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Precise and non-destructive approach for identifying the real concentration based on cured cemented paste backfill using hyperspectral imaging
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作者 Qing Na Qiusong Chen Aixiang Wu 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期116-128,共13页
Cemented paste backfill(CPB)is a technology that achieves safe mining by filling the goaf with waste rocks,tailings,and other materials.It is an inevitable choice to deal with the development of deep and highly diffic... Cemented paste backfill(CPB)is a technology that achieves safe mining by filling the goaf with waste rocks,tailings,and other materials.It is an inevitable choice to deal with the development of deep and highly difficult mines and meet the requirements of environmental protection and safety regulations.It promotes the development of a circular economy in mines through the development of lowgrade resources and the resource utilization of waste,and extends the service life of mines.The mass concentration of solid content(abbreviated as“concentration”)is a critical parameter for CPB.However,discrepancies often arise between the on-site measurements and the pre-designed values due to factors such as groundwater inflow and segregation within the goaf,which cannot be evaluated after the solidification of CPB.This paper innovatively provides an in-situ non-destructive approach to identify the real concentration of CPB after curing for certain days using hyperspectral imaging(HSI)technology.Initially,the spectral variation patterns under different concentration conditions were investigated through hyperspectral scanning experiments on CPB samples.The results demonstrate that as the CPB concentration increases from 61wt%to 73wt%,the overall spectral reflectance gradually increases,with two distinct absorption peaks observed at 1407 and 1917 nm.Notably,the reflectance at 1407 nm exhibited a strong linear relationship with the concentration.Subsequently,the K-nearest neighbors(KNN)and support vector machine(SVM)algorithms were employed to classify and identify different concentrations.The study revealed that,with the KNN algorithm,the highest accuracy was achieved when K(number of nearest neighbors)was 1,although this resulted in overfitting.When K=3,the model displayed the optimal balance between accuracy and stability,with an accuracy of 95.03%.In the SVM algorithm,the highest accuracy of 98.24%was attained with parameters C(regularization parameter)=200 and Gamma(kernel coefficient)=10.A comparative analysis of precision,accuracy,and recall further highlighted that the SVM provided superior stability and precision for identifying CPB concentration.Thus,HSI technology offers an effective solution for the in-situ,non-destructive monitoring of CPB concentration,presenting a promising approach for optimizing and controlling CPB characteristic parameters. 展开更多
关键词 cemented paste backfill concentration hyperspectral imaging non-destructive testing
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An effective deep-learning prediction of Arctic sea-ice concentration based on the U-Net model
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作者 Yifan Xie Ke Fan +2 位作者 Hongqing Yang Yi Fan Shengping He 《Atmospheric and Oceanic Science Letters》 2026年第1期34-40,共7页
Current shipping,tourism,and resource development requirements call for more accurate predictions of the Arctic sea-ice concentration(SIC).However,due to the complex physical processes involved,predicting the spatiote... Current shipping,tourism,and resource development requirements call for more accurate predictions of the Arctic sea-ice concentration(SIC).However,due to the complex physical processes involved,predicting the spatiotemporal distribution of Arctic SIC is more challenging than predicting its total extent.In this study,spatiotemporal prediction models for monthly Arctic SIC at 1-to 3-month leads are developed based on U-Net-an effective convolutional deep-learning approach.Based on explicit Arctic sea-ice-atmosphere interactions,11 variables associated with Arctic sea-ice variations are selected as predictors,including observed Arctic SIC,atmospheric,oceanic,and heat flux variables at 1-to 3-month leads.The prediction skills for the monthly Arctic SIC of the test set(from January 2018 to December 2022)are evaluated by examining the mean absolute error(MAE)and binary accuracy(BA).Results showed that the U-Net model had lower MAE and higher BA for Arctic SIC compared to two dynamic climate prediction systems(CFSv2 and NorCPM).By analyzing the relative importance of each predictor,the prediction accuracy relies more on the SIC at the 1-month lead,but on the surface net solar radiation flux at 2-to 3-month leads.However,dynamic models show limited prediction skills for surface net solar radiation flux and other physical processes,especially in autumn.Therefore,the U-Net model can be used to capture the connections among these key physical processes associated with Arctic sea ice and thus offers a significant advantage in predicting Arctic SIC. 展开更多
关键词 Arctic sea-ice concentration Deep-learning prediction U-Net model CFSv2 NorCPM
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Simple and universal method in designs of high-efficiency diffractive optical elements for spectrum separation and beam concentration 被引量:2
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作者 徐文琪 林冬风 +8 位作者 许信 叶佳声 王新柯 冯胜飞 孙文峰 韩鹏 张岩 孟庆波 杨国桢 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期89-95,共7页
Diffractive optical elements(DOEs) with spectrum separation and beam concentration(SSBC) functions have important applications in solar cell systems. With the SSBC DOEs, the sunlight radiation is divided into seve... Diffractive optical elements(DOEs) with spectrum separation and beam concentration(SSBC) functions have important applications in solar cell systems. With the SSBC DOEs, the sunlight radiation is divided into several wave bands so as to be effectively absorbed by photovoltaic materials with different band gaps. A new method is proposed for designing high-efficiency SSBC DOEs, which is physically simple, numerically fast, and universally applicable. The SSBC DOEs are designed by the new design method, and their performances are analyzed by the Fresnel diffraction integral method.The new design method takes two advantages over the previous design method. Firstly, the optical focusing efficiency is heightened by up to 10%. Secondly, focal positions of all the designed wavelengths can be designated arbitrarily and independently. It is believed that the designed SSBC DOEs should have practical applications to solar cell systems. 展开更多
关键词 diffractive optical element spectrum separation and beam concentration optical focusing efficiency solar cell system
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Disparities in precipitation effects on PM_(2.5)mass concentrations and chemical compositions:Insights from online monitoring data in Chengdu 被引量:1
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作者 Yi Li Li Zhou +7 位作者 Hefan Liu Song Liu Miao Feng Danlin Song Qinwen Tan Hongbin Jiang Sophia Zuoqiu Fumo Yang 《Journal of Environmental Sciences》 2025年第10期421-434,共14页
Precipitation plays a pivotal role in wet deposition,significantly affecting aerosol purification.The efficacy of precipitation in removing aerosols depends on its type and the characteristics of the particulates invo... Precipitation plays a pivotal role in wet deposition,significantly affecting aerosol purification.The efficacy of precipitation in removing aerosols depends on its type and the characteristics of the particulates involved.However,further research is necessary to fully understand how precipitation impacts PM_(2.5)components.This study utilized high-temporalresolution data on PM_(2.5),its components and meteorological factors to examine varying responses influenced by precipitation intensity and duration.The findings indicate that increased rainfall intensity and duration enhance PM_(2.5)and its constituents removal efficiency.Specifically,longer precipitation periods significantly improve PM_(2.5)purification,especially with drizzle and light rain.Moreover,there is a direct correlation between preprecipitation PM_(2.5)levels and its scavenging rates,with drizzle potentially exacerbating PM_(2.5)pollution under cleaner conditions(≤35μg/m^(3)).Seasonally,the efficacy of removing PM_(2.5)components varies notably in response to drizzle and light rain.In spring,higher PM_(2.5)levels after drizzlewere primarily due to increased organic carbon concentrations favored by higher relative humidity and lower pH conditions compared to other seasons,conducive to secondary organic aerosol production.Lower wind speeds and higher temperatures further contribute to water-soluble organic carbon accumulation.Daytime and nighttime precipitation exerted differing influences on PM_(2.5)components,particularly in spring where daytime drizzle and light rain significantly increased PM_(2.5)and its constituents,notably NO_(3)-,potentially associated with phase distribution changes between gas and aerosol phases in low-temperature,high-RH conditions compared to nighttime.These results propose a dualimpact mechanism of precipitation on PM_(2.5)and provide scientific basis for designing effective control strategies. 展开更多
关键词 PRECIPITATION PM_(2.5)mass concentrations Scavenging rate Chemical components Chengdu
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Different extractable pools of Cd and Pb in agricultural soil under amendments:Water-soluble concentration sensitively indicates metal availability 被引量:1
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作者 Zidi Wang Wenyao Tang +8 位作者 Xiaodong Ding Qiang Dong Yingying Guo Guangliang Liu Yanwei Liu Yong Liang Yongguang Yin Yong Cai Guibin Jiang 《Journal of Environmental Sciences》 2025年第4期297-308,共12页
Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies... Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies. 展开更多
关键词 Heavy metals Water-soluble concentrations Enriched stable isotopes Soil amendments Sequential extraction Soil pH
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Vedolizumab serum trough concentrations with and without thiopurines in ulcerative colitis: The prospective VIEWS pharmacokinetics study
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作者 Thanaboon Chaemsupaphan Aviv Pudipeddi +4 位作者 Hui-Yu Lin Sudarshan Paramsothy Viraj C Kariyawasam Melissa Kermeen Rupert W Leong 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期102-112,共11页
BACKGROUND Ulcerative colitis(UC)is a chronic inflammatory condition requiring continuous treatment and monitoring.There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thio... BACKGROUND Ulcerative colitis(UC)is a chronic inflammatory condition requiring continuous treatment and monitoring.There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thiopurines on vedolizumab trough concentrations is unknown.AIM To investigate the exposure-response relationship of vedolizumab and the impact of thiopurine withdrawal in UC patients who have achieved sustained clinical and endoscopic remission during maintenance therapy.METHODS This is a post-hoc analysis of prospective randomized clinical trial(VIEWS)involving UC patients across 8 centers in Australia from 2018 to 2022.Patients in clinical and endoscopic remission were randomized to continue or withdraw thiopurine while receiving vedolizumab.We evaluated vedolizumab serum trough concentrations,presence of anti-vedolizumab antibodies,and clinical outcomes over 48 weeks to assess exposure-response asso-ciation and impact of thiopurine withdrawal.RESULTS There were 62 UC participants with mean age of 43.4 years and 42%were females.All participants received vedolizumab as maintenance therapy with 67.7%withdrew thiopurine.Vedolizumab serum trough concentrations remained stable over 48 weeks regardless of thiopurine use,with no anti-vedolizumab antibodies detected.Pa-tients with clinical remission had higher trough concentrations at week 48.In quartile analysis,a threshold of>11.3μg/mL was associated with sustained clinical remission,showing a sensitivity of 82.4%,specificity of 60.0%,and an area of receiver operating characteristic of 0.71(95%CI:0.49-0.93).Patients discontinuing thiopurine required higher vedolizumab concentrations for achieving remission.CONCLUSION A positive exposure-response relationship between vedolizumab trough concentrations and UC outcomes suggests that monitoring drug levels may be beneficial.While thiopurine did not influence vedolizumab levels,its with-drawal may necessitate higher vedolizumab trough concentrations to maintain remission. 展开更多
关键词 PHARMACOKINETIC Vedolizumab THIOPURINE Ulcerative colitis Trough concentration Antibody Inflammatory bowel diseases
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Impact of Pollutant Concentration and Particle Deposition on the Radiative Flow of Casson-Micropolar Fluid between Parallel Plates
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作者 Ghaliah Alhamzi Badr Saad T.Alkahtani +2 位作者 Ravi Shanker Dubey Vinutha Kalleshachar Neelima Nizampatnam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期665-690,共26页
Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing po... Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing pollution scales is made easier by analysing waste discharge concentrations.The waste discharge concentration analysis is useful for assessing how effectively wastewater treatment techniques reduce pollution levels.This study aims to explore the Casson micropolar fluid flow through two parallel plates with the influence of pollutant concentration and thermophoretic particle deposition.To explore the mass and heat transport features,thermophoretic particle deposition and thermal radiation are considered.The governing equations are transformed into ordinary differential equations with the help of suitable similarity transformations.The Runge-Kutta-Fehlberg’s fourthfifth order technique and shooting procedure are used to solve the reduced set of equations and boundary conditions.The integration of a neural network model based on the Levenberg-Marquardt algorithm serves to improve the accuracy of predictions and optimize the analysis of parameters.Graphical outcomes are displayed to analyze the characteristics of the relevant dimensionless parameters in the current problem.Results reveal that concentration upsurges as the micropolar parameter increases.The concentration reduces with an upsurge in the thermophoretic parameter.An upsurge in the external pollutant source variation and the local pollutant external source parameters enhances mass transport.The surface drag force declines for improved values of porosity and micropolar parameters. 展开更多
关键词 Micropolar fluid thermal radiation porous medium thermophoretic particle deposition waste discharge concentration
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Effect of Coffee Aroma on Cerebral Activity during Concentration Tasks
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作者 Moemi Matsuo Taiyo Ichibakase +2 位作者 Hikaru Suyama Runa Takahara Takashi Higuchi 《Open Journal of Applied Sciences》 2025年第1期137-146,共10页
Caffeine has been shown to reduce various health risks, such as diabetes, obesity, and vascular diseases, and it may provide health benefits when consumed in moderate amounts, such as three to four cups per day. Howev... Caffeine has been shown to reduce various health risks, such as diabetes, obesity, and vascular diseases, and it may provide health benefits when consumed in moderate amounts, such as three to four cups per day. However, caffeine may exhibit harmful effects depending on the dose. Although the health benefits and disadvantages of caffeine intake have been studied, the effects of caffeine’s aroma have hardly been studied. This study aimed to examine the impact of caffeine scent on brain activity during cognitive tasks using electroencephalography (EEG). This study included 30 healthy young adults. We investigated cerebral activity using EEG during the concentration tasks. Participants performed tasks under pre- and post-conditions, including drinking coffee, smelling coffee, or drinking water. The number of correct responses and reaction times were calculated for each task, and mean power levels were analyzed. A linear mixed model was applied with “performance”, “ROI”, and “wave band” to examine the effects of conditions and timing. Significant differences were observed in left-frontal θ power (coffee α power (coffee P θ between pre- and post-task during water conditions (pre α on the frontal lobe and higher θ are associated with improved arousal and cognitive functions. Drinking coffee reduced α power, whereas smelling coffee or drinking water increased θ power. Therefore, drinking coffee, smelling coffee, and drinking water may affect cerebral activities and enhance cognitive performance. 展开更多
关键词 COFFEE CAFFEINE concentration ELECTROENCEPHALOGRAPHY Brain Function NEUROIMAGING
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A Review on High-Efficiency Transfer of Graphene Films Free from Defects and Contamination
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作者 Wenhao Yin Chong Liu Jingmin Li 《Energy & Environmental Materials》 2025年第4期227-242,共16页
Graphene,owing to its exceptional electronic,optical,thermal,and mechanical properties,has emerged as a highly promising material.Currently,the synthesis of large-area graphene films on metal substrates via chemical v... Graphene,owing to its exceptional electronic,optical,thermal,and mechanical properties,has emerged as a highly promising material.Currently,the synthesis of large-area graphene films on metal substrates via chemical vapor deposition remains the predominant approach for producing high-quality graphene.To realize the potential applications of graphene,it is essential to transfer graphene films to target substrates in a manner that is non-destructive,clean,and efficient,as this significantly affects the performance of graphene devices.This review examines the current methods for graphene transfer from three perspectives:non-destructive transfer,clean transfer,and high-efficiency transfer.It analyzes and compares the advancements and limitations of various transfer techniques.Finally,the review identifies the key challenges faced by current graphene transfer methods and anticipates future developmental prospects. 展开更多
关键词 clean transfer defect-free transfer high-efficiency transfer of graphene
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Research Progress on High-efficiency Cultivation Techniques of Blueberry and Its Development Potential in Under-forest Economy
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作者 Haineng LIN Yuzhen YU +1 位作者 Hubo JIANG Ting ZHANG 《Asian Agricultural Research》 2025年第7期12-16,共5页
Through literature analysis and case study, the introduction history, variety selection (high bush, half high bush, low bush) and regional cultivation techniques of blueberry in China were summarized, and the practica... Through literature analysis and case study, the introduction history, variety selection (high bush, half high bush, low bush) and regional cultivation techniques of blueberry in China were summarized, and the practical effects of precision cultivation (water and fertilizer integration, wild planting) and under-forest economic model (forest-blueberry-fungus system, ecological tourism) were evaluated. It provided a technical reference for expanding the planting scale of blueberry and improving the fruit quality. 展开更多
关键词 BLUEBERRY high-efficiency cultivation techniques Under-forest economy Rural revitalization
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Terpolymers of alkyl methacrylate-trans anethole-1,2,3,6-tetrahydrophthalic anhydride copolymers:A low dosage and high-efficiency cold flow improver for diesel fuel
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作者 Bowen Xu Jiahao Chen +3 位作者 Lulu Cui Xinyue Li Yuan Xue Sheng Han 《Chinese Chemical Letters》 2025年第5期606-609,共4页
The addition of cold flow improvers(CFIs)is considered as the optimum strategy to improve the cold flow properties(CFPs)of diesel fuels,but this strategy is always limited by the required large dosage.To obtain low-do... The addition of cold flow improvers(CFIs)is considered as the optimum strategy to improve the cold flow properties(CFPs)of diesel fuels,but this strategy is always limited by the required large dosage.To obtain low-dosage and high-efficiency CFIs for diesel,1,2,3,6-tetrahydrophthalic anhydride(THPA)was introduced as a third and polar monomer to enhance the depressive effects of alkyl methacrylatetrans anethole copolymers(C_(14)MC-TA).The terpolymers of alkyl methacrylate-trans anethole-1,2,3,6-tetrahydrophthalic anhydride(C_(14)MC-TA-THPA)were synthesized and compared with the binary copolymers of C_(14)MC-TA and alkyl methacrylate-1,2,3,6-tetrahydrophthalic anhydride(C_(14)MC-THPA).Results showed that C_(14)MC-THPA achieved the best depressive effects on the cold filter plugging point(CFPP)and solid point(SP)by 11℃and 16℃at a dosage of 1250 mg/L and monomer ratio of 6:1,while 1500mg/L C_(14)MC-TA(1:1)reached the optimal depressive effects on the CFPP and SP by 12℃and 18℃.THPA introduction significantly improved the depressive effects of C_(14)MC-TA.Lower dosages of C_(14)MCTA-THPA in diesel exerted better improvement effects on the CFPP and SP than that of C_(14)MC-TA and C_(14)MC-THPA.When the monomer ratio and dosage were 6:0.6:0.4 and 1000 mg/L,the improvement effect of C_(14)MC-TA-THPA on diesel reached the optimum level,and the CFPP and SP were reduced by 13℃and 19℃,respectively.A 3D nonlinear surface diagram fitted by a mathematical model was also used for the first time to better understand the relationships of monomer ratios,dosages,and depressive effects of CFIs in diesel.Surface analysis results showed that C_(14)MC-TA-THPA achieved the optimum depressive effects at a monomer ratio of 6:0.66:0.34 and dosage of 1000 mg/L,and the CFPP and SP decreased by 14℃ and 19℃,respectively.The predicted results were consistent with the actual ones.Additionally,the improvement mechanism of these copolymers in diesel was also explored. 展开更多
关键词 Diesel fuel high-efficiency Cold flow properties Cold flow improvers Mathematical model
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ON THE CONCENTRATION OF STANDING WAVES FOR NLS EQUATION WITH POINT-DIPOLE POTENTIAL
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作者 Jun WANG Xiaoguang LI 《Acta Mathematica Scientia》 2025年第4期1265-1283,共19页
We study the following minimization problem d_(p)(M_(p)=∫_(R^(n))|▽u|^(2)-c|u|^(2)/|x|^(2)+V(x)|u|^(2)dx-2/p+2∫_(R^(N))|u|^p+2dx.when=p=p^(*):=4/N,,the precise concentration behavior of minimizers is analyzed as M_... We study the following minimization problem d_(p)(M_(p)=∫_(R^(n))|▽u|^(2)-c|u|^(2)/|x|^(2)+V(x)|u|^(2)dx-2/p+2∫_(R^(N))|u|^p+2dx.when=p=p^(*):=4/N,,the precise concentration behavior of minimizers is analyzed as M_(p^(*))↗‖Q_(p^(*))‖_(L^(2)),where Q_(p^(*))is the unique radially positive solution of-Δφ-cφ/|x|^(2-|φ|^(p^(*)+1)φ=0.When 0<p<p^(*)we prove that all minimizers must blow up if lim p→p^(*)M_(p)≥‖Q_(p^(*))‖L^(2).On his argument,the detailed concentration behavior of minimizers is established as p↗p^(*). 展开更多
关键词 minimization problem MINIMIZERS concentration behavior
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A light-powered molecular pump achieving transmembrane concentration gradient
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作者 Man Wu Chuandong Jia 《Chinese Journal of Structural Chemistry》 2025年第4期12-13,共2页
According to the second law of thermodynamics,spontaneous chemical processes will ultimately reach the equilibrium state with the lowest energy.However,in biological systems,there are numerous highenergy states far fr... According to the second law of thermodynamics,spontaneous chemical processes will ultimately reach the equilibrium state with the lowest energy.However,in biological systems,there are numerous highenergy states far from equilibrium.One typical example is the transmembrane ion-concentration gradient,which plays crucial roles in maintaining homeostasis,regulating cell volume,and enabling cell signaling.Transmembrane ion-concentration gradient is achieved by an active transport process that requires the input of energy and the action of pump proteins.Replicating this process with synthetic supramolecular systems is particularly challenging,requiring both the input of energy and very specific,spatiotemporal control over ion uptake and release.In nature,pump proteins,such as protein-based ion channels,have evolved highly intricate architectures to perform this function.In contrast,Aprahamian and coworkers recently developed a much simpler smallmolecule system that functions as a molecular ion pump,utilizing light energy to pump chloride ions across a hydrophobic barrier against the concentration gradient[1]. 展开更多
关键词 active transport process light powered molecular pump high energy states transmembrane concentration gradient ion concentration gradient maintaining homeostasisregulating equilibrium state chemical processes
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CONCENTRATION AND UNIQUENESS OF MINIMIZERS FOR FRACTIONAL SCHRÖDINGER ENERGY FUNCTIONALS
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作者 Lintao LIU Shuai YAO +1 位作者 Kaimin TENG Haibo CHEN 《Acta Mathematica Scientia》 2025年第5期1981-2009,共29页
We consider a constrained minimization problem arising in the fractional Schrödinger equation with a trapping potential.By exploring some delicate energy estimates and studying decay properties of solution sequen... We consider a constrained minimization problem arising in the fractional Schrödinger equation with a trapping potential.By exploring some delicate energy estimates and studying decay properties of solution sequences,we obtain the concentration behavior of each minimizer of the fractional Schrödinger energy functional when a↗a^(*):=‖Q‖_(2)^(2s),where Q is the unique positive radial solution of (-△)^(s)u+su-|u|2su=0 in R^(2).Based on the discussion of the concentration phenomenon,we prove the local uniqueness of minimizers by establishing a local Poho zaev identity and studying the blow-up estimates to the nonlocal operator(-△)^(s). 展开更多
关键词 concentration energy estimates asymptotic uniqueness Pohozaev identity
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Application of holographic laser scanning to determine the electron concentration in the plasma forming the apokamp
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作者 Anastasiia KOZHEVNIKOVA Igor ALEKSEENKO +1 位作者 Viktor TARASENKO Dmitry SCHITZ 《Plasma Science and Technology》 2025年第4期74-80,共7页
Streamer discharges that do not transition to a spark channel are now being widely investigated.One of these discharges is the apokamp discharge,in which streamers start from a diffuse spark channel having a curved sh... Streamer discharges that do not transition to a spark channel are now being widely investigated.One of these discharges is the apokamp discharge,in which streamers start from a diffuse spark channel having a curved shape at a high repetition rate of voltage pulse.In this work,to estimate the electron concentration in the plasma forming the apokamp a digital holographic laser scanning method is applied for the first time.The method is based on a comparison of the phases of two optical wavefronts,registered at different time instants in the form of digital holograms.The result of the phase comparison between the wavefronts is presented in the form of a numerically calculated map of the phase difference of the reconstructed wavefronts.A gas-discharge plasma is a phase(transparent)object,and the interference fringes are formed as a result of the change in the refractive index introduced by the plasma with respect to the original unperturbed medium.The obtained value of the refractive index allows estimation of the concentration of electrons in the spark channel plasma.It is shown that at as the voltage pulse repetition rate increases from 5 to 50 kHz the concentration of electrons in the plasma forming the apokamp decreases by an estimated four times. 展开更多
关键词 digital holography plasma diagnostics apokamp spark channel electron concentration
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A high-throughput measurement of critical micelle concentrations based on absolute aggregation-caused quenching probes
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作者 Xin Ji Aun Raza +3 位作者 Jianping Qi Yi Lu Haisheng He Wei Wu 《Journal of Pharmaceutical Analysis》 2025年第3期651-653,共3页
Amphiphiles,including surfactants,have emerged as indispensable elements in materials science and pharmaceutical science,and their functions are highly relying on the critical micelle concentration(CMC)[1,2].Numerous ... Amphiphiles,including surfactants,have emerged as indispensable elements in materials science and pharmaceutical science,and their functions are highly relying on the critical micelle concentration(CMC)[1,2].Numerous fluorimetry-based probes have been developed to measure CMCs[3](Fig.S1).However,CMC measurements using these probes suffer from a time-consuming and laborious procedure and large uncertainties,primarily due to their poor photo-stabilities and highly fluctuating fluorescence backgrounds. 展开更多
关键词 high throughput measurement photo stabilities fluorescence backgrounds critical micelle concentration cmc numerous materials science critical micelle concentration fluorimetry based probes absolute aggregation caused quenching
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Delayed covering causes the accumulation of motile sperm, leading to overestimation of sperm concentration and motility with a Makler counting chamber
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作者 Lin Yu Qing-Yuan Cheng +4 位作者 Ye-Lin Jia Yan Zheng Ting-Ting Yang Ying-Bi Wu Fu-Ping Li 《Asian Journal of Andrology》 2025年第1期59-64,共6页
According to the World Health Organization(WHO)manual,sperm concentration should be measured using an improved Neubauer hemocytometer,while sperm motility should be measured by manual assessment.However,in China,thous... According to the World Health Organization(WHO)manual,sperm concentration should be measured using an improved Neubauer hemocytometer,while sperm motility should be measured by manual assessment.However,in China,thousands of laboratories do not use the improved Neubauer hemocytometer or method;instead,the Makler counting chamber is one of the most widely used chambers.To study sources of error that could impact the measurement of the apparent concentration and motility of sperm using the Makler counting chamber and to verify its accuracy for clinical application,67 semen samples from patients attending the Department of Andrology,West China Second University Hospital,Sichuan University(Chengdu,China)between 13 September 2023 and 27 September 2023,were included.Compared with applying the cover glass immediately,delaying the application of the cover glass for 5 s,10 s,and 30 s resulted in average increases in the sperm concentration of 30.3%,74.1%,and 107.5%,respectively(all P<0.0001)and in the progressive motility(PR)of 17.7%,30.8%,and 39.6%,respectively(all P<0.0001).However,when the semen specimens were fixed with formaldehyde,a delay in the application of the cover glass for 5 s,10 s,and 30 s resulted in an average increase in the sperm concentration of 6.7%,10.8%,and 14.6%,respectively,compared with immediate application of the cover glass.The accumulation of motile sperm due to delays in the application of the cover glass is a significant source of error with the Makler counting chamber and should be avoided. 展开更多
关键词 concentration improved Neubauer hemocytometer Makler counting chamber MOTILITY SPERM
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High-voltage poly(ethylene oxide)all-solid-state lithium batteries enabled by high-concentration interfacial layer
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作者 Hao-Tong Li Geng-Chen Wang +3 位作者 Zi-Hu Kang Yue Zheng Ning-Ning Wu Xia Tao 《Rare Metals》 2025年第10期7136-7146,共11页
Poly(ethylene oxide)(PEO)solid electrolytes hold great promise in all-solid-state lithium batteries(ASSLBs)with high-energy and safety capabilities.However,the PEO electrolyte is hardly resistant to degrade electroche... Poly(ethylene oxide)(PEO)solid electrolytes hold great promise in all-solid-state lithium batteries(ASSLBs)with high-energy and safety capabilities.However,the PEO electrolyte is hardly resistant to degrade electrochemically at high voltages(>4 V)in ASSLBs.Herein,we design and prepare a highly efficient and stable PEO-based solid electrolyte(denoted as PEO-L/DTPEO)applied to high-voltage ASSLBs,in which the Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)-containing PEO(PEO-L)serves as a bulk of the electrolyte and the PEO with dualsalts(LiDFOB and high-concentration LiTFSI)forms an ultrathin coating layer(DT-PEO)covering on PEO-L.With 3%coating layer,the PEO-L/DT-PEO electrolyte exhibits an enhanced decomposition potential(>4.9 V vs.Li/Li^(+))originating from the high concentration of LiTFSI as well as renders Al foil current collector high anticorrosion by the introduction of LiDFOB.Upon coupling with highvoltage NCM811 cathode,the DT-PEO efficiently suppresses the interfacial degradation kinetics between electrolyte and cathode,and slows down the irreversible phase change of NCM811.The assembled PEO-L/DT-PEObased Li/NCM811 battery exhibits an excellent cycling stability of remaining 63.0%after 400 cycles at a cutoff voltage of 4.2 V as well as an initial discharge specific capacity of 164.5 mAh g^(-1)at a rate of 0.4C.This work offers a facile and feasible strategy to overcoming interface decomposition of the PEO electrolyte matching perfectly with high-voltage cathode for high-performance ASSLBs. 展开更多
关键词 All-solid-state battery High-voltage cathode High concentration Dual-salts Interface stability
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The transformation of nor-seco-cucurbit[10]uril to cucurbit[5]uril and cucurbit[8]uril controlled by its own concentration
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作者 Shaojie Deng Peihua Ma +1 位作者 Qinghong Bai Xin Xiao 《Chinese Chemical Letters》 2025年第2期345-349,共5页
Nor-seco-cucurbit[10]uril(ns-CB[10])is a kinetic product with unique structure.The single bridged methylene in its structure makes the molecular cavity of ns-CB[10]more deformable when compared to ordinary cucurbit[n]... Nor-seco-cucurbit[10]uril(ns-CB[10])is a kinetic product with unique structure.The single bridged methylene in its structure makes the molecular cavity of ns-CB[10]more deformable when compared to ordinary cucurbit[n]uril,reducing its structural stability.Repeated experiments showed that ns-CB[10]gradually cracks in an acidic solution and changes the specificity of cucurbit[5]uril(CB[5])and cucurbit[8]uril(CB[8])under more robust acidic solutions and when heated.A series of experiments were designed to study the transformation behavior of ns-CB[10].It was found that the concentration of ns-CB[10]was correlated with the content distribution of CB[5]and CB[8].This study explores the influencing factors and mechanisms of the transformation of ns-CB[10]to CB[5]and CB[8].The results are of great significance for the application of ns-CB[10],understanding the formation mechanism of cucurbit[n]urils.Furthermore,it provides a new pathway for synthesizing new cucurbit[n]urils. 展开更多
关键词 uril Cracking Transformation concentration control Mechanism
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Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent
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作者 H.HOSSEINI O.BALILASHAKI 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期139-156,共18页
The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically.It is assu... The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically.It is assumed that the source is located outside the cavity at a specified distance from the borehole axis.The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed.Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid,empty borehole,and rigid inclusion with a hard boundary is employed for the analysis.Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions,the proposed boundary conditions at the interface are satisfied.Stresses are formulated by means of wave potential functions in a three-dimensional(3D)manner.The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra.Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis.To give an overall outline of the study,a numerical example is presented.The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values.In addition,the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole.Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases,and good agreement is achieved. 展开更多
关键词 point source cylindrical cavity porous medium wave-field transformation stress concentration
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