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Study on Correlation of Different Methods of Evaluating Degree of Skin Redness
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作者 Jian Yuanqing Ma Lin +3 位作者 Huang Bingting Li Jing Zhang Xiaojie Sun Lili 《China Detergent & Cosmetics》 CAS 2024年第3期50-55,共6页
In order to explore the correlation of 3 different methods of evaluating the degree of skin redness,45 healthy Chinese subjects aged 18~45 were recruited to attend a human efficacy evaluation test.An emulsion product ... In order to explore the correlation of 3 different methods of evaluating the degree of skin redness,45 healthy Chinese subjects aged 18~45 were recruited to attend a human efficacy evaluation test.An emulsion product which declares soothing and repair efficacy was used each time in the morning and evening for 4 weeks.Three methods,including visual assessment,image analysis and instrument measurement,were taken to test the related indices of skin redness degree respectively.The improvement of skin redness and the correlation of 3 methods were evaluated by comparing the changes of each index before and after using the product.The results show that the face redness degree score and the image analysis a*value significantly reduce at all time points after using the sample(P<0.05),while the instrument probe a*value significantly reduce at the time point after using for 2 weeks(P<0.05).The correlation coefficient of the face redness degree score and the instrument probe a*value is more than 0.33 and less than 0.67,and the significance level is less than 0.01.Therefore,the sample has soothing and repair efficacy for improving skin redness;and the methods of visual assessment and instrument measurement present moderate positive correlation. 展开更多
关键词 SKIN redness COSMETICS efficacy evaluation CORRELATION
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Dietary supplementation with turmeric polyherbal formulation decreases facial redness: a randomized double-blind controlled pilot study 被引量:1
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作者 Alexandra R.Vaughn Aunna Pourang +2 位作者 Ashley K.Clark Waqas Burney Raja K.Sivamani 《Journal of Integrative Medicine》 SCIE CAS CSCD 2019年第1期20-23,共4页
Background: Facial redness is multifactorial in nature and may be a sign of many different conditions,including rosacea, photo damage and flushing. Herbal medicines have been used for thousands of years to treat a var... Background: Facial redness is multifactorial in nature and may be a sign of many different conditions,including rosacea, photo damage and flushing. Herbal medicines have been used for thousands of years to treat a variety of dermatological conditions. Turmeric(Curcuma longa) and its constituents have been shown to mediate dilation and constriction of peripheral arterioles and have demonstrated anti-oxidant,anti-inflammatory and wound-healing properties.Objective: To investigate the effects of turmeric and turmeric-containing polyherbal combination tablets versus placebo on facial redness.Design, setting, participants, and interventions: This was a prospective, double-blind, randomized pilot study. Thirty-three healthy participants were recruited from the dermatology clinic at the University of California, Davis and nearby community from 2016 to 2017. Thirty participants were enrolled, and28 participants completed the study. The enrolled participants were randomized to receive one of three interventions(placebo, turmeric or polyherbal combination tablets) and were told to take the intervention tablets by mouth twice daily for 4 weeks. Facial redness was assessed at baseline and 4 weeks after intervention by clinical grading and by image-based analysis.Main outcome measures: The primary outcome measure was image-based facial quantification of redness using a research camera and software analysis system. The investigators performed an intention-to-treat analysis by including all subjects who were enrolled in the trial and received any study intervention.Differences were considered statistically significant after accounting for multiple comparisons. Effect sizes for clinical grading were calculated with a Hedges' g where indicated.Results: Twenty-eight participants completed the study and there were no reported adverse events.Based on clinical grading, facial redness intensity and distribution down trended in the polyherbal combination group after 4 weeks(P = 0.1). Under photographic image analysis, the polyherbal combination group had a significant decrease in redness of 40% compared to baseline(P = 0.03). The placebo and turmeric groups had no statistically significant changes in image analysis-based facial redness.Conclusion: Polyherbal combination tablet supplementation improved facial redness compared to the turmeric or placebo. Overall, our findings suggested further investigations into the effects of turmeric and polyherbal formulations in skin conditions associated with facial redness would be warranted.Trial registration: ClinicalTrials.gov identifier: NCT03065504. 展开更多
关键词 Turmeric CURCUMA longa AYURVEDA redness ERYTHEMA
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Ameliorating Effects of Delphinol®, Anthocyanin Standardized Maqui Berry Extract, on Skin Brightness and Redness in Japanese Females: A Randomized Double-Blind Placebo-Controlled Pilot Study
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作者 Norihito Shimizu Wakana Yamada +1 位作者 Kenchi Miyasaka Hiroshi Shimoda 《Journal of Cosmetics, Dermatological Sciences and Applications》 2020年第4期149-162,共14页
Maqui berries are wildly grown or cultivated in the Patagonian region in Chile. The berries contain large amounts of anthocyanins, especially delphinidin glycosides, which are strong anti-oxidants. We previously repor... Maqui berries are wildly grown or cultivated in the Patagonian region in Chile. The berries contain large amounts of anthocyanins, especially delphinidin glycosides, which are strong anti-oxidants. We previously reported that standardized maqui berry extract, which contained lots of anthocyanins, has ameliorative effects against dry eyes and visible light-induced photoreceptor cell damage. However, the influence of maqui berry extract on the human skin has not been evaluated even though many skin troubles are related to active oxygen species. Therefore, we conducted a randomized double-blind placebo-controlled pilot study with Delphinol<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&#174;</span></span>, a maqui berry extract standardized for anthocyanins, especially delphinidins and cyanidins, in healthy Japanese female subjects. Capsules containing Delphinol<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&#174;</span></span></span> (60 mg) or placebo were orally administered to subjects aged 27 to 57 years old for eight weeks. Skin conditions [pigmentation, redness, skin tone, wrinkles, texture, oil content, water content, trans epidermal water loss (TEWL), collagen score, dermal thickness, and elasticity] were measured before and after intervention. In the Delphinol<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&#174;</span></span></span> group, the saturation significantly increased after eight weeks and reddish spots significantly decreased after four weeks of intake. The collagen score, which decreases with age, slightly increased with age by Delphinol<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&#174;</span></span> ingestion for eight weeks. Thus, the anthocyanin-standardized maqui berry extract Delphinol<span style="white-space:nowrap;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&#174;</span></span></span></span> increased skin brightness and collagen content, and improved facial skin redness. This study suggests that the daily oral intake of maqui berry extract can help maintain a healthy facial condition. 展开更多
关键词 Maqui Berry Delphinidin Glucoside Anthocyanins SKIN BRIGHTNESS Saturation redness Collagen Score
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微生物采油技术的研究进展
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作者 曹功泽 李彩风 +2 位作者 郑文韬 汪卫东 王雪 《石油钻采工艺》 北大核心 2025年第1期1-13,共13页
微生物采油技术(MEOR)具有耗能低、环境友好等优势,但极端油藏环境(高温、高盐、厌氧)中高效驱油菌株的缺乏制约了微生物采油技术的应用。针对极端油藏环境,利用基因编辑技术优化微生物的耐热性和厌氧能力是微生物采油的技术瓶颈。利用... 微生物采油技术(MEOR)具有耗能低、环境友好等优势,但极端油藏环境(高温、高盐、厌氧)中高效驱油菌株的缺乏制约了微生物采油技术的应用。针对极端油藏环境,利用基因编辑技术优化微生物的耐热性和厌氧能力是微生物采油的技术瓶颈。利用基因工程对分离自极端油藏储层环境中的微生物进行定向改造,是获得微生物采油菌株的有效方式。从微生物采油的作用机理、应用现状以及发展方向三个方面对微生物采油技术进行了综述,并引入了酶法强化采油技术(EEOR)这一新概念,通过使用生物酶催化剂改变岩石物理性质,提高石油质量和开采效率。这些研究将有助于更好地理解油藏极端环境微生物的生态系统,并为其应用提供更好的科学依据。 展开更多
关键词 微生物采油 提高采收率 基因工程 耐厌氧 高温 Red/ET重组工程 酶法强化采油
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5G RedCap赋能智能电网,打造高效可靠解决方案 被引量:1
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作者 孙军涛 《通信企业管理》 2025年第2期51-56,共6页
RedCap(5G轻量化)是5G关键技术之一,它通过精简设备能力、降低复杂度等方式,在保留5G原生能力基础上,实现节约成本、降低功耗、缩小尺寸等目标,为5G进一步规模化应用提供保障。标准方面,2022年6月,3GPPR17冻结,标志着RedCap标准正式落地... RedCap(5G轻量化)是5G关键技术之一,它通过精简设备能力、降低复杂度等方式,在保留5G原生能力基础上,实现节约成本、降低功耗、缩小尺寸等目标,为5G进一步规模化应用提供保障。标准方面,2022年6月,3GPPR17冻结,标志着RedCap标准正式落地;2024年6月,R18冻结,RedCap标准获得增强。 展开更多
关键词 RED 智能电网 规模化应用 3GPP 降低功耗 解决方案 冻结 轻量化
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大肠杆菌OmpC响应银胁迫初探及生物信息学分析
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作者 沈舒楚 吴钰煌 +5 位作者 蔡丹 安皓月 伍中宝 王君 杜幼芹 邹黎黎 《中国测试》 北大核心 2025年第4期100-108,共9页
通过同源重组技术敲除大肠杆菌(Escherichia coli,E.coli)外膜孔蛋白C(outer membrane porin channel C,OmpC)编码基因ompC、OmpF编码基因ompF和PhoE编码基因phoE。连续监测ompC缺失株的生长及其对银离子的敏感性;运用生物信息学分析Omp... 通过同源重组技术敲除大肠杆菌(Escherichia coli,E.coli)外膜孔蛋白C(outer membrane porin channel C,OmpC)编码基因ompC、OmpF编码基因ompF和PhoE编码基因phoE。连续监测ompC缺失株的生长及其对银离子的敏感性;运用生物信息学分析OmpC的生物学特性。结果显示ompC、ompF和phoE缺失株构建成功,ompC、ompF和phoE缺失并不影响E.coli的生长代谢。相比于其他孔蛋白,OmpC蛋白缺失可显著提高E.coli抵御银离子胁迫的能力,与耐抗生素存在差异。生物信息学分析结果表示,OmpC的分子式为C1795H2676N482O577S4,由367个氨基酸组成,相对分子质量为40368.12,原子总数为5534,等电点为4.58;含有跨膜域,定位于细胞外膜中;二级结构中α-螺旋占比18.80%,β-折叠占比29.16%,β-转角占比6.81%,无规则卷曲占比45.23%;与银离子进行分子对接预测显示无对接位点。这为OmpC主要作为银离子入胞通道提供更多证据,可为解析E.coli应对银离子胁迫的机制奠定基础。 展开更多
关键词 大肠杆菌 λRed同源重组技术 银离子 OMPC 生物信息学分析
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Experimental Study of Selective Batch Bio-Adsorption for the Removal of Dyes in Industrial Textile Effluents 被引量:2
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作者 Zakaria Laggoun Amel Khalfaoui +3 位作者 Kerroum Derbal Amira Fadia Ghomrani Abderrezzaq Benalia Antonio Pizzi 《Journal of Renewable Materials》 2025年第1期127-146,共20页
This research aims to study the bio-adsorption process of two dyes,Cibacron Green H3G(CG-H3G)and Terasil Red(TR),in a single system and to bring them closer to the industrial textile discharge by a binary mixture of t... This research aims to study the bio-adsorption process of two dyes,Cibacron Green H3G(CG-H3G)and Terasil Red(TR),in a single system and to bring them closer to the industrial textile discharge by a binary mixture of two dyes(TR+CG-H3G).The Cockle Shell(CS)was used as a natural bio-adsorbent.The characterizations of CS were investigated by Fourier transform infrared(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDX)and Brunauer–Emmett–Teller(BET).The adsorption potential of Cockle Shells was tested in two cases(single and binary system)and determined by:contact time(0–60 min),bio-adsorption dose(3–15 g/L),initial concentration(10–300 mg/L),temperature(22–61°C)and pH solution(2–12).The study of bio-adsorption(equilibrium and kinetics)was conducted at 22°C.The kinetic studies demon-strated that a pseudo-second-order adsorption mechanism had a good correlation coefficient(R2≥0.999).The Langmuir isotherm modeling provided a well-defined description of TR and CG-H3G bio-adsorption on cockle shells,exhibiting maximum capacities of 29.41 and 3.69 mg/g respectively at 22°C.The thermodynamic study shows that the reaction between the TR,CG-H3G dyes molecules and the bio-adsorbent is exothermic,spontaneous in the range of 22–31°C with the aleatory character decrease at the solid-liquid interface.The study of selectivity in single and binary systems has been performed under optimal operating conditions using the industrial textile rejection pH(pH=6.04).CG-H3G dye is found to have a higher selectivity than TR in single(0–60 min)and binary systems with a range of 6–45 min,as shown by the selectivity measurement.It was discovered that CS has the capability to remove both CG-H3G and TR dyes in both simple and binary systems,making it a superior bio-adsorbent. 展开更多
关键词 Cockle shells bio-adsorption binary system dyes cibacron green terasil red selectivity
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Formation and Evolution of Stars and Galaxies in the Cosmic Environment 被引量:1
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作者 Cui-xiang Zhong 《Journal of Environmental Science and Engineering(B)》 2025年第2期53-64,共12页
With the advancement of astronomical observation technology,people have a deeper understanding of the formation and evolution of galaxies,but many details of our own Milky Way and other external galaxies are still unk... With the advancement of astronomical observation technology,people have a deeper understanding of the formation and evolution of galaxies,but many details of our own Milky Way and other external galaxies are still unknown.Therefore,by studying the formation and orbital transformation mechanism of satellites,planets and stars,the author puts forward a new theory on the formation and evolution of stars and galaxies,thus revealing the hierarchical structure of galaxies and the formation and evolution laws of main sequence stars,red giants,white dwarfs,black dwarfs,supernovae,neutron stars,black holes and quasars.Some special phenomena in the course of star formation and evolution,such as sunspots,flares,fast radio bursts and gamma-ray bursts,have also been revealed. 展开更多
关键词 SUNSPOT red giant White Dwarf SUPERNOVA neutron star QUASAR fast radio burst gamma-ray burst.
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Saturation effect on storage‑dissipation properties and failure characteristics of red sandstone:Energy mechanism of water in preventing rockburst 被引量:1
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作者 Yong Luo Jiancheng Huang +2 位作者 Wuxing Wu Xuefeng Si Chuanqi Zhu 《International Journal of Coal Science & Technology》 2025年第2期269-287,共19页
To investigate the effect of saturation on the storage-dissipation properties and failure characteristics of red sandstone,as well as the energy mechanism of rockburst prevention by water,a series of uniaxial compress... To investigate the effect of saturation on the storage-dissipation properties and failure characteristics of red sandstone,as well as the energy mechanism of rockburst prevention by water,a series of uniaxial compression and uniaxial loading–unloading tests were conducted under five saturation levels.The effect of saturation on the mechanical properties and elastic energy density was analyzed,and a method for obtaining peak energy density was proposed.The effect of saturation on the energy evolution was examined,and the energy mechanism of water in preventing rockburst was revealed.The results indicate that an increase in saturation of red sandstone decreases the input energy density,elastic energy density,dissipated energy density,peak strength and peak strain;the compaction phase of the stress–strain curve becomes shorter;the failure mode transitions from X-conjugate oblique shear to single oblique shear;the variation in the debris ejection trajectory is as follows:radiation→X-ray→oblique upward parabola→horizontal parabola→oblique downward parabola;the degree of failure intensity and fragmentation is decreased gradually.Elastic energy density is interconnected with both saturation and stress but independent of the loading path.Saturation exhibits a dual effect on the energy storage property,i.e.,increasing saturation increases the energy storage efficiency and reduces the energy storage capacity.The ratio of peak elastic energy density to peak input energy density remains constant irrespective of saturation levels.Water prevents rockburst by decreasing the energy storage capacity of surrounding rock,alleviating the stress of surrounding rock to reduce energy storage,and elevating the energy release threshold of high-energy surrounding rock.The findings of this study contribute to understanding the effect of water on rock failure from an energy perspective,as well as provide theoretical guidance for rockburst prevention by water in deep tunnels. 展开更多
关键词 Red sandstone SATURATION Energy properties Peak energy density Rockburst prevention
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Construction of eco-friendly dual carbon dots ratiometric fluorescence probe for highly selective and efficient sensing mercury ion 被引量:1
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作者 Yongli Liu Xiaoyan Su +5 位作者 Huanjia Liu Guifen Zhu Guobei Ge Yuxin Wang Penghui Zhou Qingxiang Zhou 《Journal of Environmental Sciences》 2025年第2期1-12,共12页
In present work,blue carbon dots(b-CDs)were derived from ammonium citrate and guanidine hydrochloride,and red carbon dots(r-CDs)were stemmed from malonate,ethylenediamine and meso-tetra(4-carboxyphenyl)porphin based o... In present work,blue carbon dots(b-CDs)were derived from ammonium citrate and guanidine hydrochloride,and red carbon dots(r-CDs)were stemmed from malonate,ethylenediamine and meso-tetra(4-carboxyphenyl)porphin based on facile hydrothermal method.Eco-friendly ratiometric fluorescence probe was innovatively constructed to effectively measure Hg2+utilizing b-CDs and r-CDs.The developed probe displayed two typical emission peaks at 450 nm from b-CDs and 650 nm from r-CDs under the excitation at 360 nm.Mercury ion has strong quenching effect on the fluorescence intensity at 450 nm due to the electron transfer process and the fluorescence change at 450 nm was used as the response signal,whereas the fluorescence intensity at 650 nm kept unchangeable which resulted from the chemical inertness between Hg^(2+)and r-CDs,serving as the reference signal in the sensing system.Under optimal circumstances,this probe exhibited an excellent linearity between the fluorescence response values of F450/F650 and Hg^(2+)concentrations over range of 0.01-10μmol/L,and the limit of detectionwas down to 5.3 nmol/L.Furthermore,this probe was successfully employed for sensing Hg^(2+)in practical environmental water samples with satisfied recoveries of 98.5%-105.0%.The constructed ratiometric fluorescent probe provided a rapid,environmental-friendly,reliable,and efficient platform for measuring trace Hg^(2+)in environmental field. 展开更多
关键词 Blue carbon dots Red carbon dots Electron transfer Hg^(2+) ECO-FRIENDLINESS
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Massive Outbreak of Red Sprites in South Asia Observed from the Tibetan Plateau 被引量:1
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作者 Hailiang HUANG Gaopeng LU +5 位作者 Angel AN Di XU Zhengwei CHENG Yongping WANG Yazhou CHEN Xin HUANG 《Advances in Atmospheric Sciences》 2025年第6期1247-1260,共14页
On 19 May 2022, an outbreak of 105 red sprites that occurred over South Asia was fortuitously recorded by two amateurs from a site in the southern Tibetan Plateau(TP), marking the highest number captured over a single... On 19 May 2022, an outbreak of 105 red sprites that occurred over South Asia was fortuitously recorded by two amateurs from a site in the southern Tibetan Plateau(TP), marking the highest number captured over a single thunderstorm in South Asia. Nearly half of these events involved dancing sprites, with an additional 16 uncommon secondary jets and at least four extremely rare green emissions called “ghosts” observed following the associated sprites. Due to the absence of the precise timing needed to identify parent lightning, a method based on satellite motion trajectories and star fields is proposed to infer video frame timestamps within an error of less than one second. After verifying 95 sprites from two videos, our method identified the parent lightning for 66 sprites(~70%). The sprite-producing strokes, mainly of positive polarity with peak currents exceeding +50 k A, occurred in the stratiform region of a mesoscale convective complex(MCC)that spanned the Ganges Plain to the southern TP, with a cloud area over 200 000 km2 and a minimum cloud-top black body temperature near 180 K. This observation confirms that thunderstorms in South Asia, akin to mesoscale convective systems(MCSs) in the Great Plains of the United States or coastal thunderstorms in Europe, can produce numerous sprites,including complex species. Our analysis bears important implications for characterizing thunderstorms above the southern TP and examining their physical and chemical effects on the adjacent regions, as well as the nature of the coupling between the troposphere and middle-upper atmosphere in this region. 展开更多
关键词 red sprites Tibetan Plateau South Asia parent lightning strokes satellite trajectory mesoscale convective complex
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Bimetallic Ni_(x)Fe_(2-x)P cocatalyst with tunable electronic structure for enhanced photocatalytic benzyl alcohol oxidation coupled with H_(2)evolution over red phosphorus 被引量:1
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作者 Shuang Li Haili Lin +5 位作者 Xuemei Jia Xin Jin Qianlong Wang Xinyue Li Shifu Chen Jing Cao 《Chinese Journal of Catalysis》 2025年第3期363-377,共15页
Although bimetallic phosphide cocatalysts have attracted considerable interest in photocatalysis research owing to their advantageous thermodynamic characteristics,superstable and efficient cocatalysts have rarely bee... Although bimetallic phosphide cocatalysts have attracted considerable interest in photocatalysis research owing to their advantageous thermodynamic characteristics,superstable and efficient cocatalysts have rarely been produced through the modulation of their structure and composition.In this study,a series of bimetallic nickel-iron phosphide(Ni_(x)Fe_(2-x)P,where 0<x<2)cocatalysts with controllable structures and overpotentials were designed by adjusting the atomic ratio of Ni/Fe onto nonmetallic elemental red phosphorus(RP)for the photocatalytic selective oxidation of benzyl alcohol(BA)coupled with hydrogen production.The catalysts exhibited an outstanding photocatalytic activity for benzaldehyde and a high H_(2)yield.The RP regulated by bimetallic phosphide cocatalysts(Ni_(x)Fe_(2-x)P)demonstrated higher photocatalytic oxidation-reduction activity than that regulated by monometallic phosphide cocatalysts(Ni_(2)P and Fe2P).In particular,the RP regulated by Ni_(1.25)Fe_(0.75)P exhibited the best photocatalytic performance.In addition,experimental and theoretical calculations further illustrated that Ni_(1.25)Fe_(0.75)P,with the optimized electronic structure,possessed good electrical conductivity and provided strong adsorption and abundant active sites,thereby accelerating electron migration and lowering the reaction energy barrier of RP.This finding offers valuable insights into the rational design of highly effective cocatalysts aimed at optimizing the photocatalytic activity of composite photocatalysts. 展开更多
关键词 Bimetallic phosphides cocatalyst Composition regulation Red phosphorus Selective oxidation of benzyl alcohol H_(2)
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Mesoscopic fracture damage evolution and fractal damage constitutive model of heat-treated red sandstone under direct tensile impact loadings 被引量:1
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作者 Shi Liu Yu Jia +1 位作者 Yue Zhai Shaoxu Hao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期323-340,共18页
Understanding the mesoscopic tensile fracture damage of rock is the basis of evaluating the deterioration process of mechanical properties of heat-damaged rock. For this, tensile tests of rocks under high-temperature ... Understanding the mesoscopic tensile fracture damage of rock is the basis of evaluating the deterioration process of mechanical properties of heat-damaged rock. For this, tensile tests of rocks under high-temperature treatment were conducted with a ϕ75 mm split Hopkinson tension bar (SHTB) to investigate the mesoscopic fracture and damage properties of rock. An improved scanning electron microscopy (SEM) experimental method was used to analyze the tensile fracture surfaces of rock samples. Qualitative and quantitative analyses were performed to assess evolution of mesoscopic damage of heat-damaged rock under tensile loading. A constitutive model describing the mesoscopic fractal damage under thermo-mechanical coupling was established. The results showed that the high temperatures significantly reduced the tensile strength and fracture surface roughness of the red sandstone. The three-dimensional (3D) reconstruction of the fracture surface of the samples that experienced tensile failure at 900 °C showed a flat surface. The standard deviation of elevation and slope angle of specimen fracture surface first increased and then decreased with increasing temperature. The threshold for brittle fracture of the heat-damaged red sandstone specimens was 600 °C. Beyond this threshold temperature, local ductile fracture occurred, resulting in plastic deformation of the fracture surface during tensile fracturing. With increase of temperature, the internal meso-structure of samples was strengthened slightly at first and then deteriorated gradually, which was consistent with the change of macroscopic mechanical properties of red sandstone. The mesoscopic characteristics, such as the number, mean side length, maximum area, porosity, and fractal dimension of crack, exhibited an initial decline, followed by a gradual increase. The development of microcracks in samples had significant influence on mesoscopic fractal dimension. The mesoscopic fractal characteristics were used to establish a mesoscopic fractal damage constitutive model for red sandstone, and the agreement between the theoretical and experimental results validated the proposed model. 展开更多
关键词 High temperature rock mechanics Dynamic direct tension Red sandstone Mesoscopic fracture mechanism Fractal damage constitutive model
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Enhanced red upconversion luminescence induced by Yb-Fe dimer for bifunctional biological applications in optical thermometry and photothermics 被引量:1
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作者 Yue Guo Xiao-Ping Jiang +2 位作者 Xiao-Yu Yue Li-Xi Wang Qi-Tu Zhang 《Rare Metals》 2025年第2期1231-1242,共12页
The enhancement of the intensity of red upconversion(UC)emission has significant implications for biological applications.In KZnF_(3):Yb^(3+),Er^(3+)which inherently produces high-purity red emission,the introduction ... The enhancement of the intensity of red upconversion(UC)emission has significant implications for biological applications.In KZnF_(3):Yb^(3+),Er^(3+)which inherently produces high-purity red emission,the introduction of Fe^(3+)markedly improves the UC intensity by a factor of 13.The mechanism behind the enhanced UC red luminescence is deduced to originate from the Yb^(3+)-Fe^(3+)dimer,as determined by first principle calculation and analysis of UC luminescence properties.The thermometry performance,based on splitting peaks of red emission,demonstrated enhanced temperature sensitivity at lower ranges.Exploring the photothermal properties,it was observed that temperature exhibited a linear correlation with pump power under a 980 nm laser,achieving levels up to 48℃.This temperature range is ideal for applications in mild photothermal therapy(MPTT).This work elucidates the material’s potential in advanced biological applications,merging optical thermometry and photothermics,indicating its multifunctional utility. 展开更多
关键词 Upconversion luminescence(UC) Red emission Er^(3+) Temperature sensing Mild photothermal therapy(MPTT)
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Solar cycles during the seventeenth century revealed by equatorial aurora records
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作者 Yong Wei LiMei Yan 《Earth and Planetary Physics》 EI CAS 2025年第1期182-187,共6页
Solar cycles are fundamental to astrophysics,space exploration,technological infrastructure,and Earth's climate.A better understanding of these cycles and their history can aid in risk mitigation on Earth,while al... Solar cycles are fundamental to astrophysics,space exploration,technological infrastructure,and Earth's climate.A better understanding of these cycles and their history can aid in risk mitigation on Earth,while also deepening our knowledge of stellar physics and solar system dynamics.Determining the solar cycles between 1600 and 1700-especially the post-1645 Maunder Minimum,characterized by significantly reduced solar activity-poses challenges to existing solar activity proxies.This study utilizes a new red equatorial auroral catalog from ancient Korean texts to establish solar cycle patterns from 1623 to 1700.Remarkably,a further reevaluation of the solar cycles between 1610 and 1755 identified a total of 13 cycles,diverging from the widely accepted record of 12 cycles during that time.This research enhances our understanding of historical solar activity,and underscores the importance of integrating diverse historical sources into modern analyses. 展开更多
关键词 solar cycle Maunder Minimum solar activity red equatorial aurora West Pacific geomagnetic anomaly
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Pretreatment red blood cell distribution width as a predictive marker for postoperative complications after laparoscopic pancreatoduodenectomy
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作者 Xian-Rang Cao Yin-Long Xu +4 位作者 Jia-Wei Chai Kai Zheng Jun-Jie Kong Jun Liu Shun-Zhen Zheng 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期143-157,共15页
BACKGROUND Red blood cell distribution width(RDW)is associated with the development and progression of various diseases.AIM To explore the association between pretreatment RDW and short-term outcomes after laparoscopi... BACKGROUND Red blood cell distribution width(RDW)is associated with the development and progression of various diseases.AIM To explore the association between pretreatment RDW and short-term outcomes after laparoscopic pancreatoduodenectomy(LPD).METHODS A total of 804 consecutive patients who underwent LPD at our hospital between March 2017 and November 2021 were retrospectively analyzed.Correlations between pretreatment RDW and clinicopathological characteristics and short-term outcomes were investigated.RESULTS Patients with higher pretreatment RDW were older,had higher Eastern Cooperative Oncology Group scores and were associated with poorer short-term outcomes than those with normal RDW.High pretreatment RDW was an independent risk factor for postoperative complications(POCs)(hazard ratio=2.973,95%confidence interval:2.032-4.350,P<0.001)and severe POCs of grade IIIa or higher(hazard ratio=3.138,95%confidence interval:2.042-4.824,P<0.001)based on the Clavien-Dino classification system.Subgroup analysis showed that high pretreatment RDW was an independent risk factor for Clavien-Dino classi-fication grade IIIb or higher POCs,a comprehensive complication index score≥26.2,severe postoperative pancreatic fistula,severe bile leakage and severe hemorrhage.High pretreatment RDW was positively associated with the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio and was negatively associated with albumin and the prognostic nutritional index.CONCLUSION Pretreatment RDW was a special parameter for patients who underwent LPD.It was associated with malnutrition,severe inflammatory status and poorer short-term outcomes.RDW could be a surrogate marker for nutritional and inflammatory status in identifying patients who were at high risk of developing POCs after LPD. 展开更多
关键词 BIOMARKER Laparoscopic pancreatoduodenectomy Postoperative complication Red blood cell distribution width Short-term outcomes
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Removal of elemental mercury from coal combustion flue gas by sodium halides impregnated red mud
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作者 MUHAMMAD Sarfraz LI Yang +3 位作者 YANG He JIN Lijun LI Dekang HU Haoquan 《燃料化学学报(中英文)》 北大核心 2025年第1期53-69,共17页
Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated wi... Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated with sodium halides(NaBr and NaI)are presented to capture elemental mercury(Hg^(0))from flue gas.The modified RM underwent comprehensive characterization,including analysis of its textural qualities,crystal structure,chemical composition,and thermal properties.The results indicate that the halide impregnation substantially impacts the surface area and pore size of the RM.Hg^(0) removal performance was evaluated on a fixed-bed reactor in simulated flue gas(consisting of N_(2),O_(2),CO_(2),NO and SO_(2),etc.)on a modified RM.At an optimal adsorption temperature of 160℃,NaI-modified sorbent(RMI5)offers a removal efficiency of 98%in a mixture of gas,including O_(2),NO and HCl.Furthermore,pseudo-second-order model fitting results demonstrate the chemisorption mechanism for the adsorption of Hg^(0) in kinetic investigations. 展开更多
关键词 mercury removal red mud sodium halides IMPREGNATION flue gas
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Incorporating red blanket protocol within code crimson:Streamlining definitive trauma care amid the chaos
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作者 Sohil Pothiawala Savitha Bhagvan Andrew MacCormick 《World Journal of Critical Care Medicine》 2025年第1期14-19,共6页
The care of a patient involved in major trauma with exsanguinating haemorrhage is time-critical to achieve definitive haemorrhage control,and it requires coordinated multidisciplinary care.During initial resuscitation... The care of a patient involved in major trauma with exsanguinating haemorrhage is time-critical to achieve definitive haemorrhage control,and it requires coordinated multidisciplinary care.During initial resuscitation of a patient in the emergency department(ED),Code Crimson activation facilitates rapid decisionmaking by multi-disciplinary specialists for definitive haemorrhage control in operating theatre(OT)and/or interventional radiology(IR)suite.Once this decision has been made,there may still be various factors that lead to delay in transporting the patient from ED to OT/IR.Red Blanket protocol identifies and addresses these factors and processes which cause delay,and aims to facilitate rapid and safe transport of the haemodynamically unstable patient from ED to OT,while minimizing delay in resuscitation during the transfer.The two processes,Code Crimson and Red Blanket,complement each other.It would be ideal to merge the two processes into a single protocol rather than having two separate workflows.Introducing these quality improvement strategies and coor-dinated processes within the trauma framework of the hospitals/healthcare systems will help in further improving the multi-disciplinary care for the complex trauma patients requiring rapid and definitive haemorrhage control. 展开更多
关键词 Red blanket protocol Code crimson HAEMORRHAGE Trauma
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Exploring dealkalization and Cr removal from red mud through freeze-thaw and acid washing:An experimental approach
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作者 ShengJie Liu DaHu Rui +4 位作者 WeiDong Pan Jun Zhang MingChang Ji HaiYang Zhang DanYang Wang 《Research in Cold and Arid Regions》 2025年第1期27-33,共7页
Red mud(RM) is an industrial solid waste produced during the extraction of alumina from bauxite.The strong alkaline and heavy metal leaching issues are the primary factors limiting its utilization.This paper proposes ... Red mud(RM) is an industrial solid waste produced during the extraction of alumina from bauxite.The strong alkaline and heavy metal leaching issues are the primary factors limiting its utilization.This paper proposes a method for dealkalization and chromium(Cr) removal by repeated freeze and thaw to enhance the comprehensive utilization rate of RM.This study focused on the Bayer RM and investigated the effects of freeze-thaw(FT)-acid washing(AW) for dealkalization and Cr removal.The variables were the eluent concentration and FT cycles.The results showed that the synergistic action of FT-AW significantly improved the efficiency of dealkalization and Cr removal.After five FT cycles with 0.5 mol/L oxalic acid,the dealkalization and Cr removal rates reached 97.5% and 65.38%,respectively,16.1% and 7.40% higher than those achieved at room temperature.The repeated FT disrupted the structure of the RM particles,leading to an increase in the pore space between the soil particles.This enables complete eluent contact and reaction with Cr and alkali,thereby enhancing the removal rate.The FT-AW process is suitable for practical engineering applications.It offers a novel method for RM dealkalization and Cr removal by using the FT alternation phenomena in seasonally frozen regions. 展开更多
关键词 Red mud FREEZE-THAW Acid washing DEALKALIZATION CHROMIUM
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Wheels of Opportunity Chinese motorcycles create job opportunities in Zambia
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作者 《ChinAfrica》 2025年第11期48-50,共3页
In the busy streets of Lusaka,Zambia’s capital,Joel Kangwa fired up his red Haojue.It is not just a motorbike.It is the reason he wakes up each morning with purpose.He kicked the starter and the engine responded with... In the busy streets of Lusaka,Zambia’s capital,Joel Kangwa fired up his red Haojue.It is not just a motorbike.It is the reason he wakes up each morning with purpose.He kicked the starter and the engine responded with a low growl.“Working as a courier on my motorbike is a dream come true.I now earn more than double what I used to make as a salesman in the industrial area,”he said. 展开更多
关键词 Haojue job opportunities motorcycles courier service Zambia Lusaka red haojueit
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