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Microstructure Characteristics and Possible Phase Evolution of the Coal Gangue-Steel Slag Ceramics Prepared by the Solid-State Reaction Methods
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作者 刘文洁 WANG Yang +1 位作者 LI Jingtao 李宝让 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期921-930,共10页
Industrial wastes such as steel slag and coal gangue etc.were chosen as raw materials for preparing ceramic via the conventional solid-state reaction method.With steel slag and coal gangue mixed in various mass ratios... Industrial wastes such as steel slag and coal gangue etc.were chosen as raw materials for preparing ceramic via the conventional solid-state reaction method.With steel slag and coal gangue mixed in various mass ratios,from 100%steel slag to 100%coal gangue at 10%intervals,microstructure and possible phase evolution of the coal gangue-steel slag ceramics were investigated using X-ray powder diffraction,scanning electron microscopy,mercury intrusion porosimetry and Archimedes boiling method.The experimental results suggest that the phase compositions of the as-prepared ceramics could be altered with the increased amount of coal gangue in the ceramics.The anorthite-diopside eutectic can be formed in the ceramics with the mass ratios of steel slag to coal gangue arranged from 8:2 to 2:8,which was responsible for the melting of the steel slag-coal gangue ceramics at relatively high temperature.Further investigations on the microstructure suggested that the addition of the proper amount of steel slag in ceramic compositions was conducive to the pore formation and further contributed to an increment in porosity. 展开更多
关键词 steel slag-coal gangue ceramics synthesis phase evolution microstructure characteristics
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Influence of Ti Powder Characteristics on Combustion Synthesis of Porous NiTi Alloy
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作者 YonghuaLI V.E.Gunther 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2002年第3期248-250,共3页
关键词 Porous NiTi shape memory alloy Combustion synthesis Titanium powder characteristics
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THE STUDYOF SYNTHESIS AND CHARACTERISTICS OF POLYPHENYLACETYLENE USING WOBr_4AS CATALYST
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作者 Yin Kui LI Zhao Hui CHEN Department of Materials Science and Applied Chemistry,Changsha Institute of Technology,Changsha 410003 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第1期51-52,共2页
A new kind of catalyst WOBr_4,which can be used in the polymerization of phenylacetylene(PhA),has been synthesized.The obtained polyphenylcetylene(PPhA) using WOBr_4 as catalyst is soluble、fusible、with brown-red col... A new kind of catalyst WOBr_4,which can be used in the polymerization of phenylacetylene(PhA),has been synthesized.The obtained polyphenylcetylene(PPhA) using WOBr_4 as catalyst is soluble、fusible、with brown-red colour and has 1831(M n).The analysis of the stucture of PPhA shows that the polymer has cis-transoidal structure,therefore,the reaction mechanism is via complex catalysis. 展开更多
关键词 AS THE STUDYOF synthesis AND characteristics OF POLYPHENYLACETYLENE USING WOBr4AS CATALYST CHEN
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NEW HETEROCYCLIC SYSTEMATIC SYNTHESIS V.THE SYNTHESIS AND CHARACTERISTICS OF 1,3a,5-TRISUBSTITUTED-3a,4,5,11-TETRAHYDRO-1,2,4-OXADIAZOLINO[5,4-d][1,5]BENZODIHETEROPINES
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作者 Hai Tao Wu Sheng JIN 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第2期95-96,共2页
Twenty-seven oxadiazolino[5,4-d][1,5]benzodiheteropine derivatives have been synthesized by the 1,3-dipolar cycloaddition of benzodiheteropines with nitrile oxide 1,3-dipoles,their conformations and the characteristic... Twenty-seven oxadiazolino[5,4-d][1,5]benzodiheteropine derivatives have been synthesized by the 1,3-dipolar cycloaddition of benzodiheteropines with nitrile oxide 1,3-dipoles,their conformations and the characteristics of the newly formed oxadiazoline fused on them have been studied.It has also been found that the mass spectra show characteristic fragmentation patterns. 展开更多
关键词 CI HZ BENZODIHETEROPINES NEW HETEROCYCLIC SYSTEMATIC synthesis V.THE synthesis AND characteristics OF 1 3a 5-TRISUBSTITUTED-3a 4 5 11-TETRAHYDRO-1 2 4-OXADIAZOLINO[5 4-d
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THE SYNTHESIS AND CHARACTERISTICS OF THE COORDINATION COMPOUNDS OF 2-MERCAPTOPYRIDINE-1-OXIDE WITH THE FIPST TRANSITION SERIES METALS
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作者 Bao Lin SONG Zai Sheng LU De Zhong NIU Yang CAO Department of Chemistry,Xuzhou Teacher’s College, Xuzhou 221009Cheng ZENG Coordination Chemistry Institute,Nanjing University,Nanjing 210008 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期117-118,共2页
The stability of the coordination compounds of the first transition series metal ions(Mn(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Cu(Ⅱ)and Zn(Ⅱ))with 2-mercaptopyridine-1- oxide is reported.A coordination compound CoL_2 is synthesized and... The stability of the coordination compounds of the first transition series metal ions(Mn(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Cu(Ⅱ)and Zn(Ⅱ))with 2-mercaptopyridine-1- oxide is reported.A coordination compound CoL_2 is synthesized and characterized for the first time. 展开更多
关键词 In ab CO THE synthesis AND characteristics OF THE COORDINATION COMPOUNDS OF 2-MERCAPTOPYRIDINE-1-OXIDE WITH THE FIPST TRANSITION SERIES METALS
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Soft-chemical synthesis and high-temperature electrochemical characteristics of VO_2
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作者 周科朝 曹笃盟 李志友 《中国有色金属学会会刊:英文版》 EI CSCD 2006年第3期517-521,共5页
VO2 powder was synthesized by a new soft-chemical method using formaldehyde as a reductant. The influences of pyrolysis temperature and time on the phase and morphology of grains were investigated by using thermal gra... VO2 powder was synthesized by a new soft-chemical method using formaldehyde as a reductant. The influences of pyrolysis temperature and time on the phase and morphology of grains were investigated by using thermal gravimeter/differential thermal analysis(TG/DTA), X-ray diffraction(XRD), Fourier transform infrared(FTIR) spectroscopy and scanning electron microscope(SEM). The positive electrode discharge performances of Li-B/LiCl-KCl/VO2 thermal battery at 500 ℃ were studied. The results show that the product is mainly non-crystal when the precursor of VO2 is heated below 300 ℃. VO2(B) appears and transits into VO2(R) irreversibly as the heating temperature rises. The open-circle voltage of VO2 is 2.6 V (vs Li-B), and the initial discharge voltage of 100 mA/cm2 at 500 ℃ is 2.52 V. The specific capacities of 100 mA/cm2 and 200 mA/cm2 at cut-off voltage of 1.4 V are 449 A·s/g and 539 A·s/g, respectively. 展开更多
关键词 VO2粉末 合成 电化学性能 热电池
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SYNTHESIS AND CHARACTERISTIC OF POLYSILANES CONTAINING Si-H BOND 被引量:1
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作者 Ying Kui LI Zhao Hui CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第10期799-800,共2页
Three kinds of polysilanes containing Si-H bond, ■CH_3SiCH_3■_x■CH_3SiH■_y■_n and■PhSiPh■_π■CH_3SiH■_y■CH_3SiCH_3■, have been synthesized. The structures of these copolymers were investigated by IR, ~1H-NM... Three kinds of polysilanes containing Si-H bond, ■CH_3SiCH_3■_x■CH_3SiH■_y■_n and■PhSiPh■_π■CH_3SiH■_y■CH_3SiCH_3■, have been synthesized. The structures of these copolymers were investigated by IR, ~1H-NMR and ^(13)C-NMR and their molecular weights were measured. 展开更多
关键词 Figure synthesis AND characteristIC OF POLYSILANES CONTAINING Si-H BOND Si
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Mechanochemical synthesis of cerium orthophosphate 被引量:1
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作者 A.Matraszek I.Szczygie +1 位作者 L.Macalik J.Hanuza 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第4期598-602,共5页
A facile, simple and rapid preparation method of cerim orthophosphate was presented. The synthesis of low-crystalline CePO4 occurred upon mixing of cerium (Ⅲ) nitrate and sodium phosphate, and was an exchange-type ... A facile, simple and rapid preparation method of cerim orthophosphate was presented. The synthesis of low-crystalline CePO4 occurred upon mixing of cerium (Ⅲ) nitrate and sodium phosphate, and was an exchange-type reaction. The phase composition of the obtained powder was checked by the XRD and FTIR methods, indicating the presence of cerium phosphate. Further investigations on thermal behavior of the synthesized cerium salt had shown that the obtained orthophosphate crystallized at first in rhabdophane-type structure. It converted to monazite (monoclinic symmetry) during heating at the temperatures of above 600℃. Oxidation of Ce3+ to Ce4+ was avoided during the syntheses, as confirmed by the XPS experiments. 展开更多
关键词 cerium phosphate synthesis phase purity characteristics rare earths
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In-Depth Study on Synthesis Load Modeling
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作者 Qi Wang Yong Tang Bing Zhao 《Energy and Power Engineering》 2013年第4期498-504,共7页
Detailed procedures for the modeling of synthesis load models (SLM) of actual power network are presented, then the classification indices based on 1oad characteristics and the principle of load classification are exp... Detailed procedures for the modeling of synthesis load models (SLM) of actual power network are presented, then the classification indices based on 1oad characteristics and the principle of load classification are expounded. Based on the results of general investigation of 220 kV and 330kV substations in China’s power grid, the load characteristics are classified, and detailed load characteristic investigation of selected different kinds of typical substations are carried out. By use of statistical synthesis, the SLM for typical substations, in which the distribution networks are taken into account, are built;and the modeling results are disseminated and applied to whole Chinese power grid. Besides, the load model parameters are evaluated and verified via post-disturbance simulation method. The effectiveness of the built SLM is validated by the fitting of some disturbance incidents. 展开更多
关键词 Chinese Power GRID LOAD characteristics LOAD COMPOSITION LOAD Modeling synthesis LOAD Model (SLM)
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Synthesis,characterization,and antioxidant activity of carboxymethyl chitosan derivatives containing sulfonium salt
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作者 Xueqi SUN Jingjing ZHANG +4 位作者 Yingqi MI Qin MIAO Wenqiang TAN Qing LI Zhanyong GUO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第1期284-295,共12页
To improve the solubility and bioactivity of chitosan,a new class of carboxymethyl chitosan derivatives possessing sulfonium salts was successfully designed and synthesized,including Methyl sulfi de carboxymethyl chit... To improve the solubility and bioactivity of chitosan,a new class of carboxymethyl chitosan derivatives possessing sulfonium salts was successfully designed and synthesized,including Methyl sulfi de carboxymethyl chitosan(MCMCS),Ethyl sulfi de carboxymethyl chitosan(ECMCS),Propyl sulfi de carboxymethyl chitosan(PCMCS),and Butyl sulfi de carboxymethyl chitosan(BCMCS).To determine the structure of the new class of the derivatives,methods of the Fourier transform infrared spectroscopy(FT-IR),^(1)H nuclear magnetic resonance spectrometer(^(1)H NMR),and^(13)C nuclear magnetic resonance spectrometer(^(13)C NMR)were used.Moreover,the antioxidant activity of the derivatives for three types of free radicals,i.e.,hydroxyl radical,superoxide radical,and 1,1-diphenyl-2-picrylhydrazyl(DPPH)radical was evaluated in vitro.In addition,the L929 cells were adopted to test the cytotoxicity of chitosan and its derivatives by CCK-8 assay.The class of the carboxymethyl chitosan derivatives showed a strong scavenging ability against the three free radicals at 1.6 mg/mL,with scavenging rate of over 70%and some up to 100%.At this high rate,the overall cell viability in the toxicity test reached more than 80%,indicating that the synthetic derivative had a little cytotoxicity.The results show that the introduction of carboxymethyl group to chitosan increased the water-solubility of chitosan,and the combination of sulfonate ions with diff erent chain lengths further enhanced the antioxidant activity of chitosan.Therefore,the sulfonium-containing carboxymethyl chitosan derivatives had excellent bioactivity with good application prospects in food,biomedicine,and medical fi elds. 展开更多
关键词 antioxidant activity carboxymethyl chitosan derivative sulfonium salts structural characteristics/synthesis
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Comparison of Surface Characteristics of Mesoporous Titania Prepared in Matrix-Free Solutions and Using Triton X Reverse Micelles
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作者 Polyxeni Paschalidou Charis R. Theocharis 《Materials Sciences and Applications》 2020年第11期715-732,共18页
Titania nanoparticles have been prepared from the precursor compound Ti(OiPr)<sub>4</sub> using Triton X reverse micelles with varying surfactant tail, in a matrix-free aqueous (pH 2) and in non-aqueous ph... Titania nanoparticles have been prepared from the precursor compound Ti(OiPr)<sub>4</sub> using Triton X reverse micelles with varying surfactant tail, in a matrix-free aqueous (pH 2) and in non-aqueous phase (benzyl alcohol and glacial acetic acid, solvothermal method). The importance of this work lies in the further elucidation in the synthetic methodology of preparing well-characterized nanoporous solids. Comparison of the texture characteristics and surface properties of the samples prepared from each technique, was carried out using physicochemical techniques: pXRD, ΒΕΤ/DFT/BJH, FTIR, DRUV-Vis and SEM. The results show that the use of Triton X reverse micelles with varying surfactant size results in TiO<sub>2</sub> solids with adjustable surface characteristics in contrast to matrix-free. Specifically, samples of the latter methods present higher surface area values at lower calcination temperatures but present reduced thermal stability and control of their surface properties. 展开更多
关键词 Titanium Dioxide Surface characteristics MESOPORES Inverse Micelles synthesis
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Synthesis and Performance Evaluation of Anti Temperature and Salt Resistant Polymer Filtrate Reducer
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作者 Zhu Zhu Huaiyuan Long +4 位作者 Dichen Tan Song Wang Zuwen Wang Shunyuan Zhang Yu Deng 《Open Journal of Yangtze Oil and Gas》 2019年第4期248-257,共10页
In the experiment,the filtrate loss of synthetic fluid loss control fluid was recorded in room temperature and high temperature in the composite brine base and sodium chloride brine base slurry,and compared with the f... In the experiment,the filtrate loss of synthetic fluid loss control fluid was recorded in room temperature and high temperature in the composite brine base and sodium chloride brine base slurry,and compared with the filtrate loss before base polymer addition.In this way,the effect of filtration loss and salt resistance and temperature resistance of synthetic polymers were evaluated.The influence of the synthesized polymer on the rheological properties of the composite brine was also evaluated by determining the viscosity of the drilling fluid added to the base slurry and polymer.In the end,the structure of the synthetic polymers was characterized through the infrared spectrum,which initially analyzed through the mechanism of its function in reducing the filter loss.Finally,the products produced according to the recipe are given to the site and added to the two wells to record the drilling fluid performance data. 展开更多
关键词 POLYMER FILTRATE REDUCER RHEOLOGICAL characteristic MONOMER synthesis Drilling Fluid
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水热法合成超细斜发沸石试验研究
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作者 吴照洋 郝小非 +2 位作者 孙启亮 张永兴 权藏玉 《化工矿物与加工》 CAS 2024年第1期15-20,共6页
斜发沸石具有较强的吸附和离子交换能力,在重金属和油污废水去除、制糖、造纸净化、抗菌抗癌药物助剂制备、石油化工催化裂化、国防以及CO_(2)脱除等领域应用广泛。为了获得纯度较高的斜发沸石,以NaOH、KOH、Al(OH)_(3)、Na_(2)O·n... 斜发沸石具有较强的吸附和离子交换能力,在重金属和油污废水去除、制糖、造纸净化、抗菌抗癌药物助剂制备、石油化工催化裂化、国防以及CO_(2)脱除等领域应用广泛。为了获得纯度较高的斜发沸石,以NaOH、KOH、Al(OH)_(3)、Na_(2)O·nSiO_(2)、H_(2)O为原料,采用水热法制备了斜发沸石,并通过XRD和晶面分析,研究了斜发沸石的合成条件,结果表明:合成斜发沸石的最佳条件为n(SiO_(2))/n(Al_(2)O_(3))=11、n(OH-)/n(SiO_(2))=0.55、n(H_(2)O)/n(SiO_(2))=25~55、温度150℃、时间6 d,合成的斜发沸石呈片状结构,特征峰完整,纯度较高,其晶胞组成为Na_(0.36)K_(6.58)[(AlO_(2))6(SiO_(2))_(25.26)]·6.71H_(2)O,n(SiO_(2))/n(Al_(2)O_(3))约为8.5,属中硅铝比沸石。SEM分析结果显示,其粒径在1.3μm以下,表明粒度非常细;其静态水吸附量为34.3%,达到了HG/T 2690-2012《13X分子筛》中的一等品指标要求。研究成果可为高纯度细粒斜发沸石的精准合成提供借鉴。 展开更多
关键词 斜发沸石 水热法 特征峰 硅铝比 合成条件 静态水吸附 晶面分析
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青冈栎原花青素合成基因的鉴定与分析
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作者 曹睿彬 杨俊杰 +2 位作者 罗常莎 姜小龙 徐刚标 《中南林业科技大学学报》 CAS CSCD 北大核心 2024年第5期167-180,共14页
【目的】对青冈栎原花青素(缩合单宁)合成基因进行鉴定及生物信息学分析,可为青冈栎果实资源开发利用和品种改良奠定分子基础。【方法】基于已公布的青冈栎全基因组测序数据,利用生物信息学方法对原花青素合成基因进行鉴定,并分析其蛋... 【目的】对青冈栎原花青素(缩合单宁)合成基因进行鉴定及生物信息学分析,可为青冈栎果实资源开发利用和品种改良奠定分子基础。【方法】基于已公布的青冈栎全基因组测序数据,利用生物信息学方法对原花青素合成基因进行鉴定,并分析其蛋白质序列、染色体定位、种间共线性、基因结构及系统发育关系。【结果】青冈栎中11种原花青素合成基因有42个家族成员,分布在11条染色体上;蛋白质理化性质在具有多拷贝数的QgPAL、QgC4H、Qg4CL、QgF3′H基因家族成员间存在差异;Qg4CL8、Qg4CL14、Qg4CL17、QgF3’H2、QgC4H4蛋白具有2~3个跨膜区域,表明这些蛋白可能在细胞内外信号转导中发挥重要作用;基因家族成员在栎属中进化比较保守,通过栎属古老的全基因组复制及串联重复和片段重复扩张;QgPAL2~QgPAL6和Qg4CL15基因分别与拟南芥中参与原花青素合成的AtPAL1~2和At4CL3聚为同一分支,可能在原花青素生物合成中发挥重要作用;Qg4CL基因家族在系统发育树中进化出新的分支,其家族成员表现出基因结构的多样性,并在4CL基因的高度保守基序中发生氨基酸位点的突变,推测这些基因可能因进化出新功能而被保留下来。【结论】青冈栎原花青素合成基因通过多种复制方式进行扩张,复制基因在栎属中相对保守,在青冈栎中表现出理化性质、蛋白结构和进化模式的多样化。采用生物信息学方法分析了原花青素合成基因的特征和进化模式,这为深入解析栎属植物单宁合成机制奠定了分子基础。 展开更多
关键词 青冈栎 原花青素合成基因 生物信息学 进化特征
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高压直流输电对地电场观测影响特征分析
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作者 李钟慧 王兰炜 +3 位作者 张宇 张兴国 蒋延林 张秀霞 《高电压技术》 EI CAS CSCD 北大核心 2024年第3期1244-1251,I0024,共9页
随着我国“西电东送、南北互供、全国联网”基本战略的实施,多条高压直流输电线路投入运行,对地电场观测造成的干扰愈显突出。为此,总结了全国地电场台站受高压直流输电干扰特征和规律,从统计意义上概括典型干扰形态,包括方波、尖峰和方... 随着我国“西电东送、南北互供、全国联网”基本战略的实施,多条高压直流输电线路投入运行,对地电场观测造成的干扰愈显突出。为此,总结了全国地电场台站受高压直流输电干扰特征和规律,从统计意义上概括典型干扰形态,包括方波、尖峰和方波+尖峰3种,其中以方波为主,占比约65.5%。通过理论推导,结合干扰实例,探讨了不同干扰形态产生的原因及影响机理,认为在近接地极区域表现为方波形态,在线路中心区域表现为尖峰形态,在二者重合区表现为方波和尖峰的组合形态。对比同一线路不同干扰事件,分析了干扰特征和台站与高压线路的相对位置、与接地极距离、影响区域地下结构等因素的关系,为识别和判定此类干扰提供了依据。 展开更多
关键词 HVDC 地电场 干扰特征 接地极 线路合成场
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催化材料的机械化学球磨合成技术及应用研究进展
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作者 陈依琳 王景涛 +2 位作者 吴荣谦 吕毅 刘晓菲 《合成化学》 CAS 2024年第6期587-598,共12页
催化材料的机械化学球磨合成技术由于其简单性、可扩展性和生态友好性而具有一定的发展潜力。此外,该技术合成的材料具有独特的物理和化学特征,例如纳米级结晶度,高缺陷浓度以及系统中组件的紧密相互作用。本文总结了近年来球磨技术在... 催化材料的机械化学球磨合成技术由于其简单性、可扩展性和生态友好性而具有一定的发展潜力。此外,该技术合成的材料具有独特的物理和化学特征,例如纳米级结晶度,高缺陷浓度以及系统中组件的紧密相互作用。本文总结了近年来球磨技术在催化材料合成中的研究进展,强调了通过球磨技术实现的独特材料特性与其催化性能的提高密切相关。最后对球磨技术合成的催化材料的相关应用进行了分类,并对机械球磨技术在催化材料合成中的发展进行了展望。 展开更多
关键词 催化材料 机械化学 球磨合成技术 材料特性 催化性能 催化材料应用
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非预定时标设计要求的球面四杆机构刚体导引综合方法研究
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作者 刘文瑞 司浩天 孙建伟 《机械传动》 北大核心 2024年第3期35-44,共10页
通过对标准安装位置的球面四杆刚体导引机构输出的刚体标线进行处理,发现所得的位姿曲线均为圆弧;通过分析位姿特征曲线的形成机制,揭示了位姿特征圆上相邻特征点对应圆心角与机构连杆转角的内在联系,给出了标准安装位置的球面四杆机构... 通过对标准安装位置的球面四杆刚体导引机构输出的刚体标线进行处理,发现所得的位姿曲线均为圆弧;通过分析位姿特征曲线的形成机制,揭示了位姿特征圆上相邻特征点对应圆心角与机构连杆转角的内在联系,给出了标准安装位置的球面四杆机构设计要求时标补充方法。在此基础上,将该方法推广到一般安装位置球面四杆刚体导引机构中。通过对2维机构安装角度参数和2维机构相对输入角进行优化,实现了一般安装位置的球面四杆刚体导引机构时标的补充,从而借助数值图谱法实现了非预定时标设计要求球面四杆机构刚体导引综合问题的求解。最后,通过算例证明了该时标补充方法的可行性和有效性。 展开更多
关键词 球面四杆机构 位姿特征圆 非预定时标 刚体导引综合
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高温条件下早籼稻灌浆期生理变化与垩白形成的关系
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作者 许金科 谢琴 +4 位作者 魏曼琳 彭仟 苏益 萧浪涛 蔺万煌 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期36-42,126,共8页
为探究高温条件下水稻垩白形成的生理机制,以高垩白性状湘早籼24号(X24)及其来源亲本湘早籼11号(X11,高垩白性状)和湘早籼7号(X7,低垩白性状)为材料进行盆栽试验,在抽穗后第6天移入温室,进行为期15 d的高温处理(27~42℃),以常温处理(23... 为探究高温条件下水稻垩白形成的生理机制,以高垩白性状湘早籼24号(X24)及其来源亲本湘早籼11号(X11,高垩白性状)和湘早籼7号(X7,低垩白性状)为材料进行盆栽试验,在抽穗后第6天移入温室,进行为期15 d的高温处理(27~42℃),以常温处理(23~37℃)作为对照,研究灌浆期高温条件下剑叶净光合速率、籽粒灌浆速率、籽粒直链淀粉含量及淀粉合成相关基因的相对表达量等的变化。结果表明:高温条件下X7、X11和X24的稻米垩白度比常温对照处理的分别增加了2.53、4.82、6.66个百分点;高温造成X11和X24的叶片净光合速率在抽穗后第8、12、16天显著低于常温对照的,而X7的叶片净光合速率在抽穗后第16天反而高于常温对照的;高温条件下水稻在抽穗后第8天灌浆速率加快,并在抽穗后第12天达到最大值,较常温处理的提前了4~8 d;基因相对表达量差异分析表明,X11和X24籽粒淀粉合成相关基因Os SSIIIa、Os AGPSL2和GBSSI在抽穗后第12、16天的表达显著下调,导致籽粒直链淀粉含量降低及垩白度增加。 展开更多
关键词 早籼稻 高温胁迫 垩白 生理特性 淀粉合成
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抗氧化性碳点的设计及其应用
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作者 郑丽丽 张良 《广州化工》 CAS 2024年第4期5-7,共3页
抗氧化性碳点是一类新兴的纳米材料,是碳点的一种分类,它不仅拥有其他碳点具有的生物相容性、稳定性、荧光性、合成简易和易于表面修饰等性质,还具有抗氧化性和清除多种活性氧(ROS)的活性,在生物医学领域引起了广泛关注。本综述主要介... 抗氧化性碳点是一类新兴的纳米材料,是碳点的一种分类,它不仅拥有其他碳点具有的生物相容性、稳定性、荧光性、合成简易和易于表面修饰等性质,还具有抗氧化性和清除多种活性氧(ROS)的活性,在生物医学领域引起了广泛关注。本综述主要介绍抗氧化性碳点的合成方法、特性与机制及其在生物医学领域的应用。 展开更多
关键词 抗氧化性碳点 合成 特性 机制 应用
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Synthesis,Characteristics and Applications of Fibrous Composites with Immobilized Nanomolecular Layers of Ferrocyanides and Phosphates of Some d-Elements
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作者 V.Nesterenko 《复旦学报(自然科学版)》 CAS CSCD 北大核心 2007年第5期702-,共1页
1 Results The general principle of the synthesis of fibrous inorganic ion-exchanging composites, containing the combination of polymer analogous conversion reactions of the fibres and cycles of ion-molecular layering ... 1 Results The general principle of the synthesis of fibrous inorganic ion-exchanging composites, containing the combination of polymer analogous conversion reactions of the fibres and cycles of ion-molecular layering is advanced. Synthesis of thin nanomolecular layers of the acid Ti(Ⅳ) and Zr(Ⅳ) phosphates on surface of the cotton fibres and Cu(Ⅱ) and Fe(Ⅲ) ferrocyanides-on polyacrylonitrile fibres was performed on the basis of this principle. By the method of X-ray analysis it was stated that the forme... 展开更多
关键词 fibrous materials FERROCYANIDES PHOSPHATES synthesis characteristIC
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