Superconducting Electronics Research at CSIRO Australia——20 Years after Discovery of HTS

CSIRO has had a long-term research effort in superconductivity, in particular, since the discovery of HTS which promised big prospects. Significant progress has been made in research and development of HTS electronic devices and systems for practical applications such as mineral and exploration as well as some niche applications in emerging science and technology areas. This article presents an overview of the CSIRO research activities in HTS superconducting electronics since 1987, outlining the HTS junction and device technology as well as various application systems develope d by the group.

煤矿充填固碳理论基础与技术构想

在国家“双碳”目标背景下,如何减少煤炭行业的碳排放、实现碳封存已成为亟待解决的难题。煤炭行业作为高碳化石能源生产者和主体碳排放源提供者,在生产和消费过程中引发的大宗固废堆存、大型采空区形成和大量CO_(2)排放是制约煤炭可持续开发利用与绿色健康发展的瓶颈所在。为协同解决二氧化碳封存与矿山固废消纳问题,将大宗固废处置、固废高值化利用、CO_(2)封存、采空区利用有机结合,提出了二氧化碳充填的理念,从碳汇能力评估角度界定了二氧化碳充填的3种类型。具体开展工作包括:①分析了CO_(2)充填料浆输运过程和矿化反应过程涉及到的基础理论,给出了各个过程的数学方程以及碳封存量计算公式,指出了温度、湿度等因素对矿化反应机理、碳封存量和充填体强度的影响规律。②总结了现阶段CO_(2)矿化的工艺方法、主要碱性工业固废的CO_(2)封存能力和CO_(2)矿化强化措施。在此基础上提出了基于直接湿法矿化和间接矿化的2种CO_(2)充填材料制备工艺,满足矿井充填的流动性、凝固特性和强度要求。③针对CO_(2)充填过程中的CO_(2)物理封存问题,提出了窄条带式胶结充填和综采架后胶结充填2种技术路径,前者通过在弱充填条带中构筑多贯通孔隙的充填体CO_(2)物理封存,后者借助充填支架和链式自行充填挡板在长壁工作面采空区中间断构筑充填带,控制顶板垮落,形成CO_(2)物理化学封存空间。④为了评估CO_(2)充填的碳平衡效果,依据全生命周期法界定了CO_(2)充填中碳足迹及碳消纳的计算边界。然后,梳理了CO_(2)充填过程中的碳足迹及碳消纳,分别考虑了CO_(2)的来源、用量、损耗、转化等因素。给出了包括原料运输、充填料浆制备、井下注入与充填等过程中的碳足迹及碳消纳计算方法。研究成果有望降低CO_(2)封存的能耗及成本,对煤炭绿色开采及其可持续开发利用具有深远的意义。

深色有隔内生真菌(DSE)功能和重金属耐性机制研究进展

重金属污染具有滞留时间久、难恢复和难治理等特点,重金属污染土壤修复备受关注。深色有隔内生真菌(Dark septate endophytes,DSE)可与多种植物建立良好的共生关系,其在促进植物生长、与植物联合共生增强植物对重金属的耐性机制及修复重金属污染土壤方面发挥着重要作用。为系统阐述DSE功能及其对重金属耐性机制,本文综述了DSE的结构特征及定植规律,其促进宿主植物生长的作用机制,重点分析了重金属胁迫下DSE的应答机制(吸附螯合、调控基因表达、抗氧化应激和“区室化”作用等),总结了DSE-植物共生体系在修复重金属污染土壤中的应用现状和前景,以期为DSE在重金属污染环境中的应用提供理论参考。

Energy-efficient joint UAV secure communication and 3D trajectory optimization assisted by reconfigurable intelligent surfaces in the presence of eavesdroppers

We consider a scenario where an unmanned aerial vehicle(UAV),a typical unmanned aerial system(UAS),transmits confidential data to a moving ground target in the presence of multiple eavesdroppers.Multiple friendly reconfigurable intelligent surfaces(RISs) help to secure the UAV-target communication and improve the energy efficiency of the UAV.We formulate an optimization problem to minimize the energy consumption of the UAV,subject to the mobility constraint of the UAV and that the achievable secrecy rate at the target is over a given threshold.We present an online planning method following the framework of model predictive control(MPC) to jointly optimize the motion of the UAV and the configurations of the RISs.The effectiveness of the proposed method is validated via computer simulations.

New insights on the high-corrosion resistance of UHP Mg-Ge alloys tested in a simulated physiological environment

UHP Mg-Ge alloys was recently found to provide excellent corrosion resistance.This paper provides new insights on the mechanism of improved corrosion resistance of UHP Mg-Ge alloys in Hanks’solution.The studied UHP Mg-0.5Ge and UHP Mg-1Ge alloys showed superior corrosion resistance compared to UHP Mg and WE43,with the Mg-1Ge exhibiting the best corrosion performance.The exceptional corrosion resistance of the UHP alloy is attributed to(i)Mg_(2)Ge’s ability to suppress cathodic kinetics,(ii)Ge’s capability to accelerate the formation of a highly passive layer,and the(iii)low amounts of corrosion-accelerating impurities.

Combining field data and modeling to better understand maize growth response to phosphorus(P) fertilizer application and soil P dynamics in calcareous soils

We used field experimental data to evaluate the ability of the agricultural production system model (APSIM) to simulate soil P availability,maize biomass and grain yield in response to P fertilizer applications on a fluvo-aquic soil in the North China Plain.Crop and soil data from a 2-year experiment with three P fertilizer application rates(0,75 and 300 kg P_(2)O_(5) ha^(–1)) were used to calibrate the model.Sensitivity analysis was carried out to investigate the influence of APSIM SoilP parameters on the simulated P availability in soil and maize growth.Crop and soil P parameters were then derived by matching or relating the simulation results to observed crop biomass,yield,P uptake and Olsen-P in soil.The re-parameterized model was further validated against 2 years of independent data at the same sites.The re-parameterized model enabled good simulation of the maize leaf area index (LAI),biomass,grain yield,P uptake,and grain P content in response to different levels of P additions against both the calibration and validation datasets.Our results showed that APSIM needs to be re-parameterized for simulation of maize LAI dynamics through modification of leaf size curve and a reduction in the rate of leaf senescence for modern staygreen maize cultivars in China.The P concentration limits (maximum and minimum P concentrations in organs)at different stages also need to be adjusted.Our results further showed a curvilinear relationship between the measured Olsen-P concentration and simulated labile P content,which could facilitate the initialization of APSIM P pools in the NCP with Olsen-P measurements in future studies.It remains difficult to parameterize the APSIM SoilP module due to the conceptual nature of the pools and simplified conceptualization of key P transformation processes.A fundamental understanding still needs to be developed for modelling and predicting the fate of applied P fertilizers in soils with contrasting physical and chemical characteristics.

Molecular Phylogeny, Species Delimitation and Taxonomic Revision of the Australian Spider Wasp Genus Heterodontonyx Haupt, 1935 (Hymenoptera: Pompilidae)

Heterodontonyx (Pompilidae: Pepsinae) is an understudied genus with Australasiandistribution and most species are endemic to Australia. There have recently been sometaxonomic changes involving the genera Heterodontonyx and Cryptocheilus based on molecular and morphological evidence, however, phylogenetic relationships within Heterodontonyx, species delimitation and formal revision have not been conducted. Here, we construct a Maximum Likelihood phylogeny estimate of Heterodontonyx based on ITS1, 5.8S, ITS2 region of 30 samples representing seven Heterodontonyx morphospecies. bPTP species delimitation approach was employed and ultimately the taxonomic revision of the genus was carried out. Phylogenetic analyses strongly support the monophyly of Heterodontonyx and the species delimitation method recognizes eight species among which one new species is identified.

Graphene-calcium carbonate coating to improve the degradation resistance and mechanical integrity of a biodegradable implant

Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body environment.This necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical integrity.In this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(RGO)-calcium carbonate(CaCO_(3))composite coating.Detailed analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.

Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic gradient.Methods: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to climate.Likelihood methods and information theory were used to select the best model.Results: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their maximum.Conclusions: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of the target tree to competition. The modelling approach should be useful in future research to expand our knowledge of how competition modulates forest communities across environmental gradients.

化学钢化前后玻璃表面裂纹扩展的实验比较与数值模拟

本工作对手机超薄盖板玻璃表面裂纹萌生及扩展过程进行了实验比较和数值模拟。结果表明:对于未经化学钢化处理的玻璃,在载荷为9.80 N的情况下,裂纹萌生时间为压痕出现后30 s;而对于化学钢化玻璃,即便在严苛环境条件下,在9.80 N的载荷作用下,缺陷压痕处未发现裂纹。ABAQUS数值模拟结果表明:(1)最大主张应力位于压印缺陷的四角,并沿径向向外扩展;(2)化学钢化玻璃的最大主张应力比未经化学钢化的玻璃低465 MPa。数值模拟得到的最大主张应力位置与实际裂纹萌生位置一致。对玻璃表面裂纹扩展行为的认识有助于高强度超薄盖板玻璃的研发。

梨小食心虫实时荧光定量PCR内参基因的筛选

【目的】本研究旨在探明梨小食心虫Grapholita molesta在不同发育阶段、成虫不同组织以及不同浓度的3种杀虫剂处理后成虫中稳定表达的内参基因,为后续对梨小食心虫目的基因表达的研究奠定基础。【方法】基于梨小食心虫转录组数据筛选10个候选内参基因(β-actin,18S rRNA,β-tubulin,EF-1α,RPL13,RPL32,RSPL40,UBC7,α-tubulin和RPS20);通过实时荧光定量PCR(qRT-PCR)测定候选内参基因在梨小食心虫不同发育阶段(卵、1-5龄幼虫、蛹和成虫)、成虫不同组织(头、前肠、中肠、后肠、脂肪体、马氏管、精巢和卵巢)以及不同浓度的3种杀虫剂(阿维菌素:19.819,72.897和179.663μg/mL;吡虫啉:17.638,163.323和762.986μg/mL以及高效氯氟氰菊酯:33.791,96.123和198.282μg/mL)通过玻璃管药膜法处理后成虫中的表达量;利用geNorm,NormFinder,ΔCt,BestKeeper和RefFinder对10个候选内参基因的表达稳定性进行评价。选择梨小食心虫细胞色素P450基因CYP354A 32进行验证。【结果】结合qRT-PCR结果和软件评价结果表明,梨小食心虫不同发育阶段内参基因表达稳定性从高到低依次为β-tubulin,18S rRNA,EF-1α,RPL13,β-actin,RPS20,UBC7,RPL32,α-tubulin和RSPL40;成虫不同组织内参基因表达稳定性从高到低依次为UBC7,β-tubulin,β-actin,18S rRNA,RSPL40,EF-1α,RPS20,RPL13,RPL32和α-tubulin;不同浓度阿维菌素、吡虫啉和高效氯氟氰菊酯处理后成虫中内参基因表达稳定性从高到低依次为RPS20,RPL13,β-tubulin,β-actin,RPL32,RSPL40,EF-1α,UBC7,α-tubulin和18S rRNA。用所获得的内参基因组合对CYP354 A2表达特性进行的分析结果表明,用β-tubulin,18S rRNA和EF-1α组合作为内参基因时CYP354 A2在高龄幼虫及成虫中表达量较高,用UBC7,β-tubulin和β-actin组合作为内参基因时在成虫精巢和卵巢中有较高表达,且用RPS20,RPL13和β-tubulin组合作为内参基因时不同浓度杀虫剂处理后仅有19.819μg/mL阿维菌素处理时CYP354 A2表达量高于对照,其余浓度杀虫剂处理时CYP354 A2表达量均低于对照。【结论】梨小食心虫不同发育阶段目的基因表达的研究推荐使用β-tubulin,18S rRNA和EF-1α组合作为内参基因;梨小食心虫成虫不同组织目的基因表达的研究推荐使用UBC7,β-tubulin和β-actin组合作为内参基因;不同浓度阿维菌素、吡虫啉和高效氯氟氰菊酯处理梨小食心虫成虫后目的基因表达的研究推荐使用RPS20,RPL13和β-tubulin组合作为内参基因。

碱改性羊毛的聚六亚甲基双胍抗菌整理

分别采用NaOH、NaAlO_(2)、Na_(2)CO_(3)对羊毛织物进行改性,以提高羊毛织物对聚六亚甲基双胍(PHMB)的吸附率。研究表明,分别采用50 mmol/L NaOH、100 mmol/L NaAlO_(2)、100 mmol/L Na_(2)CO_(3)改性的羊毛织能够吸附4.2%、2.5%、2.2%(omf)的PHMB。吸附了PHMB的羊毛织物均能够杀灭99.9%以上的大肠埃希菌。

杀虫剂处理的梨小食心虫转录组测序分析及差异表达解毒酶基因筛选

试验采用药膜法测定阿维菌素、高效氯氟氰菊酯、吡虫啉对梨小食心虫的室内毒性,旨在挖掘与杀虫剂解毒代谢相关基因,为进一步研究梨小食心虫解毒代谢机制奠定基础。根据生物测定结果,分别将3种杀虫剂原药用丙酮稀释至LC_(10)、LC_(30)、LC_(50)浓度,并将健康成虫放入带有杀虫剂薄膜的玻璃瓶24 h,收集存活的成虫,-80℃保存备用。采用Illumina HiSeq 2000进行高通量测序,获得的非重复序列基因(Unigene),使用NCBI比对工具BLAST分别与NR、NT、SWISS-PROT、Pfam、GO、KOG、KEGG数据库进行比对,获得相应的注释信息;进一步采用生物信息学方法筛选差异表达的解毒酶基因。结果表明,从转录组中共获得101873条Unigenes,平均长度为1992 bp,在NR、NT、SWISS-PROT、Pfam、KEGG、KOG、GO数据库比对,分别有57209、39186、43749、46168、46678、42247、27486条Unigene获得注释。阿维菌素、吡虫啉、高效氯氟氰菊酯处理梨小食心虫后差异表达基因分别有825、641、1391个,其中筛选到20个解毒代谢相关基因,包括4个羧酸酯酶基因、5个谷胱甘肽硫转移酶基因和11个细胞色素P450基因。

Shear behavior of intact granite under thermo-mechanical coupling and three-dimensional morphology of shear-formed fractures

The shear failure of intact rock under thermo-mechanical(TM)coupling conditions is common,such as in enhanced geothermal mining and deep mine construction.Under the effect of a continuous engineering disturbance,shear-formed fractures are prone to secondary instability,posing a severe threat to deep engineering.Although numerous studies regarding three-dimensional(3D)morphologies of fracture surfaces have been conducted,the understanding of shear-formed fractures under TM coupling conditions is limited.In this study,direct shear tests of intact granite under various TM coupling conditions were conducted,followed by 3D laser scanning tests of shear-formed fractures.Test results demonstrated that the peak shear strength of intact granite is positively correlated with the normal stress,whereas it is negatively correlated with the temperature.The internal friction angle and cohesion of intact granite significantly decrease with an increase in the temperature.The anisotropy,roughness value,and height of the asperities on the fracture surfaces are reduced as the normal stress increases,whereas their variation trends are the opposite as the temperature increases.The macroscopic failure mode of intact granite under TM coupling conditions is dominated by mixed tensileeshear and shear failures.As the normal stress increases,intragranular fractures are developed ranging from a local to a global distribution,and the macroscopic failure mode of intact granite changes from mixed tensileeshear to shear failure.Finally,3D morphological characteristics of the asperities on the shear-formed fracture surfaces were analyzed,and a quadrangular pyramid conceptual model representing these asperities was proposed and sufficiently verified.

实时高温下花岗岩节理剪切力学性能及节理面损伤特征

花岗岩节理被认为是提升增强型地热系统(EGS)储层渗透性能的研究对象。花岗岩节理长期处于高温环境中,研究实时高温环境下花岗岩节理剪切行为是解决EGS储层渗透性能提升问题的关键和基础。为此,本文借助岩石剪切伺服试验机及力-热-水耦合剪切试验盒开展了实时高温下花岗岩节理直剪试验。结果表明:花岗岩节理抗剪强度及剪切刚度均随温度升高呈连续劣化趋势,主要划分为两个阶段:缓慢降低阶段(30~200℃)和快速降低阶段(200~400℃)。高温加剧了花岗岩节理表面凸体的剪切破坏,导致节理面剪胀变形随温度的升高而逐渐减小,且减小幅度随法向应力的增加而增大。温度与法向应力间的耦合协同作用加剧了花岗岩节理面的损伤,随温度及法向应力的增加(10 MPa、30℃至30 MPa、400℃),花岗岩节理面剪切损伤面积占比增加了21.41%。高温加剧花岗岩节理表面凸体剪断是节理面粗糙度随温度升高而降低的主要原因。

Sustainable Ammonia Synthesis from Nitrogen and Water by One-Step Plasma Catalysis

Sustainable ammonia synthesis at ambient conditions that relies on renewable sources of energy and feedstocks is globally sought to replace the Haber-Bosch process.Here,using nitrogen and water as raw materials,a nonthermal plasma catalysis approach is demonstrated as an effective powerto-chemicals conversion strategy for ammonia production.By sustaining a highly reactive environment,successful plasma-catalytic production of NH_(3) was achieved from the dissociation of N_(2) and H_(2)O under mild conditions.Plasma-induced vibrational excitation is found to decrease the N_(2) and H_(2)O dissociation barriers,with the presence of matched catalysts in the nonthermal plasma discharge reactor contributing significantly to molecular dissociation on the catalyst surface.Density functional theory calculations for the activation energy barrier for the dissociation suggest that ruthenium catalysts supported on magnesium oxide exhibit superior performance over other catalysts in NH_(3) production by lowering the activation energy for the dissociative adsorption of N_(2) down to 1.07 eV.The highest production rate,2.67 mmol gcat.^(-1) h^(-1),was obtained using ruthenium catalyst supported on magnesium oxide.This work highlights the potential of nonthermal plasma catalysis for the activation of renewable sources to serve as a new platform for sustainable ammonia production.

Are yarn quality prediction tools useful in the breeding of high yielding and better fibre quality cotton(Gossypium hirsutum L.)?

Results The population had large variations for lint yield,fibre properties,predicted yarn properties,and composite fibre quality values.Lint yield with all fibre quality traits was not correlated.When the selection was conducted first to keep those with improved fibre quality,and followed for high yields,a large proportion in the resultant populations was the same between selections based on Cottonspec predicted yarn quality and HVI-measured fibre properties.They both exceeded the selection based on FQI and Background The approach of directly testing yarn quality to define fibre quality breeding objectives and progress the selection is attractive but difficult when considering the need for time and labour.The question remains whether yarn prediction tools from textile research can serve as an alternative.In this study,using a dataset from three seasons of field testing recombinant inbred line population,Cottonspec,a software developed by the Commonwealth Scientific and Industrial Research Organisation(CSIRO)for predicting ring spun yarn quality from fibre properties measured by High Volume Instrument(HVI),was used to select improved fibre quality and lint yield in the population.The population was derived from an advanced generation inter-crossing of four CSIRO conventional commercial varieties.The Cottonspec program was able to provide an integrated index of the fibre qualities affecting yarn properties.That was compared with selection based on HVI-measured fibre properties,and two composite fibre quality variables,namely,fibre quality index(FQI),and premium and discount(PD)points.The latter represents the net points of fibre length,strength,and micronaire based on the Premiums and Discounts Schedule used in the market while modified by the inclusion of elongation.PD points.Conclusions The population contained elite segregants with improved yield and fibre properties,and Cottonspec predicted yarn quality is useful to effectively capture these elites.There is a need to further develop yarn quality prediction tools through collaborative efforts with textile mills,to draw better connectedness between fibre and yarn quality.This connection will support the entire cotton value chain research and evolution.

Autonomous UAV 3D trajectory optimization and transmission scheduling for sensor data collection on uneven terrains

This paper considers a time-constrained data collection problem from a network of ground sensors located on uneven terrain by an Unmanned Aerial Vehicle(UAV),a typical Unmanned Aerial System(UAS).The ground sensors harvest renewable energy and are equipped with batteries and data buffers.The ground sensor model takes into account sensor data buffer and battery limitations.An asymptotically globally optimal method of joint UAV 3D trajectory optimization and data transmission schedule is developed.The developed method maximizes the amount of data transmitted to the UAV without losses and too long delays and minimizes the propulsion energy of the UAV.The developed algorithm of optimal trajectory optimization and transmission scheduling is based on dynamic programming.Computer simulations demonstrate the effectiveness of the proposed algorithm.

半自磨机磨矿过程的模拟研究进展

半自磨机(SAG)凭借流程短、易操作和成本低的优势,近年来在一些大型选矿厂的磨矿环节得到了广泛应用。半自磨机磨矿过程由于矿料之间复杂的相互作用而表现出广泛的动力学特性和流体特性。利用工业试验对磨矿过程开展研究成本高且难度大,而模拟方法能够可视化分析矿料运动特点,便于揭示并掌握磨矿过程规律。离散单元法(DEM)、光滑粒子流体动力学(SPH)和计算流体动力学(CFD)是目前主要的半自磨机磨矿过程研究方法。介绍了三种方法的基本原理及模型耦合过程,对比并总结了不同方法的适用性。在此基础上重点回顾了不同模拟方法对半自磨机磨矿过程中矿料运动状态和衬板磨损及优化两个方面的研究进展,并展望了未来可能的研究方向。

The Black-winged Monarch(Monarcha frater):Geographic variation,taxonomy,a"new"population,and an enduring mystery in migration

The Black-winged Monarch(Monarcha frater)inhabits low-mid elevation forests across New Guinea and far northeastern Australia.Of its four recognized subspecies,M.f.canescens is migratory,breeding in tropical north-eastern Australia from approximately November–March.The non-breeding range of M.f.canescens,apart from some individuals overwintering in Australia,has been unknown for>100 years.Data from 194 New Guinean and Australian specimens and a literature review have not solved this mystery;the narrow latitudinal range of the intratropical migration may inhibit use of GPS loggers in resolving the migration route.Field work in central and western parts of southern New Guinea is needed.Specimen data,however,revealed an essentially overlooked population in north-western New Guinea east of the Bird's Head Peninsula phenotypically indistinguishable from nominate M.f.frater of that Peninsula.Future genomic analysis of the complex will be largely done from toepad skin because frozen tissue samples for DNA analysis exist only of four individuals of what we suggest should be elevated to species rank as M.periophthalmicus.We discuss how genomic analysis might distinguish among alternative taxonomic hypotheses of one,two or three species.We suggest English names for what we consider to be three diagnosable taxa worth recognizing at species rank in this group:Arfak Monarch corresponding to M.frater(Bird's Head Peninsula and the“new”population of north-western New Guinea);Pearly Monarch for M.canescens(Australia and still unknown non-breeding range),and Masked Monarch for M.periophthalmicus(including kunupi,elsewhere in New Guinea).