We present the calibration strategy for the 20 kton liquid scintillator central detector of the Jiangmen Underground Neutrino Observatory (JUNO). By utilizing a comprehensive multiple-source and multiple-positional calibration program, in combination with a novel dual calorimetry technique exploiting two independent photosensors and readout systems, we demonstrate that the JUNO central detector can achieve a better than 1% energy linearity and a 3% effective energy resolution, required by the neutrino mass ordering determination.

The Jiangmen Underground Neutrino Observatory (JUNO) features a 20 kt multi-purpose underground liquid scintillator sphere as its main detector. Some of JUNO's features make it an excellent location for B solar neutrino measurements, such as its low-energy threshold, high energy resolution compared with water Cherenkov detectors, and much larger target mass compared with previous liquid scintillator detectors. In this paper, we present a comprehensive assessment of JUNO's potential for detecting B solar neutrinos via the neutrino-electron elastic scattering process. A reduced 2 MeV threshold for the recoil electron energy is found to be achievable, assuming that the intrinsic radioactive background U and Th in the liquid scintillator can be controlled to 10 g/g. With ten years of data acquisition, approximately 60,000 signal and 30,000 background events are expected. This large sample will enable an examination of the distortion of the recoil electron spectrum that is dominated by the neutrino flavor transformation in the dense solar matter, which will shed new light on the inconsistency between the measured electron spectra and the predictions of the standard three-flavor neutrino oscillation framework. If eV , JUNO can provide evidence of neutrino oscillation in the Earth at approximately the 3 (2 ) level by measuring the non-zero signal rate variation with respect to the solar zenith angle. Moreover, JUNO can simultaneously measure using B solar neutrinos to a precision of 20% or better, depending on the central value, and to sub-percent precision using reactor antineutrinos. A comparison of these two measurements from the same detector will help understand the current mild inconsistency between the value of reported by solar neutrino experiments and the KamLAND experiment.

A novel 0D organic-inorganic metal halide hybrid (C13H16N2O2)2InCl6·Cl (1) has been obtained by integrating the mono-viologen derivative with InCl3. The compound 1 exhibits reversible and ultrafast UV/sunlight/X-ray induced photochromic properties,...

IrM (M = Fe, Co, and Ni) alloy nanoparticles (NPs) were synthesized in a solution by employing butyllithium as a reduction agent and oleylamine as a stabilizing agent, and the alumina-supported IrM bimetallic nanoparticles were tested for selective hydrogenation of various substituted nitroaromatics. The relevant characterizations including X-ray diffraction, X-ray photoelectron spectra, transmission electron microscopy, and diffuse reflectance fourier transform infrared with CO probes confirm that IrM NPs are uniform alloys. The obtained IrM/Al 2 O 3 catalysts show significantly enhanced catalytic activity as well as selectivity relative to individual monometallic Ir catalysts, indicating a unique catalytic property of bimetallic alloy nanostructures. Among these bimetallic catalysts, IrNi/Al 2 O 3 illustrate the highest activity and selectivity for hydrogenation of various substituted nitroaromatics. Calculations by density functional theory suggest that bimetallic structures of IrNi facilitate the reactant adsorption and product desorption, resulting in enhanced catalytic performance.

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We report af acile and generic method for the synthesis of hollowmesoporous silica nanoreactors (HMSNs) with small-sized metal oxide nanoparticles (NPs) inside their cavities.T hey were made by deposition of silica onto metalcontaining charge-driven polymer micelles and subsequent calcination. The micelles consist of 1) negatively charged supramolecular polyelectrolyte chains of bis-ligand-bound metal ions,a nd 2) water-soluble,n eutral/positive diblock copolymers.O wing to the facile coordination between transition-metal ion and the employed bidentate ligand, aseries of HMSNs with < 2nmM x O y NPs inside cavities (M = Mn, Co, Ni, Cu, or Zn) were obtained by simply varying the metal ions inside the micelles.The developed method circumvents the preand post-synthesis of metal oxide NPs;a fter calcination, hollowm esoporous nanostructures containing small-sized metal oxide NPs inside their cavities are directly obtained.

Recent progress has put the spotlight on functional nanoparticles encapsulated inside hollow silica nanospheres as socalled catalytic nanoreactors for various reactions. However, the synthetic methods used so far vary from one nanoparticle system to another, not providing access to the synthesis of a large variety of such materials. Here, we report an alternative, namely, a coordination-enhanced synthesis leading to a single system, which can directly produce a vast number of different hollow mesoporous silica nanoreactors with metal or metal-oxide nanoparticles inside their cavities (M@HMSNs or M x O y @HMSNs, where M stands for the chosen metal). We have successfully used the method with more than 21 different metals (Ru,

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