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Study of the reaction mechanism for preparing powdered activated coke with SO_(2)adsorption capability via one-step rapid activation method under flue gas atmosphere
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作者 Binxuan Zhou Jingcai Chang +5 位作者 Jun Li Jinglan Hong Tao Wang Liqiang Zhang Ping Zhou Chunyuan Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期158-168,共11页
In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction m... In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction mechanism is summarized.Results indicate that the reaction process of this method can be divided into three stages:stage I is the rapid release of volatiles and the rapid consumption of O_(2),primarily occurring within a reaction time range of 0-0.5 s;stage II is mainly the continuous release and diffusion of volatiles,which is the carbonization and activation coupling reaction stage,and the carbonization process is the main in this stage.This stage mainly occurs at the reaction time range of 0.5 -2.0 s when SL-coal is used as material,and that is 0.5-3.0 s when JJ-coal is used as material;stage III is mainly the activation stage,during which activated components diffuse to both the surface and interior of particles.This stage mainly involves the reaction stage of CO_(2)and H2O(g)activation,and it mainly occurs at the reaction time range of 2.0-4.0 s when SL-coal is used as material,and that is 3.0-4.0 s when JJ-coal is used as material.Besides,the main function of the first two stages is to provide more diffusion channels and contact surfaces/activation sites for the diffusion and activation of the activated components in the third stage.Mastering the reaction mechanism would serve as a crucial reference and foundation for designing the structure,size of the reactor,and optimal positioning of the activator nozzle in PAC preparation. 展开更多
关键词 Reaction mechanism Powdered activated coke preparation SO_(2)adsorption One-step rapid activation Flue gas atmosphere
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INDUCTION—POLYMERIZATION OF PREPARING POLYMERS OF REGULAR STRUCTURE
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作者 Hsiao Lin CHANG, You An Map, Yi Men CHENG Department of Materials Science and Applied Chemistry, National University of Defence Technology, Changsha, 410073 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期821-822,共2页
Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points... Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points and polymerized to polymer of regular structure. Regularity of structure of the polyacrylamide prepared by this means has been verified with electron diffractograms, DSC curve and IR spectrum of the polymer. 展开更多
关键词 MONOMER POLYACRYLAMIDE INDUCTION verified preparing regularly VINYL INDUCTION BOTTLE INTENSE
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AN IMPROVED METHOD FOR PREPARING 2—ALKOXY—5—FLUORO—3H—4—PYRIMIDONE~△
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作者 Chang Jun SUN Zai Cheng CHEN +4 位作者 Yi MENG Yi Gui WANG Peng XUE Jian Guo ZHANG Gui Xiang CUI Department of Chemistry, Shandong University, Jinan 250100 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第7期591-592,共2页
In this paper, we report an improved method for preparing 2--alkoxy 5 fluoro--3H--4--pyrimidone from 2--chloro--5--fluoro--3H--4--pyrimidone and sodium alkoxide under normalpressure at reflux temperature. Some new com... In this paper, we report an improved method for preparing 2--alkoxy 5 fluoro--3H--4--pyrimidone from 2--chloro--5--fluoro--3H--4--pyrimidone and sodium alkoxide under normalpressure at reflux temperature. Some new compounds were synthesized in higher yield by this method. 展开更多
关键词 FLUORO CHLORO preparing substituted ALKOXY FLUORO PYRIMIDONE SYNTHESIZE hydrolysis DEMON
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ON PREPARING TO TEACH ABOUT FROST
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《外语教学》 CSSCI 北大核心 1998年第1期92-97,共6页
ONPREPARINGTOTEACHABOUTFROSTPhilipsSalmanDepartmentofEnglishClevelandStateUniversity【编者按】这篇文章是我院英语学科带头人谭志明教授... ONPREPARINGTOTEACHABOUTFROSTPhilipsSalmanDepartmentofEnglishClevelandStateUniversity【编者按】这篇文章是我院英语学科带头人谭志明教授在美国讲学期间特约的第三篇稿件。本... 展开更多
关键词 英语学科 美国 美利坚合众国 北美洲 稿件 preparing TEACH TO ABOUT FROST ON
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A Scheme for Preparing Schrödinger Cat States with Controllable Manners
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作者 郭光灿 郑仕标 《Chinese Physics Letters》 SCIE CAS CSCD 1997年第6期424-427,共4页
A scheme to generate superpositions of coherent states with variable amplitudes,phases and weighting factors is proposed.It provides experimental possibility for preparing an arbitrary Schrödinger cat state.
关键词 state. preparing ARBITRARY
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STUDY ON THE ELECTROCHEMICAL BEHAVIOR OF ION EXCHANGE MEMBRANE IN PREPARING POTASSIUM CARBONATE
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作者 杨维驿 《Chinese Journal of Chemical Engineering》 SCIE EI CAS 1985年第1期31-47,共17页
This investigation describes the one step preparation of potassium carbonate by electrolysis of potas-sium chloride solution in electrolyzers with various Nation membranes.Potassium bicarbonate solution wasfed to the ... This investigation describes the one step preparation of potassium carbonate by electrolysis of potas-sium chloride solution in electrolyzers with various Nation membranes.Potassium bicarbonate solution wasfed to the cathode compartment,where it was converted into carbonate by reaction with the hydroxideformed at cathode.Because of the low OH^- concentration in the cathode compartment,the back migrationof OH^- through the membrane was almost negligible,resulting in a higher current efficiency,say 90% or more.In this study,electroconductivity,mass transfer,current efficiency and cell voltage were measured.Thefeasibility of the process was discussed and the optimal conditions examined. 展开更多
关键词 KOH STUDY ON THE ELECTROCHEMICAL BEHAVIOR OF ION EXCHANGE MEMBRANE IN preparing POTASSIUM CARBONATE RATE
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Guidelines for Preparing Comprehensive Regional Mafic Dyke Swarm Maps
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作者 Richard E.ERNST Kenneth L.BUCHAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期20-21,共2页
Several regional maps of mafic dyke swarms(e.g.,Buchan and Ernst,2004,2013;Vuollo and Huhma,2005;Peng,2015)have been published in recent years,as well as an earlier global dyke compilation map(Ernst et al.,1996).
关键词 MAPS Guidelines for preparing Comprehensive Regional Mafic Dyke Swarm Maps
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The preparing fibrin sealant powder by using Nitschmann Fraction Ⅰ and Fraction Ⅲ
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《中国输血杂志》 CAS CSCD 2001年第S1期423-,共1页
关键词 The preparing fibrin sealant powder by using Nitschmann Fraction and Fraction
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PREPARING FOR THE 21ST CENTURY:INTRODUCING A SERVICE APPROACH
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《China Population Today》 1995年第Z1期2-4,共3页
PREPARINGFORTHE21STCENTURY:INTRODUCINGASERVICEAPPROACHTheworldknowsChinaforitslargepopulationsize1.2billion-... PREPARINGFORTHE21STCENTURY:INTRODUCINGASERVICEAPPROACHTheworldknowsChinaforitslargepopulationsize1.2billion-andforitsstrongfa... 展开更多
关键词 ST preparing FOR THE 21ST CENTURY
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Tianlian 2-01 is preparing for launch
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作者 XU Zhengqin 《Aerospace China》 2019年第1期2-2,共1页
关键词 preparing LAUNCH
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Preparing for Professional Challenges in the Future
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作者 HOU RUILI 《China Today》 1996年第10期26-28,共3页
PreparingforProfessionalChallengesintheFutureBystaffreporterHOURUILILiYuanxun,famousentrepreneuranddirectoro... PreparingforProfessionalChallengesintheFutureBystaffreporterHOURUILILiYuanxun,famousentrepreneuranddirectorofHarbinBrewery,is... 展开更多
关键词 preparing for Professional Challenges in the Future
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Simplistic Universal Protocols for Remotely Preparing Arbitrary Equatorial States
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作者 MA Song-ya LI Xiang LI Qi 《Chinese Quarterly Journal of Mathematics》 2022年第3期260-273,共14页
We first put forward a deterministic protocol to realize the remote preparation of arbitrary multi-qubit equatorial states via EPR pairs.A set of useful measurement basis is constructed which plays a key role.The rece... We first put forward a deterministic protocol to realize the remote preparation of arbitrary multi-qubit equatorial states via EPR pairs.A set of useful measurement basis is constructed which plays a key role.The receiver just needs to perform Pauli Z operations to recover the target state.Comparing with the previous protocols,the recovery operation is simplified and expressed by a general formula.As there are no universal protocols for high-dimensional systems,we further generalize to the case of multi-qudit equatorial states by means of Fourier transformation.It is worth mentioning that the proposed schemes can be extended to multi-party controlled remote state preparation.Moreover,we consider the effect of two-type decoherence noises. 展开更多
关键词 Remote state preparation Multi-qudit equatorial state Fourier transformation Recovery operation State-independent average fidelity
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A Comparison of Weighing Methods Prior to Fusion Preparing Iron Samples for XRF Analysis
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作者 Louis Lefrancois Perreault Mathieu Bouchard 《Journal of Chemistry and Chemical Engineering》 2019年第2期93-100,共8页
Sample preparation by fusion for XRF analysis is all about knowing the exact weights of the sample and the flux (sample-to-flux ratio). The whole analytical chain, including the weighing step in sample preparation pri... Sample preparation by fusion for XRF analysis is all about knowing the exact weights of the sample and the flux (sample-to-flux ratio). The whole analytical chain, including the weighing step in sample preparation prior to fusion, is of crucial importance to get precise and accurate x-ray fluorescence (XRF) results. Consequently, the weighing method will affect the quality of the analytical results given by the spectrometer. In this study, the effects of different weighing methods on the precision (RSD) of the obtained XRF results are compared to determine the best weighing method for sample preparation by fusion in terms of comparable precisions in the XRF results. 展开更多
关键词 WEIGHING METHOD SAMPLE preparation by FUSION tolerance accepted XRF analysis precision accuracy ANALYTICAL METHOD sample-to-flux ratio ANALYTICAL results AUTOMATIC dispensing balance AUTOMATIC WEIGHING instrument
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Preparing quantum states by measurement-feedback control with Bayesian optimization
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作者 Yadong Wu Juan Yao Pengfei Zhang 《Frontiers of physics》 SCIE CSCD 2023年第6期291-299,共9页
The preparation of quantum states is crucial for enabling quantum computations and simulations.In this work,we present a general framework for preparing ground states of many-body systems by combining the measurement-... The preparation of quantum states is crucial for enabling quantum computations and simulations.In this work,we present a general framework for preparing ground states of many-body systems by combining the measurement-feedback control process(MFCP)with machine learning techniques.Specifically,we employ Bayesian optimization(BO)to enhance the efficiency of determining the measurement and feedback operators within the MFCP.As an illustration,we study the ground state preparation of the one-dimensional Bose−Hubbard model.Through BO,we are able to identify optimal parameters that can effectively drive the system towards low-energy states with a high probability across various quantum trajectories.Our results open up new directions for further exploration and development of advanced control strategies for quantum computations and simulations. 展开更多
关键词 state preparation feedback control Bayesian optimization
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Greening of Coal Mines
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作者 XIA YUANYUAN 《China Today》 2024年第5期32-35,共4页
An Inner Mongolian town takes giant steps in transitioning to clean energy production.AS the Chinese people across the country were preparing to celebrate the Spring Festival holiday,Liu Zhongyuan,a technician at the ... An Inner Mongolian town takes giant steps in transitioning to clean energy production.AS the Chinese people across the country were preparing to celebrate the Spring Festival holiday,Liu Zhongyuan,a technician at the Ruichen Wanniu Livestock Farm in Jungar Zhao Town,Jungar Banner,Inner Mongolia,was busy at work. 展开更多
关键词 BANNER SPRING preparing
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Cancer challenges worldwide and in China:preparing for the inevitable 被引量:3
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作者 Jing Zhou Wang Yang Qiang Liu 《Science China(Life Sciences)》 SCIE CAS CSCD 2022年第2期442-444,共3页
As socioeconomic development is closely associated with changes in various risk factors for cancer,a timely and worldwide depiction of temporal and geographic cancer burden can provide insights on the effective preven... As socioeconomic development is closely associated with changes in various risk factors for cancer,a timely and worldwide depiction of temporal and geographic cancer burden can provide insights on the effective prevention and treatment of this disease.Recently,the International Agency for Research on Cancer issued an update regarding the status of the global cancer burden for 36 forms of cancer in 185 countries(Sung et al.,2021).The report revealed that the worldwide cancer burden had increased rapidly between 2018 and 2020.Notably,female-specific breast cancer has replaced lung cancer as the most commonly diagnosed form,and its incidence rate is increasing rapidly,especially in Asia.Against this background,the study will review and compare global cancer statistics between 2018 and 2020(Sung et al.,2021;Bray et al.,2018),Cancer Country Profiles China 2020(World Health Organization(WHO),2020)。 展开更多
关键词 CANCER PREVENTION preparing
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Effect of chemical regulators on the recovery of leaf physiology,dry matter accumulation and translocation,and yield-related characteristics in winter wheat following dry-hot wind
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作者 Yanan Xu Yue Wu +5 位作者 Yan Han Jiqing Song Wenying Zhang Wei Han Binhui Liu Wenbo Bai 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期108-121,共14页
Dry-hot wind stress causes losses in wheat productivity in major growing regions worldwide,especially winter wheat in the Huang-Huai-Hai Plain of China,and both the occurrence and severity of such events are likely to... Dry-hot wind stress causes losses in wheat productivity in major growing regions worldwide,especially winter wheat in the Huang-Huai-Hai Plain of China,and both the occurrence and severity of such events are likely to increase with global climate change.To investigate the recovery of physiological functions and yield formation using a new noncommercial chemical regulator(NCR)following dry-hot wind stress,we conducted a three-year field experiment(2018-2021)with sprayed treatments of tap water(control),monopotassium phosphate(CKP),NCR at both the jointing and flowering stages(CFS),and NCR only at the jointing stage(FSJ)or flowering stage(FSF).The leaf physiology,biomass accumulation and translocation,grain-filling process,and yield components in winter wheat were assessed.Among the single spraying treatments,the FSJ treatment was beneficial for the accumulation of dry matter before anthesis,as well as larger increases in the maximum grain-filling rate and mean grain-filling rate.The FSF treatment performed better in maintaining a high relative chlorophyll content as indicated by the SPAD value,and a low rate of excised leaf water loss in flag leaves,promoting dry matter accumulation and the contribution to grain after anthesis,prolonging the duration of grain filling,and causing the period until the maximum grain-filling rate reached earlier.The CFS treatment was better than any other treatments in relieving the effects of dry-hot wind.The exogenous NCR treatments significantly increased grain yields by 12.45-18.20% in 2018-2019,8.89-13.82% in 2019-2020,and 8.10-9.00% in 2020-2021.The conventional measure of the CKP treatment only increased grain yield by 6.69% in 2020-2021.The CFS treatment had the greatest mitigating effect on yield loss under dry-hot wind stress,followed by the FSF and FSJ treatments,and the CKP treatment only had a minimal effect.In summary,the CFS treatment could be used as the main chemical control measure for wheat stress resistance and yield stability in areas with a high incidence of dry-hot wind.This treatment can effectively regulate green retention and the water status of leaves,promote dry matter accumulation and efficient translocation,improve the grain-filling process,and ultimately reduce yield losses. 展开更多
关键词 preparation stress foliar spraying GRAIN-FILLING REMOBILIZATION
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Progress in preparation of AlN-reinforced magnesium matrix composites:A review
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作者 Lu Chen Shu-lin Lü +3 位作者 Di-jia Zhao Wei Guo Jian-yu Li Shu-sen Wu 《China Foundry》 SCIE EI CAS CSCD 2024年第1期1-10,共10页
As a ceramic material,AlN has very good thermophysical and mechanical properties.In addition,AlN is an effective refining agent for Mg alloys because it has a lattice constant similar to that of Mg.Therefore,AlN is an... As a ceramic material,AlN has very good thermophysical and mechanical properties.In addition,AlN is an effective refining agent for Mg alloys because it has a lattice constant similar to that of Mg.Therefore,AlN is an ideal reinforcement for magnesium matrix composites(MMCs),and is attracting increasing attention.This review addresses the development of preparation technologies for AlN-reinforced Mg matrix composites.The mainstream preparation techniques include stir casting,melt infiltration,powder metallurgy,and in-situ methods.In addition,the advantages and disadvantages of these techniques are analyzed in depth,and it is pointed out that the next direction for the preparation of high-performance AlN-reinforced MMCs is less aluminization and multiple technologies integration. 展开更多
关键词 ALN MMCS PREPARATION thermophysical property mechanical property
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Synthesis Methods and Property Control of Two-Dimensional Magnetic Materials
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作者 李明爽 李惠敏 刘松 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期112-121,共10页
Two-dimensional(2D)magnetic materials have been demonstrated to have excellent chemical,optical,electrical,and magnetic properties,particularly in the development of multifunctional electronic and spin electronic devi... Two-dimensional(2D)magnetic materials have been demonstrated to have excellent chemical,optical,electrical,and magnetic properties,particularly in the development of multifunctional electronic and spin electronic devices,showcasing tremendous potential.Therefore,corresponding synthesis techniques for 2D magnetic materials that offer high quality,high yield,low cost,time-saving,and simplicity are highly desired.This review provides a comprehensive overview of recent research advances in preparation of magnetic 2D materials,with a particular focus on the preparation methods employed.Moreover,the characteristics and applications of these magnetic materials are also discussed.Finally,the challenges and prospects of synthesis methods for magnetic 2D materials are briefly addressed.This review serves as a guiding reference for the controlled synthesis of 2D magnetic materials. 展开更多
关键词 SYNTHESIS PREPARATION SIMPLICITY
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Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests
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作者 Aleksey S.Ilintsev Elena N.Nakvasina Alexander P.Bogdanov 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期70-80,共11页
This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of forests.This study was conducted on 12 forest sites ... This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of forests.This study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess growth.In the rooting layer,240 soil samples were taken to determine physical properties.The study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina sites.However,reduced soil moisture was noted,particularly in mounds,resulting in increased aeration.In Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the mounds.Mounding treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration porosity.In the Myrtillus and Polytrichum sites,patch scarification had no effects on physical properties.In Polytrichum sites,survival rates,heights,and heigh increments of bareroot Norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to diameter.In Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil treatments.Growing conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth. 展开更多
关键词 Boreal forests Mechanical site preparation Patch scarification MOUNDING Soil properties Containerised seedlings Bareroot seedlings
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