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Arbuscular mycorrhizal fungi regulate plant mineral nutrient uptake and partitioning in iron ore tailings undergoing eco-engineered pedogenesis

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Pedosphere 2024年第2期34卷 385-398页

作者： Zhen LI Songlin WU Yunjia LIU Qing YI Merinda hall Narottam SAHA Junjian WANG Yuanfang HUANG Longbin HUANG College of Land Science and Technology China Agricultural UniversityBeijing 100193China Centre for Mined Land rehabilitation Sustainable Minerals InstituteThe University of QueenslandBrisbaneQLD 4072Australia Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China

Excess available K and Fe in Fe ore tailings with organic matter amendment and water-deficiencies may restrain plant colonization and growth,which hinders the formation of eco-engineered soil from these tailings for sustainable and cost-effective mine site *** mycorrhizal(AM)fungi are widely demonstrated to assist plant growth under various unfavorable ***,it is still unclear whether AM symbiosis in tailings amended with different types of plant biomass and under different water conditions could overcome the surplus K and Fe stress for plants in Fe ore tailings,and if so,by what ***,host plants(Sorghum *** ***),either colonized or noncolonized by the AM fungi(Glomus spp.),were cultivated in lucerne hay(LH,C:N ratio of 18)-or sugarcane mulch(SM,C:N ratio of 78)-amended Fe ore tailings under well-watered(55%water-holding capacity(WHC)of tailings)or water-deficient(30%WHC of tailings)*** mycorrhizal colonization,plant growth,and mineral elemental uptake and partitioning were *** indicated that AM fungal colonization improved plant growth in tailings amended with plant biomass under water-deficient *** mycorrhizal fungal colonization enhanced plant mineral element uptake,especially P,both in the LH-and SM-amended tailings regardless of water ***,AM symbiosis development restrained the translocation of excess elements(i.e.,K and Fe)from plant roots to shoots,thereby relieving their *** AM fungal roles in P uptake and excess elemental partitioning were greater in LH-amended tailings than in SM-amended *** deficiency weakened AM fungal colonization and functions in terms of mineral element uptake and *** findings highlighted the vital role AM fungi played in regulating plant growth and nutrition status in Fe ore tailings technosol,providing an important basis for involvement of AM fungi in the eco-engineered pedo

关键词： Fe stress fungal symbiosis K stress mine site rehabilitation mycorrhizal colonization plant biomass amendment plant nutrition water deficiency

Stable Isotopic Signatures of NO₃ in Waste Water Effluent and Los Angeles river

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Journal of Water resource and Protection 2024年第1期16卷 102-122页

作者： Isaac hall Mohammad Hassan rezaie Boroon Department of Geography Geology and Environment California State University Los Angeles California USA

A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary treatment before discharging into the LA river. We will gain a better understanding of the water quality in the LA river and the nitrate load in the watershed system by examining the influence of waste water treatment plants (WWTPs). The goal of this study is to pinpoint the exact source of nitrate in the LA river using the isotope signatures. We have selected sampling locations both upstream and downstream of the WWTP. This serves to monitor nitrate levels, aiding in the assessment of treatment plant effectiveness, pinpointing nitrate pollution sources, and ensuring compliance with environmental regulations. The research explores the isotopic composition of NO3 in relation to atmospheric nitrogen and Vienna Standard Mean Ocean Water, shedding light on the contributions from various sources such as manure, sewage, soil organic nitrogen, and nitrogen fertilizers. Specifically, there is a change in the δ15NAir value between the dry and wet seasons. The isotope values in the Tillman WWTP sample changed between dry and wet seasons. Notably, the presence of nitrate originating from manure and sewage is consistent across seasons, emphasizing the significant impact of anthropogenic and agricultural activities on water quality. This investigation contributes to the broader understanding of nitrogen cycling in urban water bodies, particularly in the context of wastewater effluent discharge. The findings hold implications for water quality management and highlight the need for targeted interventions to mitigate the impact of nitrogen-containing compounds on aquatic ecosystems. Overall, the study provides a valuable framework for future research and environmental stewardship efforts aimed at preserving the health and sustainability of urban water resources. This

关键词： Metropolitan City Los Angeles Treatment Plants Sewage Treatment Nitrate Source Isotope Signatures Water Quality

SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.J.hall O.Hetherington T.W.Buggey T.Arnold M.W.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCD370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCDs have been characterised,the two flight devices and the flight spa *** has been carried out at the Open University in a bespo ke cleanroom measure ment *** results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe *** at the nominal ope rating tempe rature(-120℃) it is within the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades with temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SMILE

Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CNT-Infused Orange Peel Biodiesel-Diesel Blend Fuel

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Journal of Thermal Science 2024年第2期33卷 761-778页

作者： ranjeet rAI r.r.SAHOO Mechanical Engineering Department GLA UniversityMathura281406India Mechanical Engineering Department IIT(BHU)Varanasi221005India

The current study is performed to find sustainable solutions for the future of transportation and environmental *** conventional methods and experimental design table(L16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant *** L16 Orthogonal Array is obtained through Taguchi's experimental design approach using Minitab 16 *** experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four *** operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(NO),and smoke emissions,were acquired using the L16 orthogonal array(OA) and subsequently *** utilization of methodologies such as signal-to-noise(S/N) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing *** engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CNT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,*** 25% engine load,1000 r/min,and OPB20CNT100 fuel(A1-B1-C4) CO,smoke,NO,and HC emissions were the *** load affects emissions the *** BSFC increased 3.10% and NO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel *** study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant *** outcomes revealed that orange peel biodiesel infused with CNT can replace diesel fuel in a

关键词： Taguchi-Grey method OPB20CNT100 transesterification S/N ratio GrG HC CO and NO

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面向电铲自主装卸的矿用自卸车斗型优化

吉林大学学报（工学版） 2024年第5期54卷 1227-1236页

作者：谭晓丹王勇澎 robert hall 徐天爽黄庆学吉林大学机械与航空航天工程学院长春130022 太原重型机械集团有限公司矿山采掘装备及智能制造国家重点实验室太原030024 南达科他州矿业理工大学采矿工程与管理学院拉皮德城57701 太原理工大学机械与运载工程学院太原030024

针对现有电铲自主装卸功能在料堆重构、环境感知、目标识别等领域存在技术难度的现状,从降低自主装卸作业任务难度的角度出发,本文提出了一种以载荷均衡分布为目标的矿用自卸车斗型优化方法。首先,构建了一种基于差分迭代的装卸后自卸... 详细信息

针对现有电铲自主装卸功能在料堆重构、环境感知、目标识别等领域存在技术难度的现状,从降低自主装卸作业任务难度的角度出发,本文提出了一种以载荷均衡分布为目标的矿用自卸车斗型优化方法。首先,构建了一种基于差分迭代的装卸后自卸车斗内料堆的轮廓重构方法,并对料堆质心位置进行计算;其次,建立并验证了模拟电铲装卸过程的离散元仿真方法;再次,利用离散元仿真实验,研究了不同斗型结构参数对斗内料堆质心位置的影响;最后,以横向载荷均布为目标,以纵向载荷分布、行驶安全性、斗容变化为约束对斗型进行优化。结果表明:优化后的斗型与原斗型相比,在保持装载能力和行驶安全性的前提下,极端装卸位置时的载荷分布均匀性显著提升,并具有更大的合理装卸面积和更高的作业效率。

关键词：机械设计及理论自主装卸矿用自卸车载荷分布斗型优化

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rare Presentation of Meningioma as an External Auditory Canal Mass

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International Journal of Otolaryngology and Head & Neck Surgery 2024年第5期13卷 378-383页

作者： Justin hall Nikitha Jona Crescentia Cho Michele Gandolfi Department of Otolaryngology Atrium Health Wake Forest Baptist Health Winston Salem NC USA Department of Otolaryngology Wake Forest University School of Medicine Winston Salem NC USA

This is a case of a 60-year-old male with a history of prior left middle fossa meningioma that was partially resected with an operative report noting diffuse attachment to the middle fossa floor. Gamma knife was recommended but he never completed this management. He then presented about eight years later with a mass from his left external auditory canal. It was reported that two years prior another surgeon operated on the left ear for a cholesteatoma. CT temporal bone showed complete opacification of left EAC, mastoid bowl, and remaining mastoid air cells. In addition, there were irregular bony/hyperostotic changes seen within the left sphenoid and temporal bone. There was dural thickening within the middle fossa adjacent to the previously described hyperostotic bony changes. A mastoidectomy and excision of mass revealed extensive adhesive tissue throughout the middle ear, and mastoid up to the tegmen. Pathology of the portions that were resected confirmed Grade 1 meningioma. Stereotactic gamma knife radiation was completed to the area to prevent further growth. This case highlights extracranial meningioma that did not have definitive management for prior middle fossa floor meningioma. It also highlights the need to think of less common pathology in the middle ear and external auditory canal.

关键词： Middle Ear Cranial Base Otology/Neurotology

Kinematic analysis of flexible bipedal robotic systems

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 795-818页

作者： r.FAZEL A.M.SHAFEI S.r.NEKOO Department of Mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de Sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving more exact results,it is essential to model the robot links with viscoelastic *** this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of *** most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational *** extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned *** overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

Holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： H r Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

recently, reconsidering the rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. Hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~H^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

The CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.W.J.Hubbard O.Hetherington D.J.hall T.W.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic rays(GCrs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCrs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation