| 1. |
|
|
| 2. |
- Bousquet, J, et al.
(author)
-
Nrf2-interacting nutrients and COVID-19: time for research to develop adaptation strategies
- 2020
-
In: Clinical and translational allergy. - : Wiley. - 2045-7022. ; 10:1, s. 58-
-
Journal article (peer-reviewed)abstract
- There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPARγ:Peroxisome proliferator-activated receptor, NFκB: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2α:Elongation initiation factor 2α). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT1R axis (AT1R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Bosnic-Anticevich, S, et al.
(author)
-
ARIA pharmacy 2018 "Allergic rhinitis care pathways for community pharmacy"
- 2019
-
In: Allergy. European Journal of Allergy and Clinical Immunology. - : Wiley. - 0105-4538 .- 1398-9995. ; 74:7, s. 1219-1236
-
Research review (peer-reviewed)abstract
- Pharmacists are trusted health professionals. Many patients use over-the-counter (OTC) medications and are seen by pharmacists who are the initial point of contact of allergic rhinitis management in most countries. The role of pharmacists in integrated care pathways (ICPs) for allergic diseases is important. This paper builds on existing studies and provides tools intended to help pharmacists provide optimal advice/interventions/strategies to patients with rhinitis. The ARIA-pharmacy ICP includes a diagnostic questionnaire specifically focusing attention on key symptoms and markers of the disease, a systematic Diagnosis Guide (including differential diagnoses) and a simple flowchart with proposed treatment for rhinitis and asthma multimorbidity. Key prompts for referral within the ICP are included. The use of technology is critical to enhance the management of AR. However, the ARIA-pharmacy ICP should be adapted to local health care environments/situations as regional (national) differences exist in pharmacy care.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- Bousquet, J. Jean, et al.
(author)
-
Next-generation ARIA care pathways for rhinitis and asthma : a model for multimorbid chronic diseases
- 2019
-
In: Clinical and Translational Allergy. - : BMC. - 2045-7022. ; 9
-
Research review (peer-reviewed)abstract
- Background: In all societies, the burden and cost of allergic and chronic respiratory diseases are increasing rapidly. Most economies are struggling to deliver modern health care effectively. There is a need to support the transformation of the health care system into integrated care with organizational health literacy.Main body: As an example for chronic disease care, MASK (Mobile Airways Sentinel NetworK), a new project of the ARIA (Allergic Rhinitis and its Impact on Asthma) initiative, and POLLAR (Impact of Air POLLution on Asthma and Rhinitis, EIT Health), in collaboration with professional and patient organizations in the field of allergy and airway diseases, are proposing real-life ICPs centred around the patient with rhinitis, and using mHealth to monitor environmental exposure. Three aspects of care pathways are being developed: (i) Patient participation, health literacy and self-care through technology-assisted "patient activation", (ii) Implementation of care pathways by pharmacists and (iii) Next-generation guidelines assessing the recommendations of GRADE guidelines in rhinitis and asthma using real-world evidence (RWE) obtained through mobile technology. The EU and global political agendas are of great importance in supporting the digital transformation of health and care, and MASK has been recognized by DG Sante as a Good Practice in the field of digitally-enabled, integrated, person-centred care.Conclusion: In 20 years, ARIA has considerably evolved from the first multimorbidity guideline in respiratory diseases to the digital transformation of health and care with a strong political involvement.
|
|
| 10. |
- Bousquet, Jean, et al.
(author)
-
ARIA digital anamorphosis : Digital transformation of health and care in airway diseases from research to practice
- 2021
-
In: Allergy. European Journal of Allergy and Clinical Immunology. - : John Wiley & Sons. - 0105-4538 .- 1398-9995. ; 76:1, s. 168-190
-
Research review (peer-reviewed)abstract
- Digital anamorphosis is used to define a distorted image of health and care that may be viewed correctly using digital tools and strategies. MASK digital anamorphosis represents the process used by MASK to develop the digital transformation of health and care in rhinitis. It strengthens the ARIA change management strategy in the prevention and management of airway disease. The MASK strategy is based on validated digital tools. Using the MASK digital tool and the CARAT online enhanced clinical framework, solutions for practical steps of digital enhancement of care are proposed.
|
|
| 11. |
|
|
| 12. |
- Kritikos, M, et al.
(author)
-
Synthesis, structure and characterisation of Ln(5)O(OPri)(13) with Ln = Nd, Gd or Er
- 2001
-
In: JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS. - : Royal Society of Chemistry (RSC). - 1472-7773 .- 1364-5447. ; :13, s. 1931-1938
-
Journal article (peer-reviewed)abstract
- The molecular and basically isostructural oxo-alkoxides Ln(5)O(OPri)(13) (Pr-i = 2-propyl) with Ln = Nd (1) and Gd (2) were synthesized by metathesis of LnCl(3) and KOPri, in combination with stoichiometric hydrolysis, in 2-propanol-containing solvents. E
|
|
| 13. |
- Ma, G. B., et al.
(author)
-
Structure of the dimethyl sulfoxide solvated thallium(III) ion in solution and in the solid state
- 2001
-
In: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 40:25, s. 6432-6438
-
Journal article (peer-reviewed)abstract
- The structure and vibrational spectra of the dimethyl sulfoxide solvated thallium(III) ion have been studied in a dimethyl sulfoxide solution and in the solid state. X-ray crystallography shows a trigonal unit cell, space group R (3) over bar (No. 148), for the [TI(dmso)(6)](ClO4)(3) Compound with Z = 3, a = b = 11.9764(13) [11.8995(9)] Angstrom, c = 20.802(2) [20.467(2)] Angstrom, and V = 2584.0(5) [2509.9(4)] Angstrom (3) at 295 [150] K. The crystal structure comprises a highly symmetric hexakis(dimethyl sulfoxide)thallium(III) ion, with thallium in a 3 symmetry site and a TI-O bond distance of 2.224(3) Angstrom at 295 K. The octahedral TlO6 kernel is compressed along the threefold axis with an O-Tl-O bond angle of 96.20(11)degrees. The Tl-O-S bond angle of 120.7(2)degrees corresponds to a Tl . . .S distance of 3.292(2) Angstrom. One perchlorate ion centered on the (3) over bar axis was described by a statistically disordered model. A low-temperature EXAFS study (10 K) resulted in the TI-O and Tl . . .S distances of 2.221(4) and 3.282(6) Angstrom, respectively, consistent with a Tl-O-S bond angle of 120(1)degrees. The low Debye-Waller factors confirm a regular coordination without the disorder of the dimethyl sulfoxide ligands, which would have resulted from the alternative choice of space group R3 for the crystal structure. Raman and infrared spectra have been recorded and assigned, with the bands at 435 and 447 cm(-1) corresponding to the vibrational frequency of the symmetric and asymmetric TI-O stretching modes, respectively. EXAFS data of a 0.5 mol dm(-3) thallium(III) trifluoromethanesulfonate in a dimethyl sulfoxide solution were consistent with that of a hexasolvated ion with mean Tl-O and Tl . . .S distances of 2.22(1) and 3.33(2) Angstrom, respectively, which correspond to a mean Tl-O-S bond angle of 124(2)degrees. The anomalously large disorder parameter for the TI-O distances is consistent with a weal, pseudo-Jahn-Teller effect. The Tl-205, C-13, and H-1 NMR spectra of the complex in solution show single signals at 1886, 39.5, and 2.3 ppm, respectively.
|
|
| 14. |
- Jones, H. G., et al.
(author)
-
Examination of wear damage to rock-mining hardmetal drill bits
- 2017
-
In: International journal of refractory metals & hard materials. - : Elsevier BV. - 0263-4368. ; 66, s. 1-10
-
Journal article (peer-reviewed)abstract
- WC/Co mining bits from a drill head used for drilling holes for roof support bolts in a mine were examined using a focused ion beam scanning electron microscope (FIB-SEM). This was combined with energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) analyses to study the chemical interaction between the drill bit and the rock. It was found that at the surface of the buttons there was depletion of cobalt, change in chemistry of the remaining binder regions, and changes to the morphology of the WC grains. Tribochemistry calculations were done to understand the possible formation of silicides at the surface of the drill bits, and thus emphasise the importance of quartz content in rock on wear. The evidence of mechanical damage combined with chemical reactions is another step towards understanding the complete wear process in hardmetal mining tools.
|
|
| 15. |
|
|
| 16. |
- Ott, S., et al.
(author)
-
Model of the iron hydrogenase active site covalently linked to a ruthenium photosensitizer : Synthesis and photophysical properties
- 2004
-
In: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 43:15, s. 4683-4692
-
Journal article (peer-reviewed)abstract
- A model of the iron hydrogenase active site with the structure [(mu-ADT)Fe-2(CO)(6)] (ADT = azadithiolate (S-CH2-NR-CH2-S), (2: R = 4-bromophenyl, 3: R = 4-iodophenyl)) has been assembled and covalently linked to a [Ru(terpy)(2)](2+) photosensitizer. This trinuclear complex 1 represents one synthetic step toward the realization of our concept of light-driven proton reduction. A rigid phenylacetylene tether has been incorporated as the linking unit in 1 in order to prolong the lifetime of the otherwise short-lived [Ru(terpy)(2)](2+) excited state. The success of this strategy is demonstrated by comparison of the photophysical properties of 1 and of two related ruthenium complexes bearing acetylenic terpyridine ligands, with those of [Ru(terpy)(2)](2+). IR and electrochemical studies reveal that the nitrogen heteroatom of the ADT bridge has a marked influence on the electronic properties of the [Fe-2(CO)(6)] core. Using the Rehm-Weller equation, the driving force for an electron transfer from the photoexcited *[Ru(terpy)(2)](2+) to the diiron site in 1 was calculated to be uphill by 0.59 eV. During the construction of the trinuclear complex 1, n-propylamine has been identified as a decarbonylation agent on the [(mu-ADT)Fe-2(CO)(6)] portion of the supermolecule. Following this procedure, the first azadithiolate-bridged dinuclear iron complex coordinated by a phosphine ligand [(mu-ADT)Fe-2(CO)(5)PPh3] (4, R = 4-bromophenyl) was synthesized.
|
|
| 17. |
|
|
| 18. |
|
|
| 19. |
|
|
| 20. |
|
|
| 21. |
|
|
| 22. |
- Ivanov, Alexander V., et al.
(author)
-
Adduct formation of the zinc morpholinedithiocarbamate complex with morpholine as studied by CP/MAS 15N NMR and single-crystal X-ray diffraction
- 2004
-
In: Russian Journal of Inorganic Chemistry. - 0036-0236 .- 1531-8613. ; 49:12, s. 1863-1870
-
Journal article (peer-reviewed)abstract
- The adduct of the zinc morpholineditiohcarbamate complex with morpholine [Zn(Mf)(MfDtc)2] and its solvated form [Zn(Mf)(MfDtc) 2]·Mf were studied by CP/MAS 15N NMR and single-crystal X-ray diffraction. These complexes are molecular, and the dithiocarbamate ligands therein are structurally nonequivalent. Solvation of the adduct aggravates this nonequivalence. The molecular and crystal structure of [Zn(Mf)(MfDtc)2]·Mf was determined by X-ray crystallography. The crystal structure of this compound has a system of ordered channels accommodating the outer-sphere morpholine molecules of solvation, which points to the formation of clathrate structures. The zinc coordination polyhedron [ZnS4N] is a somewhat distorted square pyramid with the four sulfur atoms at the base and the nitrogen atom at the apex. The square-pyramidal (SP) (97%) and trigonal-bipyramidal (TBP) (3%) contributions to the geometry of the zinc polyhedron were calculated. The 15N NMR signals were assigned to the structural positions of the nitrogen atoms in the molecular structure determined
|
|
| 23. |
|
|
| 24. |
- Ivanov, Alexander V., et al.
(author)
-
Bis(diethyldithiocarbamato)pyridinezinc(II) and -copper(II) clathrates M(Edtc)2Py·nL (L = CH2Cl2 and CHCl3; n = 1 and 0.5) : Molecular and crystal structures and EPR and high-resolution solid-state (13C, 15N) NMR spectra
- 1999
-
In: Russian journal of coordination chemistry. - 1070-3284 .- 1608-3318. ; 25:8, s. 543-555
-
Journal article (peer-reviewed)abstract
- X-ray diffraction analysis, EPR, and high-resolution solid-state (13C, 15N) NMR spectroscopy were used to examine structural organization and spectral properties of six bis(diethyldithiocarbamato)pyridine-zinc(II) and copper(II) solvates with dichloromethane and chloroform, M(Edtc)2Py·nL (n = 1 and 0.5). Typical of the clathrate-type structures, the compounds are penetrated by the ordered molecular channels filled with chemically nonbonded chlorohydrocarbon molecules. At the molecular level, the geometry of coordination polyhedra of complexing atoms is intermediate between trigonal bipyramidal and square pyramidal (the contribution of the square-pyramidal component is quantitatively estimated for the zinc clathrate). Accordingly, the ground state of the unpaired electron in the copper(II) compounds is a combination of the dx2-y2 and dz2 orbitals. It is shown that the nonequivalence of the Edtc- ligands in zinc(II) clathrates manifests itself both magnetically and structurally. The chlorine atoms of the solvate dichloromethane molecules, unlike chloroform molecules, are disordered over the two structural positions with different multiplicities. The 13C and 15N NMR signals are assigned to the atomic positions in the resolved molecular structures
|
|
| 25. |
- Ivanov, Alexander V., et al.
(author)
-
Bis(diethyldithiocarbamato)pyridinezinc(II) and copper(II) clathrates with pyridine: Molecular structure and EPR and high-resolution solid-state (13C, 15N) NMR spectra
- 1998
-
In: Russian journal of coordination chemistry. - 1070-3284 .- 1608-3318. ; 24:9, s. 645-654
-
Journal article (peer-reviewed)abstract
- EPR, high-resolution solid-state (13C, 15N) NMR, and X-ray diffraction methods were used to study bis(diethyldithiocarbamato)pyridinezinc(II) and copper(II) clathrates with pyridine, M(EdIc)2Py · Py. The structural functionalities of the Py molecules in these clathrates were found to be different: one of them is coordinated to the complexing atom, while the other (solvate) is hydrogen-bonded to the sulfur atom of one of the ligands. The heterocycle of the uncoordinated Py molecule was found to be geometrically distorted. The structures of the copper and zinc coordination polyhedra are close to trigonal-bipyramidal: two sulfur atoms and the nitrogen atom of pyridine form the equatorial plane; another two sulfur atoms occupy axial positions at larger distances. EPR spectra of the magnetically diluted copper(II) clathrate exhibit well-resolved SHFS from the nitrogen atom of Py, owing to the contribution of the dz2 orbital to the ground-state wave function of the unpaired electron. The NMR data suggest that the nitrogen atoms of the Edtc- ligands are magnetically inequivalent and that the 15N chemical shift of the uncoordinated Py molecule changes in an unusual fashion. Signal assignment was carried out for the experimental 13C and 15N NMR spectra
|
|
| 26. |
- Ivanov, Alexander V., et al.
(author)
-
Clathrate Formation of Bis(diethyldithiocarbamato)pyridinezinc(II) and Bis(diethyldithiocarbamato)pyridinecopper(II) with Benzene by EPR, High-Resolution Solid-State 13C and 15N NMR, and X-ray Crystallography
- 1998
-
In: Russian Journal of Inorganic Chemistry. - 0036-0236 .- 1531-8613. ; 43:9, s. 1368-1376
-
Journal article (peer-reviewed)abstract
- The structures of the clathrates of bis(diethyldithiocarbamato)pyridinezinc(H) and-copper(II) with benzene were studied by EPR, high-resolution solid-state 13C and 15N NMR, and X-ray crystallography. The geometry of the coordination polyhedra in the clathrates M(EDtc)2· Py · C6H6is close to trigonal-bipyramidal. Two short M-S bonds and the M-N bond form the equatorial plane, and two long M-S bonds point toward the axial positions. For the magnetically diluted copper(II) clathrate, the hyperfine structure can be observed at low temperatures due to the nitrogen atom of pyridine, which is associated with the contribution of the dz2orbital to the ground-state wave function of the unpaired electron. The 13C and 15N NMR signals were assigned.
|
|
| 27. |
- Ivanov, Alexander V., et al.
(author)
-
Structural Organization of Symmetrical Dialkylthiuram Disulfides and Their Cyclic Analogs: X-Ray Diffraction and CP/MAS (13C, 15N) NMR Studies
- 2003
-
In: Russian journal of coordination chemistry. - 1070-3284 .- 1608-3318. ; 29:2, s. 142-150
-
Journal article (peer-reviewed)abstract
- High-resolution 13C and 15N solid-state NMR spectra were recorded for seven crystalline tetraalkyl-thiuram disulfides and their cyclic analogs of the general formula [R2NC(S)S]2 (where R = CH3, C2H5, C3H7, and i-C3H7 or R2 = (CH2)5, (CH2)6, and (CH2)4O). The 15N and 13C NMR resonances were assigned to the particular atoms in the compounds studied. Different isotropic 15N chemical shifts for both dialkyldithiocarbamato groups were interpreted while considering the inductive effects of the alkyl substituents combined with the mesomeric effect of the dithiocarbamato group. X-ray diffraction data were used to refine the molecular structure of bis(cyclohexamethylene)thiuram disulfide and to quantitatively characterize the conformations of the seven-membered N(CH2)6 heterocycles.
|
|
| 28. |
|
|
| 29. |
|
|
| 30. |
- Ivanov, Alexander V., et al.
(author)
-
Structure, EPR, and 13C and 15N NMR of Clathrates of Bis(diethyldithiocarbamato)pyridinezinc(II) and Bis(diethyldithiocarbamato)pyridinecopper(II) with 1,2-Dichloroethane
- 1999
-
In: Russian Journal of Inorganic Chemistry. - 0036-0236 .- 1531-8613. ; 44:10, s. 1605-1614
-
Journal article (peer-reviewed)abstract
- The structural organization of the clathrates of bis(diethyldithiocarbamato)pyridinezinc(II) and -copper(II) with 1,2-dichloroethane, M(Edtc)2Py · L, was studied by EPR, high-resolution solid-state 13C and 15N NMR, and X-ray crystallography. The clathrates contain typical molecular channels and cavities, which accommodate chemically unbound dichloroethane molecules. At the molecular level, the geometry of the zinc and copper coordination polyhedra is intermediate between a trigonal bipyramid and a square pyramid. The ground state of the unpaired electron of copper(II) is a result of mixing the dx2-y2 and dz2 orbitals. The Edtc ligands incorporated in the zinc(II) clathrate are somewhat nonequivalent, both magnetically and structurally. The chlorine atoms of the 1,2-dichloroethane molecule are disordered over two structural positions with different occupancies, which may point to the occurrence of several conformations. The 13C and 15N NMR signals were assigned based on combined analysis of available structural and NMR data
|
|
| 31. |
|
|
| 32. |
- Kaplan, B., et al.
(author)
-
Study of tool wear and chemical interaction during machining of Ti6Al4V
- 2018
-
In: International journal of refractory metals & hard materials. - : Elsevier BV. - 0263-4368. ; 72, s. 253-256
-
Journal article (peer-reviewed)abstract
- The present study concerns an investigation of the wear on three uncoated cemented carbide grades, with differing binder content and grain size, during longitudinal turning of Ti6Al4V as a function of cutting speed. The creater wear at end of tool life is studied in detail using electron microscopy and X-ray diffraction. It is observed that decreasing binder content results in slower wear progression and longer tool life. The microstructure of the adhered layer is also dependent on the binder content, where a lower amount of binder results in an increase of dark precipitates in the adhered layer. X-ray diffraction confirms the presence of bcc-W as a chemical wear product at the interface. Diffraction peaks corresponding to cubic (Ti,V)C are also occasionally observed.
|
|
| 33. |
|
|
| 34. |
|
|
| 35. |
- Kritikos, M., et al.
(author)
-
Novel bis(diethylenetriamine)thallium(III) complex. Synthesis and characterization in pyridine solution and in solid
- 2002
-
In: Inorganica Chimica Acta. - 0020-1693 .- 1873-3255. ; 331, s. 224-231
-
Journal article (peer-reviewed)abstract
- A new complex of thallium(ill) with the nitrogen donor ligand diethylenetriamine (dien) has been prepared and characterized by multinuclear NMR (H-1, C-13. Tl-205), infrared and Raman spectroscopy. and X-ray diffraction. In solution, the symmetric s-facial isomer of [Tl(dien)(2)](3+) is formed. This is a fluxional molecule even at low temperature (235 K): therefore, the different rotamers cannot be observed separately. A complete characterization of the complex is given from its non-trivial NMR spectra. The crystal structure of [Tl(dien)(2)](ClO4)(3).H2O shows u-facial geometry. where the coordination environment around thallium can be described as a distorted trigonal prism.
|
|
| 36. |
|
|
| 37. |
|
|
| 38. |
- Ma, Gui-Bin, et al.
(author)
-
Modification of binuclear Pt-Tl bonded complexes by attaching bipyridine ligands to the thallium site
- 2004
-
In: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 43:14, s. 4328-4340
-
Journal article (peer-reviewed)abstract
- Complex formation of monomeric thallium(III) species with 2,2'-bipyridine (bipy) in dimethyl sulfoxide (dmso) and acetonitrile solutions was studied by means of multinuclear (H-1, C-13, and (TI)-T-205) NMR spectroscopy. For the first time, NMR signals of the individual species [TI(bipy)(m)(SoIV)](3+) (M = 1-3) were observed despite intensive ligand and solvent exchange processes. The tris(bipy) complex was crystallized as [TI(biPY)(3)(dmso)](ClO4)(3)(dMSO)(2) (1), and its crystal structure determined. In this compound, thallium is seven-coordinated; it is bonded to six nitrogen atoms of the three bipy molecules and to an oxygen atom of dmso. Metal-metal bonded binuclear complexes [(NC)(5)Pt-TI(CN)(n)(SoIV)](n-) (n = 0-3) have been modified by attaching bipy molecules to the thallium atom. A reaction between [(NC)(5)Pt-TI(dMSO)(4)](s) and 2,2'-bipyridine in dimethyl sulfoxide solution results in the formation of a new complex, [(NC)(5)Pt-TI(bipy)(solv)]. The presence of a direct Pt-TI bond in the complex is convincingly confirmed by a very strong one-bond Pt-195-(TI)-T-205 spin-spin coupling ((1)J((195)pt-(TI)-T-205) = 64.9 kHz) detected in both Pt-195 and (TI)-T-205 NMR spectra. In solutions containing free cyanide, coordination of CN- to the thallium atom occurs, and the complex [(NC)(5)Pt-TI(bipy)(CN)(solv)](-) ((1)J(Pt-195-(TI)-T-205) = 50.1 kHz) is formed as well. Two metal-metal bonded compounds containing bipy as a ligand were crystallized and their structures determined by X-ray diffractometry: [(NC)(5)Pt-TI(bipy)(dMSO)(3)] (2) and [(NC)(5)Pt-TI(biPY)(2)] (3). The Pt-TI bonding distances in the compounds, 2.6187(7) and 2.6117(5) Angstrom, respectively, are among the shortest reported separations between these two metals. The corresponding force constants in the molecules, 1.38 and 1.68 N/cm, respectively, were calculated using Raman stretching frequencies of the Pt-TI vibrations and are characteristic for a single metal-metal bond. Electronic absorption spectra were recorded for the [(NC)(5)Pt-TI(bipy)(m)(solv)] compounds, and the optical transition was attributed to the metal-metal bond assigned.
|
|
| 39. |
- Ma, G. B., et al.
(author)
-
Small platinum-thallium clusters stabilized by ethylenediamine, (NC)(5)Pt-Tl(en)(n-1) (n=1-3) - Characterization in solution and in the solid state
- 2001
-
In: European Journal of Inorganic Chemistry. - 1434-1948 .- 1099-1948. ; :5, s. 1311-1319
-
Journal article (peer-reviewed)abstract
- Three neutral binuclear platinum-thallium compounds containing a direct and naked (unsupported by ligands) metal-metal bond have been prepared in dimethyl sulfoxide (DMSO). The compounds have the formula [(NC)(5)Pt-Tl(en)(n-1)] (n = 1-3, for compounds 1, 2 and 3, respectively) and were found to exist in solution by means of multinuclear NMR (Pt-195, Tl-205, C-13 and H-1) and Raman spectroscopy. The compounds exhibit very large single bond Pt-195-Tl-205 spin-spin coupling constants of 48-66 kHz. In addition, the solid state analogues of 1 and 3, [(NC)(5)Pt-Tl(DMSO)(4)](DMSO) and [(NC)(5)Pt-Tl(en)(2)]-(DMSO)(2), were synthesized and their structures determined by single crystal X-ray diffraction. The metal-metal bond lengths of Pt-Tl are 2.6131(4) Angstrom and 2.6348(5) Angstrom in compounds I and 3, respectively. Crystal data for compound 1: monoclinic, space group Cc (No. 9), Z = 4, a = 17.2367(14), b = 9.5560(11), c = 17.7941(15) Angstrom, beta = 100.551(10)9 V = 2881.4(5) Angstrom (3), T = 110(1) K; and for compound 3: monoclinic, space group P2(1) (No. 4), Z = 2, a 9.3167(14), b 12.3007(13), c = 11.4586(16) Angstrom, beta = 112.318(16)degrees, V =1214.8(3) Angstrom (3), T = 110(1) K.
|
|
| 40. |
- Odelros, S., et al.
(author)
-
Experimental and theoretical study of the microscopic crater wear mechanism in titanium machining
- 2017
-
In: Wear. - : Elsevier BV. - 0043-1648 .- 1873-2577. ; 376, s. 115-124
-
Journal article (peer-reviewed)abstract
- Continuous turning of Ti6AI4V with uncoated WC-Co cutting tool inserts mainly results in crater wear on the rake face of the tool. The crater is located close to the cutting edge and increases in size with increased time in cut. The flank wear remains minor until the point when the crater reaches a critical size so that the edge deforms plastically and edge breakage occurs. To understand the crater wear degradation mechanisms, this study focuses on examining the worn tool at different stages, using both experimental and theoretical techniques, as well as under static and dynamic conditions. A layer of adhered work-piece material is observed in the crater. The present study shows both experimental and theoretical evidence of carbon depletion of the WC in the crater and formation of W (bcc) at the interface during wet continuous longitudinal turning of Ti6AI4V. This has been demonstrated for the first time. In addition, indications of a carbon rich compound, possibly MC, where M=Ti, V and W, are also observed. These observations are verified by simulation of the diffusion process. Furthermore, diffusion simulations indicate that a liquid may form at the tool/chip interface in the crater zone during machining. Turning is a dynamic process, however, to study the chemical driving forces in this system under static conditions, a means of verification of which phases will form is needed. Therefore, a diffusion couple consisting of the same materials is prepared and analyzed. Similar results are obtained for the diffusion couple as for the worn tool, indicating that the chemical wear is an important degradation parameter. The diffusion couple results are also compared to a numerical simulation of the diffusion process.
|
|
| 41. |
|
|
| 42. |
|
|
| 43. |
|
|
| 44. |
|
|
| 45. |
|
|
| 46. |
- Salyi, S., et al.
(author)
-
Synthesis of an amino-functionalized model of the Fe-only hydrogenase active site
- 2003
-
In: Chemistry - A European Journal. - : Wiley. - 0947-6539 .- 1521-3765. ; 9:2, s. 557-560
-
Journal article (peer-reviewed)abstract
- A dinuclear 2Fe2S mimic 6 of the active site of the Fe-only hydrogenases has been synthesized. Complex 6 contains a free amino group which enables linkage to a protein backbone or to a redox active species for the study of electron transfer processes in proteins or in supramolecular systems. The structures of the complex 6 and its Boc-protected precursor 5 could be verified by X-ray crystallography.
|
|
| 47. |
- Schmitt, H., et al.
(author)
-
Synthesis, redox properties, and EPR spectroscopy of manganese(III) complexes of the ligand N,N-bis(2-hydroxybenzyl)-N '-2-hdroxybenzylidene-1,2-diaminoethane : Formation of mononuclear, dinuclear, and even higher nuclearity complexes
- 2002
-
In: Chemistry - A European Journal. - 0947-6539 .- 1521-3765. ; 8:16, s. 3757-3768
-
Journal article (peer-reviewed)abstract
- The synthesis and characterization of the title trisphenolate ligand are described. From its reaction with manganese(iii) three complexes were isolated. The crystal structures revealed one pentacoordinate monomer and two similar dimers with different solvents of crystallization. In the dimers the metal ions are hexacoordinate and connected through bridging of two phenolates. A combination of electrochemistry and EPR spectroscopy showed that, in acetonitrile, the isolated batches were all identical and mainly monomeric, indicating that the mononuclear complex is in equilibrium with the dimer and perhaps also with complexes of higher nuclearity, as suggested by the detection of both the trimer and the tetramer by electrospray ionization mass spectrometry (ESI-MS). The successful use of the monomer batch as an epoxidation catalyst indicated that a high-valent manganese-oxo species can be formed, although it is probably short-lived. This is also suggested by EPR studies of the species formed by electrochemical oxidation of the complex. Upon one-electron oxidation, a manganese(iv) species was formed, which was at least partly converted to another species containing a phenoxy radical.
|
|
| 48. |
- Weidow, J., et al.
(author)
-
Impact of crystal defects on the grain growth of cemented carbides
- 2018
-
In: International journal of refractory metals & hard materials. - : Elsevier Ltd. - 0263-4368 .- 2213-3917. ; 72, s. 199-202
-
Journal article (peer-reviewed)abstract
- Two different WC-Co powder mixtures were produced through a 200 h milling process. One of these mixtures were heat treated with the aim to remove the crystal defects from the WC grains. Image analysis showed that the two powders had the same average WC grain size and grain size distributions. X-ray diffraction showed much more narrow peaks for the material produced from the heat treated powder thus interpreted to have much less crystal defects. The powder mixtures were used to produce cemented carbides. Image analyses showed a clear difference for the WC grain sizes where the material produced from the heat treated powder had a significantly smaller mean WC grain size. It is therefore concluded that the crystal defects are of importance and facilitate WC grain growth during sintering.
|
|
| 49. |
|
|
| 50. |
- Yang, X. C., et al.
(author)
-
Axial ligand exchange reaction on ruthenium phthalocyanines
- 2005
-
In: Journal of Porphyrins and Phthalocyanines. - 1088-4246 .- 1099-1409. ; 9:4, s. 248-255
-
Journal article (peer-reviewed)abstract
- Bis(4-methylpyridine)phthalocyaninato ruthenium(II) has been synthesized. It was proved by single-crystal X-ray diffraction that the central Ru(II) atom is bonded to six N atoms in an elongated octahedral configuration, and the axial ligands have a significantly longer Ru-N bond distance, 2.101(4) angstrom, than the independent pyrrol Ru-N bond, 1.99 angstrom. Therefore, the axial ligands can be exchanged by other ligands. The ligand exchange reactions with diethyl pyridyl-4-phosphonate and diethyl pyridylmethyl-4-phosphonate were studied in high boiling-point solvents at elevated temperatures, ca 160 degrees C. Mono-ligand as well as double-ligand replaced complexes were obtained. The complexes have been isolated by column chromatography. These complexes have potential applications, such as in dye sensitized solar cells.
|
|
