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A new approach for recycling arsenic and tin from low-grade tin middlings using a self-sulfurization roasting
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作者 LI Lei XU Zhi-peng +4 位作者 HE Jun-li XIAO Yang SUN Yi-xuan LEI Yun ZHOU Juan 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3050-3067,共18页
Massive amounts of low-grade tin middlings have been produced from tin tailings,in which arsenic and tin are worthy to be recycled.Owing to high sulfur content in these tin middlings,a novel self-sulfurization roastin... Massive amounts of low-grade tin middlings have been produced from tin tailings,in which arsenic and tin are worthy to be recycled.Owing to high sulfur content in these tin middlings,a novel self-sulfurization roasting was proposed to transform,separate and recover arsenic and tin in this research.There was no extra curing agent to be added,which decreased the formation of pollutant S-containing gas.The self-sulfurization process involved a two-stage roasting of reduction followed by sulfurization.First in reduction roasting,FeAsS decomposed to FeS and As and the As then transformed to As_(4)(g)and As_(4)S_(4)(g),via which the arsenic was separated and recovered.The arsenic content in the first residue could be decreased to 0.72 wt.%.Accompanied with it,the FeS was firstly oxidized to Fe_(1−x)S and then to SO_(2)(g)by the coexisted Fe_(2)O_(3),and finally reduced and combined with the independent Fe_(2)O_(3)to form Fe_(1−x)S.In the followed sulfurization roasting,the Fe_(1−x)S sulfurized SnO_(2)to SnS(g),due to which tin could be recovered and its content in the second residue decreased to 0.01 wt.%.This study provided an efficient method to separate and recover arsenic and tin from low-grade tin middlings. 展开更多
关键词 low-grade tin middlings continuous sulfur transformation self-sulfurization separation of arsenic and tin RECYCLING
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Liberation characteristics of coal middlings comminuted by jaw crusher and ball mill 被引量:12
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作者 Xie Weining He Yaqun +3 位作者 Zhu Xiangnan Ge Linhan Huang Yajun Wang Haifeng 《International Journal of Mining Science and Technology》 SCIE EI 2013年第5期669-674,共6页
The associated minerals make coal middlings possess a relatively high ash content.Subsequent liberation through size reduction can cause recovery increase.However,effect of comminution facilities on mineral liberation... The associated minerals make coal middlings possess a relatively high ash content.Subsequent liberation through size reduction can cause recovery increase.However,effect of comminution facilities on mineral liberation of middlings was ignored.This paper studied the liberation characteristics of middlings crushed with different kinds of fragmentation forces.Middlings of 3 mm+0.5 mm sampled from a dense medium cyclone were comminuted by a jaw crusher and a ball mill to 0.5 mm with similar size distribution respectively.The generating mechanism of fnes was also analyzed.Full densimetric analyses indicate that mineral liberation of the product crushed by the jaw crusher is better than that by the ball mill at each fraction.For sizes of 0.125 mm+0.074 mm and 0.074 mm,yields of the product with ash content 11%comminuted by jaw crusher are nearly 20%higher than that by the ball mill.Sectional micrographs observed by the scanning electron microscopy(SEM)also show the same law for these two fractions and some intergrowth particles still exist in the fraction of 0.5 mm+0.25 mm. 展开更多
关键词 Coal middlings Fragmentation force LIBERATION Float and sink test Sectional micrograph
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Coal petrology characteristics of middlings from Qianjiaying fat coal mine 被引量:8
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作者 Zou Wenjie Cao Yijun +1 位作者 Zhang Zhijun Liu Jiongtian 《International Journal of Mining Science and Technology》 SCIE EI 2013年第5期777-782,共6页
The objective of this paper is to evaluate the coal petrology characteristics of slack middlings(13–0.5 mm)of dense media separation and flotation middlings from Qianjiaying fat coal preparation plant.Phase compositi... The objective of this paper is to evaluate the coal petrology characteristics of slack middlings(13–0.5 mm)of dense media separation and flotation middlings from Qianjiaying fat coal preparation plant.Phase composition,macerals distribution,microlithotype and mineral occurrence of the two middlings were studied by XRD analysis and polarized light microscopy observation.Macerals distribution and wettability of the float-and-sink products separated from the middlings after grinding was investigated to determine the liberation degree.Studies show that there are more vitrinite and mineral,but less inertinite in slack middlings than in flotation middlings.Macerals associated with mineral in slack middlings is 69.85%,by volume,which is 17.86%higher than that in flotation middlings.Minerals in slack middlings are dominated by pyrite and clay,which are disseminated with the diameter less than2 lm.The main mineral in flotation middlings is clay with size range of 2–20 lm.Single macerals in the slack middlings are diffcult to liberate due to the fne-grained minerals.After grinding,macerals associated with minerals in the slack middlings decrease to 46.73%,by volume,which is higher than in flotation middlings by 25.89%,by volume.For slack middlings with poor liberation degree,density fractions below1.8 g/cm3is hydrophobic with contact angle above 71.5°.For the well liberated flotation middlings,there is signifcant wettability difference among the float-and-sink products.This research is the theoretical basis to realize re-separation of middlings. 展开更多
关键词 middlingS MACERALS Mineral liberation WETTABILITY
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Tin recovery from a low-grade tin middling with high Si content and low Fe content by reduction–sulfurization roasting with anthracite coal 被引量:2
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作者 Jing-cheng Wang Lei Li Yong Yu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第2期210-220,共11页
A new method for separating and recovering tin from a low-grade tin middling with high Si content and low Fe content by roasting with anthracite coal was researched by studying the reaction mechanism and performing an... A new method for separating and recovering tin from a low-grade tin middling with high Si content and low Fe content by roasting with anthracite coal was researched by studying the reaction mechanism and performing an industrial test,in which the Sn was sulfurized into SnS(g)and then collected using a dust collector.The Fe–Sn alloy may be formed at roasting temperatures above 950°C,and like the roasting temperature increases,the Sn content and Sn activity in this Fe–Sn alloy decrease.Also,more FeS can be formed at higher temperatures and then the formation of FeO–FeS with a low melting point is promoted,which results in more serious sintering of this low-grade tin middling.And from the thermodynamics and kinetics points of view,the volatilization of the Sn decreases at extremely high roasting temperatures.The results of the industrial test carried out in a coal-fired rotary kiln show that the Sn volatilization rate reaches 89.7%and the Sn is concentrated in the collected dust at a high level,indicating that the Sn can be effectively extracted and recovered from the low-grade tin middling with a high Si content and low Fe content through a reduction–sulfurization roasting process. 展开更多
关键词 low-grade tin middling tin recovery roasting process Fe-Sn alloy resource recycling
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High-frequency repetitive transcranial magnetic stimulation promotes neural stem cell proliferation after ischemic stroke 被引量:3
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作者 Jing Luo Yuan Feng +4 位作者 Zhongqiu Hong Mingyu Yin Haiqing Zheng Liying Zhang Xiquan Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1772-1780,共9页
Prolife ration of neural stem cells is crucial for promoting neuronal regeneration and repairing cerebral infarction damage.Transcranial magnetic stimulation(TMS)has recently emerged as a tool for inducing endogenous ... Prolife ration of neural stem cells is crucial for promoting neuronal regeneration and repairing cerebral infarction damage.Transcranial magnetic stimulation(TMS)has recently emerged as a tool for inducing endogenous neural stem cell regeneration,but its underlying mechanisms remain unclea r In this study,we found that repetitive TMS effectively promotes the proliferation of oxygen-glucose deprived neural stem cells.Additionally,repetitive TMS reduced the volume of cerebral infa rction in a rat model of ischemic stro ke caused by middle cerebral artery occlusion,im p roved rat cognitive function,and promoted the proliferation of neural stem cells in the ischemic penumbra.RNA-sequencing found that repetitive TMS activated the Wnt signaling pathway in the ischemic penumbra of rats with cerebral ischemia.Furthermore,PCR analysis revealed that repetitive TMS promoted AKT phosphorylation,leading to an increase in mRNA levels of cell cycle-related proteins such as Cdk2 and Cdk4.This effect was also associated with activation of the glycogen synthase kinase 3β/β-catenin signaling pathway,which ultimately promotes the prolife ration of neural stem cells.Subsequently,we validated the effect of repetitive TMS on AKT phosphorylation.We found that repetitive TMS promoted Ca2+influx into neural stem cells by activating the P2 calcium channel/calmodulin pathway,thereby promoting AKT phosphorylation and activating the glycogen synthase kinase 3β/β-catenin pathway.These findings indicate that repetitive TMS can promote the proliferation of endogenous neural stem cells through a Ca2+influx-dependent phosphorylated AKT/glycogen synthase kinase 3β/β-catenin signaling pathway.This study has produced pioneering res ults on the intrinsic mechanism of repetitive TMS to promote neural function recove ry after ischemic stro ke.These results provide a stro ng scientific foundation for the clinical application of repetitive TMS.Moreover,repetitive TMS treatment may not only be an efficient and potential approach to support neurogenesis for further therapeutic applications,but also provide an effective platform for the expansion of neural stem cells. 展开更多
关键词 AKT/β-catenin signaling brain stimulation Ca2+influx cell proliferation ischemic stroke middle cerebral artery occlusion neural stem cells neurological rehabilitation repetitive transcranial magnetic stimulation
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Episodic hydrothermal alteration on Middle Permian carbonate reservoirs and its geological significance in southwestern Sichuan Basin,SW China
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作者 FENG Mingyou SHANG Junxin +5 位作者 SHEN Anjiang WEN Long WANG Xingzhi XU Liang LIANG Feng LIU Xiaohong 《Petroleum Exploration and Development》 SCIE 2024年第1期81-96,共16页
To analyze the episodic alteration of Middle Permian carbonate reservoirs by complex hydrothermal fluid in southwestern Sichuan Basin,petrology,geochemistry,fluid inclusion and U-Pb dating researches are conducted.The... To analyze the episodic alteration of Middle Permian carbonate reservoirs by complex hydrothermal fluid in southwestern Sichuan Basin,petrology,geochemistry,fluid inclusion and U-Pb dating researches are conducted.The fractures and vugs of Middle Permian Qixia–Maokou formations are filled with multi-stage medium-coarse saddle dolomites and associated hydrothermal minerals,which indicates that the early limestone/dolomite episodic alteration was caused by the large-scale,high-temperature,deep magnesium-rich brine along flowing channels such as basement faults or associated fractures under the tectonic compression and napping during the Indosinian.The time of magnesium-rich hydrothermal activity was from the Middle Triassic to the Late Triassic.The siliceous and calcite fillings were triggered by hydrothermal alteration in the Middle and Late Yanshanian Movement and Himalayan Movement.Hydrothermal dolomitization is controlled by fault,hydrothermal property,flowing channel and surrounding rock lithology,which occur as equilibrium effect of porosity and permeability.The thick massive grainstone/dolomites were mainly altered by modification such as hydrothermal dolomitization/recrystallization,brecciation and fracture-vugs filling.Early thin-medium packstones were mainly altered by dissolution and infilling of fracturing,bedding dolomitization,dissolution and associated mineral fillings.The dissolved vugs and fractures are the main reservoir space under hydrothermal conditions,and the connection of dissolved vugs and network fractures is favorable for forming high-quality dolomite reservoir.Hydrothermal dolomite reservoirs are developed within a range of 1 km near faults,with a thickness of 30–60 m.Hydrothermal dolomite reservoirs with local connected pore/vugs and fractures have exploration potential. 展开更多
关键词 Sichuan Basin PERMIAN Middle Permian Qixia Formation Middle Permian Maokou Formation hydrothermal fluid hydrothermal dissolution DOLOMITE
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Middle hepatic vein variation provides a safe path for anterior transection of hepatocellular carcinoma in caudate lobe
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作者 Bing-Yi Lin Qi-Jun Zhang +1 位作者 Zhe Yang Shu-Sen Zheng 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第4期438-440,共3页
To the Editor:Hepatocellular carcinoma(HCC)is one of the main causes of cancer related death worldwide,and new cases are expected to continue to increase in future[1].Surgical resection is still the best way to remove... To the Editor:Hepatocellular carcinoma(HCC)is one of the main causes of cancer related death worldwide,and new cases are expected to continue to increase in future[1].Surgical resection is still the best way to remove the tumor and improve patient’s prognosis.However,resection of caudate lobe often presents a technical challenge,even to accomplished hepatic surgeons.Caudate lobe is located anterior to the inferior vena cava(IVC)and posterior to the bifurcation of the portal vein(PV),generally consists of three regions:the paracaval portion,the left Spiegel lobe and the process portion[2].The anatomy of the paracaval portion includes the liver parenchyma ventral to the hepatic IVC and the area between the Spiegel lobe and the right lobe adjacent to the middle hepatic vein(MHV)ventrally,which was classified by Couinaud as segment IX[3].Here,we presented a case of HCC with successful downstaging therapy,as well as variation of MHV,which provides a safe path for anterior transection of segment IX. 展开更多
关键词 HEPATIC ANATOMY MIDDLE
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The Middle Miocene lobe-shaped and band-shaped submarine fans in the Lingshui Sag,Qiongdongnan Basin:source-to-sink system,genesis and implication
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作者 Xingzong Yao Congjun Feng +2 位作者 Hongjun Qu Min Zhang Daming Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期61-79,共19页
Deepwater oil and gas exploration is the key to sustainable breakthroughs in petroleum exploration worldwide.The Central Canyon gas field has confirmed the Lingshui Sag is a hydrocarbon-generating sag,and the deepwate... Deepwater oil and gas exploration is the key to sustainable breakthroughs in petroleum exploration worldwide.The Central Canyon gas field has confirmed the Lingshui Sag is a hydrocarbon-generating sag,and the deepwater reservoirs in the Lingshui Sag still have more fabulous oil and gas exploration potential.Based on drilling data and three-dimensional(3D)seismic data,this paper uses seismic facies analysis,seismic attribute analysis,and coherence slice analysis to identify the types of submarine fans(lobe-shaped and band-shaped submarine fans)that developed in the Lingshui Sag during the Middle Miocene,clarify the source-to-sink system of the submarine fans and discuss the genesis mechanism of the submarine fans.The results show that:(1)the deepwater source-to-sink system of the Lingshui Sag in the Middle Miocene mainly consisted of a“delta(sediment supply)-submarine canyon(sediment transport channel)-submarine fan(deepwater sediment sink)”association;(2)the main factor controlling the formation of the submarine fans developed in the Lingshui Sag was on the relative sea level decline;and(3)the bottom current reworked the lobe-shaped submarine fan that developed in the northern Lingshui Sag and formed the band-shaped submarine fan with a greater sand thickness.This paper aims to provide practical geological knowledge for subsequent petroleum exploration and development in the deepwater area of the Qiongdongnan Basin through a detailed analysis of the Middle Miocene submarine fan sedimentary system developed in the Lingshui Sag. 展开更多
关键词 submarine fan source-to-sink system genesis mechanism Middle Miocene Lingshui Sag
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Age and geochemical evolution of granite magmatism in Olkhon region from Caledonian syncollisional ore-free granite to the rare metal granite and pegmatite of Middle Paleozoic intraplate setting
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作者 Viktor Antipin Valentina Makrygina +1 位作者 Larisa Kushch Nataliya Sheptyakova 《China Geology》 CAS CSCD 2024年第1期63-79,共17页
The detailed description of two granite complexes in the Olkhon subterrane is given.The Early Paleozoic Sharanur complex was formed by granitization of gneisses of the Olkhon series.It includes migmatites,granite-gnei... The detailed description of two granite complexes in the Olkhon subterrane is given.The Early Paleozoic Sharanur complex was formed by granitization of gneisses of the Olkhon series.It includes migmatites,granite-gneisses,granites and pegmatites of normal alkalinity;they belong to the type of syncollisional granites.The Middle Paleozoic Aya granite complex includes mother Aya massif of amazonite-bearing granites and several types of rare-metal pegmatites.They have elevated alkalinity,low of Ba,Sr,and high LILE and HFSE elements contents.The Aya pegmatites lie in northwest cracks of stretching and associated with the rise of the territory under the influence of the North Asian plume.These cracks and pegmatites mark the beginning of a new intraplate geodynamic setting.Two geochemical types are distinguished among the pegmatites of this complex.These are amazonite pegmatites of Li-F type with Ta mineralization and complex type pegmatite with Be-Rb-Nb-Ta and Li-F mineralization(the Ilixin vein).The Tashkiney pegmatite vein is similar to Ilixin,but lies in the gneisses of the Olkhon series.It shows high concentrations of Be,Nb,Ta,as well as W,Sn,but lacks Li and F,due to a greater depth and higher temperature of the melt crystallization of this pegmatite. 展开更多
关键词 PEGMATITE Geochemistry Submantle plume MAGMATISM Caledonian collision Middle Paleozoic intraplate setting Be-Rb-Nb-Ta-Li-F mineralization Olkhon region Russia
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Coral records of Mid-Holocene sea-level highstands and climate responses in the northern South China Sea
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作者 Yuanfu Yue Lichao Tang +1 位作者 Kefu Yu Rongyong Huang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期43-57,共15页
High-resolution sea-level data and high-precision dating of corals in the northern South China Sea(SCS)during the Holocene provide a reference and historical background for current and future sea-level changes and a b... High-resolution sea-level data and high-precision dating of corals in the northern South China Sea(SCS)during the Holocene provide a reference and historical background for current and future sea-level changes and a basis for scientific assessment of the evolutionary trend of coral reefs in the SCS.Although sporadic studies have been performed around Hainan Island in the northern SCS,the reconstructed sea level presents different values or is controversial because the indicative meaning of the sea-level indicators were neither quantified nor uniform criteria.Here,we determined the quantitative relationship between modern living coral and sea level by measuring the top surfaces of 27 live Porites corals from the inner reef flat along the east coast of Hainan Island and assessed the accuracy of results obtained using coral as sea-level indicators.Additionally,three in situ fossil Porites corals were analyzed based on elevation measurements,digital X-ray radiography,and U-Th dating.The survey results showed that the indicative meanings for the modern live Porites corals is(146.09±8.35)cm below the mean tide level(MTL).It suggested that their upward growth limit is constrained by the sea level,and the lowest low water is the highest level of survival for the modern live Porites corals.Based on the newly defined indicative meanings,6 new sea-level index points(SLIPs)were obtained and 19 published SLIPs were recalculated.Those SLIPs indicated a relative sea level fluctuation between(227.7±9.8)cm to(154.88±9.8)cm MTL between(5393±25)cal a BP and(3390±12)cal a BP,providing evidences of the Mid-Holocene sea-level highstand in the northern SCS.Besides that,our analysis demonstrated that different sea-level histories may be produced based on different indicative meanings or criteria.The dataset of 276 coral U-Th ages indicates that coral reef development in the northern SCS comprised the initial development,boom growth,decline,and flourishing development again.A comparison with regional records indicated that synergistic effects of climatic and environmental factors were involved in the development of coral reefs in the northern SCS.Thus,the cessation of coral reef development during the Holocene in the northern SCS was probably associated with the dry and cold climate in South China,as reflected in the synchronous weakening of the ENSO and East Asian summer monsoon induced by the reduction of the 65°N summer insolation,which forced the migration of the Intertropical Convergence Zone. 展开更多
关键词 northern South China Sea Middle Holocene sea-level highstand Porites corals climate response
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Characteristics and main controlling factors of intra-platform shoal thin-layer dolomite reservoirs:A case study of Middle Permian Qixia Formation in Gaoshiti-Moxi area of Sichuan Basin,SW China
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作者 HE Jiang LIAN Zhihua +5 位作者 LUO Wenjun ZHOU Hui XU Huilin HE Puwei Yang Yi LAN Xuemei 《Petroleum Exploration and Development》 SCIE 2024年第1期69-80,共12页
Based on the study of the distribution of intra-platform shoals and the characteristics of dolomite reservoirs in the Middle Permian Qixia Formation in the Gaoshiti–Moxi area of the Sichuan Basin,SW China,the control... Based on the study of the distribution of intra-platform shoals and the characteristics of dolomite reservoirs in the Middle Permian Qixia Formation in the Gaoshiti–Moxi area of the Sichuan Basin,SW China,the controlling factors of reservoir development were analyzed,and the formation model of“intra-platform shoal thin-layer dolomite reservoir”was established.The Qixia Formation is a regressive cycle from bottom to top,in which the first member(Qi1 Member)develops low-energy open sea microfacies,and the second member(Qi2 Member)evolves into intra-platform shoal and inter-shoal sea with decreases in sea level.The intra-platform shoal is mainly distributed near the top of two secondary shallowing cycles of the Qi2 Member.The most important reservoir rock of the Qixia Formation is thin-layer fractured-vuggy dolomite,followed by vuggy dolomite.The semi-filled saddle dolomite is common in fracture-vug,and intercrystalline pores and residual dissolution pores combined with fractures to form the effective pore-fracture network.Based on the coupling analysis of sedimentary and diagenesis characteristics,the reservoir formation model of“pre-depositional micro-paleogeomorphology controlling shoal,sedimentary shoal controlling dolomite,penecontemporaneous dolomite benefiting preservation of pores,and late hydrothermal action effectively improving reservoir quality”was systematically established.The“first-order high zone”micro-paleogeomorphology before the deposition of the Qixia Formation controlled the development of large area of intra-platform shoals in Gaoshiti area during the deposition of the Qi2 Member.Shoal facies is the basic condition of early dolomitization,and the distribution range of intra-platform shoal and dolomite reservoir is highly consistent.The grain limestone of shoal facies is transformed by two stages of dolomitization.The penecontemporaneous dolomitization is conducive to the preservation of primary pores and secondary dissolved pores.The burial hydrothermal fluid enters the early dolomite body along the fractures associated with the Emeishan basalt event,makes it recrystallized into medium–coarse crystal dolomite.With the intercrystalline pores and the residual vugs after the hydrothermal dissolution along the fractures,the high-quality intra-platform shoal-type thin-layer dolomite reservoirs are formed.The establishment of this reservoir formation model can provide important theoretical support for the sustainable development of Permian gas reservoirs in the Sichuan Basin. 展开更多
关键词 Middle Permian Qixia Formation intra-platform shoal thin-layer dolomite paleogeomorphology diagenesis Gaoshiti-Moxi area Sichuan Basin
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Exercise preconditioning alleviates ischemia-induced memory deficits by increasing circulating adiponectin
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作者 Meifeng Zheng Borui Zhang +3 位作者 Sonata S Y Yau Kwok-Fai So Li Zhang Haining Ou 《Neural Regeneration Research》 SCIE CAS 2025年第5期1445-1454,共10页
Cerebral ischemia is a major health risk that requires preventive approaches in addition to drug therapy.Physical exercise enhances neurogenesis and synaptogenesis,and has been widely used for functional rehabilitatio... Cerebral ischemia is a major health risk that requires preventive approaches in addition to drug therapy.Physical exercise enhances neurogenesis and synaptogenesis,and has been widely used for functional rehabilitation after stroke.In this study,we determined whether exercise training before disease onset can alleviate the severity of cerebral ischemia.We also examined the role of exercise-induced circulating factors in these effects.Adult mice were subjected to 14 days of treadmill exercise training before surgery for middle cerebral artery occlusion.We found that this exercise pre-conditioning strategy effectively attenuated brain infarct area,inhibited gliogenesis,protected synaptic proteins,and improved novel object and spatial memory function.Further analysis showed that circulating adiponectin plays a critical role in these preventive effects of exercise.Agonist activation of adiponectin receptors by Adipo Ron mimicked the effects of exercise,while inhibiting receptor activation abolished the exercise effects.In summary,our results suggest a crucial role of circulating adiponectin in the effects of exercise pre-conditioning in protecting against cerebral ischemia and supporting the health benefits of exercise. 展开更多
关键词 ADIPONECTIN cerebral ischemia exercise pre-conditioning HIPPOCAMPUS memory function middle cerebral artery occlusion prefrontal cortex synaptic proteins treadmill exercise
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Digital Twin Modeling and Simulation Optimization of Transmission Front and Middle Case Assembly Line
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作者 Xianfeng Cao Meihua Yao +2 位作者 Yahui Zhang Xiaofeng Hu Chuanxun Wu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3233-3253,共21页
As the take-off of China’s macro economy,as well as the rapid development of infrastructure construction,real estate industry,and highway logistics transportation industry,the demand for heavy vehicles is increasing ... As the take-off of China’s macro economy,as well as the rapid development of infrastructure construction,real estate industry,and highway logistics transportation industry,the demand for heavy vehicles is increasing rapidly,the competition is becoming increasingly fierce,and the digital transformation of the production line is imminent.As one of themost important components of heavy vehicles,the transmission front andmiddle case assembly lines have a high degree of automation,which can be used as a pilot for the digital transformation of production.To ensure the visualization of digital twins(DT),consistent control logic,and real-time data interaction,this paper proposes an experimental digital twin modeling method for the transmission front and middle case assembly line.Firstly,theDT-based systemarchitecture is designed,and theDT model is created by constructing the visualization model,logic model,and data model of the assembly line.Then,a simulation experiment is carried out in a virtual space to analyze the existing problems in the current assembly line.Eventually,some improvement strategies are proposed and the effectiveness is verified by a new simulation experiment. 展开更多
关键词 Transmission front and middle case assembly line digital twin(DT) simulating optimization intelligent manufacturing
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Construction and Research Progress of the Chinese Meridian Project in 2022–2023
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作者 WANG Chi CHEN Zhiqing XU Jiyao 《空间科学学报》 CAS CSCD 北大核心 2024年第4期704-711,共8页
The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing... The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing the monitoring data collected by the CMP,scientists made major breakthroughs in fields of ionosphere,middle and upper atmosphere,and coupling between layers.The construction of the second phase of the CMP is nearly finished,and the project is expected to operate as a whole in 2025 after national acceptance of the second phase.The whole project was built in an architecture of so-called“One Chain,Three Networks and Four Focuses”.It is promising to make a three-dimensional observation of the whole solar-terrestrial space.The science community is looking forward to the great contribution of the CMP to space weather and space physics research. 展开更多
关键词 Chinese Meridian Project(CMP) MAGNETOSPHERE IONOSPHERE Middle and upper atmosphere
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Separate-layer balanced waterflooding development technology for thick and complex carbonate reservoirs in the Middle East
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作者 SONG Xinmin LI Yong +6 位作者 LI Fengfeng YI Liping SONG Benbiao ZHU Guangya SU Haiyang WEI Liang YANG Chao 《Petroleum Exploration and Development》 SCIE 2024年第3期661-673,共13页
Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic... Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic limestone reservoirs of Cretaceous in Iran-Iraq as an example,this paper proposes a balanced waterflooding development technology for thick and complex carbonate reservoirs.This technology includes the fine division of development units by concealed baffles and barriers,the combination of multi well type and multi well pattern,and the construction of balanced water injection and recovery system.Thick carbonate reservoirs in Iran-Iraq are characterized by extremely vertical heterogeneity,development of multi-genesis ultra-high permeability zones,and highly concealed baffles and barriers.Based on the technologies of identification,characterization,and sealing evaluation for concealed baffles and barriers,the balanced waterflooding development technology is proposed,and three types of balanced waterflooding development modes/techniques are formed,namely,conventional stratigraphic framework,fine stratigraphic framework,and deepened stratigraphic framework.Numerical simulations show that this technology is able to realize a fine and efficient waterflooding development to recover,in a balanced manner,the reserves of thick and complex carbonate reservoirs in Iran and Iraq.The proposed technology provides a reference for the development optimization of similar reservoirs. 展开更多
关键词 the Middle East thick carbonate reservoir vertical heterogeneity concealed baffle and barrier sealing separated development units balanced waterflooding
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Types,composition and diagenetic evolution of authigenic clay minerals in argillaceous limestone of sepiolite-bearing strata:A case study of Mao-1 Member of Middle Permian Maokou Formation,eastern Sichuan Basin,SW China
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作者 SONG Jinmin WANG Jiarui +12 位作者 LIU Shugen LI Zhiwu LUO Ping JIANG Qingchun JIN Xin YANG Di HUANG Shipeng FAN Jianping YE Yuehao WANG Junke DENG Haoshuang WANG Bin GUO Jiaxin 《Petroleum Exploration and Development》 SCIE 2024年第2期351-363,共13页
The types,occurrence and composition of authigenic clay minerals in argillaceous limestone of sepiolite-bearing strata of the first member of the Middle Permian Maokou Formation(Mao-1 Member)in eastern Sichuan Basin w... The types,occurrence and composition of authigenic clay minerals in argillaceous limestone of sepiolite-bearing strata of the first member of the Middle Permian Maokou Formation(Mao-1 Member)in eastern Sichuan Basin were investigated through outcrop section measurement,core observation,thin section identification,argon ion polishing,X-ray diffraction,scanning electron microscope,energy spectrum analysis and laser ablation-inductively coupled plasma-mass spectrometry.The diagenetic evolution sequence of clay minerals was clarified,and the sedimentary-diagenetic evolution model of clay minerals was established.The results show that authigenic sepiolite minerals were precipitated in the Si4+and Mg2+-rich cool aragonite sea and sepiolite-bearing strata were formed in the Mao-1 Member.During burial diagenesis,authigenic clay minerals undergo two possible evolution sequences.First,from the early diagenetic stage A to the middle diagenetic stage A1,the sepiolite kept stable in the shallow-buried environment lack of Al3+.It began to transform into stevensite in the middle diagenetic stage A2,and then evolved into disordered talc in the middle diagenetic stage B1and finally into talc in the period from the middle diagenetic stage B2to the late diagenetic stage.Thus,the primary diagenetic evolution sequence of authigenic clay minerals,i.e.sepiolite-stevensite-disordered talc-talc,was formed in the Mao-1 Member.Second,in the early diagenetic stage A,as Al3+carried by the storm and upwelling currents was involved in the diagenetic process,trace of sepiolite started to evolve into smectite,and a part of smectite turned into chlorite.From the early diagenetic stage B to the middle diagenesis stage A1,a part of smectite evolved to illite/smectite mixed layer(I/S).The I/S evolved initially into illite from the middle diagenesis stage A2to the middle diagenesis stage B2,and then totally into illite in the late diagenesis stage.Thus,the secondary diagenetic evolution sequence of authigenic clay minerals,i.e.sepiolite-smectite-chlorite/illite,was formed in the Mao-1 Member.The types and evolution of authigenic clay minerals in argillaceous limestone of sepiolite-bearing strata are significant for petroleum geology in two aspects.First,sepiolite can adsorb and accumulate a large amount of organic matters,thereby effectively improving the quality and hydrocarbon generation potential of the source rocks of the Mao-1 Member.Second,the evolution from sepiolite to talc is accompanied by the formation of numerous organic matter pores and clay shrinkage pores/fractures,as well as the releasing of the Mg2+-rich diagenetic fluid,which allows for the dolomitization of limestone within or around the sag.As a result,the new assemblages of self-generation and self-accumulation,and lower/side source and upper/lateral reservoir,are created in the Middle Permian,enhancing the hydrocarbon accumulation efficiency. 展开更多
关键词 sepiolite-bearing strata authigenic clay minerals diagenetic evolution Mao First Member of Middle Permian Sichuan Basin
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Abaca Fiber as a Potential Reinforcer for Acoustic Absorption Material at Middle-High Frequencies
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作者 Susilo Indrawati Lila Yuwana +2 位作者 Suyatno Mochamad Zainuri Darminto 《Journal of Renewable Materials》 EI CAS 2024年第5期909-921,共13页
Recently,abacafibers have become the focus of specialized research due to their intriguing characteristics,with their outstanding mechanical properties being a particularly notable.In the conducted study,the abacafibers... Recently,abacafibers have become the focus of specialized research due to their intriguing characteristics,with their outstanding mechanical properties being a particularly notable.In the conducted study,the abacafibers underwent a preliminary treatment process involving an alkaline solution,which was composed of 0.5%sodium hydroxide(NaOH)and 50%acetic acid(CH3COOH).This process entailed immersing eachfiber in the solution for a period of one hour.This treatment led to a 52.36%reduction in lignin content compared to the levels before treatment,resulting in a dramatic decrease in the full width at half maximum(FWHM)in the XRD spectra from 1.13 to 0.13.This change indicates that thefibers became more crystalline following the treatment.The abacafibers were also characterized using BET(Brunauer Emmett Teller)measurements,which revealed that the aver-age pore length ranged from 33–49 nm and the surface area was between 13–28 m^(2)·g^(-1).The morphology of the abacafiber after alkali an hydrolisis treatment(AFAH)appeared rougher and more uniform.DMA measurements revealed a significant rise in the storage modulus of the singlefiber post-treatment,with dependencies on both frequency and temperature.AFAH exhibited an optimal absorption coefficient ofα=0.9 for frequencies above 2500 Hz.The combined effect of alkalization and hydrolyzation treatments,while resulting in an enhancement in the mechanical properties of thefibers,also reduced high-intensity noise produced by sources such as machin-ery,aircraft takeoffs and landings,etc.,across a broader working frequency range. 展开更多
关键词 Abacafiber ALKALIZATION mechanical property acoustic characteristics middle frequency
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m^(6)A modification of lncRNA in middle ear cholesteatoma
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作者 HE Jun XIE Shumin +3 位作者 JIN Li FU Jinfeng YUAN Qiulin LIU Wei 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第5期667-678,共12页
Objective:Middle ear cholesteatoma is a non-tumorous condition that typically leads to hearing loss,bone destruction,and other severe complications.Despite surgery being the primary treatment,the recurrence rate remai... Objective:Middle ear cholesteatoma is a non-tumorous condition that typically leads to hearing loss,bone destruction,and other severe complications.Despite surgery being the primary treatment,the recurrence rate remains high.Therefore,exploring the molecular mechanisms underlying cholesteatoma is crucial for discovering new therapeutic approaches.This study aims to explore the involvement of N6-methyladenosine(m^(6)A)methylation in long non-coding RNAs(lncRNAs)in the biological functions and related pathways of middle ear cholesteatoma.Methods:The m^(6)A modification patterns of lncRNA in middle ear cholesteatoma tissues(n=5)and normal post-auricular skin tissues(n=5)were analyzed using an lncRNA m^(6)A transcriptome microarray.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analyses were conducted to identify potential biological functions and signaling pathways involved in the pathogenesis of middle ear cholesteatoma.Methylated RNA immunoprecipitation(MeRIP)-PCR was used to validate the m^(6)A modifications in cholesteatoma and normal skin tissues.Results:Compared with normal skin tissues,1525 lncRNAs were differentially methylated in middle ear cholesteatoma tissues,with 1048 showing hypermethylation and 477 showing hypomethylation[fold change(FC)≥3 or<1/3,P<0.05].GO enrichment analysis indicated that hypermethylated lncRNAs were involved in protein phosphatase inhibitor activity,neuron-neuron synapse,and regulation ofα-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid(AMPA)receptor activity.Hypomethylated lncRNAs were associated with mRNA methyltransferase activity,secretory granule membrane,and mRNA methylation.KEGG analysis revealed that hypermethylated lncRNAs were mainly associated with 5 pathways:the Hedgehog signaling pathway,viral protein interaction with cytokines and cytokine receptors,mitogen-activated protein kinase(MAPK)signaling pathway,cytokine-cytokine receptor interaction,and adrenergic signaling in cardiomyocytes.Hypomethylated lncRNAs were mainly involved in 4 pathways:Renal cell carcinoma,tumor necrosis factor signaling pathway,transcriptional misregulation in cancer,and cytokine-cytokine receptor interaction.Additionally,MeRIP-PCR confirmed the changes in m^(6)A methylation levels in NR_033339,NR_122111,NR_130744,and NR_026800,consistent with microarray analysis.Real-time PCR also confirmed the significant upregulation of MAPK1 and NF-κB,key genes in the MAPK signaling pathway.Conclusion:This study reveals the m^(6)A modification patterns of lncRNAs in middle ear cholesteatoma,suggests a direction for further research into the role of lncRNA m^(6)A modification in the etiology of cholesteatoma.The findings provide potential therapeutic targets for the treatment of middle ear cholesteatoma. 展开更多
关键词 long non-coding RNA m6A modifications middle ear cholesteatoma
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Whole petroleum system in Jurassic coal measures of Taibei Sag in Tuha Basin,NW China
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作者 ZHI Dongming LI Jianzhong +6 位作者 YANG Fan CHEN Xuan WU Chao WANG Bo ZHANG Hua HU Jun JIN Jikun 《Petroleum Exploration and Development》 SCIE 2024年第3期519-534,共16页
Based on the latest results of near-source exploration in the Middle and Lower Jurassic of the Tuha Basin,a new understanding of the source rocks,reservoir conditions,and source-reservoir-cap rock combinations of the ... Based on the latest results of near-source exploration in the Middle and Lower Jurassic of the Tuha Basin,a new understanding of the source rocks,reservoir conditions,and source-reservoir-cap rock combinations of the Jurassic Shuixigou Group in the Taibei Sag is established using the concept of the whole petroleum system,and the coal-measure whole petroleum system is analyzed thoroughly.The results are obtained in three aspects.First,the coal-measure source rocks of the Badaowan Formation and Xishanyao Formation and the argillaceous source rocks of the Sangonghe Formation in the Shuixigou Group exhibit the characteristics of long-term hydrocarbon generation,multiple hydrocarbon generation peaks,and simultaneous oil and gas generation,providing sufficient oil and gas sources for the whole petroleum system in the Jurassic coal-bearing basin.Second,multi-phase shallow braided river delta–shallow lacustrine deposits contribute multiple types of reservoirs,e.g.sandstone,tight sandstone,shale and coal rock,in slope and depression areas,providing effective storage space for the petroleum reservoir formation in coal-measure strata.Third,three phases of hydrocarbon charging and structural evolution,as well as effective configuration of multiple types of reservoirs,result in the sequential accumulation of conventional-unconventional hydrocarbons.From high structural positions to depression,there are conventional structural and structural-lithological reservoirs far from the source,low-saturation structural-lithological reservoirs near the source,and tight sandstone gas,coal rock gas and shale oil accumulations within the source.Typically,the tight sandstone gas and coal rock gas are the key options for further exploration,and the shale oil and gas in the depression area is worth of more attention.The new understanding of the whole petroleum system in the coal measures could further enrich and improve the geological theory of the whole petroleum system,and provide new ideas for the overall exploration of oil and gas resources in the Tuha Basin. 展开更多
关键词 Tuha Basin Taibei Sag Middle and Lower Jurassic whole petroleum system coal measure tight oil and gas coal rock gas shale oil
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Workplace harassment faced by female Nepalese migrants working aboard
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作者 Padam P Simkhad Edwin van Teijlingen +3 位作者 Manju Gurung Samjhana Bhujel Kalpana Gyawali Sharada P Wasti 《Global Health Journal》 2024年第3期128-132,共5页
Background:Nepal has a long history of labour migration over the years.Migrants can experience a range of problems in their destination countries,and women are more at risk than men.This paper is the first to explore ... Background:Nepal has a long history of labour migration over the years.Migrants can experience a range of problems in their destination countries,and women are more at risk than men.This paper is the first to explore the problems faced by Nepalese women migrants while working abroad.Methods:This study was conducted among 1,889 women who were registered as migrant returnees at an organisation called Pourakhi Nepal.The study extracted and analysed data from a non-governmental organisation that supports returning female migrant workers in Nepal.Results:Around half(43.1%)of the women were 35 or older,30.9%were illiterate,and 63.6%were in their first overseas job.More than one-third(38.5%)had self-reported workplace harassment.Physical violence was the most prevalent(68%),followed by verbal abuse(37.5%),mental stress(29.7%),and sexual abuse(14.1%).Women who were illiterate(adjusted odds ratio[AOR]1.25,95%confidence interval[CI):1.01 to 1.55),unmarried(AOR 1.27,95%CI:1.05 to 1.56),worked abroad twice or more(AOR 1.35,95%CI:1.10 to 1.66),changed their place of work(AOR 2.38,95%CI:1.42 to 4.01),lived without documents(AOR 1.24,95%CI:1.03 to 1.50),worked as domestics(AOR 3.56,95%CI:2.03 to 6.23),worked in other than Gulf Cooperation Council countries(AOR 1.45,95%CI:1.06 to 1.99),women who did not have a fixed salary(AOR 1.64,95%CI:1.28 to 2.10)and did not receive salary(AOR 3.71,95%CI:2.88 to 4.77)were more likely to be harassed at work.Conclusion:Our findings suggest that the host governments should introduce and enforce policies protecting women in the workplace.Migrant women should be provided with better information about health risks and hazards as well as how to improve preventive measures in destination countries to reduce workplace harassment. 展开更多
关键词 Health problems Migration Exploitation Middle East South Asia
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