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In order to realize the smelting effect of high oxygen supply intensity in large and medium-sized converters, a new six hole oxygen lance nozzle with double angle, double flow and staggered double structure is designed in this paper, and the jet characteristics are compared with those of the traditional structure oxygen lance. According to the theory of fluid dynamics and the principle of similarity, the velocity attenuation of the centerline of the jet and the longitudinal section of the oxygen jet are tested by using the oxygen gun jet detection experimental system. The results show that the jet performance of the staggered double structure six hole oxygen lance nozzle is better than that of the traditional structure oxygen lance nozzle. When the ratio of large hole flow is 55%-65%, the angle of large hole is 12°-14°and the angle of small hole is 16°-18°, the ratio of hole flow plays a leading role in the size of jet velocity. The greater the flow distribution, the greater the jet velocity. Using staggered double structure six hole oxygen lance can improve the stirring force of the jet to the molten pool.

To achieve the smelting effect of low splash in large and medium-sized converters, the jet flow field simulated by compressed air at room temperature is studied by the oxygen lance (OL) jet detection experimental system in this paper. This paper mainly analyzes the variation law of jet velocity at the geometric axis of the OL nozzle and scalar distribution and attenuation of jet isovelocity line at different cross sections. The results show that the oxygen jet cross-section of all OL nozzles gradually expands with the rise of OL position. When the large hole flow ratio is between 55% and 65%, the large hole angle is between 12° and 14° and the small hole angle is between 16° and 18°, therefore the angle of hole plays a significant role in the impact radius. The larger the angle is, the larger the impact radius is. The area of action between jet and molten pool could be enlarged by staggered double-structure six-hole OL.

Large-scale copper smelting bottom-blown furnace (BBF) plays an important role in the modern copper smelting industry. Compared with small and medium-sized BBFs, the characteristics of oxygen lances have changed greatly. Pneumatic mixing with the oxygen lance seat as a blowing unit has become a disturbance source in the furnace. The arrangement of the oxygen lance seat directly affects the smelting effect of large-scale BBF. This paper takes a large BBF in a smelter as the research object, establishes a local model based on the lance seat, and analyzes the influence of two oxygen lance seat parameters on the flow characteristics of the molten pool through computational fluid dynamics (CFD) numerical simulation. The results show that the lance seat angle and the distance between two oxygen lances have significant effects on the bubble floating path and the effective mixing zone range, respectively. Reducing the lance seat angle appropriately will extend the bubble floating movement space, and increasing the distance between two lances appropriately will weaken the overlap of the effective mixing zone. Rotating the furnace body or resetting oxygen lances is recommended, which is conducive to strengthening the smelting process of large BBF.

The basic oxygen furnace (BOF) is the dominating primary steelmaking process. It is an autothermal process where hot metal and scrap are used as charging materials. The decarbonization and transformation of integrated BOF steelmaking will be the most important challenge in the coming years. Steel scrap is a charge material without new CO2 emissions, whose availability is expected to grow significantly and will play a key role in this decarbonization process. Several solutions have been developed by Primetals Technologies to provide additional energy for processing higher scrap rates in integrated BOF steelmaking. Such solutions include simple upgrade packages installed on existing converters such as process models for heat optimization, post-combustion, and scrap preheating lances. For higher scrap rates from 30% to 50%, a combination blowing converter and JET converter is required to provide sufficient mixing during scrap melting and the highest heat transfer from the increased post-combustion. Hybrid EAF–BOF operation and limitations regarding scrap quality also need to be considered for the transformation of steelmaking. Scrap sorting and processing can be a solution to reduce residual levels in crude steel for high scrap rates. Based on reference plant data, the CO2 reduction potential of the presented solution versus the effort and complexity of implementation is compared.

Background Infants born very and extremely premature (V/EPT) are at a significantly elevated risk for neurodevelopmental disorders and delays even in the absence of structural brain injuries. These risks may be due to earlier-than-typical exposure to the extrauterine environment, and its bright lights, loud noises, and exposures to painful procedures. Given the relative underdeveloped pain modulatory responses in these infants, frequent pain exposures may confer risk for later deficits. Methods Resting-state fMRI scans were collected at term equivalent age from 148 (45% male) infants born V/EPT and 99 infants (56% male) born at term age. Functional connectivity analyses were performed between functional regions correlating connectivity to the number of painful skin break procedures in the NICU, including heel lances, venipunctures, and IV placements. Subsequently, preterm infants returned at 18 months, for neurodevelopmental follow-up and completed assessments for autism risk and general neurodevelopment. Results We observed that V/EPT infants exhibit pronounced hyperconnectivity within the cerebellum and between the cerebellum and both limbic and paralimbic regions correlating with the number of skin break procedures. Moreover, skin breaks were strongly associated with autism risk, motor, and language scores at 18 months. Subsample analyses revealed that the same cerebellar connections strongly correlating with breaks at term age were associated with language dysfunction at 18 months. Conclusions These results have significant implications for the clinical care of preterm infants undergoing painful exposures during routine NICU care, which typically occurs without anesthesia. Repeated pain exposures appear to have an increasingly detrimental effect on brain development during a critical period, and effects continue to be seen even 18 months later.

The World Health Organization developed theTricycle surveillance programme to obtain a global picture of antimicrobial resistance, especially in countries with limited surveillance capacity. The programme was developed within a One Health perspective. Tricycle provides a framework for applying a standardized technical protocol to determining the prevalence of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli in three sectors: the human, animal and environment sectors. Regular use of the protocol would enable information to be obtained on time trends and on inter- and intraregional variations, thereby generating dynamic data on antibacterial resistance for decision-makers.To date, 19 countries have begun implementing theTricycle protocol, while other countries will start implementation in the coming years. The Network for Enhancing Tricycle ESBL Surveillance Efficiency (NETESE) was established to support countries implementing theTricycle protocol. Currently, NETESE includes representatives from 15 institutions in eight low- or middle-income countries at different stages of Tricycle protocol implementation, and from four European countries involved in devising the protocol.This paper describes theTricycle protocol, reports the initial experiences of NETESE participants with its implementation and discusses future challenges and opportunities.

The Ward error sum of squares hierarchical clustering method has been very widely used since its first description by Ward in a 1963 publication. It has also been generalized in various ways. Two algorithms are found in the literature and software, both announcing that they implement the Ward clustering method. When applied to the same distance matrix, they produce different results. One algorithm preserves Ward’s criterion, the other does not. Our survey work and case studies will be useful for all those involved in developing software for data analysis using Ward’s hierarchical clustering method.

Gas-metal-slag interaction with traditional oxygen lance and single-flow postcombustion (PC) lance is compared by fluid volume method (VOF). Then, the industrial trials are carried out in a 120-ton top-blown converter to evaluate their metallurgical effects. Simulation results indicate that oxygen jet is injected to the liquid bath, generating a cavity. The liquid bath appears to have an unstable flow condition. Compared with the traditional lance, the PC lance is more helpful for stirring and mixing of liquid bath. The cavity diameter and depth with the PC lance are increased by 5.8% and 4.3%, respectively. Additionally, an improved model is proposed, which considers the momentum superposition of secondary flow and modifies the value of K characterizing the velocity attenuation. Industrial tests show that many metallurgical properties have been optimized by the PC lance, for example, the blowing time shortens by 93 s, the dephosphorization rate increases by 1.67%, and the scrap ratio increases by 1.3%.

Based on northern (NOL) and southern (SOL) mitochondrial lineages, recently, it proposed the new species Ammodytes heian and revived the species name Ammodytes japonicus to describe sand lances from the northwestern Pacific Ocean. This study used molecular methods to investigate genetic relationships between the two sand lance species in Korea and Japan. In total, 154 specimens were collected from four locations in Korea (Baengnyeongdo in the Yellow Sea, Tongyeong in the Korean Strait, and Jumunjin and Gijang in the East Sea), and 50 specimens were collected from a single location in Japan (Wakkanai in the Okhotsk Sea). Mitochondrial DNA analysis demonstrated that the individuals from Baengnyeongdo and Tongyeong all belonged to the SOL, whereas those from Gijang, Jumunjin, and Wakkanai included individuals from both the NOL and SOL (over 75% NOL). Population structure analyses were performed on the same individuals using seven microsatellite DNA markers. The population structure analysis based on 201 specimens identified two clusters (named as northern group and southern group), with the admixture proportion (q) of < 0.1 for the northern group in the Backyeongdo and Tongyeong sand lances and < 0.1 for the southern group in the Wakkanai sand lances. The high heterogeneity indicated that the former was probably A. japonicus and the latter probably A. heian. However, the admixture proportion in the Jumunjin and Gijang sand lances was 0.71-0.75 for the southern group, indicating that hybridization and unidirectional introgression from SOL to NOL occurs in southwestern margin of the East Sea. Our findings illustrate the speciation process based on different patterns of gene flow between Korean and Japanese sand lance, which is strongly influenced by both the paleo-climatic change and the contemporary local oceanic current pattern.

Pacific sand lance Ammodytes personatus are a key forage fish in the North Pacific for many species of salmon, groundfish, seabirds, and marine mammals and have historically been important to predators in relatively warm years. However, extreme declines in the nutritional value of sand lance in Prince William Sound, Alaska, USA, during 2012–2016 indicate that energy transfer from lower trophic levels to predators via sand lance may have been disrupted during the North Pacific marine heatwave in 2015 and 2016. Nutritional value (length, energy density, and whole-body energy) was measured in age-0 and age-1 sand lance collected during July in cool (2012–2013) and increasingly warm (2014–2016) years. The value of age-0 fish was relatively stable, with only minor differences among years for length and whole-body energy. By contrast, the value of age-1 fish significantly declined in 2015, and by 2016 they were 38% shorter and 13% lower in energy density compared to cooler years. This contributed to significant declines in whole-body energy of 44% in 2015 and 89% in 2016 compared to cooler years (2012–2014). The 2015 sand lance cohort experienced little growth or lipid accumulation from July 2015 at age-0 to July 2016 at age-1. This effective disruption of energy flow through pelagic food webs probably contributed to population declines and/or breeding failures observed among several predators in the Gulf of Alaska and suggests that tipping points were reached during the heatwave.