<p>We thoroughly benchmark
time-dependent density- functional theory for the predictive calculation of
UV/Vis spectra of porphyrin derivatives. With the aim to provide an approach
that is computationally feasible for large-scale applications such as
biological systems or molecular framework materials, albeit performing with
high accuracy for the Q-bands, we compare the results given by various computational
protocols, including basis sets, density-functionals (including gradient
corrected local functionals, hybrids, double hybrids and range-separated
functionals), and various variants of time-dependent density-functional theory,
including the simplified Tamm-Dancoff approximation. An excellent choice for
these calculations is the range-separated functional CAM-B3LYP in combination
with the simplified Tamm-Dancoff approximation and a basis set of double-ζ
quality def2-SVP (mean absolute error [MAE] of ~0.05 eV). This is not surpassed
by more expensive approaches, not even by double hybrid functionals, and solely
systematic excitation energy scaling slightly improves the results (MAE ~0.04
eV). </p>
The time-dependent behavior of rock mass, which is generally governed by joints and shearing zones, is of great significance for engineering design and prediction of long-term deformation and stability. In situ creep test is a more effective method than laboratory test in characterizing the creep behavior of rock mass with joint or shearing zone due to the complexity of field conditions. A series of in situ creep tests on granite with joint at the shiplock area of the Three-Gorges Project and basalt with shearing zone at the right abutment of the Xiluodu Project were performed in this study. Based on the test results, the stress-displacement-time responses of the joints and basalt are analyzed, and their time-dependent constitutive model and model coefficients are given, which is crucial for the design to prevent the creep deformations of rock masses from causing the failure of the operation of the shiplock gate at the Three-Gorges Project and long-term stability of the Xiluodu arc dam.
Integrin α1β1 is one of the main collagen receptors in many cell types. A fast large-scale production, purification and crystallization method for the integrin α1 I domain is reported here. The α1 I domain was crystallized using the vapour-diffusion method with a reservoir solution containing a mixture of PEG 4000, sodium acetate, glycerol and Tris–HCl buffer. The crystals beong to the C2 space group, with unit-cell parameters a = 74.5, b = 81.9, c = 37.3 Å, α = γ = 90.0, β = 90.8°. The crystals diffract to 2.0 Å and a 94.2% complete data set to 2.2 Å has been collected from a single crystal with an R
merge of 5.8%.
Order-Nelectron transport calculations from ballistic to diffusive regimes by a time-dependent wave-packet diffusion method: Application to transport properties of carbon nanotubes