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Phenol, acetic acid, and naphthalene, as the most common and refractory intermediates during the supercritical water gasification (SCWG) of biomass were selected as the model compounds, and the their mutual interactive effects during the SCWG process were investigated. The gasification performances of one-component solutions and their two- and three-components mixtures were thoroughly studied in a tubular reactor at 550°C, 25 MPa, reaction time of 20 s. Results showed that for the one-component solutions, the difficulty degree of degradation order of the three compounds was naphthalene > phenol > acetic acid, and concentration of the reactants showed little influence on the gasification efficiencies. For the two-components solutions, acetic acid promoted the degradation of phenol and naphthalene, and the gasification of phenol and naphthalene inhibited each other. The 3D curved surface for gas yields and total organic concentration (TOC) removal efficiencies of three-components mixture clearly showed that the increasing concentration of acetic acid increased the H2 and CO2 yields. While the interactive effects of the three compounds were favorable for CH4 yield. Acetic acid played a positive effect on TOC removal, while the increasing concentration of naphthalene was unfavorable for the degradation of TOC, and the inhibition effect was higher when phenol existed. © 2017 American Institute of Chemical Engineers Environ Prog, 2017

Materials with giant spin splitting are desired for spintronic applications. The fabrications of spintronic devices from half metals with one spin direction are often hampered, however, by stray magnetic fields, domain walls, short spin coherence times, scattering on magnetic atoms or magnetically active interfaces, and other characteristics that come along with the magnetism. The surfaces of topological insulators, or Dirac/Weyl semimetals, could be an alternative, but production of high-quality thin films without the presence of the bulk states at the Fermi energy remains very challenging. Here, by utilizing angle-resolved photoemission spectroscopy, a record-high Dresselhaus spin-orbit splitting of the bulk state in the nonmagnetic IrBiSe is found. The band structure calculations indicate that the splitting band is fully spin-polarized with 3D chiral spin texture. As a source of spin-polarized electrons, lightly doped IrBiSe is expected to generate electric-field-controlled spin-polarized currents, free from back scattering, and could host triplet and Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) superconductivity.

Half-metals are a class of materials that are metallic only for one spin direction, and are essential for spintronics applications where one needs to read, write, store and transfer spin-data. This spin sensitivity appears to restrict them to be magnetic, and the known examples indeed are. The fabrication of real spintronic devices from such materials is often hampered, however, by stray magnetic fields, domain walls, short spin coherence times, scattering on magnetic atoms or magnetically active interfaces, and other characteristics that come along with the magnetism. The surfaces of topological insulators, or Dirac or Weyl semimetals, could be an alternative, but production of high-quality thin films without the presence of the bulk states at the Fermi level remains very challenging. Here we introduce non-magnetic half-metals and demonstrate that this state is realized in IrBiSe. Using angle-resolved photoemission spectroscopy and band structure calculations we find a record-high Dresselhaus spin-orbit splitting, fully spin-polarized remnant Fermi surfaces and a chiral 3D spin-texture, all with no magnetism present. Promising applications include using IrBiSe as a source of spin-polarized electrons, and lightly doped IrBiSe is expected to generate electric-field-controlled spin-polarized currents, free from back scattering, and could host triplet superconductivity.

BACKGROUND Corynebacterium glutamicum was engineered for improvement of L-lysine production and minimization of by-products synthesis by genetically engineering. RESULTS The most promising recombinant strain C. glutamicum Lys9 produced 62.1 mmol L-1 L-lysine with substrate-specific yield (YP/S) of 0.28 mol per mol of glucose in shake flasks fermentation, whereas parental strain showed more than four times lower L-lysine production and more than 10 times lower biomass-specific yield (YP/X) than that of C. glutamicum Lys9. L-lysine production and cell growth were drastically decreased by isocitrate dehydrogenase (ICD) attenuation in aceE deletion strains, indicating that down-regulation of ICD activity in aceE deletion strains adversely affects L-lysine production. In fed-batch fermentation, C. glutamicum Lys9 produced 526 mmol L-1 L-lysine, i.e. 96.8 g L-1 L-lysine-HCl with high yield of 0.422 mol per mol of glucose and productivity of 2.69 g L-1 h-1. Corynebacterium glutamicum Lys9 was devoid of any detectable L-alanine and L-lactate synthesis. CONCLUSION Superior to classical producers to some degree, C. glutamicum Lys9 is more adaptable for industrial L-lysine production. In addition to L-lysine, pyruvate, oxaloacetate (OAA) and L-valine were produced by C. glutamicum Lys9, suggesting further optimization to improve L-lysine production by engineering the L-lysine and/or NADPH biosynthetic pathway. © 2013 Society of Chemical Industry

Morphology-dependent properties of nano-/microspheres with hollow interiors have attracted immense attention because of the unique properties and potential technological applications in various fields, such as electronics, optoelectronics, selective catalysis, controlled release, and delivery, etc. [1] Inspired by the excellent properties, the study on the fabrication of transition-metal dichalcogenides with desired morphologies is continually being intensified. [2] In particular, nickel dichalcogenides (such as NiS2, NiSe2 and NiTe2) have become the focus in recent years due to their novel electric and magnetic properties and important technological applications in various fields. It is well known that NiS2 is of particular interest as a Mott–Hubbard insulator with anomalous antiferromagnetic long-range order and a metal-insulator transitional body in NiS2xSex, whereas NiSe2 is a typical Pauli paramagnet with metallic conductivity and, therefore, is suitable as a storage energy material for rechargeable lithium batteries. [3] More importantly, NiSe2 can also be applied as the prominent Pt-free electrocatalyst for dye-sensitized solar cells (DSSCs), which shows better catalytic activity in the reduction of triiodide than Pt electrode. [4] Furthermore, NiTe2 is a promising back contact to CdTe/CdS solar cells with exceeding 10 % conversion efficiencies. [5] A variety of chemical and physicochemical methods, such as solid-state synthesis, elemental direct reaction, and mechanical alloying have been used to fabricate nickel dichalcogenides; nevertheless, there is barely a report about the synthesis of NiS2, NiSe2, and NiTe2 hollow spheres up to now, partly due to the difficulties in fabricating transition-metal dichalcogenides with regular morphologies. [6] Herein, we have successfully devised a simple and general hydrothermal synthetic route to prepare the uniform NiS2 hollow spheres in the presence of l-cysteine and urea. Especially, NiSe2 and NiTe2 hollow spheres could be obtained through a chemical conversion method under hydrothermal conditions by using NiS2 hollow spheres as the precursor, respectively. Meanwhile, NiS and NiO hollow spheres could also be successfully synthesized by the calcinations of NiS2 hollow spheres at different temperatures. A probable formation mechanism of the resulting products has been proposed, which offers a designable route to prepare transition-metal dichalcogenides as well as transformations between sulfides and oxides. The magnetic properties of as-prepared nickel dichalcogenides have been investigated in detail and indicate an antiferromagnetic behavior for NiS2 and NiTe2 hollow spheres and a paramagnetic behavior for NiSe2 hollow spheres. Scheme 1 illustrates the design process and possible scenario for the formation of nickel dichalcogenide hollow spheres. Firstly, l-cysteine is dispersed in deionized water and simultaneously capped by Ni ions due to the coordination of functional groups in the l-cysteine molecules, such as NH2, COOH, and SH, which has a strong tendency to coordinate with inorganic cations. [7] Urea can be used to

The new title compound is prepared by solid state reaction of a stoichiometric mixture of CaO2, Os, Fe2O3, and KClO4 (Pt capsule, 6 GPa, 1500 °C, 1 h) and characterized by synchrotron powder XRD, magnetic and electrical resistivity measurements, and DFT calculations.

CaOsO3 and SrOsO3 are synthesized by high-pressure solid state reactions of CaO or SrO and OsO2 (Pt capsule, 6 GPa, 1500—1700 °C, 1 h).

NiS2 hollow spheres are hydrothermally synthesized from a mixture of Ni(NO3)2, L-cysteine, urea, and H2O (autoclave, 140 °C, 24 h).

Oxygen-deficient title compounds with 0 ≤ δ ≤ 0.35 are synthesized from stoichiometric amounts of LaAs, ZnO, and Zn (belt-type high-pressure apparatus, Au capsule, Ar, 6 GPa, 1300 °C, 2 h).

Polycrystalline samples of Sr3Co2-xZnxO6 (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) are synthesized from mixtures of Co, SrO2, and ZnO (6 GPa, 1400 °C, 1 h) and characterized by XRD, electrical resistivity, and magnetic measurements.

The title compound is characterized by neutron diffraction at temperatures between 50 and 295 K.

A postspinel phase of CdRh2O4 is prepared by solid state reaction of a stoichiometric mixture of CdO and Rh2O3 (Au capsule, 6 GPa, 1400 °C, 1 h).

The crystal structure of the title compound is determined by neutron and synchrotron powder diffraction measurements in the temperature range 3—320 K.

Single crystals of the new title compound are prepared by a flux method from mixtures of Ca3OsO6 (obtained from stoichiometric amounts of CaO2 and Os, Pt capsule, 6 GPa, 1500 °C, 1 h), LiCl, and KCl in a mass ratio of 1:5:2 (Pt crucible, 750 °C, 12 h).

Na2OsO4 crystals were grown by a NaCl flux method under high pressure. It crystallizes in the Ca2IrO4-type structure without having additional elements or metal vacancies, which are usually accommodated. It appears that Na2OsO4 is a metal-stoichiometric Ca2IrO4-type compound never been synthesized to date. Na2OsO4 has the octahedral environment of Os6+O6 so that the electronic configuration is 5d2, suggesting the magnetic S=1 ground state. However, magnetization, electrical resistivity, and specific heat measurements indicated that the non-magnetic S=0 state is much likely for Na2OsO4 than the S=1 state. Band structure calculations and the structure analysis found that the disagreement is probably due to the statically uniaxial compression of the OsO6 octahedra, resulting in splitting of the t 2 g band.

While there already exit some routes to prepare carbides, highly efficient and facile routes are still desired to meet the increasing demand on carbides. By a facile solid-state reaction process using graphite-like phase of C3N4 (g-C3N4) as the carbonizing reagent, we synthesized three technologically important carbides including cubic NbC and TaC, and hexagonal WC nanoparticles at relatively low temperature (1150 degrees C). The products were characterized by power X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM). The results show that g-C3N4 is a highly efficient carbonizing reagent and the oxides Nb2O5, Ta2O5 and WO3 are completely converted into the corresponding carbides at 1150 degrees C, which is significantly lower than that reported for the commercial preparation of the carbides, typically > 1600 degrees C. The NbC, TaC and WC nanoparticles are found to have an average particle size of 4, 35 and 60 nm, respectively. An important feature of this solid-state reaction process is that g-C3N4 plays double roles as both efficiently reducing and carbonizing reagent. (c) 2006 Elsevier B.V. All rights reserved.