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For those colloidal semiconductor CdSe nanospecies that exhibit sharp optical absorption doublets, different explanations have appeared in the literature regarding their morphological nature and formation, with no consensus reached. Here, we discuss the transformation pathway in two types of CdSe nanoplatelets (NPLs), from NPL-393 to NPL-460, exhibiting absorption doublets at 373/393 and 433/460 nm, respectively. Synchrotron-based small/wide-angle X-ray scattering (SAXS/WAXS) was performed to monitor the

Divergent interpretations have appeared in the literature regarding the structural nature and evolutionary behavior for photoluminescent CdSe nanospecies with sharp doublets in optical absorption. We report a comprehensive description of the transformation pathway from one CdSe nanospecies displaying an absorption doublet at 373/393 nm to another species with a doublet at 433/460 nm. These two nanospecies are zero-dimensional (0D) magic-size clusters (MSCs) with 3D quantum confinement, and are labeled dMSC-393 and dMSC-460, respectively. Synchrotron-based small-angle X-ray scattering (SAXS) returns a radius of gyration of 0.92 nm for dMSC-393 and 1.14 nm for dMSC-460, and indicates that both types are disc shaped with the exponent of the SAXS form factor equal to 2.1. The MSCs develop from their unique counterpart precursor compounds (PCs), which are labeled PC-393 and PC-460, respectively. For the dMSC-393 to dMSC-460 transformation, the proposed PC-enabled pathway is comprised of three key steps, dMSC-393 to PC-393 (Step 1), PC-393 to PC-460 (Step 2 involving monomer addition), and PC-460 to dMSC-460 (Step 3). The present study provides a framework for understanding the PC-based evolution of MSCs and how PCs enable transformations between MSCs.

Colloidal semiconductor ternary CdTeS magic-size clusters (MSCs) have not been reported. Here, we present the first synthesis of CdTeS MSCs at room temperature and our understanding of the evolution pathway. The MSCs exhibit sharp optical absorption peaking at 381 nm and are labeled MSC-381. CdTeS MSC-381 evolves when pre-nucleation-stage samples of binary CdTe and CdS that do not contain quantum dots (QDs) are separately prepared and then mixed and incubated at room temperature. We propose that CdTeS MSC-381 evolves from its precursor compound (PC) via quasi-isomerization. Synchrotron-based small-angle X-ray scattering suggests that PCs/MSCs of CdTe and CdTeS are similar in sizes. We propose further that the CdTeS PC forms from the substitution reaction between the CdTe PC and the CdS monomer/fragment (Mo/Fr). The present study paves the way to the room-temperature evolution of ternary MSCs and provides an in-depth understanding of the PC to MSC transformation.

The whole evolution processes, from precursors to quantum dots (QDs), were in situ investigated by SAXS and UV-vis. Diphenylphosphine (HPPh2) accelerates the dissolution of zinc oleate lamellar mesophase in the presence of selenide tri-n-octylphosphine (SeTOP) at a low temperature of 40 °C via the equilibrium of SeTOP + HPPh2 ⇔ SePPh2H + TOP.

BACKGROUND The purpose of this study was to investigate the clinical value of procalcitonin (PCT) and C-reactive protein (CRP) in the differential diagnosis of neonatal jaundice. METHODS Eighty-five cases of neonatal jaundice in our hospital from January 2016 to March 2019 were selected as research subjects, including 30 cases of physiological jaundice, 23 cases of infectious jaundice, and 32 cases of he-molytic jaundice. Five milliliters of non-anticoagulated venous peripheral blood and 3 mL EDTA-K+ anticoagulated venous peripheral blood were sampled from each newborn when the symptoms of jaundice occurred. The non-anticoagulated blood samples were then centrifuged at 3,500 rpm for 7 minutes and the serum was used for PCT and bilirubin examinations, and the anticoagulated blood samples were prepared for CRP examination. Receiver operating characteristic (ROC) curve analysis was performed for the evaluation of differential diagnosis of neonatal jaundice by PCT, CRP, and bilirubin levels. RESULTS Analyses of variance showed the postnatal age of jaundice occurring in the physiological jaundice group was older than those in the infectious jaundice and hemolytic jaundice groups (p < 0.001), and the PCT and CRP levels in the infectious jaundice group were higher than those in the hemolytic jaundice and physiological jaundice groups (p < 0.001). Pearson's correlation analysis indicated that the levels of PCT and CRP were negatively correlated with postnatal age in the physiological jaundice group (p < 0.05). ROC curve analysis demonstrated that PCT and CRP had the highest differential diagnosis efficacy of neonatal pathological and neonatal physiological jaundice with PCT and CRP at 0.70 µg/L and 8.50 mg/L, respectively, as well as the highest differential diagnosis efficacy of neonatal infectious jaundice and neonatal hemolytic jaundice with PCT and CRP at 1.84 µg/L and 13.50 mg/L, respectively. CONCLUSIONS This study suggested that PCT and CRP possessed important clinical values in the differential diagnosis of neonatal jaundice, and PCT was superior to the differential diagnosis of neonatal infectious jaundice.