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Ti6Al4V磁控溅射沉积Ag-Cu涂层及其抗菌性能的研究
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作者 丁结平 丁佳 +1 位作者 高波 徐晋勇 《桂林电子科技大学学报》 2024年第3期274-280,共7页
钛合金作为植入物广泛应用于医学领域,由于不具备抗菌性能,易造成人体受到细菌感染,随着医用材料对抗菌性能要求的日益提升,亟待开展钛合金抗菌性能研究,以拓展其应用范围。为改善钛合金Ti6Al4V的抗菌性能,采用磁控溅射技术优化工艺参数... 钛合金作为植入物广泛应用于医学领域,由于不具备抗菌性能,易造成人体受到细菌感染,随着医用材料对抗菌性能要求的日益提升,亟待开展钛合金抗菌性能研究,以拓展其应用范围。为改善钛合金Ti6Al4V的抗菌性能,采用磁控溅射技术优化工艺参数,在钛合金Ti6Al4V表面制备Ag、Ag-Cu涂层,采用金相显微镜、扫描电子显微镜(SEM)、能谱分析(EDS)、X射线衍射仪(XRD)等表征手段对涂层的表面形貌、微观结构、化学成分分布等性能进行研究;通过体外抗菌活性试验对试样涂层进行抗菌性能检测。实验结果表明,溅射沉积Ag、Ag-Cu涂层对大肠杆菌和金黄色葡萄球菌的抑菌率均为99.99%。由于涂层析出的Ag^(+)、Cu^(2+)起到了抗菌作用,以及Ag、Ti粒子发生了光催化作用,产生了抗菌效果。 展开更多
关键词 磁控溅射 钛合金 ag-Cu涂层 ag涂层 抗菌
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银含量对快速热冲击下Sn−xAg−0.5Cu焊点显微组织和力学性能的影响
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作者 彭晨 王善林 +6 位作者 吴鸣 尹立孟 陈玉华 叶科江 陈维政 张体明 谢吉林 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第6期1922-1935,共14页
使用高频感应加热设备研究Ag含量对快速热冲击下Sn−xAg−0.5Cu焊点的显微组织和剪切强度的影响。结果表明,Ag含量的增加使焊点表面更致密光滑,减少焊点内部长条状Cu6Sn5金属间化合物(IMC)的产生,从而提高焊点的抗氧化性。Ag能够加快焊点... 使用高频感应加热设备研究Ag含量对快速热冲击下Sn−xAg−0.5Cu焊点的显微组织和剪切强度的影响。结果表明,Ag含量的增加使焊点表面更致密光滑,减少焊点内部长条状Cu6Sn5金属间化合物(IMC)的产生,从而提高焊点的抗氧化性。Ag能够加快焊点界面IMC层的生长速度,Cu6Sn5层的生长速度由体扩散和晶界扩散共同决定,Cu3Sn层的生长速度由体扩散和界面反应共同决定。在快速热冲击环境下,焊点的断裂模式从韧性断裂转变为脆性断裂,而高Ag含量使得焊点的断裂模式转变时间更短,降低焊点的抗热疲劳性能。 展开更多
关键词 ag含量 快速热冲击 Sn−ag−Cu 焊点 生长动力学 断裂模式
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Marriage-Age and Fertility Pattern among Reproductive Age Women in Abakaliki, Ebonyi State, South East Nigeria
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作者 Johnson Akuma Obuna Nkiruka Bridget Uche-Nwidagu 《Open Journal of Obstetrics and Gynecology》 2024年第9期1449-1462,共14页
Introduction: In Nigeria, one of the major reasons for marriage is procreation and married couples look forward to having children within a year or two of marriage. The age of marriage is on the increase in this part ... Introduction: In Nigeria, one of the major reasons for marriage is procreation and married couples look forward to having children within a year or two of marriage. The age of marriage is on the increase in this part of the world. Many women are now increasingly getting engulfed in career and academic pursuits at the detriment of early marriage. Many men are also not interested in marrying women who have no job. There is age-related acceleration of primordial follicle depletion which is of great clinical importance because it is associated with a significant decrease in fecundity. Objective: This study assessed the ages of the marriage of women who attended Fertility and Antenatal clinics at the National Obstetric Fistula Centre and Smile Specialist Hospital, Abakaliki, and their relationship with the fertility pattern of these women. Methods: This was a cross-sectional study of 352 consenting married women who sought and received fertility and Antenatal care at the National Obstetric Fistula Centre and Smile Specialist Hospital Abakaliki, South-East Nigeria between February 1, 2022 and January 31, 2024. Semi-structured questionnaires were administered to the participants over a two-year period. Data was analyzed using IBM SPSS version 20. A test of statistical significance was done using Chi Square. Results: The age group with the highest education was 26 - 30. This was statistically significant (X2 = 90.893, P-value 2 = 294.555, P-value 2 = 173.007, p-value 2 = 129.494, P-value 2 = 169.300, p-value 2 = 279.230, p-value Conclusion: There is increased difficulty at conception at marriage age above 25 years. The major reasons for delayed marriage were academic pursuit and lack of gainful employment. Education of the masses and inclusion of biological dynamics of the female reproductive behaviours as part of the core school curriculum will help enlighten the female and the male folks alike to enable them to make informed decisions with regard to the timing of marriage and commencement of procreation. This will help reduce infertility and save millions of couples the agony associated with infertility. 展开更多
关键词 FERTILITY Reproductive age Women Marriage-age Conception-age
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Strengthening Active Aging through Older People’s Association and Economic Activity of the Older People in Nepal
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作者 Hom Nath Chalise James Brightman 《Advances in Aging Research》 CAS 2024年第2期15-24,共10页
Aging is a natural lifelong process ending in death. Many older people are living in poverty. Older people are generally considered dependent on others as they grow older. The purpose of this article is to explore the... Aging is a natural lifelong process ending in death. Many older people are living in poverty. Older people are generally considered dependent on others as they grow older. The purpose of this article is to explore the entrepreneurship activities of Nepalese older adults. Data for this study were collected from the project Help Age International (HAI) implemented in Nepal. Qualitative data observations and interviews were used to collect data. The findings of this study show the formation of the Older People’s Association (OPA) has supported many older people to participate outside the home in various social activities. Moreover, regular deposits through OPAs offer little help. OPAs support older people in their need of financial support to implement minor entrepreneurship. Older people who received support were pleased and were actively involved in their activities and also regularly deposited money in them. Subsequently, older people’s participation in social activities has increased and also helped to lower elderly abuse, loneliness, and depression. Local governments should promote such activities which will help with healthy aging. 展开更多
关键词 aging in Nepal Active aging Older People’s Association Older People Healthy aging
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Ag-Cd和Ag-Sn-In合金等温内氧化过程研究
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作者 杨文涛 缪仁梁 +2 位作者 万岱 陈潺 罗宝峰 《电工材料》 CAS 2024年第2期26-29,32,共5页
制备了8种不同成分的Ag-Cd和Ag-Sn-In合金,探究它们的等温内氧化过程,并表征了其氧化后不同区域的组织与硬度。结果表明:Ag-Cd和Ag-Sn-In合金的等温氧化曲线均呈现抛物线状。根据曲线总结出氧化厚度平方的对数与氧化时间对数的线性方程... 制备了8种不同成分的Ag-Cd和Ag-Sn-In合金,探究它们的等温内氧化过程,并表征了其氧化后不同区域的组织与硬度。结果表明:Ag-Cd和Ag-Sn-In合金的等温氧化曲线均呈现抛物线状。根据曲线总结出氧化厚度平方的对数与氧化时间对数的线性方程,并分析对比Ag-CdO和Ag-SnO_(2)-In2O_(3)触点的组织形貌及硬度。 展开更多
关键词 ag-CdO ag-SnO_(2)-In2O_(3) 内氧化 电接触材料
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Ag-GNSs/Sn-Ag-Cu复合钎料焊点的润湿性能及界面生长特征研究
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作者 高子旋 屈敏 +1 位作者 康博雅 崔岩 《热加工工艺》 北大核心 2024年第13期50-54,共5页
采用Ag涂覆石墨烯纳米片(Ag-GNSs)作为增强体,制备Sn-3.0Ag-0.5Cu-(Ag-GNSs)新型复合无铅钎料,然后在Cu基板上制备了钎料焊点,并进行了150℃不同时长的等温时效处理,研究了不同含量的Ag-GNSs对无铅钎料Sn-3.0Ag-0.5Cu的润湿性、Cu基板/... 采用Ag涂覆石墨烯纳米片(Ag-GNSs)作为增强体,制备Sn-3.0Ag-0.5Cu-(Ag-GNSs)新型复合无铅钎料,然后在Cu基板上制备了钎料焊点,并进行了150℃不同时长的等温时效处理,研究了不同含量的Ag-GNSs对无铅钎料Sn-3.0Ag-0.5Cu的润湿性、Cu基板/钎料界面金属间化合物(IMC)生长特性的影响。结果表明,适量的Ag-GNSs可以显著地改善钎料的润湿性,当Ag-GNSs含量达到0.05wt%时润湿性最佳,与Sn-3.0Ag-0.5Cu钎料相比润湿角降低了54.43%。随着等温时效时间的延长,IMC层厚度增大,其生长行为由扩散控制。Ag-GNSs的添加可以抑制IMC层的生长,当Ag-GNSs的含量为0.05wt%时扩散系数达到最小值2.356×10^(-18)m^(2)/s。在0~0.2wt%范围内,Ag-GNSs的最佳添加量为0.05wt%。 展开更多
关键词 ag涂覆石墨烯纳米片(ag-GNSs) Sn-3.0ag-0.5Cu钎料 润湿性 IMC层
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高银系Sn-Ag-Cu/Cu界面金属间化合物生长行为
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作者 张欣 秦俊虎 +2 位作者 龙登成 梁东成 严继康 《焊接》 2024年第8期38-46,共9页
【目的】为研究高银系(Ag质量分数大于3.0%)Sn-Ag-Cu在固相时效过程中的界面反应和生长动力学。【方法】高温条件下不同银含量对界面结构和界面生长的影响,为了确定焊点的长期可靠性,在150℃下进行了0 h,100 h,300 h,500 h的热加速老化... 【目的】为研究高银系(Ag质量分数大于3.0%)Sn-Ag-Cu在固相时效过程中的界面反应和生长动力学。【方法】高温条件下不同银含量对界面结构和界面生长的影响,为了确定焊点的长期可靠性,在150℃下进行了0 h,100 h,300 h,500 h的热加速老化试验。用SEM与EDS进行了IMC表面形貌、厚度和元素组成。【结果】研究结果表明,随着银含量的增加,Cu_(6)Sn_(5)的生长受到不同程度抑制。在等温时效过程中,金属间化合物(IMC,Cu_(6)Sn_(5)+Cu_(3)Sn)的生长动力学是一个扩散控制过程,Cu_(6)Sn_(5)逐渐生长为Cu_(3)Sn;在后期的老化阶段,扇贝状的形状消失,表明生长机制发生了变化,变化为向垂直于界面方向的稳定生长;通过有限元技术,得出在服役过程中,热应力主要集中于Cu_(3)Sn与Cu基板交界处;随着时效时间的增加,焊点等效蠕变应变上升,可靠性逐渐降低;利用阿仑尼乌斯公式计算了金属间化合物IMC(Cu_(6)Sn_(5)+Cu_(3)Sn)在界面Sn-3.0Ag-0.7Cu/Cu,Sn-3.4Ag-0.7Cu/Cu,Sn-3.8Ag-0.7Cu/Cu的表观活化能分别为67.13 kJ/mol,70.50 kJ/mol,69.54 kJ/mol。【结论】根据试验与数值模拟计算相结合的研究手段,得到Sn-3.4Ag-0.7Cu款无铅焊料在高温服役过程中比其他焊料更能满足电子元件的要求。 展开更多
关键词 锡银铜焊料 界面生长 等温时效 IMC厚度
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电镀参数对电沉积Sn-Ag-Cu合金镀层的影响
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作者 文思倩 闫焉服 +1 位作者 周慧 程江洋 《稀有金属与硬质合金》 CAS CSCD 北大核心 2024年第1期63-68,80,共7页
采用自主研发的甲磺酸锡银铜电镀液在黄铜基体上制备了Sn-Ag-Cu合金镀层。通过扫描电子显微镜(SEM)及其自带的能谱仪(EDS)分析了电镀工艺参数对Sn-Ag-Cu合金镀层的成分、表面形貌以及镀层厚度产生的影响。结果表明,当电流密度为4 A/dm^... 采用自主研发的甲磺酸锡银铜电镀液在黄铜基体上制备了Sn-Ag-Cu合金镀层。通过扫描电子显微镜(SEM)及其自带的能谱仪(EDS)分析了电镀工艺参数对Sn-Ag-Cu合金镀层的成分、表面形貌以及镀层厚度产生的影响。结果表明,当电流密度为4 A/dm^(2)、温度为25℃及pH为5.5时,可获得结晶较细且致密,表面平整光亮且厚度均匀的Sn-Ag-Cu合金镀层。 展开更多
关键词 Sn-ag-Cu合金 电镀参数 甲磺酸锡银铜电镀液 表面形貌 镀层厚度 电流密度
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基于一锅法制备的Ag/AgCl/CeO_(2)复合纳米材料及其光催化有机物降解性能
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作者 陈垚 王瑾萱 +3 位作者 方嫣然 肖乐欣 杨纯 刘军 《包装学报》 2024年第4期64-71,共8页
采用一锅法制备Ag/CeO_(2)光催化剂,并通过原位氧化法进一步制备Ag/AgCl/CeO_(2)复合材料,使用XRD、SEM对Ag/AgCl/CeO_(2)复合纳米材料的结构、形貌进行表征,采用橙黄II、罗丹明6G、诱惑红等有机染料测试复合材料的光催化性能。结果表明... 采用一锅法制备Ag/CeO_(2)光催化剂,并通过原位氧化法进一步制备Ag/AgCl/CeO_(2)复合材料,使用XRD、SEM对Ag/AgCl/CeO_(2)复合纳米材料的结构、形貌进行表征,采用橙黄II、罗丹明6G、诱惑红等有机染料测试复合材料的光催化性能。结果表明:AgCl在Ag/AgCl中占比80%时,Ag/AgCl/CeO_(2)复合材料的光催化性能最佳,在模拟太阳光辐照6 min后能降解93%的橙黄II,且在4次循环8 min内能降解90%以上的橙黄II,在紫外-可见混合光照60 min后,能降解约90%的罗丹明6G和诱惑红。Ag/AgCl/CeO_(2)复合材料具有优异的光催化活性的主要原因是贵金属Ag的局域表面等离子共振效应以及金属/半导体异质结结构。 展开更多
关键词 一锅法 ag/CeO_(2) 贵金属光催化剂 ag/agCl
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Six Amino Acids among Natural Moisturizing Factors Responsible for Skin Hydration: Improvement and Anti-Aging of Skin by Galactomyces Ferment Filtrate-PiteraTM Containing Skin Moisturizer
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作者 Kukizo Miyamoto Yoko Munakata +4 位作者 Keisuke Fujii Wang Summer Ley Yang Suda Sudarsana Masutaka Furue 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第2期113-127,共15页
Background: Natural moisturizing factors (NMFs) are filaggrin-derived components in the cornified layer that are critical for maintaining healthy skin moisturization and barrier function. However, studies have reporte... Background: Natural moisturizing factors (NMFs) are filaggrin-derived components in the cornified layer that are critical for maintaining healthy skin moisturization and barrier function. However, studies have reported conflicting findings on the relationship between NMF levels and aging, while few studies have investigated this relationship clinically. To fill this research gap, we determined the levels of major NMF components such as free amino acids, pyrrolidone carboxylic acid, and urocanic acids, and individually verified their relationships with skin hydration, barrier function, age, and skin aging. Purpose: The objective of this study was to clinically investigate the relationship between NMF components levels and skin aging in facial skin. The main NMF components were obtained from facial skin and quantified. We then selected NMF components showing strong relationships to skin hydration, and analyzed the relationships of the levels of these selected NMF components with signs of skin aging, namely, texture, pores, wrinkles, and dullness (L-value). We also examined the efficacy of treatment with a skin care formula (SK-II Facial Treatment Essence, called SK-II FTE hereafter) including Galactomyces ferment filtrate (GFF, PiteraTM) on the selected NMF component levels associated with skin hydration and barrier function, and the signs of skin aging of texture, pores, wrinkles, and dullness (L-value). Method: We conducted two clinical trials in this research. In Study 1, we measured 23 NMF components using tape-stripped cornified layer to quantify them via an HPLC method in 196 Asian females aged 20 to 59 (mean S.D., 38.6 9.4). Facial visual aging parameters [texture, pores, wrinkles, and dullness (L-value)], as well as elasticity (R7), skin hydration, and TEWL, were quantified using facial skin imaging and skin physical property measurement devices. Study 2 was performed to evaluate whether the facial application of SK-II FTE affects the NMF levels and skin aging parameters in 63 Asian female volunteers aged 20 to 55 (38.4 9.03). During the course of Study 2, 0.6 mL of SK-II FTE was applied to the face twice daily in the morning and afternoon. Skin measurements were performed at the start of the day (baseline) and at week 8. Results: In Study 1, we examined the stratum corneum levels of 23 NMF components comparing to the skin hydration status in 196 female subjects. The subjects were divided into two groups using the median of each measured NMF component. Skin hydration values were compared between the two groups defined for each NMF component. The results showed that subjects with higher levels of six amino acids, alanine, arginine, asparagine, glutamine, glycine, and histidine, exhibited significantly higher skin hydration than those with lower amino acid levels. No significant differences in skin hydration values were found for the other 17 NMF components. We then analyzed whether the sum of these six amino acid NMF components (called 6-AA-NMFs, hereafter) is affected by aging. The 6-AA-NMF level peaked in the subjects aged 25-29, and then gradually and significantly decreased with age. Interestingly, the 6-AA-NMF level was significantly correlated with the skin hydration value, but not with TEWL. In addition, the 6-AA-NMF level demonstrated significant correlations with the signs of skin aging of texture, pores, wrinkles, and dullness (L-value). Then, in Study 2, we examined whether the daily application of SK-II FTE affects the 6-AA-NMF level and visual aging parameters in 63 females. SK-II FTE demonstrated significant increases of the levels of 6-AA-NMFs and each of its components associated with hydration and barrier function, and improvements of skin texture, pores, wrinkles, and dullness (L-value) during the 8 weeks of treatment of facial skin. Conclusion: These clinical studies with large numbers of subjects across a wide age range revealed that six amino acids as NMF components were highly correlated with facial skin hydration in the stratum corneum. The levels of these six NMF components were also found to decrease at ages after the 30 s and were significantly correlated with major signs of skin aging. Notably, these six NMF components (6-AA-NMFs) were increased by SK-II FTE treatment associated with improvements of skin hydration and signs of skin aging, namely, texture, pores, wrinkles, and dullness (L-value). These studies were limited by the lack of investigation of why some NMF components were not associated with skin hydration. More clinical trials examining various NMF components and their relationship with aging are anticipated. 展开更多
关键词 NMF Amino Acid Visual aging Parameter Hydration agING Texture Pore Wrinkle Dullness Galactomyces Ferment Filtrate PiteraTM SK-II Facial Treatment Essence
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Quantification of In Vivo Epidermal Keratinocyte Architecture Associated with the Signs of Skin Aging and the Skin Benefit Evaluation by Application of Galactomyces Ferment Filtrate (Pitera)-Containing Skin Care Product
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作者 Kukizo Miyamoto Yoko Munakata +4 位作者 Keisuke Fujii Chenlu Lei Ley Yang Suda Sudarsana Masutaka Furue 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第1期12-28,共17页
Background: Aged skin exhibits visual alterations such as wrinkles, rough texture, pore dilation, and dull skin tone, as well as physiological aging, namely, decreased hydration and increased transepidermal water loss... Background: Aged skin exhibits visual alterations such as wrinkles, rough texture, pore dilation, and dull skin tone, as well as physiological aging, namely, decreased hydration and increased transepidermal water loss (TEWL). Recent advances in coherence tomography have also revealed that skin aging affects in vivo epidermal keratinocyte architecture. However, the interconnectivity between spatial architectural aging and visual/physiological aging parameters remains largely unknown. Purpose: To elucidate whether the tomographic keratinocyte architectural aging is correlated with visual and physiological skin aging parameters and to quantitatively evaluate the improvements of the architectural, visual, and physiological aging parameters by the daily treatment of the skin care formula containing Galactomyces Ferment Filtrate (GFF, 8X Pitera<sup>TM</sup>). Method: We measured the in vivo keratinocyte cellular architecture with two-photon stereoscopic tomography obtaining by-layer epidermal section images in 78 Asian females of various ages. Visual aging parameters were analyzed using a portable image capture system. Hydration and TEWL were also assessed. The anti-aging effects of GFF-containing skin moisturizer (SK-II LXP Cream<sup>TM</sup>) were also examined in two studies after twice-daily application for 2 (N = 35) and 4 (N = 32) weeks. Results: As for the keratinocyte cellular architecture, skin aging was significantly associated with decreased cell density and increased cell uniformity. These architectural aging parameters were significantly correlated with visual and physiological aging parameters, namely, rough texture, wrinkles, pore dilation, dull skin tone, dehydration, and increased TEWL. The strong interconnectivity allowed us to develop formulae to estimate the keratinocyte architecture from visual aging parameters. Moreover, twice-daily application of SK-II significantly improved the keratinocyte architecture associated with multiple skin aging visual and physiological parameters. Conclusion: Skin aging is a process involving mutual interconnections among epidermal keratinocyte cellular architecture, visual, and physiological parameters. The GFF-containing moisturizer SK-II effectively improves spatial architecture of keratinocytes in epidermis and these evaluated skin aging parameters in a new trajectory over the course of treatment. . 展开更多
关键词 Facial Skin aging In Vivo Keratinocyte Cellular Architecture Visual aging Pa-rameter Dehydration INTERCONNECTIVITY New Trajectory Galactomyces Fer-ment Filtrate PiteraTM SK-II LXP CreamTM
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De-aging技术相关专利分析 被引量:1
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作者 李敏 《电视技术》 2023年第8期216-221,共6页
随着电视、电影特效等技术的快速发展,De-aging(即数字减龄、逆龄、去老化)技术得到了广泛的应用。对De-aging技术相关专利申请进行分析,从全球专利申请趋势、申请地域分布、申请人地域分布、主要申请人、申请人成分构成等方面进行详细... 随着电视、电影特效等技术的快速发展,De-aging(即数字减龄、逆龄、去老化)技术得到了广泛的应用。对De-aging技术相关专利申请进行分析,从全球专利申请趋势、申请地域分布、申请人地域分布、主要申请人、申请人成分构成等方面进行详细阐述,并基于技术分支和重要申请人对重点专利进行梳理,为后续De-aging专利的研发、专利申请或专利分析等提供依据。 展开更多
关键词 De-aging 逆龄 视觉效果
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预热处理温度对Ag-NH_(3)/SBA-15催化剂表面Ag物种形成及其催化性能的影响 被引量:1
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作者 李天佑 朱凌彬 +4 位作者 林凌 黄隆 陈冲冲 叶闰平 姚元根 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2023年第4期835-844,共10页
采用浸渍法将有序介孔分子筛SBA-15浸渍于银氨溶液中制备催化剂前驱体,然后在不同预热处理温度下制备了Ag-NH_(3)/SBA-15系列催化剂样品,并考察了其催化草酸二甲酯(DMO)加氢制备乙醇酸甲酯(MG)的反应性能。结果表明:控制适当的预热处理... 采用浸渍法将有序介孔分子筛SBA-15浸渍于银氨溶液中制备催化剂前驱体,然后在不同预热处理温度下制备了Ag-NH_(3)/SBA-15系列催化剂样品,并考察了其催化草酸二甲酯(DMO)加氢制备乙醇酸甲酯(MG)的反应性能。结果表明:控制适当的预热处理温度(如623 K)有利于生成更多能与硅羟基形成Ag—O—Si键的Ag 2O颗粒,从而抑制Ag物种的团聚,提高表面Ag物种分散度,还有利于形成更多带部分正电荷的Ag^(δ+)活性位,使H_(2)分子更容易被活化,进而提高Ag-NH_(3)/SBA-15催化剂的活性;在温度为483 K、压力为2.0 MPa、H_(2)/DMO摩尔比为100、液时质量空速(MHSV)为1.4 h^(-1)的反应条件下,Ag-NH_(3)/SBA-15-623K催化剂作用下DMO的加氢转化率为97.9%、MG的选择性和收率分别为94.9%和92.9%。 展开更多
关键词 ag基催化剂 SBA-15 预热处理温度 ag物种 草酸二甲酯 乙醇酸甲酯
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柔性AZO/NiCr/Ag/NiCr/AZO透明导电玻璃结构对性能的影响
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作者 姚婷婷 王天齐 +3 位作者 王伟 汪冰洁 李刚 甘治平 《表面技术》 EI CAS CSCD 北大核心 2023年第12期449-455,共7页
目的室温制备柔性透明导电玻璃并提高其光电性能。方法采用直流磁控溅射法,以柔性玻璃为基底,在室温下沉积(Aluminum-doped ZnO,AZO)/NiCr/Ag/NiCr/AZO多层结构透明导电玻璃。通过探针轮廓仪测试、X射线衍射仪(X-ray diffraction,XRD)... 目的室温制备柔性透明导电玻璃并提高其光电性能。方法采用直流磁控溅射法,以柔性玻璃为基底,在室温下沉积(Aluminum-doped ZnO,AZO)/NiCr/Ag/NiCr/AZO多层结构透明导电玻璃。通过探针轮廓仪测试、X射线衍射仪(X-ray diffraction,XRD)测试、拉曼光谱仪测试、分光光度计测量、四探针测试和霍尔效应测试,分别获得了样品的各层薄膜厚度、X射线衍射图谱、拉曼光谱、透光率、方块电阻和电学性能。经过参数优化,选取Ag膜厚度为3~15 nm的样品,研究Ag膜厚度对玻璃样品的结构特征及光电性能的影响。结果样品光电性能与Ag层厚度密切相关,随着中间Ag层厚度的增加,样品在380~760 nm波长范围内的平均光透光率先增加后降低,吸收边依次发生了红移,样品的方块电阻则随着Ag层厚度的增加单调减小。Ag膜厚度为12 nm的样品综合光电性能最佳,其平均透光率为82.4%,载流子浓度为8.32×10^(21) cm^(‒3),载流子迁移率为8.21 cm^(2)/(V·s),电阻率为9.15×10^(‒5)Ω·cm,方块电阻为8.8Ω/sq,品质因子可达16.4×10^(–3)Ω^(–1)。结论说明可以通过透明导电薄膜结合金属薄膜在室温下获得柔性透明导电玻璃,并具有较好的透光性能和导电性。 展开更多
关键词 柔性 透明导电玻璃 AZO/NiCr/ag/NiCr/AZO ag厚度 透光率 品质因子
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有序Au/Ag纳米碗阵列的简易制备及其表面增强拉曼散射性能 被引量:1
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作者 饶艳英 汪炳贵 +4 位作者 李章良 陈学文 丘丽蓉 徐宏 黄建辉 《无机化学学报》 SCIE CAS CSCD 北大核心 2023年第4期753-764,共12页
通过湿法化学合成基于SiO_(2)胶体晶体的大面积有序Au/Ag纳米碗(Au/AgNB)阵列。首先,在玻璃基板上组装3D SiO_(2)胶体晶体作为模板。然后,以Au纳米颗粒(AuNP)为种子,通过原位生长法在SiO_(2)模板上沉积一层Au纳米壳(AuNS)。再通过HCHO还... 通过湿法化学合成基于SiO_(2)胶体晶体的大面积有序Au/Ag纳米碗(Au/AgNB)阵列。首先,在玻璃基板上组装3D SiO_(2)胶体晶体作为模板。然后,以Au纳米颗粒(AuNP)为种子,通过原位生长法在SiO_(2)模板上沉积一层Au纳米壳(AuNS)。再通过HCHO还原Ag^(+)成Ag0,进一步在AuNS表面沉积Ag纳米壳,形成Ag/Au双纳米壳(Ag/AuNS)阵列。最后通过丙烯酸酯改性双向取向聚丙烯(BOPP)膜方便地获得了单层有序反转Ag/AuNB阵列。这种有序Au/AgNB阵列具有更佳的表面增强拉曼散射(SERS)活性,其SERS分析增强因子(AEF)可达2.23×10^(7)。 展开更多
关键词 金纳米壳 金/银纳米壳 金/银纳米碗 有序阵列 表面增强拉曼散射
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纳米Ag改性方式对锂氟化碳电池性能的影响
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作者 张红梅 甘潦 +2 位作者 王开琼 王庆杰 石斌 《电源技术》 CAS 北大核心 2023年第9期1164-1168,共5页
分别采用纳米Ag线和纳米Ag颗粒对氟化碳材料进行复合,以CF_(x)、CF_(x)@Ag1(复合纳米Ag线)、CF_(x)@Ag2(复合纳米Ag颗粒)为正极活性物质,制备5 Ah软包装锂氟化碳电池,研究纳米Ag线和纳米Ag颗粒复合对电池电化学性能的影响。使用X射线衍... 分别采用纳米Ag线和纳米Ag颗粒对氟化碳材料进行复合,以CF_(x)、CF_(x)@Ag1(复合纳米Ag线)、CF_(x)@Ag2(复合纳米Ag颗粒)为正极活性物质,制备5 Ah软包装锂氟化碳电池,研究纳米Ag线和纳米Ag颗粒复合对电池电化学性能的影响。使用X射线衍射(XRD)、扫描电子显微镜(SEM)、能量散射光谱(EDS)对材料的形貌结构进行表征分析并利用四探针测定其电导率,采用恒流放电测试及交流阻抗对电池的电化学性能进行分析,并测定电池恒流放电下的温度变化。结果表明,纳米Ag线和纳米Ag颗粒复合均可以提高CF_(x)材料的电导率,以改性材料为活性物质制备的电池具有更好的电化学性能和热稳定性,其中CF_(x)@Ag1的改性效果好于CF_(x)@Ag2。 展开更多
关键词 CF_(x) 纳米ag线 纳米ag颗粒 锂氟化碳电池 热稳定性
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Pre-S1Ag、Pre-S2Ag及HBV-LP在乙肝病毒检测中的性能 被引量:1
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作者 王庆果 石文斐 乔楠 《滨州医学院学报》 2023年第3期193-196,共4页
目的对三种HBV表面蛋白(Pre-S1 Ag、Pre-S2 Ag和HBV-LP)在HBV检测中的性能进行比较。方法通过对乙肝患者(包括HBsAg携带者和HBV DNA阳性患者)及健康人群Pre-S1 Ag、Pre-S2 Ag和HBV-LP的检测,对比分析其灵敏度、特异性和检出限。结果在进... 目的对三种HBV表面蛋白(Pre-S1 Ag、Pre-S2 Ag和HBV-LP)在HBV检测中的性能进行比较。方法通过对乙肝患者(包括HBsAg携带者和HBV DNA阳性患者)及健康人群Pre-S1 Ag、Pre-S2 Ag和HBV-LP的检测,对比分析其灵敏度、特异性和检出限。结果在进行HBV筛查时,三种表面蛋白特异性保持在99%~100%,反观Pre-S2 Ag和HBV-LP在检测HBsAg携带者、HBV-DNA阳性患者时,其敏感性表现要比Pre-S1 Ag更高(P<0.001)。三种表面蛋白吸光度与HBV-DNA水平呈正相关(P<0.001),Pre-S2 Ag和HBV-LP在HBV对应的检出限是2~3 Log10IU/mL,反观Pre-S1 Ag对HBV的检出限高于5 Log10IU/mL。结论通过Pre-S2 Ag、HBV-LP、Pre-S1 Ag对比来看,前面两者的敏感性较高,检出限较低,故可以用于HBV筛查、识别病毒的血清标志物。 展开更多
关键词 乙肝病毒 Pre-S1 ag Pre-S2 ag HBV-LP
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基于AGEs/RAGE/NF-κB通路探讨补肝散改善D-半乳糖致衰大鼠学习记忆障碍机制研究 被引量:1
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作者 李伟 王硕 +2 位作者 王杰鹏 方芳 方朝义 《Digital Chinese Medicine》 CAS CSCD 2023年第3期317-327,共11页
目的探讨复方补肝散(BGSD)干预D-半乳糖致衰大鼠学习记忆能力的潜在作用机制。方法40只大鼠被随机分为对照组、模型组、BGSD[14.06 g/(kg·d)]组和吡拉西坦[0.4 g/(kg·d)]组,每组10只。腹腔注射D-半乳糖[400 mg/(kg·d)]... 目的探讨复方补肝散(BGSD)干预D-半乳糖致衰大鼠学习记忆能力的潜在作用机制。方法40只大鼠被随机分为对照组、模型组、BGSD[14.06 g/(kg·d)]组和吡拉西坦[0.4 g/(kg·d)]组,每组10只。腹腔注射D-半乳糖[400 mg/(kg·d)]建立衰老大鼠模型。每周记录大鼠体质量、摄水量、摄食量和抓力;八臂迷宫和跳台实验评估大鼠学习记忆能力;称取肝脏、胸腺、脾脏和脑组织重量以计算相应脏器指数;检测血清丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性;苏木精-伊红(HE)染色观察海马病理学改变;酶联免疫吸附法(ELISA)检测海马肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6及IL-1β水平;实时荧光定量PCR(RT-qPCR)检测海马晚期糖基化终末产物受体(RAGE)、核因子-κB(NF-κB)、TNF-α、IL-6和IL-1βmRNA表达;蛋白免疫印迹法(WB)检测海马晚期糖基化终末产物(AGEs)、RAGE和NF-κB蛋白表达。结果补肝散可显著增加D-半乳糖致衰大鼠的摄食量、摄水量、体质量、抓力及脏器指数(P<0.05),减少八臂迷宫中工作记忆错误(WME)、参考记忆错误(RME)以及总记忆错误次数(TE)(P<0.05),降低跳台实验中错误次数并延长跳台潜伏期(P<0.05)。此外,补肝散可减少海马神经元损伤,提高血清SOD活性,降低MDA含量及下调促炎因子TNF-α、IL-6和IL-1β水平(P<0.05)。进一步研究结果显示,补肝散可显著降低海马AGEs、RAGE和NF-κB表达(P<0.05)。结论补肝散可通过抑制AGEs/RAGE/NF-κB信号通路调节D-半乳糖致衰大鼠神经炎症损伤从而改善学习记忆能力。 展开更多
关键词 补肝散 肝气虚 衰老 学习记忆 神经炎症 agEs/RagE/NF-κB信号通路
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Aging Trend and Situation in Nepal
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作者 Hom Nath Chalise 《Advances in Aging Research》 CAS 2023年第3期39-48,共10页
Aging is a natural lifelong process until death. The proportions of the older population are increasing rapidly in Nepal too. There are 2.97 million older people in Nepal as of the 2021 census which is a 38.2% increas... Aging is a natural lifelong process until death. The proportions of the older population are increasing rapidly in Nepal too. There are 2.97 million older people in Nepal as of the 2021 census which is a 38.2% increase compared to the previous census of 2011. The proportion of the older population reached 10.21% of the total population of Nepal. During this decade, Nepal’s average population growth rate is 0.92% and the older population growth rate is 3.29% per year. On the other hand, Nepal’s total fertility is below replacement level, infant mortality is around 23 per thousand live births and average life expectancy is now around 71 years. The median age of Nepal is 25 years and the index of aging increased rapidly from 23.3 in 2011 to 36.7 in the 2021 census of Nepal. These indicators show aging is taking place rapidly and the caregiving burden may increase rapidly in the coming days due to the tendency of migration of the young population to other countries. In this context, the Nepal government needs to focus on how to manage the population and provide quality services and social security for the growing older people of Nepal. 展开更多
关键词 aging in Nepal Older People of Nepal The Index of aging Nepal
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热处理工艺对微量Mn、Zr作用下的高纯Al-Cu-Mg-Ag合金性能的影响 被引量:6
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作者 朱宝宏 熊柏青 +1 位作者 张永安 熊益民 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2010年第1期144-148,共5页
研究了固溶处理和时效处理对微量Mn、Zr作用下的高纯Al-Cu-Mg-Ag合金性能的影响,结果表明:合金在520~525℃时,可以得到较好的力学性能,固溶时间对性能的影响不大。合金在160℃下时效12h可以达到峰时效,而在180℃下达到峰时效的时间仅需... 研究了固溶处理和时效处理对微量Mn、Zr作用下的高纯Al-Cu-Mg-Ag合金性能的影响,结果表明:合金在520~525℃时,可以得到较好的力学性能,固溶时间对性能的影响不大。合金在160℃下时效12h可以达到峰时效,而在180℃下达到峰时效的时间仅需要4h。向Al-Cu-Mg-Ag中添加微量Mn、Zr元素可以大幅度的提高合金的延伸率,但Mn元素的添加却降低合金的抗拉强度,而Zr元素则大幅度的提高了合金的抗拉强度。在合金的耐热性能方面,微量Mn、Zr元素的添加均显著提高Al-Cu-Mg-Ag合金的热稳定性。 展开更多
关键词 AL-CU-MG-ag 峰时效 固溶处理 时效处理
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