International Journal of Inorganic Materials最新文献_第9页

Polyacrylamide gel: an efficient tool for easy synthesis of multicomponent oxide precursors of ceramics and glasses 聚丙烯酰胺凝胶:一种易于合成陶瓷和玻璃多组分氧化物前驱体的有效工具

International Journal of Inorganic Materials Pub Date : 2001-11-01 DOI: 10.1016/S1466-6049(01)00188-X

André Douy

{"title":"Polyacrylamide gel: an efficient tool for easy synthesis of multicomponent oxide precursors of ceramics and glasses","authors":"André Douy","doi":"10.1016/S1466-6049(01)00188-X","DOIUrl":"10.1016/S1466-6049(01)00188-X","url":null,"abstract":"<div>The combination of citrate complexation in aqueous chemistry with the steric entrapment effect of an auxiliary organic gel affords the possibility of easy and rapid synthesis of high quality multicomponent oxide powders. Stable solutions of strongly chelated cations are obtained by controlling the amount of ligand and the pH. These solutions are then easily gelled by in situ formation of polyacrylamide gel. This hydrous gel is directly decomposed by thermal treatment, resulting in fine and nanoscale powders. The polyacrylamide gel makes the citrate process easier and more rapid. The chemical homogeneity of the powders, usually high for the citrate process, may be improved by the steric effect of the organic gel. The process, routinely used for hundreds of preparations is illustrated by the synthesis of four compounds as examples. Nearly single-phase calcium hexaaluminate CaAl12O19 is obtained after heat treatment at 1100°C for 1 h. Pure lanthanum manganite La0.8Sr0.2MnO3 and barium zirconate BaZrO3 are formed at 650 and 1000°C, respectively. The synthesis of anorthite CaAl2Si2O8 is an example of the use of this process for silicates or aluminosilicates in aqueous chemistry without citrate chelation. The amorphous precursor crystallises at 1000°C into hexagonal anorthite before transforming into the stable triclinic form. The steric entrapment effect of the polyacrylamide gel is advantageous for aqueous chemical processes, and in the same way, the same concept may be used for other organic gels in organic media.</div>","PeriodicalId":100700,"journal":{"name":"International Journal of Inorganic Materials","volume":"3 7","pages":"Pages 699-707"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1466-6049(01)00188-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84531205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 87

Ternary lithium nitridocuprates, Li3−x−yCuxN: crystal growth, bulk synthesis, structure and magnetic properties 三元氮化锂，Li3−x−yCuxN:晶体生长、体合成、结构和磁性能

International Journal of Inorganic Materials Pub Date : 2001-11-01 DOI: 10.1016/S1466-6049(01)00081-2

Alexandra G. Gordon , Duncan H. Gregory , Alexander J. Blake , David P. Weston , Martin O. Jones

{"title":"Ternary lithium nitridocuprates, Li3−x−yCuxN: crystal growth, bulk synthesis, structure and magnetic properties","authors":"Alexandra G. Gordon , Duncan H. Gregory , Alexander J. Blake , David P. Weston , Martin O. Jones","doi":"10.1016/S1466-6049(01)00081-2","DOIUrl":"10.1016/S1466-6049(01)00081-2","url":null,"abstract":"<div>Systematic studies within the ternary Li–Cu–N system have examined the effects of varying starting materials, transition metal stoichiometry, reaction temperature/duration and cooling rate on crystal growth and bulk phase formation of ternary nitridocuprates. Resulting lithium transition metal compounds, Li3−x−y□yCuxN (□=Li vacancy), have been characterised by single crystal and powder XRD. The maximum copper substituent level (x≈0.45) and vacancy level, y, appear insensitive to reaction temperature. Both vacancies and copper are disordered with Li when reaction mixtures are quenched (α-Li3N-type: P6/mmm, a≈3.7 Å, c≈3.8 Å, Z=1), whereas evidence of copper and/or vacancy ordering exists on slow cooling. Morphology of crystallites has been evaluated by SEM and magnetic properties have been investigated using squid magnetometry. Magnetic data show compounds exhibit temperature dependent paramagnetism in contrast to the parent nitride, Li3N.</div>","PeriodicalId":100700,"journal":{"name":"International Journal of Inorganic Materials","volume":"3 7","pages":"Pages 973-981"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1466-6049(01)00081-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90996735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 17

Study of (Sr, Pb)TiO3 ceramics on dielectric and physical properties (Sr, Pb)TiO3陶瓷介电性能和物理性能的研究

International Journal of Inorganic Materials Pub Date : 2001-11-01 DOI: 10.1016/S1466-6049(01)00187-8

Yoshitaka Somiya, Amar S Bhalla, L.Eric Cross

引用次数: 120

Electrical behaviour of the system La1.33NaxMnxTi2−xO6 (x=0.66, 0.55 and 0.44) La1.33NaxMnxTi2−xO6体系(x=0.66, 0.55和0.44)的电学行为

International Journal of Inorganic Materials Pub Date : 2001-11-01 DOI: 10.1016/S1466-6049(01)00195-7

A.I Ruiz , M.L López , C Pico , M.L Veiga , T.A Ezquerra

引用次数: 2

Synthesis, characterization and thermodynamics of the reaction of calcium methylphosphonate with n-alkylmonoamines 甲基膦酸钙与正烷基单胺反应的合成、表征及热力学研究

International Journal of Inorganic Materials Pub Date : 2001-11-01 DOI: 10.1016/S1466-6049(01)00089-7

Cicero B.A Lima, Claudio Airoldi

{"title":"Synthesis, characterization and thermodynamics of the reaction of calcium methylphosphonate with n-alkylmonoamines","authors":"Cicero B.A Lima, Claudio Airoldi","doi":"10.1016/S1466-6049(01)00089-7","DOIUrl":"10.1016/S1466-6049(01)00089-7","url":null,"abstract":"<div>Lamellar crystalline calcium methylphosphonate, Ca[(HO)O2PCH3]2.H2O reacted with a series of n-monoalkylamines to yield the compounds Ca[(HO)O2PCH3]2·xH2N(CH2)nCH3·(1−x)H2O (n=0–4). Intense bands of the phosphonate group in the 1095–995 cm−1 region in the infrared spectrum were detected. X-ray diffraction patterns showed a sharp and intense peak with an interlamellar distance of 907 pm. 31P NMR spectrum gave a peak at 27.38 ppm for phosphonate groups. On heating methylphosphonate water molecules, organic moiety and P2O5 were released to yield a residue of pyrophosphate. The aminated compound presented the same sequence of mass loss, with amine being lost in the first stage. 3C NMR spectrum presented peaks at 15 and 17 ppm for methylphosphonate groups. The original crystallinity of the compound is disturbed by the reaction with the n-alkylmonoamine, giving constant interlamellar distance. The energetic effect caused by amine was determined through reaction-solution calorimetry in the solid–liquid interface from aqueous solution. The thermodynamic data showed that the system is favored by enthalpy, Gibbs free energy, and entropy values.</div>","PeriodicalId":100700,"journal":{"name":"International Journal of Inorganic Materials","volume":"3 7","pages":"Pages 907-914"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1466-6049(01)00089-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88078366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 21

Homogeneous precipitation and thermal phase transformation of mullite ceramic precursor 莫来石陶瓷前驱体的均匀析出与热相变

International Journal of Inorganic Materials Pub Date : 2001-11-01 DOI: 10.1016/S1466-6049(01)00166-0

Sugita Satoshi, César Contreras , Héctor Juárez , Alberto Aguilera , Juan Serrato

{"title":"Homogeneous precipitation and thermal phase transformation of mullite ceramic precursor","authors":"Sugita Satoshi, César Contreras , Héctor Juárez , Alberto Aguilera , Juan Serrato","doi":"10.1016/S1466-6049(01)00166-0","DOIUrl":"10.1016/S1466-6049(01)00166-0","url":null,"abstract":"<div>A fine pure mullite powder was prepared by homogeneous precipitation, mixing a fumed silica suspension in water and aqueous solutions of ammonium bisulphite and aluminium sulphate. This method produced a nanocomposite like structure, consisting of a fumed silica core coated with a thin layer of basic aluminium sulphate. The thermal transformation sequence of this mullite precursor was studied in this work in detail by means of scanning electron microscopy, X-ray powder diffraction technique, BET, thermal analysis (DTA and TG), and infrared spectroscopy, dilatometry and particle size distribution analysis. This nanocomposite lost water accompanied by a shrinkage at temperatures lower than 400°C. The sulphate ion elimination occurred at a temperature range of 500–850°C. Although most of the sulphate ion was eliminated, the powder was still amorphous at 800°C. The γ-Al2O3 was formed at 850°C increasing the particle size by the pyroexpansion process (eliminating sulphur trioxide gas). A spinel phase and traces of crystalline mullite were formed at 950°C. A fine mullite whisker was observed in the samples calcined at 1000–1100°C. A total transformation to mullite required temperatures higher than 1250°C. Grain growth occurred at these temperatures at the same time.</div>","PeriodicalId":100700,"journal":{"name":"International Journal of Inorganic Materials","volume":"3 7","pages":"Pages 625-632"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1466-6049(01)00166-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83544302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 24

Thermal solid–solid interaction and physicochemical properties of CuO–Fe2O3 system CuO-Fe2O3体系固固热相互作用及理化性质研究

International Journal of Inorganic Materials Pub Date : 2001-11-01 DOI: 10.1016/S1466-6049(01)00165-9

W.M. Shaheen , A.A. Ali

{"title":"Thermal solid–solid interaction and physicochemical properties of CuO–Fe2O3 system","authors":"W.M. Shaheen , A.A. Ali","doi":"10.1016/S1466-6049(01)00165-9","DOIUrl":"10.1016/S1466-6049(01)00165-9","url":null,"abstract":"<div>A series of single and mixed oxides of CuO–Fe2O3 was prepared by thermal treatment of pure and mixed copper and ferric nitrate solids at 350–1000°C. The thermal behaviour of the single and binary salts has been studied using the thermal analysis (TG-DTG) technique. The thermal products were characterised using the X-ray diffraction analysis. The results revealed that copper and ferric nitrates decomposed to CuO and Fe2O3 at about 400°C, respectively, in the Cu–Fe mixtures. The presence of ferric oxide in the mixture prevents the reduction process of CuO to Cu2O. Crystalline copper ferrite phase was detected at 750 and 1000°C as a result of solid–solid interaction between CuO and Fe2O3. The presence of excess of CuO in the mixture stimulates the formation of well crystalline copper ferrite phase while excess of Fe2O3 hinders the previous process. The catalytic activity of the obtained pure and mixed oxides was measured using the decomposition of hydrogen peroxide at 30–50°C. It was found that the mixed oxide solids have catalytic activity higher than single oxides preheated at 350 and 550°C. The rise in precalcination temperature to 750 and 1000°C brought about a drastic decrease in the activity of mixed solids because of formation of copper ferrite phase and/or sintering process.</div>","PeriodicalId":100700,"journal":{"name":"International Journal of Inorganic Materials","volume":"3 7","pages":"Pages 1073-1081"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1466-6049(01)00165-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73079427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 34

Synthesis and crystal structure of three MM′B9O15 borates (M=Ba, Sr and M′=Li; M=Ba and M′=Na) 三种MM ' b9o15硼酸盐(M=Ba, Sr和M ' =Li)的合成及晶体结构M=Ba, M ' =Na)

International Journal of Inorganic Materials Pub Date : 2001-11-01 DOI: 10.1016/S1466-6049(01)00078-2

N Penin , L Seguin , M Touboul , G Nowogrocki

{"title":"Synthesis and crystal structure of three MM′B9O15 borates (M=Ba, Sr and M′=Li; M=Ba and M′=Na)","authors":"N Penin , L Seguin , M Touboul , G Nowogrocki","doi":"10.1016/S1466-6049(01)00078-2","DOIUrl":"10.1016/S1466-6049(01)00078-2","url":null,"abstract":"<div>The compounds BaLiB9O15 (BaLi), BaNaB9O15 (BaNa) and SrLiB9O15 (SrLi) have been synthesised, and their structure determined by single crystal X-ray diffraction methods. Each borate crystallises with six formula units in the R3c non-centrosymmetric space group. Cell parameters are: a=11.0223(19) Å, c=17.106(4) Å, and V=1799.8(6) Å3 for the (BaLi) compound; a=11.0933(15) Å, c=17.392(3) Å, and V=1853.5(5) Å3 for the (BaNa) compound; a=10.6129(9) Å, c=17.555(2) Å, and V=1712.4(3) Å3 for (SrLi) compound. The borate anion is characterised by a three-dimensional framework built up from [B3O7] rings; its shorthand notation is 3: ∞3 (2△+T), where △ is a BO3 triangle and T is a BO4 tetrahedron. In these three compounds, the alkaline earth (Ba, Sr) and the alkaline (Li, Na) ions occupy alternate sites in the channels along the c axis; however, their oxygenated environment is different. In (BaNa) and (SrLi), the [BaO9] and [SrO9] form tricapped trigonal prisms and [NaO6] and [LiO6] trigonal antiprisms whereas in (BaLi), [BaO12] forms an irregular icosahedron and there are only three oxygen atoms in the neighboring of lithium ion.</div>","PeriodicalId":100700,"journal":{"name":"International Journal of Inorganic Materials","volume":"3 7","pages":"Pages 1015-1023"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1466-6049(01)00078-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75063323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 58

(CN4H7)2·Zn3(HPO3)4, a three-dimensional framework zincophosphite: an example of template–template co-operation? (CN4H7)2·Zn3(HPO3)4，三维框架锌磷酸酯:模板-模板合作的一个例子?

International Journal of Inorganic Materials Pub Date : 2001-11-01 DOI: 10.1016/S1466-6049(01)00076-9

William T.A Harrison , Mark L.F Phillips , Tina M Nenoff

{"title":"(CN4H7)2·Zn3(HPO3)4, a three-dimensional framework zincophosphite: an example of template–template co-operation?","authors":"William T.A Harrison , Mark L.F Phillips , Tina M Nenoff","doi":"10.1016/S1466-6049(01)00076-9","DOIUrl":"10.1016/S1466-6049(01)00076-9","url":null,"abstract":"<div>The hydrothermal synthesis and single crystal structure of (CN4H7)2·Zn3(HPO3)4 are reported. This phase is built up from a network of vertex-linked ZnO4 and HPO3 building units encapsulating the extra-framework animoguanidinium cations. A new type of three-dimensional network for the inorganic component of the structure arises, which contains polyhedral 4-, 6-, 8-, 12- and 16-rings. There are close (∼3.6 Å), side-on, template–template contacts similar to those seen between pairs of guanidinium cations in molecular compounds. Crystal data: (CN4H7)2·Zn3(HPO3)4, Mr=666.30, monoclinic, space group P21/n (No. 14), a=10.2589 (4) Å, b=29.5851 (12) Å, c=13.7578 (5) Å, β=103.303 (1)°, V=4063.6 (5) Å3, Z=8, T=298 (2) K, R(F)=0.0399, wR(F2)=0.0792.</div>","PeriodicalId":100700,"journal":{"name":"International Journal of Inorganic Materials","volume":"3 7","pages":"Pages 1033-1038"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1466-6049(01)00076-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75180340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 42

Kinetics of solid state reaction between zirconium and copper(I) chloride 锆与氯化铜(I)固相反应动力学

International Journal of Inorganic Materials Pub Date : 2001-11-01 DOI: 10.1016/S1466-6049(01)00179-9

B. Gillot , H. Souha , M. Radid

引用次数: 2