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On the microstructure and texture evolution in 17-4 PH stainless steel during laser powder bed fusion: Towards textural design

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Journal of Materials science & Technology 2022年第22期117卷 183-195页

作者： M.s.Moyle N.Haghdadi X.Z.Liao s.P.Ringer s.Primig school of Materials science&Engineering UNSW SydneyNSW 2052Australia Australian Centre for Microscopy&Microanalysis The University of SydneyNSW 2006Australia school of Aerospace Mechanical and Mechatronic EngineeringThe University of SydneyNSW 2006Australia

Additive Manufacturing (AM) of metals allows the production of parts with complex designs, offeringadvanced properties if the evolution of the texture can be controlled. 17-4 precipitation hardening (PH)stainless steel is a high strength, high corrosion resistance alloy used in a range of industries suitable forAM, such as aerospace and marine. Despite 17-4 PH being one of the most common steels for AM, thereare still gaps in the understanding of its AM processing–structure relationships. These include the natureof the matrix phase, as well as the development of texture through AM builds under different processingconditions. We have investigated how changing the laser power and scanning strategy affects the microstructure of 17-4 PH during laser powder bed fusion. It is revealed that the matrix phase is δ-ferritewith a limited austenite presence, mainly in regions of the microstructure immediately below melt *** fraction is independent of the printing pattern and laser power. However, reducing the timebetween adjacent laser passes during printing results in an increase in the austenite volume *** effect of the higher laser power, as well as additional remelting within the printing strategy, isan increase in the average grain size by epitaxial ferrite grain growth across multiple build layers andthe development of a mosaic type microstructure. Changes to the scanning strategy have significant impacts on the textures observed along the build direction, while (100) texture along the scanning directionis observed consistently. Mechanisms for texture formation and the mosaic structure are proposed thatpresents a pathway to the design of texture via AM process control.

关键词： Additive manufacturing 17-4 PH stainless steel Microstructure Texture

Gut microbiota in preterm infants receiving breast milk or mixed feeding

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World Journal of Clinical Pediatrics 2024年第2期13卷 135-145页

作者： sandra Gabriela sánchez-González Bárbara Gabriela Cárdenas-del-Castillo Elvira Garza-González Gerardo R Padilla-Rivas Isaías Rodríguez-Balderrama Consuelo Treviño-Garza Fernando Félix Montes-Tapia Gerardo C Palacios-saucedo Anthony Gutiérrez-Rodríguez Manuel Enrique de-la-O-Cavazos Department of Pediatrics Hospital Universitario“Dr.JoséEleuterio González”Universidad Autónoma de Nuevo LeónMonterrey 64460Nuevo LeónMéxico Departamento de Bioquímica y Medicina Molecular Universidad Autónoma de Nuevo LeónMonterrey 64460Nuevo LeónMéxico Department of Biochemistry and Molecular Medicine Universidad Autónoma de Nuevo LeónMonterrey 64460Nuevo LeónMéxico Department of Pediatric surgery Hospital Universitario"Dr.JoséEleuterio González"Monterrey 64460Nuevo LeónMéxico

BACKGROUND Preterm birth is the leading cause of mortality in newborns,with very-low-birthweight infants usually experiencing several *** milk is considered the gold standard of nutrition,especially for preterm infants with delayed gut colonization,because it contains beneficial microorganisms,such as Lactobacilli and *** To analyze the gut microbiota of breastfed preterm infants with a birth weight of 1500 g or *** An observational study was performed on preterm infants with up to 36.6 wk of gestation and a birth weight of 1500 g or less,born at the University Hospital ***éEleuterio González at Monterrey,Mexico.A total of 40 preterm neonates were classified into breast milk feeding(BM)and mixed feeding(MF)groups(21 in the BM group and 19 in the MF group),from October 2017 to June *** samples were collected before they were introduced to any feeding *** full enteral feeding was achieved,the composition of the gut microbiota was analyzed using 16s rRNA gene *** variables were compared using student’s t-test or using the Mann–Whitney U test for nonparametric ***,evenness,equitability,Margalef’s index,Fisher’s alpha,Chao-1 index,and shannon’s diversity index were also *** No significant differences were observed at the genus level between the *** comparison indicated higher counts of Alphaproteobacteria and Betaproteobacteria in the initial compared to the final sample of the BM group(Ps of Gammaproteobacteria were detected in the final than in the initial sample(P=0.040).According to the Margalef index,Fisher’s alpha,and Chao-1 index,a decrease in species richness from the initial to the final sample,regardless of the feeding type,was observed(Pyla were Bacteroidetes,Actinobacteria,Firmicutes,and Proteobacteria,with Proteobacteria being the most ***,no significant differences were

关键词： Gut microbiota Human milk Preterm infant Proteobacteria Very low birth weight 16s rRNA

Effects of Poisson's Ratio on Band Gaps of Two-Dimensional solid/solid Phononic Crystals

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Effects of Poisson's Ratio on Band Gaps of Two-Dimensional S...

“心存即为乡”：清代朝鲜使者对“高丽铺”历史的构建

The 16th Annual Conference of Hong Kong society of Theoretical and Applied Mechanics 2012、The 1st Mainland-Hong Kong youth Forum on Mechanics 2012、The 8th shanghai-Hong Kong Forum on Mechanics and Its Application 2012

作者： T.X.Ma X.X.su y.F.Wang y.s.Wang Institute of Engineering Mechanics Beijing Jiaotong University school of Electronic and Information Engineering Beijing Jiaotong University

since the 1990s,there has been a great deal of work devoted to the study of phononic crystals(PCs).The existence of a phononic band gap(PBG) where the propagation of the acoustic or elastic waves is forbidden leads to many engineering *** the PBG tuning mechanism is always an important aspect of the theoretical studies of PCs. In this paper,we study the effects of the Poisson's ratios on the PBGs in two-dimensional(2D) solid-solid square-latticed *** to the theoretical importance and practical application of the auxetic material,the effect of negative Poisson's ratio is also considered in the present work. For the in-plane wave mode,the material parameters determining PBGs include the velocity ratio,the acoustic impedance ratio and the Poisson's ratios of the two component materials[1].We investigate the influences of the Poisson's ratio on 2D square-latticed PCs with given values of the velocity ratio and acoustic impedance *** different combinations of the velocity ratio and acoustic impedance ratio correspond to the large impedance ratio with small mismatch in the transverse wave velocities,small velocity ratio with small mismatch in the acoustic impedances and small impedance ratio with small mismatch in the wave *** PBGs between the 2nd and 3rd,3rd and 4th bands are *** are usually the first or second PBGs. For the PCs with large impedance ratio and small mismatch in the wave velocities,the PBG is influenced slightly by the Poisson's ratio of the host,but significantly by that of the inclusion when its value is *** the PCs with small velocity ratio and small mismatch in the acoustic impedances,the PBGs between the 3rd and 4th bands are sensitive to the Poisson's ratios of both the host and inclusion;those between the 2nd and 3rd bands are influenced significantly by the Poisson's ratio of the inclusion and become wider as the Poisson's ratio of the inclusion *** the PCs with small impedance rati

关键词： Poisson Effects of Poisson's Ratio on Band Gaps of Two-Dimensional solid/solid Phononic Crystals

来源： cnki会议评论

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社会科学 2013年第2期 155-163页

作者：黄普基[韩] 南京大学历史系江苏南京210093

"高丽铺"是明清时期朝鲜朝贡路上的一个村落。朝鲜使者只要路经此地,便会留下记录。最初,高丽铺在朝鲜人的笔下,只是他们用以寄托怀乡之情的对象;之后,其与朝鲜的关系却一步步地被确认和强化,以致最终成为了朝鲜使者心目中"中原中的朝鲜... 详细信息

"高丽铺"是明清时期朝鲜朝贡路上的一个村落。朝鲜使者只要路经此地,便会留下记录。最初,高丽铺在朝鲜人的笔下,只是他们用以寄托怀乡之情的对象;之后,其与朝鲜的关系却一步步地被确认和强化,以致最终成为了朝鲜使者心目中"中原中的朝鲜"、"异域中的故乡"。然而,这不过是几代朝鲜人集体虚构出来的"历史记忆"而已,并非历史事实。透过此一虚构过程,我们可以把握朝鲜人在明清易代这一特殊的历史背景下的愿望、想象等思想世界。

关键词：朝鲜使者《燕行录》高丽铺还乡河

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Gomila Mallorca

世界建筑导报 2024年第3期39卷 50-50页

作者： MVRDV GRAs Reynés Arquitectos MVRDV+GRAs Reynés Arquitectos

构成马略卡岛帕尔马Gomila项目七座建筑中的前五座已于日前完工。Gomila项目由MVRDV和GRAs Reynés Arquitectos联合设计,为一系列建筑的集合,每栋建筑都因其颜色、材料和屋顶线而具有自己的个性。本项目正在逐步改变El Terreno附近的Go... 详细信息

构成马略卡岛帕尔马Gomila项目七座建筑中的前五座已于日前完工。Gomila项目由MVRDV和GRAs Reynés Arquitectos联合设计,为一系列建筑的集合,每栋建筑都因其颜色、材料和屋顶线而具有自己的个性。本项目正在逐步改变El Terreno附近的Gomila广场周边区域。Gomila项目一期工程完成后,总共增加了60套不同规模和类型的新住宅,以及新的商业空间,该项目已经逐步将El Terreno复兴为一个充满活力、绿色、可持续的住宅区。

关键词：商业空间住宅区一期工程 Mall MVRDV 绿色周边区域可持续的

Design and analysis of intrusion detection systems for wireless mesh networks

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Digital Communications and Networks 2022年第6期8卷 1068-1076页

作者： Fawaz s.Al-Anzi P.O.Ox 5969 safat 13060 Computer Engineering DepartmentKuwait UniversityKuwait

Intrusion is any unwanted activity that can disrupt the normal functions of wired or wireless networks. Wireless mesh networking technology has been pivotal in providing an affordable means to deploy a network and allow omnipresent access to users on the Internet. A multitude of emerging public services rely on the widespread, high-speed, and inexpensive connectivity provided by such networks. The absence of a centralized network infrastructure and open shared medium makes WMNs particularly susceptible to malevolent attacks, especially in multihop networks. Hence, it is becoming increasingly important to ensure privacy, security, and resilience when designing such networks. An effective method to detect possible internal and external attack vectors is to use an intrusion detection system. Although many Intrusion Detection systems (IDss) were proposed for Wireless Mesh Networks (WMNs), they can only detect intrusions in a particular layer. Because WMNs are vulnerable to multilayer security attacks, a cross-layer IDs are required to detect and respond to such attacks. In this study, we analyzed cross-layer IDs options in WMN environments. The main objective was to understand how such schemes detect security attacks at several OsI layers. The suggested IDs is verified in many scenarios, and the experimental results show its efficiency.

关键词： Wireless Mesh network Intrusi on detection Cross-layer security

Electrical and dielectric characterization of Au/ZnO/n-si device depending frequency and voltage

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Chinese Physics B 2017年第2期26卷 477-483页

作者： I Orak A Kocyigit s Ahndal Bingol University Vocational School of Health Services 12000 Bingol Turkey Bingol University Faculty of Sciences and Arts Department of Physics 12000 Bingol Turkey Igdir University Engineering Faculty Department of Electrical Electronic Engineering 76000 Igdir Turkey Gazi Universty Faculty of Sciences Department of Physics 06500 Ankara Turkey

Au/Zn O/n-type si device is obtained using atomic layer deposition（ALD） for Zn O layer, and some main electrical parameters are investigated, such as surface/interface state（Nss）, barrier height（Φb）, series resistance（Rs）, donor concentration（Nd）, and dielectric characterization depending on frequency or voltage. These parameters are acquired by use of impedance spectroscopy measurements at frequencies ranging from 10 k Hz to 1 MHz and the direct current（DC） bias voltages in a range from-2 V to ＋2 V at room temperature are used. The main electrical parameters and dielectric parameters,such as dielectric constant（ε＂）, dielectric loss（ε＂）, loss tangent（tan δ）, the real and imaginary parts of electric modulus（M and M）, and alternating current（AC） electrical conductivity（σ） are affected by changing voltage and frequency. The characterizations show that some main electrical parameters usually decrease with increasing frequency because charge carriers at surface states have not enough time to fallow an external AC signal at high frequencies, and all dielectric parameters strongly depend on the voltage and frequency especially in the depletion and accumulation regions. Consequently, it can be concluded that interfacial polarization and interface charges can easily follow AC signal at low frequencies.

关键词： Au/ZnO/n–si device dielectric properties polarization process frequency and voltage dependence

septic arthritis of the hand: From etiopathogenesis to surgical treatment

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World Journal of Orthopedics 2022年第11期13卷 993-1005页

作者： Konstantin V Lipatov Arthur Asatryan George Melkonyan Aleksandr D Kazantcev Ekaterina I solov’eva Irina V Gorbacheva Alexander s Vorotyntsev Andrey y Emelyanov General surgery Department Institute of Clinical Medicine named after N.V.SklifosovskySechenov First Moscow State Medical University(Sechenov University)Moscow 119021Russia General surgery Department State Budgetary Institution“City Clinical Hospital named after S.S.Yudin of Moscow Healthcare Department”Moscow 115142Russia General surgery Department The Hospital for War Veterans N3Moscow 129336Russia General surgery Department I.M.Sechenov First Moscow State Medical UniversityMoscow 119991Russia

BACKGROUND septic arthritis of the hand,which is the second most common after damage of the knee joint,remains one of the leading causes of temporary *** inflammation can cause dysfunction of the joint,and in the most severe cases,the need for amputation of the finger may *** results of their treatment today,especially from a functional point of view,cannot be considered *** surgical treatment is extremely important in septic arthritis of the hand,as it helps to prevent cartilage destruction and the development of *** To explore the features of the course of septic arthritis of the hand as well as approaches to surgical treatment and its results,depending on the nature of the damage to the articular *** The results of the treatment of 170 patients with septic arthritis of the hand,which were treated in the period of 2020-2021,were *** of the interphalangeal and metacarpophalangeal joints(MCP)of fingers 1,2,and 3 was more often noted in 147(81.6%)*** most common cause of arthritis was a penetrating injury as a result of household trauma(101,59.4%),animal bite(30,17.6%),and clenched fist injury(15,8.8%).septic arthritis with contiguous osteomyelitis was observed in 98(54.4%)*** treatment was completed with drainage and irrigation of the *** mobilization was used to restore *** patients with osteomyelitis,it was aimed at the formation of *** was not ***-term results of treatment were assessed in 142(83.5%)patients within 1 mo to 12 mo after discharge from the hospital[the median was 7 mo(IQR:4-9)].REsULTs The most commonly isolated organism was staphylococcus aureus(35.3%).The median treatment delay in patients without osteomyelitis was 5 d(IQR:4-7);for septic arthritis with contiguous osteomyelitis,it was 14 d(IQR:5-21).Radiography for osteomyelitis within 2 wk was uninformative:41.2%of diagnoses.A single surgical treatment was

关键词： septic arthritis Osteomyelitis Hand surgical treatment Neoarthrosis

Properties of the πh9/2 × vi13/2 Oblate Band in ^188Tl

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Chinese Physics Letters 2006年第7期23卷 1727-1730页

作者：马龙周小红邢烨炳张玉虎郭应祥雷相国谢成营 Oshima M. Toh y. Koizumi M. Osa A. Hatsukawa y. sugawara M. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 japan Atomic Energy Research Institute Tokai Ibaraki 319-1195 Japan Chiba Institute of Technology Narashino Chiba 275-0023 Japan

High spin states in ^188Tl have been investigated via the 157Gd（^35Cl,4n） reaction at beam energy of 170 MeV. A rotational band built on the πh9/2 × vi13/2 configuration with oblate deformation has been established. Considering the similarity between the band structure observed in odd-odd Tl nuclei, spin values have been tentatively proposed for the new band in ^188Tl. The πh9/2 × vi13/2 oblate band in ^188Tl shows low-spin signature inversion, and it can be interpreted qualitatively by the two quasiparticle plus rotor model including a J-dependent p-n residual interaction.

关键词： πh9/2νi13/2 Oblate 188Tl interpreted qualitatively