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词尾“化”的来源、意义及“X化”动词语义特征 被引量:5
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作者 史红改 《北京广播电视大学学报》 2009年第2期41-44,共4页
通过追根溯源,认为"化"尾是由单音节动词"化"虚化而来的,它的产生是多种因素共同作用的结果;此外,文章还讨论了"X化"动词的语义特征,提出"化"是表示变化发展,"X"表明变化发展的方向。
关键词 “x化”动词 词尾“化” 语义特征
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“副X”、“副X化”和“X化”的转化机制
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作者 梁世红 窦艳 《牡丹江师范学院学报(社会科学版)》 2003年第3期29-31,共3页
本文对具有副X化、副X和X化三类形式的化缀词进行归类考察,分析三种形式存在和转化的语义基础及语法功能,指出它们都具有形容词的语义特征,而且“名词+化”和“形容词+化”的三种形式的成立呈现出一种镜像关系。
关键词 汉语 语法 语义基础 语法功能 镜像关系 语义特征 形容词 “副x “副x化” “x化” 缀词
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“X化”结构研究概述
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作者 沈思芹 《赤峰学院学报(哲学社会科学版)》 2015年第10期183-184,共2页
"X化"结构以其在现代汉语中较高的使用频率而颇受关注。目前对其研究主要包括"化"的语义特征、语法性质及来源,"X化"的结构特征,"X化"的语义特征和语法功能三个方面。研究理论框架既有传统的... "X化"结构以其在现代汉语中较高的使用频率而颇受关注。目前对其研究主要包括"化"的语义特征、语法性质及来源,"X化"的结构特征,"X化"的语义特征和语法功能三个方面。研究理论框架既有传统的语言学理论又有语法化等现代语言学理论,但在对"X化"的研究中,仍然存在着很多分歧,对其的归纳和总结有利于进一步探索相关语言规律。 展开更多
关键词 “x化” 化” 语法 词缀
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“X化”动词的论旨结构与否定
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作者 史红改 《莆田学院学报》 2009年第4期32-34,共3页
现代汉语"X化"动词存在两种论旨结构:一元结构和二元结构。双音节"X化"动词是无标记动词,三音节以上的"X化"动词是有标记动词。此外,"X化"动词的肯定形式与否定形式在使用上存在不对称性。
关键词 “x化”动词 论旨结构 词汇 不对称
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“X+fy”和“X+化”词化与句法对比
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作者 刘亚丹 罗思明 《现代语文(下旬.语言研究)》 2017年第9期139-142,共4页
本文以英汉语言中"X+fy"和"X+化"的词化模式、对称与不对称性及其句法特征的异同为研究内容。研究发现:英汉语言中都具有"名词+fy/化"和"形容词+fy/化"两种词化模式;但存在语内和语际的对称性... 本文以英汉语言中"X+fy"和"X+化"的词化模式、对称与不对称性及其句法特征的异同为研究内容。研究发现:英汉语言中都具有"名词+fy/化"和"形容词+fy/化"两种词化模式;但存在语内和语际的对称性和不对称性;英汉语在句法上存在差异。"形容词+fy"和"形容词+化"的句法相似,"名词+化"具有句法特殊性。英语两种词化模式所得到的动词都具有及物性,一般能带宾语,被动语,部分副词,祈使语。汉语中"形容词+化"和"名词+化"句法功能有差异,"形容词+化"能作谓语,不作宾语,用于被动句,不用在祈使句中;"名词+化"一般可作宾语,能用在被动句中,可受部分副词修饰,不能作谓语,不用在祈使句中。 展开更多
关键词 “x+fy” “x+化” 对称与不对称性 句法
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现代汉语“X+化”派生词中“X”词性的界定
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作者 罗健京 邓云华 《海外英语》 2015年第12期217-219,共3页
词性的界定是语言研究的基础。该研究以现代汉语"X+化"派生词为研究对象,采用定性与定量结合的方法,从句法功能和语义特征两方面分别讨论了对于现代汉语"X+化"派生词中"X"词性的界定。研究表明,仅靠"... 词性的界定是语言研究的基础。该研究以现代汉语"X+化"派生词为研究对象,采用定性与定量结合的方法,从句法功能和语义特征两方面分别讨论了对于现代汉语"X+化"派生词中"X"词性的界定。研究表明,仅靠"X"的句法功能是不能判定词性的,要以语义为基础,分析"化"字和"X"的语义特征,再结合句法功能判定规则,是确定词性的最佳路径。 展开更多
关键词 现代汉语“x+化”派生词 词性界定
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现代汉语“X来”式合成词溯源 被引量:23
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作者 梁银峰 《语言科学》 CSSCI 北大核心 2009年第4期412-421,共10页
文章把现代汉语"X来"式合成词分为四类:"古来"类、"从来"类、"后来"类、"想来"类。这四类"X来"内部结构不同,历史来源也不同。具体来说,"古来"类来源于汉语史... 文章把现代汉语"X来"式合成词分为四类:"古来"类、"从来"类、"后来"类、"想来"类。这四类"X来"内部结构不同,历史来源也不同。具体来说,"古来"类来源于汉语史上表时间的方位短语"自/从X以来",出于语言的经济原则,"自/从X以来"缩略为"X来";"从来"类来源于汉语史上具有名词功能的短语"所X来","X"和"来"本不在同一结构层次上,由于经常相邻出现,逐渐跨层词汇化为双音词;"后来"类直接从动词性偏正短语"X来"词汇化而来,不像前两类"X来"经过了形式上的缩减过程;"想来"类来源于动趋式"X来"的泛化,"来"逐渐由趋向动词(作补语)虚化为类词缀。 展开更多
关键词 合成词 结构 差异 来源 词汇 语法“x来”
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Enhanced visible light photocatalytic H_2 production over Z-scheme g-C_3N_4 nansheets/WO_3 nanorods nanocomposites loaded with Ni(OH)_x cocatalysts 被引量:8
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作者 何科林 谢君 +5 位作者 罗杏宜 温九青 马松 李鑫 方岳平 张向超 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期240-252,共13页
Novel WO3/g-C3N4/Ni(OH)x hybrids have been successfully synthesized by a two-step strategy of high temperature calcination and in situ photodeposition.Their photocatalytic performance was investigated using TEOA as ... Novel WO3/g-C3N4/Ni(OH)x hybrids have been successfully synthesized by a two-step strategy of high temperature calcination and in situ photodeposition.Their photocatalytic performance was investigated using TEOA as a hole scavenger under visible light irradiation.The loading of WO3 and Ni(OH)x cocatalysts boosted the photocatalytic H2 evolution efficiency of g-C3N4.WO3/g-C3N4/Ni(OH)x with 20 wt%defective WO3 and 4.8 wt%Ni(OH)x showed the highest hydrogen production rate of 576 μmol/(g·h),which was 5.7,10.8 and 230 times higher than those of g-C3N4/4.8 wt%Ni(OH)x,20 wt%WO3/C3N4 and g-C3N4 photocatalysts,respectively.The remarkably enhanced H2 evolution performance was ascribed to the combination effects of the Z-scheme heterojunction(WO3/g-C3N4) and loaded cocatalysts(Ni(OH)x),which effectively inhibited the recombination of the photoexcited electron-hole pairs of g-C3N4 and improved both H2 evolution and TEOA oxidation kinetics.The electron spin resonance spectra of ·O2^- and ·OH radicals provided evidence for the Z-scheme charge separation mechanism.The loading of easily available Ni(OH)x cocatalysts on the Z-scheme WO3/g-C3N4 nanocomposites provided insights into constructing a robust multiple-heterojunction material for photocatalytic applications. 展开更多
关键词 Photocatalytic hydrogen evolution Robust Ni(OH)x cocatalyst g-C3N4 Z-Scheme systems Heterojunction
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Understanding the roles of Brønsted/Lewis acid sites on manganese oxide-zeolite hybrid catalysts for low-temperature NH_(3)-SCR
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作者 Hyun Sub Kim Hwangho Lee +2 位作者 Hongbeom Park Inhak Song Do Heui Kim 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期79-88,共10页
Although metal oxide-zeolite hybrid materials have long been known to achieve enhanced catalytic activity and selectivity in NO_(x)removal reactions through the inter-particle diffusion of intermediate species,their s... Although metal oxide-zeolite hybrid materials have long been known to achieve enhanced catalytic activity and selectivity in NO_(x)removal reactions through the inter-particle diffusion of intermediate species,their subsequent reaction mechanism on acid sites is still unclear and requires investigation.In this study,the distribution of Brønsted/Lewis acid sites in the hybrid materials was precisely adjusted by introducing potassium ions,which not only selectively bind to Brønsted acid sites but also potentially affect the formation and diffusion of activated NO species.Systematic in situ diffuse reflectance infrared Fourier transform spectroscopy analyses coupled with selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR)reaction demonstrate that the Lewis acid sites over MnO_(x)are more active for NO reduction but have lower selectivity to N_(2)than Brønsted acids sites.Brønsted acid sites primarily produce N_(2),whereas Lewis acid sites primarily produce N_(2)O,contributing to unfavorable N_(2)selectivity.The Brønsted acid sites present in Y zeolite,which are stronger than those on MnO_(x),accelerate the NH_(3)-SCR reaction in which the nitrite/nitrate species diffused from the MnO_(x)particles rapidly convert into the N_(2).Therefore,it is important to design the catalyst so that the activated NO species formed in MnO_(x)diffuse to and are selectively decomposed on the Brønsted acid sites of H-Y zeolite rather than that of MnO_(x)particle.For the physically mixed H-MnO_(x)+H-Y sample,the abundant Brønsted/Lewis acid sites in H-MnO_(x)give rise to significant consumption of activated NO species before their inter-particle diffusion,thereby hindering the enhancement of the synergistic effects.Furthermore,we found that the intercalated K+in K-MnO_(x)has an unexpected favorable role in the NO reduction rate,probably owing to faster diffusion of the activated NO species on K-MnO_(x)than H-MnO_(x).This study will help to design promising metal oxide-zeolite hybrid catalysts by identifying the role of the acid sites in two different constituents. 展开更多
关键词 Hybrid metal oxide-zeolite The role of acid sites Manganese oxides Physical mixing Selective catalytic reduction of NO_(x)with NH_(3)
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Highly efficient Z-scheme WO_(3-x) quantum dots/TiO_2 for photocatalytic hydrogen generation 被引量:6
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作者 潘伦 张靖雯 +4 位作者 贾旭 马煜航 张香文 王莅 邹吉军 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期253-259,共7页
Z-scheme semiconductors are a promising class of photocatalysts for hydrogen generation.In this work,Z-scheme semiconductors composed of WO3-x quantum dots supported on TiO2(WO3-xQDS/TiO2) were fabricated by solvoth... Z-scheme semiconductors are a promising class of photocatalysts for hydrogen generation.In this work,Z-scheme semiconductors composed of WO3-x quantum dots supported on TiO2(WO3-xQDS/TiO2) were fabricated by solvothermal and hydrogen-reduction methods.Characterization by transmission electron microscopy and X-ray diffraction indicated that the amount and size of the WO3-x QDs could be tuned by modulating the addition of the W precursor.Evidence from X-ray photoelectron spectroscopy and photoluminescence spectroscopy suggested that the hydrogen reduction of the composite induced the formation of oxygen vacancy(W^5+/Vo) defects in WO3.These defects led to ohmic contact between WO3-x and TiO2,which altered the charge-transfer pathway from type Ⅱ heterojunction to Z-scheme,and maintained the highly reductive and oxidative ability of TiO2 and WO3-x,respectively.Therefore,the Z-scheme sample showed 1.3-fold higher photoactivity than pure TiO2 in hydrogen generation.These results suggest that the formation of W^5+/Vo defects at the interface is highly beneficial for the fabrication of Z-scheme photocatalysts. 展开更多
关键词 WO3–x Titanium oxide Hydrogen generation Quantum dots W^5+/oxygen vacancy defect
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Analysis of electrochemical impedance and XRD spectroscopy for complex self-assembled film on silver 被引量:5
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作者 王怡红 宋伟 +2 位作者 高李憬 葛杰 顾宁 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期121-124,共4页
Self-assembled monolayers (SAMs) of (3-mercaptopropy) trimethoxysilane (3-MtrF) chemisorbed on silver surfaces were chemically "modified by 1-octadecanethiol to form self-assembled mixed-monolayers (SAMM) and... Self-assembled monolayers (SAMs) of (3-mercaptopropy) trimethoxysilane (3-MtrF) chemisorbed on silver surfaces were chemically "modified by 1-octadecanethiol to form self-assembled mixed-monolayers (SAMM) and the co-polymer of N-vinylcarbazole and methyl methacrylate ester (to form complex selfassembled film (CSAF)). The oxidation resistance of these barriers on silver surfaces and some influential factors concerned processes were analyzed by electrochemical impedance spectroscopy (EIS) in a 10% NaOH aqueous solution at oxidation potential. X-ray diffraction (XRD) spectroscopy shows that the oxidation occurring on the silver surface may be restrained effectively due to the coating barrier, and CSAF(Ⅱ) is the best one. Studies also reveal that oxide processes of bare silver and a series of modified silver electrodes in a 10% NaOH aqueous solution are of more than two relaxation time constants. 展开更多
关键词 electrochemical impedance x-ray diffraction complex self-assembled multilayer SILVER
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语素“化”的研究综述
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作者 沈思芹 《开封教育学院学报》 2015年第9期27-28,共2页
"X化"结构以其在现代汉语中较高的使用频率而颇受关注,对其结构中所含语素"化"的研究是一个重要方面。对语素"化"的语义特征、语法性质、语法功能、来源、读音及语法化动因等方面进行研究,有利于进一步探... "X化"结构以其在现代汉语中较高的使用频率而颇受关注,对其结构中所含语素"化"的研究是一个重要方面。对语素"化"的语义特征、语法性质、语法功能、来源、读音及语法化动因等方面进行研究,有利于进一步探索"X化"结构,也有利于深入研究词缀的共性与个性问题。但目前语素"化"的研究中仍然存在诸多分歧,需要适当引入新理论,进一步拓宽研究的深度和广度。 展开更多
关键词 “x化” 化” 语法 词缀
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Determination of Structure and Polarity of Si C Single Crystal by X-Ray Diffraction Technique 被引量:1
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作者 郑新和 渠波 +2 位作者 王玉田 杨辉 梁骏吾 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第1期35-39,共5页
Structure and polarity of the Si C single crystal have been analyzed with the four- circle X- ray diffraction method by a double- crystal diffractom eter.The hexagonal{ 10 15 } pole figure shows that this Si C sam pl... Structure and polarity of the Si C single crystal have been analyzed with the four- circle X- ray diffraction method by a double- crystal diffractom eter.The hexagonal{ 10 15 } pole figure shows that this Si C sam ple has a6 H modification.The difference between the integrated intensities m easured byω scan in the triple- axis diffraction set- up finds some convincing evidence that the surface is either a Si- terminated face or C- terminated face.The experi- mental ratios of| F( 0 0 0 L) | 2 / | F( 0 0 0 L) | 2 are in good agreem entwith the calculated ones after the dispersion cor- rections to the atomic scattering factors( L=6 ,12 and18,respectively) .Thus,this m easurem ent technique is con- venient for the application of the materials with remarkable surface polarity. 展开更多
关键词 Si C single crystal polarity hexagonal6 H scattering factor
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Photoelectrocatalytic reduction of CO_2 into formic acid using WO_(3-x)/TiO_2 film as novel photoanode 被引量:2
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作者 杨亚辉 解人瑞 +3 位作者 黎航 刘灿军 刘文华 占发琦 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第9期2390-2396,共7页
A novel WO3-x/TiO2 film as photoanode was synthesized for photoelectrocatalytic(PEC) reduction of CO2 into formic acid(HCOOH). The films prepared by doctor blade method were characterized with X-ray diffractometer... A novel WO3-x/TiO2 film as photoanode was synthesized for photoelectrocatalytic(PEC) reduction of CO2 into formic acid(HCOOH). The films prepared by doctor blade method were characterized with X-ray diffractometer(XRD), scanning electron microscope(SEM) and transmission electron microscope(TEM). The existence of oxygen vacancies in the WO3-x was confirmed with an X-ray photoelectron spectroscopy(XPS), and the accurate oxygen index was determined by a modified potentiometric titrimetry method. After 3h of photoelectrocatalytic reduction, the formic acid yield of the WO3-x/TiO2 film is 872 nmol/cm^2, which is 1.83 times that of the WO3/TiO2 film. The results of PEC performance demonstrate that the introduction of WO3-x nanoparticles can improve the charge transfer performance so as to enhance the performance of PEC reduction of CO2 into formic acid. 展开更多
关键词 photoelectrocatalytic reduction CO2 formic acid WO3-x TiO2 film photoanode
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XML Based Data Cube and X-OLAP
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作者 王晓玲 董逸生 《Journal of Southeast University(English Edition)》 EI CAS 2001年第2期5-9,共5页
Data warehouse provides storage and management for mass data, but data schema evolves with time on. When data schema is changed, added or deleted, the data in data warehouse must comply with the changed data schema, ... Data warehouse provides storage and management for mass data, but data schema evolves with time on. When data schema is changed, added or deleted, the data in data warehouse must comply with the changed data schema, so data warehouse must be re organized or re constructed, but this process is exhausting and wasteful. In order to cope with these problems, this paper develops an approach to model data cube with XML, which emerges as a universal format for data exchange on the Web and which can make data warehouse flexible and scalable. This paper also extends OLAP algebra for XML based data cube, which is called X OLAP. 展开更多
关键词 data warehouse data cube xML x OLAP semi structured data
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INTERFACIAL BONDING IN AS DEPOSITED AND ANNEALED Co/C SOFT X RAY MULTILAYER MIRRORS
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作者 白海力 姜恩永 +1 位作者 王存达 田仁玉 《Transactions of Tianjin University》 EI CAS 1998年第2期80-85,共6页
Interfacial bonding in as deposited and annealed Co/C soft X ray multilayer structures is investigated by X ray photo electron spectroscopy (XPS).It is found that there is interdiffusion between cobalt and carbon ... Interfacial bonding in as deposited and annealed Co/C soft X ray multilayer structures is investigated by X ray photo electron spectroscopy (XPS).It is found that there is interdiffusion between cobalt and carbon in the as deposited Co/C multilayers,and this is confirmed by structure characterization using low angle X ray diffraction (LAXD).The calculation of the chemical shifts in Co C system based on Miedemas macroscopic atom model suggests that it is impossible to detect the chemical shift experimentally in the Co C compound,which is consistent with the XPS results.The presence of metallic carbide bonding is evidenced through the nature of the carbon bonding in survey taken at Co C and C Co interfaces of annealed samples.Our results also indicate that XPS is a direct method to probe the chemical bonding at the interfaces. 展开更多
关键词 soft x ray MULTILAYERS interfacial bonding thermodynamic properties
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Construction of LSPR-enhanced 0D/2D CdS/MoO3‒x S-scheme heterojunctions for visible-light-driven photocatalytic H2 evolution 被引量:19
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作者 Jinjun Peng Jun Shen +3 位作者 Xiaohui Yu Hua Tang Zulfiqar Qinqin Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期87-96,共10页
Plasmonic nonmetal semiconductors with localized surface plasmon resonance(LSPR)effects possess extended light-response ranges and can act as highly efficient H2 generation photocatalysts.Herein,an LSPR-enhanced 0D/2D... Plasmonic nonmetal semiconductors with localized surface plasmon resonance(LSPR)effects possess extended light-response ranges and can act as highly efficient H2 generation photocatalysts.Herein,an LSPR-enhanced 0D/2D CdS/MoO3‒x heterojunction has been synthesized by the growth of 0D CdS nanoparticles on 2D plasmonic MoO3‒x elliptical nanosheets via a simple coprecipitation method.Taking advantage of the LSPR effect of the MoO3‒x elliptical nanosheets,the light absorption of the CdS/MoO3‒x heterojunction was extended from 600 nm to the near-infrared region(1400 nm).Furthermore,the introduction of 2D plasmonic MoO3‒x elliptical nanosheets not only provided a platform for the growth of CdS nanoparticles,but also contributed to the construction of an LSPR-enhanced S-scheme structure due to the interface between the MoO3‒x and CdS,accelerating the separation of light-induced electrons and holes.Therefore,the CdS/MoO3‒x heterojunction exhibited higher photocatalytic H2 generation activity than pristine CdS under visible light irradiation,including under 420,450,550,and 650 nm monochromic light,as well as improved photo-corrosion performance. 展开更多
关键词 CDS MoO3‒x Photocatalytic H2 evolution S-scheme Localized surface plasmon resonance effect
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Combustion and NO_x Emission Behavior of Chinese Coals 被引量:3
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作者 陈宏刚 谢克昌 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第3期333-338,共6页
Seven Chinese coals ranking from anthracite to sub-bituminous fromthe Shanxi province were selected for study to forecast thecombustion and NO_x emission behavior. Three UK, one Indonesia andone South Africa coal was ... Seven Chinese coals ranking from anthracite to sub-bituminous fromthe Shanxi province were selected for study to forecast thecombustion and NO_x emission behavior. Three UK, one Indonesia andone South Africa coal was included in the study for reference. A flatflame-turbulent jet apparatus was employed to assess flame stability,ignition performance and NO_x emission behavior for the initial stageof devolatilization and combustion. This apparatus can simulateparticle heating rates, maximum temperatures and the influence of theturbulent Fluid interactions on the fate of volatiles. 展开更多
关键词 DEVOLATILIZATION char reactivity SLAGGING NO_x
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Support effect of zinc tin oxide on gold catalyst for CO oxidation reaction
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作者 李威 杜林颖 +1 位作者 贾春江 司锐 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第10期1702-1711,共10页
Nanostructured gold catalyst supported on metal oxide is highly active for the CO oxidation reac‐tion. In this work, a new type of oxide support, zinc tin oxide, has been used to deposit 0.7 wt%Au via a deposition‐p... Nanostructured gold catalyst supported on metal oxide is highly active for the CO oxidation reac‐tion. In this work, a new type of oxide support, zinc tin oxide, has been used to deposit 0.7 wt%Au via a deposition‐precipitation method. The textural properties of Zn2SnO4 support have been tuned by varying the molar ratio between base (N2H4&#183;H2O) and metal ion (Zn2+) to be 4/1, 8/1 and 16/1. The catalytic tests for CO oxidation reaction revealed that the reactivity on Au‐Zn2SnO4 with N2H4&#183;H2O/Zn2+ = 8/1 was the highest, while the reactivity on Au‐Zn2SnO4 with N2H4&#183;H2O/Zn2+ =16/1 was almost identical to that of the pure support. Both fresh and used catalysts have been characterized by multiple techniques including nitrogen adsorption‐desorption, X‐ray diffraction, transmission electron microscopy, high‐angle annular dark‐field scanning transmission electron microscopy, X‐ray photoelectron spectroscopy, X‐ray adsorption fine structure, and tempera‐ture‐programmed reduction by hydrogen. These demonstrated that the textural properties, espe‐cially pore volume and pore size distribution, of Zn2SnO4 play crucial roles in the averaged size of gold nanoparticles, and thus determine the catalytic activity of Au‐Zn2SnO4 for CO oxidation. 展开更多
关键词 Gold catalyst Zinc tin oxide Carbon monoxide oxidation x-ray absorption fine structure Structure-activity relationship
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Photocatalytic C–X borylation of aryl halides by hierarchical SiC nanowire-supported Pd nanoparticles 被引量:1
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作者 Zhi-Feng Jiao Ji-Xiao Zhao +1 位作者 Xiao-Ning Guo Xiang-Yun Guo 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第2期357-363,共7页
Hierarchical Si C nanowire-supported Pd nanoparticles showed high photocatalytic activity for the C–X(X = Br, I) borylation of aryl halides at 30 °C. The Si C/Pd Mott-Schottky contact enhances the rapid transfer... Hierarchical Si C nanowire-supported Pd nanoparticles showed high photocatalytic activity for the C–X(X = Br, I) borylation of aryl halides at 30 °C. The Si C/Pd Mott-Schottky contact enhances the rapid transfer of the photogenerated electrons from Si C to the Pd nanoparticles. As a result, the concentrated energetic electrons in the Pd nanoparticles can facilitate the cleavage of C–I or C–Br bonds, which normally requires high-temperature thermal processes. We show that the present Pd/Si C photocatalyst is capable of catalyzing the transformation of a large variety of aryl halides to their corresponding boronate esters under visible light irradiation, with excellent yields. 展开更多
关键词 Boronate esters Carbon-halogen activation Hierarchical SiC nanowires Pd nanoparticles Photocatalysis
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