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Improvement of dispersive soil properties by enzyme-induced carbonate precipitation technology:Mechanical,microstructural,and statistical analysis
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作者 Zechuang Li Yue Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1633-1652,共20页
A novel method that combines reinforced enzyme-induced carbonate precipitation(REICP)was proposed to improve the mechanical properties of dispersive soil.Dispersive soils,which are highly susceptible to erosion caused... A novel method that combines reinforced enzyme-induced carbonate precipitation(REICP)was proposed to improve the mechanical properties of dispersive soil.Dispersive soils,which are highly susceptible to erosion caused by rainfall or seepage,pose significantenvironmental challenges.It is essential to focus on modifying dispersive soil using environmentally friendly methods.This study investigated the cohesion,internal friction angle,permeability,hydrostability test,and microstructure of dispersive soil treated with enzyme-induced carbonate precipitation(EICP)-MgCl2-xanthan gum(REICP),using statistical analysis.A series of laboratory experiments was conducted,including direct shear tests,permeability experiments,mud ball tests,simulated rainfall tests,Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),and scanning electron microscopy(SEM).The results showed that the combined treatment significantly enhanced the mechanical properties of dispersive soil.At the optimal ratio,cohesion increased by a factor of 2,and the permeability coefficientdecreased by approximately 1.7×10^(7)times.Additionally,the strength parameters gradually increased with curing time.Microstructural analyses indicated that calcite precipitation,pore filling,and ionic redistribution significantlyimproved the mechanical properties and hydrostability of the soil.Statistical analyses showed that EICP materials and xanthan gum increased soil cohesion,while magnesium chloride enhanced the internal friction angle and reduced porosity.This study integrates mechanical testing,statistical analysis,and microstructural evaluation to propose a sustainable and environmentally friendly method for improving dispersive soils.This approach reduces the use of chemical modifiers,minimizes environmental impacts,and demonstrates application potential in the stabilization of dispersive soils. 展开更多
关键词 dispersive soil REINFORCEMENT Shear strength Permeability Hydrostability
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Atomically Dispersed Pt-Ru Dual-Atom Catalysts for Efficient Low-Temperature CO Oxidation Reaction
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作者 Yanan Qi Hongqiu Chen +12 位作者 Feng Hong Xiangbin Cai Zhehan Ying Jiangyong Diao Zhimin Jia Jiawei Chen Ning Wang Shengling Xiang Xiaowen Chen Guodong Wen Bo Sun Geng Sun Hongyang Liu 《Nano-Micro Letters》 2026年第5期816-830,共15页
Single-atom catalysts(SACs)have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency,distinctive geometric,and electronic configurations.However,the effica... Single-atom catalysts(SACs)have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency,distinctive geometric,and electronic configurations.However,the efficacy of SACs remains limited for certain reactions requiring simultaneous activation of multiple reactants over metallic active sites.Herein,we report an atomically dispersed Pt1Ru1 dual-atom pair site anchored on nanodiamond@graphene(ND@G)for CO oxidation.The Pt1Ru1 dual-atom catalyst shows an exceptional turnover frequency(TOF)of 17.6.10^(-2)s^(-1)at significantly lower temperature(30℃),achieving a tenfold increase in TOF compared to singleatom Pt1/ND@G catalyst(1.5.10^(-2)s^(-1))and surpassing to previously reported Pt-based catalysts under similar conditions.Moreover,the catalyst demonstrates excellent stability,maintaining its activity for 40 h at 80℃without significant deactivation.The superior catalytic performance of Pt-Ru dual-atom catalysts is attributed to the synergistic effect between Pt and Ru atoms with enhanced metallicity for improving simultaneous adsorption and activation of CO and O_(2),and the tuning of conventional competitive reactant adsorption into a non-competitive pathway over dual-atom pair sites.The present work manifests the advantages of dual-atom pair sites in heterogeneous catalysis and paves the way for precise design of catalysts at the atomic scale. 展开更多
关键词 CO oxidation Atomically dispersed Dual-atom catalysts Pt-Ru Synergistic effect
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Solid dispersion of BIBR1532:A potent therapeutic for oesophageal squamous cancer
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作者 Xue-Juan Zhang Nai-Xuan Deng +4 位作者 Huan-Qing Zhang Jie-Zuan Cen Zi-Xuan Zheng Meng-Qin Guo Zheng-Wei Huang 《World Journal of Gastrointestinal Oncology》 2026年第1期291-295,共5页
This letter addresses challenges in the clinical translation of BIBR1532,a promising telomerase inhibitor,for the treatment of esophageal squamous cell carcinoma(ESCC).BIBR1532 exerts its anti-cancer effect by activat... This letter addresses challenges in the clinical translation of BIBR1532,a promising telomerase inhibitor,for the treatment of esophageal squamous cell carcinoma(ESCC).BIBR1532 exerts its anti-cancer effect by activating DNA damage response(ATR/CHK1 and ATM/CHK2)pathways and downregulating telomere-binding proteins.Although its therapeutic potential is limited by poor aqueous solubility,solid dispersion(SD)technology may overcome this obstacle.Systematic analysis using PubChem-derived simplified molecular input line entry system identifiers and artificial intelligence-driven FormulationDT platform evaluation(oral formulation feasibility index:0.38)revealed that the SD technology,with superior scalability(32 approved products by 2021)and lower production risks,outperforms lipid-based formulations as an optimal dissolution strategy.Material analysis revealed hydroxypropyl methylcellulose(HPMC)as the optimal carrier with lower hygroscopicity,higher temperature and no intestinal targeting,thus enabling ESCC therapy.HPMC-based SD enhances BIBR1532 solubility and bioavailability for effective ESCC treatment.Future studies should focus on pilot tests for SD fabrication. 展开更多
关键词 BIBR1532 SOLUBILITY Solid dispersion Oesophageal squamous cancer Hydroxypropyl methylcellulose Druggability
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Processing map for oxide dispersion strengthening Cu alloys based on experimental results and machine learning modelling
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作者 Le Zong Lingxin Li +8 位作者 Lantian Zhang Xuecheng Jin Yong Zhang Wenfeng Yang Pengfei Liu Bin Gan Liujie Xu Yuanshen Qi Wenwen Sun 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期292-305,共14页
Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening pa... Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%. 展开更多
关键词 oxide dispersion strengthened Cu alloys constitutive model machine learning hot deformation processing maps
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Dispersive liquid-liquid microextraction combined with capillary electrophoresis for simultaneous determination of five fluoroquinolone antibiotics in marine crude drugs,seawater,and seafood samples
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作者 Yingying LOU Guangli ZHAO +6 位作者 Jingyi YAN Dani SUN Jinmao YOU Huiquan XIAO Huitao LIU Guisheng LI Jinhua LI 《Journal of Oceanology and Limnology》 2026年第1期137-149,共13页
To simultaneously enrich,separate,and determine five fluoroquinolone antibiotics(FQs)in marine crude drugs(MCDs),seawater and seafood,we conducted this study using vortex assisted dispersed liquid-liquid microextracti... To simultaneously enrich,separate,and determine five fluoroquinolone antibiotics(FQs)in marine crude drugs(MCDs),seawater and seafood,we conducted this study using vortex assisted dispersed liquid-liquid microextraction(DLLME),followed by capillary electrophoresis(CE)-UV.A single-variable optimization was employed to examine the factors influencing the separation effect of CE and the extraction efficiency of DLLME,including buffer solution,organic solvent,separation voltage,extractant,dispersant,and sample solution pH.Under the optimal conditions,the baseline separation of the five FQs was achieved within 6 min.The analytical performance of the method was assessed using six types of actual samples,including three MCDs of hippocampus,clam,and kelp,seawater,and two seafood of prawn and pomfret,demonstrating good linearity ranging from 0.1-5 or 0.01-5μg/mL.The limits of detection(LODs)and limits of quantification(LOQs)for the five FQs in MCDs were 0.0022-0.0292 and 0.0066-0.0973μg/mL,respectively.The LODs and LOQs in seawater and seafood were 0.0009-0.0262 and 0.0029-0.0874μg/mL,respectively.The matrix effects of this method were evaluated in the hippocampus,seawater,and prawn,and the results show that DLLME could effectively eliminate matrix interference.Satisfactory recovery rates were achieved in all the six tested actual samples.This developed DLLME-CE method was proven simple to operate,accurate and reliable,with high sensitivity,making it suitable for the analysis of multiple antibiotic residues in complex matrices. 展开更多
关键词 fluoroquinolone antibiotic(FQ) dispersive liquid-liquid microextraction(DLLME) capillary electrophoresis(CE) marine crude drug(MCD) SEAFOOD seawater
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Natal and breeding dispersal patterns in a patchy population of the western yellow wagtail
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作者 Dmitry Shitikov Nikita Grachev +4 位作者 Viktoria Grudinskaya Alexander Grabovsky Stanislav Samsonov Alexey Korolev Tatiana Makarova 《Current Zoology》 2025年第4期535-543,共9页
Dispersal is an important life history trait with signifcant consequences for spatially structured populations,as the exchange of individuals between habitat patches is crucial for maintaining metapopulation connectiv... Dispersal is an important life history trait with signifcant consequences for spatially structured populations,as the exchange of individuals between habitat patches is crucial for maintaining metapopulation connectivity.In this study,we used a long-term data set(2005–2023)to describe dispersal patterns in a patchy population of the Western Yellow Wagtail Motacilla fava within a large(approximately 1,300 km2)study area in the boreal zone of European Russia.We quantifed dispersal distances for birds that dispersed outside their natal or breeding habitat patches and applied a multistate capture–recapture approach to estimate natal and breeding dispersal probabilities.Of 395 adult wagtails and 1,610 nestlings ringed,3%of birds ringed as adults and 3%of birds ringed as nestlings were resighted outside their natal or breeding patches.The probability of natal dispersal(0.29±0.05)was signifcantly higher than the probability of breeding dispersal(0.05±0.01).The median natal dispersal distances(2.8 km for males,3.9 km for females)were the same as the median breeding dispersal distances(2.7 km for males,3.9 km for females).We did not fnd a signifcant effect of the fedging date on either the natal dispersal distance or the natal dispersal probability.Similarly,we did not fnd a signifcant effect of the previous reproductive success on either the breeding dispersal distance or the breeding dispersal probability.Our results indicate that strong breeding site fdelity and short-distance natal dispersal are the dominant dispersal strategies in a patchy population of the western yellow wagtail. 展开更多
关键词 breeding dispersal dispersal probability natal dispersal patchy population western yellow wagtail
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Search for Dispersed Repeats in Oryza sativa Genome Using Iterative Procedure Method
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作者 Valentina RUDENKO Eugene KOROTKOV 《Rice science》 2025年第4期472-474,共3页
In this study,we searched for dispersed repeats(DRs)in the rice(Oryza sativa)genome using the iterative procedure(IP)method.The results revealed that the O.sativa genome contained 79 DR families,comprising 992739 DNA ... In this study,we searched for dispersed repeats(DRs)in the rice(Oryza sativa)genome using the iterative procedure(IP)method.The results revealed that the O.sativa genome contained 79 DR families,comprising 992739 DNA repeats,of which 496762 and 495977 were identified on the forward and reverse DNA strands,respectively.The detected DRs were,on average,374 bp in length and occupied 66.4%of the O.sativa genome.Totally 61%of DRs,identified by the IP method,overlapped with previously annotated dispersed repeats(ADRs)detected using the Extensive De Novo TE Annotator(EDTA)pipeline. 展开更多
关键词 Oryza sativa genome dna repeatsof iterative procedure annotated dispersed repeats dispersed repeats drs de novo TE annotator dispersed repeats
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Effects of urease on strongly alkaline sodium-based dispersive soils from check dams under acidic conditions
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作者 Guanzhou Ren Minqiang Meng +4 位作者 Henghui Fan Yuan Gao Yuyang Ji Shuai Pang Xingyao Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期7397-7409,共13页
This study explores the adaptation of microbial enzymatic techniques,which were originally developed to eliminate amino impurities in alcoholic beverages,for stabilizing strongly alkaline sodium-based dispersive soils... This study explores the adaptation of microbial enzymatic techniques,which were originally developed to eliminate amino impurities in alcoholic beverages,for stabilizing strongly alkaline sodium-based dispersive soils from check dams.Employing acid urease from Lactobacillus reuteri(L.reuteri)and a control group using soybean-derived urease,this research aimed to modify soil alkalinity through biomineralization.Ultraviolet(UV)mutagenesis optimized L.reuteri strains for biomass and activity.Solution experiments were conducted to assess the effects of pH,temperature,and storage duration on urease activity and to evaluate the calcium carbonate production and crystal morphology of the two ureases under varying calcium ion concentrations.Dispersivity identificationtests and tensile strength evaluations were conducted to analyze the disparities in the modifieddispersive soil treated with the two types of ureases.The results showed that soybean urease should be stored under low-temperature conditions and a neutral pH,whereas acid urease from L.reuteri can be stored at room temperature across a range of pH levels.Both urease treatments effectively reduced soil dispersivity and improved tensile strength significantly(up to 94%and 177%,respectively),with acid urease from L.reuteri resulting in superior soil strengthening and ammonia regulation.These findingssuggest that treating alkaline dispersive soils with acid urease is an efficientand eco-friendly method. 展开更多
关键词 Acidic conditions UREASE Lactobacillus reuteri(L.reuteri) dispersive soil dispersIVITY STRENGTH
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Dispersion-engineered subwavelength grating microring resonator for high-sensitivity and wide-range on-chip sensing
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作者 SHIBO SUN XINZHE XIONG +3 位作者 MEIYU CHANG YAMENG XU MEI KONG LI SHEN 《Photonics Research》 2025年第12期3362-3373,共12页
Silicon-based microring resonator sensors are promising components for lab-on-chip sensing systems.However,developing a microring resonator sensor with both high sensitivity and wide detectable range has remained chal... Silicon-based microring resonator sensors are promising components for lab-on-chip sensing systems.However,developing a microring resonator sensor with both high sensitivity and wide detectable range has remained challenging.Here,we experimentally demonstrate a high-sensitivity and wide-range subwavelength grating microring resonator sensor by leveraging its dispersion properties. 展开更多
关键词 microring resonator sensors dispersion engineered high sensitivity subwavelength grating dispersion properties wide range microring resonator chip sensing
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Inverse design of broadband and dispersion-flattened highly GeO2-doped optical fibers based on neural networks and particle swarm algorithm
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作者 LI Runrui WANG Chuncan 《Optoelectronics Letters》 2025年第6期328-335,共8页
Reverse design of highly GeO2-doped silica optical fibers with broadband and flat dispersion profiles is proposed using a neural network(NN) combined with a particle swarm optimization(PSO) algorithm.Firstly,the NN mo... Reverse design of highly GeO2-doped silica optical fibers with broadband and flat dispersion profiles is proposed using a neural network(NN) combined with a particle swarm optimization(PSO) algorithm.Firstly,the NN model designed to predict optical fiber dispersion is trained with an appropriate choice of hyperparameters,achieving a root mean square error(RMSE) of 9.47×10-7on the test dataset,with a determination coefficient(R2) of 0.999.Secondly,the NN is combined with the PSO algorithm for the inverse design of dispersion-flattened optical fibers.To expand the search space and avoid particles becoming trapped in local optimal solutions,the PSO algorithm incorporates adaptive inertia weight updating and a simulated annealing algorithm.Finally,by using a suitable fitness function,the designed fibers exhibit flat group velocity dispersion(GVD) profiles at 1 400—2 400 nm,where the GVD fluctuations and minimum absolute GVD values are below 18 ps·nm-1·km-1and 7 ps·nm-1·km-1,respectively. 展开更多
关键词 neural network predict optical fiber dispersion inverse design neural network nn dispersion flattening inverse desig BROADBAND particle swarm optimization pso
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Generalized(2+1)-Dimensional Sharma-Tasso-Olver-Burgers Equation:Dispersionless Decompositions and Twisted Solitons
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作者 Hui-Ling Wu Sen-Yue Lou 《Chinese Physics Letters》 2025年第9期14-17,共4页
We presents a generalized(2+1)-dimensional Sharma-Tasso-Olver-Burgers(STOB)equation,unifying dissipative and dispersive wave dynamics.By introducing an auxiliary potential𝑦as a new space variable and employing... We presents a generalized(2+1)-dimensional Sharma-Tasso-Olver-Burgers(STOB)equation,unifying dissipative and dispersive wave dynamics.By introducing an auxiliary potential𝑦as a new space variable and employing a simpler deformation algorithm,we deform the(1+1)-dimensional STOB model to higher dimensions.The resulting equation is proven Lax-integrable via introducing strong and weak Lax pairs.Traveling wave solutions of the(2+1)-dimensional STOB equation are derived through an ordinary differential equation reduction,with implicit solutions obtained for a special case.Crucially,we demonstrate that the system admits dispersionless decompositions into two types:Case 1 yields non-traveling twisted kink and bell solitons,while Case 2 involves complex implicit functions governed by cubic-algebraic constraints.Numerical visualizations reveal novel anisotropic soliton structures,and the decomposition methodology is shown to generalize broadly to other higher dimensional dispersionless decomposition solvable integrable systems. 展开更多
关键词 dispersionless decompositions twisted solitons generalized dimensional auxiliary potential strong weak lax pairstraveling wave solutions ordinary differential equation re dissipative dispersive wave dynamicsby lax integrable
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Atomically dispersed Ru on flower-like In_(2)O_(3) to boost CO_(2) hydrogenation to methanol 被引量:1
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作者 Mengyao Xu Fei Liu +4 位作者 Shike Liu Jun Ma Mengqin Yao Xiaodan Wang Jianxin Cao 《Journal of Materials Science & Technology》 2025年第18期289-301,共13页
Metal-based catalysts are prevalent in the CO_(2) hydrogenation to methanol owing to their remarkable catalytic activity.Herein,Ru/In_(2)O_(3) catalysts with different morphologies obtained by doping Ru into In_(2)O_(... Metal-based catalysts are prevalent in the CO_(2) hydrogenation to methanol owing to their remarkable catalytic activity.Herein,Ru/In_(2)O_(3) catalysts with different morphologies obtained by doping Ru into In_(2)O_(3) with irregular,rod-like,and flower-like morphologies are used for catalytic CO_(2) hydrogenation to methanol.Results indicate that the flower-like Ru/In_(2)O_(3)(Ru/In_(2)O_(3)-F)exhibits higher catalytic performance than Ru/In_(2)O_(3) with other morphologies,achieving a 12.9%CO_(2) conversion,74.02%methanol selectivity,and 671.36 mg_(MeOH) h^(−1) g_(cat)^(−1) methanol spatiotemporal yield.Furthermore,Ru/In_(2)O_(3)-F maintains its catalytic stability over 200 h at 5 MPa and 290℃.The promotional effect mainly stems from the fact that electronic structure of Ru can be effectively adjusted by modulating the morphology of In_(2)O_(3).The strong interaction between atomically dispersed Ru and In_(2)O_(3)-F enhances the structural stability of Ru,inhibiting the agglomeration of the catalyst during the reaction process.Furthermore,density-functional theory calculations reveal that highly dispersed Ru atoms not only perform efficient and rapid electronic gain and loss processes,facilitating the catalytic activation of H_(2) into H intermediates.It also enables the generated reactive H to rapidly overflow to the surrounding In sites to participate in CO_(2) reduction.These findings provide a theoretical basis for the development of high-performance catalysts for CO_(2) hydrogenation. 展开更多
关键词 CO_(2)hydrogenation METHANOL Morphology Atomic dispersion RUTHENIUM
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Source apportionment of PM_(2.5) using dispersion normalized positive matrix factorization(DN-PMF)in Beijing and Baoding,China 被引量:1
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作者 Ilhan Ryoo Taeyeon Kim +6 位作者 Jiwon Ryu Yeonseung Cheong Kwang-joo Moon Kwon-ho Jeon Philip K.Hopke Seung-Muk Yi Jieun Park 《Journal of Environmental Sciences》 2025年第9期395-408,共14页
Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were freque... Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were frequently observed during the heating season.Dispersion Normalized Positive Matrix Factorization was applied for the source apportionment of PM_(2.5) as minimize the dilution effects of meteorology and better reflect the source strengths in these two cities.Secondary nitrate had the highest contribution for Beijing(37.3%),and residential heating/biomass burning was the largest for Baoding(27.1%).Secondary nitrate,mobile,biomass burning,district heating,oil combustion,aged sea salt sources showed significant differences between the heating and non-heating seasons in Beijing for same period(2019.01.10–2019.08.22)(Mann-Whitney Rank Sum Test P<0.05).In case of Baoding,soil,residential heating/biomass burning,incinerator,coal combustion,oil combustion sources showed significant differences.The results of Pearson correlation analysis for the common sources between the two cities showed that long-range transported sources and some sources with seasonal patterns such as oil combustion and soil had high correlation coefficients.Conditional Bivariate Probability Function(CBPF)was used to identify the inflow directions for the sources,and joint-PSCF(Potential Source Contribution Function)was performed to determine the common potential source areas for sources affecting both cities.These models facilitated a more precise verification of city-specific influences on PM_(2.5) sources.The results of this study will aid in prioritizing air pollution mitigation strategies during the heating season and strengthening air quality management to reduce the impact of downwind neighboring cities. 展开更多
关键词 Source apportionment dispersion normalized positive matrix factorization Adjacent cities Inter-city impact Source location Heating season Air quality management
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High-Temperature Stable Dispersed Particle Gel for Enhanced Profile Control in Carbon Capture,Utilization,and Storage(CCUS)Applications 被引量:1
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作者 Lin Du Yao-Yu Xiao +2 位作者 Zhi-Chao Jiang Hongbo Zeng Huazhou Li 《Engineering》 2025年第5期128-140,共13页
CO_(2)-responsive gels,which swell upon contact with CO_(2),are widely used for profile control to plug high-permeability gas flow channels in carbon capture,utilization,and storage(CCUS)applications in oil reser-voir... CO_(2)-responsive gels,which swell upon contact with CO_(2),are widely used for profile control to plug high-permeability gas flow channels in carbon capture,utilization,and storage(CCUS)applications in oil reser-voirs.However,the use of these gels in high-temperature CCUS applications is limited due to their rever-sible swelling behavior at elevated temperatures.In this study,a novel dispersed particle gel(DPG)suspension is developed for high-temperature profile control in CCUS applications.First,we synthesize a double-network hydrogel consisting of a crosslinked polyacrylamide(PAAm)network and a crosslinked sodium alginate(SA)network.The hydrogel is then sheared in water to form a pre-prepared DPG suspen-sion.To enhance its performance,the gel particles are modified by introducing potassium methylsilan-etriolate(PMS)upon CO_(2) exposure.Comparing the particle size distributions of the modified and pre-prepared DPG suspension reveals a significant swelling of gel particles,over twice their original size.Moreover,subjecting the new DPG suspension to a 100℃ environment for 24 h demonstrates that its gel particle sizes do not decrease,confirming irreversible swelling,which is a significant advantage over the traditional CO_(2)-responsive gels.Thermogravimetric analysis further indicates improved thermal sta-bility compared to the pre-prepared DPG particles.Core flooding experiments show that the new DPG suspension achieves a high plugging efficiency of 95.3%in plugging an ultra-high permeability sandpack,whereas the pre-prepared DPG suspension achieves only 82.8%.With its high swelling ratio,irreversible swelling at high temperatures,enhanced thermal stability,and superior plugging performance,the newly developed DPG suspension in this work presents a highly promising solution for profile control in high-temperature CCUS applications. 展开更多
关键词 Carbon capture utilization and storage Profile control dispersed particle gel Double-network hydrogel Irreversible swelling
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Hominin and human dispersals in palaeolithic East Asia
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作者 Robin DENNELL 《人类学学报》 北大核心 2025年第1期132-164,共33页
Dispersals,colonisation,immigration and population assimilation or replacement are fundamental themes in the Palaeolithic record of East Asia.Some of these issues can be studied within a biogeographic framework that e... Dispersals,colonisation,immigration and population assimilation or replacement are fundamental themes in the Palaeolithic record of East Asia.Some of these issues can be studied within a biogeographic framework that explains why and how the distribution of hominin species changed over time and space in response to climatic and environmental change.Because hominins(and especially humans)can change their behaviour through technical,social and cognitive developments,biogeographic models also have to incorporate this factor when investigating dispersals.This is particularly important with the dispersals in East Asia by Homo sapiens into rainforests,across open sea to off-shore islands,to the Arctic and the highest parts of the Tibetan Plateau.This paper suggests how hominin and human dispersals in East Asia might be investigated by using a biogeographic framework that can incorporate changes in hominin adaptability and behaviour. 展开更多
关键词 HOMININ HUMAN dispersal East Asia biogeographic
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A review of the dispersion of graphene in cementitious composites and its mechanisms for improving mechanical properties and durability
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作者 KONG Xiang-qing BAN Tian-yi +3 位作者 ZHANG Xiao-meng QIAO Wan-fu HOU Bo JIA Dong-zhou 《新型炭材料(中英文)》 北大核心 2025年第6期1219-1245,共27页
Graphene and its derivatives are two-dimensional nanomaterials with exceptional physical and chemical properties.Research has shown that their addition can counter the inherent deficiencies of cementbased composites,i... Graphene and its derivatives are two-dimensional nanomaterials with exceptional physical and chemical properties.Research has shown that their addition can counter the inherent deficiencies of cementbased composites,including low tensile strength,poor toughness,and high susceptibility to cracking.However,because of its high specific surface area and the van der Waals force between layers,graphene is prone to agglomerate in the cement matrix which can make the properties worse.Hence,improving the graphene dispersion is essential.The surface structure and properties of graphene and its derivatives are first introduced,and the different methods for their dispersion in cement-based materials are reviewed.Their effects on the mechanical properties and durability of cement-based materials are then summarized.Based on these results,the microscopic and nanoscopic mechanisms of the way graphene and its derivatives affect cement-based materials are elaborated.Current problems and future trends in this research area are then considered. 展开更多
关键词 Graphene and its derivatives dispersION Cement-based materials Mechanical strength DURABILITY
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Flatness detection method of splicing detector based on channel spectral dispersion
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作者 ZHAO Hong-chao ZHANG Xiao-qian AN Qi-chang 《中国光学(中英文)》 北大核心 2025年第4期889-898,共10页
For segmented detectors,surface flatness is critical as it directly influences both energy resolution and image clarity.Additionally,the limited adjustment range of the segmented detectors necessitates precise benchma... For segmented detectors,surface flatness is critical as it directly influences both energy resolution and image clarity.Additionally,the limited adjustment range of the segmented detectors necessitates precise benchmark construction.This paper proposes an architecture for detecting detector flatness based on channel spectral dispersion.By measuring the dispersion fringes for coplanar adjustment,the final adjustment residual is improved to better than 300 nm.This result validates the feasibility of the proposed technology and provides significant technical support for the development of next-generation large-aperture sky survey equipment. 展开更多
关键词 large aperture telescope segmented detector surface wavefront detection channel spectral dispersion
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Positive role of regulator in desulfurization of chalcopyrite in seawater based on chelation and dispersion
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作者 SONG Ning-bo YIN Wan-zhong +1 位作者 GONG Xiu-feng YAO Jin 《Journal of Central South University》 2025年第5期1791-1801,共11页
The chemical composition of seawater affects the desulfurization of chalcopyrite in flotation.In this study,desulfurization experiments of chalcopyrite were conducted in both deionized(DI)water and seawater.The result... The chemical composition of seawater affects the desulfurization of chalcopyrite in flotation.In this study,desulfurization experiments of chalcopyrite were conducted in both deionized(DI)water and seawater.The results showed that,the copper grade of the concentrate obtained from seawater flotation decreased to 24.30%,compared to 24.60%in DI water.Concurrently,the recovery of chalcopyrite decreased from 51.39%to 38.67%,while the selectivity index(SI)also had a reduction from 2.006 to 1.798.The incorporation of ethylene diamine tetraacetic acid(EDTA),sodium silicate(SS),and sodium hexametaphosphate(SHMP)yielded an enhancement in the SI value,elevating it from 1.798 to 1.897,2.250 and 2.153,separately.It is particularly noteworthy that an excess of EDTA resulted in a SI value of merely 1.831.The mechanism of action was elucidated through analysis of surface charge measurements,X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FT-IR),extended Derjaguin-Landau Verwey-Overbeek(E-DLVO)theory,and density functional theory(DFT)calculations. 展开更多
关键词 CHALCOPYRITE DESULFURIZATION CHELATION dispersION E-DLVO theory
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Spatial,social,and environmental factors infuencing nataldispersal in the colonial griffon vulture
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作者 Felix Martinez Martina Carrete Guillermo Blanco 《Current Zoology》 2025年第2期170-183,共14页
Natal dispersal is a critical trait for individual ftness and the viability,structure,and genetic identity of populations.However,there is a pronounced information gap for large and long-lived species due to the diffc... Natal dispersal is a critical trait for individual ftness and the viability,structure,and genetic identity of populations.However,there is a pronounced information gap for large and long-lived species due to the diffculty of monitoring individuals at appropriate spatio-temporal scales.Here we study how individual traits and social and environmental characteristics infuence natal dispersal decisions of griffon vultures(Gypsfulvus)using long-term(30 years)monitoring of a large number of individuals marked as nestlings in Spain.Our results show a strong philopatryin both sexes,with some individuals recruiting as breeders on the same cliffs,and even the same nests,where they were born.This philopatrictendency was modulated by the effect of conspecifc density on individual parameters and emphasized the importance of conspecifc attraction and changes in food availability that may have infuenced the increment in colony size and the colonization of new areas.Although furtherresearch is needed considering smaller colonies and more isolated population nuclei,our results highlight the importance of long-term studieson long-lived species to understand the factors that determine their population dynamics and their relationship with anthropogenic activities,whose effects should be predicted and managed using conservation criteria. 展开更多
关键词 Gyps fulvus mad-cow crisis natal dispersal PHILOPATRY recruitment VULTURES
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Strain-manipulated dispersion characteristics of magnonic crystals with Dzyaloshinskii–Moriya interaction and applications on spin-wave devices
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作者 Chuhan Zhou Xiaotian Jiao +3 位作者 Jiaxi Xu Zhaonian Jin Lin Chen Zhikuo Tao 《Chinese Physics B》 2025年第2期431-436,共6页
Dispersion characteristics of magnonic crystals have attracted considerable attention because of the potential applications for spin-wave devices.In this work,we investigated the strain-manipulated dispersion characte... Dispersion characteristics of magnonic crystals have attracted considerable attention because of the potential applications for spin-wave devices.In this work,we investigated the strain-manipulated dispersion characteristics of magnonic crystals with Dzyaloshinskii–Moriya interaction(DMI)and discussed the potential applications in spin-wave devices.Here,the ground states and stabilities of the magnonic crystals were investigated.Then,the strain-manipulated dispersion characteristics of the magnonic crystals based on domains and skyrmions were studied.The simulation results indicated that,the applied strain could manipulate the band widths and the positions of the allowed frequency bands.Finally,the realization of magnonic crystal heterojunctions and potential applications in spin-wave devices,such as filters,diodes,and transistors based on strain-manipulated magnonic crystals were proposed.Our research provides a theoretical foundation for designing tunable spin-wave devices based on strain-manipulated magnonic crystals with DMI. 展开更多
关键词 magnonic crystal spin wave dispersion relation SKYRMION DOMAIN
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