Intra-Configurational Spin-Flip d d Transition of Mo (III) Doped Perovskite for Ultra-Narrow Near Infrared-II Emission in Ambient Conditions.

Sharp near‐infrared‐II (NIR‐II) emissions are typically achieved through electronic transitions of rare‐earth ions, while transitions in transition metal ions are broad due to electron–ligand interactions. An exception is the intra‐configurational spin‐flip (ICSF) transition like t 2g 3 t 2g 3 of Mo 3+ emitting sharp NIR‐II emission, but only at cryogenic temperatures under vacuum. The high oxophilicity of Mo 3+ created defects during the synthesis, quenching the emission at room temperature. Herein, we overcome this issue by synthesizing Mo 3+ − doped Cs 2 NaInCl 6 double perovskites in a reducing H 3 PO 2 environment. [MoCl 6 ] 3− octahedra are formed, exhibiting ultra‐narrow ICSF ( 2 T 1g / 2 E g 4 A 2g ) NIR‐II emission at 1095 nm in ambient conditions. In addition, a second ICSF 2 T 2g 4 A 2g emission is observed at 700 nm, violating the Kasha's rule. The intensity of ICSF emissions increase with increasing temperature (7–350 K) due to vibronic coupling relaxing the Laporte selection rule. The samples are stable for more than 6 months in ambient conditions, allowing for a detailed study of fundamental photophysics and fabrications of phosphor‐converted light emitting diodes. This is the first Mo 3+ –based NIR‐II optoelectronic device, opening opportunities for applications like optical fibers and lasing.

While acute stressors can be detrimental, environmental stress conditioning can improve performance. To test the hypothesis that physiological status is altered by stress conditioning, we subjected juvenile Pacific geoduck, Panopea generosa, to repeated exposures of elevated pCO2 in a commercial hatchery setting followed by a period in ambient common garden. Respiration rate and shell length were measured for juvenile geoduck periodically throughout short-term repeated reciprocal exposure periods in ambient (~550 μatm) or elevated (~2400 μatm) pCO2 treatments and in common, ambient conditions, 5 months after exposure. Short-term exposure periods comprised an initial 10-day exposure followed by 14 days in ambient before a secondary 6-day reciprocal exposure. The initial exposure to elevated pCO2 significantly reduced respiration rate by 25% relative to ambient conditions, but no effect on shell growth was detected. Following 14 days in common garden, ambient conditions, reciprocal exposure to elevated or ambient pCO2 did not alter juvenile respiration rates, indicating ability for metabolic recovery under subsequent conditions. Shell growth was negatively affected during the reciprocal treatment in both exposure histories; however, clams exposed to the initial elevated pCO2 showed compensatory growth with 5.8% greater shell length (on average between the two secondary exposures) after 5 months in ambient conditions. Additionally, clams exposed to the secondary elevated pCO2 showed 52.4% increase in respiration rate after 5 months in ambient conditions. Early exposure to low pH appears to trigger carryover effects suggesting bioenergetic re-allocation facilitates growth compensation. Life stage-specific exposures to stress can determine when it may be especially detrimental, or advantageous, to apply stress conditioning for commercial production of this long-lived burrowing clam.

Fruits of mandarin, orange, grapefruit and lemon, which received no fungicide treatment before harvest and at packing, stored at ambient temperature for 2 months, and kept at cold storage conditions for two and four months. During storage 16.8, 25.1 and 65.4 % crop losses were observed, respectively, due to development of total postharvest diseases. Citrus trees were sprayed with benomyl, fosetyl-Al, and CuSO4.5H2O+ZnSO4.6H2O+hydrated lime to control postharvest diseases 1-1.5 month before harvest time. Also, dipping of fosetyl-Al, benomyl, sodium o-phenylphenate, 2.4-D isopropyl-ester in water, and spraying of benomyl and imazalil in a water-wax were used to control for postharvest diseases of citrus fruits during packing processes. Some lemon fruits were stored in wrapped biphenyl emitted papers. Combination of preharvest fungicide treatments with treatments during packing, assumed to be the most effective control measure against postharvest diseases, resulted 2.4 % crop losses in 2 months ambient conditions, and 9.8-20.9 % in 2-4 months cold storage conditions. When compared with non treated control groups, the savings were 14.4 % in 2 months ambient conditions, and 15.3-44.5 % in 2-4 months cold storage conditions. The effect of combined treatments (some fungicide treatments in 1-1.5 month before harvest, and during packing period) on control of postharvest diseases was 89.9 aünd 60.1-72.1 % in ambient and cold storage conditions, respectively. Mandarin, orange, grapefruit and lemon fruits which were only treated during 1-1.5 month before the harvest were stored for 2 months in ambient conditions and for 4 months in cold storage rooms. In this case, total postharvest diseases were controlled at a rate of 57.5 and 40.0 %, respectively. However, in the case of fruits treated with fungicides alone in packinghouse, showed controlling levels of 68.8 and 55.1 %. The incidence of total postharvest diseases in the lemon fruits which were treated with the combined fungicide treatments and wrapped into biphenyl emitted papers stored 2 months in ambient and 2-4 months cold storage conditions were 2.5 and 0, 7.5 % and resulting disease control were 18.8 and 15.0, 33.8 %, respectively. In this study, then main postharvest diseases observed were Alternaria citri Ellis et Pierce stem end rot, Penicillium italicum Wehmer and Penicillium digitatum Sacc. blue and green molds, Colletotrichum gloeosporioides ( Penz.) Sacc. antrachnose, and Geotrichum candidum Link. ex Pers. sour rot on rotted mandarin, orange, grapefruit, and lemon fruits which were treated with the combined fungicide treatments. In combined fungicide treatments, A. citri

A series of Ru/zeolites with Ru content in the range of 1–7 wt.% was prepared by cationic exchange in an aqueous Ru(NH3)6Cl3 solution, at room temperature, of two H–BEA (different particle sizes but same Si/Al ratio of 13), a Cs–BEA (Si/Al = 13) and a NaY (Si/Al = 2.4), zeolitic supports. The quantitative UV-Visible analysis of the solutions during exchange showed that about 90% of the exchange process was over within the first hour of contact between the zeolite and the solution. This analysis also provided an accurate measurement of Ru content in the solids in real time and gave access to the Ru exchange capacities of the zeolitic supports. Diffuse reflectance UV-Visible spectroscopy showed that the [Ru(NH3)6]3+ cations were exchanged as such in all the BEA zeolites and were not modified after storage of the solids for several months in ambient conditions. On the contrary, the Ru hexaammine cations in NaY were gradually transformed into the Ru-red-wine [(NH3)5RuIIIO–RuIV(NH3)4–O–RuIII(NH3)5]6+ and Ru-brown [(NH3)5RuIV–O–RuIII(NH3)4–O–RuIV(NH3)5]7+ cationic trimers, in agreement with literature data. The transformation rate increased with the Ru loading. The reasons for the higher stability of the [Ru(NH3)6]3+ cations in the BEA series than in NaY are discussed.

Focus on vacuum and cryogenics

In recent years, a range of two-dimensional boron polymorphs, collectively referred to as borophene, have been experimentally realized on a diverse set of metallic substrates by bottom-up synthesis in ultrahigh vacuum (UHV). However, since borophene is highly reactive chemically and rapidly oxidizes in ambient conditions, robust encapsulation methods are needed to ensure the long-term stability of borophene outside of UHV environments. Here, we demonstrate that encapsulation using UHV electron-beam evaporation of alumina (AlOx) prevents oxidation of borophene in ambient conditions. This protection of borophene from chemical degradation is achieved with UHV-deposited AlOx encapsulated layers as thin as 3.7 nm. X-ray photoelectron spectroscopy and scanning probe microscopy confirm that this encapsulation scheme preserves the integrity of borophene for at least 12 months in ambient conditions. This long-term stability addresses a critical hurdle in the processing and integration of borophene into practical device architectures.

Employing N-phenyl-tribenzo[b,d,f]azepine as a new electron-donating group to construct high-emissive AIE molecules for NIR-II fluorescence imaging.

Laser materials based on transition metal ions

The flour from the presscake in the production of Cucurbita pepo var. styriaca seed virgin oil has features that make it interesting for use in baked goods and pasta production because of its characteristic green color, intense flavor and nutritional benefits. To determine the nutritional composition of this new product, elaborations of flour were made with seeds from Uruguay and Europe. They were analyzed for moisture, fat content, protein, ash, fiber, sodium, vitamin B1, vitamin E, fatty acid profile, sterols, amino acids and total carbohydrates. Physicochemical and microbiological stability have been studied for 12 months at ambient conditions with the flour packaged with a polyethylene, polyester and aluminum tri-laminate. The flour is characterized as a vegetable protein product (48,3 %) and as an important source of fiber (11 %). It has 21,7 % of lipids of which 38 % are MUFA and 53,4 % are PUFA, highlighting the oleic and linoleic acid contents what makes it desirable from nutritional and culinary standpoints. It features 3,7 mg of vitamin E per 100 g and 2967 mg / kg of sterols. In flour from the presscake in the production of pumpkin seed virgin oil acidity and moisture remains stable, while the fungi and yeasts number decrease during 12 months in ambient conditions used in this study, with trilaminate polyethylene aluminized polyester.

Environmentally durable superhydrophobic surfaces with robust photocatalytic self-cleaning and self-healing properties prepared via versatile film deposition methods

Three rigid and structurally simple heterocyclic stilbene derivatives, (E)‐3H,3′H‐[1,1′‐biisobenzofuranylidene]‐3,3′‐dione, (E)‐3‐(3‐oxobenzo[c] thiophen‐1(3H)‐ylidene)isobenzofuran‐1(3H)‐one, and (E)‐3H,3′H‐[1,1′‐bibenzo[c] thiophenylidene]‐3,3′‐dione, are found to fluoresce in their neat solid phases, from upper (S2) and lowest (S1) singlet excited states, even at room temperature in air. Photophysical studies, single‐crystal structures, and theoretical calculations indicate that large energy gaps between S2 and S1 states (T2 and T1 states) as well as an abundance of intra and intermolecular hydrogen bonds suppress internal conversions of the upper excited states in the solids and make possible the fluorescence from S2 excited states (phosphorescence from T2 excited states). These results, including unprecedented fluorescence quantum yields (2.3–9.6 %) from the S2 states in the neat solids, establish a unique molecular skeleton for achieving multi‐colored emissions from upper excited states by “suppressing” Kasha's rule.

Highly luminescent CsPbX3@MIL-53(Al) nanoarchitectonics with anomalous stability towards flexible emitting films

PurposeThe aerospace, energy and automotive industries have seen wide use of composite materials because of their excellent mechanical properties, along with the benefit of weight reduction savings. As such, the purpose of this study is to provide an understanding of the mechanical performance of these materials under extreme operational conditions characteristic of in-service environments.Design/methodology/approachThis study is novel in that it has evaluated the tensile performance and fracture response of additively manufactured continuous carbon fiber embedded in an onyx matrix (i.e. nylon with chopped carbon fiber) at cryogenic and room temperatures, for specimens manufactured with an angle between the specimen lying plane and the working build plane of 0°, 45° and 90°.FindingsResearch findings reveal enhanced tensile properties (i.e. ultimate tensile strength and modulus of elasticity) by the 0° (X) built specimens, as compared with the 45° (XZ45) and 90° (Z) built specimens at cryogenic temperature. A reduction in ductility is observed at cryogenic temperature for all build orientations. Fractographic analysis reveals the presence of fiber pullout/elongation, pores within the onyx matrix and chopped carbon fiber near fracture zone of the onyx matrix.Research limitations/implicationsResearch findings present tensile properties (i.e. ultimate tensile strength, modulus of elasticity and elongation%) for three-dimensional (3D)-printed onyx with and without reinforcing continuous carbon fiber composites at cryogenic and room temperatures. Reinforcement of continuous carbon fibers and reduction to cryogenic temperatures appears to result, in general, in an increase in the tensile strength and modulus of elasticity, with a reduction in elongation% as compared with the onyx matrix tensile performance reported at room temperature. Fracture analysis reveals continuous carbon fiber pull out for onyx–carbon fiber samples tested at room temperature and cryogenic temperatures, suggesting weak onyx matrix–continuous carbon fiber adhesion.Originality/valueTo the best of the authors’ knowledge, this study is the first study to report on the cryogenic tensile properties and fracture response exhibited by 3D-printed onyx–continuous carbon fiber composites. Evaluating the viability of common commercial 3D printing techniques in producing composite parts to withstand cryogenic temperatures is of critical import, for aerospace applications.

Enhancing NIR-II luminescence of erbium sublattice through lanthanide-mediated energy modulation

Size-controlled gold (Au) nanoparticles (NPs) were synthesized for the first time in large quantities in the presence of poly(N-vinyl-2-pyrrolidone) (PVP) under microwave heating for just 60 s in aqueous solutions. Results showed that the Au NPs were small in size, which could be successfully controlled through varying the PVP to Au(III) molar ratio and by using different molecular weight PVP molecules. The particles were stable for more than three months in ambient conditions. The synthesized PVP−Au NPs exhibited excellent catalytic activity for the reduction of aromatic nitro compounds by NaBH4 in water. The Au NPs helped in the electron transfer process between the BH4− and nitro compounds, which were successfully reduced to their amino derivatives. The present method is beneficial for fast synthesis of Au NPs as well as reduction of different aromatic nitro compounds.