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Raman spectroscopy was applied with a high spectral resolution to a structural study of Influenza (type A) virus before and after its inoculation into Madin–Darby canine kidney cells. This study exploits the fact that the major virus and cell constituents, namely DNA/RNA, lipid, and protein molecules, exhibit peculiar fingerprints in the Raman spectrum, which clearly differed between cells and viruses, as well as before and after virus inoculation into cells. These vibrational features, which allowed us to discuss viral assembly, membrane lipid evolution, and nucleoprotein interactions of the virus with the host cells, reflected the ability of the virus to alter host cells' pathways to enhance its replication efficiency. Upon comparing Raman signals from the host cells before and after virus inoculation, we were also able to discuss in detail cell metabolic reactions against the presence of the virus in terms of compositional variations of lipid species, the formation of fatty acids, dephosphorylation of high‐energy adenosine triphosphate molecules, and enzymatic hydrolysis of the hemagglutinin glycoprotein. [ABSTRACT FROM AUTHOR]

A quantitative polarized Raman analysis of ferroelectric grain/domain orientation in LiSbO3 (LS-modified) (K0.5Na0.5)NbO3 (KNN) ceramics is presented, based on the analysis of the complex orientation dependence in space of their Raman-active modes. Complete sets of Raman tensor elements of Ag, and Eg phonon modes for orthorhombic/tetragonal structures of KNN have been determined. Through this spectroscopic algorithm, quantitative information could be extracted in terms of three Euler angles in space for KNN samples consisting of mixed phases, thus enabling quantitative visualization of the local distribution of grains/domains in the solid angle. As an application of the method, we quantitatively examined the unknown crystallographic grain orientation patterns on the surfaces of pure KNN and of KNN-0.05LS ceramics. These two samples were useful to clarify a polymorphic phase transition from the orthorhombic to the tetragonal phase taking place in the LS-modified KNN system. Thus, we demonstrated that polarized Raman spectroscopy is a valuable and efficient tool for nondestructive three-dimensional assessments of grain/domain orientation in ferroelectric materials with complex polymorphic structures. We believe that the data shown here represent a typical scenario encountered in grain/domain orientation assessments of piezoelectric perovskites. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An analytical procedure has been developed according to basic principles of electro-stimulated luminescence spectroscopy aimed at quickly visualizing with high spatial resolution the domain texture developed in tetragonal BaTiO3 (BT) materials. In the first part of the paper, the relative intensity of the cathodoluminescence (CL) emission has been systematically collected from different crystallographic planes of BT single-crystal and modeled as a function of anisotropic crystal properties. In this context, an analytical expression has been put forward for quantitatively describing the response function of the CL probe, which links the intensity emission to refractive indexes and absorption coefficients pertaining to different planes of the perovskitic crystal. In the second part of the paper, the CL method is applied to visualize with nanometer-scale resolution the domain texture developed in a polycrystalline BT sample. This study demonstrates that CL spectroscopy is a valuable and efficient tool for the assessment of domain orientation in ferroelectric materials. The CL method possesses both wide-range screening capacity and the scanning flexibility of conventional scanning electron microscopy, coupled with a spatial resolution that is comparable with that obtainable by scanning probe microscopy techniques. [ABSTRACT FROM AUTHOR]

In addressing the challenge of ships being prone to occlusion in multi‐target situations during ship target detection, leading to missed and false detections, this paper proposes an enhanced ship detection algorithm for YOLOv7‐tiny. The proposed method incorporates several key modifications. Firstly, it introduces the Convolutional Block Attention Module in the Backbone section of the original model, emphasizing position information while attending to channel features to enhance the network's ability to extract crucial information. Secondly, it replaces standard convolution with GSConv convolution in the Neck section, preserving detailed information and reducing computational load. Subsequently, the lightweight operator Content‐Aware ReAssembly of Features is employed to replace the original nearest‐neighbour interpolation, mitigating the loss of feature information during the up‐sampling process. Finally, the localization loss function, SIOU Loss, is utilized to calculate loss, expedite training convergence, and enhance detection accuracy. The research results indicate that the precision of the improved model is 91.2%, mAP@0.5 is 94.5%, and the F1‐score is 90.7%. These values are 3.7%, 5.5%, and 4.2% higher than those of the original YOLOv7‐tiny model, respectively. The improved model effectively enhances detection accuracy. Additionally, the improved model achieves an FPS of 145.4, meeting real‐time requirements. [ABSTRACT FROM AUTHOR]

Understanding the collision between kerosene droplets and coal particles in the bubble trailing vortex region is crucial for enhancing slurry conditioning. We found the area of the bubble trailing vortex region increased as the bubble size increased via the Fluent 6.3.26 software. A kerosene droplet velocity range of 0.074–0.106 m/s and a coal particle velocity range of 0.062–0.104 m/s were obtained if a bubble had a diameter of 0.3 mm. We employed a high‐speed motion acquisition system and observed the collision process, which was divided into two stages: Compression and Rebound. The critical motion distance increased as the kerosene droplet size increased, and sufficient kerosene droplet motion distance and enough kinetic energy normally resulted in a rebound phenomenon. The attenuation energy was almost positively linear to the initial energy, and the energy attenuation coefficient of the collision process was fitted to 0.626. Our results can provide valuable insight into mineral separation. [ABSTRACT FROM AUTHOR]

Studies regarding age‐related erectile dysfunction (ED) based on naturally aging models are limited by their high costs, especially for the acquisition of primary cells from the corpus cavernosum. Herein, d‐galactose (d‐gal) was employed to accelerate cell senescence, and the underlying mechanism was explored. As predominant functional cells involved in the erectile response, corpus cavernosum smooth muscle cells (CCSMCs) were isolated from 2‐month‐old rats. Following this, d‐gal was introduced to induce cell senescence, which was verified via β‐galactosidase staining. The effects of d‐gal on CCSMCs were evaluated by terminal deoxynucleoitidyl transferase dUTP nick‐end labeling (TUNEL), immunofluorescence staining, flow cytometry, western blot, and quantitative real‐time polymerase chain reaction (qRT‐PCR). Furthermore, RNA interference (RNAi) was carried out for rescue experiments. Subsequently, the influence of senescence on the corpus cavernosum was determined via scanning electron microscopy, qRT‐PCR, immunohistochemistry, TUNEL, and Masson stainings. The results revealed that the accelerated senescence of CCSMCs was promoted by d‐gal. Simultaneously, smooth muscle alpha‐actin (alpha‐SMA) expression was inhibited, while that of osteopontin (OPN) and Krüppel‐like factor 4 (KLF4), as well as fibrotic and apoptotic levels, were elevated. After knocking down KLF4 expression in d‐gal‐induced CCSMCs by RNAi, the expression level of cellular alpha‐SMA increased. Contrastingly, the OPN expression, apoptotic and fibrotic levels declined. In addition, cellular senescence acquired partial remission. Accordingly, in the aged corpus cavernosum, the fibrotic and apoptotic rates were increased, followed by downregulation in the expression of alpha‐SMA and the concurrent upregulation in the expression of OPN and KLF4. Overall, our results signaled that d‐gal‐induced accelerated senescence of CCSMCs could trigger fibrosis, apoptosis and phenotypic switch to the synthetic state, potentially attributed to the upregulation of KLF4 expression, which may be a multipotential therapeutic target of age‐related ED. [ABSTRACT FROM AUTHOR]

The selective conversion of methane to high value‐added chemicals under mild conditions is of great significance for the commercially viable and sustainable utilization of methane but remains a formidable challenge. Herein, we report a strategy for efficiently converting methane to acetic acid via CH3Cl as an intermediate. Up to 99.3 % acetic acid and methyl acetate (AA+MA) selectivity was achieved over pyridine‐pretreated MOR (MOR‐8) under moderate conditions of 523 K and 2.0 MPa. Water, conventionally detrimental to carbonylation reaction over zeolite catalysts, was conducive to the production of AA in the current reaction system. In the 100 h continuous test with the MOR‐8 catalyst, the average AA+MA selectivity remained over 98 %. AA was formed by carbonylation of methoxy groups within 8‐membered rings of MOR followed by hydrolysis. This strategy provided an approach for highly efficient utilization of methane to oxygenates under mild reaction conditions. [ABSTRACT FROM AUTHOR]

The selective conversion of methane to high value‐added chemicals under mild conditions is of great significance for the commercially viable and sustainable utilization of methane but remains a formidable challenge. Herein, we report a strategy for efficiently converting methane to acetic acid via CH3Cl as an intermediate. Up to 99.3 % acetic acid and methyl acetate (AA+MA) selectivity was achieved over pyridine‐pretreated MOR (MOR‐8) under moderate conditions of 523 K and 2.0 MPa. Water, conventionally detrimental to carbonylation reaction over zeolite catalysts, was conducive to the production of AA in the current reaction system. In the 100 h continuous test with the MOR‐8 catalyst, the average AA+MA selectivity remained over 98 %. AA was formed by carbonylation of methoxy groups within 8‐membered rings of MOR followed by hydrolysis. This strategy provided an approach for highly efficient utilization of methane to oxygenates under mild reaction conditions. [ABSTRACT FROM AUTHOR]

The transformation of methane into high value‐added chemicals such as aromatics provides a more desired approach towards sustainable chemistry but remains a critical challenge due to the low selectivity of aromatics and poor stability. Herein, we first report a coupling reaction of CH3Cl and CO (CCTA) based on methane conversion, which achieves extremely high aromatics selectivity (82.2 %) with the selectivity of BTX up to ca. 60 % over HZSM‐5. The promoting effects have been demonstrated on other zeolites especially 10‐membered rings (10 MR) zeolites. Multiple characterizations show that 2,3‐dimethyl‐2‐cyclopentene‐1‐one (DMCPO) is generated from acetyl groups and olefins. Furthermore, isotopic labeling analysis confirms that CO is inserted into the DMCPO and aromatics rings. A new aromatization mechanism is proposed, including the formation of the above intermediates, which conspicuously weakens the hydrogen transfer reaction, leading to a considerable increase of aromatics selectivity and a dramatic drop in alkanes. [ABSTRACT FROM AUTHOR]

The transformation of methane into high value‐added chemicals such as aromatics provides a more desired approach towards sustainable chemistry but remains a critical challenge due to the low selectivity of aromatics and poor stability. Herein, we first report a coupling reaction of CH3Cl and CO (CCTA) based on methane conversion, which achieves extremely high aromatics selectivity (82.2 %) with the selectivity of BTX up to ca. 60 % over HZSM‐5. The promoting effects have been demonstrated on other zeolites especially 10‐membered rings (10 MR) zeolites. Multiple characterizations show that 2,3‐dimethyl‐2‐cyclopentene‐1‐one (DMCPO) is generated from acetyl groups and olefins. Furthermore, isotopic labeling analysis confirms that CO is inserted into the DMCPO and aromatics rings. A new aromatization mechanism is proposed, including the formation of the above intermediates, which conspicuously weakens the hydrogen transfer reaction, leading to a considerable increase of aromatics selectivity and a dramatic drop in alkanes. [ABSTRACT FROM AUTHOR]

The multiple mutations of the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) virus have created variants with structural differences in both their spike and nucleocapsid proteins. While the functional relevance of these mutations is under continuous scrutiny, current findings have documented their detrimental impact in terms of affinity with host receptors, antibody resistance, and diagnostic sensitivity. Raman spectra collected on two British variant sub‐types found in Japan (QK002 and QHN001) are compared with that of the original Japanese isolate (JPN/TY/WK‐521), and found bold vibrational differences. These included: i) fractions of sulfur‐containing amino acid rotamers, ii) hydrophobic interactions of tyrosine phenol ring, iii) apparent fractions of RNA purines and pyrimidines, and iv) protein secondary structures. Building upon molecular scale results and their statistical validations, the authors propose to represent virus variants with a barcode specially tailored on Raman spectrum. Raman spectroscopy enables fast identification of virus variants, while the Raman barcode facilitates electronic recordkeeping and translates molecular characteristics into information rapidly accessible by users. [ABSTRACT FROM AUTHOR]

Direct propane dehydrogenation (PDH) is an attractive on‐purpose strategy for propylene production. Compared with high‐priced Platinum and toxic Chromium oxide, ZnO based catalysts attract wide attention due to its low‐cost and environment‐friendly character. Herein we report silicalite‐1 supported ZnO catalysts for PDH reaction. They exhibited an excellent catalytic performance. The catalyst with 5 wt% Zn exhibited the best propane yield with propane conversion reaching 49 % and propylene selectivity around 90 % at a space velocity of 5000 ml ⋅ g−1 ⋅ h−1. Characterization with N2 adsorption, XRD, SEM, TEM, EDS, NH3‐TPD, UV–vis, XPS, 29Si MAS NMR, FT‐IR, Py‐IR and TGA reveal that the high activity and stability can be attributed to the dispersed ZnO species due to the interaction between silanol nests of silicalite‐1 support and ZnO species. This study may open a promising way for development of highly efficient PDH catalysts. [ABSTRACT FROM AUTHOR]

Abstract: The conversion of methanol into aromatics over unmodified H‐ZSM‐5 zeolite is generally not high because the hydrogen transfer reaction results in alkane formation. Now circa 80 % aromatics selectivity for the coupling reaction of methanol and carbon monoxide over H‐ZSM‐5 is reported. Carbonyl compounds and methyl‐2‐cyclopenten‐1‐ones (MCPOs), which were detected in the products and catalysts, respectively, are considered as intermediates. The latter species can be synthesized from the former species and olefins. 13C isotope tracing and 13C liquid‐state NMR results confirmed that the carbon atoms of CO molecules were incorporated into MCPOs and aromatic rings. A new aromatization mechanism that involves the formation of the above intermediates and co‐occurs with a dramatically decreased hydrogen transfer reaction is proposed. A portion of the carbons in CO molecules are incorporated into aromatic, which is of great significance for industrial applications. [ABSTRACT FROM AUTHOR]

Abstract: The conversion of methanol into aromatics over unmodified H‐ZSM‐5 zeolite is generally not high because the hydrogen transfer reaction results in alkane formation. Now circa 80 % aromatics selectivity for the coupling reaction of methanol and carbon monoxide over H‐ZSM‐5 is reported. Carbonyl compounds and methyl‐2‐cyclopenten‐1‐ones (MCPOs), which were detected in the products and catalysts, respectively, are considered as intermediates. The latter species can be synthesized from the former species and olefins. 13C isotope tracing and 13C liquid‐state NMR results confirmed that the carbon atoms of CO molecules were incorporated into MCPOs and aromatic rings. A new aromatization mechanism that involves the formation of the above intermediates and co‐occurs with a dramatically decreased hydrogen transfer reaction is proposed. A portion of the carbons in CO molecules are incorporated into aromatic, which is of great significance for industrial applications. [ABSTRACT FROM AUTHOR]

Despite the recent introduction of mass detection techniques, ultraviolet detection is still widely applied in the field of the chromatographic analysis of natural medicines. Here, a neural network cascade model consisting of nine small artificial neural network units was innovatively developed to predict the chromatographic sequence of natural compounds by integrating five molecular descriptors as the input. A total of 117 compounds of known structure were collected for model building. The order of appearance of each compound was determined in gradient chromatography. Strong linear correlation was found between the predicted and actual chromatographic position orders (Spearman's rho = 0.883, p < 0.0001). Application of the model to the external validation set of nine natural compounds was shown to dramatically increase the prediction accuracy of the real chromatographic order of multiple compounds. A case study shows that chromatographic sequence prediction based on a neural network cascade facilitated compound identification in the chromatographic fingerprint of Radix Salvia miltiorrhiza. For natural medicines of known compound composition, our method provides a feasible means for identifying the constituents of interest when only ultraviolet detection is available. [ABSTRACT FROM AUTHOR]

Keywords: Aromatics; Carbon Monoxide; Chloromethane; HZSM-5; Methane Conversion EN Aromatics Carbon Monoxide Chloromethane HZSM-5 Methane Conversion 1 1 1 03/16/22 20220321 NES 220321 B The coupling of CH SB 3 sb Cl with CO b over H-zeolites is an efficient reaction strategy for the transformation of methane into aromatics, which ensures the sustainable development of natural gas in an environmental pathway. Aromatics, Carbon Monoxide, Chloromethane, HZSM-5, Methane Conversion Inside Back Cover: Highly Enhanced Aromatics Selectivity by Coupling of Chloromethane and Carbon Monoxide over H-ZSM-5 (Angew. [Extracted from the article]

Innenrücktitelbild: Highly Enhanced Aromatics Selectivity by Coupling of Chloromethane and Carbon Monoxide over H-ZSM-5 (Angew. Keywords: Aromatics; Carbon Monoxide; Chloromethane; HZSM-5; Methane Conversion EN Aromatics Carbon Monoxide Chloromethane HZSM-5 Methane Conversion 1 1 1 03/16/22 20220321 NES 220321 B Die Kupplung von CH SB 3 sb Cl mit CO b über H-Zeolithen ist eine effiziente Reaktion für die Umwandlung von Methan in Aromaten, die die nachhaltige Entwicklung von Erdgas auf einem umweltfreundlichen Weg gewährleistet. Methane Conversion, Aromatics, Carbon Monoxide, Chloromethane, HZSM-5. [Extracted from the article]

The transformation of methane into high value‐added chemicals such as aromatics provides a more desired approach towards sustainable chemistry but remains a critical challenge due to the low selectivity of aromatics and poor stability. Herein, we first report a coupling reaction of CH3Cl and CO (CCTA) based on methane conversion, which achieves extremely high aromatics selectivity (82.2 %) with the selectivity of BTX up to ca. 60 % over HZSM‐5. The promoting effects have been demonstrated on other zeolites especially 10‐membered rings (10 MR) zeolites. Multiple characterizations show that 2,3‐dimethyl‐2‐cyclopentene‐1‐one (DMCPO) is generated from acetyl groups and olefins. Furthermore, isotopic labeling analysis confirms that CO is inserted into the DMCPO and aromatics rings. A new aromatization mechanism is proposed, including the formation of the above intermediates, which conspicuously weakens the hydrogen transfer reaction, leading to a considerable increase of aromatics selectivity and a dramatic drop in alkanes. [ABSTRACT FROM AUTHOR]

Cubic gallium oxynitride is synthesized by solvothermal processing of a gallium ethylene diamine complex and H2O (autoclave, 200 °C, 1 d). [ABSTRACT FROM AUTHOR]