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The quaternary alloys La0.8-xCexMg0.2Ni3.8 (x=0, 0.1,0.3,0.5) were prepared by induction melting, and the effects of partial substitution of Ce for La on the phase structure and electrochemical performances of super lattice La4MgNi19 negative materials were investigated. Results show that La4MgNi19 alloys contain LaNi5 phase, (La,Mg)2Ni7(3R-Ce2Ni7 and 2H-Gd2Co7) phase, (La,Mg)5Ni19 (3R-Ce5Co19) phase. The 2H-Pr5Co19 type phase appears while (La,Mg)2Ni7 phase disappears, after partial substitution of Ce for La. The increase of Ce element substitution has led to an obvious increase of the abundance of A5B19 phase and decrease of AB5 phase accordingly. Ce contributes to the formation of A5B19 phase, especially 2H-Pr5Co19 type phase. With the increase of Ce content from 0 to 0.5, the maximum discharge capacity of alloy electroded increases firstly and then decreased. The x=0.1 alloy exhibits a maximum discharge capacity of 380.36 mAh/g. It is also found that this substitution has caused a significant increase in the activation number, the cyclic stability, high-rate discharge ability. The well performance demonstrates that it is the hydrogen diffusion in the alloy that controls the high rate discharge.

The quaternary alloys La0.8-xCexMg0.2Ni3.8 (x=0, 0.1,0.3,0.5) were prepared by induction melting, and the effects of partial substitution of Ce for La on the phase structure and electrochemical performances of super lattice La4MgNi19 negative materials were investigated. Results show that La4MgNi19 alloys contain LaNi5 phase, (La,Mg)2Ni7(3R-Ce2Ni7 and 2H-Gd2Co7) phase, (La,Mg)5Ni19 (3R-Ce5Co19) phase. The 2H-Pr5Co19 type phase appears while (La,Mg)2Ni7 phase disappears, after partial substitution of Ce for La. The increase of Ce element substitution has led to an obvious increase of the abundance of A5B19 phase and decrease of AB5 phase accordingly. Ce contributes to the formation of A5B19 phase, especially 2H-Pr5Co19 type phase. With the increase of Ce content from 0 to 0.5, the maximum discharge capacity of alloy electroded increases firstly and then decreased. The x=0.1 alloy exhibits a maximum discharge capacity of 380.36 mAh/g. It is also found that this substitution has caused a significant increase in the activation number, the cyclic stability, high-rate discharge ability. The well performance demonstrates that it is the hydrogen diffusion in the alloy that controls the high rate discharge.

Using deep learning models and attention mechanisms to classify fine-grained emotions of Chinese microblogs has become a research hotspot.However,the existing attention mechanisms consider the impact of words on words,and lack effective integration of the various dimensional characteristics of the words themselves (such as word meaning,part of speech,semantics and other characteristic information).In order to solve this problem,the paper proposes a dual weight mechanism WDWM (word and dimension weight mechanism),and combines it with the GCN model based on the analytical dependency tree,so that it can not only select the words that contain key information in each microblog,but also extract the important dimensional characteristics of the word and effectively integrate multiple dimensional characteristics of words,so as to capture more rich feature information.The F measure of fine-grained sentiment classification of Chinese microblogs combining dual weight mechanism and graph convolutional neural network(WDWM-GCN) reaches 84.02%,which is 1.7% higher than the latest algorithm proposed by WWW in 2020,which further proves that WDWM-GCN can effectively integrate the multi-dimensional characteristics of words and capture rich feature information.In the experiment on the classification of Sogou news data set,after the BERT model is addedto the WDWM mechanism,the classification effect is further improved,which fully provs that the WDWM has a significant improvement on the text classification model.

Molecular perovskite energetic material DAP-4 was synthesized by chemical methods, and it was characterized by using SEM, EDS, XRD, IR, XPS, and elemental analysis. The enthalpy of formation (AHf) and the thermal decomposition per¬formance of DAP-4 were tested by using the oxygen bomb calorimeter and DSC technology. Its mechanical sensitivity, detona¬tion performance, and combustion performance were also carried out. The DAP-4 was used in CMDB propellant, and the con¬stant volume combustion and the constant pressure combustion performance were tested. The results show that the enthalpy of formation of DAP-4 was determined as 278. 6kJ/mol. At a heating rate of 20 °C /min, the peak temperature of thermal de-composition reached 392. 5 °C, the activation energy of thermal decomposition (fK) was 247. 2kJ/mol, and the critical tem¬perature of thermal explosion ( Tb) reached 631. 6K, which was much higher than that of HMX. The impact sensitivity of DAP-4 was similar to that of TNT, and the friction sensitivity was closed to CL-20. The detonation velocity of DAP-4 was as high as that of RDX. The chemical energy storage, work capacity, and metal acceleration ability of DAP-4 and its mixed explo¬sives were significantly higher than those of RDX and HMX, which was closed to CL-20. The constant volume combustion ex¬periment showed that the CMDB-1 propellant containing DAP-4 had the fastest burning rate, the highest combustion pressure, and the highest pressurization rate. The constant pressure combustion data showed that the combustion temperature of CMDB-1 propellant was the highest, which can reach 3 501 °C . [ABSTRACT FROM AUTHOR]

Simple Summary: Toxoplasma gondii is a zoonotic pathogenic apicomplexan parasite that infects approximately one third of the global population. In immunosuppressed individuals, the infection may be fatal. Current anti-toxoplasmosis drugs have low efficacy and cause side effects, and no vaccine is available to prevent human toxoplasmosis. To search for potential virulence genes of T. gondii with a view to serving as new drug or vaccine targets for toxoplasmosis, we selected 11 genes of interest (GOIs), which were tentative microneme proteins (MICs) with unknown functions, and applied the CRISPR-Cas9 system to construct 11 epitope tagging strains and gene knockout strains to explore their intracellular localization and biological functions. The results showed that nine tentative MICs were localized or partially localized in the microneme, one GOI was localized in endoplasmic reticulum, and another GOI was localized in the dense granule. Deletion of the 11 genes showed no significant effect on the in vitro growth and virulence of the tachyzoites of T. gondii type I RH strain. This study investigated the role of the 11 tentative mics in T. gondii tachyzoites, which expanded the knowledge of the functionally unknown genes of T. gondii. In the future, roles of these genes in other life stages and other genotypes of T. gondii will be explored. Toxoplasma gondii, a pathogenic apicomplexan parasite, infects approximately one third of the world's population and poses a serious threat to global public health. Microneme proteins (MICs) secreted by the microneme, an apical secretory organelle of T. gondii, play important roles in the invasion, motility, and intracellular survival of T. gondii. In this study, we selected 11 genes of interest (GOIs) of T. gondii, tentative MICs predicted to be localized in micronemes, and we used the CRISPR-Cas9 system to construct epitope tagging strains and gene knockout strains to explore the localization and function of these 11 tentative MICs. Immunofluorescence assay showed that nine tentative MICs (TGME49_243930, TGME49_200270, TGME49_273320, TGME49_287040, TGME49_261710, TGME49_205680, TGME49_304490, TGME49_245485, and TGME49_224620) were localized or partially localized in the microneme, consistent with the prediction. However, TGME49_272380 and TGME49_243790 showed different localizations from the prediction, being localized in the endoplasmic reticulum and the dense granule, respectively. Further functional characterization of the 11 RHΔGOI strains revealed that deletion of these 11 GOIs had no significant effect on plaque formation, intracellular replication, egress, invasion ability, and virulence of T. gondii. Although these 11 GOIs are not essential genes for the growth and virulence of tachyzoites of type I RH strain, they may have potential roles in other developmental stages or other genotypes of T. gondii. Thus, further research should be performed to explore the possible role of the nine mics and the other two GOIs in other life cycle stages and other genotypes of T. gondii. [ABSTRACT FROM AUTHOR]

Eukaryotic translation initiation factors (eIFs) are crucial for initiating protein translation and ensuring the correct assembly of mRNA-ribosomal subunit complexes. In this study, we investigated the effects of deleting six eIFs in the apicomplexan parasite Toxoplasma gondii using the CRISPR-Cas9 system. We determined the subcellular localization of these eIFs using C-terminal endogenous tagging and immunofluorescence analysis. Four eIFs (RH::315150-6HA, RH::286090-6HA, RH::249370-6HA, and RH::211410-6HA) were localized in the cytoplasm, while RH::224235-6HA was localized in the apicoplast. Additionally, RH::272640-6HA was found in both the basal complex and the cytoplasm of T. gondii. Functional characterization of the six RHΔeIFs strains was conducted using plaque assay, cell invasion assay, intracellular growth assay and egress assay in vitro, and virulence assay in mice. Disruption of five eIF genes (RHΔ315150, RHΔ272640, RHΔ249370, RHΔ211410, and RHΔ224235) did not affect the ability of the T. gondii RH strain to invade, replicate, form plaques and egress in vitro, or virulence in Kunming mice (p > 0.05). However, the RHΔ286090 strain showed slightly reduced invasion efficiency and virulence (p < 0.01) compared to the other five RHΔeIFs strains and the wild-type strain. The disruption of the TGGT1_286090 gene significantly impaired the ability of tachyzoites to differentiate into bradyzoites in both type I RH and type II Pru strains. These findings reveal that the eukaryotic translation initiation factor TGGT1_286090 is crucial for T. gondii bradyzoite differentiation and may serve as a potential target for drug development and an attenuated vaccine against T. gondii. [ABSTRACT FROM AUTHOR]

In the paper, a magneto-mechanic hysteresis model for giant magnetostrictive materials is suggested by considering the effect of the domain rotation and domain wall motion on the magnetization process under prestress and the applied magnetic field. The coercive force, which is magneto-mechanic dependent, is proposed instead of a pinning constant in the Jiles–Atherton model. The model can well predict the characteristics of a magnetization-applied field curve and magnetostrictive strain-applied field curve shown in the experiment, especially the "overturn phenomenon" under different compressive prestresses. Furthermore, the effect of the microstructure parameter, such as the ratio of the domain wall thickness to the internal stress wavelength, the amplitude of internal stress, the ratio of the domain wall thickness to the inclusion radius, and inclusion consistency, on coercive force under applied prestress can also be described by the model. The comparison between the results predicted by the model and experiment shows that the model is suited for a wide-ranging applied magnetic field. [ABSTRACT FROM AUTHOR]

Acrylamides are a class of important organic compounds that play key roles in biomedical chemistry, materials science, life science, and other fields. Due to the strong electron‐withdrawing effect of trifluoromethyl, the synthesis of trifluoromethylated acrylamides, especially those containing double bonds, has long been a challenge. Here, we report an example of the formation of trifluoromethyl acrylamides through palladium catalyzedcarbonylation of fluorinated olefins. By optimizing the reaction conditions, we can obtain different amide compounds, including alkyl acrylamides. aromatic acrylamides and heterocyclic acrylamides. This method has good substrate adaptability and functional group tolerance,so it is expected to be used in the synthesis of key amides in the fields of medicine and other fields. [ABSTRACT FROM AUTHOR]

Recently, the widespread use of nanocatalytic materials has contributed to an enormous improvement in the performance of energetic materials, especially, highly dispersed nanomaterials. However, the lack of quantitative methods for analyzing the dispersion of nanomaterials limits their further widespread use. Although various techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), etc. are used to analyze the relative dispersion of nanomaterials, it is not possible to quantitatively analyze their dispersion. Therefore, there has been an effort to develop new methods for the quantitative analysis of nanocatalytic materials. Fortunately, we were able to analyze the dispersion of nanocatalytic materials using the difference in their UV absorbance. More importantly, we established the corresponding difference equation to quantify the dispersion of nanocatalytic materials, which is capable of quantifying the dispersion of nano-Fe2O3 in nano-Fe2O3–ultrafine AP composites. The accuracy of the difference equation was verified using a variety of techniques and the desired results were obtained. Based on the above conclusions, the quantitative analysis method for the dispersion of nanomaterials that we established is expected to be widely used and promote the development of energetic materials. [ABSTRACT FROM AUTHOR]