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MB_(8)^(0/-)(M=Li、Na、Rb、Cs)团簇的几何结构和电子特性的研究

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原子与分子物理学报 2024年第5期41卷 85-93页

作者：李媛媛胡燕飞袁玉全董晓林四川轻化工大学物理与电子工程学院自贡643000 成都理工大学数理学院成都610059

本文结合CALYPSO软件和密度泛函理论,详细研究了MB_(8)^(0/-)(M=Li、Na、Rb、Cs)团簇的几何结构和成键特性.结构分析结果表明,MB_(8)^(0/-)团簇的基态结构都具有相似的几何构型,均为七棱锥状结构,并且随着掺杂原子的原子序数的增加,其M-... 详细信息

本文结合CALYPSO软件和密度泛函理论,详细研究了MB_(8)^(0/-)(M=Li、Na、Rb、Cs)团簇的几何结构和成键特性.结构分析结果表明,MB_(8)^(0/-)团簇的基态结构都具有相似的几何构型,均为七棱锥状结构,并且随着掺杂原子的原子序数的增加,其M-B键的键长呈增加的趋势.通过稳定性分析,我们发现LiB_(8)^(-)团簇的最高占据分子轨道与最低未占据分子轨道之间的能隙(HOMO-LOMO能隙)以及结合能(E_(b))最大,因此这个团簇是体系中相对稳定的结构.电荷转移分析表明,掺杂的碱金属原子在所研究体系中充当着电子供体的角色.最后,成键分析的结果显示,LiB_(8)^(-)团簇的稳定性来源于B原子的2p轨道以及Li原子的2s和2p轨道在HOMO和LUMO的高贡献;适应性自然密度划分分析显示,B和Li原子都参与了成键,这同样有利于LiB_(8)^(-1)团簇的高稳定性的形成.希望我们的工作能为进一步研究碱金属掺杂硼团簇提供指导和帮助.

关键词： CALYPSO 第一性原理掺杂硼团簇稳定性分析

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NUMERICAL SIMULATION FOR SHALLOW FLOW AND POLLUTANT DISPERSION BASED ON QUAD-TREE MESHES

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Journal of Hydrodynamics 2006年第2期18卷 161-169页

作者： LIU xiao-dong HUA Zu-lin State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow LakesCollege of Environmental Science and Engineering Hohai UniversityNanjing 210098 China

A 2D depth-averaged flow-pollutant coupled model based on quad-tree meshes was established to accurately simulate flows in water areas with irregular natural boundaries in this paper. The grids were generated by recursive subdivision about seeding points. A new neighbor-finding algorithm was presented. The governing equations were discrctized in collocated conservative variables by using the finite volume method, and the normal flux of mass, momentum and pollutants across the interlace between cells were computed by a Godunov-type Flux Difference Splitting （FDS） scheme. The model was applied to simulate flow fields around a groin. The computed values are in agreement with observed data. The results indicate that quad-tree meshes have fine local resolution, high efficiency and easy local refinement. It is clear that the quad-tree grid model can offer gains in efficiency when applied to complex flow domains or strong shear flows. Finally the model is applied to flow fields and concentration fields simulation in Jiangsu Haizhou Bay. The simulated polluted area is matched well with observations. Therefore, this model can be used to predict flow and concentration fields of actual water area with irregular natural land boundaries.

关键词： quad-tree grid shallow flow numerical simulation dispersion Godunov-type

Conditional selection with CNN augmented transformer for multimodal affective analysis

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 917-931页

作者： Jianwen Wang Shiping Wang Shunxin xiao Renjie lin Mianxiong dong Wenzhong Guo College of Computer and Data Science Fuzhou UniversityFuzhouChina College of Computer and Cyber Security Fujian Normal UniversityFuzhouChina Key Laboratory of Network Computing and Intelligent Information Processing Fuzhou UniversityFuzhouChina Digital Fujian Institute of Big Data Security Technology Fujian Normal UniversityFuzhouChina Department of Sciences and Informatics Muroran Institute of TechnologyMuroranJapan

Attention mechanism has been a successful method for multimodal affective analysis in recent years. Despite the advances, several significant challenges remain in fusing language and its nonverbal context information. One is to generate sparse attention coefficients associated with acoustic and visual modalities, which helps locate critical emotional se-mantics. The other is fusing complementary cross‐modal representation to construct optimal salient feature combinations of multiple modalities. A Conditional Transformer Fusion Network is proposed to handle these problems. Firstly, the authors equip the transformer module with CNN layers to enhance the detection of subtle signal patterns in nonverbal sequences. Secondly, sentiment words are utilised as context conditions to guide the computation of cross‐modal attention. As a result, the located nonverbal fea-tures are not only salient but also complementary to sentiment words directly. Experi-mental results show that the authors’ method achieves state‐of‐the‐art performance on several multimodal affective analysis datasets.

关键词： affective computing data fusion information fusion multimodal approaches

Characteristics and stability of oxide+carbonitride in H13 steel at 1250℃

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Journal of Iron and Steel Research International 2024年第1期31卷 134-142页

作者： xiao-lin Sun Han-jie Guo Jing Guo Fei Wang dong Xu Gao-yang Song Shuai Wang School of Materials Science and Engineering Hebei University of EngineeringHandan056038HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China High Temperature Materials Research Institute Central Iron and Steel Research Institute Co.Ltd.Beijing100081China Technology Innovation Center for High Quality Cold Heading Steel of Hebei Province Hebei University of EngineeringHandan056038HebeiChina

The morphology,size,quantity,and composition of complex oxide+carbonitride in H13 steel held at 1250℃for 5,10,and 15 h were *** results show that the ratio and number of complex carbonitrides with cores in H13 steel are gradually increased when holding at 1250℃compared with those in the original H13 steel,and the core size *** are one or more oxide cores in(Ti_(x),V_(1-x))(Cy,N_(1-y)),including xCaO·zAl_(2)O_(3),xCaO·yMgO·zAl_(2)O_(3),and CaO after holding at 1250℃,in addition to MgO·Al_(2)O_(3)and Al_(2)O_(3)in the original *** equilibrium temperature for(Ti_(x),V_(1-x))(Cy,N_(1-y))precipitation at the solidification front and decomposition in the solid state was theoretically analyzed,which was affected by the x value and the product of Ti and N contents in H13 ***,the composition of(Ti_(x),V_(1-x))(Cy,N_(1-y))is influenced by the oxide *** is convinced that(Ti_(x),V_(1-x))(Cy,N_(1-y))with oxide cores has a higher stability,especially for oxides with a high Al_(2)O_(3)*** treatment at high temperature facilitates a more reasonable analysis of oxide+carbonitride,and the generation mechanism of oxide+carbonitride was discussed.

关键词： Complex carbonitride Decomposition Oxide core Characteristic Stability

Introducing electrolytic electrochemical polymerization for constructing protective layers on Ni-rich cathodes of Li-ion batteries

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Rare Metals 2024年第6期43卷 2536-2545页

作者： lin-Tao Dou Bei Li Hao-Long Nie dong-dong xiao Chao-Qun Shang xiao-Min Wang Zhan-Hui Zhang Katerina E.Aifantis Pu Hu School of Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China Huairou Division Institute of PhysicsChinese Academy of SciencesBeijing 101400China Department of Mechanical and Aerospace Engineering University of FloridaGainesvilleFL 32603USA

lini_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)is the most promising cathode for high-energy Li-ion batteries,despite its poor cycling stability that originates from the reactions that occur with the ***,to solve this interfacial issue,a facile electrolytic electrochemical polymerization process was introduced in this paper,and a uniform conductive electrolyte interface(polyaniline)was successfully constructed on the surface of the NCM811 porous electrode(PANI-NCM),which facilitated the charge transfer during charge/*** side reactions at the interface between the cathode and the electrolyte are suppressed,and thereby,the cycling performance and rate capability are considerably ***-NCM delivers an initial capacity of 157.2 mAh·g^(-1)as well as excellent cyclability(capacity retention of 88%after 500 cycles at 2C),whereas the capacity of the bare NCM811 has dropped to 31.3 mAh·g^(-1).In addition,polypyrrole and polythiophene also can be formed through electrolytic electrochemical polymerization process,which provides a practicable tactic to modify the interfacial stability of cathodes for high-energy Li-ion batteries.

关键词： Lithium-ion battery Ni-rich cathode In-situ polymerization Conductive polymer Electrochemical performance

Influencing factors and risk prediction model for emergence agitation after general anesthesia for primary liver cancer

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2194-2201页

作者： Shu-Shu Song Li lin Li Li xiao-dong Han Department of Anesthesia and Surgery Wenzhou Central HospitalWenzhou 325099Zhejiang ProvinceChina

BACKGROUND General anesthesia is commonly used in the surgical management of gastrointestinal tumors;however,it can lead to emergence agitation(EA).EA is a common complication associated with general anesthesia,often characterized by behaviors,such as crying,struggling,and involuntary limb movements in *** treatment is delayed,there is a risk of incision cracking and bleeding,which can significantly affect surgical ***,having a proper understanding of the factors influencing the occurrence of EA and implementing early preventive measures may reduce the incidence of agitation during the recovery phase from general anesthesia,which is beneficial for improving patient *** To analyze influencing factors and develop a risk prediction model for EA occurrence following general anesthesia for primary liver *** Retrospective analysis of clinical data from 200 patients who underwent hepatoma resection under general anesthesia at Wenzhou Central Hospital(January 2020 to December 2023)was ***-surgery,the Richmond Agitation-Sedation Scale was used to evaluate EA presence,noting EA incidence after general *** were categorized by EA presence postoperatively,and the influencing factors were analyzed using logistic regression.A nomogram-based risk prediction model was constructed and evaluated for differentiation and fit using receiver operating characteristics and calibration *** EA occurred in 51(25.5%)*** analysis identified advanced age,American Society of Anesthesiologists(ASA)grade Ⅲ,indwelling catheter use,and postoperative pain as risk factors for EA(P<0.05).Conversely,postoperative analgesia was a protective factor against EA(P<0.05).The area under the curve of the nomogram was 0.972[95%confidence interval(CI):0.947-0.997]for the training set and 0.979(95%CI:0.951-1.000)for the test ***-Lemeshow test showed a good fit(χ^(2)=5.483,P=0.705),and calibration curves showed

关键词： Primary hepatocellular carcinoma resection General anesthesia Emergence agitation Risk factors Forecast Nomograph

EUS、白光内镜、ME-NBI在早期胃癌浸润深度诊断中的效果

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河北医科大学学报 2024年第2期45卷 141-146页

作者：梁慧霞胡颖华戚美娅闫再宏王醒董晓琳河北中石油中心医院消化科河北廊坊065000

目的探讨超声内镜(endoscopic ultrasound,EUS)、白光内镜(white light endoscopy,WLI)、放大内镜结合窄带显像(enlarged endoscopy combined with narrowband imaging,ME-NBI)在早期胃癌浸润深度诊断中的效果。方法选取河北中石油中心医院治疗的早期胃癌患者78例。同时选取正常体检者60例为对照组,比较EUS、WLI、ME-NBI及三者联合诊断浸润深度的准确率差异。采用多因素Logistic回归模型分析建立数据模型分析影响EUS、WLI和ME-NBI三者联合诊断早期胃癌浸润深度准确率的相关因素。结果病理结果显示:T1a期患者50例,T1b期患者28例。在T1a病变中,EUS、WLI和ME-NBI三者联合诊断准确率为92.00%,明显高于EUS、WLI单独诊断(P<0.05)。在T1b病变中,EUS、WLI和ME-NBI三者联合诊断准确率为92.86%,明显高于WIL单独诊断(P<0.05)。病变大小≥2 cm患者EUS、WLI和ME-NBI三者联合诊断浸润深度准确率为77.29%,明显低于病变大小<2 cm患者(P<0.05)。凹陷型形态患者EUS、WLI和ME-NBI三者联合诊断浸润深度准确率为66.67%,明显低于隆起型、平坦型形态患者(P<0.05)。贲门胃底区病变EUS、WLI和ME-NBI三者联合诊断浸润深度准确率76.92%明显低于胃体区病变、胃窦幽门区病变(P<0.05)。多因素Logistic回归分析显示:病变大小、病变形态、病变部位是EUS、WLI和ME-NBI三者联合诊断浸润深度准确率的影响因素(P<0.05)。结论EUS、WLI和ME-NBI三者联合诊断早期胃癌浸润深度有较高的价值,三者联合诊断准确率受病变大小、病变形态、病变部位的影响。

关键词：胃肿瘤腔内超声检查白光内镜放大内镜

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Significantly Enhanced Energy Storage Performances of PEI-based Composites Utilizing Surface Functionalized ZrO_(2) Nanoparticles for High-Temperature Application

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Chinese Journal of Polymer Science 2024年第3期42卷 322-332,I0006页

作者： Qing-Qing Liu Qiu-Hao lin xiao-dong Qi Nan Zhang Ting Huang Jing-Hui Yang Yong Wang School of Chemistry Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of Advanced Technologies of Materials Ministry of Education of ChinaSouthwest Jiaotong UniversityChengdu 610031China

Polymer dielectrics with a high energy density and an available energy storage capacity have been playing an important role in advanced electronics and power systems. Nevertheless, the use of polymer dielectrics in harsh environments is limited by their low energy density at high temperatures. Herein, zirconium dioxide(ZrO_(2)) nanoparticles were decorated with amino group utilizing 4,4-methylenebis(phenyl isocyanate)(AMEO) and successfully incorporated into polyetherimide(PEI) matrix. The dielectric properties, breakdown strength, and energy storage performances of PEI/ZrO_(2)-AMEO nanocomposites were investigated from 25 ℃ to 150 ℃. It is found that the combination of moderate bandgap ZrO_(2) with modest dielectric constant and polar groups at interface with deep trap can offer an available strategy to simultaneously increase the dielectric constant and breakdown strength of polymer dielectrics. As a result, the composites containing ZrO_(2)-AMEO exhibit excellent energy storage performance at elevated temperatures. Specially, the PEI-based composites with 3 vol% ZrO_(2)-AMEO display a maximum discharged energy density(U_(d)) of 3.1 J/cm^(3) at 150 ℃, presenting 90% higher than that of neat PEI. This study may help to better develop the polymer-based dielectric composite applied at elevated temperatures.

关键词： Polyetherimide High temperature dielectric ZrO_(2) Interface

Comprehensive study on the spatial distribution of heavy metals and their environmental risks in high-sulfur coal gangue dumps in China

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Journal of Environmental Sciences 2024年第2期136卷 486-497页

作者： Yingbo dong Huan Lu Hai lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in *** spatial distribution and environment risk assessment are extremely important for the management and remediation of *** soil samples were collected from the high-sulfur CG site in northern China and analyzed for six *** results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment *** semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of ***,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more *** spatial autocorrelation indicated that all HMs had strong spatial *** BCR sequential extraction was employed to qualify the geochemical fractions of *** data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)*** correlation analysis showed that pH was the main control factor affecting the non-residue fractions of ***,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of ***,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.

关键词： High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment