bluuebunny/crossref_metadata_2025 huggingface dataset:
Sub-23 nm Solid Particle Number Emission Characteristics for a Heavy-duty Engine Fuelled with Compression Natural Gas
Authors: Wang Xiaowei , Zhang Lin , Wang Mingda , Jing Xiaojun , Gu Xuejing
Published: December 2021

Cold and hot WHTC (World harmonized Transient-State Cycle) were separately run on the engine test bed for a heavy-duty natural gas engine fuelled with high calorific value natural gas and low calorific value natural gas. The particle emissions including PN10 (number of particles above 10nm) and PN23 (number of particles above 23nm) were measured. The results show that the transient emission of PN10 and PN23 have basically the same trends. The weighted specific emission of PN10 is 21.6 times of PN23. Cold start PN emissions account for a relatively large proportion. Fuel property has a great influence on the PN emissions of natural gas engines. The increase of carbon-containing fuels such as methane and ethane in the fuel gas will lead to a rapid increase in PN emissions especially in the cold start process. It is extremely important to strengthen the control of sub-23nm particulate emissions for heavy-duty natural gas engines.
Evaluation of main factors affecting fractured horizontal well productivity of tight sand gas reservoir in Sichuan Basin
Authors: Liu Linqing , Zhai Shuo , Li HaiTao , Wang Jing
Published: December 2021

Hydraulic fracturing horizontal well is the key technology of tight gas development. After fracturing, the gas well shows the characteristics of great difference in production energy and many factors affecting production capacity. Therefore, taking 10 fractured horizontal wells in JQ gas field in Sichuan Basin as an example, comprehensively considering the influence of geological and engineering factors, and based on the statistical analysis of gas well productivity and the laws of various index parameters, 17 geological and engineering parameters were selected, and the main factors controlling productivity were studied by grey correlation method. The results show that the tight gas fracturing horizontal well can obtain high production, which is jointly determined by geological and engineering factors. The five main control factors affecting the productivity of tight gas fracturing horizontal well are as follows: proppant type, preflush, ϕ·h. Sand volume and reservoir volume.
Review on Environmental Treatment of Heavy Pollution Industry
Authors: Chen Jing , Mu Xiaoxue
Published: December 2021

The development of heavy pollution industry has a certain impact on the ecological environment. This paper combs and summarizes the environmental treatment technology of heavy pollution industry from the aspects of air pollution and water pollution. During studing the advantages and disadvantages of various environmental treatment technologies, the authors finds that there are the following problems in the development of environmental treatment technology of heavy pollution industry in China: there is a lack of long-term planning for air pollution environmental treatment; The cost of water pollution control is high and the energy consumption is large. Therefore, relevant environmental governance departments should promote the concept of sustainable development and strengthen the constraints of waste gas and sewage treatment process; Enterprises in heavy pollution industries need to learn and learn from the cutting-edge technologies of environmental governance; Social media positively guide enterprises in heavily polluting industries to protect the ecological environment through public supervision.
Characteristics Analysis and Corrosion Inhibition in Typical Produced Water of Jidong Oilfield
Authors: Dong Chen
Published: December 2021

The composition of oilfield water is complex and diverse. The development and application of corrosion inhibitors can effectively inhibit the corrosion of pipelines and equipment by oilfield water. The ions in produced water of Jidong Oilfield were determined by instrumental analysis and chemical analysis. Triazine prepared from ethanolamine and formaldehyde as corrosion inhibitor was evaluated by weight loss method. The corrosion inhibition experiments were carried out in ancient water samples, and the effects of concentration and temperature on corrosion inhibition were investigated. Finally, corrosion inhibitors were applied to the corrosion inhibition of produced water with different compositions in Jidong Oilfield, the corrosion inhibition of steel sheet was evaluated under different salinity conditions, and the effects of various ion contents in typical water samples and salinity on corrosion inhibition were analyzed. The experimental results show that the corrosion inhibition effect of triazine is better, and the product can be used in various water samples in oilfield with the inhibition efficiency above 85%.
Cambrian Ordovician sedimentary facies and its evolution in Tadong area
Authors: Hansheng Ding
Published: December 2021

In order to clarify the sedimentary development law under the Cambrian Ordovician regional stratigraphic framework in Tadong area, and lay a theoretical foundation for further oil and gas exploration in the study area. The distribution, characteristics and evolution of main sedimentary facies belts of Cambrian Ordovician are studied by means of drilling core observation, cast thin section identification, logging curve feature analysis, seismic profile and well connection profile. The results show that the Cambrian middle lower Ordovician in Tadong area is equivalent to a second-order sequence and can be further divided into 12 thirdorder sequences. Each third-order sequence is mainly composed of transgressive and highstand tracts. Carbonate platform margin beach facies and Reef (mound) beach complex facies are favorable reservoir development facies belts in this area; Under the regional stratigraphic framework, three types of sedimentary facies can be identified in Cambrian Ordovician, and a total of 10 subfacies are developed; The evolution of sedimentary facies is mainly controlled by the rise and fall of sea level, which is characterized by the migration of platform margin facies and the change of platform facies.
Fine evaluation and favorable area prediction of deep source rocks in northern Songliao Basin
Authors: Zhang Fan , Li Yanjie , Ji Xiaoshan , Huo Qiuli , Wu Yuming , Wang Yitong , Ren Zhigao , Bao Junchi
Published: December 2021

Focusing on Xujiaweizi fault depression, the geological conditions and geochemical characteristics of deep natural gas formation in the north of Songliao basin are evaluated, the natural gas resources are estimated, and the favorable areas are optimized. Shahezi Formation shale is a set of coal bearing sediments with high organic matter abundance (TOC is 1%～12%), high over maturity (Ro is 1%～4%) and shore shallow lake facies, which are mainly distributed in Xujiaweizi fault depression, Gulong-Lindian fault depression and Yingshan fault depression. The thickness, TOC, Ro and hydrocarbon generation of four thirdorder sequences with different lithology (mudstone and coal) are carefully evaluated for the Shahezi Formation shale in the deep layer of Songbei. The comprehensive evaluation shows that the mudstone thickness of Es4 member in Anda and Xuzhong areas of Xujiaweizi fault depression is large (150 ~ 525m), TOC is high (1% ~ 4%), thermal evolution degree is high (Ro is 1.2% ~ 3.4%), and gas generation intensity is high (20 ~ 815) × 108m3 / t), moderate buried depth (3000~4500m) and overlapping area of 756km2. It is a favorable exploration area for natural gas and shale gas in Daqing Oilfield.
Analysis of Leakage Cause of L415M Spiral Submerged Arc Welding Pipe
Authors: Xu Yan , Liu Yinglai , Nie Xianghui , Feng Zhenjun , Li Liang , Yang Fengping
Published: December 2021

The causes of longitudinal crack in gas pipeline during pressure were analyzed by means of mechanical property test, microstructure analysis, sem analysis and energy spectrum analysis. The results show that the leakage of L415M spiral submerged arc welded pipe is caused by the contact between the base material of steel pipe and low-melting copper alloy in the process of high temperature, resulting in the brittleness of liquid metal. Specifically, when the leakage site of the steel pipe is heated at an abnormal high temperature, copper penetration along the grain boundary causes embrittlement, strength reduction and crack along the grain boundary, finally leading to the crack and leak of the steel pipe.
Research on the Output Characteristics of Emerging Market Entities Serving the Development of New Energy
Authors: Yin Shuo , Chen Xing , Chai Zhe , Lu Yao , Zhang Danni
Published: December 2021

The power emerging market entities connected to the grid in a decentralized manner can increase the local new energy consumption rate. Under the background of accelerating the development of new energy, it is urgent to clarify the output characteristics of emerging market entities such as wind power, photovoltaics, energy storage, and electric vehicles to adapt to the development of distributed energy and the progress of power market reform. Major emerging entities contribute to mathematical analysis, promote the transaction design of emerging entities, and promote the rapid and healthy development of new energy.
The effect of global warming to California water cycle
Authors: Yang Yi
Published: December 2021

As global warming, climate variability becomes more and more extreme, and the frequency and intensity of extreme weather events are also increasing. Climate change has changed the hydrological cycle, and its change trend has put forward a severe test for the management of world water resources. Climate change has effects on several components of the water cycle, including precipitation, evapotranspiration, runoff, snow and snow cover, glaciers, and frozen soil. This essay analyses the vulnerability of California's various systems to climate change. California's water cycle model is particularly vulnerable to global climate change. In the past hundred years of California, the average precipitation has decreased with fluctuation; the average temperature has increased; extreme weather phenomena have occurred frequently; the evaporation of the water surface has decreased gradually; the temporal and spatial distribution of runoff has changed greatly; and glaciers have accelerated retreat. California's hydrological cycle is consistent with global water cycle change but also exhibits more complicated regional characteristics, with large spatial differences among watersheds.
Cause analysis of pipeline vibration in natural gas station
Authors: Wu Jia , Kong Shuai , Xia Li , Tang Ping
Published: December 2021

Natural gas station is an important part of the whole natural gas pipeline transmission system, in which the pipeline vibration is a hidden danger that cannot be ignored for the safe operation of the station. In view of the severe vibration of the pipeline in a natural gas station of an enterprise, the vibration acceleration sensors are used to test the vibration of each measuring point under different working conditions, and then the three-dimensional finite element model of the pipeline is established by using numerical simulation software to study its structural characteristics and gas column characteristics. Through the analysis of field test results and simulation results, it is found that there are two main vibration frequencies in the pipeline: 116.75 Hz and 123.0 Hz. The former is caused by the resonance between the gas column frequency and the natural frequency in pipe B; The latter is due to the impact of the gas column force in pipe A on pipe B.
Mathematical models of rock mass affected by high pressure gradients
Authors: Revuzhenko Alexandr , Lavrikov Sergey
Published: December 2021

The authors propose to solve the problems connected with high pressure gradients using a model of a linearly elastic body with a structural parameter. The closed finite difference system of equations is formulated for plain strain deformation conditions. The problem on deformation of rock mass in the vicinity of an underground opening affected by mixed-type gravity-and-tectonic stress field is solved. It is demonstrated that addition of the structure in the solution changes the value of the stress concentration coefficient.
Analysis of combined open-pit and underground mining method for Кuzbass coal deposits
Authors: Fedorin Valeriy , Shakhmatov Vyatcheslav , Opruk Gleb , Kuznetsova Yelena
Published: December 2021

Modern development of coal mining industry in Kuzbass is carried out using advanced mining techniques. Analysis of its geological and technological conditions is performed with respect to the development of advanced technologies in related coal mining methods, developing combined (open-pit and underground) geotechnologies for complex mining of coal deposits.
Digitalization as a tool for solving control problems
Authors: Myshlyaev Leonid , Venger Konstantin , Grachev Vitaliy , Ivushkin Konstantin
Published: December 2021

The article is devoted to the consideration of “digitalization” concept as a tool for solving control problems. The problems of digital twins formation are discussed and two directions for digital models creation are presented. The necessity of using a natural-model approach, methods of natural-mathematical modeling, similarity theory for building digital models is noted.
Modeling of induction motor drive of a mine hoist on the basis of a doubly-fed electric machine
Authors: Ostrovlyanchik Viktor , Popolzin Ivan , Kubarev Vasiliy , Qi Dabin
Published: December 2021

One of the options for the modernization of existing hoist electric drives with a wound-rotor induction motor is its starting according to the scheme of a doubly-fed machine. For this purpose, a frequency converter with an adjustable amplitude, frequency and phase shift of the voltage at its output is connected to the motor rotor. At the same time, the problem of obtaining a mathematical model of both the double fed machine itself and the speed control system based on it is relevant due to the need to take into account the additional supply voltage in the differential equations drawn up in accordance with the Kirchhoff’s law for the stator and rotor windings. The paper proposes a structural diagram for the mathematical model of an induction motor drive of a hoist based on a doubly fed machine.
Monitoring the sustainability of in mine degasification boreholes
Authors: Tailakov Oleg , Saltymakov Evgeny , Kolesnichenko Sergey
Published: December 2021

Effective lengths measurements of boreholes drilled by rotary drilling rigs from mine workings based on the echolocation principle, was implemented. Recommendations for drilling and effective use of geophysical equipment for monitoring the degas boreholes conditions in coal mines were substantiated and formulated.
Determination of roof rock weakening zones in extraction columns based on seismic exploration
Authors: Sokolov Sergei , Kolmakova Anastasiya , Rout Gennady , Sööt Peet-Mati
Published: December 2021

This article highlights the difficulties that arise in coal mining when roof areas have fractures with an opening of up to 0.2 - 0.5 m. Such situations may cause roof collapse. The seismic exploration method used by the authors to assess the geomechanical characteristics of extraction columns is described. The results of work on identification and registration of unstable roof areas are presented.
Structural relaxation in Ag-Ni nanoparticles: atomistic modeling away from equilibrium
Authors: Calvo Florent
Published: December 2021

The out-of-equilibrium structural relaxation of Ag-Ni nanoparticles containing about 1000–3000 atoms was investigated computationally by means of molecular dynamics trajectories in which the temperature is decreased gradually over hundreds of nanoseconds. At low silver concentration of 10–30%, the evolution of chemical ordering in NicoreAgshell nanoparticles with different surface arrangements is found to proceed spontaneously and induce some rounding of the nickel core and its partial recrystallization. Fast cooling of an initially hot metal vapor mixture was also considered, and it is shown to disfavor silver aggregation at the surface. Silver impurities are also occasionally produced but remain rare events under the conditions of our simulations.
Pu multi-recycling scenarios towards a PWR fleet for a stabilization of spent fuel inventories in France
Authors: Courtin Fanny , Laguerre Camille , Miranda Philippe , Chabert Christine , Martin Guillaume
Published: December 2021

Nuclear scenario studies are performed to explore the impact of possible evolutions of nuclear fleets. The nuclear fuel cycle simulation tool COSI, developed by CEA, is used to model these dynamic scenarios and to evaluate them with respect to uranium and plutonium management, fuel reprocessing and waste production. In recent years, scenarios have focused on transitions from the current nuclear French fleet to a deployment of SFR. However, the French Multi-annual Energy Planning has recently postponed the deployment of this technology to the second half of the 21st century. Alternative solutions of plutonium management in PWR are investigated to stabilize total inventories of spent nuclear fuels. The MIX concept is based on homogeneous fuel assemblies where fuel rods are composed of plutonium blended with enriched uranium. In this study, a transition from the current French fleet to an EPR™ fleet is simulated. Two power capacities of the future EPR™ fleet are considered. A progressive deployment of fuel multi-recycling in the EPR™ fleet is implemented to enable stabilization of all spent fuels and plutonium inventories. Natural uranium consumption is also minimized thanks to ERU fuel batches in EPR™. Results are compared with plutonium and uranium mono-recycling in a PWR fleet.
Sommersportler werden auch im Winter gemacht
Authors: Best Norman , Edler Christopher
Published: December 2021

Das Weihnachtsfest grüßt nicht zuletzt im Supermarktregal und das
Schmuddelwetter steht vor der Tür. Beste Zeit um Sie, liebe Leserinnen und
Leser, mit einem kleinen Motivationsschub zu versehen, um ein wenig für die
Gesundheit zu tun. Nachdem wir alle nach dem Sommer hart für die
Weihnachtsmannfigur trainiert und Winterspeck angelegt haben und uns so langsam in
Gemütlichkeit bewegen, wäre es nun an der Zeit, diese ungesunde Art
der Lebensführung hinter uns zu lassen. Der genetisch determinierte Hang zur
Faulheit soll für uns, die sportliche Bewegung als ein Hobby ansehen, keine
Ausrede sein.
The Limitations of FDA Criteria: Inconsistencies with Clinical Practice, Findings, and Adult Criteria as a Barrier to Pediatric Implantation
Authors: Park Lisa R. , Gagnon Erika B. , Brown Kevin D.
Published: December 2021

Children require greater access to sound than adults as they are learning to communicate using hearing and spoken language. Yet when it comes to cochlear implant candidacy, currently approved Food and Drug Administration (FDA) criteria for adults are much less restrictive than those for children, allowing for greater levels of residual hearing and aided speech recognition in adults. Cochlear implant guidelines for children have changed very little in the 30 years since cochlear implants have been approved for pediatrics, and this lack of change has proven to be a barrier to implantation. Using evidence-based practice, centers have been providing off-label implantation for children who fall outside of current FDA criteria, including children with more residual hearing, children with single-side deafness younger than 5 years, and infants with bilateral profound loss younger than 9 months. The purpose of this article is to outline how these restrictions impede access to implants for children and describe the evidence supporting cochlear implantation in children who fall outside of current criteria.
The Importance of Access to Bilateral Hearing through Cochlear Implants in Children
Authors: Gordon Karen A. , Papsin Blake C. , Papaioannou Vicky , Cushing Sharon L.
Published: December 2021

Children with hearing loss require early access to sound in both ears to support their development. In this article, we describe barriers to providing bilateral hearing and developmental consequences of delays during early sensitive periods. Barriers include late identification of hearing loss in one or both ears and delayed access to intervention with hearing devices such as cochlear implants. Effects of delayed bilateral input on the auditory pathways and brain are discussed as well as behavioral effects on speech perception and other developmental outcomes including language and academics. Evidence for these effects has supported an evolution in cochlear implant candidacy in children that was started with unilateral implantation in children with profound deafness bilaterally to bilateral implantation to implantation of children with asymmetric hearing loss including children with single-side deafness. Opportunities to enhance the developmental benefits of bilateral hearing in children with hearing loss are also discussed including efforts to improve binaural/spatial hearing and consideration of concurrent vestibular deficits which are common in children with hearing loss.
Development, Implementation, and User Evaluation of COVID-19 Dashboard in a Third-Level Hospital in Iran
Authors: Fazaeli Somayeh , Khodaveisi Taleb , Vakilzadeh Ali Khorsand , Yousefi Mehdi , Ariafar Atousa , Shokoohizadeh Mohsen , Mohammad-Pour Saeed
Published: December 2021

Introduction The implementation of a dashboard enables managers to make informed and evidence-based decisions through data visualization and graphical presentation of information. This study aimed to design and implement a COVID-19 management dashboard in a third-level hospital in Mashhad, Iran.

Materials and Methods This descriptive developmental applied study was conducted in the second half of 2020 in three stages, using user-centered design methodology in four phases: (1) specification of the application context, (2) specification of requirements, (3) creation of design solutions, and (4) evaluation of designs. Data collection in each phase was performed through holding group discussions with the main users, nominal group techniques, interviews, and questioners. The dashboard prototype for the data display was designed using the Power BI Desktop software. Subsequently, users' comments were obtained using the focus group method and included in the dashboard.

Results In total, 25 indicators related to input, process, and output areas were identified based on the findings of the first stage. Moreover, eight items were introduced by participants as dashboard requirements. The dashboard was developed based on users' feedback and suggestions, such as the use of colors, reception of periodic and specific reports based on key performance indicators, and rearrangement of the components visible on the page. The result of the user satisfaction survey indicated their satisfaction with the developed dashboard.

Conclusion The selection of proper criteria for the implementation of an effective dashboard is critical for the health care organization since they are designed with a high-tech and content-based environment. The dashboard in the present study was a successful combination of clinical and managerial indicators. Future studies should focus on the design and development of dashboards, as well as benchmarking by using data from several hospitals.
2.1 Introduction to CuAAC
Authors: Ort F. F. , Rutjes F. P. J. T.
Published: December 2021

The basic principles of the copper-catalyzed azide–alkyne cycloaddition reaction (CuAAC), widely considered to be the first click reaction, are described. This involves amongst others the concept of click reactions, the mechanism of CuAAC, the synthesis and reactivity of organic azides and acetylenes, an overview of most commonly used copper(I) catalysts and ligands, the properties of 1,2,3-triazoles and their resemblance to amides, and a general overview of the scope and limitations of this reaction.
7 Tetrazine-Based Cycloadditions in Click Chemistry
Authors: Kuba W. , Wilkovitsch M. , Carlson J. C. T. , Mikula H.
Published: December 2021

The spontaneous cycloaddition of tetrazines with a number of different dienophiles has become a powerful tool in chemical biology, in particular for the biocompatible conjugation and modification of (bio)molecules. The exceptional reaction kinetics made these bioorthogonal ligations the methods of choice for time-critical processes at very low concentrations, facilitating controlled molecular transformations in complex environments and even in vivo. The emerging concept of bond-cleavage reactions triggered by tetrazine-based cycloadditions enabled the design of diagnostic and therapeutic strategies. The tetrazine-triggered activation of prodrugs represents the first bioorthogonal reaction performed in humans, marking the beginning of the era of clinical translation of bioorthogonal chemistry. This chapter provides an overview of the synthesis and reactivity of tetrazines, their cycloadditions with various dienophiles, and transformations triggered by these reactions, focusing on reaction mechanisms, kinetics and efficiency, and selected applications.
Nationwide assessment of the mental health of UK Doctoral Researchers
Authors: Hazell Cassie M. , Niven Jeremy E. , Chapman Laura , Roberts Paul E. , Cartwright-Hatton Sam , Valeix Sophie , Berry Clio
Published: December 2021

Doctoral Researchers (DRs) are an important part of the academic community and, after graduating, make substantial social and economic contributions. Despite this importance, DR wellbeing has long been of concern. Recent studies have concluded that DRs may be particularly vulnerable to mental health problems, yet direct comparisons of the prevalence of mental health problems between this population and control groups are lacking. Here, by comparing DRs with educated working controls, we show that DRs report significantly greater anxiety and depression, and that this difference is not explained by a higher rate of pre-existing mental health problems. Moreover, most DRs perceive poor mental health as a ‘normal’ part of the PhD process. Thus, our findings suggest a hazardous impact of PhD study on mental health, with DRs being particularly at risk of developing common mental health problems. This provides an evidence-based mandate for universities and funders to reflect upon practices related to DR training and mental health. Our attention should now be directed towards understanding what factors may explain heightened anxiety and depression among DRs so as to inform preventative measures and interventions.
Radiodynamic therapy promises improving cancer treatment
Authors: Cockshott Anne
Published: December 2021

Combing radiotherapy and photodynamic therapy overcomes current penetration issues and achieves targeted tumor treatment.
Iron-oxide-identifying imaging method based on a wide-energy neutron beam for corrosion inspection in reinforced concrete structures
Authors: Tian Binbin , Wang Sheng , Jing Hantao , Yan Mingfei , Gao Xiaolong , Yang Xiaoyun
Published: December 2021

To prevent potential hazards caused by steel corrosion, there is an increase in demand for non-destructive inspection or monitoring of reinforcing steel corrosion in concrete structures. In this study, an iron-oxide-identifying imaging method is proposed that is based on a neutron resonance transmission imaging technique. According to the correlation analysis of the resonance characteristics of iron and oxygen and the elemental fractions, the iron oxides in the corroded reinforced concrete samples were accurately identified and mapped. The volume identification limit of the rust layer was further analyzed, and it is close to 0.1 mm. For the resonance energies of nuclides Fe-56 and O-16 in the tens and hundreds of keV range, the intensity of neutrons at the corresponding energy is only lower about three orders of magnitude after passing through a 40-cm-thick concrete block. The iron-oxide-identifying imaging method could also obtain a clear image of the iron-oxide distribution inside the 20-cm-thick corroded reinforced concrete sample.
Numerical investigation on thrust efficiency dropping phenomenon of annular expansion–deflection nozzles
Authors: Wang Ge , Chen Lei , Zhou Bocheng , Yang Haiwei , Guan Ben , Wang Genlai
Published: December 2021

The flow patterns in a large-expansion-ratio annular expansion–deflection (ED) nozzle are numerically investigated, focusing on the flow mechanisms underlying the sudden thrust efficiency (η) dropping phenomenon. The objective of the present work is to provide a physical understanding of the ED nozzle flow physics responsible for the nozzle performance variation. The simulations are performed by solving the Reynolds averaged Navier–Stokes equations in combination with the one-equation Spalart–Allmaras turbulence model. The Advection Upstream Splitting Method is used to discretize the convective fluxes, and the second-order central scheme is used to discretize the viscous fluxes. The present investigation demonstrates that two flow mechanisms exist, which can cause the sudden η dropping: one is supersonic flow impingement at the nozzle exit, and the other is the formation of the internal normal shock. The pintle arc radius downstream of the throat plays an important role in determining the size and redirection of the supersonic core flow region, thus influencing the overall nozzle performance. A large radius dimension gives a higher η value at the first rising stage, a large dropping nozzle pressure ratio (NPR), and a large mode transition NPR. Interestingly, a cap shock is proved possible in the current large-expansion-ratio ED nozzle, in which the near-shroud shock acts as the internal shock in the traditional thrust-optimized or parabolic nozzles.
A time-resolved imaging system for the diagnosis of x-ray self-emission in high energy density physics experiments
Authors: Halliday Jack W. D. , Bland Simon N. , Hare Jack. D. , Parker Susan , Suttle Lee G. , Russell Danny R. , Lebedev Sergey V.
Published: December 2021

A diagnostic capable of recording spatially and temporally resolved x-ray self-emission data was developed to characterize experiments on the MAGPIE pulsed-power generator. The diagnostic used two separate imaging systems: a pinhole imaging system with two-dimensional spatial resolution and a slit imaging system with one-dimensional spatial resolution. The two-dimensional imaging system imaged light onto the image plate. The one-dimensional imaging system imaged light onto the same piece of image plate and a linear array of silicon photodiodes. This design allowed the cross-comparison of different images, allowing a picture of the spatial and temporal distribution of x-ray self-emission to be established. The design was tested in a series of pulsed-power-driven magnetic-reconnection experiments.
Growth of young cattle grazing high-moisture winter forages in a temperate environment was not affected by access to drinking water
Authors: Banchero G. , Clariget J. , La Manna A. , Watt L. J. , Milton J. T. B. , Fernandez E. , Zarza R. , Baldi F. , Thomas D. T.
Published: December 2021

Context Early sown, annual ryegrass pastures and winter crops provide a high-quality feed for livestock and also have a high water content during autumn and early winter compared with typical temperate pastures. Aim We hypothesised that beef cattle grazing annual ryegrass or forage oats would not need additional access to drinking water to maintain their intake and growth. Methods In Experiment 1, 48 weaned, castrated male Hereford calves with liveweight 154 kg (±6.7 kg; s.d.) grazed Italian ryegrass at a daily allowance of 4.5 kg dry matter (DM)/100 kg liveweight in two treatments including with or without access to drinking water. In Experiment 2, 60 Hereford steers with liveweight 382 kg (±20.6 kg; s.d.) were offered a daily allowance of 5 kg DM/100 kg liveweight of forage oats in a 2 × 2 factorial design either with or without access to drinking water and with or without sorghum grain silage supplemented at 1% of liveweight. The experiments were analysed as a completely randomised design, with individual pasture plots as the experimental unit. Key results Daily growth rates of calves in the two treatments were similar (P > 0.05); however, calves with access to drinking water consumed 60% more water than did the calves without drinking water (P < 0.001). Access to drinking water had no effect (P > 0.05) on the daily growth rate of steers (P > 0.05); however, the daily growth rate of supplemented steers was 9% higher than that of the unsupplemented steers (P < 0.05). Total water intake was affected by access to drinking water (P < 0.005) but not access to supplementation (P > 0.05). Conclusions Both calves and steers derived no production benefits by having access to drinking water when grazing actively growing annual ryegrass pasture or forage oats. Nevertheless, livestock should be monitored closely so that appropriate interventions can be made if there are changes in the pasture availability or weather. Implications Grazing early sown winter forages by livestock can help circumvent the autumn–winter feed gap and these forages can be utilised more cost-effectively by not having to provide drinking water when the DM content is low.
Circular Flip-Flop Index: quantifying revision stability of forecasts of direction
Authors: Griffiths Deryn , Loveday Nicholas , Price Benjamin , Foley Michael , McKelvie Alistair
Published: December 2021

The Flip-Flop Index, designed to quantify the extent to which a forecast changes from one issue time to the next, is extended to a Circular Flip-Flop Index for use with forecasts of wind direction, swell direction or similar. The index was devised so we could understand the degree of stability in wind direction forecasts. The Circular Flip Flop Index is independent of observations, has a relatively simple definition and does not penalise a sequence of forecasts that show a trend as long as the forecasts stay within a 180° sector. The Circular Flip-Flop Index is interpreted in terms of the impact of changing forecasts on decisions made by users of the forecast. The Circular Flip-Flop Index has been used to compare the stability of sequences of automated forecast guidance to the official Australian Bureau of Meteorology forecasts, which are prepared manually. It is the first objective assessment of the stability of forecasts of direction. The results show that the forecasts of wind direction from the automated forecast guidance, itself a consensus of many numerical weather models, are more stable than the official, manual forecasts. The Circular Flip-Flop Index does not measure skill but can play a complementary role in characterising and evaluating a forecasting system.
Changes in photosynthesis and chlorophyll
Authors: Greer Dennis H.
Published: December 2021

Harvesting fruit from horticultural species causes a down-regulation of photosynthesis but some species can recover after harvest. The objective of this study was to assess the hypothesis that the impact of fruit removal on the photosynthetic performance of Shiraz grapevines, in relation to CO2 concentration and leaf temperature, would contribute to a depreciation in photosynthetic assimilation. To assess this hypothesis, vines that were continuously vegetative were compared with vines that were harvested when fruit were ripe. These fruiting vines had higher rates of CO2-limited photosynthesis at all leaf temperatures compared to vegetative vines before harvest but after, photosynthetic rates were highest in vegetative vines. There were few treatment differences in CO2-saturated photosynthesis before harvest but after, below about 30°C, the harvested vines had higher photosynthesis than the vegetative vines. Maximum rates of ribulose 1,5 bisphosphate (RuBP) carboxylation and regeneration and responses to temperature were unaffected by differences in sink demand but after harvest, maximum rates increased, but markedly more in the vegetative vines, especially at higher temperatures. This conformed to higher photosynthetic rates in the vegetative vines. There were no sink demand effects on chlorophyll a fluorescence, consistent with the evidence that the fruit sink removal probably affected Rubisco activity and performance. The conclusion that sink removal caused a depreciation in photosynthesis was sustained but the temperature had a strong modulating effect through both stomatal and non-stomatal limitations driving the depreciation in assimilation. What was less clear was why assimilation of continuously vegetative vines increased during the harvest time when there were no apparent changes in sink demand.
LinearTurboFold: Linear-time global prediction of conserved structures for RNA homologs with applications to SARS-CoV-2
Authors: Li Sizhen , Zhang He , Zhang Liang , Liu Kaibo , Liu Boxiang , Mathews David H. , Huang Liang
Published: December 2021

Significance

Conserved RNA structures are critical for designing diagnostic and therapeutic tools for many diseases including COVID-19. However, existing algorithms are much too slow to model the global structures of full-length RNA viral genomes. We present LinearTurboFold, a linear-time algorithm that is orders of magnitude faster, making it, to our knowledge, the first method to simultaneously fold and align whole genomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, the longest known RNA virus (∼30 kb). Our work enables unprecedented global structural analysis and captures long-range interactions that are out of reach for existing algorithms but crucial for RNA functions. LinearTurboFold is a general technique for full-length genome studies and can help fight the current and future pandemics.
A cross-linguistic study of emphatic negative coordination
Authors: Salaberri Iker
Published: December 2021

The purpose of this paper is to provide a detailed cross-linguistic analysis of so-called emphatic negative coordination (enc). This kind of clause linkage is illustrated byneitherandnorinShe neither could nor would speak lightly of the accident. On the basis of a 250-language sample, the paper lays out a new typology ofencmeant to gain novel insights. It is shown that languages can combineenctypes, and that contact and borrowing are relevant triggers for the emergence of this sort of clause linkage. The article also reveals that there is considerable variety in the etymological sources and grammaticalization paths ofencmarkers.
Boosted ultraviolet photodetection of AlGaN quantum-disk nanowires via rational surface passivation
Authors: Huang Chen , Liang Fangzhou , Yu Huabin , Tian Meng , Zhang Haochen , Ng Tien Khee , Ooi Boon S , Sun Haiding
Published: December 2021

Self-assembled AlGaN nanowires (NWs) are regarded as promising structures in the pursuit of ultraviolet photodetectors (UV PDs). However, AlGaN NW-based PDs currently suffer from degraded performance partially due to the existence of outstanding surface-related defects/traps as a result of their large surface-to-volume-ratio. Here, we propose an effective passivation approach to suppress such surface states via tetramethyl ammonium hydroxide (TMAH) solution treatment. We successfully demonstrate the fabrication of UV PDs using TMAH-passivated AlGaN quantum-disk NWs and investigate their optical and electrical properties. In particular, the dark current can be significantly reduced by an order of magnitude after surface passivation, thus leading to the improvement of photoresponsivity and detectivity. The underlying mechanism for such a boost can be ascribed to the effective elimination of oxygen-related surface states on the NW surface. Consequently, an AlGaN NW UV PD with a low dark current of 6.22 × 10−9 A, a large responsivity of 0.95 A W−1, and a high detectivity of 6.4 × 1011 Jones has been achieved.
Measurement and interpretation of electrical signals in transient electrical discharges*
Authors: Bilbao Luis , Rodríguez Prieto Gonzalo
Published: December 2021

Electrical discharges in experiments like Exploding Wire, Plasma Focus, or Z-pinch, involve regions where strong transient electrical currents generates magnetic flux variations within the limits of experiment and diagnostics regions. Due to different experimental conditions, time duration of the transient phase may vary from negligible to play an important role in the explanation of the measured signal of the experiment, in which case Faraday’s law of induction cannot be neglected when analyzing the electrical signals. In this work the effects of circuit modeling taking into account Faraday’s law will be discussed for the exploding wire experiment in a more detailed way than previous works.
Effect of density fluctuations on gravitational wave production in first-order phase transitions
Authors: Jinno Ryusuke , Konstandin Thomas , Rubira Henrique , van de Vis Jorinde
Published: December 2021

We study the effect of density perturbations on the process of first-order phase transitions and gravitational wave production in the early Universe. We are mainly interested in how the distribution of nucleated bubbles is affected by fluctuations in the local
temperature.
We find that large-scale density fluctuations (H
* < k
* < β) result in a larger effective bubble size at the time of collision, enhancing the produced amplitude of gravitational waves.
The amplitude of the density fluctuations necessary for this enhancement is 𝒫ζ (k
*) ≳ (β/H
*)-2, and therefore the gravitational wave signal from first-order phase transitions with relatively large β/H
* can be
significantly enhanced by this mechanism even for fluctuations with moderate amplitudes.
Cosmological simulations
of number counts
Authors: Lepori Francesca , Adamek Julian , Durrer Ruth
Published: December 2021

In this paper we present for the first time the angular power spectra C
ℓ(z,z') for number counts from relativistic
N-body simulations. We use the relativistic N-body code gevolution with its exact integration of lightlike geodesics which include all relativistic scalar contributions to the number counts. We compare our non-perturbative numerical results with the results from class using the hmcode approximation for the non-linear matter power spectrum. We find that this simple description is excellent for both, the density and the convergence.
On the other hand, the current implementation of redshift-space distortions in Boltzmann codes is not accurate.
We also find that the largest contribution to the unequal-redshift power spectra is the cross-correlation of the density and the lensing contribution to the number counts, especially for redshift bins that are far apart. Correlating
the number counts with the convergence map we find that the signal is dominated by the lensing-lensing term when the convergence field redshift is not higher than the number counts one, while it is dominated by the density-lensing term in the opposite case.
In the present study, the issue of galaxy bias is deliberately left aside by considering only unbiased samples of matter particles from the simulations.
Comparison of quantum and classical methods for labels and patterns in Restricted Boltzmann Machines
Authors: Dixit Vivek , Koshka Yaroslav , Aldwairi Tamer , Novotny M.A.
Published: December 2021

Classification and data reconstruction using a restricted Boltzmann machine (RBM) is presented. RBM is an energy-based model which assigns low energy values to the configurations of interest. It is a generative model, once trained it can be used to produce samples from the target distribution. The D-Wave 2000Q is a quantum computer which has been used to exploit its quantum effect for machine learning. Bars-and-stripes (BAS) and cybersecurity (ISCX) datasets were used to train RBMs. The weights and biases of trained RBMs were used to map onto the D-Wave. Classification as well as image reconstruction were performed. Classification accuracy of both datasets indicates comparable performance using D-Wave’s adiabatic annealing and classical Gibb’s sampling.
Off-lattice and parallel implementations of the pivot algorithm
Authors: Clisby Nathan , Thanh Chuong Ho Dac
Published: December 2021

The pivot algorithm is the most efficient known method for sampling polymer configurations for self-avoiding walks and related models. Here we introduce two recent improvements to an efficient binary tree implementation of the pivot algorithm: an extension to an off-lattice model, and a parallel implementation.
Three dimensional visualization of simulations of liquids and solids
Authors: Adler Joan , Segal Eden , Zeltyn Grisha
Published: December 2021

Visualization in three dimensions is invaluable for understanding the nature of condensed and fluid systems, but it is not always easy. In nature it is hard to view sample interiors, but on computers it is possible. We describe and contrast two opposite approaches - “smoke” visualization for viewing interiors of liquid samples and interactive WebGL for solids and molecules. Both are extensions of earlier Technion Computational Physics group projects and complement and are interoperable with the recent SimPhoNy Fp7 project. They require only desktop hardware and software accessible to students. Examples and standalone instructions for both are presented, starting with sample creation and concluding with image galleries.
Modeling electron transfer from the barrier in InAs/GaAs quantum dot-well structure
Authors: Filikhin I , Kuzmichev Yu B , Mitic V , Peterson Th. , Vlahovic B
Published: December 2021

We study single electron tunnelling from the barrier in the binary InAs/GaAs quantum structure including quantum well (QW) and quantum dot (QD). The tunneling is described in the terms of localized/delocalized states and their spectral distribution. The modeling is performed by using the phenomenological efective potential approach for InAs/GaAs heterostructures. The results for the two and three-dimensional models are presented. We focus on the efect of QD-QW geometry variations. The relation to the PL experiments is shown.
An Optimal Method for Extracting the Center of Light Stripes
Authors: Pan Shuo , Shao Xinjie
Published: December 2021

A method for extracting the center of the light stripe to effectively reduce the environmental noise is proposed in this paper. The block matching algorithm is adapted to use the global information in the structured light image to group image blocks with similar light stripe structures. The center coordinates of the light stripe in each group of image blocks are extracted by the gray gravity method, and its average value is used as the final center of light stripes in the similar image block, which reduces the influence of random noise on the accuracy of the extraction algorithm.
A Novel Cultural Algorithm based on Particle Swarm Optimization and Whale Optimization Algorithm
Authors: Shen Ya , Zhang Chen , Bai Xu , Zhang ChongQing
Published: December 2021

An ameliorative cultural algorithm (CA) based on particle swarm optimization (PSO) and whale optimization algorithm (WOA) is raised (CA-PSOWOA), so as to conquer the defects of WOA and PSO, such as poor global exploration ability and easy fall into local optimal solution. Firstly, a nonlinear inertia weight strategy is leaded to optimize the PSO and WOA, then CA is introduced to regulate the ability of global exploration and local exploitation of PSO and WOA. By testing on benchmark functions, it is proved that CA-PSOWOA improves the global exploration ability and solution accuracy, and its performance is better than the traditional PSO and WOA, and other algorithms.