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Interfacial modulation of nano Li_(7)La_(3)Zr_(2)O_(12) composite electrolytes prepared by solvent-free method
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作者 Qigao Han Yaqing Guo +9 位作者 Fuhe Wang Xuechun Lou Fengqian Wang Jun Zhong Jinqiao Du Jie Tian Weixin Zhang Shun Tang Shijie Cheng Yuancheng Cao 《Green Energy & Environment》 2025年第3期528-536,共9页
Solid-state batteries(SSBs) with high safety are promising for the energy fields,but the development has long been limited by machinability and interfacial problems.Hence,self-supporting,flexible Nano LLZO CSEs are pr... Solid-state batteries(SSBs) with high safety are promising for the energy fields,but the development has long been limited by machinability and interfacial problems.Hence,self-supporting,flexible Nano LLZO CSEs are prepared with a solvent-free method at 25℃.The 99.8 wt% contents of Nano LLZO particles enable the Nano LLZO CSEs to maintain good thermal stability while exhibiting a wide electrochemical window of 5.0 V and a high Li~+ transfer number of 0.8.The mean modulus reaches 4376 MPa.Benefiting from the interfacial modulation,the Li|Li symmetric batteries based on the Nano LLZO CSEs show benign stability with lithium at the current densities of 0.1 mA cm^(-2),0.2 mA cm^(-2),and 0.5 mA cm^(-2).In addition,the Li|LiFePO_(4)(LFP) SSBs achieve favorable cycling performance:the specific capacity reaches128.1 mAh g^(-1) at 0.5 C rate,with a capacity retention of about 80% after 600 cycles.In the further tests of the LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811) cathodes with higher energy density,the Nano LLZO CSEs also demonstrate good compatibility:the specific capacities of NCM811-based SSBs reach 177.9 mAh g^(-1) at 0.5 C rate,while the capacity retention is over 96% after 150 cycles.Furthermore,the Li|LFP soft-pack SSBs verify the safety characteristics and the potential for application,which have a desirable prospect. 展开更多
关键词 solvent-free method Nano LLZO CSEs Interfacial modulation Cycling performance Safety characteristics
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Synthesis of mordenite by solvent-free method and its application in the dimethyl ether carbonylation reaction 被引量:1
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作者 Yinghui Liu Shaoduo Liu +8 位作者 Xiaosheng Wang Hongjing Wang Ranjia Li Changchun Yu Chunming Xu Yuxiang Liu Zhengqiu Xie Yongqiang Wang Pan Tang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期216-223,共8页
Mordenite with different Si/Al ratios were synthesized by solvent-free method and used for dimethyl ether(DME)carbonylation reaction.The influence of Si/Al ratio in the feedstock on the structure,porosity and acid sit... Mordenite with different Si/Al ratios were synthesized by solvent-free method and used for dimethyl ether(DME)carbonylation reaction.The influence of Si/Al ratio in the feedstock on the structure,porosity and acid sites were systematically investigated.The characterization results showed that with the increase of Si/Al ratio in the feedstock,part of silicon species fail to enter the skeleton and the specific surface area and pore volume of the samples decreased.The amount of weak acid and medium strong acid decreased alongside with the increasing Si/Al ratio,and the amount of strong acid slightly increased.The Al atoms preferentially enter the strong acid sites in the 8 member ring(MR)channel during the crystallization process.The high Si/Al ratio sample had more acid sites located in the 8 MR channel,leading to more active sites for carbonylation reaction and higher catalytic performance.Appropriately increasing the Si/Al ratio was beneficial for the improvement of carbonylation reaction activity over the mordenite(MOR)catalyst. 展开更多
关键词 CARBONYLATION Dimethyl ether solvent-free ZEOLITE Synthesis CATALYSIS
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Catalyst-free and solvent-free method for the synthesis of quinoxalines under microwave irradiation
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作者 Jian Feng Zhou Gui Xia Gong +1 位作者 Kun Bao Shi San Jun Zhi 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第6期672-675,共4页
A facile procedure for the synthesis, of quinoxalines is being reported starting from benzil and 1,2-diaminobenzene. The reactions were carried out catalyst-free, solvent-free and under microwave irradiation condition... A facile procedure for the synthesis, of quinoxalines is being reported starting from benzil and 1,2-diaminobenzene. The reactions were carried out catalyst-free, solvent-free and under microwave irradiation conditions in high yield (84-98%) with short time (3-6 min) and environmental benign, as well as convenient operation. The structures of all the compounds have been confirmed on the basis of their IR, 1H NMR, and/or 13C NMR, mass spectral data. 展开更多
关键词 QUINOXALINE BENZIL 1 2-Diaminobenzene CATALYST-FREE solvent-free Microwave irradiation
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Large scale synthesis of full-color emissive carbon dots from a single carbon source by a solvent-free method 被引量:6
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作者 Hui Ding Xuan-Xuan Zhou +3 位作者 Zi-Hui Zhang Yun-Peng Zhao Ji-Shi Wei Huan-Ming Xiong 《Nano Research》 SCIE EI CSCD 2022年第4期3548-3555,共8页
Full-color emissive carbon dots(CDs)hold a great promise for various applications,especially in light emitting diodes(LEDs).However,the existing synthetic routes for CDs are carried out in solutions,which suffer from ... Full-color emissive carbon dots(CDs)hold a great promise for various applications,especially in light emitting diodes(LEDs).However,the existing synthetic routes for CDs are carried out in solutions,which suffer from low yields,high pressures,various byproducts,large amounts of waste solvents,and complicated photoluminescence(PL)origins.Therefore,it is necessary to explore large scale synthesis of CDs with high quantum yield(QY)across the entire visible range from a single carbon source by a solvent-free method.In this work,a series of CDs with tunable PL emission from 442 to 621 nm,QY of 23%-56%,and production yield within 34%-72%,are obtained by heating o-phenylenediamine with the catalysis of KCl.Detailed characterizations identify that,the differences between these CDs with respect to the graphitization degree,graphitic nitrogen content,and oxygen-containing functional groups,are responsible for their distinct optical properties,which can be modulated by controlling the deamination and dehydrogenation processes during reactions.Blue,green,yellow,red emissive films,and LEDs are prepared by dispersing the corresponding CDs into polyvinyl alcohol(PVA).All types of white LEDs(WLEDs)with high colorrendering-index(CRI),including warm WLEDs,standard WLEDs,and cool WLEDs,are also fabricated by mixing the red,green,and blue emissive CDs into PVA matrix by the appropriate ratios. 展开更多
关键词 carbon dots solvent-free synthesis full-color luminescence surface state white light emitting diodes
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Post-synthesis and structural evolution of hollow titanium silicalite-1 with solvent-free method 被引量:1
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作者 Yaqi Fan Xianchen Gong +3 位作者 Xiaomeng Si Changjiu Xia Peng Wu Yanhang Ma 《Nano Research》 SCIE EI CSCD 2023年第1期1740-1747,共8页
Generating hollow structure inside titanium silicalite-1(TS-1)is a widely used method to improve its liquid-phase oxidation catalytic performance in industry.However,traditional dissolution-recrystallization method us... Generating hollow structure inside titanium silicalite-1(TS-1)is a widely used method to improve its liquid-phase oxidation catalytic performance in industry.However,traditional dissolution-recrystallization method usually required a large amount of aqueous solution of organic template,leading to unfavorable polluted waste,low production efficiency,and high manufacture cost.Here,a facile and environmental friendly strategy was proposed for the post-synthesis of hollow TS-1 zeolite with a solventfree method utilizing NH4HCO3 and tetrapropylammounium bromide as selective etching agents,which reduced the usage of organic template and avoided the liquid waste.The high crystallinity,the microporous structure,and the active Ti sites were preserved at a high product yield(>93%).The formation mechanism of hollow structure was also investigated by exploring effects of different reactants and experimental parameters.Meanwhile,the obtained hollow TS-1 showed an outstanding performance in the epoxidation of 1-hexene in comparison to the parent zeolite. 展开更多
关键词 hollow structure zeolite post synthesis method solvent-free structural evolution TS-1
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Solvent-free synthesis of highly dispersed zinc-doped porous carbons as efficient dibenzothiophene adsorbents
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作者 Ping Lu Zhenhua Sun +3 位作者 Xinrong Ke Changshen Ye Zhixian Huang Ting Qiu 《Green Energy & Environment》 2025年第5期994-1001,共8页
Designing efficient adsorbents for the deep removal of refractory dibenzothiophene(DBT)from fuel oil is vital for addressing environmental issues such as acid rain.Herein,zinc gluconate and urea-derived porous carbons... Designing efficient adsorbents for the deep removal of refractory dibenzothiophene(DBT)from fuel oil is vital for addressing environmental issues such as acid rain.Herein,zinc gluconate and urea-derived porous carbons SF-ZnNC-T(T represents the carbonization temperature)were synthesized without solvents.Through a temperature-controlled process of“melting the zinc gluconate and urea mixture,forming H-bonded polymers,and carbonizing the polymers,”the optimal carbon,SF-ZnNC-900,was obtained with a large surface area(2280 m^(2)g^(-1),highly dispersed Zn sites,and hierarchical pore structures.Consequently,SF-ZnNC-900 demonstrated significantly higher DBT adsorption capacity of43.2 mg S g^(-1),compared to just 4.3 mg S g^(-1)for the precursor.It also demonstrated good reusability,fast adsorption rate,and the ability for ultra-deep desulfurization.The superior DBT adsorption performance resulted from the evaporation of residual zinc species,which generated abundant mesopores that facilitated DBT transformation,as well as the formation of Zn-N_(x) sites that strengthened the host-vip interaction(ΔE=-1.466 e V).The solvent-free synthesized highly dispersed Zn-doped carbon shows great potential for producing sulfur-free fuel oil and for designing metal-loaded carbon adsorbents. 展开更多
关键词 Adsorptive desulfurization Zn-doped carbon Zn-N cooperation solvent-free
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Active Pillar Array Structure by Solvent-free Liquid Crystal Elastomer Resin
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作者 Chang-Yue Liu Zi-Xuan Wang +2 位作者 Tian-Yu Li Ji-Ping Yang Zhi-Jian Wang 《Chinese Journal of Polymer Science》 2025年第6期1012-1021,I0011,共11页
Bioinspired active pillar structures,known for their large surface area,mechanical compliance,and diverse deformation modes,have garnered extensive research interest.Among various active pillar structures,liquid cryst... Bioinspired active pillar structures,known for their large surface area,mechanical compliance,and diverse deformation modes,have garnered extensive research interest.Among various active pillar structures,liquid crystal elastomer(LCE)pillar arrays are capable of exhibiting significant and reversible anisotropic deformation under cyclic heating and cooling,showing great potential in tunable adhesion,soft robots,and biomedical devices.However,scaling up LCE pillar manufacturing remains challenging,limiting its practical applications.In this work,a solventfree LCE resin is developed with unique features including simple operating procedure,short fabrication time,and tunable responsive temperature,enabling rapid and large-scale production of LCE pillar arrays.The LCE resin allows for the preparation of complex 3D shapes in addition to film or specimen.The fabrication time can be as short as 4 h,without the need to evaporate solvent.Moreover,the LCE resins can be adjusted with a variable phase transition temperature range from 49.4℃ to 97.7℃ by incorporating non-liquid crystal acrylate chains.The resulting active pillar array structure can undertake sequential actuation upon heating with the tunable actuation temperature.Finally,the application of these pillar arrays in multi-level information encryption is demonstrated.The LCE pillar structure introduced here offers a new strategy for constructing advanced active LCE structures with tunable responsive behavior. 展开更多
关键词 Pillar array Liquid crystal elastomer solvent-free resin Multi-level encryption
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Beyond 1 Wh primary coin cells enabled by ultrathick solvent-free processing electrodes
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作者 Yifan Li Dengcheng Liu +6 位作者 Yanyan Lu Nan Qin Mingzhe Xue Cunman Zhang Zonghai Chen Jim PZheng Liming Jin 《Journal of Energy Chemistry》 2025年第10期138-145,共8页
The imperative pursuit of elevated energy density in lithium primary coin cells(LPCCs)necessitates strategic architectural optimization to align with evolving market demands.A predominant approach involves the systema... The imperative pursuit of elevated energy density in lithium primary coin cells(LPCCs)necessitates strategic architectural optimization to align with evolving market demands.A predominant approach involves the systematic replacement of metallic structural support components(MSSCs)to minimize non-active constituent ratios,contingent upon maintaining robust interfacial contact integrity among electrodes,separators,and battery shells.Herein,we present a novel LPCC configuration employing solvent-free processed ultra-thick fluorinated carbon cathode(UCFxC)to achieve complete MSSCs elimination.The engineered UCFxC demonstrates exceptional areal capacity metrics(249.45 mg cm^(-2),215.77 m Ah cm^(-2)),enabling a 27.8% mass reduction compared with conventional laboratoryassembled coin cell while achieving 941.5% energy density enhancement through optimized electrode conductivity.Notably,single-walled carbon nanotube(SWCNT)-modified UCFxC architectures exhibited superior performance with energy exceeding 1.0 Wh at 50℃.This architectural paradigm provides valuable insights for developing next-generation high-energy-density LPCC systems,with practical implications for advancing miniaturized power source technologies. 展开更多
关键词 Lithium primary battery Coin cell solvent-free processing Ultra-thick electrode
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Solvent-free and catalyst-free method for the synthesis of 2,4,5-triarylimidazoles under microwave irradiation
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作者 Jian Feng Zhou Gui Xia Gong +1 位作者 Hui Qin Zhu Feng Xia Zhu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第10期1198-1200,共3页
A facile procedure for the synthesis of 2,4,5-lriarylimidazoles is being reported starting from benzil, aromatic aldehyde and ammonium acetate. The reactions were carried out with catalyst-free, solvent-free and under... A facile procedure for the synthesis of 2,4,5-lriarylimidazoles is being reported starting from benzil, aromatic aldehyde and ammonium acetate. The reactions were carried out with catalyst-free, solvent-free and under microwave irradiation conditions in high yield (80-99%) with short time (3-5 min) and environmental benign, as well as convenient operation. The structures of the compounds have been confirmed on the basis of their IR, 1H NMR, and/or 13C NMR, MS, and elemental analyzer. 展开更多
关键词 Triarylimidazole BENZIL CATALYST-FREE solvent-free Microwave irradiation
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Organic Solvent-Free and Simple Method for Determining Cyromazine and Its Metabolite, Melamine, in Cow’s Milk
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作者 Naoto Furusawa 《Journal of Analytical Sciences, Methods and Instrumentation》 2012年第2期68-73,共6页
This paper described an organic solvent-free, rapid, simple, and space-saving method of sample preparation followed by HPLC coupled photo-diode array (PDA) detector for simultaneous quantification of cyromazine (CYR) ... This paper described an organic solvent-free, rapid, simple, and space-saving method of sample preparation followed by HPLC coupled photo-diode array (PDA) detector for simultaneous quantification of cyromazine (CYR) and its decy-cropropylated metabolite, melamine (MEL), in milk. The HPLC-PDA was performed on an Inertsil? HILIC column with an isocratic aqueous mobile phase. Analytes were extracted from the sample using water, and purified by Mono-Spin?-C18, a centrifugal monolithic silica spin mini-columns, and quantified within 20 min. The method, performed under 100% aqueous conditions, obtained average recoveries for CYR and MEL in the range of 93.2% - 99.1% with relative standard deviations ≤ 2.8%. The quantitation limits were 8.5 ng/mL for CYR and 10 ng/mL for MEL, respectively. No organic solvents were used at any stage of the analysis. 展开更多
关键词 CYROMAZINE MELAMINE HPLC-PDA Milk: ORGANIC solvent-free
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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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A solvent-free process enabling ZnO/porous carbon with enhanced microwave absorption
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作者 Qi Chen Xing Liu +4 位作者 Tingting Wang Xiaogang Su Meng Liu Somboon Chaemchuen Francis Verpoort 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第18期255-264,共10页
Exploring a simple,rapid,solvent-free synthetic method for mass production of cheap,broadband mi-crowave absorbers remains the main challenge.Here,a mild solvent-free procedure is reported to syn-thesize zinc oxide na... Exploring a simple,rapid,solvent-free synthetic method for mass production of cheap,broadband mi-crowave absorbers remains the main challenge.Here,a mild solvent-free procedure is reported to syn-thesize zinc oxide nanoparticles(ZnO NPs)embedded in porous carbon derived from mixing sucrose and zinc nitrate hexahydrate.The characteristic morphology and the ZnO NPs distribution in these compos-ites were tuned using the different raw materials proportions.The mesoporous structure of porous car-bon benefits the compositional advantages between carbon foam and ZnO NPs.The optimal synthesized ZnO/C-2 carbon material demonstrates the strongest absorption of-41.7 dB with a frequency of 14.5 GHz at a thin thickness of 2 mm,and its widest effective absorption is close to 6 GHz(12.2-17.8 GHz).This work produces a feasible route for the sensible design of other effective microwave absorbers for large-scale production. 展开更多
关键词 solvent-free method Porous carbon Dielectric materials Interfacial polarization Microwave broadband absorption
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Influences of process parameters on solvent-free toluene oxidation over Au /γ-MnO_2 catalyst
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作者 姜枫 肖国民 《Journal of Southeast University(English Edition)》 EI CAS 2014年第3期387-390,共4页
γ-MnO2 nanorobs and Au/γ-MnO2 catalysts were synthesized and characterized by the X-ray powder diffraction XRD the scanning electron microscope SEM and transmission electron microscope TEM . The characterizations sh... γ-MnO2 nanorobs and Au/γ-MnO2 catalysts were synthesized and characterized by the X-ray powder diffraction XRD the scanning electron microscope SEM and transmission electron microscope TEM . The characterizations show that Au particles are well dispersed on the surface of γ-MnO2 nanorobs with a particle size of about 10 nm.The catalytic performance is evaluated in solvent-free toluene oxidation with oxygen. The influences of several process parameters such as reaction time reaction temperature initial oxygen pressure and catalyst amounts on the catalytic performance are studied.Catalytic results reveal that Au/γ-MnO2 catalyst has a unique selectivity to benzaldehyde and all these factors greatly influence the conversion of toluene and selectivity of bezaldehyde benzoic acid and benzyl benzoate.However these factors have slight influence on the selectivity of benzyl alcohol. 展开更多
关键词 NANO-GOLD manganese dioxide toluene oxidation solvent-free
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Solvent-free selective oxidation of cyclohexane with molecular oxygen over manganese oxides:Effect of the calcination temperature 被引量:3
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作者 吴明周 詹望成 +5 位作者 郭耘 王筠松 郭杨龙 龚学庆 王丽 卢冠忠 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第1期184-192,共9页
The effects of calcination temperature on the physicochemical properties of manganese oxide catalysts prepared by a precipitation method were assessed by X-ray diffraction,N2 adsorption-desorption,X-ray photoelectron ... The effects of calcination temperature on the physicochemical properties of manganese oxide catalysts prepared by a precipitation method were assessed by X-ray diffraction,N2 adsorption-desorption,X-ray photoelectron spectroscopy,H2 temperature-programmed reduction,O2 temperature-programmed desorption,and thermogravimetry-differential analysis.The catalytic performance of each of these materials during the selective oxidation of cyclohexane with oxygen in a solvent-free system was subsequently examined.It was found that the MnOx-500 catalyst,calcined at 500 °C,consisted of a Mn2O3 phase in addition to Mn5O8 and Mn3O4 phases and possessed a low surface area.Unlike MnOx-500,the MnOx-400 catalyst prepared at 400 °C was composed solely of Mn3O4 and Mn5O8 and had a higher surface area.The pronounced catalytic activity of this latter material for the oxidation of cyclohexene was determined to result from numerous factors,including a higher concentration of surface adsorbed oxygen,greater quantities of the surface Mn4+ ions that promote oxygen mobility and the extent of O2 adsorption and reducibility on the catalyst.The effects of various reaction conditions on the activity of the MnOx-400 during the oxidation of cyclohexane were also evaluated,such as the reaction temperature,reaction time,and initial oxygen pressure.Following a 4 h reaction at an initial O2 pressure of 0.5 MPa and 140 °C,an 8.0% cyclohexane conversion and 5.0% yield of cyclohexanol and cyclohexanone were achieved over the MnOx-400 catalyst.In contrast,employing MnOx-500 resulted in a 6.1% conversion of cyclohexane and 75% selectivity for cyclohexanol and cyclohexanone.After being recycled through 10 replicate uses,the catalytic activity of the MnOx-400 catalyst was unchanged,demonstrating its good stability. 展开更多
关键词 Manganese oxide catalyst Selective oxidation of cyclohexane OXYGEN Calcination temperature solvent-free reaction
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A facile solvent-free synthesis strategy for Co-imbedded zeolite-based Fischer-Tropsch catalysts for direct gasoline production 被引量:7
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作者 Mudassar Javed Shilin Cheng +7 位作者 Guihua Zhang Cederick Cyril Amoo Jingyan Wang Peng Lu Chengxue Lu Chuang Xing Jian Sun Noritatsu Tsubaki 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第4期604-612,共9页
A series of Co-imbedded zeolite-based catalysts were synthesized following a facile solvent-free grinding route.The catalytic performance for direct syngas conversion to gasoline range hydrocarbons was compared with t... A series of Co-imbedded zeolite-based catalysts were synthesized following a facile solvent-free grinding route.The catalytic performance for direct syngas conversion to gasoline range hydrocarbons was compared with their counterpart Co-impregnated zeolite-based catalysts.Successful transformation of solid raw materials to targeted zeolite was confirmed by XRD,SEM,STEM,and N2 physisorption analysis.An in-depth study of acidic strength and acidic site distribution was conducted by NH3-TPD and Py-IR spectroscopy.Acidic strength showed a pivotal role in defining product range.Co@S1,with the weakest acidic strength of silicalite-1 among three types of zeolites,evaded over-cracking of product and exhibited the highest gasoline and isoparaffin selectivity(≈70%and 30.7%,respectively).Moreover,the solvent-free raw material grinding route for zeolite synthesis accompanies several advantages like the elimination of production of wastewater,high product yield within confined crystallization space,and elimination of safety concerns regarding high pressure due to the absence of the solvent.Facileness and easiness of the solvent-free synthesis route together with promising catalytic performance strongly support its application on the industrial scale. 展开更多
关键词 solvent-free synthesis Co-imbedded zeolite catalyst Fischer-Tropsch synthesis Gasoline ISOPARAFFIN
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