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This work aims to present an extended investigation of a new N-MOS device designed in 28 nm FD-SOIUTBB high-k metal gate technology for in-situ heating. Electrical and temperature measurements of different versions of the in-situ heating structure were made at wafer level. Additionally, 3D TCAD electro-thermal simulations were done. Both measurement and simulation results show that the devices are functional and efficient. Such device could be suitable for low and ultra-low temperature design solutions in harsh application environment.

The PbZn 1/3 Nb 2/3 O 3 –PbTiO 3 phase (PZN–PT) prepared by mechanosynthesis exhibits interesting relaxor properties when transformed into nanostructured ceramic by spark plasma sintering. When trying to obtain denser ceramic to enhance physical properties, the PZN–PT phase transformation from perovskite to pyrochlore structure induces the graphite die explosion. An explanation of this phenomenon is based on the reorganization of the lone pairs corresponding to Pb 2+ cations into the large cavities of pyrochlore network, inducing an important cell volume increase, together with the speed of transformation depicted in the light of infinite periodic minimal surfaces describing the perovskite (P-surface) and the pyrochlore (F-surface) networks, respectively.

Cell parameter evolution versus temperature has been established for both V 2 O 5 and MoO 3 , from 15 to 953 and 893 K, respectively. Both oxides preserve their orthorhombic crystal system and their respective space groups Pmmn and Pnma in the whole temperature range. Unusual evolution of the unit cells have been detected in these oxides and proposals are made to follow them based on detailed structural analysis. Three temperature domains have been evidenced for V 2 O 5 marked by breaks at RT and 800 K; for MoO 3 , only two domains are defined below and above 400 K. For each domain the quality of cell parameters and X-ray powder pattern indexing, have been checked by mathematical functions to buttress their coherent evolution within each temperature domain.

The title phase and its homogeneity range ( 0.12 ⩽ x ⩽ 0.18 ) have been established via several controlled solid state reactions at 630 °C. X-ray diffraction and TEM investigations indicate that the diffraction patterns are dominated by diffuse scattering due to heavily faulted layer stacking. After several attempts crystals of better quality were obtained and studied. The structural refinements carried out on one selected crystal from a batch treated at 700 °C and annealed at 600 °C during 4 days presents a formula slightly richer in Mo6+ and V4+, corresponding to x ≈ 0.5 , i.e., Mo1.5V1.5O8. The main structural features are reported and analysed. The structure of these crystals is still affected by stacking defects, but in lower concentrations, leading to twinning phenomena. A detailed investigation by TEM and HREM of crystals corresponding to x = 0.15 confirms the drastic stacking disorder of these materials. Magnetic and electric measurements allow to ascribe the mixed valence formula, Mo6+1+xV5+2−2xV4+xO8 for these various compositions which shows a semi-conducting behaviour with an activation energy for x = 0.15 phase being E a = 0.22 eV .

Single crystals of two cerium complexes, with mixed-ligands oxalate and glycolate, have been prepared in a closed system, at 200 °C for one month: [Ce2(H2O)3](C2O4)2.5(H3C2O3) 1 and Ce2(C2O4)(H3C2O3)4 2. 1 crystallizes in the orthorhombic system, space group Pbca, with a = 13.0090 ( 13 ) A , b = 10.3870 ( 8 ) A , and a = 22.102 ( 3 ) A while 2 crystallizes in the tetragonal system, space group P42/nbc, with a = 11.7030 ( 4 ) A , c = 13.2570 ( 2 ) A . For both complexes, the three-dimensional framework structure is built up by the linkages of the cerium and all the oxygen atoms of oxalate and glycolate ligands. For 2, its structure presents a nice case of two 3D identical sub-lattices, with 2-fold interpenetration. The only link between these two sub-lattices is assumed by strong hydrogen bonds between the hydroxyl function of the glycolate and the oxygen atoms of the oxalate. The schematized framework of 2, including only the cerium atoms, can be compared to that of cooperite (PtS). For 1, the two independent cerium have 9- or 10-fold coordination, forming a distorted monocapped or bicapped square antiprism polyhedron while for 2, the two independent cerium present 8-fold coordination, forming an almost regular dodecahedron. A quite relevant feature of 2 is the complete absence of water. 2 has been extended to other lanthanides ( Ln = Ce … Lu , yttrium included) leading to a family, which has been characterized by infra-red and thermal analysis.

A tin(II) squarate Sn2O(C4O4)(H2O) was synthesized by hydrothermal technique. It crystallizes in the monoclinic system, space group C2/m (no. 12) with lattice parameters a=12.7380(9) A, b=7.9000(3) A, c=8.3490(5) A, β=121.975(3)°, V=712.69(7) A3, Z=4. The crystal structure determined with an R=0.042 factor, consists of [(Sn4O10)(H2O)2] units connected from one another in the [101] and [010] directions via squarate groups to form layers separated by Sn(II) lone pairs. This compound presents the same remarkable structural arrangement as observed in the tin-oxo-fluoride Sn2[Sn2O2F4] inorganic compound with Sn(II) lone pairs E(1) and E(2) concentrated in large rectangular-shape tunnels running along [001] direction.

The electronic and physical properties of Cu2.33V4O11 were characterized by electrical resistivity, magnetic susceptibility and X-ray photoelectron spectroscopy (XPS) measurements and by tight-binding electronic band structure calculations. Attempts to prepare Cu2.33−xV4O11 outside its narrow homogeneity range led to a mixture of Cu2.33V4O11, CuVO3 and β-CuxV2O5. The magnetic susceptibility data show no evidence for a magnetic/structural transition around 300 K. The XPS spectra of Cu2.33V4O11 reveal the presence of mixed valence in both Cu and V. The [Cu+]/[Cu2+] ratio is estimated to be 1.11 from the Cu 2p3/2 peak areas, so [V4+]/[V5+]=0.56 by the charge balance. Our electronic structure calculations suggest that the oxidation state of the Cu ions is +2 in the channels of CuO4 tetrahedra, and +1 in the channels of linear CuO2 and trigonal planar CuO3 units. This predicts that [Cu+]/[Cu2+]=1.33 and [V4+]/[V5+]=0.50, in good agreement with those deduced from the XPS study.

The isostructural compounds of general formula Ax(Mo, V)8O21 (A=K+, Rb+, Cs+) have been synthesized by solid state reaction. They crystallize in the monoclinic system, space group I2/m, Z=2, within the case of K+: a=16.194(2) A, b=13.716(1) A, c=13.716(1) A, and β=90.983(1)°. The three-dimensional network is built up by layers parallel to the (101) plane, constituted of two triple chains of MO6 octahedra (M=Mo, V) associated by edges along the [010] direction and sharing corners in the [ 1 0 1 ] direction, which are connected in the [001] direction via double chains of edge-sharing VO5 square pyramids. This leads to large tunnels where the alkali ions are located. This family provides a new example of a mixed vanadium–molybdenum bronze.

Two forms of copper(II) vanadyl(IV) diselenite CuVO(SeO 3 ) 2 have been synthesized by solid state reaction. The form (A) belongs to the monoclinic system space group P 2 1 / c with a =7.983(1) A, b =8.877(2) A, c =8.437(2) A, and β =100.62(2)°. It is a layered structure built up of CuO 6 and VO 6 octahedra associated, respectively, by pairs via edge sharing which are making [Cu 2 O 10 ] and [V 2 O 10 ] dimers. These dimers are building a layer [CuVO 7 ] n upon which are fixed the selenium (IV) cations. The lone pairs of the selenium (IV) are packed in a double layer perpendicular to the [001] direction. Form (B) crystallizes in the orthorhombic system, space group Pnma with a =7.071(2) A, b =8.223(2) A, and c =9.500(2) A. The structure also exhibits dimers associated via edge and corner sharing along the [100] and [010] directions, which build up layers parallel to the (001) plane; they are held together by Se–O bonds. The connection via V–O–Cu induces a local order that does not respect the three-dimensional order of the network.

Three solid solutions of general composition Bi4−xSbxV2O10, Bi4V4+2−yV5+yO10+y/2, and Bi4V2−zSbzO11have been investigated in the fivefold Bi2O3–V2O5–V2O4–Sb2O3–Sb2O5system. These oxides have been characterized by X-ray diffraction and electron microscopy techniques. Single phases have been isolated for values ranging from 0 tox,z=0.8 andy=2. Single crystals of Bi3.2Sb0.8V2O10, Bi4V2O10.5, and Bi4V1.2Sb0.8O11have been grown and their structures determined by X-ray diffraction methods. The three oxides crystallize in the orthorhombic system, space groups F222, Amam, and Fmmm, respectively. Their structures keep the classical two-dimensional array of Aurivillius-like oxides with (Bi, Sb)–O layers interleaved with (V, Sb)–O sheets. It has been found that Sb3+is introduced into the bismuth layer, due to its similar sterical behavior, by the presence of a 5s2lone pair associated with Sb3+and 6s2associated with Bi3+, whereas Sb5+substitutes for the V5+cation. All of the substitutions carried out mainly act on the vanadium layer, which can accommodate different coordination polyhedra for cations: tetrahedra for V5+, square pyramids and distorted trigonal bipyramids or octahedra for V4+and V5+, and octahedra for Sb5+. This fact can be related to the electrical properties, such as high ionic conduction and ferroelectricity, shown by these types of materials.

The α-Bi4V2O10 structure was determined from Rietveld analysis of X-ray diffraction powder data and electron diffraction microscopy. α-Bi4V2O10 crystallizes in the orthorhombic system, space group Pnma with a = 5.4704(2) A, b = 17.2471(4) A, and c = 14.9219(4) A. This compound, derived from the Aurivillius family, presents a typical layered structure of alternating (Bi2O2)2n and (VO3)2n layers. These layers are built up by corner-sharing VO5 square pyramids in the succession along [010] of three pyramids pointing alternately up and down. Structural relationships between this compound and Bi4V2O10.66 are described, and a structural mechanism that might explain the oxidation at room temperature of α-Bi4V2O10 into Bi4V2O10.66 is proposed.

In order to establish the electrical properties of the new solid solution Bi[Bi 12− x Te x O 14 ]Mo 4− x V 1+ x O 20 , impedance spectroscopy measurements have been performed. They show that the studied materials are good ionic conductors with a conductivity as high as 7.96×10 −3 Ω −1 cm −1 at 750°C for x =1. In parallel, to check the possible phase transitions, a X-ray study between room temperature and 750°C on the compositions x =0, 1 and 2 was undertaken. Any structural changes have been observed in those oxides. The influence of the degree of substitution of Te 4+ and V 5+ for Bi 3+ and Mo 6+ , respectively, has been considered.

A new solid solution of general formula Bi(Bi12−xTexO14)Mo4−xV1+xO20withxup to 2.5 has been prepared by simultaneous substitution of the couple Te4+–V5+for Bi3+–Mo6+in Bi13Mo4VO34. These materials have been studied by X-ray powder diffraction and thermal analysis, showing a structural evolution with changingxvalues. Crystal growth of these phases has been carried out; the single crystals have been studied by transmission electron microscopy and their structure determined by X-ray single crystal diffraction techniques performed for thex=1 andx=2 samples. Both materials crystallize in a monoclinic unit cell, space groupsP2 for Bi(Bi11TeO14)Mo3V2O20(x=1) andP2/cfor Bi(Bi10Te2O14)Mo2V3O20(x=2), with respective unit-cell parametersa=11.704(9),b=5.820(1),c=12.16(1) A,β=100.90(2)° (Z=1) anda=11.642(2),b=5.771(1),c=24.22(1) A,β=101.16(4)° (Z=2). The structures keep the basic framework of “columns” present in the parent oxide Bi(Bi12O14)Mo4VO20; they are built up by infinite (Bi12−xTexO14) columns along the [010] direction and surrounded by independent (Mo, V)O4tetrahedra organized in layers parallel to (100) and (001) planes. The extra Bi cations are located at the intersection of these layers. Thex=1 compound exhibits original structural features due to its acentric structure. The observed structural evolution can be correlated to the different charge balance between columns (Bi12−xTexO14)(8+x)+and tetrahedral environment, as well as to the lower stereochemical activity of the 6s2lone pair of electrons of Bi3+relative to the 5s2electrons of Te4+cation.

The synthesis of new pyrrolo [a]- and [b]acridinones by cyclization of N-arylindoles obtained using ultrasonic irradiations from nitro indole is reported.

The structural determination by X-ray crystallography of the titled N-arylamine 4a, as well as AM1 calculations on a series of derivatives (4b–c, 5a–c), are reported. The compound 4a is monoclinic P21/c with a = 7.656(3), b = 23.655(5), c = 7.686(9) A, β = 112.59(6)°, V = 1285.2(2) A3 and Z = 4. This structure has been used as a template for the building of some others derivatives used for AM1 calculations. The results show that the cyclization position on the aromatic rings, which can lead to two regioisomers, depends on the nature of the benzylic substituants.

A new single phase of composition Bi3NbO7 has been isolated in the binary system Bi2O3–Nb2O5. X-ray single crystal diffraction studies have shown that Bi3NbO7 crystallizes in the cubic system, space group Fm 3 m, with unit-cell parameter a = 5.4788(9) A. The structure has been determined, and the final reliability index is R = 0.027. Bi3NbO7 exhibits a defect fluorite-type structure with 12.5% of anion vacancies and appears to show a disorder in both anionic and cationic lattices. The study by electron diffraction and high resolution electron microscopy has shown the presence of an incommensurate cubic lattice. Bi3NbO7 shows good behavior as an ionic conductor up to 875°C without any phase transition as deduced from impedance measurements.

The synthesis of 9-Methoxy-1-methyl-1H,6H-pyrazolo[4,3-c]carbazole is reported in four steps from 6-nitroindazole. Palladium acetate mediated cyclization gave only the “bent” tetracyclic derivative.

Compounds 2-azido-6H-thiazolo[5,4-a]acridin-11-one 3 and 2-azido-6-butylthiazolo[5,4-a]acridin-11-one 4 have been prepared for the first time. The azido/tetrazole equilibria of the most soluble compound 4 has been studied in six solvents. The resulting tautomeric equilibrium constants have been compared with those of 2-azido-4,5-dimethylthiazole 1 and 2-azidobenzothiazole 2. The rather insoluble NH derivative 3 when dissolved in DMSO contains 66% of tetrazole 3b while the corresponding anion (obtained by adding sodium hydride) is all in the tetrazole 13b form.

Ultrasonics efficiently promotes the Ullmann-Goldberg condensation of 2-halogenobenzoic acids and primary aromatic amines to obtain various N-arylanthranilic acids.

The antimicrobial activity of several new 9-acridinones and 9-thioalkylacridines towards Escherichia coli, Staphylococcus aureus, Mycobacterium smegmatis and Candida albicans was investigated. Minimal inhibitory, bactericidal and fungicidal concentrations were determined using a microplate assay which enabled inhibitory, bactericidal and fungicidal indices to be calculated. These indices facilitated structure/activity relationship studies. DNA-intercalating capability and DNA supercoiling inhibitory effects as well as inhibitory effects on macromolecular synthesis were determined. Results showed that intercalation into DNA, which is the mechanism of action usually postulated for acridines, cannot be correlated with the properties examined. However, inhibition of RNA synthesis may be involved in the antimicrobial activity of the drugs.

Orthorhombic perovskite solid solutions with YMn 1− x Ni x O 3 and YMn 1− x Co x O 3 compositions ( x = 0, 0.05, 0.10, 0.15) have been prepared by mechanosynthesis from a mixture of oxides in a planetary mill. This method allows the use of high-pressure and high-temperature route to be avoided, which is the habitual method to prepare rare-earth manganites with small ionic radius. The high energy supplied by the milling induces the synthesis of the perovskite oxides with a high distortion due to the Jahn–Teller effect. The stability of the structure with temperature is increased with small amounts of Ni proving that the influence of the Jahn–Teller effect is more important than that of the tolerance factor on the stability of the perovskite polymorph. Such stability is not achieved by Co substitution, as this doping is not so efficient in the formation of Mn 4+ , non-Jahn–Teller cations. Magnetic studies were carried out to determine the properties of the materials obtained by this route.

(1994). SYNTHESIS AND COMPETITIVE N- AND O-ALKYLATION OF 10-METHYLPYRIDO[3,2-g]QUINOLINE-4,6-DIONE. Organic Preparations and Procedures International: Vol. 26, No. 4, pp. 473-476.

Aurivillius 's phases exhibit original [Bi2O2]n layers; up to now such phases exist only with bismuth. The aim of this paper is to report new related phase, containing only antimony, which is promissing because its ferroelastic properties. Synthesis, crystal growth and structure determination of the original double oxide Sb2WO6 has been performed. It crystallizes in the triclinic system, space group P1, with a=5.554(1), b=4.941(2), c =9.209(3) A , α=90.05(3), β=96.98(2), γ=90.20(2)°, V =250.8(7) A 3 . TEM and optical microscopy investigations allow to evidence a ferroelastic behaviour at room temperature with a phase transition in the range 300–400°C. The crystal structure of Sb2WO6 is built up by [WO4]n layers of WO6 octahedra sharing corners sandwiched by two [Sb2O2]n layers; it can be described as [WO2Sb2O4]n thick layers held together by weak Sb...O interactions. The antimony atoms exhibit typical 3+1 one sided coordination. Via structural relationships with Sb2O3, VOSb2O4 and Bi2WO6, Sb2WO6 is related with the Aurivillius phases announcing how [Bi2O2]n layers with the shape encountered in red PbO can be formed or distorted.

Synthesis and crystal growth of La(Nb0.70V0.30)O4 with the scheelite type (CaWO4) were performed by direct interaction of La2O3, Nb2O5, V2O5 oxides at 1640°C followed by a slow cooling down to the room temperature. La(Nb0.70V0.30)O4 crystallizes in the tetragonal system, space group I 4 1 a , with a = 5.3283(4) A , c = 11.717(2) A , V = 332.66(5) A 3 , Z = 4. The crystal structure has been refined to R = 0.031 using 324 independant hkl reflections and 15 variable parameters. This structure, isomorphous with LaNbO4 high temperature form, exhibits statistical distribution of Nb5+ and V5+ in the tetrahedron of oxygens part of a stella quadrangula polyhedron. The La atom occupies a site coordinated to 8 oxygen atoms forming a bisdisphenoid. The substitution of vanadium to niobium in LaNbO4 stabilizes this high temperature form with the unusual tetrahedral coordination for niobium 5+.

The cyclization of benzothiazolyl-anthranilic acids always yields ‘bent’ tetracycles. This has been verified in the case of benzothiazol-5-yl derivatives where contrary to a recent literature report, the only products found are thiazolo[4,5-a]acridine derivatives

(I) N-Methyl-2,5,8,11,14,17,20-heptaoxa-25-azatetracyclo[19.7.5.0(24,32),0(26,30)]tritriaconta-1 (29),-21(33),22,24(32),26(30),27-hexaen-31-one trihydrate, C26H33NO8.3H2O, M(r) = 541.6, triclinic, P1BAR, a = 7.389 (1), b = 13.255 (1), c = 14.448 (2) angstrom, alpha = 88.60 (1), beta = 78.58 (1), gamma = 81.48 (1)-degrees, V = 1371.7 (2) angstrom 3, Z = 2, D(x) = 1.31 g cm-3, lambda(Cu K-alpha) = 1.54178 angstrom, mu = 8.68 cm-1, F(000) = 580, T = 291 K, R = 0.047 for 3376 observed reflections. (II) N-Methyl-2,5,8,11,14,17-hexaoxa-22-azatetracylco[16.7.5.0.(21,29).0(23,27)]triaconta-1 (26), 18(30), 19,-21(29),23(27),24-hexaen-28-one, C24H29NO7, M(r) = 443.5, triclinic, P1BAR, a = 8.426 (2), b = 11.420 (2), c = 11.739 (4) angstrom, alpha = 87.20 (3), beta = 79.33 (3), gamma = 77.88 (2)-degrees, V = 1085.3 (5) angstrom 3, Z = 2, D(x) = 1.36 g cm-3, lambda(Mo K-alpha) = 0.71069 angstrom, mu = 1.08 cm-1, F(000) = 472, T = 291 K, R = 0.039 for 3229 observed reflections. In these substituted acridone derivatives one molecule contains both a crown ether moiety with its complexing capabilities and a heterocyclic N atom able to modify these properties. In the two compounds, the crown ether chain is nearly perpendicular to the acridinic skeleton which is planar. In (I) the water molecules take part in hydrogen bonds with the crown ether [O37...O11 = 3.03 (1), O35...O36 = 2.81 (1) angstrom] and with each other [O36...O37 = 2.93 (1), O38...O36 = 2.84 (1), O38...O37 (x + 1, y, z) = 2.89 (1) and O38...O37 (1 - x, 1 - y, 1 - z) = 2.88 (1) angstrom]. The bond lengths suggest partial localization of double bonds in the benzene rings.

Ultrasonics efficiently promotes the Ullmann-Goldberg condensation of 2-halogenobenzoic acids and primary aromatic amines to obtain various N-arylanthranilic acids.

The synthesis of 9-Methoxy-1-methyl-1H,6H-pyrazolo[4,3-c]carbazole is reported in four steps from 6-nitroindazole. Palladium acetate mediated cyclization gave only the “bent” tetracyclic derivative.

The synthesis of new pyrrolo [a]- and [b]acridinones by cyclization of N-arylindoles obtained using ultrasonic irradiations from nitro indole is reported.

Four betaines derived from imidazo[4,5-a], imidazo[5,4-a] and thiazolo[5,4-a]acridine have been prepared in a six step procedure starting from 2-chlorobenzimidazoles and benzothiazoles. The 1H and 13C nmr has been used to characterize the compounds, particularly the orientation of the step leading to the formation of the acridinone ring. The uv-visible spectra of one betaine (wave numbers v in cm−1) shows a linear dependence with Reichardt's ET parameter and a high sensitivity to solvent effects.

The synthesis of new cyclopenta-acridinones and -phenothiazines by cyclization of N-aryl indanes under acidic conditions or via Bernthsen thionation is reported.