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乙酰丙酮铱Ir(acac)_(3)电子结构及光学性质的理论研究

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原子与分子物理学报 2025年第1期42卷 1-7页

作者：樊依佳蔚娇娇郭家成陈扬尹杜恭贺西北工业大学伦敦玛丽女王大学工程学院西安710129 西安邮电大学理学院西安710121

乙酰丙酮铱是一种由过渡金属Ir与乙酰丙酮酸(acetylcaetonato)有机部分组成的过渡金属有机配合物,它是一种重要的绿光磷光材料,同时其也是多种铱系发光材料的组成部分.采用密度泛函理论(DFT)对Ir(acac)_(3)单体及其二聚物的基态几何结... 详细信息

乙酰丙酮铱是一种由过渡金属Ir与乙酰丙酮酸(acetylcaetonato)有机部分组成的过渡金属有机配合物,它是一种重要的绿光磷光材料,同时其也是多种铱系发光材料的组成部分.采用密度泛函理论(DFT)对Ir(acac)_(3)单体及其二聚物的基态几何结构进行了优化,在此基础上考察了它们的振动和红外光谱,并使用CIS方法对它们的激发态性质进行了理论研究.计算得到的单体和二聚物的吸收光谱均在紫外波段,单体的主要吸收峰有260 nm,350 nm,414 nm,二聚物的主要吸收峰有299 nm,353 nm,401 nm.计算得到了二者在乙腈CH_(3)CN溶液中的吸收光谱,与它们气相情况的结果相比,溶剂极性的影响使得电子吸收谱发生蓝移.计算结果表明Horst Kunkely和Arnd Vogler所得光谱中既含有单体的特征光谱,又含有二聚体的特征光谱,证明实验溶液中同时存在乙酰丙酮铱的低聚物,并且二者的组分比能被合理推算.最后,对多聚体的形成机理作了简单讨论.

关键词： Ir(acac)_(3) 密度泛函理论(DFT) CIS 电子吸收光谱溶液效应

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基于模糊综合评价的生态服务评估

化工设计通讯 2019年第7期45卷 248-252页

作者：贾晨阳陈玟汐郭闯韦玲最陈秋婷黑龙江科技大学

给出了一个以中国广西作为评估目标的生态系统服务模型,并用模糊综合评价的方法,对不同规模的土地使用项目进行成本效益分析,将生态系统服务纳入项目的成本效益,对项目进行了真实和全面的评估,并得出土地利用项目的成本效益随着项目的... 详细信息

给出了一个以中国广西作为评估目标的生态系统服务模型,并用模糊综合评价的方法,对不同规模的土地使用项目进行成本效益分析,将生态系统服务纳入项目的成本效益,对项目进行了真实和全面的评估,并得出土地利用项目的成本效益随着项目的增大而增大的结论。

关键词：生态服务评估指标体系模糊综合评价环境退化

发酵菜籽粕对生长猪生长性能、机体抗氧化及免疫功能的影响

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西南农业学报 2017年第7期30卷 1662-1666页

作者：邓卉屈东邹成义余丹杨加豹陈瑾汪林书四川省畜牧科学研究院饲料研究所四川成都610066 动物遗传育种四川省重点实验室四川成都610066

【目的】本试验旨在研究发酵菜籽粕对生长猪生长性能、机体抗氧化和免疫功能的影响。【方法】选用健康、体重相近的杜×长×大三元杂交生长猪64头,随机分成4组,每组4个重复,每重复4头猪。对照组饲喂玉米-豆粕型基础日粮,试验1、2、3组... 详细信息

【目的】本试验旨在研究发酵菜籽粕对生长猪生长性能、机体抗氧化和免疫功能的影响。【方法】选用健康、体重相近的杜×长×大三元杂交生长猪64头,随机分成4组,每组4个重复,每重复4头猪。对照组饲喂玉米-豆粕型基础日粮,试验1、2、3组分别饲喂在基础日粮中添加发酵菜籽粕等氮替代2.5%、5%、7.5%豆粕的试验日粮。预试期7 d,正试期31 d。【结果】(1)试验各组平均日增重(ADG)和平均日采食量(ADFI)均高于对照组,试验3组ADG、ADFI和试验2组ADFI均显著高于对照组(P0.05),试验3组F/G最低,较对照组低6.07%(P>0.05)。(2)试验3组血清超氧化物歧化酶(SOD)活性和总抗氧化能力(T-AOC)含量显著高于对照组(P0.05)。(3)试验3组血清免疫球蛋白A(Ig A)、免疫球蛋白G(Ig G)和白细胞介素2(IL-2)含量显著高于对照组(P0.05)。【结论】综上所述,在本试验条件下,发酵菜籽粕可提高生长猪生长性能,改善机体的抗氧化与免疫功能,且等氮替代7.5%豆粕效果显著。

关键词：生长猪发酵菜籽粕生长性能抗氧化免疫

Towards efficient generative AI and beyond-AI computing:New trends on ISSCC 2024 machine learning accelerators

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Journal of Semiconductors 2024年第4期45卷 12-15页

作者： Bohan yang jia chen Fengbin Tu Department of Electronic and Computer Engineering The Hong Kong University of Science and TechnologyHong KongChina AI Chip Center for Emerging Smart Systems The Hong Kong University of Science and TechnologyHong KongChina School of the Gifted Young University of Science and Technology of ChinaHefei 230026Chin

Compared to the last decade when the convolution neu-ral network(CNN)dominated the research field,machine learn-ing(ML)algorithms have reached a pivotal moment called the generative artificial intelligence(AI)*** the emer-gence of large-scale foundation models[1],such as large multi-modal model(LMM)GPT-4[2]and text-to-image generative model DALL·E[3].

关键词： ISSCC beyond AI

Nomogram for overall survival in ampullary adenocarcinoma using the surveillance,epidemiology,and end results database and external validation

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World Journal of Clinical Oncology 2025年第2期16卷 36-51页

作者： jia yang Zi-Yi Wang Jing chen Yao Zhang Lei chen Department of Gastroenterology The First Affiliated Hospital of Army Medical UniversityChongqing 400038China Department of Epidemiology College of Preventive MedicineArmy Medical UniversityChongqing 400038China

BACKGROUND Ampullary adenocarcinoma is a rare malignant tumor of the gastrointestinal ***,only a few cases have been reported,resulting in limited information on *** To develop a dynamic nomogram using internal and external validation to predict survival in patients with ampullary *** Data were sourced from the surveillance,epidemiology,and end results stat *** patients in the database were randomized in a 7:3 ratio into training and validation *** Cox regression univariate and multivariate analyses in the training group,we identified independent risk factors for overall survival and cancer-specific survival to develop the *** nomogram was validated with a cohort of patients from the First Affiliated Hospital of the Army Medical *** For overall and cancer-specific survival,12(sex,age,race,lymph node ratio,tumor size,chemotherapy,surgical modality,T stage,tumor differentiation,brain metastasis,lung metastasis,and extension)and 6(age;surveillance,epidemiology,and end results stage;lymph node ratio;chemotherapy;surgical modality;and tumor differentiation)independent risk factors,respectively,were incorporated into the *** area under the curve values at 1,3,and 5 years,respectively,were 0.807,0.842,and 0.826 for overall survival and 0.816,0.835,and 0.841 for cancer-specific *** internal and external validation cohorts indicated good consistency of the *** The dynamic nomogram offers robust predictive efficacy for the overall and cancer-specific survival of ampullary adenocarcinoma.

关键词： Ampullary adenocarcinoma Dynamic nomogram Gastrointestinal tract Surveillance Epidemiology End results database Survival rate

Contact-impact formulation for multi-body systems using component mode synthesis

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Acta Mechanica Sinica 2013年第3期29卷 437-442页

作者： Peng chen Jin-yang Liu jia-Zhen Hong Department of Engineering Mechanics School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University

The efficiency and accuracy are two most concerned issues in the modeling and simulation of multi-body systems involving contact and impact. This paper proposed a formulation based on the component mode synthesis method for planar contact problems of flexible multi-body systems. A flexible body is divided into two parts： a contact zone and an un-contact zone. For the un-contact zone, by using the fixed-interface substructure method as reference, a few low-order modal coordinates are used to replace the nodal coordinates of the nodes, and meanwhile, the nodal coordinates of the local impact region are kept unchanged, therefore the total degrees of freedom （DOFs） are greatly cut down and the computational cost of the simulation is significantly reduced. By using additional constraint method, the impact constraint equations and kinematic constraint equations are derived, and the Lagrange equations of the first kind of flexible multi-body system are obtained. The impact of an elastic beam with a fixed half disk is simulated to verify the efficiency and accuracy of this method.

关键词： Contact-impact analysis · Flexible multi-body system · Component mode synthesis

An efficient formulation based on the Lagrangian method for contact–impact analysis of flexible multi-body system

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Acta Mechanica Sinica 2016年第2期32卷 326-334页

作者： Peng chen Jin-yang Liu jia-Zhen Hong Department of Engineering Mechanics School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiaotong University

In this paper,an efficien formulation based on the Lagrangian method is presented to investigate the contact–impact problems of f exible multi-body ***,the penalty method and the Hertz contact law are the most commonly used methods in engineering ***,these methods are highly dependent on various non-physical parameters,which have great effects on the simulation ***,a tremendous number of degrees of freedom in the contact–impact problems will influenc thenumericalefficien *** of these two problems,a formulation combining the component mode synthesis method and the Lagrangian method is presented to investigate the contact–impact problems in fl xible multi-body system ***,the finit element meshing laws of the contact bodies will be studied preliminarily.A numerical example with experimental verificatio will certify the reliability of the presented formulationincontact–***,aseries of numerical investigations explain how great the influenc of the finit element meshing has on the simulation *** the limitations of the element size in different regions are summarized to satisfy both the accuracy and efficien y.

关键词： Multi-body dynamics Contact–impact analysis Lagrangian method Component mode synthesis

0.1%溴芬酸钠滴眼液在中低度近视准分子激光上皮下角膜磨镶术后部分替代激素的作用研究

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中国眼耳鼻喉科杂志 2017年第4期17卷 256-260,264页

作者：黄佳沈阳陈敏洁周行涛复旦大学附属眼耳鼻喉科医院眼科卫生部近视眼重点实验室上海200031

目的观察非甾体类抗炎药0.1%溴芬酸钠滴眼液在中低度近视准分子激光上皮下角膜磨镶术(LASEK)后部分替代激素应用的临床疗效观察及对角膜生物力学的影响。方法本研究为前瞻性、随机对照队列临床研究,所有患者完善LASEK术前评估后顺利完... 详细信息

目的观察非甾体类抗炎药0.1%溴芬酸钠滴眼液在中低度近视准分子激光上皮下角膜磨镶术(LASEK)后部分替代激素应用的临床疗效观察及对角膜生物力学的影响。方法本研究为前瞻性、随机对照队列临床研究,所有患者完善LASEK术前评估后顺利完成手术,随访至术后6个月。试验组58例,对照组60例,2组术前屈光度、眼压、角膜厚度无差异,等效球镜度数均低于-6 DS。术后1个月内均使用氟米龙滴眼液,试验组术后1个月后改用溴芬酸钠滴眼液,对照组全程使用氟米龙滴眼液,逐渐减量至停药。在术后1、2、3、6个月观察角膜上皮下雾状混浊(haze)、视力、屈光度、眼压和角膜生物力学参数。结果角膜Haze试验组出现4例,发现后改用氟米龙,对照组出现1例,增加氟米龙用量,直至5例患者Haze逐渐消退,角膜均恢复透明。2组视力和屈光度在术后1、2、3、6个月差异无统计意义。2组术前,术后1、3个月及6个月非接触式眼压计测量的眼压差异均无统计学意义;而在术后2个月时试验组低于对照组约2 mm Hg(1 mm Hg=0.133 k Pa),且差异具有统计学意义(t=-2.486,P=0.016)。角膜补偿眼压(IOPcc)结果显示,2组术前,术后1、6个月IOPcc差异无统计学意义;而在术后2、3个月试验组低于对照组(分别为3 mm Hg和2 mm Hg),且差异具有统计学意义(t=-3.155,P=0.003;t=-2.409,P=0.02)。2组术后各时间点的角膜滞后量(CH)和角膜阻力因子(CRF)均低于术前,而2组间差异在各时间点均无统计学意义。此外,2组眼部充血及术后主观症状差异无统计学意义;且均无特殊不良反应。结论中低度近视眼LASEK术后与常规使用氟米龙相比,术后1个月后采用溴芬酸钠滴眼液替代氟米龙,主观感觉、视力、屈光度及角膜生物力学稳定性一致,眼压的波动更小,角膜Haze的发生率略高。

关键词：准分子激光上皮下角膜磨镶术溴芬酸钠非甾体类抗炎药糖皮质激素角膜生物力学

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： jiaye Li Shuang Pan Yihuang chen Qiong Liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization