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Seismic response of concrete gravity dam reinforced with FRP sheets on dam surface

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Water Science and Engineering 2013年第4期6卷 409-422页

作者： Hong ZHONG Na-li WANG Gao LIN Faculty of Infrastructure Engineering Dalian University of Technology ACRE Coking and Refractory Engineering consulting Corporation MCC

This paper aims at exploring the effects of anti-seismic reinforcement with the fiber-reinforced polymer （FRP） material bonded to the dam surface in dam engineering. Time-history analysis was performed to simulate the seismic failure process of a gravity dam that was assumed to be reinforced at the locations of slope discontinuity at the downstream surface, part of the upstream face, and the dam heel. A damage model considering the influence of concrete heterogeneity was used to model the nonlinearity of concrete. A bond-slip model was applied to the interface between FRP and concrete, and the reinforcement mechanism was analyzed through the bond stress and the stress in FRP. The results of the crack pattern, displacement, and acceleration of the reinforced dam were compared with those of the original one. It is shown that FRP, as a reinforcement material, postpones the occurrence of cracks and slows the crack propagation, and that cracks emanating from the upstream surface and downstream surface are not connected, meaning that the reinforced dam can retain water-impounding function when subjected to the earthquake. Anti-seismic reinforcement with FRP is therefore beneficial to improving the seismic resistant capability of concrete dams.

关键词： Key words: FRP sheet reinforcement of concrete gravity dam bond behavior seismic damagesimulation time history analysis

Multi-process and multi-pollutant control technology for ultra-low emissions in the iron and steel industry

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Journal of Environmental Sciences 2023年第1期123卷 83-95页

作者： Tingyu Zhu Xindong Wang Yong Yu Chao Li Qun Yao Yuran Li Institute of Process Engineering Chinese Academy of SciencesBeijing 100190China HBIS Group Co. Ltd.Shijiazhuang 050023China ACRE Coking&Refractory Engineering consulting Corporation MCCDalian 116085China Sinosteel Tiancheng Environmental Protection Science&Technology Co.Ltd. Wuhan 430205China

The iron and steel industry is not only an important foundation of the national economy,but also the largest source of industrial air *** to the current status of emissions in the iron and steel industry,ultra-low pollutant emission control technology has been researched and ***-phase proportion control technology has been developed for magnesian fluxed pellets,and a blast furnace smelting demonstration project has been established to use a high proportion of fluxed pellets(80%)for the first time in China to realize source emission reduction of SO_(2)and NO_(x).Based on the characteristics of high NO_(x)concentrations and the coexistence of multiple pollutants in coke oven flue gas,low-NO_(x)combustion coupled with multi-pollutant cooperative control technology with activated carbon was developed to achieve efficient removal of multiple pollutants and resource utilization of *** on the characteristics of co-existing multiple pollutants in pellet flue gas,selective non-catalytic reduction(SNCR)coupled with ozone oxidation and spray drying adsorption(SDA)was developed,which significantly reduces the operating cost of the *** the light of the high humidity and high alkalinity in flue gas,filter materials with high humidity resistance and corrosion resistance were manufactured,and an integrated pre-charged bag dust collector device was developed,which realized ultralow emission of fine particles and reduced filtration resistance and energy consumption in the *** source emission reduction,process control and end-treatment technologies,five demonstration projects were built,providing a full set of technical solutions for ultra-low emissions of dust,SO_(2),NO_(x),SO_(3),mercury and other pollutants,and offering technical support for the green development of the iron and steel industry.

关键词： Iron and steel industry air pollution whole-process control ultra-low emission

Effect of Copper on Growth Characteristics and Disease Control of the Recently Introduced <i>Guignardia citricarpa</i>on Citrus in Florida

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American Journal of Plant Sciences 2013年第2期4卷 282-290页

作者： Katherine E. M. Hendricks Ryan S. Donahoo Pamela D. Roberts Mary C. Christman mcc statistical consulting llc Gainesville USA Southwest Florida Research and Education Center University of Florida-IFAS Immokalee USA

Guignardia citricarpa, the plant pathogenic fungus that causes citrus black spot, was recently introduced into the United States. The development of this disease in the presence of multiple applications of copper per year to manage citrus canker warrants an investigation into the effects of copper on growth of isolates of G. citricarpa from citrus in Florida. Guignardia citricarpa and G. mangiferae isolates, confirmed by internal transcribed spacer (ITS) sequencing of ribosomal DNA and DNA homology, were inoculated on non-amended media and media amended with 50 and 500 μg·ml-1 copper sulfate. Radial colony growth was assessed over a 26 to 59 day period. Copper reduced the growth of G. citricarpa isolates in media amended with 500 μg·ml-1 copper but had variable effects on radial growth in media amended with 50 μg·ml-1 copper. There was little effect of copper on the in vitro growth of G. mangiferae isolates. Field application of copper with and without an adjuvant for the control of citrus black spot was undertaken in a commercial grove in Florida in 2011. Spray applications were made on a 23.3 ± 4.7 day interval and fruit accessed between December 2011 and March 2012 for black spot symptoms. Copper failed to reduce the proportion of fruit exhibiting symptoms compared to that of the controls.

关键词： Copper Tolerance Citrus Black Spot Guignardia mangiferae Saprophyte Citrus x sinensis

Relationship between crystallographic structure of complex inclusions MgAl_(2)O_(4)/Ti2O_(3)/MnS and improved toughness of heat-affected zone in shipbuilding steel

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Journal of Iron and Steel Research(International) 2022年第8期29卷 1277-1290页

作者： Yan Wang Li-guang Zhu Jin-xia Huo Qing-jun Zhang Yao-guang Wu Wei Chen Shuo-ming Wang College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina College of Materials Science and Engineering Hebei University of Science and TechnologyShijiazhuang 050018HebeiChina China Analysis and Testing Center North China University of Science and TechnologyTangshan 063210HebeiChina mcc Capital Engineering&Research Incorporation Limited Metallurgical Engineering Consulting and Design DivisionBeijing 100176China

In accordance with the minimum degree of disregistry mechanism in oxide metallurgy, the intragranular acicular ferrite (IAF) generated by microalloying elements in austenite was studied. Herein, the effect of Mg treatment on the microstructure and toughness of the heat-affected zone (HAZ) in shipbuilding steel was investigated. Mg treatment produced inclusions that influenced the formation of acicular ferrite in the microstructure. This refined the HAZ microstructure and improved its toughness. Electron backscatter diffraction was used to determine the oxides of titanium and the MgO Al_(2)O_(3) or MgAl_(2)O_(4) complex inclusions that induced the formation of IAF. MnS precipitated on MgAl_(2)O_(4) on a specific habit plane and in a specific direction. MnS had a specific orientation relationship with MgAl_(2)O_(4), i.e., f100gMgAl_(2)O_(4) //{100}MnS. The 35-mm-thick plate obtained in the industrial test after welding at a welding heat input of 120 kJ/cm had an average impact absorbed energy of 282.7 J at - 40 ℃ and 2 mm from the weld joint in the HAZ. The twodimensional disregistry index between inclusions can be used as the basis for controlling their distribution and adsorption force. Microalloy addition in the order of Al-Mg-Ti is key to obtaining abundant dispersion and fine nucleation in austenite.

关键词： High heat input welding Mg treatment Disregistry mechanism Heat-affected zone

Forage breeding and cultivar development:A 50-year perspective

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Grassland Research 2023年第2期2卷 97-105页

作者： Joseph Henry Bouton Institute of Plant Breeding Geneticsand GenomicsUniversity of GeorgiaAthensGeorgiaUSA Bouton consulting Group LLCAthensGeorgiaUSA

This article represents the perspective of one retired,academic forage breeder and cultivar developer after 50 years of working *** cultivars that help farmers within pastoral agriculture is the main goal,a system where livestock is the *** Grassland Congress proceedings,as well as the general literature,are historical guides for the state of forage *** was achieved through technologies;better equipment for planting and harvesting;and advances in computer computation and *** achievements were fitful and continue to *** performance mean-reversion,cost to the program,and what the farmer seed buyer was willing to pay are important considerations for applying any technology,especially *** promises were too *** was due,in part,to a lack of understanding that traditional phenotypic/genotypic field selection programs operate in a complex way with multiple species and several traits screened simultaneously at a modest *** majority of current forage cultivars are from field-based *** participation at scientific conferences declined over time,with less sharing of information the *** developers will continue using basic field selection methods but should explore applying any technology;just be clever on when,how,and with whom to use *** advice and experiences are also presented and discussed.

关键词： biotechnologies breeding cultivars farmers forages genetics livestock pastures

Three-dimensional simulation of liquid injection,film formation and transport,in fluidized beds

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Particuology 2009年第5期7卷 337-346页

作者： Paul Zhao Peter J. O'Rourke Dale Snider CPFD Software LLCAlbuquerqueNM 87111USA CFD d'OR Software and consulting LLCLos AlamosNM 87544USA

Liquid injection, and film formation and transport in dense-phase gas-solids fluidized beds are numerically simulated in three dimensions using a collisional exchange model that is based on the mechanism that collisions cause transfer of liquid mass, momentum, and energy between particles. In the model, each of the particles is represented by a solid core and a liquid film surrounding the core. The model is incorporated in the framework of the commercial code Barracuda developed by CPFD Software. The commercial software is an advanced CFD-based computational tool where the particles are treated as discrete entities, calculated by the MP-PIC method, and tracked using the Lagrangian method. Details of the collisional liquid transfer model have been previously presented in O＇Rourke, Zhao, and Snider （2009）; this paper presents new capabilities and proof-testing of the collision model and a new method to better quantify the penetration length. Example calculations of a fluidized bed without liquid injection show the expected effect of collisions on the reduction of granular temperature （fluctuational kinetic energy） of the bed. When applied to liquid injection into a dense-phase fluidized bed under different conditions, the model predicts liquid penetration lengths comparable to the experiments. In addition, the simulation reveals for the first time the dynamic mixing of the liquid droplets with the bed particles and the transient distribution of the droplets inside the bed.

关键词： MP-PIC Liquid injection Fluidized bed Particle collisions CPFD Jet penetration

Bioinformatic Analysis of SARS-CoV-2 Genomes to Develop a Universal Coronavirus Vaccine

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Journal of Biosciences and Medicines 2022年第10期10卷 84-97页

作者： Anya Vaish James McSwiggen Tesla STEM High School Redmond USA McSwiggen Biotech consulting llc Arvada USA

COVID-19 is caused by the SARS-CoV-2 virus. Current RNA vaccines Pfizer/BioNTech’s BNT162b2 and Moderna’s mRNA-1273 are more than 94% successful in preventing infection. The spike protein of the virus is essential for the interaction and internalization of the virus in the host cell and is considered a prime target for vaccine development against the SARS virus. This study aims to identify highly conserved sequences in spike protein or other sections of the viral genome that can potentially be used to develop a universal coronavirus vaccine. Bioinformatic analysis of 258,269 full-length SARS-CoV-2 genomic sequences in the NCBI database was carried out using a custom Perl Script. All sequences were compared to the spike protein and full-length viral genome reference to find 100 nucleotide-long segments that were at least 99% conserved across SARS-CoV-2 sequences. The analysis resulted in a >99.5% conserved 114-nucleotide segment on the spike protein and a 99.49% conserved 104-nucleotide segment on the non-spike protein section of the viral genome. The conserved sequences from this study may be useful in developing an RNA or protein vaccine that may be effective against future SARS-CoV-2 strains or could act as a universal vaccine if these sequences are present in other coronavirus families.

关键词： Coronavirus S-Protein Spike Protein Conservation Universal Vaccine Bioinformatics

On the Effects of Driven Element L/D Ratio and Length in VHF-SHF Yagi-Uda Arrays

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Wireless Engineering and Technology 2023年第1期14卷 1-25页

作者： Richard A. Formato consulting Engineer & Registered Patent Attorney of Counsel Emeritus Cataldo & Fisher LLC Harwich MA USA

While the Yagi-Uda array has been studied for decades, one issue appears to have received less attention than perhaps it should, namely, the effects on performance of the array’s driven element length and its length-to-diameter ratio. This paper looks at that question. It shows that decreasing the L/D ratio increases impedance bandwidth, but it may shift the IBW band sufficiently far from the design frequency that other parameters such as gain and front-to-back ratio probably are adversely affected. It also shows that array performance is not relatively independent of element diameters. This paper also investigates the effect of lengthening the driven element, which can substantially improve IBW. Several iterations of a 3-element prototype and improved arrays are modeled with the Method of Moments and discussed in detail. A five step design procedure is recommended and applied to a Genetic Algorithm-optimized 3-element Yagi at 146 MHz. This array exhibits excellent performance in terms of gain, front-to-back ratio, and especially impedance bandwidth (nearly 14% for voltage standing wave ratio ≤ 2:1 with two frequencies at which 50 ? is almost perfectly matched). While the analysis and recommended design steps are applied to cylindrical array elements, which commonly are aluminum tubing for stand-alone VHF-SHF Yagis, they can be applied to other element geometries as well using equivalent cylindrical radii, for example, Printed Circuit Board traces for planar arrays. One consequence of lengthening the driven element while reducing its L/D ratio is that some reactance is introduced at the array feedpoint which must be tuned out, and two approaches for doing so are suggested.

关键词： Yagi Array Driven Element Impedance Bandwidth

Features Desired in Public Transport in a Developing City: Users’ Perspective

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Journal of Transportation Technologies 2023年第4期13卷 632-643页

作者： Md. Nafis Imtiyaz Md. Golam Sobhani Mostafiz Emtiaz Arcadis US Inc. Houston USA Ardaman and Associates Inc. St. Rose USA RRP consulting Engineers LLC Houston USA

Excessive growth of population and urbanization in the developing countries set an increasing demand of mobility services. To meet this demand, public transport plays a significant role by providing an easy and affordable mobility service. Public transport service is a process evolving over time nevertheless is not always directly responsive to the changing demand of the passengers. Recently in developing countries, the unpleasant experience in public transport services is seen as one of the main reasons behind increased passenger car share, which eventually lead to traffic congestion. However, the situation can be ameliorated if the features of the public transport are improved by addressing the users’ demand. In this study, the primary features desired and demanded by the passengers of a developing country are identified by three phase survey. These identified features are also categorized based on public responses. And finally, the required features in an appropriate public transport mode are prioritized by using a common Multi Criteria Decision Making approach (AHP—Analytic Hierarchy Process). The study suggests that residents of the developing city are not that much concern on the outlook and ambience of the service rather they are concerned about finishing their trips safely in time at an affordable rate. The findings of this research will help planners and decision makers to make the best use of the investment in public transport services and infrastructure to promote these modes over privately owned vehicle.

关键词： Public Transport Feature Analytical Hierarchy Process (AHP) Questionnaire Respondents Weightage