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中国城市碳排放强度的时空演变、动态跃迁及收敛趋势

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环境科学 2024年第4期45卷 1869-1878页

作者：杨清可王磊朱高立李颖范业婷王雅竹南京财经大学公共管理学院南京210023 中国科学院南京地理与湖泊研究所南京210008

合理控制城市碳排放强度对于中国实现碳达峰、碳中和目标愿景以及应对气候变化的意义重大.采用夜间灯光数据反演得到2001~2020年城市碳排放量,测算碳排放强度,并对城市碳排放强度的时空演变、动态跃迁及收敛趋势进行研究.结果表明:(1)... 详细信息

合理控制城市碳排放强度对于中国实现碳达峰、碳中和目标愿景以及应对气候变化的意义重大.采用夜间灯光数据反演得到2001~2020年城市碳排放量,测算碳排放强度,并对城市碳排放强度的时空演变、动态跃迁及收敛趋势进行研究.结果表明:(1)中国城市碳排放强度持续下降,从2001年的2.79 t·万元^(-1)降至2020年的0.88 t·万元^(-1),年均降幅5.94%.各大区域城市碳排放强度的差距存在收敛特征.空间分布上,城市碳排放强度的高值区集中在东北地区,以及内蒙古、宁夏和陕西等地,南北地区差异拉大,中南部与东部地区的碳排放强度降幅明显,高低集聚层次分明.(2)中国城市碳排放强度的global Moran's I较高,均值为0.436,空间自相关性显著.碳排放强度以城市自身与邻域城市均未发生跃迁的类型为主,不同类型间时空跃迁的概率较低,凝聚度指数高达82.57%.跃迁类型的稳态较高,碳排放强度的时空演变存在空间锁定效应和“俱乐部趋同”现象.(3)城市碳排放强度的σ收敛不显著,但存在绝对β收敛和条件β收敛.绝对β收敛速度差异明显,全国的收敛速度为3.137%.东部和西部地区的收敛速度略低,分别仅有3.043%和3.050%.(4)条件β收敛速度有所加快.东部地区增幅最大,为3.772%;东北地区的收敛速度提升小,仅有0.098%;中部和西部的收敛速度增长处于中间水平,分别为0.486%和0.661%.人均GDP提升、人口空间集聚和外资引进带来低碳技术的变革、财政资金对R&D的投入倾斜促进了碳排放强度的空间收敛.

关键词：城市碳排放强度时空演变动态跃迁空间收敛

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戏曲俊扮妆容考

戏剧艺术 2024年第3期 178-190,I0004-I0006页

作者：李芽林佳上海戏剧学院舞台美术系上海京剧院

中国戏曲俊扮从古至今的发展与演变历程背后有着相应的审美动因与技术路径。俊扮的功能主要是为了美化角色,进而通过“变形取神”来塑造人物。因此,其早期是通过敷粉、施朱、描黛和贴画面花来进行美化妆扮。随着戏曲的逐渐成熟,又出现... 详细信息

中国戏曲俊扮从古至今的发展与演变历程背后有着相应的审美动因与技术路径。俊扮的功能主要是为了美化角色,进而通过“变形取神”来塑造人物。因此,其早期是通过敷粉、施朱、描黛和贴画面花来进行美化妆扮。随着戏曲的逐渐成熟,又出现了通过“梳水头”、贴片子和面部牵引术的方法来重塑脸型;通过勒头吊眉眼来增强人物精气神;通过戴假髯来塑造生脚人物等技术方式。这些技术方式使得戏曲人物造型在舞台上不仅“打远”,而且美观,并实现了塑造人物的需要,最终形成戏曲舞台俊扮的审美程式。

关键词：戏曲俊扮容妆旦脚生脚

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Coal-based activated carbon prepared by H2O activation process for supercapacitors using response surface optimization method

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Frontiers of Chemical Science and Engineering 2024年第6期18卷 31-40页

作者： Shanxin Xiong Fengyan Lv Chenxu Wang Nana yang Yukun Zhang Qingyong Duan Shuaishuai Bai Xiaoqin Wang Zhen Li Jianwei Xu College of Chemistry and Chemical Engineering Xi’an University of Science and TechnologyXi’an 710054China Key Laboratory of Coal Resources Exploration and Comprehensive Utilization Ministry of Land and ResourcesXi’an 710021China Institute of Sustainability for Chemicals Energy and EnvironmentJurong Island 627833Singapore

The scalable production of high grade activated carbon from abundant coal for supercapacitors application is an efficient way to achieve high value-added utilization of coal ***,this technology is challenging due to lack of comprehensive understanding on the mechanism of activation process and effect of external *** this paper,the effect of activating temperature and time on the specific capacitance of coal-based activated carbon prepared by H2O steam activation was studied using the response surface *** optimal conditions,coal-based activated carbon exhibits the largest specific capacitance of 194.35 F·g^(−1),thanks to the appropriate pore/surface structure and defect *** functional theory calculations explain in detail the mechanism of contraction of aromatic rings and overflow of H2 and CO during the ***,oxygen-containing functional groups are introduced,contributing to the pseudocapacitance property of coal-based activated *** mechanism of reactions between aromatic carbon and H2O vapor provides understanding on the role of water during coal processing at the molecular level,offering great potential to regulate product distribution and predict rate of pore *** insight would contribute to the advancement of other coal processing technology such as gasification.

关键词： response surface optimization coal-based activated carbon supercapacitor activating mechanism

A novel long persistent luminescent material CaGeO_(3):Tb^(3+)with photo-stimulation properties

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Journal of Rare Earths 2024年第7期42卷 1233-1239,I0002页

作者： Wei Meng Xiaoyan Fu Tongyan Lin Zewen Liu Naihui Chen Jiaxu Zhang Runyao Liu Rujun yang Long Chen Hongwu Zhang School of Chemistry and Material Sciences Ludong UniversityYantai264025China College of Materials Science and Engineering Xiamen University of TechnologyXiamen361024China College of Materials Xiamen UniversityXiamen361005China

A novel green long afterglow material CaGeO_(3):Tb^(3+)was synthesized by high temperature solid phase *** to the experimental results,CaGeO_(3):Tb^(3+)is a green long persistent luminescent(LPL)material with excellent ***_(3):Tb^(3+)shows LPL emission peak at 442,490.9,548.7,588.5 and 623.8 nm,corresponding to ^(5)D_(3) to^(7)F_(4)and^(5)D_(4)to^(7)F_(J)(J=6,5,4,3)transitions of Tb^(3+).Its CIE coordinates are(0.27,0.50),indicating that the afterglow emission is close to the light of green *** addition,after the excitation source is turned off,the afterglow time is longer than 90 *** an interval of 7 h,the photo-stimulation luminescence(PSL)can be observed by using 980 nm laser cyclic *** thermoluminescence(ThL)results show that there are three types of traps in the material and their depths are 0.666,0.774 and 0.892 eV respectively,which are caused by the doping of Tb^(3+).All the results show that CaGeO_(3):Tb^(3+)is an excellent long afterglow luminescent material.

关键词： Long persistent luminescence Photo-stimulation Trap CaGeO_(3):Tb^(3+) Rare earths

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Dynamic convergent shock compression initiated by return current in high-intensity laser-solid interactions

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Matter and Radiation at Extremes 2024年第4期9卷 40-53页

作者： Long yang Martin Rehwald Thomas Kluge Alejandro LasoGarcia Toma Toncian Karl Zeil Ulrich Schramm Thomas E.Cowan Lingen Huang Helmholtz-Zentrum Dresden-Rossendorf 01328 DresdenGermany Technische Universitat Dresden 01062 DresdenGermany

We investigate the dynamics of convergent shock compression in solid cylindrical targets irradiated by an ultrafast relativistic laser *** particle-in-cell simulations and coupled hydrodynamic simulations reveal that the compression process is initiated by both magnetic pressure and surface ablation associated with a strong transient surface return current with density of the order of 10^(17) A/m^(2) and lifetime of 100 *** results show that the dominant compression mechanism is governed by the plasma β,i.e.,the ratio of thermal pressure to magnetic *** targets with small radius and low atomic number Z,the magnetic pressure is the dominant shock compression *** to a scaling law,as the target radius and Z increase,the surface ablation pressure becomes the main mechanism generating convergent ***,an indirect experimental indication of shocked hydrogen compression is provided by optical shadowgraphy measurements of the evolution of the plasma expansion *** results presented here provide a novel basis for the generation of extremely high pressures exceeding Gbar(100 TPa)to enable the investigation of high-pressure physics using femtosecond J-level laser pulses,offering an alternative to nanosecond kJ-laser pulse-driven and pulsed power Z-pinch compression methods.

关键词： shock convergent return

Effect of cooling method on TiN precipitation behavior of high-titanium high-strength steel during solidification

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Journal of Iron and Steel Research International 2024年第7期31卷 1692-1703页

作者： Xue-jian Zhang Guang-wei yang Yong Wan Yong-hong Wen Chuan-sheng Tang Ming-qi Liu Li-jie Tian Key Laboratory of Metallurgical Emission Reduction and Resources Recycling Anhui University of TechnologyMa'anshan 243002AnhuiChina School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina Baosteel Central Research Institute Baoshan Iron and Steel Co.Ltd.Shanghai 201999China

Metallographic microscopy,scanning electron microscopy and TiN growth thermodynamic and kinetic equations were used to investigate the morphology,quantity,and size of TiN in the center of high-titanium high-strength steels under different solidification cooling *** results showed that TiN in the center of the experimental steels mainly existed in three forms:single,composite(Al2O3-TiN),and multi-particle *** began precipitating at around 1497℃(solidification fraction of 0.74).From the end of melting to solidification for 180 s,the cooling rates in the center of the experimental steels for furnace cooling,air cooling,refractory mold cooling,and cast iron mold cooling tended to stabilize at 0.17,0.93,1.65,and 2.15℃/s,*** size of TiN in the center of the experimental steel cooled using furnace cooling was mainly concentrated in the 5-15 pm *** contrast,the size of TiN in the center of the experimental steels cooled using air cooling,refractory mold cooling,and cast iron mold cooling were mainly concentrated in the 1-5 pm *** addition,their density of TiN in the center of the experimental steels is signif-icantly higher than that of the furnace-cooled experimental *** and kinetic precipitation models of TiN established predicted the growth size of TiN in a high-titanium high-strength steel when the solidification cooling rates are not below 0.93℃/s.

关键词： High-titanium steel Cooling method TiN Thermodynamics Kinetics

Machine learning in predicting postoperative complications in Crohn’s disease

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2745-2747页

作者： Li-Fan Zhang Liu-Xiang Chen Wen-Juan yang Bing Hu Department of Gastroenterology and Hepatology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Digestive Endoscopy Medical Engineering Research Laboratory West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

Crohn's disease(CD)is a chronic inflammatory bowel disease of unknown origin that can cause significant disability and morbidity with its *** to the unique nature of CD,surgery is often necessary for many patients during their lifetime,and the incidence of postoperative complications is high,which can affect the prognosis of ***,it is essential to identify and manage post-operative *** learning(ML)has become increasingly im-portant in the medical field,and ML-based models can be used to predict post-operative complications of intestinal resection for ***,a valuable article titled“Predicting short-term major postoperative complications in intestinal resection for Crohn's disease:A machine learning-based study”was published by Wang et *** appreciate the authors'creative work,and we are willing to share our views and discuss them with the authors.

关键词： Crohn’s disease Intestinal resection Postoperative complications Machine learning Explainability

Effect of V on high-temperature mechanical properties of Al-5Cu-1.5Ni alloy

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Journal of Iron and Steel Research International 2024年第7期31卷 1792-1810页

作者： Jun-ge Cui Yong-bin Chen Xiang-zhou Fu Hai-long yang Han-zhang Wang An-min Li Li-wen Pan School of Resources Environment and MaterialsGuangxi UniversityNanning 530004GuangxiChina State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures Nanning 530004GuangxiChina Guangxi Higher Education Key Laboratory of Advanced Materials Nanning 530004GuangxiChina

The effects of V on microstructure,room temperature,and high-temperature(350℃)mechanical properties of Al-5Cu-1.5Ni alloy were *** results show that Al-5Cu-1.5Ni-xV alloys mainly compriseα-Al,Al_(2)Cu,Al_(3)(Ni,Cu)_(2),Al_(3)Ni,Al7Cu4Ni,and Al_(10)V *** addition of V can signally refineα-Al dendritic structure,which improves the mechanical properties of the as-cast alloys at room and high *** T6 heat treatment(540℃/12 h/WC+170℃/8 h/AC),α-Al,network skeleton structure Al_(3)(Ni,Cu)_(2),and Al_(10)V phases all show coarsening,while the fine nano-θ'-Al_(2)Cu precipitated from the matrix and dispersed *** introduction of V promotes the quantity of precipitatedθ'-Al_(2)Cu *** ultimate tensile strength of the heat-treated alloys at room and high temperatures is greatly improved compared to that of the as-cast *** highest high-temperature ultimate tensile strength of the alloys with V is 111.8 MPa,21.5%higher than that of the base *** analysis shows that the improvement of high-temperature mechanical properties after heat treatment is mainly due to the introduction of V,increasing the precipitated quantity of nano-θ'-Al_(2)Cu particles and improving its thermal *** dispersion strengthening effect ofθ'-Al_(2)Cu particles exceeds the weakening effect of other adverse microstructures on the mechanical properties.

关键词： Al-Cu-Ni-V alloy θ'-Al_(2)Cu phase Heat treatment Microstructure Mechanical property

融合SVM-LDA与加权相似度的潜在新兴技术识别研究——以人工智能领域为例

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情报学报 2024年第5期43卷 563-574页

作者：冉从敬田文芳武汉大学信息管理学院武汉430072

在新一轮科技革命和产业变革加速发展的大背景下,如何在新技术不断涌现的技术大海中精准找到和识别出有颠覆性潜力的新兴技术,对于国家、企业参与主体和相关商业投资机构把握科技创新发展趋势和方向、合理配置科技资源、提前进行科技战... 详细信息

在新一轮科技革命和产业变革加速发展的大背景下,如何在新技术不断涌现的技术大海中精准找到和识别出有颠覆性潜力的新兴技术,对于国家、企业参与主体和相关商业投资机构把握科技创新发展趋势和方向、合理配置科技资源、提前进行科技战略规划与技术布局具有重要的意义。本文提出一种基于知识增强SVM-LDA(Support Vector Machine-Latent Dirichlet Allocation)的新兴技术主题识别模型。首先,基于专家小组的先验知识,制定基础技术类别划分标准;其次,将技术类别划分标准作为先验知识输入SVM-LDA模型,得到技术主题聚类结果;再其次,基于类别主题词的加权相似度计算,确定潜在新兴关键技术;最后,以人工智能领域为例进行实证研究。采用本文模型共得到24项潜在新兴技术,主要分布在特种机器人技术、监测预警技术、视频图像处理技术、语音识别技术、自动规划和决策技术以及自然语言处理技术6个大类方向。

关键词：新兴技术知识增强 SVM-LDA模型加权相似度人工智能领域

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