Effects of current density, duty cycle and frequency on microstructure and particles content of electrodeposited Co-BN （hexagonal） nano composite coatings were analyzed by SEM, FESEM, EDS, AFM and XRD techniques. Th...Effects of current density, duty cycle and frequency on microstructure and particles content of electrodeposited Co-BN （hexagonal） nano composite coatings were analyzed by SEM, FESEM, EDS, AFM and XRD techniques. The microhardness, tribological behavior and wear mechanism were also investigated. Generally, as the current density and frequency increased, the particles content and microhardness of the coatings increased firstly and then decreased. Moreover, by reducing duty cycle, more particles were incorporated and higher microhardness was obtained. The best tribological behavior was achieved under the conditions duty cycle of 10%, frequency of 50 Hz and current density of 100 mA/cm2.展开更多
目的对中枢性性早熟儿童心理社会状态的相关研究进行范围综述,以期为今后的干预提供参考。方法系统检索建库至2022年9月Web of Science、PubMed、MEDLINE、Cochrane Library、美国临床试验数据库、美国食品药品监督管理局网站、中国生...目的对中枢性性早熟儿童心理社会状态的相关研究进行范围综述,以期为今后的干预提供参考。方法系统检索建库至2022年9月Web of Science、PubMed、MEDLINE、Cochrane Library、美国临床试验数据库、美国食品药品监督管理局网站、中国生物医学文献数据库、中国知网、维普、万方数据库的文献,筛选对中枢性性早熟儿童的心理状态、感受、经历等进行研究的文献,对纳入文献进行Meta分析。结果最终纳入19篇文献,发表国家分别为中国(12篇)、美国(2篇)、比利时(2篇)、韩国(2篇)、土耳其(1篇);研究对象为女童的有14篇。11篇采用Achenbach儿童行为量表(CBCL)、3篇采用儿童生存质量普适性核心量表(Peds QL 4.0)、3篇采用长处与困难问卷(SDQ)评价。结论中枢性性早熟对儿童心理社会状况均存在不同程度的影响。而目前针对中枢性性早熟女童的研究较多,鲜有报道中枢性性早熟男童和外周性性早熟儿童的研究。目前缺乏有效的工具来测量中枢性性早熟儿童的健康相关生活质量,因此限制了中枢性性早熟对健康相关生活质量影响的研究。还需要进一步的研究来评估中枢性性早熟儿童的健康相关生活质量是否随着治疗而改善。展开更多
文摘Effects of current density, duty cycle and frequency on microstructure and particles content of electrodeposited Co-BN （hexagonal） nano composite coatings were analyzed by SEM, FESEM, EDS, AFM and XRD techniques. The microhardness, tribological behavior and wear mechanism were also investigated. Generally, as the current density and frequency increased, the particles content and microhardness of the coatings increased firstly and then decreased. Moreover, by reducing duty cycle, more particles were incorporated and higher microhardness was obtained. The best tribological behavior was achieved under the conditions duty cycle of 10%, frequency of 50 Hz and current density of 100 mA/cm2.
