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Determination of well stability and sand risk minimization parameters for gas condensate field conditions using geomechanical and CT-based approaches
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作者 Valerii Khimulia Yury Kovalenko +1 位作者 Vladimir Karev Svyatoslav Barkov 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1570-1586,共17页
The paper presents the results of geomechanical and CT-based studies of deformation,fracture and filtration processes in reservoir rocks of the Arctic shelf gas condensate field.The experimental study combines(i)deter... The paper presents the results of geomechanical and CT-based studies of deformation,fracture and filtration processes in reservoir rocks of the Arctic shelf gas condensate field.The experimental study combines(i)determination of mechanical properties,(ii)true triaxial physical modeling of near-wellbore filtration and geomechanical processes,(iii)triaxial sand production studies,and(iv)digital CT-analysis of the rock matrix and sand particles.Based on true triaxial physical modeling,the relationships between permeability,rock deformation,and stresses around a horizontal well during drawdown were determined.Hollow cylinder-type tests were used to determine the stress conditions for sand release initiation,the intensity of sand production under varying stress states,and the total volume of sand produced.Digital particle size analysis of the matrix and released sand provided insights into the dominant mechanisms of hole failure during sand production.A significant strength anisotropy of reservoir rocks was identified,suggesting that drawdown in horizontal wells could lead to asymmetric bottomhole zone fracture,initiated at the upper and lower points on the wellbore contour.The obtained results allowed to determine(i)the drawdowns required to maintain wellbore stability in the given reservoir interval;(ii)the optimal parameters of downhole gravel filter screens for sand control;(iii)to identify the prevailing type of wellbore fracture and to localize failure initiation points on the wellbore walls.The results highlight the importance of integrating modern laboratory core analysis methods to enhance the development of complex reservoirs and reduce the risks of fractures and sand production in weakly cemented formations. 展开更多
关键词 True triaxial testing Near-wellbore geomechanical processes Stress-strain state Well stability Digital core analysis Grain size distribution Sand production Sand control
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Major-and Trace-Element Chemistry of Clinopyroxene and Amphibole from High-Mg Diorite in Chelyabinsk Massif(Urals):Insights into Petrogenesis and Magma Source Constraints
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作者 Tatiana Osipova Gennadiy Kallistov +1 位作者 Maria Chervyakovskaya Vasiliy Chervyakovskiy 《Journal of Earth Science》 2025年第2期508-523,共16页
Field-and petrographic investigations,together with microanalytical major-and traceelement studies,were carried out on clinopyroxene and amphibole from high-Mg diorite in the subduction-related Chelyabinsk granitic ma... Field-and petrographic investigations,together with microanalytical major-and traceelement studies,were carried out on clinopyroxene and amphibole from high-Mg diorite in the subduction-related Chelyabinsk granitic massif to understand its petrogenesis and source.The clinopyroxene composition(high Mg#,Cr-content,sum of REE and Ti/Eu ratio;depletion in HREE;negative Eu-anomaly)indicates that it formed from a reduced melt derived from a mantle source metasomatized by fluids/melts having crustal affinity.Melt compositions in equilibrium with clinopyroxene and amphibole were calculated using solid/liquid partition coefficients.The high Nb/Y and Zr/Y ratio values of a liquid simulated from clinopyroxene,which appears to have very similar characteristics to sanukitoid melts,indicate a low degree of melting of the mantle source.Melt simulated from amphibole is more evolved and more felsic(dacitic).It displays a geochemical“amphibole fractionation”signature,indicating the peritectic transformation of clinopyroxene to amphibole in the lower crust.Rock textures and major element mineral compositions suggest that further amphibole was precipitated directly from the melt in the middle crust.The results show that the Chelyabinsk highMg diorite was probably formed as a cumulate from sanukitoid-like melt during its ascent and cooling below dacitic liquidus inside the amphibole stability field. 展开更多
关键词 high-Mg diorite CLINOPYROXENE amphibole trace elements cumulus mineral SANUKITOID URALS geochemistry
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The Role of Exosomes as a Key Factor of Cytostatic Resistance in Cancer:Mechanisms of Action,Potential Biomarkers,and Possible Exosome-Based Therapies
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作者 Sandra Kałużna Monika Świerczewska +3 位作者 Sylwia Ciesiółka Małgorzata Partyka Michał Nowicki Karolina Wojtowicz 《Oncology Research》 2026年第1期23-56,共34页
The last research focuses on the role of exosomes in cancer treatment.Exosomes are extracellular vesicles.They can be secreted by cancer cells,and they can modulate chemotherapy sensitivity.Determining exosomal conten... The last research focuses on the role of exosomes in cancer treatment.Exosomes are extracellular vesicles.They can be secreted by cancer cells,and they can modulate chemotherapy sensitivity.Determining exosomal content opens the possibility for guiding treatment strategies for cancer diseases.Exosomal microRNA are considered one of the prime candidates for exosomal biomarkers.Exosomal circular RNAs represent excellent biomarkers for liquid biopsy because of their stability in many types of cancer.Exosomal proteins remain reliable biomarkers also.Exosomes have emerged as promising therapeutic candidates.Their biological properties render them ideal vectors for drug delivery.Genetic modification of exosomes is an effective way to deliver material capable of modulating cellular pathways involved in drug resistance.Furthermore,exosomes have been explored as carriers for metal-chelating agents.Integrating exosome-based therapies with traditional anticancer agents aims to exploit the natural targeting abilities of exosomes to enhance drug delivery.Despite the dynamic development of this field,many mechanisms of exosome action remain incompletely understood.Therefore,it is necessary to conduct further studies that will allow for a better understanding of their role in the process of resistance and will enable the development of effective therapeutic strategies. 展开更多
关键词 EXOSOMES drug resistance CANCER
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Experimental and simulation study of geochemical processes during interaction of carbonated formation water with terrigenous and carbonate rocks
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作者 Chulpan Aidarovna Garifullina Ilya Mikhailovich Indrupskiy +4 位作者 Dmitry S.Klimov Ildar Ilyasovich Ibragimov Azat Abuzarovich Lutfullin Bulat Flusovich Zakiev Fanil Muktasimovich Akhmetzyanov 《Petroleum Science》 2025年第12期4954-4974,共21页
The paper addresses the issues of reducing the concentration of greenhouse gases in the atmosphere through carbon dioxide sequestration by injection to geological formations to enhance oil recovery and underground sto... The paper addresses the issues of reducing the concentration of greenhouse gases in the atmosphere through carbon dioxide sequestration by injection to geological formations to enhance oil recovery and underground storage.Geochemical reactions occurring in a reservoir during CO_(2) injection can affect physical properties of the formation and mechanisms of carbon dioxide capture.The interactions in the“CO_(2)-formation water-rock”system are complex and depends on many factors:mineralogical composition of rock,composition and salinity of formation water,reservoir thermobaric conditions,time.The paper includes a brief review of carbon dioxide interaction studies with formation fluids and reservoir rock minerals.A methodology is presented for studying geochemical processes during interaction of carbon dioxide-saturated formation water with reservoir rock samples.Experimental results for oil-saturated and water-saturated,carbonate and terrigenous reservoir intervals are discussed.The experiments demonstrate complex interactions of CO_(2) with water and rocks under natural conditions.Important aspects are the influence of mineralogical composition on dissolution and secondary precipitation processes as well as changes in aqueous phase composition and pH.Hydrogeochemical modeling workflow for the studied processes is proposed with calibration to experimental data and their appropriate translation to reservoir conditions.The results demonstrate the need for detailed geochemical studies to better assess the effects of CO_(2) on reservoir properties and the risks associated with mineral deposition and dissolution during carbon capture and storage(CCS/CCUS)operations. 展开更多
关键词 Carbon dioxide sequestration CO_(2)EOR CO_(2)geological storage Geochemical processes Mineral dissolution and precipitation Geochemical modeling
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In situ Generation of Carbazole-triazine Thermally Activated Delayed Fluoresscence Emitters within the Conjugated Polymer Chain
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作者 Alexander M.Mitroshin Serguei A.Miltsov +9 位作者 Ilya E.Kolesnikov Dmitriy A.Lypenko Artem V.Dmitriev Larisa S.Litvinova Vladislav M.Korshunov Ilya V.Taydakov Elena V.Ushakova Anastasia V.Rogova Felix N.Tomilin Alexander V.Yakimansky 《Chinese Journal of Polymer Science》 2026年第2期361-370,I0009,共11页
The development of polymeric materials that exhibit blue thermally activated delayed fluorescence(TADF)is of great interest for optoelectronic applications.However,achieving TADF in polymers often requires an elaborat... The development of polymeric materials that exhibit blue thermally activated delayed fluorescence(TADF)is of great interest for optoelectronic applications.However,achieving TADF in polymers often requires an elaborate monomer design.The high-energy local triplet state(^(3)LE)of carbazole complicates its application despite the molecular orbital arrangement being suitable for blue emission.Here,we present an approach to polymer design that makes it possible to solve this problem.We demonstrate the in situ formation of a TADF donor-acceptor system during Suzuki polycondensation,creating an extended carbazole-based donor matrix coupled with a triazine acceptor.The resulting polymer exhibited efficient TADF with a low energy gap(ΔE_(ST))value if a phenyl N-substituent,enabling essential electron delocalization,was present in the carbazole moiety.This work establishes a versatile platform for developing carbazole-based TADF polymers,overcoming the fundamental limitations that hinder their widespread application. 展开更多
关键词 Thermally activated delayed fluorescence(TADF) POLYCARBAZOLE Suzuki polycondensation Photoluminescence
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Validity and Systematic Position of Rana altaica(Rana:Ranidae):Results of a Phylogenetic Analysis 被引量:6
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作者 杨军校 周炜帏 +3 位作者 饶定齐 POYARKOV A.Nikolay KUZMIN Sergius L 车静 《Zoological Research》 CAS CSCD 北大核心 2010年第4期353-360,共8页
In order to evaluate the phylogenetic position and validity of Rana altaica,we investigated the phylogeny of brown frogs in Eurasia by Bayesian Inference and Maximum Parsimony analyses of a fragment from the mitochond... In order to evaluate the phylogenetic position and validity of Rana altaica,we investigated the phylogeny of brown frogs in Eurasia by Bayesian Inference and Maximum Parsimony analyses of a fragment from the mitochondrial DNA gene Cytochrome b.Both analyses resolved R.altaica as nesting deeply within R.arvalis.Most samples of the nominal R.altaica from the Altai region and specimens from Central Siberia shared a haplotype with R.arvalis based on the network analysis.The matrilineal relationships suggested that R.altaica should be considered as a junior synonym of R.arvalis.Furthermore,our study suggested that the species group division of Chinese brown frogs should be re-evaluated within a phylogenetic context. 展开更多
关键词 Rana altaica Rana arvalis Rana arvalis altaica Cytochrome b Demographic expansion
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Real-time automation and monitoring of the batch growth of microalga Tetraselmis viridis and cyanobacterium Limnospira platensis
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作者 Svetlana Yu.Gorbunova Anna L.Avsiyan 《Systems Microbiology and Biomanufacturing》 2025年第2期795-804,共10页
An automated system for the real-time measurement and control of the optical density of the microalga Tetraselmis viridis and cyanobacterium Limnospira platensis has been developed based on the open-source Arduino Nan... An automated system for the real-time measurement and control of the optical density of the microalga Tetraselmis viridis and cyanobacterium Limnospira platensis has been developed based on the open-source Arduino Nano electronics platform.The system consists of a main unit,an optical density sensor,a relay unit,a temperature sensor,and associated software.The optical density sensor consists of light diodes(with a maximum emission spectrum in the infrared region at 940 nm)as a light source and photodiodes as receivers;the culture density is estimated based on the attenuation of radiation passing through it.The proposed method exhibited high accuracy(R2=0.995,with root mean square error being approximately 0.1 g L^(−1))in a wide range of biomass concentrations,from 0.27 to 0.97 g L^(−1) for T.viridis and from 0.035 to 1.25 g L^(−1) for L.platensis.The registered biomass productivity at the linear stage of batch cultivation reached 0.15 g L^(−1) day^(−1) for T.viridis and 0.17 g L^(−1) day−1 for L.platensis.The sensor readings were found to be dependent on air temperature,with a coefficient of 0.0136 V/℃.This suggests that the system has the potential for use in a changing outdoor environment,provided that temperature correction is applied during calculations.Furthermore,the measuring system does not require sampling from the photobioreactor or dilution of high cell concentrations prior to measuring dense microalgae cultures.This eliminates the risk of dilution error and contamination.The experimental application of the system for the studied species demonstrated its potential for use with microalgae species exhibiting diverse pigment compositions,including those prone to sedimentation and filamentous forms. 展开更多
关键词 AUTOMATIZATION Optical density sensor Microalgae TETRASELMIS Limnospira Arduino nano
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Spatial and temporal variations in parameters at the upper boundary of gas hydrate stability zone of the Sea of Okhotsk
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作者 Renat Shakirov Vladimir Luchin +2 位作者 Evgeniya Petrova Neng-you Wu Yi-zhao Wan 《China Geology》 2025年第4期754-764,共11页
This study was used oceanographic database in the Sea of Okhotsk between the period from 1929 to 2020(131286 stations).The paper used gas hydrate dissociation parameters for the“pure methane-seawater”system obtained... This study was used oceanographic database in the Sea of Okhotsk between the period from 1929 to 2020(131286 stations).The paper used gas hydrate dissociation parameters for the“pure methane-seawater”system obtained in the study by Dickens GR and Quinby-Hunt MS.The results have elucidated the spatiotemporal variability of distribution of such parameters at the upper boundary of the gas hydrate stability zone(GHSZ)as water temperature,salinity,and top depth of the stability zone.As the study has shown(based on average long-term spatial distributions),the minimum temperature and depth values of the GHSZ upper boundary in the Sea of Okhotsk occur off the western and southwestern parts of the water area.The maximum temperature and depth values of the GHSZ upper boundary are typical of the southeastern sea area and over the Kamchatka Peninsula slope.This study has also identified an area,where there are no thermobaric conditions for the emergence and stable existence of methane hydrates in the water column.The results presented agree well with the materials of observations conducted during expeditions and the previous data of predictive simulations for the Sea of Okhotsk. 展开更多
关键词 Methane hydrates Thermobaric conditions Stability zone Upper boundary Water column Spatiotemporal variability Sea of Okhotsk
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Membrane Fouling Prediction and Control Using AI and Machine Learning: A Comprehensive Review
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作者 Doaa Salim Musallam Samhan Al-Kathiri Gaddala Babu Rao +5 位作者 Noor Mohammed Said Qahoor Saikat Banerjee Naladi Ram Babu Gadidamalla Kavitha Nageswara Rao Lakkimsetty Rakesh Namdeti 《Journal of Environmental & Earth Sciences》 2025年第6期315-350,共36页
Membrane fouling is a persistent challenge in membrane-based technologies,significantly impacting efficiency,operational costs,and system lifespan in applications like water treatment,desalination,and industrial proce... Membrane fouling is a persistent challenge in membrane-based technologies,significantly impacting efficiency,operational costs,and system lifespan in applications like water treatment,desalination,and industrial processing.Foul-ing,caused by the accumulation of particulates,organic compounds,and microorganisms,leads to reduced permeability,increased energy demands,and frequent maintenance.Traditional fouling control approaches,relying on empirical models and reactive strategies,often fail to address these issues efficiently.In this context,artificial intelligence(AI)and machine learning(ML)have emerged as innovative tools offering predictive and proactive solutions for fouling man-agement.By utilizing historical and real-time data,AI/ML techniques such as artificial neural networks,support vector machines,and ensemble models enable accurate prediction of fouling onset,identification of fouling mechanisms,and optimization of control measures.This review provides a detailed examination of the integration of AI/ML in membrane fouling prediction and mitigation,discussing advanced algorithms,the role of sensor-based monitoring,and the importance of robust datasets in enhancing predictive accuracy.Case studies highlighting successful AI/ML applications across various membrane processes are presented,demonstrating their transformative potential in improving system performance.Emerging trends,such as hybrid modeling and IoT-enabled smart systems,are explored,alongside a criti-cal analysis of research gaps and opportunities.This review emphasizes AI/ML as a cornerstone for sustainable,cost-effective membrane operations. 展开更多
关键词 Membrane Fouling Artificial Intelligence(AI) Machine Learning(ML) Fouling Prediction Smart Membrane Systems
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Comparative efficacy of cementless bipolar hemiarthroplasty and proximal femoral nail anti-rotation in unstable intertrochanteric fractures:A meta-analysis
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作者 Ahmed Mohamed Yousif Mohamed Monzir Salih +10 位作者 Mugahid Mohamed Ayman E Abbas Maysara Elsiddig Moaz Osama Omar Mazin Abdelsalam Basil Elhag Nujud Mohamed Souzan Hassan Eisa Ahmed Samah Ahmed Duaa Mohamed Deena Omar 《World Journal of Orthopedics》 2025年第7期134-145,共12页
BACKGROUND Unstable intertrochanteric fractures in elderly patients require effective surgical management,with both cementless bipolar hemiarthroplasty(CBHA)and proximal femoral nail anti-rotation(PFNA)being valid tre... BACKGROUND Unstable intertrochanteric fractures in elderly patients require effective surgical management,with both cementless bipolar hemiarthroplasty(CBHA)and proximal femoral nail anti-rotation(PFNA)being valid treatment options to reduce morbidity and mortality.AIM To evaluate and compare the outcomes of CBHA and PFNA in treatment of unstable intertrochanteric fractures.METHODS A comprehensive search was conducted to identify relevant studies discussing the outcomes of using both CBH and PFNA in treatment of unstable intertrochanteric fractures.Studies published up to January 1,2025 were searched across multiple databases,including PubMed,EMBASE,Scopus,Web of Science,Cochrane Library,and Google Scholar.Full texts of the selected articles were retrieved,reviewed,and independently assessed by the investigators.Discrepancies were resolved by consensus,with any remaining disagreements being arbitrated by a third author.RESULTS This meta-analysis included three studies,all of which were retrospective,involving a total of 240 patients.The follow-up period for participants was at least 12 months.CBHA was associated with significantly higher blood loss compared to PFNA[mean differences(MD):129.14,95%CI(52.51,205.77),P=0.001],though heterogeneity was high(I²=97%).Operative time showed no significant difference initially[MD:6.10,95%CI(-13.34,25.54),P=0.54],but after excluding one study,BHA had longer operative times[MD:21.51,95%CI(18.60,24.41),P<0.00001].Hospital stay and Harris scores showed no significant differences between groups.CBHA facilitated faster progression to weight-bearing[MD:-11.92,95%CI(-22.46,-1.39),P=0.03]and a lower incidence of prosthetic loosening[risk ratio:0.21,95%CI(0.05,0.92),P=0.04].Refracture and thrombus formation rates were comparable between the two groups.CONCLUSION CBHA offers shorter weight-bearing duration and reduced prosthetic loosening but incurs greater blood loss and longer operative times compared to PFNA.Both techniques show comparable functional recovery,hospital stay,refracture,and thrombus risks.Clinical choice should prioritize early mobilization or surgical minimalism,guided by patient needs.Further prospective studies are warranted. 展开更多
关键词 Cementless bipolar hemiarthroplasty Proximal femoral nail anti-rotation Unstable intertrochanteric fractures META-ANALYSIS Unstable Functional outcomes FFNA
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Electrochemical behavior and effective extraction of erbium in fused LiCl-KCl eutectic
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作者 Henan Zhang Wantong Li +6 位作者 Jing Yu Qi Liu Alena Novoselova Valeri Smolenski Yongde Yan Milin Zhang Jun Wang 《Journal of Rare Earths》 2025年第7期1513-1522,共10页
For the efficient electrolytic extraction of Er from spent nuclear fuel,a series of electrochemical methods was used to research the electrochemical behavior of Er(Ⅲ)in the LiCl—KCl system on inert(Mo)electrode and ... For the efficient electrolytic extraction of Er from spent nuclear fuel,a series of electrochemical methods was used to research the electrochemical behavior of Er(Ⅲ)in the LiCl—KCl system on inert(Mo)electrode and on reactive(Ni)electrodes.On the inert Mo electrode,the reduction of Er(Ⅲ)to Er(0)is a onestep with three-electron and quasi-reversible reaction process.Meanwhile,the apparent generation Gibbs free energy and activity coefficients of Er(Ⅲ)on the inert electrode were determined.Thereafter,the electrochemical reduction of Er(Ⅲ)on the Ni electrode was emphatically investigated.Er(Ⅲ)is reduced at a corrected potential owing to the formation of Ni-Er alloys.In addition,thermodynamic parameters such as partial excess Gibbs free energy change of Er in Ni,activity and apparent generation Gibbs free energy of the Ni-Er alloys were determined by the electromotive force method.Finally,different Ni-Er alloys were produced using potentiostatic electrolysis on the Ni cathode by controlling different potentials,Moreover,electrolytic extraction was carried out on the Ni cathode at the potential of-2.0 V,and the separation efficiency of Er reaches 99.72%,which proves the practicability of separating Er from LiCl-KCl eutectic on the reactive Ni cathode. 展开更多
关键词 Electrochemical reduction process Reactive Ni electrode Ni-Er intermetallic compounds Thermodynamic properties Electrochemical separation Rare earths
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Numerical and experimental characterization of nail penetration induced thermal runaway propagation in 21,700 lithium-ion batteries:Exploring the role of interstitial thermal barrier materials
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作者 Zeyu Sun Elliott Read +3 位作者 Yongxiu Chen Yuhang Dai James Marco Paul R.Shearing 《Journal of Energy Chemistry》 2025年第10期576-589,共14页
Thermal runaway(TR)in lithium-ion batteries(LIBs)involves a complicated multiphysics process with potentially catastrophic consequences,highlighting the importance of investigating effective prevention strategies.This... Thermal runaway(TR)in lithium-ion batteries(LIBs)involves a complicated multiphysics process with potentially catastrophic consequences,highlighting the importance of investigating effective prevention strategies.This study employs a lumped model integrating electrochemical and decomposition reaction kinetics to predict the evolution of the TR of LIBs triggered by axial nail penetration,validated by experimental tests.A computational fluid dynamics(CFD)-based turbulent flow model is further employed to simulate the thermal runaway propagation(TRP)behavior induced by high-temperature gases within the battery module.A parameterized analysis based on numerical simulation is conducted to quantify the impact of thermal insulation material properties on thermal diffusion and heat accumulation within the module.The results indicate that damage to the battery vent significantly increases the risk of sidewall rupture during TR.The incorporation of thermal barriers is essential in the thermal design of battery modules to prevent heat transfer via convection from the thermal exhaust caused by sidewall rupture to adjacent cells.In addition,a reduction in the thermal diffusivity of the thermal barrier material is required to minimize thermal exchange between battery cells.By adopting insulating materials with thermal diffusivity lower than 0.3 mm^(2)/s,the TRP of batteries can be mitigated under non-enclosed conditions.These findings contribute to improved battery safety and inform the development of more effective thermal protection measures and safety standards. 展开更多
关键词 Battery thermal runaway Nail penetration Multiphysics modeling Energy storage systems safety
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Luminescence enhancement effects of Ca_(x)Sr_(2-x)Nb_(2)O_(7):Er^(3+),Tm^(3+) phosphors for temperature sensing and anti-counterfeiting applications
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作者 Wenchao Chen Huabo Gao +5 位作者 Maxim S.Molokeev Qi Chen Xiangpeng Geng Lefu Mei Xin Min Bin Ma 《Journal of Rare Earths》 2025年第7期1345-1354,共10页
Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 n... Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 nm laser excitation,attributed to the^(4)S_(3/2)→^(4)I_(15/2)transition.By increasing the content of Ca^(2+),the crystal field regulation of rare earth ions is realized and the luminescence enhancement is induced,which is manifested by the increase of^(2)H_(11/2),^(4)S_(3/2)→^(4)I_(15/2)emission.Furthermore,the temperature sensing sensitivities of C_(0.6)S_(1.4)N:Er,Tm and C_(0.6)S_(1.4)N:Er,Tm based on non-thermally coupled energy levels were studied.Finally,an anti-counterfeiting imprint was prepared using phosphors,which have high brightness and excellent photothermal stability.This work not only confirms that closer ionic radii substitution enables to increase the electronic density of states,improve the crystal field symmetry and enhance the luminescence,but also provides a promising phosphor system for temperature sensing and anti-counterfeiting applications,opening up new prospects in the optimization of the optical properties of phosphors. 展开更多
关键词 Ca_(x)Sr_(2-x)Nb_(2)O_(7):Er Tm phosphor Luminescence enhancement Crystal field Temperature sensing ANTI-COUNTERFEITING Rare earths
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Detection of Ca^(2+)-dependent acid phosphatase activity identifies neuronal integrity in damaged rat central nervous system after application of bacterial melanin 被引量:1
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作者 Tigran R. Petrosyan Anna S. Ter-Markosyan Anna S. Hovsepyan 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第7期1147-1152,共6页
The study aims to confirm the neuroregenerative effects of bacterial melanin (BM) on central nervous system injury using a special staining method based on the detection of Ca^2+-dependent acid phosphatase activity... The study aims to confirm the neuroregenerative effects of bacterial melanin (BM) on central nervous system injury using a special staining method based on the detection of Ca^2+-dependent acid phosphatase activity. Twenty-four rats were randomly assigned to undergo either unilateral destruction of sensorimotor cortex (group I; n = 12) or unilateral rubrospinal tract transection at the cervical level (C3-4) (group II; n = 12). In each group, six rats were randomly selected after surgery to undergo intramuscular injection of BM solution (BM subgroup) and the remaining six rats were intramuscularly in)ected with saline (saline subgroup). Neurological testing confirmed that BM accelerated the recovery of motor function in rats from both BM and saline subgroups. Two months after surgery, Ca^2+-dependent acid phosphatase activity detection in combination with Chilingarian's calcium adenoside triphosphate method revealed that BM stimulated the sprouting of fibers and dilated the capillaries in the brain and spinal cord. These results suggest that BM can promote the recovery of motor function of rats with central nervous system injury; and detection of Ca^2+-dependent acid phosphatase activity is a fast and easy method used to study the regeneration-promoting effects of BM on the injured central nervous system. 展开更多
关键词 nerve regeneration bacterial melanin histochemical analysis rubrospinal tract sensorimotor cortex Ca^2+-dependent acid phosphatase activity rats neural regeneration
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Distribution and role of fluorine in the aquatic ecosystem(mineral springs,groundwater,tributaries,Baikal water,and the Angara water source)of Lake Baikal,Russia 被引量:1
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作者 Valentina Grebenshchikova Mikhail Kuzmin +1 位作者 Anna Novopashina Elena Kuz’mina 《China Geology》 2025年第2期303-313,共11页
Several conjugate components represent the aquatic ecosystem of Lake Baikal:Baikal water(surface and deep water),groundwater from boreholes,water of numerous Baikal tributaries,cold and hot mineral springs around Lake... Several conjugate components represent the aquatic ecosystem of Lake Baikal:Baikal water(surface and deep water),groundwater from boreholes,water of numerous Baikal tributaries,cold and hot mineral springs around Lake Baikal,and the Angara River,the only runoff reflecting all this aquatic diversity.River waters in the Baikal region are known to be deficient in some vital elements,including fluorine.This article discusses the features of the fluorine distribution in the water from the conjugate components of the Baikal ecosystem.Fluorine ion concentrations in the water of the Baikal ecosystem was determined using the potentiometric method.The study represents the monitoring that was carried out between 1997 and 2022 years.We determine likely causes of high and low fluorine concentrations in the water from different components,propose and substantiate the fluorine sources,geological and geochemical model of its influx and distribution features in the water of the Baikal ecosystem. 展开更多
关键词 Clean fresh water Aquatic ecosystem Concentration FLUORINE Sources Anthropogenic factor Formation model Lake Baikal
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Enhanced Lead and Zinc Removal via Prosopis Cineraria Leaves Powder: A Study on Isotherms and RSM Optimization 被引量:1
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作者 Rakesh Namdeti Gaddala Babu Rao +7 位作者 Nageswara Rao Lakkimsetty Noor Mohammed Said Qahoor Naveen Prasad B.S Uma Reddy Meka Prema.P.M Doaa Salim Musallam Samhan Al-Kathiri Muayad Abdullah Ahmed Qatan Hafidh Ahmed Salim Ba Alawi 《Journal of Environmental & Earth Sciences》 2025年第1期292-305,共14页
This study investigates the potential of Prosopis cineraria Leaves Powder(PCLP)as a biosorbent for removing lead(Pb)and zinc(Zn)from aqueous solutions,optimizing the process using Response Surface Methodology(RSM).Pro... This study investigates the potential of Prosopis cineraria Leaves Powder(PCLP)as a biosorbent for removing lead(Pb)and zinc(Zn)from aqueous solutions,optimizing the process using Response Surface Methodology(RSM).Prosopis cineraria,commonly known as Khejri,is a drought-resistant tree with significant promise in environmental applications.The research employed a Central Composite Design(CCD)to examine the independent and combined effects of key process variables,including initial metal ion concentration,contact time,pH,and PCLP dosage.RSM was used to develop mathematical models that explain the relationship between these factors and the efficiency of metal removal,allowing the determination of optimal operating conditions.The experimental results indicated that the Langmuir isotherm model was the most appropriate for describing the biosorption of both metals,suggesting favorable adsorption characteristics.Additionally,the D-R isotherm confirmed that chemisorption was the primary mechanism involved in the biosorption process.For lead removal,the optimal conditions were found to be 312.23 K temperature,pH 4.72,58.5 mg L-1 initial concentration,and 0.27 g biosorbent dosage,achieving an 83.77%removal efficiency.For zinc,the optimal conditions were 312.4 K,pH 5.86,53.07 mg L-1 initial concentration,and the same biosorbent dosage,resulting in a 75.86%removal efficiency.These findings highlight PCLP’s potential as an effective,eco-friendly biosorbent for sustainable heavy metal removal in water treatment. 展开更多
关键词 Prosopis Cineraria LEAD ZINC Isotherms OPTIMIZATION
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Investigation of the formation processes of CO_(2) hydrate films on the interface of liquid carbon dioxide with humic acids solutions 被引量:1
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作者 Aleksey K.Sagidullin Sergey S.Skiba +1 位作者 Tatyana P.Adamova Andrey Y.Manakov 《Chinese Journal of Chemical Engineering》 2025年第3期53-61,共9页
Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the inte... Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the interface,further growth of hydrate due to the suction of water in the capillary system formed between the wall of the cuvette and the end boundary of the hydrate layer occurs.Most probably,substantial effects on the formation of this capillary system may be caused by variations in reactor wall properties,for example,hydrophobic-hydrophilic balance,roughness,etc.We found,that the rate of CO_(2) hydrate film growth on the surface of the humic acid aqueous solution is 4-fold to lower in comparison with the growth rate on the surface of pure water.We suppose that this is caused by the adsorption of humic acid associates on the surface of hydrate particles and,as a consequence,by the deceleration of the diffusion of dissolved carbon dioxide to the growing hydrate particle. 展开更多
关键词 HYDRATES Carbon dioxide Humic acids solutions Reaction kinetics Liquid liquid reaction Film growth
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Moral distress and intention to leave among intensive care unit nurses in the United Arab Emirates
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作者 Amina M.Ahmad Wegdan Bani-Issa +2 位作者 Fatma Refaat Muna S.Al-Tamimi Taliaa M.Al-Yafeai 《International Journal of Nursing Sciences》 2025年第6期581-587,I0003,共8页
Objectives:The study aimed to examine the severity of moral distress and intention to leave among ICU nurses in the United Arab Emirates(UAE),and explore the influencing factors of intention to leave.Methods:The study... Objectives:The study aimed to examine the severity of moral distress and intention to leave among ICU nurses in the United Arab Emirates(UAE),and explore the influencing factors of intention to leave.Methods:The study utilized a cross-sectional research design.A convenience non-probability sample of 341 nurses from various private and government hospitals across different emirates in the UAE participated in June 2022.Data were collected using a self-administered questionnaire comprising demographic information,the Moral Distress Scale–Revised.Multivariable logistic regression was used to identify factors associated with intention to leave.Results:The study found that a large majority(71.9%)of ICU nurses experienced severe moral distress,and more than 35%had intention to leave.Futile end-of-life interventions emerged as the most distress-provoking aspect of practice[16.0(0,16.0)].Multivariable analysis revealed nurses experiencing severe moral distress had 3.73 times the odds of intending to leave their job compared with those experiencing mild distress(95%CI:1.81,7.69;P<0.001)and being aged 31–40 years(OR=2.02;95%CI:1.23,3.33;P=0.005)was independently associated with a higher intention to leave.Conclusions:Severe moral distress was prevalent among ICU nurses in the UAE and strongly associated with intention to leave,and also those aged 31–40 years.Promoting ethical support,shared decision-making,and nurse empowerment is vital to improving retention and care quality. 展开更多
关键词 Cross-sectional study Intensive care unit Intention to leave Moral distress NURSE
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Features of the Mineral Composition of the Quaternary Sediments of the Development Areas of the Erosion Processes on the Territory of the Tunkinsk’s Depression
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作者 S.I.Shtel’makh L.A.Pavlova T.G.Ryashchenko 《Journal of Geological Resource and Engineering》 2019年第4期113-122,共10页
The article considers the some features of the Quaternary sediments mineral composition of the development areas of the erosion processes on the territory of the Tunkinsk’s depression.Main objectives of our research ... The article considers the some features of the Quaternary sediments mineral composition of the development areas of the erosion processes on the territory of the Tunkinsk’s depression.Main objectives of our research are to determine the entering forms of Na,Mg,Al,Si,P,S,K,Ca,Ti,Cr,Mn,Fe,Zn,Cu,Zr,and Ba in the composition of the investigated sediments.The mineral composition was studied by the method of an electron probe X-ray spectral microanalysis(XRM)using wave spectrometers,and the method of X-ray diffraction analysis.The localization centers of Cr,Cu,Zn,Zr,and Ba were established in the mineral composition of the studied sediments.Maximum content of BaO(14.42 wt%)was detected in alkali K-feldspar in the clay sediments of modern alluvial complex(aQ4).Crystallochemical formulas of different minerals were obtained. 展开更多
关键词 Electron probe X-ray spectral MICROANALYSIS mineral composition QUATERNARY SEDIMENTS FELDSPARS ore MINERALS
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The synergistic antitumor effect of Karanahan technology and in situ vaccination using anti-OX40 antibodies
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作者 VERA RUZANOVA ANASTASIA PROSKURINA +10 位作者 GENRIKH RITTER EVGENIYA DOLGOVA SOFYA OSHIKHMINA SVETLANA KIRIKOVICH EVGENIY LEVITES YAROSLAV EFREMOV OLEG TARANOV ALEXANDR OSTANIN ELENA CHERNYKH NIKOLAY KOLCHANOV SERGEY BOGACHEV 《Oncology Research》 2025年第5期1229-1248,共20页
Objectives:Currently,there exist two approaches to the treatment of malignant neoplasms:the Karanahan technology and in situ vaccination,which are based on chronometric delivery of therapeutic agents to the tumor depe... Objectives:Currently,there exist two approaches to the treatment of malignant neoplasms:the Karanahan technology and in situ vaccination,which are based on chronometric delivery of therapeutic agents to the tumor depending on the characteristics of tumor cells,as well as the immune status.The main purpose of this study was to experimentally prove the feasibility of combining the Karanahan technology and in situ vaccination withαOX40 antibodies into a single therapeutic platform to achieve a potent additive antitumor therapeutic effect.Methods:BALB/c mice grafted with B-cellular lymphoma A20 were treated using the Karanahan technology consisting of intraperitoneal cyclophosphamide administrations and intratumoral DNA injections according to an individually determined therapeutic regimen,together with in situ vaccination withαOX40.A pathomorphological analysis of the organs of experimental animals that died during the initial attempt to combine the two technologies was carried out.An analysis of blood cell populations was performed to determine the safe time for antibody administration:the number of immune cells capable of activating systemic inflammation(CD11b+Ly-6C+,CD11b+Ly-6G+,CD3–NKp46+CD11b+),the presence of Fc receptor and OX40 on the surface of these cells,and the number of neutrophils activated to NETosis were analyzed.Based on the analysis results,the antitumor efficacy of various modes of combining the Karanahan technology and in situ vaccination was studied.Results:WhenαOX40 was administered 5 h after each treatment using the Karanahan technology,mass death of mice caused by systemic inflammation and multiple organ failure was observed.The state of blood cells after the treatment using the Karanahan technology at the time points corresponding to antibody injections was analyzed to elucidate the reasons for this effect.It was found that at some time points,there occurs activation of the immune system and a powerful release(up to 16%)of monocytes and granulocytes carrying Fc receptor and OX40 on their surface into blood;when interacting withαOX40,they can activate the lytic potential of these cells.Activation of neutrophils to NETosis was also observed.Based on these findings,a study was carried out in different time regimes to combine the Karanahan technology andαOX40 injections.WhenαOX40 was injected into the points of minimal release of myeloid cells into the blood,increased survival rate and the greatest antitumor efficacy were observed:37%of animals survived without relapses on day 100 after experiment initiation.Conclusions:The results obtained indicate that it is possible to combine the Karanahan technology and in situ vaccination withαOX40,with obligatory constant monitoring of the number of myeloid cells in peripheral blood to determine the safe time for antibody injection. 展开更多
关键词 Karanahan technology OX40 Antitumor immunity Tumor-initiating stem cells Systemic inflammatory reaction
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