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Controllable synthesis of CuAlO_(2) via solid-phase method and its catalytic performance for methanol steam reforming to hydrogen 被引量:4
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作者 QING Shaojun SUN Xun +3 位作者 LI Xinglong WANG Lei WU Zhiwei WANG Jianguo 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第11期1641-1651,共11页
This study explores the controllable synthesis of CuAlO_(2) using copper hydroxide and pseudo-boehmite powders as raw materials via a simple solid-phase ball milling method,along with its catalytic performance investi... This study explores the controllable synthesis of CuAlO_(2) using copper hydroxide and pseudo-boehmite powders as raw materials via a simple solid-phase ball milling method,along with its catalytic performance investigation in methanol steam reforming(MSR).Various catalysts were prepared under different conditions,such as calcination temperature,calcination atmosphere,and heating rate.Characterization techniques including BET,XRD,XPS,SEM and H2-TPR were employed to analyze the samples.The results revealed significant effects of calcination temperature on the phase compositions,specific surface area,reduction performance,and surface properties of the CA-T catalysts.Based on the findings,a synthesis route of CuAlO_(2) via the solid-phase method was proposed,highlighting the importance of high calcination temperature,nitrogen atmosphere,and low heating rate for CuAlO_(2) formation.Catalytic evaluation data demonstrated that CuAlO_(2) could catalyze MSR without pre-reduction,with the catalytic performance of CA-T catalysts being notably influenced by calcination temperature.Among the prepared catalysts,the CA-1100 catalyst exhibited the highest catalytic activity and stability.The findings of this study might be useful for the further study of the catalytic material for sustained release catalysis,including the synthesis of catalytic materials and the regulation of sustained release catalytic performance. 展开更多
关键词 CuAlO_(2) solid-phase method methanol steam reforming sustained release catalysis calcination temperature
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Seed-mediated solid-phase synthesis of carbon-confined Ni_(3)Ga_(1) intermetallic nanocubes for highly selective hydrogenation
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作者 Yifan Liu Shiqiang Liu +4 位作者 Xiaoxue Wang Shingo Hasegawa Ken Motokura Guangying Fu Yong Yang 《Nano Research》 2026年第1期324-335,共12页
Atomically ordered precious intermetallic nanoparticles have garnered significant attention for diverse applications due to their well-defined surface atomic arrangements and exceptional electronic and geometric prope... Atomically ordered precious intermetallic nanoparticles have garnered significant attention for diverse applications due to their well-defined surface atomic arrangements and exceptional electronic and geometric properties.However,synthesizing non-precious ordered intermetallics that exhibit high stability under operating conditions remains a formidable challenge,primarily owing to their strong oxyphilicity,highly negative reduction potentials,and low corrosion resistance.In this work,we report a facile yet versatile seed-mediated solid-phase approach for fabricating uniform Ni_(3)Ga_(1) intermetallic nanocubes(NCs)fully encapsulated within N-doped carbon layers(denoted as Ni_(3)Ga_(1)@NC-800).Extensive characterization confirms the formation of a unique core-shell architecture,with atomic-resolution structural analysis and X-ray absorption fine structure measurements unequivocally verifying the atomically ordered Ni_(3)Ga_(1) intermetallic phase.The Ni_(3)Ga_(1)@NC-800 catalyst demonstrates exceptional performance in the 1,4-hydrogenation of α,β-unsaturated carbonyl compounds,exhibiting both remarkable activity and exclusive selectivity while maintaining high stability over multiple reaction cycles without observable performance decay.Combined experimental and theoretical calculations reveal that the strong interatomic p-d orbital hybridization facilitates electron transfer from Ga to Ni atoms,resulting in electron localization on ordered Ni atoms.This electronic configuration positively influences H_(2)activation and optimizes substrate adsorption strength,thereby substantially improving catalytic efficiency.Furthermore,this synthetic strategy proves generalizable,successfully extending to the synthesis of other non-precious ordered Ni_(1)Sn_(1) and Ni_(2)In_(3) intermetallics confined within N-doped carbon matrices. 展开更多
关键词 non-precious intermetallics Ni_(3)Ga_(1) solid-phase synthesis selective hydrogenation confined catalyst
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HPLC-UV method with solid-phase extraction for the quantitative determination of biapenem in human plasma and its application in pharmacokinetic study 被引量:1
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作者 朱旭 孙亚欣 +3 位作者 何晓静 邱枫 李岭 肇丽梅 《Journal of Chinese Pharmaceutical Sciences》 CAS 2011年第1期70-76,共7页
Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction (SPE) and HPLC was developed for the quantitativ... Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction (SPE) and HPLC was developed for the quantitative determination of biapenem in human plasma. Stability and feasibility of the method was validated through a series of experiments. Using Vitamin B6 as an internal standard, analyte was separated on a Capcell Pak C18 column after SPE on Oasis hydrophilic-lipophilic balance (HLB) cartridge. The mobile phase was comprised of 0.05 mol/L NaH2PO4 (pH 5.7) and methanol (98:2, v/v) at a flow rate of 1.0 mL/min. Ultraviolet absorbance was measured at 300 nm. The calibration curve was linear in the concentration range of 0.04-50.00 μg/mL, and the lower limit of quantification was as low as 0.04 μg/mL. Recovery rates of biapenem at 0.10, 5.00, and 25.00 μg/mL were about 70%. The validated method has been successfully applied for quantifying biapenem in human samples and a pharmacokinetic study of 12 healthy volunteers who received three different doses (150, 300 and 600 mg) of biapenem by intravenous infusion. Our method has featured good accuracy and precision, and the processed sample was stable. Therefore, it can be propagated for clinical use. 展开更多
关键词 BIAPENEM solid-phase extraction High-performance liquid chromatography Pharmacokinetic study
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Solid-phase extraction of trace Au(Ⅲ) with SDG and determination by the catalytic spectrophotometric method 被引量:2
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作者 LI Huizhi ZHAI Yubo 《Rare Metals》 SCIE EI CAS CSCD 2008年第6期560-565,共6页
The new catalytic kinetic spectrophotometric method for Au(III) determination was developed and validated. It was based on the catalytic effect of gold on the oxidation of sudan red III by ammonium peroxodisulfate ... The new catalytic kinetic spectrophotometric method for Au(III) determination was developed and validated. It was based on the catalytic effect of gold on the oxidation of sudan red III by ammonium peroxodisulfate ((NH4)2S2O8) with nitrilo triacetic acid as an activator in microemulsion and H2SO4 medium. Under optimum conditions, there was the linearity of the calibration curve in the concentration range from 0 to 20 μg/L Au(Ⅲ) at 520 nm. The relative standard deviation was 3.0% with a correlation coefficient of 0.9986. The detection limit achieved was 9.75 × 10^-5 μg/mL. A new method using a column packed with sulfhydryl dextrose gel (SDG) as a solid-phase extractant has been developed for the preconcentration and separation of Au(Ⅲ) ions. The method has been applied to the determination of trace gold with satisfactory results. 展开更多
关键词 analytical chemistry catalytic kinetic spectrophotometric method solid-phase extraction gold(Ⅲ)
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TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes:A novel method for the solid-phase synthesis of dihydrocoumarins and coumarins 被引量:2
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作者 E Tang Wen Li +1 位作者 Zhang Yong Gao Xi Gu 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第6期631-634,共4页
TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes was performed using polystyrene-supported succini- midyl selenide as the selenium source. This catalytic process provides an efficient method for th... TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes was performed using polystyrene-supported succini- midyl selenide as the selenium source. This catalytic process provides an efficient method for the regioselective synthesis of dihydrocoumarins possessing a seleno-functionality, followed by traceless cleavage of selenium linker to provide dihydrocoumar- ins and coumarins in good yields and purifies. 展开更多
关键词 Lewis acid Seleno-arylation Succinimidyl selenide solid-phase synthesis Dihydrocoumarins COUMARINS
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Development of matrix solid-phase dispersion method for the extraction of short-chain chlorinated paraffins in human placenta 被引量:5
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作者 Ying Wang Wei Gao +4 位作者 Jing Wu Huijin Liu Yingjun Wang Yawei Wang Guibin Jiang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第12期154-162,共9页
Chlorinated paraffins(SCCPs) are widely used worldwide, and they can be released into the environment during their production, transport, usage and disposal, which pose potential risks for human health. In this work... Chlorinated paraffins(SCCPs) are widely used worldwide, and they can be released into the environment during their production, transport, usage and disposal, which pose potential risks for human health. In this work, an efficient, reliable and rapid pretreatment method based on matrix solid-phase dispersion(MSPD) was developed for the analysis of short-chain CPs(SCCPs) in human placenta by gas chromatograph-electron capture negative ion low-resolution mass spectrometry(GC-ECNI-LRMS) and gas chromatography–quadrupole time-of-flight mass spectrometry(GC–QTOF-HRMS). The MSPD-relevant parameters including dispersing sorbent,sample-to-sorbent mass ratio, and elution solvent were optimized using the orthogonal test.Silica gel was found to be the optimal dispersing sorbent among the selected matrices. Under the optimal conditions, 44% acidic silica gel can be used as the co-sorbent to remove lipid and eluted by the mixture of hexane and dichloromethane(7:3, V/V). The spiked recoveries of the optimized method were 77.4% and 91.4% for analyzing SCCPs in human placenta by GC-ECNI-LRMS and GC–QTOF-HRMS, and the corresponding relative standard deviations were10.2% and 5.6%, respectively. The method detection limit for the total SCCPs was 36.8 ng/g(dry weight, dw) and 19.2 ng/g(dw) as measured by GC-ECNI-LRMS and GC–QTOF-HRMS,respectively. The concentrations of SCCPs in four human placentas were in the range of 展开更多
关键词 Short-chain chlorinated paraffins Matrix solid-phase dispersion Human placenta
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Multiresidue Method for Determination of 67 Pesticides in Water Samples Using Solid-Phase Extraction with Centrifugation and Gas Chromatography-Mass Spectrometry 被引量:3
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作者 Abir Kouzayha Abdul Rahman Rabaa +3 位作者 Mohamad Al Iskandarani Daniel Beh Hélène Budzinski Farouk Jaber 《American Journal of Analytical Chemistry》 2012年第3期257-265,共9页
A new multi-residue method based on solid-phase extraction (SPE) with centrifugation was developed for determination and quantitation of 67 pesticides in water samples. Two SPE cartridges were tested: Chromabond C18 a... A new multi-residue method based on solid-phase extraction (SPE) with centrifugation was developed for determination and quantitation of 67 pesticides in water samples. Two SPE cartridges were tested: Chromabond C18 and Oasis HLB. Parameters that influence the extraction efficiency such as the eluent volume, the sample loading volume, the addition of organic solvent to water sample, sorbent drying and elute concentration were optimized. The innovation of this work was the examination of the use of a centrifugation technique in both the drying and elution steps. When combined with centrifugation, the volume of the elution solvent was reduced to 2 mL and the time for sorbent drying decreased also to 10 min under vacuum. Under the optimized conditions, this method showed good recoveries higher than 65% - 68% for the 67 analyzed pesticides using the C18 and HLB cartridges with relative standard deviations lower than 9.7% - 12.3%. Limits of quantification were between 2 and 20 ng.L–1. The simplicity of the described method, use of less of organic solvent, short procedure time, and good recoveries demonstrate the advantages of this environmentally friendly approach for routine analysis of numerous samples. 展开更多
关键词 MULTI-RESIDUE PESTICIDES solid-phase Extraction CENTRIFUGATION Gas Chromatography-Mass SPECTROMETRY
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Solid-phase microextraction of endogenous metabolites from intact tissue validated using a Biocrates standard reference method kit 被引量:1
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作者 Runshan Will Jiang Karol Jaroch Janusz Pawliszyn 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第1期55-62,共8页
Improved analytical methods for the metabolomic profiling of tissue samples are constantly needed.Currently,conventional sample preparation methods often involve tissue biopsy and/or homogenization,which disrupts the ... Improved analytical methods for the metabolomic profiling of tissue samples are constantly needed.Currently,conventional sample preparation methods often involve tissue biopsy and/or homogenization,which disrupts the endogenous metabolome.In this study,solid-phase microextraction(SPME)fibers were used to monitor changes in endogenous compounds in homogenized and intact ovine lung tissue.Following SPME,a Biocrates AbsoluteIDQ assay was applied to make a downstream targeted metabolomics analysis and confirm the advantages of in vivo SPME metabolomics.The AbsoluteIDQ kit enabled the targeted analysis of over 100 metabolites via solid-liquid extraction and SPME.Statistical analysis revealed significant differences between conventional liquid extractions from homogenized tissue and SPME results for both homogenized and intact tissue samples.In addition,principal component analysis revealed separated clustering among all the three sample groups,indicating changes in the metabolome due to tissue homogenization and the chosen sample preparation method.Furthermore,clear differences in free metabolites were observed when extractions were performed on the intact and homogenized tissue using identical SPME procedures.Specifically,a direct comparison showed that 47 statistically distinct metabolites were detected between the homogenized and intact lung tissue samples(P<0.05)using mixed-mode SPME fibers.These changes were probably due to the disruptive homogenization of the tissue.This study's findings highlight both the importance of sample preparation in tissue-based metabolomics studies and SPME's unique ability to perform minimally invasive extractions without tissue biopsy or homogenization while providing broad metabolite coverage. 展开更多
关键词 solid-phase microextraction Solvent extraction Metabolomics Sample preparation In vivo sampling
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An optimized numerical method to pre-researching the performance of solid-phase oxygen control in a non-isothermal lead–bismuth eutectic loop 被引量:1
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作者 Xiao-Bo Li Rui-Xian Liang +6 位作者 Yi-Feng Wang Hui-Ping Zhu Fang Liu Yang Liu Cong Li Hao Wu Feng-Lei Niu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第3期77-88,共12页
In the present work,a new transient calculation method for parameters that can be used to evaluate the ability of oxygen control in a non-isothermal lead-bismuth eutectic(LBE)loop with solid-phase oxygen control was p... In the present work,a new transient calculation method for parameters that can be used to evaluate the ability of oxygen control in a non-isothermal lead-bismuth eutectic(LBE)loop with solid-phase oxygen control was proposed.It incorporates the dissolution process of PbO particles and the oxygen mass transfer process,and an optimized method was used for finding out the optimized oxygen mass transfer coefficient.In numerical terms,three mass transfer models were simultaneously applied,and comparisons of calculated and experimental results from the CRAFT loop indicated that the optimized calculation method and these new oxygen mass transfer models were correct and applicable to other LBE loops.Through this calculation method,we aimed to optimize prediction of the distribution of oxygen and iron concentrations,time taken to establish the steady state of oxygen,and maximum dissolution/precipitation rates of corrosion products and corrosion depth across the entire LBE loop.We hope that this work will provide a potential reference for designing a more intelligent oxygen control system in the future. 展开更多
关键词 LBE solid-phase oxygen control Operating domain Operating model Corrosion depth Dissolution/precipitation
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Study on the ion behavior of solid-phase reaction synthesis of iron chromite at 1473 K
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作者 Yan Wang Peiyuan Ni +1 位作者 Yuling Liu Tengfei Deng 《International Journal of Minerals,Metallurgy and Materials》 2025年第5期1103-1113,共11页
The enrichment of chromium in the magnetic iron chromite(Fe(Cr_(x)Fe_(1-x))_(2)O_(4))phase is crucial for the recovery and recycling of chromium in stainless-steel pickling sludge.The kinetics and reaction mechanism o... The enrichment of chromium in the magnetic iron chromite(Fe(Cr_(x)Fe_(1-x))_(2)O_(4))phase is crucial for the recovery and recycling of chromium in stainless-steel pickling sludge.The kinetics and reaction mechanism of the solid-phase reaction between Fe_(3)O_(4)and Cr_(2)O_(3)were investigated using the diffusion couple method at 1473 K.Not only the diffusion behavior of Fe^(2+)ions and Cr^(3+)ions was elucidated,but also the solid solution behavior of Fe^(3+)ions was discussed clearly.The microscopic morphology of the diffusion couple and the change in the concentrations of Fe and Cr cations across the diffusion layers were analyzed using scanning electron microscopy and en-ergy dispersive spectroscopy.The self-diffusion coefficients of cations were calculated based on the concentration profiles of Fe and Cr,with the results indicating that the self-diffusion coefficient of the Fe ions was consistently higher than that of the Cr ions.Additionally,a mixture of Fe_(3)O_(4)and Cr_(2)O_(3)was annealed at 1373-1473 K for 1-5 h,and the kinetic parameters were calculated by studying the phase content of the product.The phase content of Fe(Cr_(x)Fe_(1-x))_(2)O_(4)in the product was determined by Rietveld refinement of X-ray diffraction data,revealing that an activation energy(E)of 177.20 kJ·mol^(-1) and a pre-exponential factor(B)of 610.78 min^(-1)of the solid-phase reac-tion that produced the Fe(Cr_(x)Fe_(1-x))_(2)O_(4)spinel. 展开更多
关键词 diffusion couple solid-phase reaction KINETICS iron chromite
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Grafting Maleic Anhydride onto Carbon Fiber via a Solid-phase Grafting Method
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作者 林国良 郑玉婴 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第9期1458-1464,共7页
By combining the strong and light carbon fibers (CFs) with polymers, composite materials with extraordinary mechanical properties are achieved. However, the mechanical properties of the as-prepared CF-reinforced pol... By combining the strong and light carbon fibers (CFs) with polymers, composite materials with extraordinary mechanical properties are achieved. However, the mechanical properties of the as-prepared CF-reinforced polymer composites can not satisfy the applications in certain fields, especially for the poor interactions between CFs and the polymers. To enhance the mechanical properties of composite materials, a solid phase grafting method has been developed to improve the adhesion forces between CFs and the polymer, by modifying the surfaces of CFs. The effects of the reaction temperature, reaction time, as well as the dosage of the initiator and maleic anhydride (MAH) on the grafting efficiency have been investigated systematically. The structure and the surface chemistry of functionalized CFs have been characterized by Fourier Transform Infrared (FT-IR), Scanning Electron Microscope (SEM), X-ray Photoelectron Spectroscopy (XPS), Thermogravimetric (TG), and contact angle test. All of these results demonstrate that MAH is grafted onto the surface of CFs successfully by the solid phase grafting method. The MAH grafted CFs significantly improve its wettability, which further improves the interfacial adhesion between CFs and the polymeric matrix. The optimal reaction conditions are determined, such as the MAH/CF molar ratio, the dosage of initiator, the reaction temperature and the reaction time to be 3/1, 2%, 90℃ and 4 h, respectively. These attractive interracial characteristics of modified CFs suggest that the method proposed herein is a novel and efficient approach to develop CF-reinforced polymer composites with outstanding mechanical properties for cutting-edge industrial applications. 展开更多
关键词 carbon fiber maleic anhydride fuctionalized solid-phase grafting
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Optimization of the Solid-phase Fermentation Medium of Metarhizium flavoviride by Response Surface Method
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作者 Li Maoye Lin Huafeng +4 位作者 Li Shiguang Pan Jing Xu Amei Chen Dexin Yin Jianli 《Plant Diseases and Pests》 CAS 2015年第1期35-40,共6页
Rice flour, puparium of yellow mealworm, peanut shell and sunflower seed shell are made into the culture medium, and the optimal solid-phase fermen- tation formula for M. flavoviride is figured out. In the solid-phase... Rice flour, puparium of yellow mealworm, peanut shell and sunflower seed shell are made into the culture medium, and the optimal solid-phase fermen- tation formula for M. flavoviride is figured out. In the solid-phase fermentation, Design-Expert is applied to analyze the significance of all components on the sporu- lotion, and response surface method used to optimize the fermentation medium of M. flavoviride. The results show that puparlum of yellow mealworm is the most sig- nificant component for the sporulation; and the optimal medium formula for the fermentation of M. flavoviride: 0.25-g rice flour, 0. 14-g yellow mealworm pupari- urn, 1.00-g peanut shell, and 0.25-g sunflower seedshell. In this optimal medium, the sporulation achieves 100. 013 × 10^8 spores/mL fungal liquid, 31.7% higher than that of the initial design. Application of the optimal formula will reduce the production cost, obtain higher yield of spores, produce no pollution, and offer tech- nical support for the future large-scale production. 展开更多
关键词 Metarhizium flavoviride solid-phase fermentation Response surface
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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Crushing evolution in pebble bed based on a novel method:a crushable DEM study
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作者 Jian Wang Ming‑Zhun Lei +4 位作者 Ming‑Zong Liu Qi‑Gang Wu Zi‑Cong Cai Kai‑Song Wang Hai‑Shun Deng 《Nuclear Science and Techniques》 2026年第1期212-224,共13页
In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical m... In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical model,and its validity was verified using a simple impact test.A crushable discrete element method(DEM)framework is built based on the previously established theoretical model.The tensile strength,which considers the fractal theory,size effect,and Weibull variation,was assigned to each generated particle.The assigned strength is then used for crush detection by comparing it with its maximum tensile stress.Mass conservation is ensured by inserting a series of sub-particles whose total mass was equal to the quality loss.Based on the crushable DEM framework,a numerical simulation of the crushing behavior of a pebble bed with hollow cylindrical geometry under a uniaxial compression test was performed.The results of this investigation showed that the particle withstands the external load by contact and sliding at the beginning of the compression process,and the results confirmed that crushing can be considered an important method of resisting the increasing external load.A relatively regular particle arrangement aids in resisting the load and reduces the occurrence of particle crushing.However,a limit exists to the promotion of resistance.When the strain increases beyond this limit,the distribution of the crushing position tends to be isotropic over the entire pebble bed.The theoretical model and crushable DEM framework provide a new method for exploring the pebble bed in a fusion reactor,considering particle crushing. 展开更多
关键词 Crushing behavior Granular material Discrete element method Pebble bed Fractal theory
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A Deep Reinforcement Learning-Based Partitioning Method for Power System Parallel Restoration
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作者 Changcheng Li Weimeng Chang +1 位作者 Dahai Zhang Jinghan He 《Energy Engineering》 2026年第1期243-264,共22页
Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision... Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision process is formulated as a Markov decision process(MDP)model to maximize the modularity.Corresponding key partitioning constraints on parallel restoration are considered.Second,based on the partitioning objective and constraints,the reward function of the partitioning MDP model is set by adopting a relative deviation normalization scheme to reduce mutual interference between the reward and penalty in the reward function.The soft bonus scaling mechanism is introduced to mitigate overestimation caused by abrupt jumps in the reward.Then,the deep Q network method is applied to solve the partitioning MDP model and generate partitioning schemes.Two experience replay buffers are employed to speed up the training process of the method.Finally,case studies on the IEEE 39-bus test system demonstrate that the proposed method can generate a high-modularity partitioning result that meets all key partitioning constraints,thereby improving the parallelism and reliability of the restoration process.Moreover,simulation results demonstrate that an appropriate discount factor is crucial for ensuring both the convergence speed and the stability of the partitioning training. 展开更多
关键词 Partitioning method parallel restoration deep reinforcement learning experience replay buffer partitioning modularity
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An improved open-top dynamic chambers method for measuring the exchange fluxes of N_(2)O,NO and NH_(3) from farmland
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作者 Minhang Tan Yining Hu +6 位作者 Yifei Song Zixuan Huang Yujing Mu Junfeng Liu Chenglong Zhang Pengfei Liu Yuanyuan Zhang 《Journal of Environmental Sciences》 2026年第1期535-545,共11页
The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environmen... The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environment and con-tribute to global climate change.However,there remain considerable research gaps in the accurate measurement of NCGs emissions from agricultural fields,hindering the development of effective emission reduction strategies.We improved an open-top dynamic chambers(OTDCs)system and evaluated the performance by comparing the measured and given fluxes of the NCGs.The results showed that the measured fluxes of NO,N_(2)O and NH_(3)were 1%,2%and 7%lower than the given fluxes,respectively.For the determination of NH_(3) concentration,we employed a stripping coil-ion chromatograph(SC-IC)analytical technique,which demonstrated an absorption efficiency for atmospheric NH_(3) exceeding 96.1%across sampling durations of 6 to 60 min.In the summer maize season,we utilized the OTDCs system to measure the exchange fluxes of NO,NH_(3),and N_(2)O from the soil in the North China Plain.Substantial emissions of NO,NH_(3) and N_(2)O were recorded following fertilization,with peaks of 107,309,1239 ng N/(m^(2)·s),respectively.Notably,significant NCGs emissions were observed following sus-tained heavy rainfall one month after fertilization,particularly with NH_(3) peak being 4.5 times higher than that observed immediately after fertilization.Our results demonstrate that the OTDCs system accurately reflects the emission characteristics of soil NCGs and meets the requirements for long-term and continuous flux observation. 展开更多
关键词 Open-top dynamic chambers Nitrogen-containing gases Soil emissions North China Plain method evaluation
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Numerical Simulation of the Welding Deformation of Marine Thin Plates Based on a Temperature Gradient-thermal Strain Method
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作者 Lin Wang Yugang Miao +3 位作者 Zhenjian Zhuo Chunxiang Lin Benshun Zhang Duanfeng Han 《哈尔滨工程大学学报(英文版)》 2026年第1期122-135,共14页
Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The t... Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The traditional thermal elastic-plastic finite element method(TEP-FEM)can accurately predict welding deformation.However,its efficiency is low because of the complex nonlinear transient computation,making it difficult to meet the needs of rapid engineering evaluation.To address this challenge,this study proposes an efficient prediction method for welding deformation in marine thin plate butt welds.This method is based on the coupled temperature gradient-thermal strain method(TG-TSM)that integrates inherent strain theory with a shell element finite element model.The proposed method first extracts the distribution pattern and characteristic value of welding-induced inherent strain through TEP-FEM analysis.This strain is then converted into the equivalent thermal load applied to the shell element model for rapid computation.The proposed method-particularly,the gradual temperature gradient-thermal strain method(GTG-TSM)-achieved improved computational efficiency and consistent precision.Furthermore,the proposed method required much less computation time than the traditional TEP-FEM.Thus,this study lays the foundation for future prediction of welding deformation in more complex marine thin plates. 展开更多
关键词 Marine thin plate Welding deformation Numerical simulation Temperature gradient-thermal strain method Shell element
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Precision and trueness of a method for determing antimony content in groundwater using hydride generation-atomic fluorescence spectrometry
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作者 Bing-bing Liu Lin Zhang Ke Li 《Journal of Groundwater Science and Engineering》 2026年第1期49-58,共10页
At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systema... At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systematically and quantitatively evaluated,which limits the effective implementation of environmental monitoring.In response to this key technical gap,this study aimed to establish a standardized method for determining antimony in groundwater using Hydride Generation–Atomic Fluorescence Spectrometry(HG-AFS).Ten laboratories participated in inter-laboratory collaborative tests,and the statistical analysis of the test data was carried out in strict accordance with the technical specifications of GB/T 6379.2—2004 and GB/T 6379.4—2006.The consistency and outliers of the data were tested by Mandel's h and k statistics,the Grubbs test and the Cochran test,and the outliers were removed to optimize the data,thereby significantly improving the reliability and accuracy.Based on the optimized data,parameters such as the repeatability limit(r),reproducibility limit(R),and method bias value(δ)were determined,and the trueness of the method was statistically evaluated.At the same time,precision-function relationships were established,and all results met the requirements.The results show that the lower the antimony content,the lower the repeatability limit(r)and reproducibility limit(R),indicating that the measurement error mainly originates from the detection limit of the method and instrument sensitivity.Therefore,improving the instrument sensitivity and reducing the detection limit are the keys to controlling the analytical error and improving precision.This study provides reliable data support and a solid technical foundation for the establishment and evaluation of standardized methods for the determination of antimony content in groundwater. 展开更多
关键词 Mandel's h and k statistics Grubbs test Cochran test Repeatability limit Reproducibility limit method bias value
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Low temperature solid-phase sintering of sintered metal fibrous media with high specific surface area 被引量:4
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作者 唐彪 汤勇 +3 位作者 周蕤 陆龙生 刘彬 屈修明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1755-1760,共6页
A procedure of low temperature solid-phase sintering(LTSS) was carried out to fabricate sintered metal fibrous media(SMFM) with high specific surface area.Stainless steel fibers which were produced by cutting proc... A procedure of low temperature solid-phase sintering(LTSS) was carried out to fabricate sintered metal fibrous media(SMFM) with high specific surface area.Stainless steel fibers which were produced by cutting process were first plated with a coarse copper coating layer by electroless plating process.A low-temperature sintering process was then completed at about 800 °C for 1 h under the protection of hydrogen atmosphere.The results show that a novel SMFM with complex surface morphology and high specific surface area(0.2 m2/g) can be obtained in this way.The effect of sintering temperature on the surface morphology and specific surface area of SMFM was studied by means of scanning electron microscopy and Brunauer-Emmett-Teller.The damage of micro-structure during the sintering process mainly contributed to the loss of specific surface area of SMFM and the optimal sintering temperature was 800 °C. 展开更多
关键词 sintered metal fibrous media low temperature solid-phase sintering electroless copper plating surface morphology specific surface area
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Solid-phase sintering process and forced convective heat transfer performance of porous-structured micro-channels 被引量:2
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作者 白鹏飞 易子川 +1 位作者 唐彪 周国富 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期900-906,共7页
A solid-phase sintering process for the low-cost fabrication of composite micro-channels was developed. Three kinds of composite micro-channels with metallic porous structures were designed. The sintering process was ... A solid-phase sintering process for the low-cost fabrication of composite micro-channels was developed. Three kinds of composite micro-channels with metallic porous structures were designed. The sintering process was studied and optimized to obtain porous-structured micro-channels with high porosity. The flow resistance and heat transfer performance in the composite micro-channels were investigated. The composite micro-channels show acceptable flow resistance, significant enhancement of heat transfer and dramatic improvement of flow boiling stability, which indicates a promising prospect for the application in forced convective heat transfer. 展开更多
关键词 solid-phase sintering composite micro-channels porous structure flow resistance convective heat transfer
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