Infrared spectra of mass-selected clusters NOf(H20), for n = 1 to 5 were recorded from 2700 to 3800 cm-' by vibrational predissociation spectroscopy. Vibrational frequencies and intensities were also calculated for n= 1 and 2 at the second-order MQller-Plesset (MP2) level, to aid in the interpretation of the spectra, and at the singles and doubles coupled cluster (CCSD) level energies of it = 1 isomers were computed at the MP2 geometries. The smaller clusters (n = 1 to 3) were complexes of HZ0 ligands bound to a nitrosonium ion NO+ core. They possessed perturbed HZ0 stretch bands and dissociated by loss of H,O. The Ha0 antisymmetric stretch was absent in y1= 1 and gradually increased in intensity with n. In the n =4 clusters, we found evidence for the beginning of a second solvation shell as well as the onset of an intracluster reaction that formed HONO. These clusters exhibited additional weak, broad bands between 3200 and 3400 cm-' and two new minor photodissociation channels, loss of HONO and loss of two HZ0 molecules. The reaction appeared to go to completion within the n =5 clusters. The primary dissociation channel was loss of HONO, and seven vibrational bands were observed. From an analysis of the spectrum, we concluded that the n=5 cluster rearranged to form H30'(H20)s(HONO), i.e., an adduct of the reaction products.

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Purpose To compare measurements of murine ocular axial lengths (AL) made with 780 nm partial coherence interferometry (PCI) and 1310 nm spectral domain–optical coherence tomography (SD-OCT). Methods AL was measured at postnatal day (P) 58 in C57BL/6J mice. Repeated AL measurements were taken using a custom-made 780 nm PCI and a commercial 1310 nm SD-OCT. Intra- and inter-user variability was assessed along the central optical axis as well as two-degree off-axes angles with the SD-OCT. Data were collected and analyzed using Cronbach’s alpha (α), Bland-Altman coefficient of repeatability (CR), agreement plots, and intra-class correlation coefficients (ICC). Results Axial length measurements agreed well between the two instruments (3.262 ± 0.042 mm for PCI; 3.264 ± 0.047 mm for SD-OCT; n= 20 eyes). The ICC for PCI compared to SD-OCT was 0.92, confirming high agreement between the two instruments. Intra-user ICC for the PCI and SD-OCT were 0.814 and 0.995, respectively. Similarly, inter-user ICC for PCI and SD-OCT were 0.970 and 0.943, respectively. Using SD-OCT, a two-degree misalignment of the eye along the horizontal meridian produced mean differences in AL of −0.002 ± 0.017 mm relative to the centrally aligned images, while similar misalignment along the vertical meridian created 0.005 ± 0.018 mm differences in AL measurements. Conclusions AL measurements from the 780 nm PCI and 1310 nm SD-OCT correlate well. Multiple statistical indices indicate that both instruments have good precision and agreement for measuring murine ocular axial length in vivo. While the vertical meridian had the greater variability in AL in the small mouse eye; two-degree off-axes differences were within the standard deviation of centrally aligned AL.

Infrared spectra of clusters of protonated nitric acid and water exhibit a marked change with cluster size, indicating that an intracluster reaction occurs with sufficient solvation. In small clusters, H 2 0 binds to a nitronium ion core, but at a critical cluster size the NO{ reacts. A lower bound of 174 kcal!mol is found for the proton affinity of HN0 3 •

Silanium ions are an important class of hypervalent molecules, and the determination of their structure will yield insights into the nature of nonclassical bonding and provide a contrast to the bonding in carbonium ions. We report the infrared spectrum of the mass-selected silicon hydride cluster ion 28SiH7, detected by vibrational predissociation spectroscopy. Silanium ions were foimed in a pulsed high pressure glow discharge and cooled by the subsequent supersonic expansion. Photodissociation spectra were obtained using a tandem time-of-flight mass spectrometer: SiH7 ions were mass-selected and excited by a tunable infrared laser. The resulting photofragments were detected using a reflectron as a mass analyzer. We observed a vibrational band at 3865 cm1, which was the only one observed from 3500 cm1 to 4200 cm1. This result suggests that the molecule might form a symmetric complex with the structure H2 SiH3H2, in contrast to the species CH7, which has the structure CH5H2.

Pathogenic bacteria can proliferate rapidly on porous fabrics to form bacterial plaques/biofilms, resulting in potential sources of cross-transmissions of diseases and increasing cross-infection in public environments. Many works on antibacterial modification of cotton fabrics have been reported, while very few works were reported to endow poly(ethylene terephthalate) (PET) fabrics with non-leaching antibacterial function without compromising their innate physicochemical properties though PET is the most widely used fabric. Therefore, it is urgent to impart the PET fabrics with non-leaching antibacterial activity. Herein, a novel N- halamine compound, 1-chloro-3-benzophenone-5,5-dimethylhydantoin (Cl-BPDMH), was developed to be covalently bonded onto PET fabrics, rendering non-leaching antibacterial activity while negligible cytotoxicity based on contact-killing principle. Bacterial was easily adhered to Cl-BPDMH finished PET fabrics, and then it was inactivated quickly within 10 s. Furthermore, the breaking strength, breaking elongation, tearing strength, water vapor permeability, air permeability and whiteness of Cl-BPDMH finished PET fabrics were improved obviously compared to raw PET fabrics. Hence, this work developed a facile approach to fabricate multifunctional synthetic textiles to render outstanding and rapid bactericidal activity without compromising their physicochemical properties and biocompatibility. Supplementary Information The online version contains supplementary material available at 10.1007/s42765-021-00100-z.

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The Closeby Habitable Exoplanet Survey (CHES) mission is proposed to discover habitable-zone Earth-like planets of the nearby solar-type stars ($\sim 10~\mathrm{pc}$ away from our solar system) via micro-arcsecond relative astrometry. The major scientific objectives of CHES are: to search for Earth Twins or terrestrial planets in habitable zones orbiting 100 FGK nearby stars; further to conduct a comprehensive survey and extensively characterize the nearby planetary systems. The primary payload is a high-quality, low-distortion, high-stability telescope. The optical subsystem is a coaxial three-mirror anastigmat (TMA) with a $1.2 \mathrm{~m}$-aperture, $0.44^{\circ} \times 0.44^{\circ}$ field of view and $500 \mathrm{~nm}-900 \mathrm{~nm}$ working waveband. The camera focal plane is composed of 81 MOSAIC scientific CMOS detectors each with $4 \mathrm{~K} \times 4 \mathrm{~K}$ pixels. The heterodyne laser interferometric calibration technology is employed to ensure micro-arcsecond level (1 $\mu$as) relative astrometry precision to meet the requirements for detection of Earth-like planets. CHES satellite operates at the Sun-Earth L2 point and observes the entire target stars for 5 years. CHES will offer the first direct measurements of true masses and inclinations of Earth Twins and super-Earths orbiting our neighbor stars based on micro-arcsecond astrometry from space. This will definitely enhance our understanding of the formation of diverse nearby planetary systems and the emergence of other worlds for solar-type stars, and finally to reflect the evolution of our own solar system.