共查询到20条相似文献,搜索用时 31 毫秒
1.
Olaf Baake Peter S. Hoffmann Andreas Klein Beatrix Pollakowski Burkhard Beckhoff Marina L. Kosinova Nadeshda I. Fainer Veronica S. Sulyaeva Valentina A. Trunova Wolfgang Ensinger 《Analytical and bioanalytical chemistry》2009,395(6):1901-1909
Films of BC
x
N
y
were produced in a plasma-enhanced chemical vapor deposition process using trimethylborazine as precursor and with H2, He, N2, and NH3, respectively, as auxiliary gas. These films deposited on Si(100) wafers or fused quartz glass substrates were characterized
chemically by X-ray photoelectron spectroscopy and by synchrotron radiation-based total-reflection X-ray fluorescence combined
with near-edge X-ray absorption fine structure. Independent of the auxiliary gas, the B–N bonds are dominating. Furthermore,
B–C and N–C bonds were identified. Oxygen, present in the bulk (in contrast to the surface layer of some nanometers, where
molecular oxygen and/or water are absorbed) as an impurity, is bonded to boron or to carbon, respectively. The relation of
boron and nitrogen changes with the character of the auxiliary gas: c
B/c
N ≈ 4:3 (for H2 and He) and c
B/c
N ≈ 1 (for N2 or NH3). Furthermore, physical properties such as the refractive index and the optical band-gap energy were determined. 相似文献
2.
Andreas Gupper Asunción Fernández Christina Fernández-Ramos Ferdinand Hofer Christian Mitterer Peter Warbichler 《Monatshefte für Chemie / Chemical Monthly》2002,41(3):837-848
Superhard nanocomposite coatings of different composition in the quasi-binary system TiN–TiB2 were deposited onto stainless steel sheets by means of unbalanced DC magnetron co-sputtering using segmented TiN/TiB2 targets. The chemistry and microstructure of a TiB0.6N0.7 coating was investigated using X-ray and electron diffraction, photoelectron spectroscopy, energy-filtering transmission electron microscopy, and electron energy-loss spectrometry. High resolution elemental mapping of the elements Ti, B, N, and O with energy-filtering TEM reveals a homogeneous distribution on the nanometer scale. X-Ray and electron diffraction exhibit only TiN crystallites of nanometer size, but no information on the boron-rich phase. The near-edge fine structures of the BK and NK ionization edges in the EELS spectra of the Ti–B–N coatings were used to derive information on the phases by comparing the edges with those of reference compounds. It was found that the TiN nanocrystals occur together with TiO x particles; the grains are embedded in a strongly disordered or quasi-amorphous matrix consisting mainly of TiB2 particles and, near the steel substrate, also boron oxide (B2O3). 相似文献
3.
Andreas Gupper Asunción Fernández Christina Fernández-Ramos Ferdinand Hofer Christian Mitterer Peter Warbichler 《Monatshefte für Chemie / Chemical Monthly》2002,133(6):837-848
Summary. Superhard nanocomposite coatings of different composition in the quasi-binary system TiN–TiB2 were deposited onto stainless steel sheets by means of unbalanced DC magnetron co-sputtering using segmented TiN/TiB2 targets. The chemistry and microstructure of a TiB0.6N0.7 coating was investigated using X-ray and electron diffraction, photoelectron spectroscopy, energy-filtering transmission
electron microscopy, and electron energy-loss spectrometry. High resolution elemental mapping of the elements Ti, B, N, and
O with energy-filtering TEM reveals a homogeneous distribution on the nanometer scale. X-Ray and electron diffraction exhibit
only TiN crystallites of nanometer size, but no information on the boron-rich phase. The near-edge fine structures of the
BK and NK ionization edges in the EELS spectra of the Ti–B–N coatings were used to derive information on the phases by comparing the
edges with those of reference compounds. It was found that the TiN nanocrystals occur together with TiO
x
particles; the grains are embedded in a strongly disordered or quasi-amorphous matrix consisting mainly of TiB2 particles and, near the steel substrate, also boron oxide (B2O3).
Received October 4, 2001. Accepted (revised) January 10, 2002 相似文献
4.
The reaction of N-benzoylphosphoramidic dichloride with amines afforded some new N-benzoylphos-phoric triamides with formula C6H5C(O)NHP(O)(X)2, X=NH–CH(CH3)2 (1), NH–CH2–CH(CH3)2 (2), NH–CH2–CH(OCH3)2 (3), N(CH3)[CH2CH(OCH3)2] (4) and N(CH3)(C6H11) (5) that were characterized by 1H,13C,31P NMR, IR spectroscopy and elemental analysis. The structures have been determined for compounds 4 and 5 by X-ray crystallography. These compounds contain one amidic hydrogen atom and form centrosymmetric dimmers via intermolecular
–P–O⋯H–N–hydrogen bonds besides weak C–H⋯O hydrogen bonds that lead to three-dimensional polymeric clusters in the crystalline
lattice. 相似文献
5.
Jessie Casimiro Bénédicte Lepoittevin Caroline Boisse-Laporte Marie-Geneviève Barthés-Labrousse Pascale Jegou Fran?ois Brisset Philippe Roger 《Plasma Chemistry and Plasma Processing》2012,32(2):305-323
With the aim of introducing primary amino groups on the surface of poly(ethylene terephthalate) (PET), two methods were compared—the
use of ammonia or a combination of nitrogen and hydrogen low-pressure microwave plasma. Several plasma parameters were optimized
on the reactor to increase the –NH2 surface density, which was estimated by colorimetric titration and X-ray photoelectron spectroscopy (XPS). These techniques
show that whatever the plasma treatment, almost 2 –NH2/nm2 are incorporated on PET films. Emission spectroscopy highlighted a correlation between the density of primary amino groups
and the ratio between an NH peak intensity and an Ar peak intensity (INH/IAr). Variation in surface hydrophilicity with aging in air after plasma treatment was monitored with contact angle measurements
and showed a hydrophobic recovery. This was confirmed by XPS, which suggests also that surfaces treated by NH3 plasma are more stable than surfaces treated by N2/H2. 相似文献
6.
Hui Li Jinshu Wang Hongyi Li Shu Yin Tsugio Sato 《Research on Chemical Intermediates》2010,36(1):27-37
Nitrogen and sulfur co-doped mesoporous TiO2 thin films were fabricated using thiourea as a doping resource by the combination of the sol–gel and evaporation-induced
self-assembly (EISA) processes. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy
(XPS), N2 adsorption–desorption, and UV–vis spectra were performed to characterize the as-synthesized mesoporous TiO2 materials. The XPS result shows that O–Ti–N and O–Ti–S bonds in the (S, N)-codoped mesoporous TiO2 were formed. The resultant mesoporous (S, N)-codoped TiO2 exhibited anatase framework with a high porosity and a narrow pore distribution. After being illuminated for 3 h, methyl
orange (MO) could be degraded completely by the co-doped sample under the ultraviolet irradiation, whereas mesoporous TiO2 film without doping could only degrade 60% MO. After being illuminated by visible light, the water contact angles of the
mesoporous co-doped TiO2 samples decreased slightly, but the pure TiO2 mesoporous film exhibited no change in the hydrophilicity. 相似文献
7.
Zusammenfassung Bei der Aminoborierung von Carbonylsulfid erfolgt 1,2-Addition an die Carbonylgruppe, wobei in Tris(dimethylamino)boran zwei der B–N-Bindungen, in Bis(dimethylamino)chlorboran nur eine B–N-Bindung reagieren. In Tris(2,2-dimethylhydrazino)boran reagieren alle drei B–N-Bindungen mit CO2; mit CS2 erfolgt unter den gleichen Bedingungen keine Reaktion. Mit Phosgen und Thiophosgen reagiert Tris(dimethylamino)boran unter Bildung von Bis(dimethylamino)chlorboran und substituierter Carbamide.
Reactions of aminoboranes and hydrazinoboranes with carbonyl and thiocarbonyl compounds
Upon aminoboration of carbonyl sulfide 1,2-addition to the carbonyl group is observed. In tris(dimethylamino)borane insertion into two of the B–N bonds occurs, while in bis(dimethylamino)chloroborane only one B–N bond reacts with OCS. In tris(2,2-dimethylhydrazino)borane all three B–N bonds react with CO2, while with CS2 no insertion reaction is observed under comparable conditions. Tris(dimethylamino)borane reacts with phosgene and thiophosgene with formation of bis(dimethylamino)chloroborane and substituted carbamides.相似文献
8.
K Sivashankar 《Journal of Chemical Sciences》2000,112(6):607-614
Hydrogen bonded complexes of cyanuric acid (CA) with pyridine, [C3N3H3O3:C5H5N], 1, and guanidinium carbonate [C3H2N3][C(NH2)3],2, have been prepared at room temperature and characterized by single-crystal X-ray diffraction. Structure of 1 shows pyridine
molecules substituting the inter-tape hydrogen bond in CA by N-H… N and C-H…O hydrogen bonds. The structure reveals CA-pyridine
hydrogen-bonded single helices held together by dimeric N-H…O hydrogen bonding between CA molecules. In2, the CA tapes, resembling a sine wave interact with the guanidinium cations through N-H…O and N-H…N hydrogen bonds forming
guanidinium cyanurate sheets. 相似文献
9.
Mahmut Ulusoy Hasan Karabıyık Rafet Kılınçarslan Muhittin Aygün Bekir Çetinkaya Santiago García-Granda 《Structural chemistry》2008,19(5):749-755
Copper(II) and cobalt(II) complexes of salicylaldimine obtained by the condensation of N,N-diethyl-2-methyl-1,4-phenylenediamine with 3,5-di-tert-butyl-2-hydroxybenzaldehyde have been synthesized and characterized by elemental analyses, magnetic susceptibility measurements,
cyclic voltammetry, and FT-IR and UV–Vis spectroscopy. The molecular structure of the title copper(II) complex was determined
by the single crystal X-ray diffraction technique. The Cu(II) center is coordinated by four atoms of the donor set in a compressed
tetrahedral trans-[N2O2] environment, which can be essentially ascribed to the presence of bulky fragments of the ligand. The computed bond valences
of the copper verify +2 oxidation state and indicate that the copper bonds, in particular Cu–N bonds, are elongated due to
steric effects from bulky substituents in the ligands, N-(4-diethylamino-2-methylphenyl). Intermolecular C–H···π interactions leading to centrosymmetric synthons serve to stabilize
periodic organization of the molecules. 相似文献
10.
Longhua Yang Xingye Ren Hongming Wang Ning Zhang Sanguo Hong 《Research on Chemical Intermediates》2012,38(1):113-133
Density functional theory calculations have been carried out to explore the reaction mechanisms for the reactions of “frustrated
Lewis pairs” (FLPs) with small molecules. Four reactions were studied in the present investigation. A new N-heterocyclic carbene borane, boron amidinate compound HC(iPrN)2B(C6F5)2 (1), classified as FLPs, was chosen as the common reactant of these reactions. It was used to react with CO2, CO, and two terminal alkynes, methylacetylene and phenylacetylene. The reactions of 1 with CO2 and CO can both be regarded as the concerted addition mechanisms. In these reactions, the formations of the C2–N2 and B–O1
bonds take place simultaneously. For the reactions of 1 and methylacetylene or phenylacetylene, our calculations indicated that a deprotonation pathway and the connection between
B atoms and terminal alkyne C atoms occur by a concerted manner simultaneously, together with the connection between N2 and
hydrogen atoms. We also investigated the reaction mechanisms according to the frontier molecular orbital (FMO) theory and
carried out electric charge analyses, finding that the two results were consistent with each other perfectly. Electric charges
transfer from HOMO of 1_OPEN to LUMO of CO2 or CO. In contrast, electric charges transfer from HOMO of methylacetylene or phenylacetylene to LUMO of 1_OPEN. 相似文献
11.
E. A. Malinina V. V. Drozdova L. V. Goeva I. N. Polyakova N. T. Kuznetsov 《Russian Journal of Inorganic Chemistry》2007,52(6):854-858
A new binuclear cadmium(II) complex with neutral ligands, 1,2-diaminobenzene (DMB) and dimethylformamide (DMF), [Cd2(Ph(NH2)2)5(DMFA)4](B10H10)2, was synthesized and studied by IR spectroscopy and X-ray diffraction. The crystals are monoclinic, a = 26.198(3) ?, b = 12.742(3) ?, c = 21.658(3) ?, β = 119.985(10)°, Z = 8, space group C2/c. The distorted octahedral environment of Cd is formed by four nitrogen atoms of three DAB molecules and two oxygen atoms
of DMF molecules. Three independent DAB molecules perform different functions: one chelates the Cd atom, another is linked
to cadmium as a monodentate ligand, and the third one bridges two Cd atoms, thus forming the dimer. The amino groups of the
DAB molecules are involved in the N-H⋯O and N-H⋯N hydrogen bonds and in N-H⋯B and N-H⋯H-B specific interactions with the cluster
boron anion.
Original Russian Text ? E.A. Malinina, V.V. Drozdova, L.V. Goeva, I.N. Polyakova, N.T. Kuznetsov, 2007, published in Zhurnal
Neorganicheskoi Khimii, 2007, Vol. 52, No. 6, pp. 922–926. 相似文献
12.
Masoud Nazarian-Samani Ali Reza Kamali Mahboobeh Nazarian-Samani Roohallah Mobarra Saber Naserifar 《Journal of Thermal Analysis and Calorimetry》2012,107(1):265-269
A combination of differential thermal analysis and detailed X-ray diffraction (XRD) analyses were used for the thermokinetic
study of phase evolution during heating–cooling of the mechanically alloyed (MA-ed) Ni–15 wt% B. According to the results
obtained, different phase transition sequences led to the formation of nanocrystalline Ni–B alloys comprising of Ni2B + o-Ni4B3 and Ni2B + m-Ni4B3 + B. Using the XRD studies, it was found that the Ni2B is the most stable intermetallic compound in the Ni–B binary phase diagram, and its nanocrystalline nature retained unchanged
even after annealing up to temperatures near the melting point. In addition, average enthalpy as well as activation energy
of occurred reactions was calculated; the latter was estimated using two well-known Kissinger and Augis & Bennett methods. 相似文献
13.
E. Melnic P. Bourosh A. Rija J. Lipkowski O. A. Bologa I. Bulhac E. Coropceanu V. N. Shafranski 《Russian Journal of Coordination Chemistry》2012,38(9):623-633
A number of new Co(III) dimethylglyoximates containing N-pyrimidinylsulfanilamides were obtained. These complexes of the general formula [Co(N3)(DH)2L] (I?CV) (where DH is the dimethylglyoxime monoanion and L are N-pyrimidinylsulfanilamides NH2-C6H4-SO2-NH-R with different substituents R) are expected to have antibacterial properties. Their structures were examined by IR, electronic absorption, and NMR spectroscopy and X-ray diffraction. They were classified among cobalt(III) trans dioximates. In all the complexes obtained, the cobalt atom coordinates to four N atoms of two dimethylglyoxime residues. The octahedral environment of the metal atom is completed with the amino N atom of the neutral molecule L and the N atom of the azide anion. In the crystal structures, complexes I?CV are united through intermolecular hydrogen bonds N-H??O, N-H??N, and O-H??O, in which the groups ?NH2 and =NH of the ligand L and water molecules (for I, IV, and V) serve as proton donors. 相似文献
14.
A. E. Panasenko L. A. Zemnukhova V. Ya. Kavun E. B. Merkulov 《Russian Journal of Inorganic Chemistry》2012,57(2):163-168
Complexes of the formula MSb2BrF4O (M = K, Rb, and NH4) were obtained from aqueous solutions of SbF3 and MBr and examined by chemical analysis, X-ray diffraction, thermal analysis, and IR, Raman, and 19F NMR spectroscopy. It was found that the red reflectance is 74–97% and the UV reflectance is 7–15%. The highest averaged
reflectance (93%) was observed for KSb2BrF4O. The decomposition temperatures of MSb2BrF4O (M = K, Rb, and NH4) are 230, 197, and 223°C, respectively. 相似文献
15.
16.
Sheng-Feng Hong Xiao-Huan Liang Hua-Cai Fang Xu-Lin Zhan Zheng-Yuan Zhou Li Chen Yue-Peng Cai 《Transition Metal Chemistry》2009,34(1):115-120
Two mononuclear complexes with the Schiff base ligand 2-((2-(dimethylamino)ethylimino)methyl)phenol (HL), namely ZnL2 and CoL2(N3), have been synthesized and characterized using single-crystal X-ray diffraction and spectroscopy (IR, 1H NMR, UV–Vis, MS and EA). Both complexes are mononuclear. The coordination geometry in the Zn(II) complex is distorted square-pyramidal
with a weak Zn···N interaction. The Co(III) complex is distorted octahedral, and the neutral molecule unit [CoIIIL2(N3)] is connected by C–H···N hydrogen bonds to form a one-dimensional infinite chain. The luminescence of the zinc compound
has been investigated.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
17.
Francisco Pérez-García Antonio R. Tapia-Benavides Hugo Tlahuext Alejandro Álvarez Margarita Tlahuextl 《Structural chemistry》2006,17(4):359-366
This paper describes the structural studies of 2-phenyl-9,9′-dimethyl-2,2′-spirobis(1,3,2-λ5-benzoxazarsoline) 5, 2-phenyl-8,8′-dimethyl-2,2′-spirobis(1,3,2-λ5-benzoxazarsoline) 6 by 1H,13C,15N NMR in [2H6]DMSO and CDCl3. The solid state studies were made by X-ray experiments. Infrared spectroscopy was obtained in CDCl3 and the vibrational signals were assigned using DFT calculations. The nature of the As–N, As–C and As–O bonds in these compounds was established by NBO studies. 相似文献
18.
《Radiation Physics and Chemistry》2007,76(6):941-950
In this study, plasma-polymerized thin films were prepared from plasma enhanced chemical vapor deposition (PECVD) of acetylene (C2H2), acetylene/nitrogen (C2H2/N2), or acetylene/ammonia (C2H2/NH3). When N2 or NH3 was mixed with C2H2 in the feed, the films were identified to contain all elements of the mixture and the properties of the films were implied by the C–H bonds and nitrogen functionalities. As shown by X-ray photoelectron spectroscopy (XPS) the [N]/[C] atomic ratio varies by changing the mixture composition and reaches a maximum of 0.12 for mixing C2H2 with NH3. It is found that the resistance of the thin film sensors prepared from C2H2, C2H2/N2, and C2H2/NH3 is distinctly decreased by over 2 orders of magnitude by the adsorption of ethanol vapor. 相似文献
19.
H. Sadaf S. Ahmad S. Sharif I. U. Khan M. Akkurt S. W. Ng M. I. Khan S. A. Bashir M. Mufakkar 《Journal of Structural Chemistry》2012,53(1):151-155
Two mercury(II) cyanide complexes of N-ethylthiourea (Ettu) and N-propylthiourea (Prtu) ligands, [Hg(Ettu)2(CN)2] (1) and [Hg(Prtu)2(CN)2] (2), were prepared and their crystal structures were determined by X-ray crystallography. In both structures, the mercury atom
is coordinated to two sulfur atoms of thioureas and two cyanide carbon atoms in a pseudo-tetrahedral mode with the bond angles
in the range of 90.52(11)–162.2(3)°. The structures are stabilized by N-H—S, N-H—N, and C-H—N intramolecular and intermolecular
hydrogen bonds. 相似文献
20.
M. M. Krayushkin M. A. Kalik D. L. Dzhavadov L. G. Vorontsova Z. A. Starikova A. Yu. Martynkin V. L. Ivanov B. M. Uzhinov 《Russian Chemical Bulletin》2000,49(10):1757-1762
A series of new photochromic compounds were obtained for the first time from 1,2-bis(2-ethylthio-3-thienyl)perfluorocyclopentene by substituting bromine atoms or carboxy, alkoxycarbonyl, and carbamoyl groups for hydrogen atoms in positions 4 and 4′. Introduction of these substituents causes a slight bathochromic shift (by 20–30 nm) of a long-wavelength absorption band for the cyclic form and significantly increases the quantum yields of photocyclization ФA→B and ring opening ФB→A. Depending on the nature of a substituent, ФA→B decreases in the order COOH>COOMe>CONHAr. The quantum yields are markedly reduced when the ethylthio groups in positions 5 and 5′ are replaced by ethylsulfonyl groups (a tenfold reduction in ФA→B and a four- to fivefold reduction in ФB→A) The most considerable bathochromic shift of a long-wavelength band and the highest quantum yields of forward and reverse photoreactions were observed for 1,2-bis(4-bromo-2-ethylthio-3-thienyl) perfluorocyclopentene. 1,2- Bis (2-ethyl-5-ethylthio-4-methoxycarbonyl-3-thienyl)perfluorocyclopentene was structurally characterized by X-ray diffraction analysis. 相似文献