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Cr-Ca化学分离方法研究
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作者 汪子辰 孙剑 +2 位作者 李世珍 马健雄 李小伟 《岩石矿物学杂志》 CAS CSCD 北大核心 2024年第4期1066-1072,共7页
多接收电感耦合等离子体质谱仪(MC-ICPMS)测定Ca同位素比值时,Cr元素产生的基质效应会使Ca同位素测试值偏离真实值。利用稀HCl介质和强酸性阳离子交换树脂的传统方法可实现绝大多数元素和Ca的高效分离,但Cr分离率约为90%,分离效果不理... 多接收电感耦合等离子体质谱仪(MC-ICPMS)测定Ca同位素比值时,Cr元素产生的基质效应会使Ca同位素测试值偏离真实值。利用稀HCl介质和强酸性阳离子交换树脂的传统方法可实现绝大多数元素和Ca的高效分离,但Cr分离率约为90%,分离效果不理想。对于超基性岩等高Cr地质样品,Cr/Ca值可高达10。针对这类特殊地质样品的Ca同位素测试,我们研究了Cr-Ca在浓HCl介质中基于AG50W-X12(200-400 mesh)强酸性阳离子交换树脂的淋洗行为。研究结果表明,利用10 mol/L HCl可实现Cr-Ca的高效快速分离,Cr的分离率>99.9%,Ca元素回收率接近100%,同时该方法也可实现K、Mg、Al等元素与Ca的高效快速分离。应用该方法对过柱后Ca单元素溶液和高Cr橄榄岩标样进行Ca同位素测试,其Ca同位素组成(δ^(44/42)Ca)在测试误差范围内与参考值一致,表明该方法适用于高Cr样品的Ca元素分离提纯及同位素测试。 展开更多
关键词 ca同位素 CR 化学分离 MC-ICPMS
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Description of Chemical Abstracts Service
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《Neural Regeneration Research》 SCIE CAS CSCD 2011年第28期2222-2236,共15页
Introduction Chemical Abstracts Service (CAS), a division of the American Chemical Society, is the most authoritative and comprehensive source for chemical information. CAS databases, including CAS REGISTRYSM, the g... Introduction Chemical Abstracts Service (CAS), a division of the American Chemical Society, is the most authoritative and comprehensive source for chemical information. CAS databases, including CAS REGISTRYSM, the gold standard for substance information, are curated and quality-controlled by CAS scientists. Combining these databases with advanced search and analysis technologies, CAS delivers the most complete, cross-linked, and effective digital information environment for scientific research and discovery through such products as SciFinder, STN, STN Express, and STN AnaVistTM, as well as services, such as Science IP. 展开更多
关键词 caS Description of chemical abstracts Service STN OFFICE INVENTOR
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Chemical Abstracts
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《Medicinal Plant》 2017年第1期50-50,共1页
Chemical Abstracts(CA),a reputable international search tool,which involves the widest disciplinary field,collects the most literature types,offers the most searching ways,and has the most prodigious volumes,is edited... Chemical Abstracts(CA),a reputable international search tool,which involves the widest disciplinary field,collects the most literature types,offers the most searching ways,and has the most prodigious volumes,is edited and published by CAS-Chemical Abstracts in the USA.CA has reported more than 10 000 kinds of technology journals,technology reports,meeting papers,academic dissertations,data chronicles,technique reports,new books,and audiovisuals。 展开更多
关键词 caS THAN chemical abstracts MORE
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《心肺血管病杂志》被美国《化学文摘》(Chemical Abstracts,CA)收录一览表
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《心肺血管病杂志》 CAS 2014年第1期141-145,共5页
关键词 首都医科大学附属北京安贞医院 心肺 研究所 血管疾病 血管病 心脏血管疾病 chemical abstracts ca 北京市心肺血管疾病研究所高血压研究室 肺血管病 《化学文摘》 美国 美利坚合众国 北美洲 杂志
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Chemical Abstracts
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《Medicinal Plant》 2017年第2期50-50,共1页
Chemical Abstracts(CA),a reputable international search tool,which involves the widest disciplinary field,collects the most literature types,offers the most searching ways,and has the most prodigious volumes,is edited... Chemical Abstracts(CA),a reputable international search tool,which involves the widest disciplinary field,collects the most literature types,offers the most searching ways,and has the most prodigious volumes,is edited and published by CAS-Chemical Abstracts in the USA. 展开更多
关键词 caS chemical abstracts
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镁合金表面Ca-P涂层的制备及其耐蚀性研究
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作者 蔡宝壮 《新技术新工艺》 2024年第7期46-50,共5页
采用两步阳极氧化和化学沉积结合的方法,在钙/磷比为1.67的溶液中Mg-3wt%Zn-0.8wt%Zr合金表面制备了Ca-P生物涂层。分别采用XRD、SEM、划痕仪和光学显微镜表征分析涂层的物相成分、表面形貌、厚度和结合力,以及通过电化学工作站测定涂... 采用两步阳极氧化和化学沉积结合的方法,在钙/磷比为1.67的溶液中Mg-3wt%Zn-0.8wt%Zr合金表面制备了Ca-P生物涂层。分别采用XRD、SEM、划痕仪和光学显微镜表征分析涂层的物相成分、表面形貌、厚度和结合力,以及通过电化学工作站测定涂层材料的耐腐蚀性能。结果表明:Mg-Zn-Zr合金经过阳极氧化和化学沉积处理生成了Ca-P涂层,主要成分为磷酸氢钙(CaHPO_(4))、二水磷酸氢钙(CaHPO_(4)·2H_(2)O)和磷酸三钙(Ca_(3)(PO_(4))_(2));在沉积时间为48 h的条件下,形成的Ca-P涂层组织形貌致密均匀,与基体的结合力最好,且能使镁合金的腐蚀电位达到-1.181 V,腐蚀速率明显降低,达到了提高镁合金基体耐蚀性的目的。 展开更多
关键词 Mg-Zn-Zr合金 阳极氧化 化学沉积 ca-P涂层 耐蚀性能 制备
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Effect of Gasifying Medium on the Coal Chemical Looping Gasification with CaSO_4 as Oxygen Carrier 被引量:2
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作者 刘永卓 贾伟华 +1 位作者 郭庆杰 Hojung Ryu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第Z1期1208-1214,共7页
The chemical looping gasification uses an oxygen carrier for solid fuel gasification by supplying insufficient lattice oxygen. The effect of gasifying medium on the coal chemical looping gasification with Ca SO4 as ox... The chemical looping gasification uses an oxygen carrier for solid fuel gasification by supplying insufficient lattice oxygen. The effect of gasifying medium on the coal chemical looping gasification with Ca SO4 as oxygen carrier is investigated in this paper. The thermodynamical analysis indicates that the addition of steam and CO2 into the system can reduce the reaction temperature, at which the concentration of syngas reaches its maximum value.Experimental result in thermogravimetric analyzer and a fixed-bed reactor shows that the mixture sample goes through three stages, drying stage, pyrolysis stage and chemical looping gasification stage, with the temperature for three different gaseous media. The peak fitting and isoconversional methods are used to determine the reaction mechanism of the complex reactions in the chemical looping gasification process. It demonstrates that the gasifying medium(steam or CO2) boosts the chemical looping process by reducing the activation energy in the overall reaction and gasification reactions of coal char. However, the mechanism using steam as the gasifying medium differs from that using CO2. With steam as the gasifying medium, parallel reactions occur in the beginning stage, followed by a limiting stage shifting from a kinetic to a diffusion regime. It is opposite to the reaction mechanism with CO2 as the gasifying medium. 展开更多
关键词 chemical LOOPING GASIFIcaTION ca SO4 oxygen caRRIER Reaction mechanism SYNGAS generation
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Laser-induced voltage effects in Ca_3Co_4O_9 thin films on tilted LaAlO_3(001) substrates grown by chemical solution deposition 被引量:1
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作者 王淑芳 陈明敬 +5 位作者 赵书瑞 陈景春 何立平 于威 王江龙 傅广生 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期441-444,共4页
Laser-induced voltage effects in c-axis oriented Ca3Co4O9 thin films have been studied with samples fabricated on 10°tilted LaAIO3 (001) substrates by a simple chemical solution deposition method. An open-circu... Laser-induced voltage effects in c-axis oriented Ca3Co4O9 thin films have been studied with samples fabricated on 10°tilted LaAIO3 (001) substrates by a simple chemical solution deposition method. An open-circuit voltage with a rise time of about 10 ns and full width at half maximum of about 28 ns is detected when the film surface is irradiated by a 308-nm laser pulse with a duration of 25 ns. Besides, opemcircuit voltage signals are also observed when the film surface is irradiated separately by the laser pulses of 532 nm and 1064 nm. The results indicate that Ca3Co4O9 thin films have a great potential application in the wide range photodetctor from the ultraviolet to near infrared regions. 展开更多
关键词 laser-induced voltage ca3Co4O9 thin films chemical solution deposition
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美国《化学文摘》(Chemical Abstract)简介
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《中华神经外科疾病研究杂志》 CAS 2007年第1期94-94,共1页
关键词 《化学文摘》 检索工具 ca 文献量 chemical Abstract 医学文献 药学文献 美国 美利坚合众国 北美洲
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Abstracts Selected from Naihuo Cailiao(Refractories)——A Chinese Language Bimonthly
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《China's Refractories》 CAS 2018年第2期49-54,共6页
Microstructure study of chrome oxide bricks used in cool slurry gasifiers/Gao Zhenxin,Wang Zhanmin, Fan Muxu,Zhu Dexian, Fan Lixia, Zhang Wei, Liu Baikuan//Naihuo Cailiao. - 2017,51 (6) : 401Abstract: For more in-... Microstructure study of chrome oxide bricks used in cool slurry gasifiers/Gao Zhenxin,Wang Zhanmin, Fan Muxu,Zhu Dexian, Fan Lixia, Zhang Wei, Liu Baikuan//Naihuo Cailiao. - 2017,51 (6) : 401Abstract: For more in-depth research on erosion mechanism of re-bonded chrome oxide bricks for coal slurry gasifiers, the chemical composition and microstructure of the bricks before and after use were analyzed by means of X-ray fluorescence spectrometry, and FESEM-EDS. 展开更多
关键词 ca abstracts Selected from Naihuo cailiao REFRACTORIES A Chinese Language Bimonthly
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Chemical Bond Properties and Isomer Shifts of Tl2Ba2Ca2Cu3O10
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作者 Jin-ku Yu Dong-chun Li Fa-ming Gao 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第3期211-213,共3页
Tl2Ba2Ca2Cu3O10 was reported to be a superconductor with a highest transition temperature of 125 K among the homologous series of Tl2Ba2Can-1CunO2n+4. The direct information on the Cu ion site at the atomic level is ... Tl2Ba2Ca2Cu3O10 was reported to be a superconductor with a highest transition temperature of 125 K among the homologous series of Tl2Ba2Can-1CunO2n+4. The direct information on the Cu ion site at the atomic level is important for elucidating the superconductivity mechanism. The local bond properties of Tl2Ba2Ca2Cu3O10 were studied using the average band-gap model. The calculated results show that the covalency of Cu(1)-O bond is 0.561, and the average covalency of Cu(2)-O is 0.296. Mossbauer isomer shifts of 57Fe in Tl2Ba2Ca2Cu3O10 were calculated using the chemical surrounding factor, defined by covalency and electronic polarizability. It is verified that for lower doping, Fe substitute the Cu at the Cu (1) site in forms of Fe^3+ and Fe^4+; for higher doping, Fe^3+ and Fe^4+ ion occupies Cu(1) and Cu(2) site respectively. The studies show that the determination of the correspondence between spectrum components and actual copper sites occupied by MSssbauer nucleus was made easier with the aid of the calculation results of the chemical bond parameters. 展开更多
关键词 SUPERCONDUCTOR Tl2Ba2ca2Cu3O10 chemical bond Mossbauer effect
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The impact of several chemical poisons on the absorbing 45Caby the Arca granosa
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作者 Cai Fulong, Chen Ying and Huang Lingyi Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第3期435-440,共6页
-The impact of several chemical poisons on the Arca granosa absorbing 45Ca was studied. The results showed that the absorption of 45Ca in the blood and the soft tissue by Arca granosa was inhibited by the inorganic co... -The impact of several chemical poisons on the Arca granosa absorbing 45Ca was studied. The results showed that the absorption of 45Ca in the blood and the soft tissue by Arca granosa was inhibited by the inorganic compounds of Cu, Zn, Pd, Cd, Hg and so on, among which the inhibition of Cd was the strongest, next was that of Cu and Hg. But the inhibition of the absorption of 45Ca in the shell of Arca granosa was little. The impact of three kinds of energy metabolism inhibitory substances on the absorption of 45Ca by the Area granosa showed that the absorption was an active transfer process. 展开更多
关键词 ca The impact of several chemical poisons on the absorbing 45caby the Arca granosa
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Chinese Scientists "Photographed" Molecular Picture with Chemical Bond Resolution
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《Bulletin of the Chinese Academy of Sciences》 2001年第1期5-5,共1页
A flagship research project ofthe country during the Ninth Five-Year Plan period (1996-2000), thestudy was conducted under the ae-gis of CAS with financial supportfrom MOST. Remarkable academicprogress has been achiev... A flagship research project ofthe country during the Ninth Five-Year Plan period (1996-2000), thestudy was conducted under the ae-gis of CAS with financial supportfrom MOST. Remarkable academicprogress has been achieved over thepast years, according to the panel. 展开更多
关键词 gis Chinese Scientists Molecular Picture with chemical Bond Resolution Photographed MOST caS
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CA对《学报》英文题目的修改及科技论文题目翻译 被引量:10
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作者 王龙杰 李小玲 +1 位作者 马殷华 黄勇 《广西师范大学学报(自然科学版)》 CAS 北大核心 2006年第3期107-111,共5页
通过比较美国《化学文摘》(Chem ica l A bstracts,简称CA)2001-2004年收录《广西师范大学学报:自然科学版》(简称《学报》)的102篇文摘的题目与发表在《学报》的原英文题目,分析CA修改的原因,并与国际知名刊物英文题目进行比较,找出《... 通过比较美国《化学文摘》(Chem ica l A bstracts,简称CA)2001-2004年收录《广西师范大学学报:自然科学版》(简称《学报》)的102篇文摘的题目与发表在《学报》的原英文题目,分析CA修改的原因,并与国际知名刊物英文题目进行比较,找出《学报》英文题目撰写方面的不足,即冠词误用、study of(on)等泛滥、专业词汇及缩写错误、词性误用、名词单复数误用、介词误用等,并给出提高科技论文英文题目质量的措施。 展开更多
关键词 《广西师范大学学报》 科技论文 英文题目 翻译 化学文摘 收录
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镁合金AZ31表面液相沉积Ca-P生物陶瓷涂层的研究 被引量:18
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作者 张春艳 曾荣昌 +2 位作者 陈君 杨惠 田中青 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2009年第8期1363-1367,共5页
研究了镁合金AZ31经过预钙吸附和阳极氧化预处理后,在Hank’s溶液、Ca(NO3)2和NH4H2PO4混合溶液(简称Ca-P溶液)中制备Ca-P基生物陶瓷涂层的可能性。利用能谱分析仪和X射线衍射仪分析了涂层的化学成分和相组成。结果表明,两种预处... 研究了镁合金AZ31经过预钙吸附和阳极氧化预处理后,在Hank’s溶液、Ca(NO3)2和NH4H2PO4混合溶液(简称Ca-P溶液)中制备Ca-P基生物陶瓷涂层的可能性。利用能谱分析仪和X射线衍射仪分析了涂层的化学成分和相组成。结果表明,两种预处理后的AZ31镁合金在Hank’s溶液中均不能沉积得到涂层。而在Ca—P溶液中浸泡48h后,镁合金表面均沉积了Ca—P涂层。其结晶产物主要为透钙磷石(CaHPO4·2H2O)和少量的Ca(H2PO4)2。预钙吸附处理后镁合金表面形成钙的形核点,在Ca-P溶液中沉积所得的涂层均匀致密,由长、宽20~50μm的片状结晶体组成,结晶体相互咬合交织生长;而阳极氧化处理后的AZ31在Ca—P溶液中沉积所得的涂层则呈竹叶状,且不致密。 展开更多
关键词 镁合金 阳极氧化 化学沉积 ca-P涂层 生物材料
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纳米CaCO_3对硅酸盐水泥水化特性的影响 被引量:18
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作者 王冲 张聪 +2 位作者 刘俊超 李宗阳 尹道道 《硅酸盐通报》 CAS CSCD 北大核心 2016年第3期824-830,共7页
为研究纳米CaCO_3对硅酸盐水泥水化特性的影响,利用微量热仪法测试了不同掺量纳米CaCO_3对硅酸盐水泥水化放热影响,利用差示扫描热分析-热重(DSC-TG)法分析了其水化产物中Ca(OH)_2含量与结合水量,并研究不同掺量纳米CaCO_3对水泥基材料... 为研究纳米CaCO_3对硅酸盐水泥水化特性的影响,利用微量热仪法测试了不同掺量纳米CaCO_3对硅酸盐水泥水化放热影响,利用差示扫描热分析-热重(DSC-TG)法分析了其水化产物中Ca(OH)_2含量与结合水量,并研究不同掺量纳米CaCO_3对水泥基材料力学性能的影响。结果表明,在本试验条件下,纳米CaCO_3的掺入促进了水泥的水化放热速率,水化放热亦随之增加;随着纳米CaCO_3掺量增大,硅酸盐水泥水化生成的Ca(OH)2含量与化学结合水量皆增加;掺入纳米CaCO_3水泥基材料的抗折和抗压强度提高,掺量为1.5%(质量分数)时对水泥基材料的力学性能提高最为显著。研究结果显示纳米CaCO_3加速了硅酸盐水泥的水化。 展开更多
关键词 硅酸盐水泥 纳米碳酸钙 水化 ca(OH)2含量 结合水量
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Trinexapac-ethyl、Prohexad ione-Ca在草坪化学控制中的应用研究 被引量:11
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作者 杨代斌 袁会珠 +2 位作者 覃兆海 何源 王淑芝 《草地学报》 CAS CSCD 2005年第4期304-307,共4页
为探明Trinexapac-ethyl和Prohexadione-Ca用于草坪化学控制的可行性,研究了其对高羊茅(Festuca arundinacea)生长发育的影响.结果显示:使用剂量高于0.095 kg/hm2时, Trinexapac-ethyl对高羊茅具有明显的矮化作用,在0.36 kg/hm2剂量下Pr... 为探明Trinexapac-ethyl和Prohexadione-Ca用于草坪化学控制的可行性,研究了其对高羊茅(Festuca arundinacea)生长发育的影响.结果显示:使用剂量高于0.095 kg/hm2时, Trinexapac-ethyl对高羊茅具有明显的矮化作用,在0.36 kg/hm2剂量下Prohexadione-Ca的抑制率可达95.2%;Trinexapac-ethyl和Prohexadione-Ca都能使植株新增鲜重显著降低,但对新增干重影响很小,Trinexapac-ethyl对植株新增干重无影响;在施用Trinexapac-ethyl的情况下,随着留茬高度的增加新增株高减少,合理留茬高度为4~6 cm;Trinexapac-ethyl和Prohexadione-Ca可以有效降低株高,从而减少草坪修剪次数. 展开更多
关键词 Trinexapac-ethyl Prohexadione-ca 化学控制 生长抑制剂 草坪草 高羊茅
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煤化学链燃烧中CaSO_4/膨润土复合载氧体的反应特性 被引量:5
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作者 贾伟华 刘永卓 +2 位作者 胡修德 杨明明 郭庆杰 《化学反应工程与工艺》 CAS CSCD 北大核心 2014年第1期35-40,共6页
以工业级硫酸钙和膨润土为原料,通过机械混合法,制备了具有高强度的钙基载氧体。同时,在小型高温流化床上,以水蒸气为气化剂,考察了不同温度下载氧体与煤的反应活性和循环反应性。实验结果表明, CaSO4/膨润土载氧体具有高的机械... 以工业级硫酸钙和膨润土为原料,通过机械混合法,制备了具有高强度的钙基载氧体。同时,在小型高温流化床上,以水蒸气为气化剂,考察了不同温度下载氧体与煤的反应活性和循环反应性。实验结果表明, CaSO4/膨润土载氧体具有高的机械强度。在820~900℃,载氧体与煤反应性随温度升高而增强。反应温度为900℃时,气体产物中CO2平均浓度为89.52%,基本不存在CO和CH4。随着还原/氧化循环数增加,载氧体表现良好的反应性,7次循环反应后,碳转化率在70%以上,CO2的平均体积含量保持在80%左右。X射线衍射分析表明,载氧体的还原产物为CaS,未生成CaO副产物。 展开更多
关键词 钙基复合载氧体 化学链燃烧 循环反应性
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化学分析法精确测定羟基磷灰石中的Ca和P含量 被引量:5
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作者 王志锋 宋邦才 张军 《硅酸盐通报》 CAS CSCD 北大核心 2007年第1期186-189,共4页
分别采用改进的EDTA络合滴定法和高锰酸钾氧化返滴法精确测定了羟基磷灰石(HA)等物质中的钙含量,通过对比实验、精密度实验和加标回收实验对基准碳酸钙、分析纯磷酸三钙、分析纯磷酸氢钙及合成的羟基磷灰石中的钙含量进行了测定,对结果... 分别采用改进的EDTA络合滴定法和高锰酸钾氧化返滴法精确测定了羟基磷灰石(HA)等物质中的钙含量,通过对比实验、精密度实验和加标回收实验对基准碳酸钙、分析纯磷酸三钙、分析纯磷酸氢钙及合成的羟基磷灰石中的钙含量进行了测定,对结果的标准偏差、相对标准偏差及回收率做了比较分析和讨论。结果表明,两种方法测定结果相当吻合,改进的EDTA法比高锰酸钾法更快速、简便,能够满足钙磷酸盐中钙含量的准确测定。钙含量测定的最大标准偏差和相对标准偏差分别为0.057和0.15%。同时,采用磷钼酸喹啉容量法测定了样品中的磷含量。 展开更多
关键词 羟基磷灰石 钙含量 磷含量 化学分析 测定
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钢液用Fe-Si、Ba-Ca-Si作发热剂的实验研究 被引量:6
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作者 乐可襄 董元箎 +2 位作者 王海川 宋宇宾 杨世权 《钢铁》 CAS CSCD 北大核心 1996年第S1期32-36,共5页
采用Fe-Si、Ba-Ca-Si作发热剂,对钢液进行了化学升热法的实验研究。主要测定了升温速度、升温值和热效率,讨论了发热剂加入量过剩指数、氧流量、供氩强度和枪位对升温效果的影响。
关键词 炼钢 精炼 化学升热法 FE-SI BA-ca-SI
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