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Rare-earth doped β-NaYbF4 upconversion phosphors were synthesized using a simple hydrothermal procedure. It is found that under 980 nm excitation β-NaYbF4:0.1%Tm are more efficient than β-NaYF4:20%Yb,0.1% that is known as one of the most effective upconversion materials. The unusual result may be related to the particles size. After introducing 0.1%Er3+ into the NaYbF4:0.1%Tm lattice, the upconversion white emission with color coordinate of (0.3016,0.3748) is obtained. The investigation of achieving mechanism indicates that besides the energy transfer from Yb3+ to Tm3+ and Er3+, respectively, there exists a new energy transfer process: 3F2,3 (Tm3+) + 4I11/2 (Er3+) → 3F4 (Tm3+) + 2H11/2/4S3/2 (Er3+).

Delivery of proteins and organelles to the vacuole by autophagy and the cytoplasm to vacuole targeting (Cvt) pathway involves novel rearrangements of membrane resulting in the formation of vesicles that fuse with the vacuole. The mechanism of vesicle formation and the origin of the membrane are complex issues still to be resolved. Atg18 and Atg21 are proteins essential to vesicle formation and together with Ygr223c form a novel family of phosphoinositide binding proteins that are associated with the vacuole and perivacuolar structures. Their localization requires the activity of Vps34, suggesting that phosphatidylinositol(3)phosphate may be essential for their function. The activity of Atg18 is vital for all forms of autophagy, whereas Atg21 is required for the Cvt pathway but not for nitrogen starvation-induced autophagy. The loss of Atg21 results in the absence of Atg8 from the pre-autophagosomal structure (PAS), which may be ascribed to a reduced rate of conjugation of Atg8 to phosphatidylethanolamine. A similar defect in localization of a second ubiquitin-like conjugate, Atg12-Atg5, suggests that Atg21 may be involved in the recruitment of membrane to the PAS.

Reaction mechanisms between MH (M=B, Al) and the H2S molecule have been theoretically studied. The G3 ab initio and DFT calculations demonstrate that only one stable addition complex (HM:SH2, M=B, Al) can be formed, and that, starting from the addition complex (HM:SH2) two parallel reaction channels have been found: one is an addition reaction to give H2MSH via the three-membered ring transition state (TS), and the other is a dehydrogenation reaction to give MSH+H2 via the four-membered ring TS. Thermodynamics and Eyring transition state theory (TST) with the Wigner correction are also used to compute the thermodynamic functions, the equilibrium constants, A factors, and the rate constants of these reaction channels at 300–1500 K. The calculated results predict that the product H2BSH in the system of BH+H2S and the product AlSH+H2 in the system of AlH+H2S will be mainly observed. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001

An ab initio study on the title compound was performed in this work. The structures at MP2(FULL)/6-311G* level of theory and their energies at the CCSD(T)/6-311G* level of theory were provided. Their vibrational frequencies and ²⁹Si nuclear magnetic resonance (NMR) chemical shift had been carried out too. The thermodynamic data were calculated in order to help judge the relative stability of the isomers of SiCl3Li at experimental temperatures. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 79: 17–24, 2000

This article presents the intrapair and interpair electron correlation energies of LiF2. The total interpair correlation energy predominates. Hence, in building models for correcting post-Hartree–Fock calculations to obtain accurate electron correlation energies, the interpair electron correlation energy must be considered. Based on this result and our previous results, a fundamental assumption underlying the so-called higher-level correction in the Pople G1 the G2 theory is flawed. © 1997 John Wiley & Sons, Inc. Int J Quant Chem 64: 171–174, 1997