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The Isa smelting furnace discharges the matte and slag in the same tapping hole. As a result, an electric furnace needs to clean the slag. In the present study, the copper slag cleaning in an electric furnace, particularly the separation of the matte from the slag during the reduction process, was investigated. For Fe3O4 to FeO, the foaming slag in the melt disappeared when the Fe3O4 content was less than 10%. With the formation of the metallic iron, the foaming slag formed again, hindering the sedimentation of the matte. When the anthracite dosage increased to 2.61%, the copper content in the slag increased to 9.46%. The microstructure of the slag and the existence of the metallic iron found in the slag were analyzed in detail. The results obtained in this study provide a theoretical basis for the reasonable control of the transformation of Fe3O4 during the copper slag cleaning.

The important character of the applied moment with a fixed line of direction as implied in deriving the governing differential equations of LTB for elastic beams, however, is not represented in stating the boundary conditions based on conventional energy approaches. This paper sets out to consider the boundary conditions derived by conventional potentials in order to identify the ignored second-order moments that need to be added for maintaining the initial direction of the applied moment during LTB. By taking into account the non-zero work done by these ignored moments for modifying original potentials, the nonconservative nature of the elastic LTB of beam under external moments is clarified in two aspects — by discovering the path-dependent property of the non-zero work and by demonstrating that only trivial solution of LTB mode is expected from the analytical solution of the governing differential equations. Using the concept of dynamic instability, an analysis procedure combining the numerical solution of an eigen-value problem and the bisection method is proposed to identify the first appearance of imaginary or conjugate complex frequencies and to determine the value of the critical moment. Demonstrative examples are considered for illuminating the elastic LTB behavior using conventional energy methods and revised virtual work equation. It has been found that the critical moments given by conventional potentials are generally not consistent with each other unless the work done by the ignored second-order moments vanishes. However, consistent critical moment, under which the free vibrating amplitude of elastic beam is increased unboundedly with time, can be obtained by the kinetic approach based on any revised virtual work equation, indicating the necessity of considering the nonconservative nature of non-follower applied moment. [ABSTRACT FROM AUTHOR]

With society's rapid progress, there is an increasing need for electricity among individuals, but the prevailing source of electricity is still mainly obtained through the burning of nonrenewable fossil fuels, which are not renewable and pose serious environmental hazards. Lithium-ion batteries are used widely for excellent rechargeable capabilities and high energy density. Recently, researchers have become increasingly interested in transition metal sulfides owing to their cost-effectiveness and remarkable specific capacity. However, their commercialization has been hindered by the expansion of material volume and low electrical conductivity during charging and discharging. We have successfully designed and synthesized MoS2 nanosheets loaded on carbon spheres with a 3D hollow structure starting from SiO2 as a template. Due to the doping of carbon materials and particular 3D hollow structures, the optimal C/MoS2-0.3 hollow nanocomposites exhibit excellent electrochemical performance. Following exposure to over 900 cycles at a 0.5 A g-1 ampere density, the materials exhibited an exceptional 958.50 mAh g-1 reversible capacity, demonstrating their remarkable performance. [ABSTRACT FROM AUTHOR]

Based on the electromagnetic thermal coupling analysis method, the cooling performance of different motor cooling models and the influence of key parameters of the cooling system on the cooling effect of the motor are investigated. First, the losses of various parts of the permanent magnet synchronous motors are obtained through electromagnetic calculations; the analysis results show that the stator core loss, winding copper loss, and eddy current loss of permanent magnets exceed 95% of the total loss of the motor. Second, the cooling performance of the three motor was compared and analyzed. The axial housing liquid cooling and oil spray cooling (Model B) has a better cooling performance and a higher cooling efficiency. Compared with the other two motor models, Model B can reduce the time to reach steady-state temperature by about 81.8%. Then the effects of coolant volume flow rate, coolant inlet temperature, and ambient temperature on the cooling effect of the motor are investigated. The results show that within a certain range, the rate of coolant inlet temperature change is approximately proportional to the internal temperature rise of the motor. The oil spray cooling system of Model B is less affected by ambient temperature and can be used for motor cooling in complex environments. The results of this study can provide a useful guidance for the design of the cooling system and the selection of coolant volume flow rate for oil-cooling motor with hairpin windings. [ABSTRACT FROM AUTHOR]

The aim of this study is exploring the development strategies of ecological agriculture in arid areas through the issue of beet irrigation. Based on the quadratic regression rotation method, a water fertilizer coupling model for film-based sugar beet irrigation was established, reflecting the effects of irrigation water volume, nitrogen fertilizer application amount, and potassium fertilizer application amount on sugar beet yield, and considering the interaction of three factors. The experimental results of 20 experimental fields in Ningxia region, China showed that the three factors affecting sugar beet yield from strong to weak were nitrogen fertilizer application amount, irrigation water amount, and potassium fertilizer application amount. Moreover, there was a strong interaction between irrigation water amount and nitrogen fertilizer application amount on sugar beet yield. Furthermore, based on the results irrigation strategies for sugar beets in arid areas can be provided: during the high-water period, the amount of irrigation water should be appropriately increased and the amount of nitrogen fertilizer applied should be reduced; During the dry season, the amount of irrigation water should be appropriately reduced and the amount of nitrogen fertilizer applied should be increased. [ABSTRACT FROM AUTHOR]

The Jinsha river valley in Yunnan Province is a typical dry and hot area in China. By introducing landscape pattern indices, we conducted a spatio-temporal evaluation of regional ecological security from 2000 to 2020 and quantitatively analyzed the influence of its driving factors. Those results showed that: (1) the indices that could characterized the landscape pattern were Division (DIVISION), Mean of Contiguity (CONTIG_MN), Patch Density (PD), and Area Weighted Mean of Shape (SHAPE_AM). (2) From 2000 to 2020, the regional ecological security resulted from cooperative effects of landscape pattern indices and normalized difference vegetation index (NDVI). In 2000, in addition, ecological security resulted from the effects of water quality indices. (3) In 2000, most areas in Yuanmou, Wuding County, and Dongchuan District were in an unsafe or relatively unsafe state. In 2020, some areas of Yuanmou, Wuding, and Yongsheng County were in an unsafe or relatively unsafe state. (4) From 2000 to 2020, the impact of human activity intensity gradually strengthened. Compared with social and economic driving factors, natural driving factors like rainfall and altitude have a greater impact. Our findings can provide theoretical basis and scientific guidance to formulate regional ecological development strategies. [ABSTRACT FROM AUTHOR]

Elevated cerebral ventricular volume may be associated with dementia risk and progression. A fully-automated technique that agreed highly with radiological readings was used to estimate lateral ventricle volume on MR scans done at baseline in 1997-99 of 377 subjects in the Cardiovascular Health Study (CHS) from the Pittsburgh Center. 327 subjects were normal or diagnosed with mild cognitive impairment (MCI) at baseline and were evaluated 4 years later. Baseline ventricular volume was analyzed in multivariate models with age, gender, education level, presence and incidence of cerebral infarcts, and dementia category (normal, MCI, or dementia) at baseline and follow-up as fixed effects. Ventricular volume at baseline was significantly higher among subjects normal at baseline and demented 4 years later. Age, gender, education level, and dementia progression were significant factors affecting ventricular volume. Ventricular volume was higher in dementia compared to MCI, higher in MCI compared to controls, and higher in Possible-Alzheimer's-disease (AD) dementia compared to Probable-AD. Larger ventricles in healthy subjects may indicate susceptibility to, or progression of, dementia-related pathology. (c) 2006 Elsevier Inc. All rights reserved.

Utilizing a two-stage vertical pump as turbine (TVPAT) is an economically method for constructing small-scale pumping and storage hydropower stations at high head-low discharge sites, such as underground coal mines. The energy dissipation mechanisms in flow passages are theoretically important for performance prediction and geometric parameter optimization. In this paper, the energy dissipation within the TVPAT has been studied using entropy generation theory, which can be applied to visual, locate and quantify energy dissipation. The numerical solution of entropy dissipation components was extracted on turbine modes in different flow rates using the steady-state single-phase SST k-ω turbulence model. The numerical results show that the energy dissipation in TVPAT mainly comes from turbulent fluctuation (43.6%-72.1%) and blade surface friction (27.8%-58.2%). The runners are the main source of turbulent entropy (SD') generation (47.2%-83.3%). The contribution of the return channel and spiral case to the SD' generation under overload conditions is significant, accounting for 33.6% and 14.3 at 1.3QBEP, respectively. Flow field analysis reveals that high SD' generation within a runner are located in the striking flow region of the leading edge, the flow squeezing region in the blade channel, and the wake region of tailing edge. The mismatch between the placement angle of the blades or guide vanes and the liquid flow angle is an important incentive for SD' generation. Moreover, hydraulic energy is consumed through the interaction between mainstream and local inferior flows such as separation and vortices, as well as the striking and friction between local fluid and wall surfaces. [ABSTRACT FROM AUTHOR]

The membership of Camelina sativa in the Brassicaceae family has generated substantial interest in its potential as a high-value crop for food, feed, and fuel. Despite the critical regulatory roles played by Thaumatin-like proteins (TLPs) in plant growth and development, their presence in C. sativa has not been previously reported. Through a comprehensive analysis of the C. sativa genome, 34 CsTLP genes have been identified. The chromosomal localization and gene duplication of CsTLPs suggest that the expansion of the gene family was significantly influenced by segmental duplication, while the evolution of CsTLPs was primarily driven by purification selection. Synteny analysis indicates that C. sativa shares a greater number of homologous genes with Arabidopsis thaliana. Additionally, RNA-seq analysis suggests that numerous members of the CsTLPs gene family may potentially participate in abiotic stress. Significantly, the expression of the CsTLP29 gene exhibited a remarkable decrease in response to four distinct stress conditions. The comprehensive examination of the CsTLPs gene family suggests that these genes may have a crucial function in the adaptation of C. sativa to stress and establishes a foundation for further exploration of the TLPs gene family in C. sativa. [ABSTRACT FROM AUTHOR]