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Rheological properties and concentration evolution of thickened tailings under the coupling effect of compression and shear 被引量:1
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作者 Aixiang Wu Zhenqi Wang +3 位作者 Zhuen Ruan Raimund Bürger Shaoyong Wang Yi Mo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期862-876,共15页
Cemented paste backfill(CPB)is a key technology for green mining in metal mines,in which tailings thickening comprises the primary link of CPB technology.However,difficult flocculation and substandard concentrations o... Cemented paste backfill(CPB)is a key technology for green mining in metal mines,in which tailings thickening comprises the primary link of CPB technology.However,difficult flocculation and substandard concentrations of thickened tailings often occur.The rheological properties and concentration evolution in the thickened tailings remain unclear.Moreover,traditional indoor thickening experiments have yet to quantitatively characterize their rheological properties.An experiment of flocculation condition optimization based on the Box-Behnken design(BBD)was performed in the study,and the two response values were investigated:concentration and the mean weighted chord length(MWCL)of flocs.Thus,optimal flocculation conditions were obtained.In addition,the rheological properties and concentration evolution of different flocculant dosages and ultrafine tailing contents under shear,compression,and compression-shear coupling experimental conditions were tested and compared.The results show that the shear yield stress under compression and compression-shear coupling increases with the growth of compressive yield stress,while the shear yield stress increases slightly under shear.The order of shear yield stress from low to high under different thickening conditions is shear,compression,and compression-shear coupling.Under compression and compression-shear coupling,the concentration first rapidly increases with the growth of compressive yield stress and then slowly increases,while concentration increases slightly under shear.The order of concentration from low to high under different thickening conditions is shear,compression,and compression-shear coupling.Finally,the evolution mechanism of the flocs and drainage channels during the thickening of the thickened tailings under different experimental conditions was revealed. 展开更多
关键词 thickened tailings compression-shear coupling compressive yield stress shear yield stress CONCENTRATION
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Experimental study on workability and permeability of sandy soils conditioned with thickened foam
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作者 Zhiyao Feng Shuying Wang +2 位作者 Tongming Qu Xiangcou Zheng Fanlin Ling 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期532-544,共13页
Water spewing and muck plugging often occur during earth pressure balance(EPB)shield machines tunnelling in water-rich sandy strata,even though the conventional foam has been employed to condition sandy soils.In this ... Water spewing and muck plugging often occur during earth pressure balance(EPB)shield machines tunnelling in water-rich sandy strata,even though the conventional foam has been employed to condition sandy soils.In this study,a novel thickened foaming agent suitable for EPB shield tunnelling in water-rich sandy strata is developed.In contrast to conventional foam-conditioned sands,the thickened foam-conditioned sand has a low permeability due to the consistent filling of soil pores with the thickened foam,and the initial permeability coefficient decreases by approximately two orders of magnitude.It also exhibits a suitable workability,which is attributed to the enhanced capability of the thickened foam to condition sandy soils.In addition,the effect of concentration on the stability of the foam is explained by the Gibbs-Marangoni effect,and conditioning mechanisms for the thickened foam on sands are discussed from the evolution of foam bubbles. 展开更多
关键词 Earth pressure balance(EPB)shield thickened foam Foam-conditioned sand PERMEABILITY WORKABILITY
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Large eddy simulation of turbulent premixed piloted flame using artificial thickened flame model coupled with tabulated chemistry 被引量:1
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作者 Zhou YU Hongda ZHANG +1 位作者 Taohong YE Minming ZHU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第9期1277-1294,共18页
A sub-grid scale(SGS) combustion model, which combines the artificial thickened flame(ATF) model with the flamelet generated manifold(FGM) tabulation method, is proposed. Based on the analysis of laminar flame structu... A sub-grid scale(SGS) combustion model, which combines the artificial thickened flame(ATF) model with the flamelet generated manifold(FGM) tabulation method, is proposed. Based on the analysis of laminar flame structures, two self-contained flame sensors are used to track the diffusion and reaction processes with different spatial scales in the flame front, respectively. The dynamic formulation for the proposed SGS combustion model is also performed. Large eddy simulations(LESs) of Bunsen flame F3 are used to evaluate the different SGS combustion models. The results show that the proposed SGS model has the ability in predicting the distributions of temperature and velocity reasonably, while the predictions for the distributions of some species need further improvement. The snapshots of instantaneous normalized progress variables reveal that the flame is more remarkably and severely wrinkled at the flame tip for flame F3.More satisfactory results obtained by the dynamic model indicate that it can preserve the premixed flame propagation characteristics better. 展开更多
关键词 large eddy simulation(LES) artificial thickened flame model TABULATION dynamic modeling flame sensor
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Numerical modeling of cracking pattern's influence on the dynamic response of thickened tailings disposals: a periodic approach 被引量:1
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作者 Gabriel Ferrer Esteban Sáez Christian Ledezma 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第1期179-190,共12页
Copper production is an essential component of the Chilean economy. During the extraction process of copper, large quantities of waste materials(tailings) are produced, which are typically stored in large tailing po... Copper production is an essential component of the Chilean economy. During the extraction process of copper, large quantities of waste materials(tailings) are produced, which are typically stored in large tailing ponds. Thickened Tailings Disposal(TTD) is an alternative to conventional tailings ponds. In TTD, a considerable amount of water is extracted from the tailings before their deposition. Once a thickened tailings layer is deposited, it loses water and it shrinks, forming a relatively regular structure of tailings blocks with vertical cracks in between, which are then filled up with "fresh" tailings once the new upper layer is deposited. The dynamic response of a representative column of this complex structure made out of tailings blocks with softer material in between was analyzed using a periodic half-space finite element model. The tailings' behavior was modeled using an elasto-plastic multi-yielding constitutive model, and Chilean earthquake records were used for the seismic analyses. Special attention was given to the liquefaction potential evaluation of TTD. 展开更多
关键词 thickened tailings Liquefaction Periodic modeling
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THINNING OF THE THICKENED LITHOSPHERE AND ITS GEODYNAMIC CONSEQUENCE: APPLICATION FOR TIBETAN PLATEAU
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作者 Xiong Xiong,Houtse Hsu (Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China) 《地学前缘》 EI CAS CSCD 2000年第S1期368-369,共2页
As one of the most distinct tectonic blocks on the Earth’s surface, Tibetan Plateau draw great attention of the geoscientists from the world. Many authors have proposed various kinds of the mechanism to try to clarif... As one of the most distinct tectonic blocks on the Earth’s surface, Tibetan Plateau draw great attention of the geoscientists from the world. Many authors have proposed various kinds of the mechanism to try to clarify the evolution of the plateau. While many studies are often restricted to crustal units, the important role of the mantle part of the lithosphere (mantle lithosphere) during and after the collision process has not been appreciated widely. The purpose of the paper is to investigate the dynamic process of the thinning (delamination and convective removal) of the thickened lithosphere and its influence upon the uplift of the plateau.1\ Thickened lithosphere root\;Parsons and McKenzie (1978) proposed that the continental lithosphere could be thought of as consisting of two distinct parts: the mechanical and thermal boundary layers. The lower, and hotter, part is the thermal boundary layer. Its viscosity is sufficiently low that the force of gravity acting on density contrasts between the thermal boundary layer and the underlying mantle lead to the episodic sinking of the thermal boundary layer and its replacement by hot asthenosphere. When continental crust shortens and thickens, the mantle directly beneath it must also be displaced downward. In other words, mountain building process shortens horizontally and thickens vertically the mechanical boundary layer, and presumably the thermal boundary layer. And the process stretches the isotherms vertically, thus reducing the geothermal gradient. Houseman’s numerical experiments (1981) show that thickening of the thermal boundary layer enhances the density contrasts between it and the underlying asthenosphere, and so leads to its removal and replacement with hot asthenosphere. This phenomenon is called the instability of the thickened lithosphere. 展开更多
关键词 THINNING thickened LITHOSPHERE Tibetan Plateau UPLIFT
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The Mod 2 Kauffman Bracket Skein Module of Thickened Torus
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作者 Yan Xin-ming Sun Meng 《Communications in Mathematical Research》 CSCD 2018年第1期89-96,共8页
Framed links in thickened torus are studied. We define the mod 2 Kauffman bracket skein module of thickened torus and give an expression of a framed link in this module. From this expression we propose a new ambient i... Framed links in thickened torus are studied. We define the mod 2 Kauffman bracket skein module of thickened torus and give an expression of a framed link in this module. From this expression we propose a new ambient isotopic invariant of framed links. 展开更多
关键词 framed link thickened torus mod 2 Kauffman bracket skein module
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Hypoallergenicity of a thickened hydrolyzed formula in children with cow’s milk allergy
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作者 Danilo Rossetti Salvatore Cucchiara +2 位作者 AlessANDra Morace Beatrice Leter Salvatore Oliva 《World Journal of Clinical Cases》 SCIE 2019年第16期2256-2268,共13页
BACKGROUND Allergy to cow’s milk is the most frequent allergy occurring in infants and young children.The dietary management of these patients consists of the elimination of any cow’s milk proteins from the diet,and... BACKGROUND Allergy to cow’s milk is the most frequent allergy occurring in infants and young children.The dietary management of these patients consists of the elimination of any cow’s milk proteins from the diet,and for formula-fed infants,the substitution of the usual infant formula with an adapted formula that is generally based on extensively hydrolyzed cow’s milk proteins.The American Academy of Pediatrics has established specific criteria to confirm the hypoallergenicity of a formula intended for these children.AIM To assess the hypoallergenicity of a new thickened extensively hydrolyzed casein-based formula (TeHCF) in children with cow’s milk allergy (CMA).METHODS Children diagnosed with CMA through a double-blind placebo-controlled food challenge (DBPCFC) were randomly administered increased doses of a placebo formula or the TeHCF [Allernova,new thickener including fibres (Novalac)] under double-blind conditions and medical surveillance on two separate days.Otherwise,both of these formulas and a cow’s milk-based formula were randomly introduced to children who were highly suspected of having CMA on three separate days.Immediate and late reactions occurring after the introduction of any of these formulas were thoroughly recorded by the physician at the hospital and reported by parents to the physician after hospital discharge,respectively.If the children tolerated the TeHCF during the DBPCFC,they were exclusively fed this formula during a 3-mo period where potential allergic symptoms,anthropometric parameters,as secondary outcomes,and adverse events were registered.The Cow’s Milk-related Symptoms Score (CoMiSSTM) was assessed and anthropometric parameters were compared to World Health Organization (WHO) reference data.RESULTS Of the 30 children included in the study,the CMA diagnosis of 29 (mean age: 8.03 ± 7.43 mo) patients was confirmed by a DBPCFC.The children all tolerated the TeHCF during both the challenge and the subsequent 3-mo feeding period,which they all completed.During the latter period,the CoMiSSTM remained at a very low level,never exceeding its baseline value (1.4 ± 2.0),growth parameters were within WHO reference standards and no adverse event related to the TeHCF was reported.Over the first week of this period,the proportion of patients with digestive discomfort significantly decreased from 20.7%(6/29) to 3.4%(1/29),P = 0.025.The proportion of satisfaction with the overall effect of the formula reported by the parents and investigator was high,as was the formula acceptability by the child.CONCLUSION The new TeHCF meets the hypoallergenicity criteria according to the American Academy of Pediatrics standards,confirming that the tested TeHCF is adapted to the dietary management of children with CMA.Moreover,growth was adequate in the included population. 展开更多
关键词 Cow's milk ALLERGY Hypoallergenicity Tolerance thickened extensively hydrolyzed FORMULA DIGESTIVE COMFORT DIETARY management
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Piecemeal Delamination of Thickened Lithosphere Triggered Pulsed Magmatism and Mineralization during Late Mesozoic Intracontinental Orogeny in East Asia 被引量:2
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作者 ZHANG Yueqiao DONG Shuwen +1 位作者 LI Jianhua QIU Erkang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第S01期112-114,共3页
The East Asia continent is characterized by a mosaic architecture with various composing blocks,such as the North and South China blocks,which had been collaged in Late Permian to Triassic in response to the break-up ... The East Asia continent is characterized by a mosaic architecture with various composing blocks,such as the North and South China blocks,which had been collaged in Late Permian to Triassic in response to the break-up of Pangea.In the Late Mesozoic. 展开更多
关键词 East Asia Late Mesozoic magmatism intracontinental orogeny piecemeal delamination lithospheric thickening
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Effect of variations in the polar and azimuthal angles of coarse particles on the structure of drainage channels in thickened beds
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作者 Cuiping Li Gezhong Chen +4 位作者 Zhu’en Ruan Raimund Bürger Yuan Gao Hezi Hou Hui Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第12期2321-2333,共13页
The 3D reconstruction and quantitative characterization of drainage channels and coarse tailings particles in a bed were conducted in this study.The influence of variations in the azimuthal angle(θ)and polar angle(φ... The 3D reconstruction and quantitative characterization of drainage channels and coarse tailings particles in a bed were conducted in this study.The influence of variations in the azimuthal angle(θ)and polar angle(φ)of coarse particles on drainage channel structure was analyzed,and the drainage mechanism of the bed was studied.Results showed that water discharge in the bed reduced the size of pores and throat channels,increasing slurry concentration.The throat channel structure was a key component of the drainage process.Theφandθof particles changed predominantly along the length direction.The changes inφhad a cumulative plugging effect on the drainage channel and increased the difficulty of water discharge.The rake and rod formed a shear ring in the tailings bed with shear,and theθdistribution of particles changed from disorderly to orderly during the rotation process.The drainage channel was squeezed during the shearing process with the change inθ,which broke the channel structure,encouraged water discharge in the bed,and facilitated a further increase in slurry concentration.The findings of this work are expected to offer theoretical guidance for preparing high-concentration underflow in the tailings thickening process. 展开更多
关键词 tailings thickening coarse particle azimuthal angle polar angle drainage channels
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Indian plate blocked by the thickened Eurasian crust in the middle of the continental collision zone of southern Tibet
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作者 Gaochun Wang Xiaobo Tian +7 位作者 Yibing Li Tao Xu Bo Wan Yi Chen Shitan Nie Xusong Yang Sicheng Zuo Jianli Zhang 《Earthquake Research Advances》 CSCD 2023年第3期42-52,共11页
The relationship of the crustal contact between the Indian and Eurasian plates is a key issue in understanding crustal thickening and the subduction of the Indian lithosphere beneath the Qinghai-Tibetan Plateau. Acros... The relationship of the crustal contact between the Indian and Eurasian plates is a key issue in understanding crustal thickening and the subduction of the Indian lithosphere beneath the Qinghai-Tibetan Plateau. Across the middle of the Yarlung-Zangbo Suture(YZS), we deployed an ~450-km-long SN-trending wide-angle reflection/refraction profile to observe the P-wave velocity(vP) structure beneath the northern Himalaya and the southern plateau. Our results show that, 1. the high vP(~7.1 km/s) indicates that the Indian lower crust extends no more than 50 km north of the YZS. 2. The lower crust beneath the southern part of the plateau features an extremely low vP(<6.7 ± 0.2 km/s). 3. Compared with the velocities of several typical crustal lithologies in different temperature regimes, the low vPin the lower crust can be explained by felsic-intermediate granulite, which has prevented the lower crust from further eclogitization. We propose that the dip angle of the Indian lithospheric slab beneath the YZS is partly controlled by the composition of the lower crust of the plateau. In the northern middle YZS, the crust of the southern plateau is too thick and blocks the northward advancement of the Indian lower crust, resulting in the subduction of the Indian lithospheric slab into the upper mantle. The lower crust in western and eastern Lhasa is dominated by a mafic composition, and it was delaminated after eclogitization before the Miocene. The void zone generated by delamination favors the flattening and underthrusting of the Indian lower crust. 展开更多
关键词 Qinghai-Tibetan Plateau Indian lithospheric slab Wide-angle reflection/refraction Crustal P-wave velocity structure Crustal thickening
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Enhancement of thermophilic anaerobic digestion of thickened waste activated sludge by combined microwave and alkaline pretreatment 被引量:9
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作者 Yongzhi Chi Yuyou Li +2 位作者 Xuening Fei ShaopoWang Hongying Yuan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第8期1257-1265,共9页
Pretreatment of thickened waste activated sludge (TWAS) by combined microwave and alkaline pretreatment (MAP) was studied to improve thermophilic anaerobic digestion efficiency. Uniform design was applied to deter... Pretreatment of thickened waste activated sludge (TWAS) by combined microwave and alkaline pretreatment (MAP) was studied to improve thermophilic anaerobic digestion efficiency. Uniform design was applied to determine the combination of target temperature (110-210°C), microwave holding time (1-51 min), and NaOH dose (0-2.5 g NaOH/g suspended solids (SS)) in terms of their effect on volatile suspended solids (VSS) solubilization. Maximum solubilization ratio (85.1%) of VSS was observed at 210°C with 0.2 g-NaOH/g-SS and 35 min holding time. The effects of 12 different pretreatment methods were investigated in 28 thermophilic batch reactors by monitoring cumulative methane production (CMP). Improvements in methane production in the TWAS were directly related to the microwave and alkaline pretreatment of the sludge. The highest CMP was a 27% improvement over the control. In spite of the increase in soluble chemical oxygen demand concentration and the decrease in dewaterability of digested sludge, a semi-continuous thermophilic reactor fed with pretreated TWAS without neutralization (at 170~C with 1 min holding time and 0.05 g NaOH/g SS) was stable and functioned well, with volatile solid (VS) and total chemical oxygen demand (TCOD) reductions of 28% and 18%, respectively, which were higher than those of the control system. Additionally, methane yields (L@STP/g-CODaded, at standard temperature and pressure (STP) conditions of 0°C and 101.325 kPa) and (L@STP/g VSadad) increased by 17% and 13%, respectively, comoared to the control reactor. 展开更多
关键词 thickened waste activated sludge microwave pretreatment alkaline pretreatment thermophilic anaerobic digestion
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Effect of hot/warm roll-forming process on microstructural evolution and mechanical properties of local thickened U-rib for orthotropic steel deck 被引量:4
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作者 Xue-feng Peng Jing Liu +1 位作者 Jing-tao Han Dong-bin Wei 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2017年第3期335-342,共8页
To improve the strength-toughness of traditional U-rib( TUR) and solve the problem of insufficient penetration between TUR and deckplate,a new local thickened U-rib( LTUR) has been proposed to improve the fatigue ... To improve the strength-toughness of traditional U-rib( TUR) and solve the problem of insufficient penetration between TUR and deckplate,a new local thickened U-rib( LTUR) has been proposed to improve the fatigue resistance of the weld joint under the premise of not increasing thickness and strength of the TUR material. And a hot /warm roll-forming process( RFP) adopting partially induction heating to 700- 1 000℃ was carried out to fabricate LTUR. The deformation behaviors in the forming process and microstructure of LTUR have been investigated.Mechanical properties and fracture mechanism of the LTUR after hot / warm RFP have been systematically discussed. Moreover,the results are compared with those obtained in cold RFP. Mechanical properties of the LTUR deformed above the critical transformation temperature( A_(c3)) show high performance characteristics with marked fatigue resistance and superior toughness. Upon increasing the heating temperature from 700 to 900 ℃,the initial coarse ferrite-pearlite structure transform into equiaxed ultrafine ferrite( 1- 3 μm) and precipitates such as( Nb,Ti)( C,N) are uniformly distributed in the matrix. The average dislocation density of the specimens after hot rollforming at heating temperature of 900 ℃ decreases dramatically compared with those of the specimens subjected to the cold RFP. Furthermore,a typical characteristic of ductile fracture mechanism and the high impact energy are more convinced that the specimens deformed above 900 ℃ have obtained an optimal combination of strength and toughness. 展开更多
关键词 Orthotropic steel deck Local thickened U-rib Hot roll-forming PROCESS Warm roll-forming PROCESS Microstructural evolution Deformation behavior
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Strigolactones modulate cotton fiber elongation and secondary cell wall thickening 被引量:2
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作者 Yunze Wen Peng He +3 位作者 Xiaohan Bai Huizhi Zhang Yunfeng Zhang Jianing Yu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1850-1863,共14页
Cotton is one of the most important economic crops in the world,and it is a major source of fiber in the textile industry.Strigolactones(SLs)are a class of carotenoid-derived plant hormones involved in many processes ... Cotton is one of the most important economic crops in the world,and it is a major source of fiber in the textile industry.Strigolactones(SLs)are a class of carotenoid-derived plant hormones involved in many processes of plant growth and development,although the functions of SL in fiber development remain largely unknown.Here,we found that the endogenous SLs were significantly higher in fibers at 20 days post-anthesis(DPA).Exogenous SLs significantly increased fiber length and cell wall thickness.Furthermore,we cloned three key SL biosynthetic genes,namely GhD27,GhMAX3,and GhMAX4,which were highly expressed in fibers,and subcellular localization analyses revealed that GhD27,GhMAX3,and GhMAX4 were localized in the chloroplast.The exogenous expression of GhD27,GhMAX3,and GhMAX4 complemented the physiological phenotypes of d27,max3,and max4 mutations in Arabidopsis,respectively.Knockdown of GhD27,GhMAX3,and GhMAX4 in cotton resulted in increased numbers of axillary buds and leaves,reduced fiber length,and significantly reduced fiber thickness.These findings revealed that SLs participate in plant growth,fiber elongation,and secondary cell wall formation in cotton.These results provide new and effective genetic resources for improving cotton fiber yield and plant architecture. 展开更多
关键词 STRIGOLACTONES fiber elongation secondary cell wall thickening COTTON
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Predictive value of diaphragm ultrasound for mechanical ventilation outcome in patients with acute exacerbation of chronic obstructive pulmonary disease 被引量:1
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作者 Lei-Lei Qu Wen-Ping Zhao +1 位作者 Ji-Ping Li Wei Zhang 《World Journal of Clinical Cases》 SCIE 2024年第26期5893-5900,共8页
BACKGROUND Acute exacerbation of chronic obstructive pulmonary disease(AECOPD)is often combined with respiratory failure,which increases the patient's morbidity and mortality.Diaphragm ultrasound(DUS)has developed... BACKGROUND Acute exacerbation of chronic obstructive pulmonary disease(AECOPD)is often combined with respiratory failure,which increases the patient's morbidity and mortality.Diaphragm ultrasound(DUS)has developed rapidly in the field of critical care in recent years.Studies with DUS monitoring diaphragm-related rapid shallow breathing index have demonstrated important results in guiding intensive care unit patients out of the ventilator.Early prediction of the indications for withdrawal of non-invasive ventilator and early evaluation of patients to avoid or reduce disease progression are very important.AIM To explore the predictive value of DUS indexes for non-invasive ventilation outcome in patients with AECOPD.METHODS Ninety-four patients with AECOPD who received mechanical ventilation in our hospital from January 2022 to December 2023 were retrospectively analyzed,and they were divided into a successful ventilation group(68 cases)and a failed ventilation group(26 cases)according to the outcome of ventilation.The clinical data of patients with successful and failed noninvasive ventilation were compared,and the independent predictors of noninvasive ventilation outcomes in AECOPD patients were identified by multivariate logistic regression analysis.RESULTS There were no significant differences in gender,age,body mass index,complications,systolic pressure,heart rate,mean arterial pressure,respiratory rate,oxygen saturation,partial pressure of oxygen,oxygenation index,or time of inspiration between patients with successful and failed mechanical ventilation(P>0.05).The patients with successful noninvasive ventilation had shorter hospital stays and lower partial pressure of carbon dioxide(PaCO_(2))than those with failed treatment,while potential of hydrogen(pH),diaphragm thickening fraction(DTF),diaphragm activity,and diaphragm movement time were significantly higher than those with failed treatment(P<0.05).pH[odds ratio(OR)=0.005,P<0.05],PaCO_(2)(OR=0.430,P<0.05),and DTF(OR=0.570,P<0.05)were identified to be independent factors influencing the outcome of mechanical ventilation in AECOPD patients.CONCLUSION The DUS index DTF can better predict the outcome of non-invasive ventilation in AECOPD patients. 展开更多
关键词 Diaphragm ultrasound Mechanical ventilation Acute exacerbation of chronic obstructive pulmonary disease Predictive value Diaphragm thickening fraction Diaphragm activity
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Thickening progression mechanism of silica fume-oil well cement composite system at high temperatures
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作者 Hang Zhang Miao-Miao Hu +7 位作者 Peng-Peng Li Guo-Qing Liu Qing-Lu Chang Jie Cao Ming Liu Wen-Hua Xu Xiu-Jian Xia Jin-Tang Guo 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2793-2805,共13页
This work studied the thickening progression mechanism of the silica fume-oil well cement composite system at high temperatures(110-180.C)in order to provide a theoretical guidance for the rational application of sili... This work studied the thickening progression mechanism of the silica fume-oil well cement composite system at high temperatures(110-180.C)in order to provide a theoretical guidance for the rational application of silica fume in the cementing engineering.Results showed that silica fume seldom affected the thickening progression of oil well cement slurry at 110-120.C,but when temperature reached above130.C,it would aggravate the bulging degree of thickening curves and significantly extend the thickening time,meanwhile causing the abnormal“temperature-based thickening time reversal”and“dosage-based thickening time reversal”phenomena in the range of 130-160.C and 170-180.C respectively.At 130-160.C,the thickening time of oil well cement slurry was mainly associated with the generation rate of calcium hydroxide(CH)crystal.The introduced silica fume would be attracted to the cement minerals'surface that were hydrating to produce CH and agglomerate together to form an“adsorptive barrier”to hinder further hydration of the inner cement minerals.This“adsorptive barrier”effect strengthened with the rising temperature which extended the thickening time and caused the occurrence of the“temperature-based thickening time reversal”phenomenon.At 170-180.C,the pozzolanic activity of silica fume significantly enhanced and considerable amount of C-S-H was generated,thus the“temperature-based thickening time reversal”vanished and the“dosage-based thickening time reversal”was presented. 展开更多
关键词 Silica fume Oil well cement Thickening time reversal Pozzolanic reaction Adsorptive barrier CH and C-S-H
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Experimental study of solid-liquid origami composite structures with improved impact resistance
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作者 Shuheng Wang Zhanyu Wang +5 位作者 Bei Wang Zhi Liu Yunzhu Ni Wuxing Lai Shan Jiang Yong An Huang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第2期118-123,共6页
In this paper,a liquid-solid origami composite design is proposed for the improvement of impact resistance.Employing this design strategy,Kresling origami composite structures with different fillings were designed and... In this paper,a liquid-solid origami composite design is proposed for the improvement of impact resistance.Employing this design strategy,Kresling origami composite structures with different fillings were designed and fabricated,namely air,water,and shear thickening fluid(STF).Quasi-static compression and drop-weight impact experiments were carried out to compare and reveal the static and dynamic mechanical behavior of these structures.The results from drop-weight impact experiments demonstrated that the solid-liquid Kresling origami composite structures exhibited superior yield strength and reduced peak force when compared to their empty counterparts.Notably,the Kresling origami structures filled with STF exhibited significantly heightened yield strength and reduced peak force.For example,at an impact velocity of 3 m/s,the yield strength of single-layer STF-filled Kresling origami structures increased by 772.7%and the peak force decreased by 68.6%.This liquid-solid origami composite design holds the potential to advance the application of origami structures in critical areas such as aerospace,intelligent protection and other important fields.The demonstrated improvements in impact resistance underscore the practical viability of this approach in enhancing structural performance for a range of applications. 展开更多
关键词 Solid-liquid design Origami structure Impact resistance Shear thickening fluid
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Analysis of thermal management and anti-mechanical abuse of multi-functional battery modules based on magneto-sensitive shear thickening fluid
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作者 Yang XIONG Bo LU +1 位作者 Yicheng SONG Junqian ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期529-542,共14页
Electric vehicles(EVs)have garnered significant attention as a vital driver of economic growth and environmental sustainability.Nevertheless,ensuring the safety of high-energy batteries is now a top priority that cann... Electric vehicles(EVs)have garnered significant attention as a vital driver of economic growth and environmental sustainability.Nevertheless,ensuring the safety of high-energy batteries is now a top priority that cannot be overlooked during large-scale applications.This paper proposes an innovative active protection and cooling integrated battery module using smart materials,magneto-sensitive shear thickening fluid(MSTF),which is specifically designed to address safety threats posed by lithium-ion batteries(LIBs)exposed to harsh mechanical and environmental conditions.The theoretical framework introduces a novel approach for harnessing the smoothed-particle hydrodynamics(SPH)methodology that incorporates the intricate interplay of non-Newtonian fluid behavior,capturing the fluid-structure coupling inherent to the MSTF.This approach is further advanced by adopting an enhanced Herschel-Bulkley(H-B)model to encapsulate the intricate rheology of the MSTF under the influence of the magnetorheological effect(MRE)and shear thickening(ST)behavior.Numerical simulation results show that in the case of cooling,the MSTF is an effective cooling medium for rapidly reducing the temperature.In terms of mechanical abuse,the MSTF solidifies through actively applying the magnetic field during mechanical compression and impact within the battery module,resulting in 66%and 61.7%reductions in the maximum stress within the battery jellyroll,and 31.1%and 23%reductions in the reaction force,respectively.This mechanism effectively lowers the risk of short-circuit failure.The groundbreaking concepts unveiled in this paper for active protection battery modules are anticipated to be a valuable technological breakthrough in the areas of EV safety and lightweight/integrated design. 展开更多
关键词 magneto-sensitive shear thickening fluid(MSTF) battery module impact protection temperature control integrated design
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Interest of thoracic ultrasound after cardiac surgery or interventional cardiology
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作者 Martin Boussuges Philippe Blanc +1 位作者 Fabienne Bregeon Alain Boussuges 《World Journal of Cardiology》 2024年第3期118-125,共8页
Thoracic ultrasound has attracted much interest in detecting pleural effusion or pulmonary consolidation after cardiac surgery.In 2016,Trovato reported,in the World Journal of Cardiology,the interest of using,in addit... Thoracic ultrasound has attracted much interest in detecting pleural effusion or pulmonary consolidation after cardiac surgery.In 2016,Trovato reported,in the World Journal of Cardiology,the interest of using,in addition to echocardiography,thoracic ultrasound.In this editorial,we highlight the value of assessing diaphragm function after cardiac surgery and interventional cardiology pro-cedures.Various factors are able to impair diaphragm function after such interventions.Diaphragm motion may be decreased by chest pain secondary to sternotomy,pleural effusion or impaired muscle function.Hemidiaphragmatic paralysis may be secondary to phrenic nerve damage complicating cardiac surgery or atrial fibrillation ablation.Diagnosis may be delayed.Indeed,respi-ratory troubles induced by diaphragm dysfunction are frequently attributed to pre-existing heart disease or pulmonary complications secondary to surgery.In addition,elevated hemidiaphragm secondary to diaphragm dysfunction is sometimes not observed on chest X-ray performed in supine position in the intensive care unit.Analysis of diaphragm function by ultrasound during the recovery period appears essential.Both hemidiaphragms can be studied by two complementary ultrasound methods.The mobility of each hemidiaphragms is measured by M-mode ultrasonography.In addition,recording the percentage of inspiratory thickening provides important information about the quality of muscle function.These two approaches make it possible to detect hemidiaphragm paralysis or dysfunction.Such a diagnosis is important because persistent diaphragm dysfunction after cardiac surgery has been shown to be associated with adverse respiratory outcome.Early respiratory physio-therapy is able to improve respiratory function through strengthening of the inspiratory muscles i.e.diaphragm and accessory inspiratory muscles. 展开更多
关键词 ULTRASONOGRAPHY DIAPHRAGM Phrenic nerve Hemidiaphragm Thickening fraction PHYSIOTHERAPY
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Shear Thickening Fluids Based on Additives with Different Concentrations and Molecular Chain Lengths 被引量:10
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作者 徐钰蕾 龚兴龙 +3 位作者 彭超 孙英强 江万权 张忠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第3期342-346,I0002,共6页
Shear thickening fluids (STFs) based on additives with different concentrations and molecular chain lengths were investigated. STF samples were prepared with silica and additive dispersed in polyethylene glycol (PE... Shear thickening fluids (STFs) based on additives with different concentrations and molecular chain lengths were investigated. STF samples were prepared with silica and additive dispersed in polyethylene glycol (PEG) 400, where three types of additives with different molecular chain lengths of PEG4000, PEG6000, and PEG10000 were used. For PEG10000, different concentrations, including 0, 1%, 3%, and 5%, were selected to study the influences of additive concentrations. Rheological properties of the samples were measured with a rheometer. The results show that the shear thickening effect was significantly enhanced with the increase of the concentration and the molecular chain length of additives. The mechanism of enhancement was quantitatively explained with the formation of large particles clusters. 展开更多
关键词 Shear thickening fluid ADDITIVE Polyethylene glycol CONCENTRATION Molecular chain length
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Geochemistry and Genesis of the Late Jurassic Granitoids at Northern Great Hinggan Range:Implications for Exploration 被引量:10
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作者 WU Guang CHEN Yanjing +3 位作者 SUN Fengyue ZHANG Zhe LIU Ankun LI Zhitong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第2期321-332,共12页
The Longgouhe and Ershiyizhan intrusions of the Late Jurassic, located in the Upper Heilongjiang Basin of the northern Great Hinggan Range, are closely related to porphyry Cu-Au mineralizations. In lithology the intru... The Longgouhe and Ershiyizhan intrusions of the Late Jurassic, located in the Upper Heilongjiang Basin of the northern Great Hinggan Range, are closely related to porphyry Cu-Au mineralizations. In lithology the intrusions are quartz diorite, quartz monzodiorite and granodiorite of high-K caIc-alkaline series, with minor aspects of shoshonite series. Their SiO2 and A1203 contents range from 61.37% to 66.59% and 15.35% to 17.06%, respectively. The MgO content ranges from 2.02 % to 3.47 %, with Mg# indices of 44-59. The (La/Yb)N and Eu/Eu* values range from 16.85 to 81.73 and 0.68 to 0.93, respectively, showing strong differentiation rare earth element (REE) patterns similar to those of adakites. The rocks are enriched in Ba, Sr and light REE (LREE), obviously depleted in Nb and Ta, slightly depleted in Rb and Ti, and poor in Yb and Y, with Yb and Y contents of 0.31-1.32 ppm and 4.32-12.07 ppm, respectively. As indicated by Sr/Y ratios of 67.74-220.60, the rocks are characterized by low-Y and high-Sr contents, which characterize the adakites in the world. Holistically, geochemical tracers suggest that the interested intrusions are adakitic rocks. Given that the Paleo- Asian Ocean and Mongol-Okhotsk Ocean were closed in the Late Paleozoic and Permian-Middle Jurassic, respectively, the interested intrusions should be formed by partial melting of delaminated crust, which had been thickened during collisional orogeny between the Siberian and Mongolian- Sinokorean continents. 展开更多
关键词 ADAKITE GEOCHEMISTRY Late Jurassic continental collision thickened crust Great Hinggan Range
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