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Simulations of photochemical reaction dynamics have been a challenge to the theoretical chemistry community for some time. In an effort to determine the predictive character of current approaches, we predict the results of an upcoming ultrafast diffraction experiment on the photodynamics of cyclobutanone after excitation to the lowest lying Rydberg state (S2). A picosecond of nonadiabatic dynamics is described with ab initio multiple spawning. We use both time dependent density functional theory (TDDFT) and equation-of-motion coupled cluster singles and doubles (EOM-CCSD) theory for the underlying electronic structure theory. We find that the lifetime of the S2 state is more than a picosecond (with both TDDFT and EOM-CCSD). The predicted ultrafast electron diffraction spectrum exhibits numerous structural features, but weak time dependence over the course of the simulations. [ABSTRACT FROM AUTHOR]

Objective： This study aimed to solve the problems of yellowing, discoloration and quality preservation of broccoli after harvesting. Methods： Broccoli was fumigated with chlorine dioxide gas at different mass concentrations (0,0.2, 0.5, 1.0, 1.5, 2.0 mg/L) at 23 ℃, and the sensory, color, yelination grade, physiological and biochemical indexes and related browning enzyme activities of broccoli were determined after 0,2,4,6,8 days of storage. Results： Compared with the control group, different mass concentrations of ClO2 could inhibit the mass loss rate, yellowing browning and spoilage of flower buds of broccoli. ClO2 at 0.5 and 1.0 mg/L had a more significant effect on the maintenance of chlorophyll content, color difference a* and b*, and the inhibition of PPO and POD enzyme activities in broccoli. Among them, 0.5 mg/L ClO2 had the best effect on maintaining the color difference value of broccoli flower buds, and the yelination grade was still grade Ⅱ on the 8th day of storage. Simultaneously, it effectively maintained the vitamin C content and delayed the yelination and Browning of flower buds. Conclusion： It is necessary to control the concentration of ClO2 gas in the fumigation treatment of broccoli to obtain the best effect of maintaining the fresh green of broccoli bulbs and extending the shelf life.

In order to study changes in the characteristic flavor of ultra-high temperature sterilized (UHT) milk under the influence of storage temperature and light, headspace solid phase microextraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS) was used to detect the volatile flavor components of the product. Descriptive sensory evaluation, orthogonal partial least squares-discriminant analysis (OPLS-DA) and entropy weight method were used to determine the relationship between major characteristic flavors and characteristic substances. The effects of temperature and light flux on the flavor changes of different formulations of UHT milk were analyzed, and a model for comprehensive analysis of the characteristic flavors of UHT milk was developed based on the effects of initial unsaturated fatty acid content, temperature and light flux. The results of this research provide support for the quality control of different formulations of UHT milk.

Purpose: To predict the shelf life of milk powder based on the change of oxygen concentration in the packaging headspace. Methods: The relative oxygen consumption rate was used to characterize the oxidation characteristics of whole milk powder, and the oxygen consumption threshold was determined by analyzing several oxidation indexes. Oxygen permeability of the packaging materials and oxidation characteristics of milk powder were integrated to characterize the change of headspace oxygen concentration, and a shelf life prediction model of milk powder was established based on the total oxygen consumption. The model was verified by accelerated storage test of polyethylene terephthalate/polyethylene packaged whole milk powder at 45 ℃. Results: The oxygen consumption threshold of whole milk powder was 0.041 47 mg/g. The experimental data of oxygen concentration in the packaging headspace during accelerated storage was consistent with the predicted data, and the relative deviation between the experimental and theoretical shelf life was 6.06%. Conclusions: The shelf life of whole milk powder can be predicted by the change of oxygen concentration in the packaging headspace.

Isoreticular metal-organic framework-3 (IRMOF-3), a porous coordination polymer, is an MOF material with the characteristics of a large specific surface area and adjustable pore size. Due to the existence of the active amino group (-NH2) on the organic ligand, IRMOF-3 has more extensive research and application potential. Herein, the main preparation methods of IRMOF-3 in existing research were compared and discussed first. Second, we classified and summarized the functionalization modification of IRMOF-3 based on different reaction mechanisms. In addition, the expanded research and progress of IRMOF-3 and their derivatives in catalysis, hydrogen storage, material adsorption and separation, carrier materials, and fluorescence detection were discussed from an application perspective. Moreover, the industrialization prospect of IRMOF-3 and the pressing problems in its practical application were analyzed and prospected. This review is expected to provide a reference for the design and application of more new nanomaterials based on IRMOF-3 to develop more advanced functional materials in industrial production and engineering applications. [ABSTRACT FROM AUTHOR]

The fully correlated frequency-independent Dirac–Coulomb–Breit Hamiltonian provides the most accurate description of electron–electron interaction before going to a genuine relativistic quantum electrodynamics theory of many-electron systems. In this work, we introduce a correlated Dirac–Coulomb–Breit multiconfigurational self-consistent-field method within the frameworks of complete active space and density matrix renormalization group. In this approach, the Dirac–Coulomb–Breit Hamiltonian is included variationally in both the mean-field and correlated electron treatment. We also analyze the importance of the Breit operator in electron correlation and the rotation between the positive- and negative-orbital space in the no-virtual-pair approximation. Atomic fine-structure splittings and lanthanide contraction in diatomic fluorides are used as benchmark studies to understand the contribution from the Breit correlation. [ABSTRACT FROM AUTHOR]

Regenerated cellulose membrane is a biomaterial obtained by activating, dissolving, solidifying, and regenerating cellulose powder using solvents of different polarities. It has the characteristics of high oxygen resistance and high strength. However, its low water vapor barrier and single function limit its application. In order to improve the water resistance of regenerated cellulose membranes and endow them with UV resistance, lignin was extracted from waste wheat straw using formic acid method. The extracted formic acid lignin (FAL) was added to the cellulose solution to prepare a series of regenerated lignocellulosic membranes (RC‐FAL) with different lignin contents. The results indicate that lignin can not only improve the water vapor barrier, tensile strength, and water resistance of the film, but also enhance the oxygen barrier and UV absorption of the film. Compared with pure cellulose film, the contact angle of lignocellulose film can be increased by 66.2%, the UV absorption rate can reach 100%, and the oxygen transmission coefficient has no significant effect. In this paper, a new kind of biological packaging material with high oxygen resistance, strong ultraviolet absorption, and water resistance was prepared by recycling waste wheat straw, it has a broad application prospect in the industrial production of packaging materials. [ABSTRACT FROM AUTHOR]

This research attempts to fabricate a novel type of pressure‐sensitive adhesive (PSA) tape utilizing epoxidized linseed oil (ELO) as the primary component in an effort to reduce reliance on petrochemical polymers. This raw material comes from the natural renewable resources, making this tape a more environmentally friendly choice in reducing impact on the environment and alleviating resource pressure. The ester groups on ELO are subjected to hydrolysis in order to yield a combination of epoxy linseed oil fatty acids (ELFAs) containing both epoxy and carboxyl groups. By controlling the temperature and catalyst conditions, the epoxy and carboxyl groups undergo a ring‐opening reaction, resulting in the self‐polymerization of the ELFA mixture and the formation of hydroxy‐functionalized polymers. These polymers are then applied as a coating on kraft paper and subsequently cut to produce PSA tapes. The tapes produced using this method exhibit a peak peel strength of 20.538 N per 25 mm. Moreover, the incorporation of glycerol ester of rosin serves to enhance the peel strength, resulting in a higher value of 21.883 N per 25 mm. The utilization of sealing the cardboard box by the tapes also serves as validation for the immense capabilities of the tapes in practical applications. [ABSTRACT FROM AUTHOR]

Auricularia cornea, jelly mushroom, is a popular ingredient of traditional Chinese cuisine. This study aimed at evaluating the growth, yield, biological efficiency, total phenolic and flavonoid contents, the antioxidant activity, elemental composition, and molecular structure of the wild and domesticated strain Ac24 and the commercially cultivated edible mushroom A. cornea strains Ac1, Ac3 and Ac15. Based on the weight of the fresh fruiting bodies of A. cornea strains, the maximum yield was obtained from commercial strain Ac1 (237.10 g), followed by Ac3 (224.47 g), Ac15 (158 g) and Ac24 (132.37 g), while the biological efficiency range of A. cornea strains was 52.94–94.84%, with significant differences among the A. cornea strains. Our results revealed that Ac24 contained the highest phenolic content (20.10 mg GAE · g−1), while the highest flavonoid content was found in Ac1 (35.13 mg CE · g−1). The maximum mineral contents and the strains were as follows: copper (7.2 mg · kg−1) and zinc (310 mg · kg−1) in Ac1, manganese (788 mg · kg−1) in Ac3 and iron (310 mg · kg−1) in Ac24. DPPH assay found maximum antioxidant activity in Ac24 (IC50 0.233 mg TX · mL−1), FRAP (591 mg TX · g−1) in Ac15, and erythrocyte haemolysis in Ac24. SEM-EDX and FTIR analyses verified the differences among A. cornea strains. The results revealed that wild, domesticated A. cornea strain Ac24 is a promising dietary source of natural antioxidants and is of high nutritional value, compared to commercially cultivated strains.