Harveyfabricius0513

To demonstrate the potential of this method, called tensor product selected configuration interaction (TPSCI), we present numerical results for a diverse set of examples (1) modified Hubbard model with different inter- and intracluster hopping terms, (2) less obviously clusterable cases of bond breaking in N2 and F2, and (3) ground state energies of large planar π-conjugated systems with active spaces of up to 42 electrons in 42 orbitals. These numerical results show that TPSCI can be used to significantly reduce the number of SCI variables in the variational space, thus paving a path for extending these deterministic and variational SCI approaches to a wider range of physical systems.The applications of a newly designed chiral naphthyl-C2-indole bifunctional phosphine organocatalyst in stereoselective formal [4 + 2] cycloaddition reactions were reported. The chiral naphthyl-C2-indole skeleton was introduced to bifunctional phosphine organocatalysis for the first time, and excellent stereocontrol was achieved in two types of formal [4 + 2] cycloaddition reactions. With the optimal catalyst, a series of chiral spirooxindole and hydrodibenzofuran architectures were produced in moderate to good yields with excellent stereoselectivities (up to >99% ee, >201 dr).The growing use of silver-based nanoparticles (Ag-b-NPs) in everyday products goes hand in hand with their release into the environment, resulting in ng L-1 traces in natural water bodies. In order to assess their fate, possible transformations and ecotoxicology-essential information to proper risk assessment-particle size, shape, and chemical composition have to be determined. Transmission electron microscopy coupled with energy dispersive X-ray spectroscopy (TEM-EDX) is a powerful tool for determining these particle characteristics, but it requires high particle concentrations in order to produce statistically reliable results. In this study, we will present the extraction of Ag-b-NPs at environmentally relevant concentrations down to 5 ng L-1 from artificial as well as environmental water samples via cloud point extraction on a repetitive basis. The combination with an on-grid centrifugation technique ensures an efficient concentration and deposition of the extracted particles onto the TEM grid for subsequent TEM-EDX measurements. Furthermore, electron microscopy investigations were supplemented by single particle inductively coupled plasma mass spectrometry (sp-ICP-MS) measurements. Ag-b-NPs were successfully visualized and characterized at environmentally relevant concentrations of 5 ng L-1 with TEM-EDX and sp-ICP-MS measurements. Their size, shape, and chemical composition were not affected by the sample preparation.China's fertilization practices contribute greatly to the global biogeochemical nitrogen (N) and phosphorus (P) flows, which have exceeded the safe-operating space. Here, we quantified the potentials of improved nutrient management in the food chain and spatial planning of livestock farms on nutrient use efficiency and losses in China, using a nutrient flow model and detailed information on >2300 counties. NVP-LAQ824 Annual fertilizer use could be reduced by 26 Tg N and 6.4 Tg P following improved nutrient management. This reduction N and P fertilizer use would contribute 30% and 80% of the required global reduction, needed to keep the biogeochemical N and P flows within the planetary boundary. However, there are various barriers to make this happen. A major barrier is the transportation cost due to the uneven distributions of crop land, livestock, and people within the country. The amounts of N and P in wastes and residues are larger than the N and P demand of the crops grown in 30% and 50% of the counties, respectively. We argue that a drastic increase in the recycling and utilization of N and P from wastes and residues can only happen following relocation of livestock farms to areas with sufficient cropland.The ambient temperature photoinduced polymerization of compressed (P less then 1 GPa) fluid ethylene was characterized by transient infrared absorption spectroscopy with a resolution of few nanoseconds, 3 orders of magnitude higher than previously reported. The reaction has been studied under both one- and two-photon excitation evidencing in the latter case its occurrence only in the presence of different transition metal oxides. Their photocatalytic activity is ascribed to the stabilization of the excited biradicals through electron density exchange between the d orbitals of the metal and the π antibonding orbitals of ethylene which lengthens the lifetime of the biradicals. In both one- and two-photon activation cases the polymerization is characterized by an initial step distinguished by a molecularity of 0.15 ± 0.02 identified as the activation step of the reaction lasting, in the one-photon excitation case, a few hundreds of nanoseconds. Using pulsed excitation the reaction evolves toward a free radical polymerization only under one-photon excitation whereas the critical concentration of radicals required to propagate the reaction is never achieved in the two-photon excitation case. Comparison with continuous wave excitation unambiguously identifies in the average power released to the sample the key factor to drive quantitatively and qualitatively the polymerization.In the presence of a catalytic amount of Pd(OAc)2 and XantPhos, the three-component reaction of ynones, imines, and aryl iodides affords fully substituted alkylidene-furan-3(2H)-ones via a sequence of the Mannich reaction followed by chemo- and regioselective oxypalladation and reductive elimination. One carbon-oxygen and two carbon-carbon bonds are generated to afford the heterocycle in good to excellent yield.The surface of proteins is vital in determining protein functions. Herein, a program, Protein Surface Printer (PSP), is built that performs multiple functions in quantifying protein surface domains. Two proteins, PETase and cytochrome P450, are used to validate that the program supports atomistic simulations with different combinations of programs and force fields. A case study is conducted on the structural analysis of the spike proteins of SARS-CoV-2 and SARS-CoV and the human cell receptor ACE2. Although the surface domains of both spike proteins are highly similar, their receptor-binding domains (RBDs) and the O-linked glycan domains are structurally different. The O-linked glycan domain of SARS-CoV-2 is highly positively charged, which may promote binding to negatively charged human cells.