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Numerical simulation of the sedimentation of cylindrical pollutant particles in fluid

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Journal of Environmental Sciences 2002年第4期14卷 433-438页

作者： LINJian-zhong WANGYe-long wangwei-xiong YUZhao-sheng DepartmentofMechanics ZhejiangUniversityHangzhou310027China DepartmentofMechanicalandMechatronicEngineering theUniversityofSydneyNSW2006Australia

The sedimentation of cylindrical pollutant particles which fall through a fluid is investigated. Differing from previous research work, particle oscillation and effect of particle on the fluid are considered, and the torque exerted on a particle when viscous fluid flow around a particle is got through experiment and included in the numerical simulation. The computational results showed that the sedimentation velocities of particle increase slowly with the increase of particle aspect ratio . For disk like particle, when the motion direction of particle is parallel to axis of particle, particle falls more slowly than the case of perpendicular to axis of particle; while for rod like particle, it is inverse. For sedimentation of a crowd of high frequency oscillating cylindrical particles with arbitrary initial orientation, both vertical velocity and horizontal velocity oscillate dramatically, the degree of oscillation of the former is stronger than the later. A crowd of particles fall more quickly than an isolated particle. Particles tend to strongly align in the direction of gravity. The computational results agreed well with the experimental ones and helpful for controlling of pollutant particles.

关键词： cylindrical pollutant particles sedimentation orientation velocity numerical simulation

生成式人工智能服务的版权侵权风险与化解路径

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安庆师范大学学报（社会科学版） 2024年第4期43卷 65-71页

作者：崔汪卫苏晓红安庆师范大学法学院安徽安庆246133

数据和算法是生成式人工智能服务的核心要素,生成内容质量水平与数据的规模与质量密切相关。高质量的数据往往涉及著作权的保护,由于著作权保护以及市场主体的逐利性,服务提供者往往通过数据抓取的方式获取数据进行训练,对于训练数据的... 详细信息

数据和算法是生成式人工智能服务的核心要素,生成内容质量水平与数据的规模与质量密切相关。高质量的数据往往涉及著作权的保护,由于著作权保护以及市场主体的逐利性,服务提供者往往通过数据抓取的方式获取数据进行训练,对于训练数据的版权侵权往往反映在生成内容中,损害著作权人合法权益,不利于行业健康发展。鉴于生成式人工智能服务提供者在数据输入以及算法设计上的较强控制力,应明确生成式人工智能存在的版权风险,理清以ChatGPT为代表的生成式人工智能服务版权侵权风险动因,从服务提供主体和法律制度调整两个层面构建受版权保护数据有序使用架构,鼓励创新,促进数字内容产业健康发展。

关键词：生成式人工智能版权风险合理使用服务提供者

上皮源性细胞因子及其靶向抗体在哮喘中的研究进展

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微生物学免疫学进展 2024年第2期52卷 86-93页

作者：李佳颖(综述) 王炜(审校) 陈彦(审校) 首都医科大学基础医学院免疫学系北京100069

哮喘(asthma)是以慢性气道炎症、气道高反应性、气道重塑和可逆性气流受限为基本特征的慢性呼吸系统疾病之一。研究表明,上皮源性细胞因子中的白细胞介素(interleukin, IL)-33、IL-25和胸腺基质淋巴细胞生成素(thymic stromal lymphopoi... 详细信息

哮喘(asthma)是以慢性气道炎症、气道高反应性、气道重塑和可逆性气流受限为基本特征的慢性呼吸系统疾病之一。研究表明,上皮源性细胞因子中的白细胞介素(interleukin, IL)-33、IL-25和胸腺基质淋巴细胞生成素(thymic stromal lymphopoietin, TSLP)在哮喘的发生、发展中起到重要作用。目前,针对上皮源性细胞因子研发的单克隆抗体药物已成为治疗哮喘的新型靶点。现就IL-33、IL-25和TSLP的作用机制及针对这3种细胞因子的靶向单克隆抗体在哮喘治疗中的研究作一概述。

关键词：哮喘胸腺基质淋巴细胞生成素白细胞介素-33 白细胞介素-25

Dynamically Photocrosslinking of Polypropylene/EPDM Blends as a Thermoplastic Elastomer

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Chemical Research in Chinese Universities 2004年第1期20卷 111-113页

作者： wangwei-zhi WUQiang-hua QUBao-jun DepartmentofPolymerScienceandEngineering UniversityofScienceandTechnologyofChinaHefei230026P.R.China

The mechanical properties and the crystal morphological structures of the dynamically photocrosslinked polypropylene(PP)/ethylene-propylene-diene terpolymer(EPDM) blends have been studied by means of mechanical tests, wide-angle X-ray diffraction(WAXD), and differential scanning calorimetry(DSC). The dynamically photocrosslinking of the PP/EPDM blends can improve the mechanical properties considerably, especially the notched Izod impact strength at low temperatures. The data obtained from the mechanical tests show that the notched Izod impact strength of the dynamically photocrosslinked sample with 30% EPDM at -20 ℃ is about six times that of the uncrosslinked sample with the same EPDM component. The results from the gel content, the results of WAXD, and the DSC measurements reveal the enhanced mechanism of the impact strength for the dynamically photocrosslinked PP/EPDM blends as follows: (1) There exists the crosslinking of the EPDM phase in the photocrosslinked PP/EPDM blends; (2) The β-type crystal structure of PP is formed and the content of α-type crystal decreases with increasing the EPDM component; (3) The graft copolymer of PP-g-EPDM is formed at the interface between the PP and EPDM components. All the above changes of the crystal morphological structures are favorable for increasing the compatibility and enhancing the toughness of the PP/EPDM blends at low temperatures.

关键词： Polypropylene Ethylene-propylene-diene terpolymer Dynamical Photocrosslinking Structure and properties

Near Resonant Electronic and Rotational Energy Transfer AB（^1∏, J）＋C（^slj）→AB（^1∏, J＇）＋C（^sl j＇）

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Communications in Theoretical Physics 2005年第5期43卷 879-885页

作者： wangwei-Li SONGPeng SHENYang MAFeng-Cai DepartmentofPhysics LiaoningUniversityShenyang110036China

In our previous theoretical study, the theoretical model of thecollision-induced electronic and rotational energy transfer of AB(~1Σ, J) + C(~sl_j) → AB(~1Σ,J′) + C(~sl_(j′)) was presented. To further study the collision-induced electronic and rotationalenergy transfer theoretically on AB( ~1Π, J) + C(~sl_j) → AB( ~1Π, J′) + C(~sl_(j′)), atheoretical model is presented, based on the time-dependent first-order Born approximation, takinginto account the anisotropic Lennard-Jones interaction potential and 'straight-line' trajectoryapproximation. The changing tendency of the transitional probabilities with the anisotropicparameter is discussed.

关键词： quantum interference rotational energy transfer near resonant electronic

2002-2021年浙江省宁波市老年痴呆死亡趋势分析

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中国慢性病预防与控制 2024年第4期32卷 277-281页

作者：孙家盛陈翔应佳颖楼望伟王永宁海县疾病预防控制中心慢性病与健康教育科浙江省宁波315600 宁波市疾病预防控制中心慢性非传染性疾病防制所浙江省宁波315010

目的了解2002—2021年宁波市老年痴呆的死亡情况及其影响因素,为制定老年痴呆的防控策略提供科学依据。方法收集2002—2021年宁波市所有根本死因为老年痴呆的死亡病例数据和同期户籍人口数据,采用SPSS 20.0计算老年痴呆的粗死亡率、中... 详细信息

目的了解2002—2021年宁波市老年痴呆的死亡情况及其影响因素,为制定老年痴呆的防控策略提供科学依据。方法收集2002—2021年宁波市所有根本死因为老年痴呆的死亡病例数据和同期户籍人口数据,采用SPSS 20.0计算老年痴呆的粗死亡率、中国人口标化率(中标率)和世界人口标化率(世标率)。利用Joinpoint 4.***.1.0软件计算平均年度变化百分比(AAPC),分析老年痴呆死亡率变化趋势。采用差别分解法计算人口结构老化和非人口学因素改变对死亡率的增加值和贡献率。结果2002—2021年,宁波市根本死因为老年痴呆的死亡病例为8617例,粗死亡率为38.43/10万,中标率为33.44/10万,世标率为44.25/10万,粗死亡率、世标率呈下降趋势,AAPC值分别为-1.08%、-1.48%(P0.05);城市中标率呈下降趋势,AAPC值为-3.33%(P<0.05)。老年痴呆的城市中标率(28.90/10万)低于农村(36.42/10万),差异有统计学意义(χ^(2)=89.826,P<0.05)。2002—2021年,70~<80岁组的老年痴呆粗死亡率呈下降趋势,AAPC值为-3.29%(P<0.05)。总人群的2021年老年痴呆粗死亡率与2002年的差别为2.19/10万。人口老龄化对死亡率的增加值为6.59/10万,贡献率为300.65%;非人口学因素改变对死亡率的增加值为-4.40/10万,贡献率为-200.65%。结论人口结构老化可能引起老年痴呆死亡率升高,其他非人口学因素改变可能会导致死亡率下降。宁波市老年痴呆死亡率呈现逐年下降趋势,应积极探索女性、农村和高年龄组老年痴呆患者的防治策略,采取针对性的手段以提高患者的生存质量和降低死亡率。

关键词：老年痴呆死亡率平均年度变化百分比差别分解法

Enhanced Nonlinear Optical Properties of Laser Deposited Ag／BaTiO3 Nanocomposite Films

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Chinese Physics Letters 2003年第6期20卷 924-927页

作者： YANGGuang wangwei-Tian YANGGuo-Zhen CHENZheng-Hao LaboratoryofOpticalPhysics InstituteofPhysicsandCenterforCondensedMatterPhysicsChineseAcademyofSciencesBeijing100080

The composite films containing Ag particles embedded in BaTiO3 matrix were deposited on MgO (100) substrates by using the pulsed laser deposition technique and characterized by x-ray diffraction and x-ray photoelectron spectroscopy. The absorption peak resulting from the surface plasmon resonance of Ag particles is found at the wavelength of 430 nm. The third-order nonlinear optical characteristics of the films are determined by z-scan technique using a nanosecond laser. The results show that the Ag/BaTiO3 nanocomposite films exhibit great optical nonlinearities and the real and imaginary parts of the third-order nonlinear susceptibility X(3) are calculated to be 4.544 x 10-6 esu and 2.352 x 10-7 esu, respectively. The enhancement mechanism of X(3) is discussed.

关键词： Nanocomposite films

Emission control for precursors causing acid rain(V): Improvement of acid soil with the bio-briquette combustion ash

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Journal of Environmental Sciences 2004年第5期16卷 705-711页

作者： DONGXu-hui SAKAMOTOKazuhiko wangwei GAOShi-dong ISOBEYugo Sino-JapaneseFriendshipCenterforEnvironmentalProtection Beijing100029China GraduateSchoolofScience＆Engineering SaitamaUniversity255Shimo-ohkuboUrawaSaitama338-8570Japan InstituteforEnvironmentalStudiesofChina ChongqingEnvironmentalProtectionBureau China

The bio-briquette technique which mixes coal, biomass and sulfur fixation agent and bio-briquettes under 3—5 t/cm 2 line pressure has aroused people's attention in view of controlling the air pollution and the acid rain. In this paper, the physicochemical properties of bio-briquette and its ash were investigated. And the acid soil was improved by the bio-briquette combustion ash, which contained nutritive substances such as P, N, K and had the acid-neutralizing capacity(ANC). The pH, EC, effective nutrient elements(Ca, Mg, K, P and N), heavy metal elements(Al, Cu, Cd, Cr, Zn and Mn) and acid-neutralizing capacity change of ash-added soils within the range of 0—10%, were also studied. Specially, when 5% bio-briquette combustion ash was added to the tested soil, the content of the effective elements such as Ca, Mg and K rose by 100 times, 7 times and twice, respectively. The total nitrogen also increased by about twice. The results showed the oxyanions such as that of Al, Cu, Cd, Cr, Zn and Mn were not potentially dangerous, because they were about the same as the averages of them in Chinese soil. It is shown that the ANC became stronger, though the ANC hardly increases in the ash-added soil. On the basis of the evaluation indices, it is concluded that the best mixture ratio is to add 2.5%—8% of the bio-briquette combustion ash to the tested soil.

关键词： bio-briquette combustion ash soil improvement ANC heavy metal element nutrient element

Review of Distribution Network Phase Unbalance: Scale, Causes, Consequences, Solutions, and Future Research Directions

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CSEE Journal of Power and Energy Systems 2020年第3期6卷 479-488页

作者： Kang Ma Lurui Fang wangwei Kong University of Bath BathBA27AYUK

Phase unbalance is widespread in the distribution networks in the UK,continental Europe,US,China,and other countries and *** paper first reviews the mass scale of phase unbalance and its causes and *** challenges arise from phase rebalancing:the scalability,data scarcity,and adaptability(towards changing unbalance over time).Solutions to address the challenges are:1)using retrofit table,maintenance-free,automatic solutions to overcome the scalability challenge;2)using data analytics to overcome the data-scarcity challenge;and 3)using phase balancers or other online phase rebalancing solutions to overcome the adaptability *** paper categorizes existing phase rebalancing solutions into three classes:1)load/lateral re-phasing;2)using phase balancers;3)controlling energy storage,electric vehicles,distributed generation,and micro-grids for phase *** advantages and limitations are analyzed and ways to overcome their limitations are ***,this paper suggests future research topics:1)long-term forecast of phase unbalance;2)the whole-system analysis of the unbalance-induced costs;3)the phase unbalance diagnosis for data-scarce LV networks;4)techno-commercial solutions to exploit the flexibility from large three-phase customers for phase balancing;5)the optimal placement of phase balancers;6)the transition from single-phase customers to three-phase customers.

关键词： Low voltage power distribution phase unbalance phase balancing three-phase system