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上海第二医科大学学报 1998年第2期18卷 153-155页

作者：方文强 Bartoli JM moulin g 上海第二医科大学附属瑞金医院放射科 200025 法国马赛医科大学拉蒂蒙娜医院放射科

对3例解剖外——动脉旁路移植血管阻塞的患者进行了5次局部溶拴治疗,其中1例同时进行了血管成形术(PTA)和内支架治疗。全组均获阻塞血管再开通,无1例并发症。局部溶栓治疗动脉旁路移植血管阻塞安全有效,并可与 PTA、内支架治疗结合使用。

关键词：血管阻塞动脉旁路移植血管溶栓疗法

Numerical Modeling of Mass Transfer in the Interaction between River Biofilm and a Turbulent Boundary Layer

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Open Journal of Fluid Dynamics 2024年第1期14卷 1-23页

作者： Falilou Coundoul Evrad M. D. Ngom Frédéric Y. moulin Institut Polytechnique de Saint-Louis Université Gaston Berger Saint-Louis Senegal Institut de Mécanique des Fluides de Toulouse UMR 5502-Université de Toulouse Occitanie France

In this article dedicated to the modeling of vertical mass transfers between the biofilm and the bulk flow, we have, in the first instance, presented the methodology used, followed by the presentation of various results obtained through analyses conducted on velocity fields, different fluxes, and overall transfer coefficients. Due to numerical constraints (resolution of relevant spatial scales), we have restricted the analysis to low Schmidt numbers (Sc=0.1, Sc=1, and Sc=10) and a single roughness Reynolds number (Re*=150). The analysis of instantaneous concentration fields from various simulations revealed logarithmic concentration profiles above the canopy. In this zone, the concentration is relatively homogeneous for longer times. The analysis of results also showed that the contribution of molecular diffusion to the total flux depends on the Schmidt number. This contribution is negligible for Schmidt numbers Sc≥0.1, but nearly balances the turbulent flux for Sc=0.1. In the canopy, the local Sherwood number, given by the ratio of the total flux (within or above the canopy) to the molecular diffusion flux at the wall, also depends on the Schmidt number and varies significantly between the canopy and the region above. The exchange velocity, a purely hydrodynamic parameter, is independent of the Schmidt number and is on the order of 10% of in the present case. This study also reveals that nutrient absorption by organisms near the wall depends on the Schmidt number. Such absorption is facilitated by lower Schmidt numbers.

关键词： Epilithic Biofilm Passive Scalar Transport Direct Numerical Simulation Navier-Stokes

Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cama Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200˙Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate

Recent research in mechanical properties of geopolymer-based ultrahigh-performance concrete:A review

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Defence Technology（防务技术） 2024年第2期32卷 67-88页

作者： g.Murali Division of Research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called geopolymer based ultra-highperformance concrete(gUHPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fighters in border *** this context,this article reviews the fresh state and mechanical properties of ***,the ingredients of gUHPC and fresh properties such as setting time and flowability are briefly ***,the review of compressive strength,flexure strength,tensile strength and modulus of elasticity of fibrous ***,the blast and projectile impact resistance performance was ***,the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder *** review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a higher dose of steel fibre to improve the microstructure of *** is hypothesized that the brittleness of gUHPC was mitigated by adding 1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering and *** the need for cement in gUHPC was a key factor in the review,indicating a promising potential for lowering carbon ***,gUHPC research is still in its early stages,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre geopolymer Silica fume Alkaline activators

Effects of frothers on bubbles size and flotation performance of hydrophobic minerals

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Journal of Central South University 2024年第7期31卷 2280-2299页

作者： gülşah gÜVEN Berivan TUNÇ ŞBeste AYDIN gülay BULUT Mineral Processing Engineering Department Faculty of MinesIstanbul Technical UniversityMaslak 34469IstanbulTurkey Research Center Metso OutotecKuparitie 1028101 PoriFinland

Frothers facilitate the reduction of bubbles size by preventing bubbles coalescence and produce more stable *** collision probability of the bubbles and particles substantially increases by decreasing bubble *** the same volume system,fewer bubbles result from a distribution of large-sized bubbles,and more bubbles result from a distribution of small-sized *** this research,fundamental two-phase frother characterization parameters were aimed to link with three-phase coal and talc flotation *** this purpose,the effect of single and dual frother systems on inhibiting bubble coalescence was investigated with methyl isobutyl carbinol(MIBC),isooctanol(2 ethyl hexanol),pine oil,and Dowfroth *** on the results of single frothers,isooctanol at the lowest critical coalescence concentration(CCC)value of 6×10^(−6) achieved the smallest bubbles with Sauter mean diameter of 0.80 *** blending Dowfroth 250 and pine oil,the bubbles size decreased significantly,reaching 0.45 *** the highest recoveries in coal flotation were obtained in single and frother blends where the bubbles size was measured as the smallest in two-phase system,and such a relationship was not found for talc flotation.

关键词： flotation frother blends bubble size coal and talc flotation

Nitrogen mineralization in the oldest climax communities in the eastern Mediterranean region

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Journal of Forestry Research 2024年第1期35卷 213-228页

作者： Fatma Selcen Sakar gürcan güleryüz Department of Biology Section Ecology GörükleGraduate School of Natural and Applied ScienceUniversity of Bursa Uludağ16059 NilüferBursaTurkey Department of Biology Section Ecology GörükleFaculty of Science and ArtsUniversity of Bursa Uludağ16059 NilüferBursaTurkey

In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest *** the oldest pure communi-ties of Pinus nigra(PN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 *** locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest *** had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),*** the lowest(30.5±4.2 kg ha^(-1) a^(-1)).Our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N *** acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.

关键词： Oldest forest communities Nitrogen mineralization Nitrification Tannic acid Total phenolic Litter

反应停(Thalidomide)治疗Jessner及Kanof氏病

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昆明医科大学学报 1984年第S4期 58-60页

作者： g.moulin 孙穆雍

1953年Jessner及Kanof描述的皮肤淋巴细胞浸润现已确定为一种良性皮肤病,病程长、易复发,组织学特点为真皮血管及附件周围有淋巴细胞浸润,表皮无变化。皮损一般呈多形性,常位于颊部和背部,表现为红斑丘疹,粉红色斑块,形态为环形,表皮无... 详细信息

1953年Jessner及Kanof描述的皮肤淋巴细胞浸润现已确定为一种良性皮肤病,病程长、易复发,组织学特点为真皮血管及附件周围有淋巴细胞浸润,表皮无变化。皮损一般呈多形性,常位于颊部和背部,表现为红斑丘疹,粉红色斑块,形态为环形,表皮无改变,不痒。在皮肤淋巴细胞浸润这一类病变中,本病已被认为是一种独立的疾病,它与结节病、梅毒、毒性皮炎(toxidermie)及酒渣鼻较易区别。虽然某些学者也曾将之归于红斑狼疮范围内,但

关键词：反应停酞胺哌啶酮 Thalidomide Jessner Kanof

“实证法学”的概念术语回顾与回归--基于文献的实证法学研究整合路径

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湖湘法学评论 2024年第1期4卷 21-49页

作者：熊谋林西南财经大学法学院四川成都611130

伴随着实证研究概念和范畴的思想大讨论,法学界在过去几十年涌现出大量相关的方法或学科术语。虽然各种术语本来根植于实证研究,但由于每种术语未对既有术语作细致的文献回顾和概念分析,而呈现出术语间前后矛盾、自我否定、相互攻击、... 详细信息

伴随着实证研究概念和范畴的思想大讨论,法学界在过去几十年涌现出大量相关的方法或学科术语。虽然各种术语本来根植于实证研究,但由于每种术语未对既有术语作细致的文献回顾和概念分析,而呈现出术语间前后矛盾、自我否定、相互攻击、相互整合的泛化和分化现象。从方法和学科层面来看,要实现实证研究的发展和繁盛,就必然需要在开放和团结的学术平台下统一学术理念,“实证法学”应该是整合研究队伍的最妥当路径。将当代实证法学研究的源头定位在二十世纪八十年代,了解钱学森和吴世宦所引领的法学研究方法大讨论对实证法学的影响,可以澄清有关起源问题的误解。实证法学的传统术语在早期都包含定量和定性,近十年才因个人理解或方法偏爱引发术语之争。新兴术语虽然在定量或定性、样本大小、理念内涵、技术方法上有所差异,但都是基于实证研究发展起来的,其术语之争也源于割裂文献所致的自创概念。回归实证研究的本质,停止术语和概念之争,只要正确和恰当地定义实证法学,便可以实现整合实证法学研究的目标。

关键词：法律实证实证主义法学社科法学计量法学计算法学数量法学数据法学数字法学

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Shell-model representations of the microscopic version of the Bohr–Mottelson collective model

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Communications in Theoretical Physics 2024年第8期76卷 81-92页

作者： H g ganev Joint Institute for Nuclear Research Dubna Russia Institute of Mechanics Bulgarian Academy of Sciences

The structure of the irreducible collective spaces of the group Sp（12, R）, which many-particle nuclear states are classified according to the chain Sp（12, R） ? U（6） ? SO（6） ? SUpn（3） ■SO（2） ? SO（3） of the proton–neutron symplectic model（PNSM）, is considered in detail. This chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr–Mottelson collective model. The construction of the relevant shell-model representations of the Sp（12, R） group along this chain is considered for three nuclei with varying collective properties and from different mass regions. It is shown that the SUpn（3） basis states of the Sp（12, R） representations belonging to the SO（6） irreps with seniority υ ≥ υ0, with υ0denoting the maximal seniority SO（6） irrep contained in the Sp（12, R） bandhead, are always Pauli allowed, but organized in a different way into different SO（6） shells. This is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm operation. Although the SUpn（3） multiplets within υ < υ0are not all Pauli forbidden, it is safe to discard them. The results obtained in the present work are important for the practical application of the microscopic version of the Bohr–Mottelson collective model.

关键词： microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model shell-model representations Sp(12, R) dynamical algebra

Harmonics in the Squirrel Cage Induction Motor Analytic Calculation Part III: Influence on the Torque-speed Characteristic

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 86-102页

作者： g.Kovács the ganz Electric Works BudapestHungary

The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the ***, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end.

关键词： Asynchronous parasitic torques Induction motor Squirrel cage rotor Space harmonics Synchronous parasitic torques