries and inactive people learn and update strategies under the Fermi update rule, whereas the conversion between legal beneficiaries and the other three types is determined by the environment surrounding the players. We study the evolution of cooperative action when the agglomeration coefficient, the parameters of the utility function, the noise intensity, the utility coefficient, the donation coefficient and the initial states of the population on the scale-free network change. For population sizes of 50, 100, 150, and 200, we give the utility functions and the agglomeration coefficients for promoting cooperation and study the corresponding steady states and structural characteristics of the population. We identify the best ranges of the noise intensity K, the donation coefficient α and the utility coefficient β for promoting cooperation at different population sizes. Furthermore, with the increase of the population size, the donor traps are found. At the same time, it is discovered that the initial states of the population have a great impact on the steady states; thus the upper and lower triangle phenomena are proposed. We also find that the population size itself is also an important factor for promoting donation, pointing out the direction of efforts to further promote donation and achieve better social homeostasis under the donation model. 相似文献
8.
附着性能优异的碳对电极的制备及其在染料敏化太阳能电池中的应用 总被引:1,自引:0,他引:1
通过引入一种低成本商业导电碳浆(CC)作为粘结剂, 以色素碳黑(Cb)作为催化材料, 成功制备了Cb-CC对电极. 着重解决传统碳对电极的主要问题, 即碳与导电基底的附着力问题. 附着力测试结果表明: CC的引入改善了Cb与导电基板之间的附着力, 同时增强了碳对电极的导电性和稳定性. 扫描电镜(SEM)结果显示, CC与Cb混合后, 碳膜的多孔结构依然存在, 即这种对电极能同时增加导电性和催化活性. 采用循环伏安(CV)和电化学阻抗谱(EIS)对Cb-CC对电极的催化活性进行了研究. 光电性能测试结果表明, 基于Cb-CC染料敏化太阳能电池(DSSC)的能量转换效率达到了6.54%, 进一步优化后, 当Cb和CC的质量比为23:77 时效果最佳, 达到最高效率6.81%. 此外, 基于Cb-CC的DSSC长期稳定性测试结果表明, 700 h后各项光电参数无明显下降. 该实验成果为增强整体电池的稳定性和促进低成本DSSC产业化奠定了基础. 相似文献
9.
建立离子色谱-抑制型电导检测牛肝菌中胆碱、腐胺和尸胺的方法。牛肝菌干片样品经7 mmol/L甲烷磺酸溶液提取,过滤膜,经反相固相萃取柱净化后进样分析。胆碱、腐胺、尸胺与样品中共存离子在IonPac CS17(250mm×4 mm)阳离子交换色谱柱上可实现较好分离。以7 mmol/L甲烷磺酸为淋洗液等度淋洗, 25 min可完成一次样品测定。胆碱、腐胺和尸胺的检出限(S/N=3)分别为0. 002、0. 002和0. 003 mg/L,具有较宽的线性范围(0. 01~10 mg/L),样品加标回收率为91. 6%~100. 2%。该方法简便、选择性好、灵敏度高,适用于牛肝菌中胆碱、腐胺和尸胺的检测分析。 相似文献
10.