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The efficacy of a novel tomato extracts formulation on skin aging and pigmentation:A randomized,double-blind,parallel-controlled trial
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作者 Silu Zhang Shan Lu +2 位作者 Yun Wang Jiayi Ni Guoxun Xiao 《Journal of dermatologic science and cosmetic technology》 2024年第1期13-20,共8页
Background:Oxidative stress is a significant factor in skin aging and pigmentation,which can be precipitated by various circumstances.Antioxidants and tyrosinase inhibitors,such as carotenoids,yeast extract(glutathion... Background:Oxidative stress is a significant factor in skin aging and pigmentation,which can be precipitated by various circumstances.Antioxidants and tyrosinase inhibitors,such as carotenoids,yeast extract(glutathione),sodium hyaluronate,astaxanthin,and niacin,can individually protect the skin against aging through distinct mechanisms.These mechanisms potentially enhance the skin barrier and improve signs of aging and pigmentation.However,the synergistic effects of these compounds,as found in a golden tomato extract formulation,have been scarcely explored.Objective:To evaluate the effects of an orally administered formulation on the skin aging and pigmentation.Material and Methods:In this study,a randomized,double-blind,parallel-controlled trial was conducted,utilizing the WONDERLAB?Tomato Niacinamide beverage.Out of all participants,62 volunteers completed the experiment and were included in the statistical analysis.Results:The results indicated that after eight weeks of consuming the research product,there were no significant changes in the skin indicators within the placebo group.In contrast,the treatment group receiving the sample formulation exhibited a 35.63%increase in stratum corneum hydration and a 29.39%reduction in transepidermal water loss(TEWL),suggesting enhanced skin hydration.Visual assessments revealed improvements in skin color and gloss index by 15.03%and 11.41%,respectively,in the treatment group.Furthermore,the skin gloss and individual typology angle(ITA)value increased by 18.59%and 6.36%,respectively,leading to a lighter skin tone.Significant enhancements were also observed in skin pigmentation,color uniformity,and redness.After eight weeks of intervention with the sample,blood levels of superoxide dismutase(SOD)and glutathione peroxidase(GPx)increased,while malondialdehyde(MDA)levels decreased.Conclusion:These findings confirm that continuous intake of the tomato extract formulation over eight weeks effectively improved the volunteers'skin whitening and hydration,and visibly brightened skin tone through an antioxidant mechanism. 展开更多
关键词 Skin whitening Skin aging Antioxidant Gold tomato extracts Combination effect
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Precipitation orientation effect of 2124 aluminum alloy in creep aging 被引量:4
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作者 胥福顺 张劲 +1 位作者 邓运来 张新明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2067-2071,共5页
The precipitation behaviors of 2124 aluminum alloy under the conditions of artificial aging (AA), creep aging (CA) and creep aging with pre-deformation (PCA) were investigated by means of mechanical property and... The precipitation behaviors of 2124 aluminum alloy under the conditions of artificial aging (AA), creep aging (CA) and creep aging with pre-deformation (PCA) were investigated by means of mechanical property and microstructure. The results show that the mechanical properties of CA treated sample decrease significantly compared with AA treated sample. The yield strength of the CA treated sample falls by 14%, the tensile strength falls by 6.2%, and the elongation falls by 21%. Nevertheless, the mechanical properties of PCA sample are improved obviously, close to the AA treated sample. Moreover, the generation and control mechanisms of the precipitation orientation effect in 2124 aluminum alloy were studied. It is deduced that the key mechanism lies in the effect of dislocation. 展开更多
关键词 2124 aluminum alloy creep aging orientation effect DISLOCATION
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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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5%Ag掺杂对MNO_(2)纳米棒和海胆微球形貌及其甲苯氧化性能的影响
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作者 鲁美娟 方汉孙 +4 位作者 黄华军 李丹萍 吴玮玲 屈小路 喻成龙 《环境工程技术学报》 CAS CSCD 北大核心 2024年第4期1239-1246,共8页
采用水热法制备了MNO_(2)纳米棒和海胆微球,并原位掺杂5%Ag制备了Mn-Ag复合氧化物,利用SEM、XRD、BET、Raman等表征技术对其结构进行表征,并考察不同催化剂对甲苯的去除性能。结果表明:(NH_(4))_(2)S_(2)O_(8)的掺入量会对MNO_(2)的形... 采用水热法制备了MNO_(2)纳米棒和海胆微球,并原位掺杂5%Ag制备了Mn-Ag复合氧化物,利用SEM、XRD、BET、Raman等表征技术对其结构进行表征,并考察不同催化剂对甲苯的去除性能。结果表明:(NH_(4))_(2)S_(2)O_(8)的掺入量会对MNO_(2)的形貌产生影响,当其掺入量为2.28 g时,形成MNO_(2)纳米棒,当其掺入量为6.84 g时,形成MNO_(2)海胆微球;MNO_(2)纳米棒掺杂5%的Ag后,形貌未发生变化,但当MNO_(2)海胆微球掺杂5%Ag时,表面的纳米线较MNO_(2)海胆微球有所增长,且出现了缠绕现象,形成了空心鸟巢状结构;5%Ag掺杂后,对MNO_(2)纳米棒和MNO_(2)海胆微球的晶型未产生影响,均为α-MNO_(2),但5%Ag-MNO_(2)纳米棒出现了Mn2O_(3)的衍射峰;MNO_(2)海胆微球较MNO_(2)纳米棒的比表面积、孔径和孔容均增大,且Ag的掺杂进一步提高了MNO_(2)海胆微球的比表面积、孔径和孔容;MNO_(2)海胆微球比MNO_(2)纳米棒具有更好的甲苯去除性能,且5%Ag掺杂后,MNO_(2)海胆微球对甲苯的去除性能达到最好。 展开更多
关键词 MNO_(2)纳米棒 MNO_(2)海胆微球 ag掺杂 形貌影响 甲苯去除
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Hardening effect and precipitation evolution of an isothermal aged Mg-Sm based alloy 被引量:2
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作者 Kai Guan Chuang Li +7 位作者 Zhizheng Yang Yongsen Yu Qiang Yang Wenwen Zhang Zhiping Guan Cheng Wang Min Zha Huiyuan Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第12期4619-4627,共9页
The age-hardening behavior and precipitation evolution of an isothermal aged Mg-5Sm-0.6Zn-0.5Zr(wt.%) alloy have been systematically investigated by means of transmission electron microscopy(TEM) and atomic-resolution... The age-hardening behavior and precipitation evolution of an isothermal aged Mg-5Sm-0.6Zn-0.5Zr(wt.%) alloy have been systematically investigated by means of transmission electron microscopy(TEM) and atomic-resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM). The Vickers hardness of the present alloy increases first and then decreases with ageing time. The sample aged at 200 ℃ for 10 h exhibits a peak-hardness of 90.5 HV. In addition to the dominant β_(0)’ precipitate(orthorhombic,a = 0.642 nm, b = 3.336 nm and c = 0.521 nm) formed on {11-20}α planes, a certain number of γ’’ precipitate(hexagonal, a = 0.556 nm and c = 0.431 nm) formed on basal planes are also observed in the peak-aged alloy. Significantly, the basal γ’’ precipitate is more thermostable than prismatic β_(0)’ precipitate in the present alloy. β_(0)’ precipitates gradually coarsened and were even likely to transform into β_(1) phase(face centered cubic, a = 0.73 nm) with the increase of ageing time, which accordingly led to a gradual decrease in number density of precipitates and finally resulted in the decreased hardness and mechanical property in the over-aged alloys. 展开更多
关键词 Magnesium alloys ageing treatment Microstructure characterization age-hardening effect PRECIPITATES
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Seminal characteristics and sexual behavior in men of different age groups: is there an aging effect? 被引量:10
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作者 Panayiotis M. Zavos Khalied Kaskar +1 位作者 Juan R. Correa Suresh C. Sikka 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第3期337-341,共5页
Aim: To assess the seminal characteristics as well as the sexual behavior of men of various age groups to establish the presence of an aging effect on those characteristics. Methods: Semen samples were collected fro... Aim: To assess the seminal characteristics as well as the sexual behavior of men of various age groups to establish the presence of an aging effect on those characteristics. Methods: Semen samples were collected from men (n = 792) undergoing in vitro fertilization or intrauterine insemination in cases of female factor infertility only. Samples were collected using a seminal collection device at intercourse and evaluated manually according to World Health Organization (WHO) standards. Men were divided into four groups according to their ages: (i) 20-30, (ii) 31-40, (iii) 41-50 and (iv) 51-60 years, and their seminal characteristics and responses to a sexual behavior questionnaire were compared. Results: The data showed statistically significant differences in the seminal characteristics tested, most notably in the sperm concentration, motility, grade of motility, hypo-osmotic swelling and normal sperm morphology. Furthermore, the decline in normal sperm morphology with age was more pronounced when using strict criteria rather than WHO standards. There were also differences in total sperm count, total motile sperm and total functional sperm fraction (assessed by both WHO and strict criteria). Significant differences were also observed in the sexual behavior patterns in older men in terms of the number of years they have been trying to conceive, sexual frequency and sexual satisfaction. Conclusion: The data clearly illustrate an aging effect on semen characteristics and sexual behavior in men as they age. It is suggested that the aging effect be taken into consideration when proposing normal standard values for semen characteristics in routine semen analysis as outlined by WHO standards. 展开更多
关键词 seminal parameters MALE aging effect FERTILITY sexual behavior semen quality male factor infertility
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Aging effect on the mobility and bioavailability of copper in soil 被引量:3
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作者 LU Anxiang ZHANG Shuzhen +2 位作者 QIN Xiangyang WU Wenyong LIU Honglu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第2期173-178,共6页
Aging effect on the mobility and bioavallability of copper (Cu) was investigated using a spiked soil with different incubation periods from 3 to 56 d. Wheat was planted and earthworms were cultured separately in the... Aging effect on the mobility and bioavallability of copper (Cu) was investigated using a spiked soil with different incubation periods from 3 to 56 d. Wheat was planted and earthworms were cultured separately in the incubated soils. The mobility of Cu in soil was evaluated by a chemical fractionation scheme and the toxicity and bioavailability were assessed by measuring the biomass and Cu concentration in tissues. Results showed that aging had a significant effect on Cu fraction distribution, of which Cu tended to incorporate from the exchangeable into more stable fractions such as the reducible and oxidisable fractions. However, aging had little effect on Cu bioavailability to wheat and earthworm. Comparing the soil being incubated for 3 d and 56 d, Cu concentration in wheat roots decreased from 14.5 to 12.8 mg/kg, and no significant changes in Cu concentration were observed in both wheat shoots and earthworms. The Cu concentration was around 2.0 and 50 mg/kg for wheat shoots and earthworms, respectively, irrespective of soil incubation time. The CaC12-extractable Cu had a linear relationship with Cu concentration in wheat roots (R2 = 0.65, P 〈 0.05), but no linear relationship can be found for wheat shoots and earthworms. Biological control may be more crucial for Cu accumulation in organism than the changes in soil Cu fraction caused by aging. 展开更多
关键词 aging effect COPPER MOBILITY BIOAVAILABILITY
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Research on the threshold effect of population aging on the industrial structure upgrading in China 被引量:3
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作者 Chengkun Liu Shuyu Li Xindong Zhao 《Chinese Journal of Population,Resources and Environment》 2019年第1期87-100,共14页
This paper constructs coefficients of the integral and the internal structure upgrading in the secondary and tertiary industries, selects per capita real gross domestic product as a threshold variable and build panel ... This paper constructs coefficients of the integral and the internal structure upgrading in the secondary and tertiary industries, selects per capita real gross domestic product as a threshold variable and build panel threshold model according to inter-provincial panel data of China from 1998 to 2016. Results indicated that population aging has a double threshold effect on the integral industrial structure upgrading, whose influence increases first and then decreases, significantly promoting the upgrading process. As for internal structure, population aging has no significant threshold effect on the upgrading in the secondary industry, but exerts a single negative threshold effect in the tertiary industry. When economic development is under the threshold, its negative impact is greater. Further analysis also suggests that regional differences exist significantly in the threshold effect of population aging on the industrial structure upgrading. 展开更多
关键词 POPULATION aging INDUSTRIAL structure UPGRADING THRESHOLD effect
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Mechanistic investigation on Ag-Cu_(2)O in electrocatalytic CO_(2) to CH_(4) by in situ/operando spectroscopic and theoretical analysis 被引量:1
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作者 Min Sun Luxiao Zhang +10 位作者 Fuli Tian Jiaxin Li Yanqiu Lei Heng Zhang Lifeng Han Zhihua Guo Yonghui Gao Fenrong Liu Yan Wang Luhui Wang Shanghong Zeng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期521-531,I0012,共12页
Silver-copper electrocatalysts have demonstrated effectively catalytic performance in electroreduction CO_(2) toward CH_(4),yet a revealing insight into the reaction pathway and mechanism has remained elusive.Herein,w... Silver-copper electrocatalysts have demonstrated effectively catalytic performance in electroreduction CO_(2) toward CH_(4),yet a revealing insight into the reaction pathway and mechanism has remained elusive.Herein,we construct chemically bonded Ag-Cu_(2)O boundaries,in which the complete reduction of Cu_(2)O to Cu has been strongly impeded owing to the presence of surface Ag shell.The interfacial confinement effect helps to maintain Cu^(+)sites at the Ag-Cu_(2)O boundaries.Using in situ/operando spectroscopy and theoretical simulations,it is revealed that CO_(2) is enriched at the Ag-Cu_(2)O boundaries due to the enhanced physisorption and chemisorption to CO_(2),activating CO_(2) to form the stable intermediate^(*)CO.The boundaries between Ag shell and the Cu_(2)O mediate local^(*)CO coverage and promote^(*)CHO intermediate formation,consequently facilitating CO_(2)-to-CH_(4) conversion.This work not only reveals the structure-activity relationships but also offers insights into the reaction mechanism on Ag-Cu catalysts for efficient electrocatalytic CO_(2) reduction. 展开更多
关键词 ag shell Interfacial confinement effect Cu~+ Local*CO coverage CO_(2)reduction
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Effects of aging on the microstructure of a Cu-Al-Ni-Mn shape memory alloy 被引量:1
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作者 U.Sari T.Kirindi +1 位作者 F.Ozcan M.Dikici 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2011年第4期430-436,共7页
The influence of aging on the microstructure and mechanical properties of Cu-11.6wt%Al-3.9wt%Ni-2.5wt%Mn shape memory alloy(SMA) was studied by means of scanning electron microscopy(SEM),transmission electron micr... The influence of aging on the microstructure and mechanical properties of Cu-11.6wt%Al-3.9wt%Ni-2.5wt%Mn shape memory alloy(SMA) was studied by means of scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffractometer,and differential scanning calorimeter(DSC).Experimental results show that bainite,γ2,and α phase precipitates occur with the aging effect in the alloy.After aging at 300°C,the bainitic precipitates appear at the early stages of aging,while the precipitates of γ2 phase are observed for a longer aging time.When the aging temperature increases,the bainite gradually evolves into γ2 phase and equilibrium α phase(bcc) precipitates from the remaining parent phase.Thus,the bainite,γ2,and α phases appear,while the martensite phase disappears progressively in the alloy.The bainitic precipitates decrease the reverse transformation temperature while the γ2 phase precipitates increase these temperatures with a decrease of solute content in the retained parent phase.On the other hand,these precipitations cause an increasing in hardness of the alloy. 展开更多
关键词 copper alloys shape memory effect martensitic transformations aging PRECIPITATES
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Effects of aging treatment on the microstructure and superelasticity of columnar-grained Cu71Al18Mn11 shape memory alloy 被引量:3
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作者 Ji-li Liu Hai-you Huang Jian-xin Xie 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第10期1157-1166,共10页
The effect of aging treatment on the superelasticity and martensitic transformation critical stress in columnar-grained Cu_(71)Al_(18)Mn_(11) shape memory alloy(SMA) at the temperature ranging from 250°C ... The effect of aging treatment on the superelasticity and martensitic transformation critical stress in columnar-grained Cu_(71)Al_(18)Mn_(11) shape memory alloy(SMA) at the temperature ranging from 250°C to 400°C was investigated. The microstructure evolution during the aging treatment was characterized by optical microscopy, scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The results show that the plate-like bainite precipitates distribute homogeneously within austenitic grains and at grain boundaries. The volume fraction of bainite increases with the increase in aging temperature and aging time, which substantially improves the martensitic transformation critical stress of the alloy, whereas the bainite only slightly affects the superelasticity. This behavior is attributed to a coherent relationship between the bainite and the austenite, as well as to the bainite and the martensite exhibiting the same crystal structure. The variations of the martensitic transformation critical stress and the superelasticity of columnar-grained Cu_(71)Al_(18)Mn_(11) SMA with aging-temperature and aging time are described by the Austin-Rickett equation, where the activation energy of bainite precipitation is 77.2 kJ ·mol1. Finally, a columnar-grained Cu_(71)Al_(18)Mn_(11) SMA with both excellent superelasticity(5%-9%) and high martensitic transformation critical stress(443-677 MPa) is obtained through the application of the appropriate aging treatments. 展开更多
关键词 copper aluminum manganese alloys shape memory effect columnar grains aging bainite superelasticity
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Martensite Aging Effect and Thermal Cyclic Characteristics in Ti-Pd and Ti-Pd-Ni High Temperature Shape Memory Alloys 被引量:2
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作者 Wei Cai School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 15000k, China Kazuhiro Otsuka Institute of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan E-mail: weicai@hope.hit.edu.cn 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第3期359-362,共4页
The effect of thermal cycling and aging in martensitic state in Ti-Pd-Ni alloys were investigated by DSC and TEM observations. It is shown that the thermal cycling causes the decreases in M, and Af temperatures in Ti5... The effect of thermal cycling and aging in martensitic state in Ti-Pd-Ni alloys were investigated by DSC and TEM observations. It is shown that the thermal cycling causes the decreases in M, and Af temperatures in Ti50Pd50-xNix (x=10, 20, 30) alloys, but no obvious thermal cycling effect was observed in Ti50Pd50Pd40Ni10 alloys and the aging effect shows a curious feature, i.e., the Af temperature does not saturate even after relatively long time aging, which is considered to be due to the occurrence of recovery recrystallization during aging. 展开更多
关键词 Ti Martensite aging effect and Thermal Cyclic Characteristics in Ti-Pd and Ti-Pd-Ni High Temperature Shape Memory Alloys PD Ni
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Vertical and horizontal displacements of a reservoir slope due to slope aging effect,rainfall,and reservoir water 被引量:1
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作者 Dongzhen Jia Ye Zhou +3 位作者 Xiufeng He Nan Xu Zhixiang Yang Minfeng Song 《Geodesy and Geodynamics》 CSCD 2021年第4期266-278,共13页
Landslides are common hazards in reservoir areas and significantly affect dam operation and human lives.For the prevention and management of landslides,accurate assessment of the factors influencing their generation i... Landslides are common hazards in reservoir areas and significantly affect dam operation and human lives.For the prevention and management of landslides,accurate assessment of the factors influencing their generation is essential.This study evaluated the key external factors influencing horizontal and vertical displacements of Luobogang Reservoir Slope in Hanyuan County,China.Displacements had been monitored by a surface-displacement-monitoring system consisting of 118 GPS stations during 2012-2015.To identify the external driving factors,their influence zones,and slope responses,we analyzed 32 months of displacement measurements and other multi-source datasets using the empirical orthogonal function.Overall,the results show that slope aging effect,rainfall,and reservoir water levels are three main driving factors.For horizontal displacement,aging effect is the most critical factor and predominantly affects the edges of landslides,the gob cave,and the public building zones.The secondary factor is the reservoir water level,which mainly acts on the boundary between the slope and reservoir water surface.The closer the slope zone is to the reservoir water,the more significant the impact is.Regarding vertical displacement,the most important factor is rainfall.The vertical displacement caused by rainfall accounts for 56.76% of the total vertical displacements.However,rainfall induces elastic displacements that generally cause less damage to the slope.The secondary factor is aging effect,and the vertical displacement caused by aging effect accounts for 9.42%.However,seven individual zones are highly affected by slope aging effect,which is consistent with the distribution of public buildings. 展开更多
关键词 Reservoir slope Horizontal and vertical displacements Influencing factors aging effect Reservoir water level
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Ag掺杂ZnO微纳米结构的制备及发光特性
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作者 邓田田 田雪 孙元平 《烟台大学学报(自然科学与工程版)》 CAS 2024年第2期207-212,共6页
采用微波水热法在80~140℃的生长温度下合成了一系列银(Ag)掺杂的氧化锌(ZnO)样品,掺杂液中Ag^(+)质量分数分别为0、0.2%、0.5%和1%,并采用X射线衍射(XRD)、扫描电镜(SEM)、室温荧光(PL)等方法详细研究了Ag的掺杂对ZnO的结构、形貌和光... 采用微波水热法在80~140℃的生长温度下合成了一系列银(Ag)掺杂的氧化锌(ZnO)样品,掺杂液中Ag^(+)质量分数分别为0、0.2%、0.5%和1%,并采用X射线衍射(XRD)、扫描电镜(SEM)、室温荧光(PL)等方法详细研究了Ag的掺杂对ZnO的结构、形貌和光学性能的影响。XRD结果显示,在低温条件下,高浓度Ag掺杂的ZnO结晶质量最好,而在高温条件下,纯ZnO的结晶质量优于Ag掺杂样品;SEM结果表明,ZnO为空心纳米结构,纯ZnO样品随着温度的升高,样品的形貌由中空的棒状结构逐渐转化为多层的片状结构,而随着Ag掺杂浓度的增加,中空的六方柱状结构逐渐解体,样品颗粒减小,这一现象符合介孔形成的基本理论——柯肯达尔效应;PL光谱表明,随着Ag掺杂浓度的增大,ZnO的可见光发光强度呈现出先增强后减弱的趋势,能带的带隙则逐渐变窄。Ag的掺杂浓度和样品生长温度对于ZnO的结构、形貌和光学性能起了关键性作用。 展开更多
关键词 微波水热法 ZNO ag掺杂 柯肯达尔效应 光学性质
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WS_(2)@Ag复合材料光热降解RhB性能研究
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作者 储德亮 刘钟馨 王洁琼 《水处理技术》 CAS CSCD 北大核心 2024年第6期80-84,共5页
光热过程是太阳能利用中最有效的能量转换过程。在这项研究中,将制备的WS_(2)@Ag复合材料作为光热催化剂。结合过一硫酸盐(PMS)辅助催化去除有机染料RhB。通过UV-Vis、XRD、SEM、TEM等测试手段对该催化剂进行了表征。并在一个模拟太阳... 光热过程是太阳能利用中最有效的能量转换过程。在这项研究中,将制备的WS_(2)@Ag复合材料作为光热催化剂。结合过一硫酸盐(PMS)辅助催化去除有机染料RhB。通过UV-Vis、XRD、SEM、TEM等测试手段对该催化剂进行了表征。并在一个模拟太阳光照射下,以广泛使用的有机染料RhB的降解为例,从光热催化、光催化和热催化等方面综合评价了WS_(2)@Ag复合材料的光热降解性能。动力学分析表明,WS_(2)@Ag作为催化剂,光热组的降解效率分别是纯光组和纯热组的1.33和1.82倍,在50 min内降解率达到95%。系统地研究了光热催化条件下催化剂和PMS的用量及复合材料的循环稳定性,通过捕获实验测试结果表明:WS_(2)@Ag/PMS催化体系中存在SO_(4)^(·-)、·OH和^(1)O_(2)活性物种,协同降解RhB。最后提出了WS_(2)@Ag材料通过不同方式激活PMS产生高活性物种来氧化RhB的降解机理。 展开更多
关键词 光热催化 降解有机染料 WS_(2)@ag 表面等离子效应
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Aging Effect on Lanthanum Doped Ferroelectric Lead Titanate Ceramics
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作者 孙大志 金雪琴 +1 位作者 朱杰 朱玉丹 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期228-230,共3页
Ferroelectric devices are widely applied in many fields, such as energy conversion and communication. The aging effect in ferroelectric materials plays a central role in the reliability of the related equipments. But ... Ferroelectric devices are widely applied in many fields, such as energy conversion and communication. The aging effect in ferroelectric materials plays a central role in the reliability of the related equipments. But it is very difficult to understand the origin of aging effect in ferroelectrics because these materials possess different defects and exhibit various aging behavior. The reverse transition temperature in lead titanate doped with lanthanum increases during aging at ferroelectric phase was reported. It is well known that lattice defects, such as vacancies and solute atoms, are ubiquitous in crystalline solids. These point defects affect physical properties in ferroelectrics significantly. The abnormal increase of the reverse transition temperature was discussed in terms of diffusion of point defects during aging. Dielectric performance in the material after aging was measured and discussed as well. 展开更多
关键词 aging effect FERROELECTRIC reverse transformation temperature (Pb La)TiO3 rare earths
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AI’s Effects on Economic Growth in Aging Society: Induced Innovation and Labor Supplemental Substitution
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作者 Chen Qiulin Xu Duo Zhou Yi 《China Economist》 2019年第5期54-66,共13页
This paper employs industrial robot installations that represent the level of smart manufacturing as the proxy variable of artificial intelligence(AI). Based on crosscountry panel data and China's provincial panel... This paper employs industrial robot installations that represent the level of smart manufacturing as the proxy variable of artificial intelligence(AI). Based on crosscountry panel data and China's provincial panel data, we create a two-stage least square(2 SLS) regression model to examine the effect of an aging population on AI applications and AI's effect on economic growth. In this manner, we aim to test whether AI has a substitutive effect on labor against the backdrop of an aging society and the kind of such a substitutive effect. Our findings suggest that the labor shortage arising from an aging society will prompt an economy to adopt smart manufacturing more broadly, i.e. an aging society is a driver of AI development. Smart manufacturing has a positive effect on local GDP and helps shore up the slowing economy resulting from an aging society. AI is an important tool for coping with the challenges of an aging society. Current AI development is an "induced innovation," and its substitutive relationship with labor is a "supplemental substitution" rather than "crowding-out substitution." If these characteristics are properly maintained, AI will contribute more to China's economy against the backdrop of an aging society. 展开更多
关键词 aging SOCIETY artificial INTELLIGENCE smart manufacturing substitutive effect
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Atmospheric Pressure Plasma Treatment and Following Aging Effect of Chromium Surfaces
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作者 Vadym Prysiazhnyi 《Journal of Surface Engineered Materials and Advanced Technology》 2013年第2期138-145,共8页
The results of atmospheric pressure plasma treatments using diffuse coplanar surface barrier discharge (type of surface dielectric barrier discharge) on chromium surfaces are reported. A significant increase of surfac... The results of atmospheric pressure plasma treatments using diffuse coplanar surface barrier discharge (type of surface dielectric barrier discharge) on chromium surfaces are reported. A significant increase of surface wettability was observed after short plasma exposition. A quantitative value of surface wettability, i.e. the surface free energy, changed from 29 mJ/m2 to over 80 mJ/m2. In time, a hydrophobic recovery of the plasma treated surfaces was observed. Careful study by surface free energy measurements and x-ray photoelectron spectroscopy was performed to be able explaining the effects of plasma treatment. Studied samples were treated in air, oxygen and nitrogen plasma and aged in air and vacuum. Main reasons for increased wettability and aging effect are surface cleaning and transformations in chromium oxide. Additionally, generation of surface nitrate groups was found on the chromium surface as a result of plasma treatment in humid air. 展开更多
关键词 CHROMIUM Surface Plasma Treatment DCSBD aging effect ATMOSPHERIC Pressure PLASMAS
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Pseudotargeted metabolomics for exploring the changes of neurotransmitters profile in aging rat brain and the potential neuroprotective effect of alkaloids from Uncaria rhynchophylla
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作者 Shi-Wei Li Yi-Song Wu +4 位作者 Shi-Fei Wu Wen-Long Wei Ming-Yang Qiu Yun Li De-An Guo 《Traditional Medicine Research》 2022年第5期1-9,共9页
Background:Aging is an essential risk factor for most neurodegenerative diseases,including Alzheimer’s disease and Parkinson’s disease.However,changes in the levels of neurotransmitters that are associated with agin... Background:Aging is an essential risk factor for most neurodegenerative diseases,including Alzheimer’s disease and Parkinson’s disease.However,changes in the levels of neurotransmitters that are associated with aging are not well understood.Methods:Methods such as liquid-liquid extraction,protein precipitation,and solid-phase extraction,using 20 different extraction solvents,were evaluated to optimize the extraction of neurotransmitters.A pseudotargeted metabolomics approach was developed to detect neurotransmitters in brain tissues using ultra-high-performance liquid chromatography coupled with tandem triple quadrupole mass spectrometry.Alkaloids that crossed into the brain were used to evaluate the effect of glutamic acid-induced excitatory neurotoxicity in SH-SY5Y cells.Results:The overall extraction efficiency using protein precipitation was high.The changes in neurotransmitters’levels in the brain exhibited changes during the different growth cycles.The levels of seven neurotransmitters(aspartic acid,tyrosine,isoleucine,leucine,tryptophan,valine,andγ-aminobutyric acid)were significantly different.Meanwhile,alkaloids could reduce the excitatory neurotoxicity of glutamic acid-induced SH-SY5Y cells via suppression of oxidative stress.Conclusion:Significant differences were observed in neurotransmitter profiling between 1-and 8-month-old rats,and the discrepant neurotransmitters were associated with aging.Seven indole alkaloids from Uncaria rhynchophylla,which could cross the blood-brain barrier,were screened and used to explore their protective effects against aging.Uncaria rhynchophylla alkaloids exhibited a neuroprotective effect by inhibiting oxidative stress,indicating that the alkaloid could be a potential therapeutic candidate for neurological disorders caused by glutamic acid toxicity. 展开更多
关键词 NEUROTRANSMITTERS aging Uncaria rhynchophylla indole alkaloids neuroprotective effect pseudotargeted metabolomics
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Estrogen rapid effects:a window of opportunity for the aging brain?
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作者 Ivanny Marchant Jana Stojanova +1 位作者 Lilian Acevedo Pablo Olivero 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第8期1629-1632,共4页
Estrogen produces several beneficial effects in healthy neurological tissues and exhibits cardioprotective effects.Hormone therapy has been widely used to treat menopausal estrogen deficiency for more than 80 years.De... Estrogen produces several beneficial effects in healthy neurological tissues and exhibits cardioprotective effects.Hormone therapy has been widely used to treat menopausal estrogen deficiency for more than 80 years.Despite high initial expectations of cardioprotective effects,there has been substantial distrust following important randomized clinical trials,such as the Women’s Health Initiative.Subsequently,the timing of treatment in relation to the onset of menopause came under consideration and led to the proposal of the timing hypothesis,that early initial treatment is important,and benefits are lost as the timing since menopause becomes prolonged.Subsequent analyses of the Women’s Health Initiative data,together with more recent data from randomized and observational trials,consistently show reductions in coronary heart disease and mortality in younger menopausal women.Regarding cognitive function,the timing hypothesis is consistent with observations from basic and animal studies.There is some clinical evidence to support the benefits of hormonal therapy in this context,though skepticism remains due to the paucity of clinical trials of substantial length in younger menopausal women.It is likely that the effects of estrogens on cognitive performance are due to rapid mechanisms,including mechanisms that influence Ca2+homeostasis dynamics,provide protection in a hostile environment and reduce inflammatory signals from neural tissues.In the future,inflammatory profiles accounting for early signs of pathological inflammation might help identify the‘window of opportunity’to use estrogen therapy for successful cognitive protection. 展开更多
关键词 aging cardiovascular prevention cognitive function ESTROGEN hormone treatment INFLAMMaging rapid effects timing hypothesis TRPV1 window of opportunity
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