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城市垃圾填埋场生态修复后鸟类多样性变化研究

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环境生态学 2024年第2期6卷 71-76页

作者：张国月雷凯茜樊雅东安玫邓树庆杨栋陈修家长江文明馆(武汉自然博物馆) 湖北武汉430000 长江文明馆经营管理有限公司湖北武汉430000 武汉大学图书馆湖北武汉430000

武汉园博园是对城市垃圾填埋场进行生态修复的一个成功案例。为了检验生态修复成效,对后续生态修复工程改造提升和生物多样性保护提供参考,本研究开展了以鸟类为代表的生物多样性本底调查。从2020年1月至2023年6月,持续进行了3年多的鸟... 详细信息

武汉园博园是对城市垃圾填埋场进行生态修复的一个成功案例。为了检验生态修复成效,对后续生态修复工程改造提升和生物多样性保护提供参考,本研究开展了以鸟类为代表的生物多样性本底调查。从2020年1月至2023年6月,持续进行了3年多的鸟类动态监测。武汉园博园鸟种数量从修复前的26种,增加至73种。其中,雀形目鸟类种数最多,占69.9%;繁殖鸟占48%,越冬鸟占43%,过路鸟占9%;肉食性鸟占鸟种总数的60.3%,杂食性鸟占27.4%,植食性鸟占12.3%。鸟类多样性指数、均匀度指数、丰富度指数均呈波动性上升趋势,2020年的香农-维纳指数为1.76,2023年为2.59。武汉园博园生态系统得到明显恢复,但仍有提升空间,需要增加禾本科、豆科植物的种类和数量。

关键词：武汉园博园垃圾填埋场生态修复鸟类多样性生态评价

Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： Yong-Zhi Lin Lu-Kun Feng ya-dong Li Chao-fan Chang Cai-Zhen Zhu Ming-Liang Wang Jian Xu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of *** approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric *** validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric ***,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and *** resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in *** findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT

Laryngopharyngeal reflux disease:Updated examination of mechanisms,pathophysiology,treatment,and association with gastroesophageal reflux disease

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World Journal of Gastroenterology 2024年第16期30卷 2209-2219页

作者： Na Cui Ting Dai yang Liu ya-Yu Wang Jia-Yu Lin Qing-fan Zheng dong-dong Zhu Xue-Wei Zhu Department of Otorhinolaryngology Head and Neck Surgery China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina Department of Ultrasound China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina Department of Gastroenterology China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina

Laryngopharyngeal reflux disease(LPRD)is an inflammatory condition in the laryngopharynx and upper aerodigestive tract mucosa caused by reflux of stomach contents beyond the *** commonly presents with symptoms such as hoarseness,cough,sore throat,a feeling of throat obstruction,excessive throat *** complex condition is thought to involve both reflux and reflex mechanisms,but a clear understanding of its molecular mechanisms is still ***,there is no standardized diagnosis or treatment *** strategies for LPRD mainly include lifestyle modifications,proton pump inhibitors and endoscopic *** paper seeks to provide a comprehensive overview of the existing literature regarding the mechanisms,pathophysiology and treatment of *** also provide an in-depth exploration of the association between LPRD and gastroesophageal reflux disease.

关键词： Laryngopharyngeal reflux Gastroesophageal reflux Head neck surgery Laryngitis Otolaryngology

Fabricating functionally graded Fe-Cr-Co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel Research International 2024年第3期31卷 729-737页

作者： ya-zhou He ya-qing Hou Peng Shen Hao Zhang dong Zhou Hang Su Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Material Digital R&D Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and *** graded Fe-Cr-Co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and Co *** effects of different Fe,Cr and Co contents on the microstructure,magnetic properties and hardness of Fe-Cr-Co alloys prepared by LPBF were *** as-built Fe-Cr-Co alloys present a single body-centered-cubic phase and have a homogeneous distribution of *** mechanical properties and magnetic properties of the compositionally graded sample show a gradient *** the increase in Cr content,the Vickers hardness of the sample increases,and the saturation magnetization of the sample *** optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder *** in-situ alloying technology has the potential to further explore Fe-Cr-Co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-Co alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property

Weighted Composition Operators That Preserve Frames On Weighted Hardy Spaces

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1645-1654页

作者： ya Li dong Rui Liu Guo Xiang Lu School of Mathematical Sciences and LPMC Nankai UniversityTianjin300071P.R.China School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan430073P.R.China

In this paper, we characterize weighted composition operators that preserve frames on the weighted Hardy spaces in the unit disk. In particular, we obtain the symbol properties of the bounded invertible weighted composition operators. Moreover, we establish the equivalence between bounded invertible operators and frame-preserving operators. Furthermore, we show that weighted composition operator preserves frames if and only if it preserves the Riesz bases property. Additionally,we investigate the weighted composition operators that preserve tight or normalized tight frames on the Dirichlet space.

关键词： Weighted composition operators Weighted Hardy spaces frames invertible

Nuclearity and Finite-Representability in the System of Completely Integral Mapping Spaces

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1197-1214页

作者： Zhe dong Ji Cheng TAO ya Fei ZHAO Department of Mathematics Zhejiang UniversityHangzhou 310027P.R.China Department of Mathematics China Jiliang UniversityHangzhou 310018P.R.China Department of Mathematics Zhejiang International Studies UniversityHangzhou 310023P.R.China

In this paper,we investigate local properties in the system of completely integral mapping *** introduce notions of injectivity,local reflexivity,exactness,nuclearity,finite-represent ability and WEP in the system of completely integral mapping *** we obtain that any finite-dimensional operator space is injective in the system of completely integral mapping *** we prove that C is the unique nuclear operator space and the unique exact operator space in this *** also show that C is the unique operator space which is finitely representable in{T_(n)}n∈Nin this *** corollaries,Kirchberg’s conjecture and QWEP conjecture in the system of completely integral mapping spaces are false.

关键词： Completely integral mapping space injectivity exactness nuclearity finite-representability WEP

Numerical study on the effective thermal conductivity and thermal tortuosity of porous media with different morphologies

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Science China(Technological Sciences) 2024年第6期67卷 1685-1694页

作者： DU Shen LI dong LI Meng-Jie HE ya-Ling Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China

Effective thermal conductivity and thermal tortuosity are crucial parameters for evaluating the effectiveness of heat conduction within porous *** direct pore-scale numerical simulation method is applied to investigate the heat conduction processes inside porous structures with different *** thermal conduction performances of idealized porous structures are directly compared with real foams across a wide range of *** foam structures are reconstructed using X-ray computed tomography and image processing techniques,while Kelvin and Weaire-Phelan structures are generated through periodic unit cell *** detailed temperature fields inside the porous structures are determined by solving the heat conduction equation at the pore *** results present that the equivalent thermal conductivity of Kelvin and Weaire-Phelan structures is similar to and greater than that of the real foam structure with the same strut *** thermal tortuosity of real foam structure is relatively larger and the heat conduction path becomes straighter by adopting the anisotropic *** thermal tortuosity of the fluid channels for Kelvin,Weaire-Phelan,and real foam structures is close to *** thermal conductivity of porous structures with heat transfer fluid increases as the thermal conductivity ratio of fluid to solid becomes larger.A small porosity of porous media leads to a larger equivalent thermal conductivity due to the dominant contribution of porous skeleton in the heat conduction *** derived from parallel and series models,as well as the Maxwell-Eucken models,provide decent predictions of effective thermal conductivity,with an average error of less than 8%in the entire range of thermal conductivity ratio.

关键词： volumetric solar receiver porous morphology direct pore-scale simulation equivalent thermal conductivity thermal tortuosity empirical correlation

Traditional Chinese medicine:an important broad-spectrum anti-coronavirus treatment strategy on COVID-19 background?

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Traditional Medicine Research 2022年第3期7卷 1-18页

作者： Run-dong Chai ya-dong fan Qi-yao Li Huan-Tian Cui Hai-Zhao Liu Ying Wang Bo-yang Gong Lu Han Shuai Zhang Yu-Hong Bian Jun Kang Yu Wang Tianjin University of Traditional Chinese Medicine Tianjin 300193China School of life Sciences Shandong UniversityQingdao 266071China School of life Sciences Tianjin UniversityTianjin 300072China

Coronaviruses exist widely in nature,can cause cross-species transmission,and pose serious threats to human and animal *** the past 20 years,coronaviruses have led to three major epidemics that have caused global panic,including severe acute respiratory syndrome,Middle East respiratory syndrome,and coronavirus *** present,coronavirus disease 19 not only spreads rapidly,but also mutates easily to escape host immune response,becoming more *** present,there are no effective specific therapeutic drugs or *** targeting severe acute respiratory syndrome coronavirus 2 and the host cell defense system that have been developed based on the structure and replication cycle of coronaviruses have a certain broad-spectrum antiviral effect;however,their efficacy still needs to be demonstrated in further clinical *** Chinese medicine has an indispensable role in the ongoing response to coronavirus ***-virus treatment with traditional Chinese medicine has advantages such as broad-spectrum application,low toxicity and side effects,low susceptibility to drug resistance,and overall comprehensive ***,researches on effective components and mechanisms of action of the anti-viral effects of traditional Chinese medicine have increasingly gained *** present paper examines coronaviruses,specifically summarizing the genomes,replication mechanisms,and mutant ***,the therapeutic effects and mechanisms of action of modern broad-spectrum anti-coronavirus drugs and traditional Chinese medicine are *** considering the virus and the targets in the host comprehensively,in addition to the beneficial multi-target and multi-path antiviral effects of traditional Chinese medicines,this paper could guide the development of treatment strategies for broad-spectrum anti-coronavirus traditional Chinese medicines,and could facilitate the modernization and globalization of traditional Chinese medic

关键词： COVID-19 SARS-CoV-2 traditional Chinese medicine broad-spectrum antivirals

Local search yields a PTAS for fixed-dimensional k-means problem with penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 351-362页

作者： fan Yuan Da-Chuan Xu dong-Lei Du dong-Mei Zhang Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing 100124China Faculty of Management University of New BrunswickFrederictonNB E3B 9Y2Canada School of Computer Science and Technology Shandong Jianzhu UniversityJinan 250101ShandongChina

We study a problem called the k-means problem with penalties(k-MPWP),which is a natural generalization of the typical k-means *** this problem,we have a set D of client points in R^(d),a set F of possible centers in R^(d),and a penalty cost Pj>O for each point j∈*** are also given an integer k which is the size of the center point *** want to find a center point set S■F with size k,choose a penalized subset of clients P■D,and assign every client in D\P to its open *** goal is to minimize the sum of the squared distances between every point in D\P to its assigned centre point and the sum of the penalty costs for all clients in *** using the multi-swap local search technique and under the fixed-dimensional Euclidean space setting,we present a polynomial-time approximation scheme(PTAS)for the k-MPWP.

关键词： Approximation algorithm k-means Local search Penalty