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Thinking on Improving Presentation Teaching-Based on the Empirical Analysis of Presentation in College English Classes of Junior Non-English Majors in Universities of Science and Engineering
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作者 DONG Lin 《Sino-US English Teaching》 2024年第9期424-427,共4页
Based on the empirical investigation of presentation in college English classes for junior non-English majors in science and engineering universities,the author explains her own thinking on how to improve presentation... Based on the empirical investigation of presentation in college English classes for junior non-English majors in science and engineering universities,the author explains her own thinking on how to improve presentation teaching from four aspects:setting teaching objectives,selecting teaching contents,using teaching methods,and evaluating and implementing methods. 展开更多
关键词 PRESENTATION teaching objective teaching content teaching method evaluation on implementation thinking
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A Study on the Application of Audible Thinking Combined with Case Teaching Method in the Teaching of Nursing Room Visits for Trained Nurses
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作者 Xiuying Luo 《Journal of Clinical and Nursing Research》 2024年第8期207-212,共6页
Objective:To investigate the effect of using audible thinking combined with the case teaching method in the teaching of nursing checkups for regulation nurses.Methods:The period was April 2023–April 2024,and a random... Objective:To investigate the effect of using audible thinking combined with the case teaching method in the teaching of nursing checkups for regulation nurses.Methods:The period was April 2023–April 2024,and a randomized controlled group study was carried out in which 76 regulation nurses in our hospital were randomly divided into a research group and a control group,with 38 regulation nurses in each group.The control group used conventional teaching methods,and the research group used audible thinking combined with the case teaching method,comparing the two groups’independent learning ability scores,assessment scores,and teaching satisfaction.Results:Independent learning ability score:after teaching,the research group was significantly higher than the control group(P<0.05);Assessment results:the research group was considerably higher than the control group(P<0.05);Teaching satisfaction:the research group was significantly higher than the control group(P<0.05).Conclusion:The use of audible thinking combined with the case teaching method in the teaching of nursing room visits for trained nurses can improve independent learning ability and assessment results and increase teaching satisfaction. 展开更多
关键词 Audible thinking Case teaching method Trained nurses Nursing room teaching
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Two-Stream Approximation to the Radiative Transfer Equation:A New Improvement and Comparative Accuracy with Existing Methods
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作者 F.Momo TEMGOUA L.Akana NGUIMDO DNJOMO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期278-292,共15页
Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other m... Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the development of the phase function and the intensity into a third-order series of Legendre polynomials. This new approach, which adds one more term in the expression of the intensity and the phase function, allows in the conditions of a plane parallel atmosphere a new mathematical formulation of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta Function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion function of the proposed New Method using the fundamental definition of two-stream approximation(F-TSA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angle μ 0, but tends to deviate from the Disort method with the zenith angle, especially for high values of optical thickness. In spite of this divergence in reflectance for high values of optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained for most cases of optical thickness in this study. An analysis of the Legendre polynomial series for simple functions shows that the high precision is due to the fact that the approximated functions ameliorate the accuracy when the order of approximation increases, although it has been proven that there is a limit order depending on the function from which the precision is lost. This observation indicates that increasing the order of approximation of the phase function of the RTE leads to a better precision in flux calculations. However, this approach may be limited to a certain order that has not been studied in this paper. 展开更多
关键词 Radiative Transfer Equation two-stream method Legendre polynomial optical thickness moments of specific intensity conversion function TRANSMITTANCE reflectance
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Preparation,Characterization and Photothermal Study of PVA/Ti_(2)O_(3) Composite Films
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作者 尚蒙娅 HE Yanyan +3 位作者 YU Jianhui YAN Jiahui XIE Haodi 李金玲 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期658-663,共6页
In this work,flexible photothermal PVA/Ti_(2)O_(3) composite films with different amount(0 wt%,5 wt%,10 wt%,15 wt%)of Ti_(2)O_(3) particles modified by steric acid were prepared by a simple solution casting method.The... In this work,flexible photothermal PVA/Ti_(2)O_(3) composite films with different amount(0 wt%,5 wt%,10 wt%,15 wt%)of Ti_(2)O_(3) particles modified by steric acid were prepared by a simple solution casting method.The microstructures,XRD patterns,FTIR spectra,UV-Vis-NIR spectra thermo-conductivity,thermo-stability and photothermal effects of these composite films were all characterized.These results indicated that Ti_(2)O_(3) particles were well dispersed throughout the polyvinyl alcohol(PVA)matrix in the PVA/Ti_(2)O_(3) composite films.And Ti_(2)O_(3) particles could also effectively improve the photothermal properties of the composite films which exhibited high light absorption and generated a high temperature(about 57.4℃for film with 15 wt%Ti_(2)O_(3) amount)on the surface when it was irradiated by a simulated sunlight source(1 kW/m^(2)). 展开更多
关键词 Ti_(2)O_(3)particles solution casting method composite film photothermal conversion
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Geometric Conversion Approach for the Numerical Evaluation of Hypersin gular and Nearly Hypersingular Boundary Integrals over Curved Surface Boundary Elements
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作者 马杭 《Journal of Shanghai University(English Edition)》 CAS 2002年第2期101-110,共10页
With the aid of the properties of the hypersingular kernels, a geometric conversion approach was presented in this paper. The conversion leads to a general approach for the accurate and reliable numerical evaluation o... With the aid of the properties of the hypersingular kernels, a geometric conversion approach was presented in this paper. The conversion leads to a general approach for the accurate and reliable numerical evaluation of the hypersingular surface boundary integrals encountered in a variety of applications with boundary element method. Based on the conversion, the hypersingularity in the boundary integrals could be lowered by one order, resulting in the simplification of the computer code. Moreover, an integral transformation was introduced to damp out the nearly singular behavior of the kernels by the distance function defined in the local polar coordinate system for the nearly hypersingular case. The approach is simple to use, which can be inserted readily to computer code, thus getting rid of the dull routine deduction of formulae before the numerical implementations, as the expressions of these kernels are in general complicated. The numerical examples were given in three dimensional elasticity, verifying the effectiveness of the proposed approach, which makes it possible to observe numerically the behavior of the boundary integral values with hypersingular kernels across the boundary. 展开更多
关键词 boundary element method numerical evaluation hypersingular boundary integral nearly hypersingular boundary integral geometric conversion.
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Synthesis and Characterization of IR Up-Conversion Material SrS∶Eu, Sm 被引量:1
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作者 卢利平 张希艳 +3 位作者 柏朝晖 王晓春 米晓云 刘全生 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期44-47,共4页
Europium and samarium co-doped strontium sulfide (SrS∶Eu, Sm) infrared up-conversion phosphor was synthesized through calcining the precursor, which prepared by wet-method with strontium carbonate (SrCO_3), sulphur (... Europium and samarium co-doped strontium sulfide (SrS∶Eu, Sm) infrared up-conversion phosphor was synthesized through calcining the precursor, which prepared by wet-method with strontium carbonate (SrCO_3), sulphur (S), europium oxide (Eu_2O_3) and samarium oxide (Sm_2O_3) as the starting materials, lithium fluoride (LiF) as the fluxing agent, at 750~1200 ℃ in carbon-reducing atmosphere. XRD analysis shows that SrS crystal structure is formed at 750 ℃, most completely at 1100 ℃. The IR up-conversion luminescence properties were characterized by excitation, emission, up-conversion excitation, up-conversion emission and thermoluminescence spectra. The spectral analysis associated with the physical model of up-conversion luminescence shows that the IR up-conversion luminescence is resulted from electron trapping process of Sm 3+ energy level. The thermoluminescence peak does not appear below 500 ℃ indicating the trapping energy level is appropriately deep, 800~1400 nm near infrared light can be the release light to realize up-conversion luminescence. 展开更多
关键词 SrS∶ Eu Sm PHOSPHOR IR up-conversion luminescence wet-method rare earths
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An Empirical Study of the Effect of Inquiry Teaching on the Development of High School Students'Critical Thinking Under the New Curriculum Standards
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作者 Chen Yilong Peng Jia 《Contemporary Social Sciences》 2023年第2期130-145,共16页
The Ministry of Education of the People’s Republic of China has issued three guideline documents to encourage inquiry teaching to help students develop their ability to question,which is a defining feature of critica... The Ministry of Education of the People’s Republic of China has issued three guideline documents to encourage inquiry teaching to help students develop their ability to question,which is a defining feature of critical thinking.Two of the documents have clearly stated that English subject teaching should focus on building students’thinking capacity.Critical thinking is an essential feature of building thinking capacity and a key element of the core competencies the English subject seeks to cultivate.This research measures the performance of students of two high school classes in the exams conducted at the beginning,in the middle,and at the end of the experiment period during which inquiry teaching was applied to enhance students’critical thinking ability.The experiment results show that inquiry teaching can improve students’academic performance in English study and help them better develop their language skills.The implementation of the inquiry design in teaching listening,reading,and writing conforms to the law that governs the development of critical thinking,and the adoption of inquiry teaching can promote the development of critical thinking. 展开更多
关键词 new curriculum standards inquiry method high school English learning critical thinking
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On the Conversion of Parts of Speech in English-Chinese Translation
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作者 侯丽香 张春艳 《海外英语》 2017年第19期147-149,共3页
Conversion refers to the transformation of parts of speech in some words while maintaining the original content unchanged in order to make the translated text sound smooth and fluent as well as more idiomatic in the t... Conversion refers to the transformation of parts of speech in some words while maintaining the original content unchanged in order to make the translated text sound smooth and fluent as well as more idiomatic in the target language. In E-C translation, conversion of pars of speech is one of the most important translation methods. Several different forms about conversion of parts of speech are introduced through analyzing the differences and usages between the two languages so that a better version in E-C translation can be got. 展开更多
关键词 E-C translation conversion of parts of Speech methods
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Critical Thinking in the Teaching of University English
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作者 Shuyang Qu 《Journal of Contemporary Educational Research》 2022年第4期81-86,共6页
Critical thinking is a fundamental skill for today’s college students,since it aids in the acquisition of knowledge,correct judgements,and self-adjustment.However,traditional English teaching in China only focuses on... Critical thinking is a fundamental skill for today’s college students,since it aids in the acquisition of knowledge,correct judgements,and self-adjustment.However,traditional English teaching in China only focuses on the development of students’language skills and the inculcation of language knowledge,rather than the cultivation of students’critical thinking skills.This study addresses the aforementioned problem and discusses the definition and significance of critical thinking.Subsequently,it analyzes the causes of L2 students’ineffective critical thinking and proposes several procedures for the training of students in English reading,listening,speaking,and writing. 展开更多
关键词 Critical thinking University English teaching Teaching methods Teaching procedures
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Direct conversion of methane to methanol by electrochemical methods 被引量:3
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作者 Haomin Jiang Luting Zhang +6 位作者 Zhiwei Han Yang Tang Yanzhi Sun Pingyu Wan Yongmei Chen Morris D.Argyle Maohong Fan 《Green Energy & Environment》 SCIE EI CSCD 2022年第6期1132-1142,共11页
A convenient method for methane(CH_(4))direct conversion to methanol(CH_(3)OH)is of great significance to use methane-rich resources,especially clathrates and stranded shale gas resources located in remote regions.The... A convenient method for methane(CH_(4))direct conversion to methanol(CH_(3)OH)is of great significance to use methane-rich resources,especially clathrates and stranded shale gas resources located in remote regions.Theoretically,the activation of CH_(4) and the selectivity to the CH_(3)OH product are challenging due to the extreme stability of CH_(4) and relatively high reactivity of CH_(3)OH.The state-of-the-art‘methane reforming-methanol synthesis’process adopts a two-step strategy to avoid the further reaction of CH_(3)OH under the harsh conditions required for CH_(4) activation.In the electrochemical field,researchers are trying to develop conversion pathways under mild conditions.They have found suitable catalysts to activate the C–H bonds in methane with the help of external charge and have designed the electrode reactions to continuously generate certain active oxygen species.These active oxygen species attack the activated methane and convert it to CH_(3)OH,with the benefit of avoiding over-oxidation of CH_(3)OH,and thus obtain a high conversion efficiency of CH_(4) to CH_(3)OH.This mini-review focuses on the advantages and challenges of electrochemical conversion of CH4 to CH_(3)OH,especially the strategies for supplying electro-generated active oxygen species in-situ to react with the activated methane. 展开更多
关键词 METHANE METHANOL Direct conversion Electrochemical methods Active oxygen species
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MXene quantum dots of Ti_(3)C_(2):Properties,synthesis,and energy-related applications 被引量:1
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作者 Chen Guan Xiaoyang Yue +1 位作者 Jiajie Fan Quanjun Xiang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第10期2484-2499,共16页
The emerging two-dimensional MXene-derived quantum dots(MQDs)have garnered considerable research interest owing to their abundant active edge atoms,excellent electrical conductivity,and remarkable optical properties.C... The emerging two-dimensional MXene-derived quantum dots(MQDs)have garnered considerable research interest owing to their abundant active edge atoms,excellent electrical conductivity,and remarkable optical properties.Compared with their two-dimensional(2D)counterpart MXene,MQDs with forceful size and quantum confinement effects exhibit more unparalleled properties and have considerably contributed to the advanced photocatalysis,detection,energy storage,and biomedicine fields.This critical review summarizes the fundamental properties of MQDs in terms of structure,electricity,and optics.The mechanism,characteristics,and comparisons of two typical synthesis strategies(traditional chemical method and novel fluorine-free or chemical-free method)are also presented.Furthermore,the similarities and differences between MQDs and 2D MXenes are introduced in terms of their functional groups,light absorption capacity,energy band structure,and other properties.Moreover,recent advances in the applications of MQD-based materials for energy conversion and storage(ECS)are discussed,including photocatalysis,batteries,and supercapacitors.Finally,current challenges and future opportunities for advancing MQD-based materials in the promising ECS field are presented. 展开更多
关键词 MXene quantum dots Energy conversion and storage Synthesis method PHOTOCATALYSIS Fundamental property
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The Price of Education
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作者 Erin Strong 《China's Foreign Trade》 2016年第1期63-,共1页
Education is a vital part of life.Right from the beginning you don’t even know you’re undergoing what is actually the most intensive training of your life.Changing useless"blurghs"and"blahs"into&... Education is a vital part of life.Right from the beginning you don’t even know you’re undergoing what is actually the most intensive training of your life.Changing useless"blurghs"and"blahs"into"mama"and"dada"seemed like just a fun bit of mimicry.Complex math was disguised as a game of"how many bananas can a monkey hold?",and the wonders of art developed from applying the first marker you could 展开更多
关键词 VITAL actually MONKEY BEGINNING applying EDUCATIONAL awareness CONVERSATIONAL thinking COMMENTARY
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A research on the composing of sub-health people’s hygienic gymnastics
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作者 Jiao Lizhi 《International Journal of Technology Management》 2016年第6期63-65,共3页
according to statistics, 70 percent of Chinese people are in sub-health, so the health care for them should be payed more attention. In recent years, researches on sub-health people has increased and the classifi cati... according to statistics, 70 percent of Chinese people are in sub-health, so the health care for them should be payed more attention. In recent years, researches on sub-health people has increased and the classifi cation, diagnose for sub-health people’s current situation has entered an area of researching. Among them, the research of sub-health people’s infl uence on society stands out, because the occupational group is tightly related to the promotion of social economic development and stability. Hygienic gymnastics will help to improve sub-health situation and it still need to conduct relatively composing and completing. In this paper, questionnaire method and literature method are used to carry out investigation and analysis on sub-health people and therefore, the hygienic gymnastics for sub-health improving is composed and summarized. 展开更多
关键词 SUB-HEALTH hygienic GYMNASTICS composing thinking METHOD
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An Intermediate Frequency Acquisition Scheme for S-band Single Access Link of the Tracking and Data Relay Satellite System 被引量:1
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作者 马雨出 Gu +2 位作者 Xuemai Zhang Naitong 《High Technology Letters》 EI CAS 2001年第1期31-36,共6页
A nonzero intermediate frequency (IF) likelihood acquisition scheme designed for S-band Single Access (SSA) link of China’s Tracking and Data Relay Satellite System (CTDRSS) is introduced. The received signal is down... A nonzero intermediate frequency (IF) likelihood acquisition scheme designed for S-band Single Access (SSA) link of China’s Tracking and Data Relay Satellite System (CTDRSS) is introduced. The received signal is downconverted to IF, and then direct sampled in IF using a 1-bit A/D. After the digitalization, the sampled data is detected using a hybrid likelihood acquisition scheme. Using this structure, large noise figure of the analog mixer or active filters, amplitude and phase imbalance between low-frequency in-phase and quandrature-phase channel can be avoided. An easy designing algorithm of the acquisition scheme is also derived. The performance and algorithm are verified by computer simulation. 展开更多
关键词 Digital receiver Likelihood detector PN code acquisition Satellite communications
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The Meaning of Divergence
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作者 Wenbing Wu Xiaojian Yuan 《Engineering(科研)》 2023年第12期793-797,共5页
The concept of the divergence is fundamental in electromagnetic field theory, yet they are especially difficult mathematical concepts. Understanding this concept requires strong spatial and abstract thinking. When tea... The concept of the divergence is fundamental in electromagnetic field theory, yet they are especially difficult mathematical concepts. Understanding this concept requires strong spatial and abstract thinking. When teaching, through the graphical and quantitative methods presented herein, the significance of the divergence is displayed by a quantitative method for the first time. Through these methods, the concepts of the divergence can be grasped more easily. These explanations will be helpful for students to strengthen the understanding of this concept and has a certain reference significance. 展开更多
关键词 DIVERGENCE Spatial thinking Quantitative Method
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Hydrothermal synthesis of hexagonal-phase NaYF_4:Er,Yb with different shapes for application as photovoltaic up-converters
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作者 王东丰 张晓丹 +4 位作者 刘永娟 吴春亚 张存善 魏长春 赵颖 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第2期492-498,共7页
Hexagonal β-NaYF4 co-doped with Yb3+ and Er3+ is directly synthesized under mild conditions using a hydrothermal method.The variation of the ratio of Ln3+ to F-and ethylenediaminetetraacetic acid(EDTA) causes th... Hexagonal β-NaYF4 co-doped with Yb3+ and Er3+ is directly synthesized under mild conditions using a hydrothermal method.The variation of the ratio of Ln3+ to F-and ethylenediaminetetraacetic acid(EDTA) causes the shape of the microcrystal to change from microplate to microcolumn.The NaYF4 powder is mixed with polydimethylsiloxane(PDMS) to create an up-converter for thin film amorphous silicon solar cells so as to evaluate the effectiveness of the synthesized material as an up-converter.In order to overcome the difficulty in measuring the effectiveness of up-conversion material,a new method of using near infrared illumination to measure the short circuit current densities of solar cells both with and without up-converters is developed.An up-converter with pure hexagonal NaYF4:Yb3+/Er3+ microcrystal produces a high current output.Emission intensity data obtained by photoluminescence suggest that pure hexagonal NaYF4:Yb3+/Er3+ microcrystals are more efficient than nanocrystals when used as up-converting phosphors. 展开更多
关键词 UP-conversion NAYF4 hydrothermal method up-convertor solar cells
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Preparation of YVO_4:RE(RE=Yb^(3+)/Er^(3+),Yb^(3+)/Tm^(3+))nanoparticles viamicroemulsion-mediated hydrothermal method
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作者 张军 乌兰图雅 +3 位作者 狄晓威 刘志亮 徐刚 徐盛明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第S1期231-235,共5页
A microemulsion-mediated hydrothermal method for synthesis of YVO4:RE(RE=Yb 3+/Er 3+,Yb 3+/Tm 3+)nanoparticles by hydrothermal treatment of quaternary microemulsion medium consisting of Na3VO4/NaOH and RE(NO3)3 aqueou... A microemulsion-mediated hydrothermal method for synthesis of YVO4:RE(RE=Yb 3+/Er 3+,Yb 3+/Tm 3+)nanoparticles by hydrothermal treatment of quaternary microemulsion medium consisting of Na3VO4/NaOH and RE(NO3)3 aqueous solution, surfactant cetyltrimethylammonium bromide(CTAB),cosurfactant n-hexanol and oil phase n-heptane was report.The confinement of microemulsion droplets acting as microreactors during the reaction process allows the formation of small size YVO4:RE nanoparticles with relatively narrow size distribution and less aggregation.The structure,size and shape of YVO4:RE nanoparticles were investigated by means of X-ray diffractometry(XRD)and transmission electron microscopy(TEM).Compared with the conventional solid annealing diffusion method,the microemulsion-mediated hydrothermal method shows superiority in obtaining YVO4:RE nanoparticles with controllable size,narrow size distribution and less aggregation.The microemulsion-mediated hydrothermal method may be potentially applicable for synthesis of other rare earth doped up-converting luminescence nanomaterials. 展开更多
关键词 yttrium orthovanadate doping up-conversion luminescence MICROEMULSION hydrothermal method
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Preparation of Hierarchically Trimodal-Porous ZSM-5 Composites through Steam-assisted Conversion of Macroporous Aluminosilica Gel with Two Different Quaternary Ammonium Hydroxides 被引量:8
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作者 Zhao Tianbo Wang Jia +1 位作者 Xu Xin Wang Guijie 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第1期48-58,共11页
This article presents a detailed structural study of a new spherical Mg Cl2-supported Ti Cl4 Ziegler-Natta catalyst for isotactic propylene polymerization, and researches on the relationship between catalyst structure... This article presents a detailed structural study of a new spherical Mg Cl2-supported Ti Cl4 Ziegler-Natta catalyst for isotactic propylene polymerization, and researches on the relationship between catalyst structure and polymer properties. The spherical support with the chemical composition of CH3CH2 OMg OCH(CH2Cl)2 has been synthesized from a new dispersion system and is used as the supporting material to prepare Ziegler-Natta catalyst. The XRD analysis indicates that the catalyst is fully activated with δ-Mg Cl2 in the active catalyst. The far-IR spectrometric results confirm again the presence of δ-Mg Cl2 in the active catalyst. Textural property of the active catalyst exhibits high surface area coupled with high porosity. The high activity in propylene polymerization is mainly ascribed to the full activation and the porous structure of the catalyst. Scanning electron microscopy/energy dispersive spectrometer mapping results indicate a uniform titanium distribution throughout the catalyst particles. Particle size analysis shows that the catalyst has a narrow particle size distribution. The perfect spherical shape, uniform titanium distribution and narrow particle size distribution of the catalyst confirm the advantage of polymer particles production with less fines. The solid state 13 C NMR and mid-IR spectroscopic analyses indicate that there exists strong complexation between diisobutyl phthalate and Mg Cl2, which leads to the high isotacticity of polypropylene. 展开更多
关键词 ZSM-5 composites hierarchically trimodal-porous steam-assisted conversion method MACROPOROUS aluminosilicagel quaternary ammonium hydroxide
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Conversion factor analysis of self-balanced loading test of cast-in-situ piles based on analogue test method 被引量:3
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作者 Li Jianhang Li Xiaojuan +2 位作者 Gao Luchao Dai Guoliang Wu Weiguo 《Journal of Southeast University(English Edition)》 EI CAS 2019年第2期185-190,共6页
Based on the characteristics of pile-soil interaction and the Mohr-Coulomb strength theory,a new method of determining the side friction at a pile-soil interaction is proposed.Combined with the actual engineering case... Based on the characteristics of pile-soil interaction and the Mohr-Coulomb strength theory,a new method of determining the side friction at a pile-soil interaction is proposed.Combined with the actual engineering cases,the effectiveness of the analogue test method is verified by comparing it with the traditional anchor pile method and self-balanced method.Taking the self-balanced test of the bridge pile foundation in the Songhua River as an example,the conversion factor of sandy soil and weathered mudstone are confirmed by the analogue test method.The results show that the conversion factor of sandy soil and weathered mudstone in the Songhua River area should consider the geological conditions and the construction technology,etc.The standard values are relatively conservative.It is suggested that the engineering application should be properly revised.The recommended range of the conversion factor of sandy soil in this area is 0.65 to 0.85,and that of weathered mudstone is 1.0. 展开更多
关键词 cast-in-situ piles self-balanced method analogue test method Mohr-Coulomb strength theory conversion factor
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Catalytic Conversion of Alcohol to Corresponding Alkyl Chlorides
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作者 Chen Zhang-ping Zhang Xuan +1 位作者 Li Xue-lian Wu Xuan-jie 《Wuhan University Journal of Natural Sciences》 CAS 2000年第2期232-232,共1页
1-chloro-octane, 1-chloro-dedocane and 1-chloro-hexadecane are synthesized from the corresponding alcohols. The reactions are catalyzed by N, N-dimethyl formamide and dodecyltrimethyl animonium chloride, not only the ... 1-chloro-octane, 1-chloro-dedocane and 1-chloro-hexadecane are synthesized from the corresponding alcohols. The reactions are catalyzed by N, N-dimethyl formamide and dodecyltrimethyl animonium chloride, not only the reaction time has been reduced, but also the yield improved from 10%~20%. 展开更多
关键词 ALCOHOL alkyl chlorides catalytic conversion synthetic method
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