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In the present study, a C/SiFeN(O)-based ceramic paper with in situ generated hierarchical micro/nano-morphology was prepared upon thermal treatment of a cellulose-base paper surface-modified with a polymeric single-source precursor prepared from perhydropolysilazane (PHPS) and iron(II) acetylacetonate (Fe(acac) 2 ). The ammonolysis at 1000 °C of the paper/precursor hybrid materials leads to a C/SiFeN(O)-based ceramic paper which exhibits the same morphology as that of the cellulose paper. Subsequent annealing of the ceramic paper in nitrogen atmosphere at temperatures from 1200 to 1400 °C results in the in-situ generation of ultra-long silicon nitride nanowires with aspect ratios in the range of 10 3 on the surface and in the macropores of the ceramic paper. The nanowires exhibit round Fe 3 Si tips at the end, indicating that the growth occurred via iron-catalyzed VLS (vapor-liquid-solid) mechanism. The combination of single-source precursor, porous template and in situ VLS growth of 1D nanostructures provides a convenient one-pot synthesis approach to produce ceramic nanocomposites with hierarchical morphologies. [ABSTRACT FROM AUTHOR]

This study reports a novel and efficient method for the synthesis of the first reported novel class of thiopyrazoles and their corresponding thioglycosides. These series of compounds were designed through the reaction of hydrazine derivatives with sodium dithiolate salt2in EtOH at ambient temperature to give the corresponding sodium 5-amino-4-cyano-1H-pyrazole-3-thiolates4a-d. The latter compounds were treated with α-acetobromoglucose6aand α-acetobromogalactose6bin DMF at ambient temperature to give in an excellent yields the corresponding pyrazoleS-glycosides7a-h. Ammonolysis of the pyrazole thioglycosides7a-hafforded the corresponding free thioglycosides8a-h. [ABSTRACT FROM PUBLISHER]

Nanocrystalline Gd2O2NCN ( P 3 m1, crystallite size 30-40 nm) was synthesized upon ammonolysis of bis[ [(N-carboxymethyl,N-carboxy-κO-methyl)amino-κN]-ethyl]-glycinato(3-)-κN,κO]gadolinium(III) (diethylenetriamine pentaacetic acid gadolinium(III) dihydrogen salt or gadopentetic acid, Gd-H2DTPA hereafter) at 900 °C. The conversion of Gd-H2DTPA into Gd2O2NCN takes place in several steps, probably via transient formation of iminodiacetate-, glycinate-, and carbamate-containing complexes of Gd. Thermal treatment in air of Gd-H2DTPA at 750 and 1300 °C delivers nanocrystalline bixbyite-type Gd2O3 ( Ia 3, crystallite size 30-70 nm); in an argon or nitrogen atmosphere the formation of monoclinic Gd2O3 ( C2/ m) was observed at 1300 °C. The synthesized Gd2O2NCN converts upon thermal treatment in air, nitrogen, or argon atmosphere into monoclinic Gd2O3 ( C2/m). In ammonia atmosphere, Gd2O2NCN seems to be stable against decomposition, even upon prolonged exposure to 1000 °C. This study indicates that Gd-H2DTPA may be a robust, low-cost, and flexible precursor for nanoscaled Gd-based nanopowders. Moreover, precursor approaches based on metal complexes using H5DTPA as a ligand are suggested as promising access pathways towards nanocrystalline materials in the M/O/C/N system. [ABSTRACT FROM AUTHOR]

We report the preparation and electrochemical properties of Na 3 V(PO 3 ) 3 N made by ammonolysis. Na 3 V(PO 3 ) 3 N is reversibly oxidized to Na 2 V(PO 3 ) 3 N at high voltage (4.0 V vs . Na + /Na 0 and 4.1 V vs . Li + /Li 0 ) with an unusually small difference in the insertion/extraction voltage between both alkali metal reference electrodes. In both cases, the voltage hysteresis is extremely small (~ 0.035 V vs . sodium and ~ 0.065 V vs . lithium), which suggests facile migration of alkali cations within the structure. Further oxidation to NaV(PO 3 ) 3 N is predicted to occur beyond the voltage stability window of the electrolytes. [ABSTRACT FROM AUTHOR]

Polyhalogenated benzotrichlorides (pentafluoro-, chlorotetrafluoro-, chlorotrifluoro-, and tetrafluorobenzotrichlorides) undergo one-pot ammonolysis + aminodefluorination by the action of anhydrous ammonia to form mono- and diamino derivatives of polyhalobenzonitriles. For the substrates comprising halogen at the para -position, the ammonolysis of the CCl 3 group and the first aminodefluorination occur simultaneously in the temperature range from −33 to 5 °C. The temperature of introducing the second NH 2 group is higher by 60–100 °C, whereby conditions were found for the selective synthesis of mono- and diaminopolyhalobenzonitriles. The use of anhydrous ammonia as a reagent and a solvent minimizes side reactions and simplifies an isolation of the high purity products. [ABSTRACT FROM AUTHOR]

A series of ammonia treated Mo/Activated Carbon (AC) catalysts were synthesized by wet impregnation method by nominal incorporation of 5, 10 and 15 wt% of molybdenum. The calcined catalysts ( $$500{^{\circ }}\hbox {C}$$ , 4 h, $$\hbox {N}_{2}$$ flow) were subjected to a stepwise ammonia treatment at temperatures from 25 up to $$700{^{\circ }}\hbox {C}$$ . This work reports for the first time, ammonia treated different loadings of Mo on DARCO mesoporous activated carbon for CO hydrogenation reaction. These catalysts were tested in the reaction temperature range of 250-325 $${^{\circ }}\hbox {C}$$ , 7 MPa and 12000/h (GHSV for reactor volume 0.5 mL). At $$250{^{\circ }}\hbox {C}$$ , all the catalysts showed total oxygenate selectivity of $$\sim $$ 50%, mainly methanol. At $$325{^{\circ }}\hbox {C}$$ , total oxygenate selectivity of 16.5% with 18% CO conversion was obtained on 10Mo-N/AC. The result of alcohol distribution revealed high selectivity to propanol (39%) over methanol (34%) at $$325{^{\circ }}\hbox {C}$$ on 10Mo-N/AC which highlights its unique catalytic behavior in CO hydrogenation. Further, $$\hbox {10MoO}_{3}/\hbox {AC}$$ catalyst, with no treatment of ammonia, showed only 4% of CO conversion with 96% hydrocarbon selectivity. Only 0.5% of CO conversion was observed on AC itself at $$325{^{\circ }}\hbox {C}$$ . The improved oxygenates selectivity on 10Mo-N/AC was associated with $$\hbox {Mo}^{\updelta +}$$ sites on AC generated via ammonolysis. Graphical Abstract: SYNOPSIS A series of ammonia treated Mo/Activated Carbon (AC) catalysts were synthesized by wet impregnation method by nominal incorporation of 5, 10 and 15 wt% of molybdenum. These catalysts were tested for CO hydrogenation reaction at 250-325 $${^{\circ }}\hbox {C}$$ , 7 MPa and 12,000/h (GHSV) for the first time. At $$325{^{\circ }}\hbox {C}$$ , total oxygenate selectivity of 16.5% was observed on 10Mo-N/AC. [ABSTRACT FROM AUTHOR]

Thin films fabricated by spin coating of the gels obtained from tantalum (V) ethoxide precursor were subjected to ammonolysis at 500 °C. Cu-incorporated gels obtained from the same precursor were also spin coated and calcined at 500 °C to give thin films. The optical, structural and photocatalytic properties and their dependence on the thicknesses of these thin films were compared with undoped TaO thin films fabricated by the same precursor. All the thin films were deposited on glass substrate by spin coating with the thicknesses ( d) ranging from 150 to 300 nm. The structure and optical properties of the films were investigated by X-ray diffraction, X-ray photoelectron spectroscopy, spectroscopic ellipsometry, atomic force microscopy, and UV-Vis-NIR spectroscopy. The experimental results insinuated that not only ammonolysis at 500 °C and Cu-doping drastically affect the properties of tanatala films but a variation in their thickness also has significant influence. Small intensity peaks of TaON phase were also detected by X-ray diffraction in the ammonolysed thin films. XPS analysis showed that nitrogen and copper were successfully incorporated in to the TaO lattice of the respective films. Lower refractive indices and significant narrowing of band gaps (E) (i.e. form 3.49 to 3.27 eV for N doped and to 2.92 eV for Cu doped) were observed as compared to the undoped and oxygen-calcined TaO films. Photocatalytic efficiency of the films was demonstrated by photo-degradation of methylene blue (MB) under UV irradiation. Maximum MB degradation of 86.87% was observed for the Cu-doped TaO film, while 72.01% of MB concentration was degraded by N-doped TaO film as compared to only 59.12% MB degradation exhibited by undoped TaO thin film. [ABSTRACT FROM AUTHOR]

In this work, the direct synthesis of materials formed by a network of Al, P, N and O atoms (AlPON) from the ammonolysis of P and N molecular precursors in an ionic liquid is reported. The as-made samples can be treated under ammonia at high temperature to remove the ionic liquid retained after synthesis. The resulting amorphous materials have high porosity and surface area. The P atoms of the skeleton are involved in single and double bonds with N atoms, whereas bridged NH and terminal P-NH 2 groups are also present. However, no evidence for Al N bonds has been found. It has been shown by pyrrole adsorption that these materials exhibit basic properties, showing a basic strength higher than that of Si N materials, but weaker than hydrotalcites. Nevertheless, they are active and very selective catalysts for the Michael addition reaction between malononitrile and chalcone. [ABSTRACT FROM AUTHOR]

This study aims to propose a biorefinery pretreatment technology for the bioconversion of sugarcane bagasse (SB) into biofuels and N-fertilizers. Performance of diluted acid (DA), aqueous ammonia (AA), oxidate ammonolysis (OA) and the combined DA with AA or OA were compared in SB pretreatment by enzymatic hydrolysis, structural characterization and acetone-butanol-ethanol (ABE) fermentation. Results indicated that DA-OA pretreatment improves the digestibility of SB by sufficiently hydrolyzing hemicellulose into fermentable monosaccharides and oxidating lignin into soluble N-fertilizer with high nitrogen content (11.25%) and low C/N ratio (3.39). The enzymatic hydrolysates from DA-OA pretreated SB mainly composed of glucose was more suitable for the production of ABE solvents than the enzymatic hydrolysates from OA pretreated SB containing high ratio of xylose. The fermentation of enzymatic hydrolysates from DA-OA pretreated SB produced 12.12 g/L ABE in 120 h. These results suggested that SB could be utilized efficient, economic, and environmental by DA-OA pretreatment. [ABSTRACT FROM AUTHOR]

LaTiO2N photocatalysts were prepared by thermal ammonolysis of flux-synthesized La2Ti2O7 and La2TiO5, and were investigated for water oxidation. Though LaTiO2N derived from La2TiO5 appears defect-free by UV/Vis/near-IR and electron paramagnetic resonance (EPR) spectroscopy, its performance is much lower than that of conventional La2Ti2O7-derived LaTiO2N with defects. It is shown by Mott-Schottky analysis that La2TiO5-derived LaTiO2N has significantly lower donor density; this can result in insufficient built-in electric field for the separation of photogenerated electrons and holes. The lower donor density is also consistent with the smaller difference between the Fermi level and the valence-band maximum, which accounts for a lower oxidative power of the holes. In light of this discovery, the donor density was increased substantially by introducing anion vacancies through annealing in Ar. This resulted in improved performance. The CoO x-assisted La2TiO5-derived LaTiO2N annealed at 713 °C has a higher quantum efficiency (25 %) at 450 nm than high-performance conventional CoO x/LaTiO2N (21 %). [ABSTRACT FROM AUTHOR]

A series of promising cyan, green, and yellow emission (Ba, Sr)3(Si, Al)6(O, N)15:Eu2+ phosphors were synthesized by a Pechini-type sol-gel ammonolysis method. Variations in luminescence properties and crystal structure caused by the modification of phosphor composition were studied in detail. The prefired temperatures of the precursors play a key role in the process of forming the final products. Under UV light excitation, the as-prepared Ba3Si6O15:Eu2+ phosphor presents a strong cyan emission located at 498 nm. Moreover, the as-prepared oxynitride phosphors, Eu2+-activated (Ba1-ySry)3Si6-xAlxO15-μNδ (x = 0-1.2, y = 0-0.6), display a broader excitation band covering the entire visible region. Under blue light excitation, Ba3Si6-xAlxO15-μNδ:Eu2+ phosphors show a intense and narrow green emission at 520 nm, and the luminescent intensity can be enhanced by increasing Al content within a certain range. However, (Ba1-ySry)3Si6O15-μNδ:Eu2+phosphors exhibit green (520 nm) to yellow (554 nm) emission with increasing Sr content. Unexpectedly, Eu2+ doped Ba3Si6O9N4-type Ba3Si6O15-μNδ-1300 °C phosphor exhibits a bluish green emission and strong thermal quenching behavior. The (Ba1-ySry)3Si6-xAlxO15-μNδ:Eu2+ phosphors exhibit a small thermal quenching, and the quantum yields measured under 460 nm excitation could reach up to 89% for green Ba3Si6-xAlxO15-μNδ:Eu2+ phosphor and 71% for yellow (Ba1-ySry)3Si6xO15-μNδ:Eu2+ phosphor. White LEDs with tunable color temperature and higher color rendering index were fabricated by combining the prepared cyan Ba3Si6O15:Eu2+/green Ba2.91Eu0.09Si6-xAlxO15-μNδ (x = 0.06)/yellow (Ba0.97-ySry)3Eu0.09Si6O15-μNδ (y = 0.4) phosphor and a red phosphor with a UV or blue LED chip, indicating that they are promising phosphors for white LEDs. [ABSTRACT FROM AUTHOR]

The anion lattice of dielectric oxides A 5 Ta 4 O 15 (A=Sr, Ba) were modified using a mild ammonolysis treatment, which led to A 5 Ta 4 O 15–3 x N 2 x . N-doping was examined by varying the ammonolysis temperature and time in the ranges of 1023–1173 K and 2–20 h, respectively. Using sintered ceramics of A 5 Ta 4 O 15 , N-doping could be achieved up to 2 x ≈0.4 for both Sr 5 Ta 4 O 15–3 x N 2 x and Ba 5 Ta 4 O 15–3 x N 2 x . The nitridation of A 5 Ta 4 O 15 was not accompanied by a significant change in the crystal structure but a substantial evolution of the electronic structure was observed, as indicated by the marked shift in the band gap. Capacitance measurements revealed a ≈50% increase in the dielectric constants (κ) of A 5 Ta 4 O 15 upon N-doping. At 100 kHz and 295 K, κ was measured to be 37 for Sr 5 Ta 4 O 15 , 54 for Sr 5 Ta 4 O 14.4 N 0.4 , 26 for Ba 5 Ta 4 O 15 , and 43 for Ba 5 Ta 4 O 14.4 N 0.4 . All the Sr 5 Ta 4 O 15 , Ba 5 Ta 4 O 15 , and Ba 5 Ta 4 O 14.4 N 0.4 displayed temperature-stable dielectric behavior in the range, 30–450 K. On the other hand, Sr 5 Ta 4 O 14.4 N 0.4 exhibited a rapid increase in κ with increasing temperature, suggesting strong lattice anharmonicity. [ABSTRACT FROM AUTHOR]

Hydrogen is presumed to be the most promising energy carrier for sustainable energy. Herein, electrodes were made by thermal ammonolysis of CoMoO 4 ⋅nH 2 O microrods (MRs) supported on Ni foam (NF) at 300–700 ​°C, which is denoted as Co x MoN y O z H w MRs@NF-T (T ​= ​300–700). The HER performances of these electrodes were studied in 1.0 ​M KOH at room temperature. The best of these electrodes, the Co x MoN y O z H w MRs@NF-550, was fully characterized and investigated. It exhibits the lowest overpotential of 12 and 41 ​mV, respectively at the current density of 10 and 280 ​mA ​cm−2, which are much lower than those of the Pt/C@NF electrode (49 and 172 ​mV, respectively.). Such performance makes it one of the best HER electrodes. Remarkably, although its surface composition changed significantly after 50–130 ​h HER at 200 ​mA ​cm−2, the HER activity further improved in terms of overpotential. This work provided a method for the preparation of highly efficient NF-supported Co x MoN y O z H w electrodes. [Display omitted] • Co x MoN y O z H w MRs@NF-550 electrode was made using NH 3 under 550 ​°C. • It has an HER overpotential of 41 ​mV at 280 ​mA ​cm−2 in 1.0 ​M KOH aqueous solution. • It was found to be a heterostructure of Co(0), Co x MoN y O z H w , and CoMoN x O 4-x. • Its Tafel slope is only 15.7 ​mV dec−1, much smaller than that of Pt/C@NF. • Its activity increases despite of the surface-composition change after 130 ​h HER. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ammonolysis and hydration of glycolaldehyde is feasible only via catalysis of small molecules. • Ammonolysis of glycolaldehyde is favoured over hydration reaction. • Analysis of effective rate constants shows water as the predominant catalyst for the degradation of glycolaldehyde. • Degradation products of glycolaldehyde spontaneously participate in cluster formation. Catalytic routes for the hydration and ammonolysis reactions of glycolaldehyde (OHCH 2 CHO), a bifunctional carbonyl compound in the atmosphere, is investigated employing density functional methods. Energetics of reactions catalysed by water (monomer and dimer), ammonia, and ammonia-water complex have been explored. A substantial lowering of activation energies has been noticed in all these assisted pathways compared to the unassisted mechanism. Transition state theory estimates reveal larger effective rate constants for the water-assisted pathways (for both hydration and ammonolysis) than other catalytic agents.The structural and thermodynamic properties of the molecular clusters have been investigated in the gas phase. Thermodynamic data reveals the exothermic formation of clusters. Important role of hydrogen bonding network towards stabilising the molecular clusters was noticed. This study may shed light on the underlying molecular insights on new particle formation from degradation products of glycol aldehyde under atmospheric conditions. [ABSTRACT FROM AUTHOR]

The investigations carried out resulted in the improvement of technology of synthesis of the oligonucleotide primers, components of the PCR test systems produced in the RARI Microbe. The final product output was demonstrated to increase by 93 % when 25 % aquatic ammonium solution was used for ammonolysis, and by 16 % if solutions Cap A N1 and Cap B N 3 were used at the stage of capping. Application of the improved technology of oligonucleotide synthesis for gene diagnostic preparations production will permit to increase the amount of the output products and reduce expenses for high-priced reagents.

The thermochemical details of fabricating uranium nitride (UN) by ammonolysis of uranium tetraflouride (UF 4) were determined using density functional theory (DFT) and CALculation of PHAse Diagrams (CALPHAD) computational methods. The thermochemical data of all binary, ternary, and quaternary U–H–N–F phases were computed using DFT, and the data for the phases that have not been measured experimentally, including UN 2 and NH 4 F(g), were combined with existing experimentally-determined data for CALPHAD modeling. The DFT data were benchmarked using experimental Gibbs energy of reaction and experimental thermochemical data for individual species. Phase diagrams relevant to the ammonolysis reaction are depicted, showing regions of stability for solid U–N, U–F and U–N–F phases. An unidentified phase produced in a previous experiment was identified as UN 0.95 F 1.2 (UNF) by comparing its X-ray diffraction spectrum to the experimental spectrum, and its formation during the fabrication of UN from UF 4 is supported by the simulated phase diagram. It is calculated that UN 2 can be produced by the ammonolysis of UF 4 , but requires elevated temperatures, high NH 3 (g) partial pressure, and large amounts of flowing NH 3 (g) to avoid solid fluoride impurities in the uranium nitride. Likewise, U 2 N 3 can be produced instead at temperatures greater than 980 K. The use of silane (SiH 4) gas was investigated as a potential additive in the ammonolysis fabrication route to speed removal of fluorine. The addition of SiH 4 (g) offers little advantage to the removal of fluorine, and adds the complication of Si 3 N 4 formation. The use of DFT to fill in missing data to perform CALPHAD calculations demonstrated here allows for the determination of more comprehensive and trustworthy phase diagrams than the use of existing experimental data alone. [ABSTRACT FROM AUTHOR]

The sintering and thermal stability of BaTaO 2 N oxynitride perovskite were investigated as an alternative to SrTaO 2 N dielectric ceramics. The decomposition behaviors of the perovskites were similar, and the temperatures were slightly lower for BaTaO 2 N than for SrTaO 2 N. A BaTaO 2 N compact containing 2.5 wt% BaCO 3 sintering aid was sintered at 1400 °C in 0.2 MPa N 2 . Post-ammonolysis was necessary for the sintered black ceramics to recover the original red color. The insulating post-ammonolysis product with a relative density RD = 73.0% showed a real relative permittivity ε r = 620 and a tan δ = 0.4 at 10 2 Hz, which changed slightly to ε r = 320 with tan δ = 2.0 × 10 −2 at 10 8 Hz. The porosity was necessary to eliminate the electronic contribution affected on the extremely large values reported by Kim et al. in 2004 [1] . BaTaO 2 N ceramics showed better dielectric performance than SrTaO 2 N ceramics and it changed a little at temperatures up to 150 °C. [ABSTRACT FROM AUTHOR]

Metastable cobalt nitrides Co4N, Co3N, Co2N, and cobalt oxide nitride CoO0.74N0.24 were synthesized by ammonolysis of one single metastable azide precursor, [Co(NH3)5N3]Cl2, in high purity by controlled variation of the reaction conditions (temperature, duration, gas atmosphere, and flow rate). The alternative route towards cobalt nitrides by ammonolysis of CoBr2 proceeds via [Co(NH3)6]Br2 and Co(NH3)2Br2 to exclusively yield Co3N. For Co3N1.1 a complex magnetic behavior is observed: dominating ferromagnetic ordering at low temperatures and a small coercive field of 10 mT. Co2N orders antiferromagnetically below 10 K. Electronic structure calculations [DFT, generalized-gradient approximation (GGA)+ U] on CoO0.75N0.25 reveal that the experimentally observed rock-salt structure is less stable than the sphalerite-type polymorph by about 30 kJ mol-1 and possesses an antiferromagnetically ordered ground state. [ABSTRACT FROM AUTHOR]

Perovskite-type Nb-based oxynitrides (ANbO2N, A = Ba, Sr) exhibiting absorption of long light wavelengths up to (A = Sr) or even above 700 nm (A = Ba) were synthesized from stoichiometric perovskite-type oxides (ANbO3) by a typical thermal ammonolysis method. The preparation of BaNbO2N using BaNbO3 having an identical cubic-perovskite-type structure was demonstrated to effectively improve the surface and bulk crystallinity of the oxynitride because of the absence of a structural transition during nitridation and the stoichiometric 1:1 Ba/Nb ratio between the oxides and oxynitrides. The resulting BaNbO2N photoanode exhibited photoelectrochemical water oxidation activity with a current density of 0.85 mA cm-2 at 1.23 VRHE and a faradaic efficiency close to unity under simulated solar illumination (AM 1.5G). The associated incident photon-to-current efficiency in the range of 740-480 nm showed that BaNbO2N produces a photoanodic current at 740 nm, the longest response wavelength ever reported for a photoanode based on an (oxy)nitride. [ABSTRACT FROM AUTHOR]

Four 6-substituted 4-amino-pyrimido[4,5- b ]indole 2′-deoxyribonucleoside triphosphates ( dA BX TP s) were prepared by glycosylation of 4,6-dichloropyrimidoindole followed by ammonolysis, cross-coupling and triphosphorylation. They were found to be moderate to good substrates for DNA polymerases in primer extension. They also exerted fluorescence with emission maxima 335–378 nm. When incorporated to oligonucleotide probes, they did not show significant mismatch discrimination but the 6-benzofuryl 4-amino-pyrimido[4,5- b ]indole nucleotide displayed a useful sensitivity to protein binding in experiment with SSB protein. [ABSTRACT FROM AUTHOR]

A bimetallic molecular system made of gallium (III) tris(dimethyl)amide Ga(NMe 2 ) 3 and manganese (II) bis(trimethylsilyl)amide Mn[N(SiMe 3 ) 2 ] 2 (Me = CH 3 , fixed initial Mn-content 10 at.%) was subjected to ammonolysis in refluxing/liquid ammonia. Upon isolation at room temperature, the amide-imide mixed metal precursor was pyrolyzed at elevated temperatures under an ammonia flow by two different routes. Route 1 consisted of a direct nitridation at high temperatures of 500, 700 or 900 °C. In route 2, a low temperature pyrolysis at 150 °C was applied prior to nitridation at the same final temperatures as in route 1. All nanopowders were characterized by XRD diffraction, FT-IR spectroscopy, and SEM/EDX microscopy and analysis. Thorough magnetization measurements in function of magnetic field and temperature were carried out with a SQUID magnetometer. In all samples, the paramagnetic phase of GaMnN was accompanied by an antiferromagnetic by-product linked to a Mn-containing species from decomposition and oxidation of Mn-precursor excess. The Mn-contents in the crystalline GaMnN, i.e. , Mn-incorporated in GaN crystal lattice, were of the order of 2–3 at.% mostly independent on the nitridation route whereas the latter had a pronounced effect on amounts of the antiferromagnetic by-product. [ABSTRACT FROM AUTHOR]

Lanthanum doped barium titanate was nitridated by thermal ammonolysis with a newly designed reactor, which performs extended efficiency to supply ammonia with less decomposition at elevated temperatures above 600 °C. The kinetics of nitrogen-uptake was studied systematically at elevated temperatures. Nitrogen-content, thermal stability and crystallographic phase of nitridated lanthanum doped barium titanate were characterized by several techniques. The final nitrogen-content of nitridated lanthanum doped barium titanate was much higher than the content of lanthanum, resulting in the formation of oxygen vacancies compensating the additional negative electrical charge of nitrogen anions occupying regular oxygen sites in the lattice. Through thermal ammonolysis, strongly reducing conditions because of the decomposition of ammonia generating hydrogen gas causes the formation of barium orthotitanate as a secondary phase. Ammonolysis temperature below 800 °C and suppression of thermal decomposition of ammonia gas are essential to realize a nitridated lanthanum doped barium titanate as a single phase. [ABSTRACT FROM AUTHOR]

Amides of 4-aryl(hetaryl)-2-pyrrolidone-3-carboxylic acids have been prepared via ammonolysis of the corresponding esters of pyrrolidone carboxylic acids. The products structure has been characterized by means of IR, H NMR, H-C HMQC, and HMBC spectroscopy. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop a new oil-in-water emulsion template for the preparation of highly porous poly(lactide- co-glycolide) (PLGA) microspheres having a spongelike skeleton and a pore-closing functionality. A dispersed phase consisting of isopropyl formate and PLGA was emulsified in an aqueous phase. Ammonia was added toward this emulsion, in order to induce ammonolysis in the dispersed phase. Subsequently, isopropyl formate was broken into water-soluble isopropanol and formamide. As they functioned as anti-solvents against PLGA, microsphere hardening occurred. Also, their leaching into the aqueous phase led to the formation of highly porous, spongelike microspheres. The microsphere porosity was found to be controlled by adjusting isopropyl formate volume, PLGA type and concentration, ammonia volume, and ammonia-isopropyl formate molar ratio. When these dried microspheres were dispersed into an aqueous phase, the pores closed themselves autonomously. Herein, the self-closing capability of the microspheres was greatly influenced by microsphere Tg and the aqueous phase temperature. FITC-dextran and lysozyme were successfully encapsulated into the microspheres by simply equilibrating their aqueous solutions with the self-closing microspheres. In conclusion, the new emulsion template did not use either a halogenated organic solvent or conventional porogens. It did not require high-shear or high-energy mixing devices that must be used in the practice of most contemporary microencapsulation techniques. Despite these facts, this new technique was able to fabricate spongelike microspheres with an extremely high porosity and an outstanding pore-closing functionality. [ABSTRACT FROM AUTHOR]

Porous materials based on a framework containing T-N linkages, where T represents silicon or silicon and aluminium atoms, have been prepared by the ammonolysis at low temperature of the corresponding silicon and aluminium chlorides in an ionic liquid, both in the presence and in the absence of mineralizing agents such as pyrrolidine, ammonia and sodium amide. IR spectroscopy and XPS data are consistent with these materials having a framework based on T-NH-T groups (T = Si or Al), that contain also a large fraction of T-NH 2 terminal groups. Moreover, XPS evidences the presence of Si-NH-Al groups whenever aluminium is present in the solid. The basic strength of the materials has been determined by pyrrole adsorption, and it has been found that the average basic strength increases with the population of T-NH-T groups and with the aluminium content of the framework. However, this strength is lower than that of a calcined hydrotalcite (Al/(Al + Mg) = 0.33) taken as a reference. These materials are active and very selective catalysts in the Michael addition reaction between chalcone [and malononitrile (pK a 11), but turned to be inactive when diethylmalonate having a weaker acidity (pK a 13.3) is used as donor. [ABSTRACT FROM AUTHOR]

Oxynitride glasses are mixed-anion glasses, in which the oxygen atoms have been partially substituted by either two-fold (N d ) or three-fold (N t ) coordinated nitrogen atoms, introducing additional bonds and thereby constraining the glass network and enhancing the atomic packing density. Phosphate glasses are more prone to undergo nitridation via ammonolysis at relatively low temperature compared to other types of oxide glasses, but here the question is how the nitridation influences the glass transition, structure, and dynamics in phosphate glasses. Here, we answer this question by taking sodium and lithium metaphosphate oxynitride glasses as model systems. Using differential scanning calorimetry (DSC), we measure the effect of the atomic nitrogen/phosphorus (N/P) ratio on the glass transition temperature ( T g ), jump in isobaric heat capacity at the glass transition (Δ C p ), glass transition width (Δ T g ), and liquid fragility index ( m ) of these model glasses. The results show that the nitridation causes an increase in the atomic packing density and T g . In addition, Δ T g increases and m decreases with increasing N/P, both implying that the liquids become stronger upon nitridation, whereas Δ C p does not vary systematically with N/P within the error range. We discuss the origin of these changes in terms of the underlying changes in the short- and intermediate-range order structures, as detected by Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Ni3FeN nanoparticles with a particle size of ≈100 nm and a thickness of ≈9 nm are successfully synthesized by thermal ammonolysis of ultrathin NiFe‐layered double hydroxide ultrathin nanosheets. The Ni3FeN nanoparticles exhibit excellent catalytic performance and high stability in electrochemical overall water splitting. [ABSTRACT FROM AUTHOR]

A novel ethynylaniline-terminated polysilazane (PCSN) was synthesized from the ammonolysis reaction of dichloromethylsilane (MeSiHCl2) and p-phenylenediamine, by which terminal ethynyl groups were introduced into the resultant PCSN. Different average molecular weight PCSNs obtained with adjusting the molar ratios between p-phenylenediamine and MeSiHCl2 were used to investigate the influence of average molecular weights and contents of terminal ethynyl groups on thermal properties and ceramic conversions of PCSNs. The structure of PCSN was characterized using Fourier transform infrared, proton, carbon-13, and silicon-29 nuclear magnetic resonance spectroscopies. Among all the PCSN precursors, PCSN-4 has the lowest curing temperature (237.1°C) and the highest enthalpy (863.0 J g−1) because of its highest content of terminal ethynyl groups, improving its cross-linking. The thermal properties of cured PCSN were studied by means of thermogravimetric analysis under nitrogen atmosphere. The collaborative effect from both the average molecular weight and the contents of terminal ethynyl groups gave PCSN-3 the best thermal stability. The temperature of 5% mass loss was 564°C and the residual mass at 900°C was 84.4%. After sintering at 1450°C in argon atmosphere, PCSN-3 thermoset turned into black solids composited of β-silicon carbide (β-SiC), α-silicon nitride, α-SiC, and free carbon with a yield of 78.4%, indicating PCSN had the potential to be used as ceramic precursors. [ABSTRACT FROM AUTHOR]

Highly crystalline niobium- and tantalum-based oxynitride perovskite nanoparticles were obtained from hydrothermally synthesized oxide precursors by thermal ammonolysis at different temperatures. The samples were studied with respect to their morphological, optical and thermal properties as well as their photocatalytic activity in the decomposition of methyl orange. Phase pure oxynitrides were obtained at rather low ammonolysis temperatures between 740 °C (CaNbO 2 N) and 1000 °C (BaTaO 2 N). Particle sizes were found to be in the range 27 nm–146 nm and large specific surface areas up to 37 m 2 g −1 were observed. High photocatalytic activities were found for CaNbO 2 N and SrNbO 2 N prepared at low ammonolysis temperatures. CoO x as co-catalyst was loaded on the oxynitride particles resulting in a strong increase of the photocatalytic activities up to 30% methyl orange degradation within 3 h for SrNbO 2 N:CoO x . [ABSTRACT FROM AUTHOR]

Partial substitution of cations and anions in perovskite-type materials is a powerful way to tune the desired properties. The systematic variation of the cations size, the partial exchange of O 2− for N 3− and their effect on the size of the optical band gap and the thermal stability was investigated here. The anionic substitution resulted in the formation of the orthorhombic perovskite-type oxynitrides Mg 0.25 Ca 0.65 Y 0.1 Ti(O,N) 3 , Ca 1- x Y x Zr(O,N) 3 , and Sr 1– x La x Zr(O,N) 3 . A two-step synthesis protocol was applied: i) (nano-crystalline) oxide precursors were synthesized by a Pechini method followed by ii) ammonolysis in flowing NH 3 at T = 773 K (Ti) and T = 1273 K (Zr), respectively. High-temperature synthesis of such oxide precursors by solid–state reaction generally resulted in phase separation of the different A -site cations. Changes of the crystal structures were investigated by Rietveld refinements of the powder XRD data, thermal stability by DSC/TG measurements in oxygen atmosphere, oxygen and nitrogen contents by O/N analysis using hot gas extraction technique, and optical band gaps by photoluminescence spectroscopy. By moving from Mg 0.25 Ca 0.65 Y 0.1 Ti(O,N) 3 via Ca 1– x Y x Zr(O,N) 3 to Sr 1– x La x Zr(O,N) 3 , the degree of tilting of the octahedral network is reduced, as observed by an increase in the B – X – B angles caused by the simultaneously increasing effective ionic radius of the A -site cation(s). In general, increasing substitution levels on the A -site (Y 3+ and La 3+ ) are accompanied by an enhanced replacement of O 2− by N 3− . In all three systems, this anionic substitution resulted in a reduction of the optical band gap by approximately 1 eV (Ti) and up to 2.1 eV (Zr) compared to the respective oxides. For Mg 0.25 Ca 0.65 Y 0.1 Ti(O,N) 3 an optical band gap of 2.2 eV was observed, appropriate for a solar water splitting photocatalyst. The Zr-based oxynitrides required a by a factor of 2 higher nitrogen contents to significantly reduce the optical band gap and the measured values of 2.9 eV–3.2 eV are larger compared to the Ti-based oxynitride. Bulk thermal stability was revealed up to T = 881 K. In general, the thermal stability decreased with increasing substitution levels due to an increasing deviation from the ideal anionic composition as demonstrated by O/N analysis. [ABSTRACT FROM AUTHOR]

Nitrogen doped zinc oxide (ZnO) nanoparticles have been synthesized using a colloidal route and low temperature nitridation process. Based on these results, 200 nm thick transparent ZnO thin films have been prepared by dip-coating on SiO 2 substrate from a ZnO colloidal solution. Zinc peroxide (ZnO 2 ) thin film was then obtained after the chemical conversion of a ZnO colloidal thin film by H 2 O 2 solution. Finally, a nitrogen doped ZnO nanocrystalline thin film (ZnO:N) was obtained by ammonolysis at 250 °C. All the films have been characterized by scanning electron microscopy, X-ray diffraction, X-Ray photoelectron spectroscopy and UV–Visible transmittance spectroscopy. [ABSTRACT FROM AUTHOR]

A new oxynitride Ruddlesden-Popper phase K 1.6 Ca 2 Nb 3 O 9.4 N 0.6 .1.1H 2 O was synthesized by the topochemical ammonolysis reaction at 700 °C from the oxide Dion-Jacobson phase KCa 2 Nb 3 O 10 in the presence of K 2 CO 3 . The oxynitride showed good stability with a little loss of nitrogen, even after a few months of exposure to air. Its crystal structure was solved by Rietveld refinement of X-ray powder diffraction data in space group P4/mmm and considering a two-phase mixture, due to the difference in the degree of hydration, with a = 3.894(2) Å and c = 17.90(8) Å for the most hydrated phase and a = 3.927(6) Å and c = 17.09(2) Å for the less one. Optical band gaps were measured by diffuse reflectance in the UV-Visible range indicating a red shift of Eg to the visible region. The oxynitride layered perovskite was then protonated and exfoliated into nanosheets. TEM images and SAED patterns of the nanosheets proved that exfoliation was successful, showing lattice parameters quite compatible with the Rietveld refinement. [ABSTRACT FROM AUTHOR]

LnCrO3−xNx perovskites with Ln = La, Pr and Nd and nitrogen contents up to x = 0.59 have been synthesised through ammonolysis of LnCrO4 precursors. These new materials represent one of the few examples of chromium oxynitrides. Hole-doping through O2−/N3− anion substitution suppresses the magnetic transition far less drastically than Ln3+/M2+ (M = Ca, Sr) cation substitutions because of the greater covalency of metal–nitride bonds. Hence, nitride-doping is a more benign method for doping metal oxides without suppressing electronic transitions. [ABSTRACT FROM AUTHOR]

We present how the introduction of anion vacancies in oxyhydrides enables a route to access new oxynitrides, by conducting ammonolysis of perovskite oxyhydride EuTiO3-xHx (x ~ 0.18). At 400 °C, similar to our studies on BaTiO3-xHx, hydride lability enables a low temperature direct ammonolysis of EuTi3.82+O2.82H0.18, leading to the N3-/H--exchanged product EuTi4+O2.82N0.12?0.06. When the ammonolysis temperature was increased up to 800 °C, we observed a further nitridation involving N3-/O2- exchange, yielding a fully oxidized Eu3+Ti4+O2N with the GdFeO3-type distortion (Pnma) as a metastable phase, instead of pyrochlore structure. Interestingly, the same reactions using the oxide EuTiO3 proceeded through a 1:1 exchange of N3- with O2- only above 600 °C and resulted in incomplete nitridation to EuTiO2.25N0.75, indicating that anion vacancies created during the initial nitridation process of EuTiO2.82H0.18 play a crucial role in promoting anion (N3-/O2-) exchange at high temperatures. Hence, by using (hydride-induced) anion-deficient precursors, we should be able to expand the accessible anion composition of perovskite oxynitrides. [ABSTRACT FROM AUTHOR]

The article reviews the different routes for recycling of polyethylene terephthalate. Chemical recycling processes are divided into six groups: methanolysis, glycolysis, hydrolysis, ammonolysis, aminolysis, and other methods. In a large collection of researches for the chemical recycling of PET, the primary objective is to increase the monomer yield while reducing the reaction time and/or carrying out the reaction under mild conditions. This article also presents the impact of the new recyclable catalysts such as ionic liquids on the future developments in the chemical recycling of PET. [ABSTRACT FROM AUTHOR]

In this study, an enzyme catalyzed in situ forming hydrogel based on tyramine conjugated high methoxyl content gum tragacanth (TA-HMGT) was prepared and characterized. TA-HMGT was synthesized via heterogeneous ammonolysis of methyl ester groups of HMGT. Then, the hydrogel was prepared via horseradish peroxidase catalyzed coupling reaction in the presence of hydrogen peroxide. Hydrogel properties, such as gelation time, swelling/degradation behavior and rheological properties could be adjusted by tuning the gelation parameters and extent of tyramine conjugation. This system was a soft elastic hydrogel with appropriate biocompatibility. The fast gelation of the hydrogel is desirable for clinical applications. Also, in vitro bovine serum albumin release from the synthesized hydrogel showed good release profile with limited burst release. [ABSTRACT FROM AUTHOR]

Novel 2′-deoxy-2′-β-fluoro-threose purine phosphonic acid analogues were designed and racemically synthesized from 2-propanone-1,3-diacetate. Condensation successfully proceeded from a glycosyl donor9under Vorbrüggen conditions. Cross-metathesis of vinyl analogues13and23with diethyl vinylphosphonate yielded the desired nucleoside phosphonate analogues14and24, respectively. Ammonolysis and hydrolysis of phosphonates yielded the nucleoside phosphonic acid analogues16,19,26,and29. The synthesized nucleoside analogues were subjected to antiviral screening against human immunodeficiency virus (HIV)-1. Adenine analogue18exhibited weak in vitro activities against human immunodeficiency virus (HIV)-1. [ABSTRACT FROM PUBLISHER]

[Display omitted] • PLA can be burned as a fuel because the incineration is regard as carbon neutral. • Pyrolysis of PLA with MgO and its co-pyrolysis with biomass is very promising. • Alcoholysis of PLA is considered to be the most suitable method for chemical recovery of PLA. • The hydrolysis of PLA can upcycle lactic acid with low energy consumption compared to that from starch fermentation. • The products have higher added value and wider usages during ammonolysis of PLA. Polylactic acid (PLA) is currently the highest production of all bio-based plastics globally. Its production will increase year by year to replace part of petroleum-based plastics to reduce environmental pollution and curb carbon emissions. However, the raw materials for synthesizing PLA mainly come from sugary foods, and mass production will pose a threat to food security. In addition, the degradation rate of PLA is slow, and a large amount of waste PLA accumulation still causes pollution. As a high-quality carbon source, compared with direct degradation, recycling PLA is a more green and environmentally friendly method. Because PLA can not only be depolymerized into raw materials for synthesizing PLA but also can be upcycled to chemicals required by various industries, which helps to reduce the use of petroleum resources. In addition, the recycling of PLA helps to reduce CO 2 emissions, because the source of PLA does not consume petroleum resources, but rather fixes CO 2 in the air. This review summarizes the works of upcycling waste PLA as an alternative carbon source for energy and other chemicals from the perspectives of tertiary and quaternary recycling, which provides a reference for the proper treatment of a large amount of waste PLA. [ABSTRACT FROM AUTHOR]

[Display omitted] • Low temperature synthesis of CeO 2-x N x phases by ammonolysis of cerium nitrate. • Method of synthesis and photoelectrochemical HER efficiency correlated. • Tuning redox properties by substituting N and creating anionic vacancies. • Carbon-free oxynitride materials for overall water splitting. A facile solid–gas interface method for anionic substitution of nitrogen in CeO 2 lattice is reported. In this study, a low temperature ammonolysis method is developed as an alternate to high temperature ammonolysis of CeO 2. Cerium nitrate precursor is thermally treated directly by ammonia gas at 550 °C to prepare cerium-oxy-nitride samples which are tested for photoelectrochemical hydrogen evolution activity (HER). The CeO 2-x N x material synthesized by low temperature ammonolysis of cerium nitrate shows lower onset potential η light = -1.04 V vs Ag/AgCl under light, large photocurrent density of 0.2 µA/cm2 at −0.4 V applied potential. The proposed method of ammonolysis of salt precursors is an excellent method for the synthesis of oxy-nitrides at low temperatures without residual carbon impurities for higher photocatalytic efficiencies. [ABSTRACT FROM AUTHOR]

This paper describes a safer, scalable and continuous process for synthesis of picramide. The process consists of two steps: step-1. nitration of p-nitroanisole (PNAN) to 2,4,6-trinitrianisole (TNAN); step-2. ammonolysis of TNAN to picramide. Both the steps were optimized in flow, with yield of 90% and 98% in step-1 and step-2 respectively. Picramide with HPLC purity greater than 99% was obtained. When compared with batch, in step-1, flow process provided significant advantage in selectivity and yield. The optimized flow process was scaled to 25 g/hr production rate in a laboratory flow reactor. The method can be considered fit for the safe production of picramide at commercial scale., (© 2022 Wiley-VCH GmbH.)

Treatment of [{Ti(η5-C5Me5)(μ-NH)}3(μ3-N)] (1) with zirconium or hafnium tetrachloride adducts [MCl4(thf)2] affords complexes [Cl3M{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] (M = Zr (2), Hf (3)). Titanium chloride complexes [Cl2Ti{(μ3-N)2(μ3-NH)Ti3(η5-C5Me5)3(μ3-N)}] (4) and [(Me2NH)ClTi{(μ3-N)3Ti3(η5-C5Me5)3(μ3-N)}] (5) are obtained by reaction of 1 with [TiCl4−x(NMe2)x] (x = 2, 3). The dimethylamine ligand in 5 is displaced by pyridine to give the analogue complex [(py)2ClTi{(μ3-N)3Ti3(η5-C5Me5)3(μ3-N)}] (6). Treatment of the titanium chloride complexes 4 and 5 with sodium cyclopentadienide or lithium bis(trimethylsilyl)amide reagents leads to the cube-type nitrido derivatives [RTi{(μ3-N)3Ti3(η5-C5Me5)3(μ3-N)}] (R = η5-C5H5 (7), N(SiMe3)2 (8)). The reaction of the zirconium trichloride complex 2 with [Tl(C5H5)] yields exclusively the dichloride-monocyclopentadienyl derivative [(η5-C5H5)Cl2Zr{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] (9). However, the treatment of 2 with excess [Na(C5H5)] causes further chloride replacement in 9 and subsequent cyclopentadiene elimination to give [(η5-C5H5)Zr{(μ3-N)3Ti3(η5-C5Me5)3(μ3-N)}] (10) via intermediates [(η5-C5H5)2ClZr{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}] (11) and [(η5-C5H5)ClZr{(μ3-N)2(μ3-NH)Ti3(η5-C5Me5)3(μ3-N)}] (12). Treatment of 2 or 9 with [Mg(C5H5)2] leads to the magnesium derivative [(η5-C5H5)Mg(μ-Cl)2(η5-C5H5)Zr{(μ4-N)(μ3-N)(μ3-NH)Ti3(η5-C5Me5)3(μ3-N)}] (13), which can be visualized as a result of the incorporation of one [Mg(η5-C5H5)Cl] moiety to complex 12. In contrast to the metathesis process with [M(C5H5)x] derivatives and subsequent C5H6 eliminations, the reaction of 2 with potassium pentamethylcyclopentadienide in toluene produces the paramagnetic derivative [K(μ-Cl)3Zr{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] (14) and C10Me10. Complex 14 reacts with one equivalent of 18-crown-6 or cryptand-222 to give the molecular complex [(18-crown-6)K(μ-Cl)3Zr{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] (15) or the ion pair [K(crypt-222)][Cl3Zr{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] (16). The X-ray crystal structures of 2, 8, 13 and 15 have been determined. [ABSTRACT FROM AUTHOR]

SrMo(O,N) 3 and SrW(O,N) 3 oxynitride powders were synthesized via a solvothermal route followed by ammonolysis. Their rapid densification by spark plasma sintering with a heating rate of 300–400 °C/min under a uniaxial pressure of 100 MPa yielded dense monoliths. The lowest open porosity achieved was 0 vol% for SrMo(O,N) 3 and 7.6 vol% for SrW(O,N) 3 . The compacted monoliths were characterized by elemental analysis, electron microscopy (SEM, TEM) coupled with energy dispersive X-ray spectroscopy (EDX), as well as X-ray diffraction (XRD). Rietveld refinement of the XRD patterns revealed in the case of the compacted SrMo(O,N) 3 the formation of small amount of ternary oxides (Sr 3 Mo 2 O 7 /SrMoO 4 /Sr 3 MoO 6 ), molybdenum nitride (Mo 2 N), as well as metallic Mo. On the contrary, SrW(O,N) 3 exhibited significant decomposition after consolidation, with SrWO 4 /Sr 3 WO 6 being main components beside SrMo(O,N) 3 , accompanied by tungsten nitride (WN) and metallic W. Thus, rapid SPS enables the densification of oxynitrides with high density and acceptable purity that were hardly achieved earlier. [ABSTRACT FROM AUTHOR]