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Migration/transformation characteristics of heavy metals and polycyclic aromatic hydrocarbons in the co-liquefaction treatment of pig manure and lignocellulosic biomass
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作者 Zimin Luo Xinyi Huang +3 位作者 Chunfei Zhou Min Jiang Xiaoping Liu Huajun Huang 《Chinese Journal of Chemical Engineering》 2025年第6期222-234,共13页
The migration/transformation characteristics of heavy metals and polycyclic aromatic hydrocarbons(PAHs) during the co-liquefaction of pig manure and rice straw/wood sawdust were explored in this study.More than 87% of... The migration/transformation characteristics of heavy metals and polycyclic aromatic hydrocarbons(PAHs) during the co-liquefaction of pig manure and rice straw/wood sawdust were explored in this study.More than 87% of the heavy metals in feedstocks were enriched in hydrochars.The decreased proportion of active heavy metals in the hydrochars suggested partial passivation of the heavy metals.The pollution degree and risk of heavy metals were significantly mitigated from high and considerable levels in pig manure to moderate and low levels in hydrochar,respectively.Compared with commercial diesel,bio-oil products still contained an undesirable amount of heavy metals.PAHs were re-synthesized during liquefaction,with a net synthesis amount of 29.65-73.98 mg·kg^(-1).Moreover,the PAHs mainly existed in bio-oils,with a content of 57.32-132.33 mg·kg^(-1) and a toxicity equivalent of3.25-8.19 mg·kg^(-1).Compared to pig manure,the hydrochars presented a lower content of PAHs(1.76-3.53 mg·kg^(-1) versus 3.73 mg·kg^(-1)) and a smaller toxicity equivalent(0.14-0.22 mg·kg^(-1) versus0.26 mg·kg^(-1)).Interestingly,introducing lignocellulose(especially for rice straw) during the liquefaction of pig manure further mitigated the pollution degree/risk of heavy metals and PAHs.Overall,hydrochar reached a safe utilization level,while bio-oil products needed further clarification. 展开更多
关键词 Waste treatment LIQUEFACTION Pollution Heavy metals PAHS migration/transformation
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Cell type-dependent role of transforming growth factor-βsignaling on postnatal neural stem cell proliferation and migration
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作者 Kierra Ware Joshua Peter +1 位作者 Lucas McClain Yu Luo 《Neural Regeneration Research》 2026年第3期1151-1161,共11页
Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postn... Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postnatal neurogenesis remains unclear.In this study,to define the precise role of transforming growth factor-βsignaling in postnatal neurogenesis at distinct stages of the neurogenic cascade both in vitro and in vivo,we developed two novel inducible and cell type-specific mouse models to specifically silence transforming growth factor-βsignaling in neural stem cells in(mGFAPcre-ALK5fl/fl-Ai9)or immature neuroblasts in(DCXcreERT2-ALK5fl/fl-Ai9).Our data showed that exogenous transforming growth factor-βtreatment led to inhibition of the proliferation of primary neural stem cells while stimulating their migration.These effects were abolished in activin-like kinase 5(ALK5)knockout primary neural stem cells.Consistent with this,inhibition of transforming growth factor-βsignaling with SB-431542 in wild-type neural stem cells stimulated proliferation while inhibited the migration of neural stem cells.Interestingly,deletion of transforming growth factor-βreceptor in neural stem cells in vivo inhibited the migration of postnatal born neurons in mGFAPcre-ALK5fl/fl-Ai9 mice,while abolishment of transforming growth factor-βsignaling in immature neuroblasts in DCXcreERT2-ALK5fl/fl-Ai9 mice did not affect the migration of these cells in the hippocampus.In summary,our data supports a dual role of transforming growth factor-βsignaling in the proliferation and migration of neural stem cells in vitro.Moreover,our data provides novel insights on cell type-specific-dependent requirements of transforming growth factor-βsignaling on neural stem cell proliferation and migration in vivo. 展开更多
关键词 adult neurogenesis DOUBLECORTIN HIPPOCAMPUS migration neural stem cells PROLIFERATION transforming growth factor-β
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Migration and morphological transformation of Mn^(2+)and its effect on microbial community in the A^(2)O process
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作者 Xiaohui Xu Jiexiong Zhong +4 位作者 Xinyao Hao Qun Liu Min Lu Xiaohui Guan Lanhe Zhang 《Journal of Environmental Sciences》 2025年第11期404-416,共13页
Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the ... Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the pollutant removal,metal distribution patterns and composition of microbial communities were investigated in a an anaerobic/anoxic/oxic(A^(2)O)process.The results showed that when Mn^(2+)concentration was 5 mg/L,the efficiencies for the removal of chemical oxygen demand(COD),total nitrogen(TN)and total phosphorus(TP)attained remarkable levels of 96%,93%,and 99%,respectively.In the sludge,the distribution pattern of Mn^(2+)concentration was tightly bound extracellular polymeric substances(TB-EPS)>supernatant>loosely bound EPS(LB-EPS)>soluble microbial products(SMP).Mn^(2+)was found to enrich and accumulate in the microorganism cells.In addition,Mn^(2+)was mainly found in residual fractions and reducible fractions of pellet that manganese was present.The pellet was discovered to contain a substantial quantity of manganese,which was present in various oxidation states,including Mn^(4+),Mn^(3+)and Mn^(2+).The escalating levels of Mn^(2+)led to a reduction in the richness and diversity of microbial communities inhabiting various regions of the A^(2)O reactor.Nonetheless,the uniformity experienced only subtle alterations.Proteobacteria and Bacteroidetes emerged as the leading phyla within the microbial ecosystem,experiencing a steady rise in their respective proportions.The dominant bacterial groups,Azospira and Dechromonas,experienced an incremental increase in their relative prevalence,which played a constructive role in the process of pollutant removal. 展开更多
关键词 Manganese ion Anaerobic/anoxic/oxic(A^(2)O)reactor migration and transformation Morphology Microbial community
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Migration and Transformation of Coated Controlled Release Nitrogen in Soil under Co-situs Application Mode 被引量:12
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作者 肖强 王甲辰 +4 位作者 左强 张琳 刘宝存 赵同科 邹国元 《Agricultural Science & Technology》 CAS 2009年第6期144-149,共6页
By using field trials, the migration and transformation of coated controlled release nitrogen (YZS80) in soil under the co-situs application mode were studied. The results indicated that YZS80 nitrogen dissolved out... By using field trials, the migration and transformation of coated controlled release nitrogen (YZS80) in soil under the co-situs application mode were studied. The results indicated that YZS80 nitrogen dissolved out in average speed of about 0.4%/d and 32% totally in 80 d compared with common compound fertUizer. For YZS80, in the vertical downward direction of application points, urea nitrogen content increased significantly (P 〈0.05) in the 45 -80 d and the 30 -60 cm soil layers; nitrate nitrogen content was little change range and in moderate (10 -100 mg/kg) in 0 -80 d and 10 -60 cm soil layers, but increased significantly ( P 〈0.05) 45 -80 d compared to 0 -45 d; ammonium nitrogen content was significant lower (P〈0.05) before 45 d in 10 -30 cm soil layers, but significant higher(P〈0.05) after 45 d in 10 -60 cm soil layers; NO3^- -N/NH4^+ -N meets gradually the needs of the crop with the extension of time. Under the co-situs application mode, the possibility of burning root and salt injury and loss dsk of nitrate leaching is a significant reduction. 展开更多
关键词 Co-situs application Slow/controlled release fertilizer migration transformation
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Small extracellular vesicles derived from hair follicle neural crest stem cells enhance perineurial cell proliferation and migration via the TGF-β/SMAD/HAS2 pathway
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作者 Yiming Huo Bing Xiao +8 位作者 Haojie Yu Yang Xu Jiachen Zheng Chao Huang Ling Wang Haiyan Lin Jiajun Xu Pengfei Yang Fang Liu 《Neural Regeneration Research》 2026年第5期2060-2072,共13页
Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration vi... Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration via paracrine signaling;however,their clinical applications are limited by potential risks such as tumorigenesis and xenogeneic immune rejection,which are similar to the risks associated with other stem cell transplantations.The present study therefore focuses on small extracellular vesicles derived from hair follicle neural crest stem cells,which preserve the bioactive properties of the parent cells while avoiding the transplantation-associated risks.In vitro,small extracellular vesicles derived from hair follicle neural crest stem cells significantly enhanced the proliferation,migration,tube formation,and barrier function of perineurial cells,and subsequently upregulated the expression of tight junction proteins.Furthermore,in a rat model of sciatic nerve defects bridged with silicon tubes,treatment with small extracellular vesicles derived from hair follicle neural crest stem cells resulted in higher tight junction protein expression in perineurial cells,thus facilitating neural tissue regeneration.At 10 weeks post-surgery,rats treated with small extracellular vesicles derived from hair follicle neural crest stem cells exhibited improved nerve function recovery and reduced muscle atrophy.Transcriptomic and micro RNA analyses revealed that small extracellular vesicles derived from hair follicle neural crest stem cells deliver mi R-21-5p,which inhibits mothers against decapentaplegic homolog 7 expression,thereby activating the transforming growth factor-β/mothers against decapentaplegic homolog signaling pathway and upregulating hyaluronan synthase 2 expression,and further enhancing tight junction protein expression.Together,our findings indicate that small extracellular vesicles derived from hair follicle neural crest stem cells promote the proliferation,migration,and tight junction protein formation of perineurial cells.These results provide new insights into peripheral nerve regeneration from the perspective of perineurial cells,and present a novel approach for the clinical treatment of peripheral nerve defects. 展开更多
关键词 hair follicle neural crest stem cells HAS2 migration miR-21-5p perineurial cells proliferation peripheral nerve injury SMAD7 small extracellular vesicles transforming growth factor-β/SMAD signaling pathway
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Retraction:MicroRNA-133b Inhibits Proliferation,Cellular Migration,and Invasion via Targeting LASP1 in Hepatocarcinoma Cells
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作者 Oncology Research Editorial Office 《Oncology Research》 2026年第1期621-621,共1页
The published article titled“MicroRNA-133b Inhibits Proliferation,Cellular Migration,and Invasion via Targeting LASP1 in Hepatocarcinoma Cells”has been retracted from Oncology Research,Vol.25,No.8,2017,pp.1269–1282.
关键词 lasp cellular migration PROLIFERATION INVASION hepatocarcinoma cells targeting lasp microrna b
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Redundant source-wavelet amplitude influence in wave-equation migration/demigration flow and its removal
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作者 QianCheng Liu JiaLe Kang Jie Li 《Earth and Planetary Physics》 2026年第1期75-81,共7页
In wave-equation migration and demigration,the cross-correlation imaging/forwarding step implicitly injects an additional copy of the source wavelet,so that the amplitude spectrum of the wavelet is applied redundantly... In wave-equation migration and demigration,the cross-correlation imaging/forwarding step implicitly injects an additional copy of the source wavelet,so that the amplitude spectrum of the wavelet is applied redundantly(effectively imposing a wavelet-spectrum weighting,often akin to an amplitude-squared bias).This redundancy degrades structural fidelity and amplitude balance yet is frequently overlooked.We(i)formalize the mechanism by which cross-correlation duplicates the source-wavelet amplitude effect in both migration and demigration,and(ii)introduce a source-equalized operator that removes the redundancy by deconvolving(or dividing by)the wavelet amplitude spectrum in the imaging condition and its demigration counterpart,while leaving phase/kinematics intact.Using a band-limited Ricker wavelet on a two-layer model and on Marmousi,we show that,if unmanaged,the redundant wavelet spectrum broadens main lobes,introduces ringing,and suppresses vertical resolution in migrated images,and inflates spectrum mismatches between demigrated and observed data even when peak times agree.With our correction,images recover observed-data-consistent bandwidth and sharpened interfaces,and demigrated data also exhibit improved spectrum conformity and reduced amplitude misfit.The results clarify when source amplitudes matter,why cross-correlation makes them redundantly matter,and how a lightweight spectral correction restores physically meaningful amplitude behavior in wave-equation migration/demigration. 展开更多
关键词 wave-equation migration DEmigration cross-correlation imaging condition source wavelet amplitude spectrum spectral deconvolution
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Effect of fluoride roasting on copper species transformation on chrysocolla surfaces and its role in enhanced sulfidation flotation
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作者 Yingqiang Ma Xin Huang +5 位作者 Yafeng Fu Zhenguo Song Sen Luo Shuanglin Zheng Feng Rao Wanzhong Yin 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期165-176,共12页
It is difficult to recover chrysocolla from sulfidation flotation which is closely related to the mineral surface composition.In this study,the effects of fluoride roasting on the surface composition of chrysocolla we... It is difficult to recover chrysocolla from sulfidation flotation which is closely related to the mineral surface composition.In this study,the effects of fluoride roasting on the surface composition of chrysocolla were investigated,its impact on sulfidation flotation was explored,and the mechanisms involved in both fluoride roasting and sulfidation flotation were discussed.With CaF_(2)as the roasting reagent,Na_(2)S·9H_(2)O as the sulfidation reagent,and sodium butyl xanthate(NaBX)as the collector,the results of the flotation experiments showed that fluoride roasting improved the floatability of chrysocolla,and the recovery rate increased from 16.87%to 82.74%.X-ray diffraction analysis revealed that after fluoride roasting,approximately all the Cu on the chrysocolla surface was exposed in the form of CuO,which could provide a basis for subsequent sulfidation flotation.The microscopy and elemental analyses revealed that large quantities of"pagoda-like"grains were observed on the sulfidation surface of the fluoride-roasted chrysocolla,indicating high crystallinity particles of copper sulfide.This suggests that the effect of sulfide formation on the chrysocolla surface was more pronounced.X-ray photoelectron spectroscopy revealed that fluoride roasting increased the relative contents of sulfur and copper on the surface and that both the Cu~+and polysulfide fractions on the surface of the minerals increased.This enhances the effect of sulfidation,which is conducive to flotation recovery.Therefore,fluoride roasting improved the effect of copper species transformation and sulfidation on the surface of chysocolla,promoted the adsorption of collectors,and improved the recovery of chrysocolla from sulfidation flotation. 展开更多
关键词 sulfidation flotation CHRYSOCOLLA fluoride roasting copper species transformation enhanced sulfidation
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Tracking a High-Tech Transition--How technology is powering Guangdong’s manufacturing transformation
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作者 HU FAN 《ChinAfrica》 2026年第1期30-32,共3页
The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them w... The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them was not a typical exhibition hall,but a building shaped like a gleaming stainless-steel cooking pot. 展开更多
关键词 othello kitchenware museum TECHNOLOGY industrial strength high tech transition guangdong manufacturing transformation
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A simulation analysis of the migration and transformation of pollutants contained in landfill leachate 被引量:4
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作者 WANGHong-qi TIANKai-ming +2 位作者 QIYong-qiang CHENJia-jun WANGYa-nan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第6期827-835,共9页
A dynamic composite model for a soil-water system that can be used to simulate the movement of leachate from a landfill. The composite model includes nine sub-models that trace water movement and the migration and tra... A dynamic composite model for a soil-water system that can be used to simulate the movement of leachate from a landfill. The composite model includes nine sub-models that trace water movement and the migration and transformation of five pollutants(organic N, NH - 4, NO - 3, NO - 2, and Cl -) in saturated and unsaturated soil. The model to simulate the movement of leachate from a landfill in Laogang Town, Shanghai City was used. In this application, the values for the model parameters were obtained by performing a laboratory simulation experiment of water movement and pollutant migration and transformation in soil columns. Soil and leachate obtained from the landfill site and its vicinity were used in the laboratory experiments. The model was then used to simulate leachate movement and pollutant activity during the ten-year period when the landfill was in operation and in the twenty-year period following its closure. The simulation results revealed that the leachate migrated into the groundwater at the rate of 90—100 meters per year. This model can be applied in the design of future landfills in China for the purpose of assessing and forecasting leachate plumes. 展开更多
关键词 simulation LEACHATE LANDFILL pollutant migration pollutant transformation mathematical model
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TGF-β1-promoted epithelial-to-mesenchymal transformation and cell adhesion contribute to TGF-β1-enhanced cell migration in SMMC-7721 cells 被引量:30
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作者 ZHENXU MINXIONGSHEN +2 位作者 DONGZHUMA LIYINGWANG XILIANGZHA 《Cell Research》 SCIE CAS CSCD 2003年第5期343-350,共8页
Transforming growth factor-b 1 (TGF-β1), a multi-function polypeptide, is a double-edged sword in cancer. For some tumor cells, TGF-β1 is a potent growth inhibitor and apoptosis inducer. More commonly, TGF-β1 loses... Transforming growth factor-b 1 (TGF-β1), a multi-function polypeptide, is a double-edged sword in cancer. For some tumor cells, TGF-β1 is a potent growth inhibitor and apoptosis inducer. More commonly, TGF-β1 loses its growth-inhibitory and apoptosis-inducing effects, but stimulates the metastatic capacity of tumor cells. It is currently little known about TGF-β1-promoted cell migration in hepatocellular carcinoma (HCC) cells, let alone its mechanism. In this study, we found that TGF-β1 lost its tumor-suppressive effects, but significantly stimulated cell migration in SMMC-7721 human HCC cells. By FACS and Western blot analysis, we observed that TGF-β1 enhanced the expression of α5β1 integrin obviously, and subsequently stimulated cell adhesion onto fibronectin (Fn). Furthermore, we observed that TGF-β1 could also promote SMMC-7721 cells adhesion onto laminin (Ln). Our data also provided evidences that TGF-β1 induced epithelial-to-mesenchymal transformation (EMT) in SMMC-7721 cells. First, SMMC-7721 cells clearly switched to the spindle shape morphology after TGF-β1 treatment. Furthermore, TGF-β1 induced the down-regulation of E-cadherin and the nuclear translocation of β-catenin. These results indicated that TGF-β1-promoted cell adhesion and TGF-β1-induced epithelial-to-mesenchymal transformation might be both responsible for TGF-β1-enhanced cell migration. 展开更多
关键词 TGF-Β1 cell migration epitheIial-to-mesenchymal transformation α5β1 integrin.
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Transformation and migration of phosphorus in excess sludge reduction pretreatment by alkaline ferrate oxidation combined with anaerobic digestion 被引量:4
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作者 Xiang Li Yan Yuan +4 位作者 Yong Huang Chao-ran Guo Run Jin Ting-ting Liu Jun Ma 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第6期224-234,共11页
Recently,more and more attention has been paid to the strong oxidation ability of newly prepared potassium ferrate(NAPF) in sludge reduction process,but less attention has been paid to the change of phosphorus in this... Recently,more and more attention has been paid to the strong oxidation ability of newly prepared potassium ferrate(NAPF) in sludge reduction process,but less attention has been paid to the change of phosphorus in this process.The feasibility of phosphorus migration and transformation during excess sludge reduction pretre atment using NAPF pre-oxidation combined with anaerobic digestion was investigated.After 70 mg/g suspended solids NAPF pretreatment and 16 days anaerobic digestion,the solid-phase volatile suspended solids decreased by 44.2%,and much organic matter had been released into the liquid-phase and then degraded during digestion by indigenous microorganisms.As the sludge pre-oxidation process was performed,solid-phase organic phosphorus and chemically combined phosphorus also released into the liquid-phase as PO4^3-,peaking at 100 mg/L.During anaerobic digestion,the Fe3+in the liquid-phase was gradually reduced to Fe2+,and then formed Fe^2+-PO4^3- compound crystals and re-migrated to the solid-phase.The concentration of PO4^3- decreased to 17.08± 1.1 mg/L in the liquid-phase after anaerobic digestion.Finally,the phosphorus in the Fe^2+-PO4^3- compound accounts for 80% of the total phosphorus in the solid-phase.A large number of vivianite crystals in sludge were observed.Therefore,this technology not only effectively reduces sludge,but also increases the proportion of PO43-in the sludge in the form of Vivianite. 展开更多
关键词 Excess sludge Alkaline ferrate(NAPF) PRE-OXIDATION Anaerobic digestion PHOSPHORUS migration and transformation
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Structure and Migration Characteristic of Heterointerfaces During the Phase Transformation from L1_2 to DO_(22) Phase 被引量:1
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作者 张明义 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第5期814-819,共6页
Based on the microscopic phase-field model, the structure and migration characteristic of ordered domain interfaces formed between DO22 and L12 phase are investigated, and the atomistic mechanism of phase transformati... Based on the microscopic phase-field model, the structure and migration characteristic of ordered domain interfaces formed between DO22 and L12 phase are investigated, and the atomistic mechanism of phase transformation from L12 (Ni3Al) to DO22 (Ni3V) in Ni75AlxV25-x alloys are explored, using the simulated microstructure evolution pictures and the occupation probability evolution of alloy elements at the interface. The results show that five kinds of heterointerfaces are formed between DO22 and L12 phase and four of them can migrate during the phase transformation from L12 to DO22 except the interface (002)D//(001)L. The structure of interface (100)D//(200)L and interface (100)D//(200)L·^1/2[001] remain the same before and after migration, while the interface (002)D//(002)L is formed after the migration of interface (002)D//(002)L·^1/2[100] and vice versa. These two kinds of interface appear alternatively. The jump and substitute of atoms selects the optimization way to induce the migration of interface during the phase transformation, and the number of atoms needing to jump during the migration is the least among all of the possible atom jump modes. 展开更多
关键词 phase transformation ordered domain interface interface migration microscopic phase-field Ni75AlxV25-x alloy
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A critical review on lead migration, transformation and emission control in Chinese coal-fired power plants 被引量:3
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作者 Yicheng Wang Hongyun Hu +5 位作者 Xinye Wang Huimin Liu Lu Dong Guangqian Luo Yongchun Zhao Hong Yao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第2期397-413,共17页
Coal is widely utilized as an important energy source,but coal-fired power plant was considered to be an important anthropogenic lead emission source.In the present study,the distribution characteristics of lead in co... Coal is widely utilized as an important energy source,but coal-fired power plant was considered to be an important anthropogenic lead emission source.In the present study,the distribution characteristics of lead in coal and combustion by-products are reviewed.Specifically,lead is mainly transferred to ash particles and the formation and migration mechanisms of particulate lead are summarized.Also,targeted measures are proposed to control the formation of fine particulate lead as well as to increase the removal efficiency during the low-temperature flue gas clean process.In detail,interactions between gaseous lead and some coal-bearing minerals or added adsorbents could obviously suppress the formation of fine particulate lead.On the other hand,some efforts(including promoting capture of fine particles,reducing resistivity of particles and strengthening the gas-liquid contact)could be made to improve the fine particulate lead removal capacity.Notably,the formation mechanism of fine particulate lead is still unclear due to the limitations of research methods.Some differences in the removal principles of fine particles and particulate lead make the lead emission precisely control a great challenge.Finally,the environmental potential risk of lead emission from flue gas and ash residues is addressed and further discussed. 展开更多
关键词 Coal combustion Particulate lead Formation and migration Removal strengthen Environmental risk
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Deep-water Natural Gas Differential Migration and Enrichment in East African Transform Continental Marginal Basins
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作者 CAI Jun HE Youbin +1 位作者 LIANG Jianshe GUO Rong 《Acta Geologica Sinica(English Edition)》 2025年第4期1105-1118,共14页
Compared to discrete continental marginal basins,the mechanisms of hydrocarbon migration and enrichment in transform continental marginal basins are poorly understood.In this study,we conducted a comprehensive analysi... Compared to discrete continental marginal basins,the mechanisms of hydrocarbon migration and enrichment in transform continental marginal basins are poorly understood.In this study,we conducted a comprehensive analysis of the main source rocks,reservoirs,and vertical migration pathways within the Rovuma(RB)and Tanzania(TB)basins in East Africa utilizing drilling,logging,seismic,and geochemical data.The results indicate that the enhanced preservation conditions of the Lower Jurassic source rocks in the southwest could lead to the discovery of large natural gas fields in the southern TB and RB.The primary reservoir is a deep-water turbidite sandstone.Due to topographic differences,the expanse of the turbidite sandstones in the RB is significantly larger than those in Tanzania.The main vertical migration pathways are the western boundary fault zone of the Kerimbas Graben(WBFZ)and the Seagap fault zone(SFZ).In the RB,natural gas migrates vertically along the WBFZ and preferentially accumulates in the deep-water turbidite sandstones of the footwall under the control of the fluid potential.Conversely,in the southern TB,the deep natural gas first migrates upward along the SFZ,then moves along the shallow branch faults in the sandstones on both sides of the SFZ. 展开更多
关键词 upstream exploration natural gas differential enrichment transform continental marginal basin fault activity DEEP-WATER Mozambique-Tanzania
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Study on Migration and Transformation Rule of Organic Pollutants (COD) in Aerated Zone
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作者 GaoTaizhong HuangQunxian +3 位作者 LiuYe QiPeng ZhangHuanzhen CaiHesheng 《Journal of China University of Geosciences》 SCIE CSCD 2003年第1期73-78,共6页
Collecting waste water with a certain c onc entration of organic pollutants COD (chemical oxygen demand), static adsorption, static biodegradation and dynamic soil column experiments were made in laborato ry, we rese... Collecting waste water with a certain c onc entration of organic pollutants COD (chemical oxygen demand), static adsorption, static biodegradation and dynamic soil column experiments were made in laborato ry, we researched migration and transformation of COD in aerated zone, and put f orward a mathematical model showing the process. The results show that adsorptio n of organism in aerated zone is linear, which is represented by Henry's law s =K dc+s d, adsorption coefficient K d=0.069 3; biodegradati on diagram accord basically with first order kinetics equation c=c 0e -K 1t , biodegradation coefficient K 1 = 0.049 9 d -1 ; dispersio n coefficient D= 0.002 42 m 2/d in experiments. The migration and transform ation of organic pollutants (COD) in aerated zone jointly result from many f actors such as dispersion, adsorption and biodegradation etc.. 展开更多
关键词 chemical oxygen demand of organic pollutants aerated zone migration and transformation.
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An Efficient Schema Transformation Technique for Data Migration from Relational to Column-Oriented Databases
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作者 Norwini Zaidi Iskandar Ishak +1 位作者 Fatimah Sidi Lilly Suriani Affendey 《Computer Systems Science & Engineering》 SCIE EI 2022年第12期1175-1188,共14页
Data transformation is the core process in migrating database from relational database to NoSQL database such as column-oriented database. However,there is no standard guideline for data transformation from relational... Data transformation is the core process in migrating database from relational database to NoSQL database such as column-oriented database. However,there is no standard guideline for data transformation from relational database toNoSQL database. A number of schema transformation techniques have been proposed to improve data transformation process and resulted better query processingtime when compared to the relational database query processing time. However,these approaches produced redundant tables in the resulted schema that in turnconsume large unnecessary storage size and produce high query processing timedue to the generated schema with redundant column families in the transformedcolumn-oriented database. In this paper, an efficient data transformation techniquefrom relational database to column-oriented database is proposed. The proposedschema transformation technique is based on the combination of denormalizationapproach, data access pattern and multiple-nested schema. In order to validate theproposed work, the proposed technique is implemented by transforming data fromMySQL database to MongoDB database. A benchmark transformation techniqueis also performed in which the query processing time and the storage size arecompared. Based on the experimental results, the proposed transformation technique showed significant improvement in terms query processing time and storagespace usage due to the reduced number of column families in the column-orienteddatabase. 展开更多
关键词 Data migration data transformation column-oriented database relational database big data
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In-situ observations on interphase boundary migration and grain growth during α/γ phase transformation in iron-4.2%Cr alloy
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作者 渡边忠雄 OBARA Kouichi TSUREKAWA Sadahiro 《材料与冶金学报》 CAS 2005年第2期91-91,共1页
In-situ observations on α/γ phase transformation were made to study the effects of grain boundary microstructures on the formation of a new phase and the migration of α/γ interphase boundary in an iron4. 2%Cr allo... In-situ observations on α/γ phase transformation were made to study the effects of grain boundary microstructures on the formation of a new phase and the migration of α/γ interphase boundary in an iron4. 2%Cr alloy. It was found that triple junctions with more random boundaries could be the primary nucleation sites for a new phase, while triple junctions with low angle or low ∑ coincidence boundaries did not play any role as preferential sites. The migration of α/γ interphase boundary during heating over the transformation temperature range showed the two stage behaviour characterized by a stage with a migration velocity of 0. 33-0. 75 mm/s and secondly by a stage with 3. 7-7. 6 mm/s. It was also found that abnormal grain growth and a high density of ∑3 coincidence boundaries could occur in a phase with bcc structure after cycling of α/γ phase transformation. A new mechanism of nucleation and growth of a new phase in α/γ phase transformation is proposed on the basis of roles of plane-matching interphase boundaries, as previously discussed on the origin of anisotropy of grain growth due to the migration of {110} plane-matching boundaries in Fe-3z%Si alloy. The most recent theoretical work on the distribution of plane-matching boundaries in solids with different crystal structures was found to be useful for the understanding of nucleation and growth during α/γ phase transformation. 展开更多
关键词 In-situ phase velocity stage effects crystal with random origin the range after new was more play over high MOST for The to DID BCC It be
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Research Progress of Migration and Transformation of Pharmaceuticals and Personal Care Products in Underground Environment
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作者 Zhang Fang Zhe Ma +1 位作者 Xinmin Xie Baizhong Yan 《Journal of Environmental Science and Engineering(B)》 2013年第12期736-740,共5页
With the increasing use of PPCPs (pharmaceuticals and personal care products), the impact caused by the accumulation of PPCPs on the environment has become increasingly serious and has attracted considerable attenti... With the increasing use of PPCPs (pharmaceuticals and personal care products), the impact caused by the accumulation of PPCPs on the environment has become increasingly serious and has attracted considerable attention. In the last 10 years, major studies on PPCPs have focused on the sources and analytical testing of concentrations in the environment. Afterward, studies have shifted to the transfer and transformation of PCPPs in the environment and to the environmental risk assessment of PPCPs. Studies on PPCPs in the underground environment have mainly focused on their adsorption, desorption, transfer, and transformation in the aeration and saturation zones. The main methods applied in these studies include indoor simulation experiments and outdoor sampling and testing. These studies have mainly considered one dimension, and most of them have concentrated only on the aeration or saturation zone. Therefore, the main developing directions of studies on PPCPs are the comprehensive study of the transfer and transform process from source to sink in the underground environment and the establishment of an effective and efficient PPCP detection system, 展开更多
关键词 PPCPS transfer and transformation POLLUTION underground environment.
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Research and Analysis on the College English Teaching Emphasis from the Cultural Migration and Transformation of Thinking Perspectives
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作者 Jinju Tan 《International Journal of Technology Management》 2016年第8期12-15,共4页
In this paper, we conduct research on the college English teaching emphasis from the cultural migration and transformation ofthinking perspectives. College English has long been in for the college English subject stat... In this paper, we conduct research on the college English teaching emphasis from the cultural migration and transformation ofthinking perspectives. College English has long been in for the college English subject status. However, college English as a multidisciplinary,interdisciplinary research in the field of discipline construction, it seems, are still stay in the linguistics, language knowledge in academiccharacteristics for its stage of development. Reform of basic college English teaching, the teacher is still teaching main body, is the teaching oflanguage knowledge, since teachers play an important role in language teaching, the teacher wants to penetrate cultural knowledge in teachingand we must strengthen their own culture. Under this basis, this paper proposes the novel ideals on the related issues that will be meaningful andinnovative. 展开更多
关键词 College English Teaching Emphasis Cultural migration Thinking Perspectives.
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