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Structural variants of high‐nuclearity clusters are extremely important for their modular assembly study and functional expansion, yet the synthesis of such giant structural variants remains a great challenge. Herein, we prepared a lantern‐type giant polymolybdate cluster (L‐Mo132) containing equal metal nuclearity with the famous Keplerate type Mo132 (K‐Mo132). The skeleton of L‐Mo132 features a rare truncated rhombic triacontrahedron, which is totally different with the truncated icosahedral K‐Mo132. To the best of our knowledge, this is the first time to observe such structural variants in high‐nuclearity cluster built up of more than 100 metal atoms. Scanning transmission electron microscopy reveals that L‐Mo132 has good stability. More importantly, because the pentagonal [Mo6O27]n− building blocks in L‐Mo132 are concave instead of convex in the outer face, it contains multiple terminal coordinated water molecules on its outer surface, which make it expose more active metal sites to display superior phenol oxidation performance, which is more higher than that of K‐Mo132 coordinated in M=O bonds on the outer surface. [ABSTRACT FROM AUTHOR]

In this paper, we mainly focus on 22 old white dwarfs and present two new magnetic monopoles (MMs) energy cooling resources models (I) and (II) based on MMs catalytic nuclear decay. We discussed their luminosity, and compared with the observations. The luminosities for these old White Dwarf stars (WDs) for models (I) and (II) are well in agreement with the observations L rad and the differences are no more than one order magnitude at relativistic low temperature (e.g. T 6 = 0. 0 1). However, at relativistic high temperature (e.g. T 6 = 1 0), the observations L rad can be four and two orders of magnitude lower than those of models (I) and (II), respectively. We also compared the results of models (I) and (II) by scaling factor k 3 . One can see that the maximum of the luminosities for model (I) are 185.2705 and 512.7054 times larger than those of model (II) for old WD 1 2 4 7 + 5 5 1 a at T 6 = 0. 0 1 , 10, respectively. On the other hand, the minimum of the luminosities for model (I) are 7.3563 and 34.8064 times larger than those of model (II) for old WD 1444-175 at T 6 = 0. 0 1 , 10, respectively. By considering the effect on the mass radius relationship by the number of the MMs captured in WDs and catalytic nuclear decay, our results show that the study of model (II) may be an improving estimation, and the monopole-catalyzed nucleon decay process could be preventing white dwarfs from cooling down into a stellar graveyard by keeping them hot. [ABSTRACT FROM AUTHOR]

We propose a question that why no late type M and much later type N white dwarfs (WDs) with surface temperatures less than 3000 K have ever been observed? On the basis of proton decay catalyzed by magnetic monopoles(MMs), we have presented four new energy-source models associated with MMs to discuss the cooling of WDs by some observations from seven red giant stars with LAMOST. It is found that the number of MMs captured by a WD can reach the maximum value of 9. 5 8 1 6 × 1 0 1 7 when the MMs flux ϕ = 9. 5 9 × 1 0 − 2 6 cm − 2 s − 1 sr − 1 . The good agreement of our luminosities calculated for WDs with the observations shows that our models are rational due to the Rubakov Callan (RC) effect by MMs. It is concluded that the energy source of WDs is the proton decay catalyzed by MMs. We obtain a new limit of the MMs flux of ϕ 〈 σ m v T 〉 − 2 8 ≤ 4. 2 2 4 2 × 1 0 − 1 3 cm − 2 s − 1 sr − 1 for WDs when the number density of nucleons n B c = 7. 9 9 × 1 0 3 3 cm − 3 and asteroseismic correction factor f △ ν = 1. 0 0 due to the RC effect by MMs. [ABSTRACT FROM AUTHOR]