Search results for "composites"
showing 10 items of 1905 documents
Competitive Profiling of Ligandable Cysteines in Staphylococcus aureus with an Organogold Compound
2022
With the idea of exploiting metal-templated reactions to achieve selective modification of cysteines in proteins for antibacterial applications, an organometallic cyclometalated Au(III) compound was explored in a competitive chemoproteomic approach based on the isoDTB-ABPP (isotopically labelled desthiobiotin azide-activity-based protein profiling) technology in S. aureus cell extracts. In this way, more than 100 ligandable cysteines where identified, of which 10 were close to functional sites of proteins encoded by essential genes indicating potential for antibiotic development. Interestingly, more than 50% of the identified ligandable sites were not engaged by organic α-chloroacetamides i…
Application of the theory of naturally curved and twisted bars to designing Gorlov's helical turbine 1. System of governing equations
1998
The method of designing a new type of turbine used in flows of various kinds is discussed. Static, kinematic, and constitutive equations for transversely isotropic naturally curved and twisted bars are given, and the hypotheses used are discussed. The statement of the problem is linear and corresponds to small displacements. A method for solving the statically indeterminate problem is proposed. The objectives of numerical calculations, which will comprise the content of the second part of the investigation, are formulated.
Nonlinear response functions in an exponential trap model
2014
The nonlinear response to an oscillating field is calculated for a kinetic trap model with an exponential density of states and the results are compared to those for the model with a Gaussian density of states. The calculations are limited to the high temperature phase of the model. It is found that the results are qualitatively different only in a temperature range near the glass transition temperature $T_0$ of the exponential model. While for the Gaussian model the choice of the dynamical variable that couples to the field has no impact on the shape of the linear response, this is different for the exponential model. Here, it is found that also the relaxation time strongly depends on the …
Water absorption and hydrothermal performance of PHBV/sisal biocomposites
2014
[EN] The performance of biocomposites of poly(hydroxybutyrate-co-valerate) (PHBV) and sisal fibre subjected to hydrothermal tests at different temperatures above the glass transition of PHBV (TH ¿ 26, 36 and 46 C) was evaluated in this study. The influences of both the fibre content and presence of coupling agent were focused. The water absorption capability and water diffusion rate were considered for a statistical factorial analysis. Afterwards, the physico-chemical properties of water-saturated biocomposites were assessed by Fourier-Transform Infrared Analysis, Size Exclusion Chromatography, Differential Scanning Calorimetry and Scanning Electron Microscopy. It was found that the water d…
Premature conclusions about the signal‐to‐noise ratio in structural equation modeling research : A commentary on Yuan and Fang (2023)
2023
In a recent article published in this journal, Yuan and Fang (British Journal of Mathematical and Statistical Psychology, 2023) suggest comparing structural equation modeling (SEM), also known as covariance-based SEM (CB-SEM), estimated by normal-distribution-based maximum likelihood (NML), to regression analysis with (weighted) composites estimated by least squares (LS) in terms of their signal-to-noise ratio (SNR). They summarize their findings in the statement that “[c]ontrary to the common belief that CB-SEM is the preferred method for the analysis of observational data, this article shows that regression analysis via weighted composites yields parameter estimates with much smaller stan…
Topologically Novel Multiple Rotaxanes and Catenanes Based on Tetraurea Calix[4]arenes
2006
Calix[4]arenes bearing at their wide rim four urea residues easily form hydrogen bonded dimeric capsules. This has been used to preorganise alkenyl functions attached to these urea groups for their controlled connection via metathesis reaction. Multimacrocyclic tetraurea derivatives are thus obtained in excellent yields via heterodimers which are formed exclusively with tetratosylurea derivatives. Heterodimerisation of such bis- and tetraloop tetraureas leads analogously to multicatenanes, or to rotaxanes by stoppering. Huge macrocycles are detached from tetraloop derivatives by cleavage of the urea function.
A heteropentanuclear oxalato-bridged [ReIV 4GdIII] complex: synthesis, crystal structure and magnetic properties
2012
The compound (NBu 4) 5[Gd III{Re IVBr 4(μ-ox)} 4(H 2O)]·H 2O (1), with intramolecular antiferromagnetic coupling, is the first Re(iv) system incorporating a 4f ion. © 2012 The Royal Society of Chemistry.
A Comparative Structural and Magnetic Study of Three Compounds Based on the Cluster Unit M4Cl8(THF)6 (M=Mn, Fe, Co)
2001
Treatment of anhydrous M Cl 2 phases with THF under refluxing conditions leads to excision of the clusters M 4 Cl 8 (THF) 6 ( M =Fe (1), Co (3)) and dimensional reduction to the chain of clusters, {Mn 4 Cl 8 (THF) 6 (Mn(THF) 2 Cl 2 } ∞ , (2). All three compounds were isolated in high yields as crystalline materials and subjected to comprehensive magnetic studies. X-ray structures of the three compounds were performed to verify the nature of the compounds, but only the Mn derivative is discussed in detail due to the fact that the structures of the Fe and Co clusters were reported earlier. The molecular structures of M 4 Cl 8 (THF) 6 ( M =Fe, Co) consist of a rhombic arrrangement of metal ion…
[FeIILSCoIIILS]2⇔ [FeIIILSCoIIHS]2 photoinduced conversion in a cyanide-bridged heterobimetallic molecular square
2010
The self-assembly of [Fe(III){B(pz)(4)}(CN)(3)](-) and [Co(II)(bik)(2)(S)(2)](2+) affords the diamagnetic cyanide-bridged [Fe(II)(LS)Co(III)(LS)](2) molecular square which is converted into the corresponding magnetic [Fe(III)(LS)Co(II)(HS)](2) species under light irradiation at relatively low temperatures.
Synthesis and crystal structure of an unprecedented bismuth porphyrin containing ester pendant arms
2000
International audience; An easily prepared porphyrin with pendant arms is shown to form a stable complex with bismuth(III) ion; the complex is eight coordinate with a square antiprismatic coordination geometry; the solid-state structure exhibits the formation of a dimer assembled via mutual coordination of a terminal ester group.