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Maggot homogenate is associated with neural regeneration and wound healing in the rat
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作者 Zhen Zhang Shouyu Wang +3 位作者 Xiliang Tian Zexu Zhao Jianing Zhang Decheng Lv 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第8期623-629,共7页
BACKGROUND:Live delivery limits the clinical application of maggot therapy. To date in China, there are no in vivo reports regarding wound healing mechanisms of maggot therapy or the effects of maggot homogenate on w... BACKGROUND:Live delivery limits the clinical application of maggot therapy. To date in China, there are no in vivo reports regarding wound healing mechanisms of maggot therapy or the effects of maggot homogenate on wound nerve regeneration.OBJECTIVE:To avoid complications due to the use of live maggots, an aseptic maggot homogenate was applied. Substance P (SP) and gene protein product 9.5 expression in a cutaneous wound was analyzed to explore possible mechanisms of neural regeneration and wound healing in the rat.DESIGN, TIME AND SETTING:A random grouping and controlled animal study was performed at the laboratory of the Department of Orthopedic Surgery, First Affiliated Hospital, Dalian Medical University from August 2008 to April 2009.MATERIALS:Live maggots were cultured and provided by the laboratory of the Department of Orthopedic Surgery of the First Affiliated Hospital, Dalian Medical University, China.METHODS:A total of 48 adult rats were selected and two acute, full-thickness wounds (round, 1.5 cm diameter) were created on the back of each rat. The two wounds were randomly assigned to homogenate product and control groups. Following two-step disinfection of maggots, a homogenate was produced from 10 maggots and applied to the wound area in the homogenate product group, while the wounds in the control group were treated with normal saline alone.MAIN OUTCOME MEASURES:On days 1,3, 7, 10, 14, and 21 following injury, the wound tissue was excised. Histological examination of the wound was observed by hematoxylin and eosin staining or Masson's Trichrome staining. SP and protein gene product 9.5 expressions were examined by immunohistochemistry to evaluate wound neural regeneration.RESULTS:On days 7, 10, and 14, the rate of wound healing was significantly greater in the homogenate product group compared with the control group (P 〈 0.05), and homogenate healing was better than that seen in the control group. On days 3, 7, and 10, SP expression in cells and regenerative nerves was significantly greater in the homogenate product group compared with the control group (P 〈 0.05). On days 7 and 10, protein gene product 9.5 expression was detected in the regenerative nerve, and expression level was significantly greater in the homogenate product group compared with the control group (P 〈 0.05).CONCLUSION:Maggot homogenate resulted in upregulated SP and protein gene product 9.5 expressions, thereby promoting neural regeneration and wound healing. 展开更多
关键词 maggot therapy wound healing NEUROPEPTIDES neural regeneration rats MAGGOTS maggot homogenate
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Homogenate extraction technology of camptothecine and hydroxycamptothecin from Camptotheca acuminata leaves
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作者 SHI Wei-guo, ZU Yuan-gang, ZHAO Chun-jian, YANG Lei Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040, P.R.China 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A2期168-170,共3页
Camptothecine(CPT) and hydroxycamptothecin(HCPT), two kinds of anti-cancer alkaloids, were extracted from Camptotheca acuminata leaves using homogenate extraction technology under different conditions such as the rati... Camptothecine(CPT) and hydroxycamptothecin(HCPT), two kinds of anti-cancer alkaloids, were extracted from Camptotheca acuminata leaves using homogenate extraction technology under different conditions such as the ratio of material to liquid, ethanol concentration, and homogenate time.The optimum technology parameters for homogenate extraction of CPT and HCPT from C.acuminata leaves were determined as homogenate time at 8 min, ethanol concentration at 55% and the ratio of material to liquid at 1:15(g:mL).By using the optimized parameters, we obtained 0.639‰ extraction rate for CPT and 0.437‰ for HCPT.The extraction yields of CPT and HCPT extracted by homogenating technology were higher than those by other extractive methods, such as ultrasonic, reflux, shaking in water bath.It is concluded that the homogenate extraction technology was an efficient method for extracting CPT and HCPT from C.acuminata leaves, with characteristics of less extraction time and high yield. 展开更多
关键词 homogenate Camptotheca acuminata leaves camptothecine HYDROXYCAMPTOTHECIN
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Directional induction of dopaminergic neurons from neural stem cells using substantia nigra homogenates and basic fibroblast growth factor
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作者 Jintao Li Qi Yan +2 位作者 Yiliu Ma Zhongtang Feng Tinghua Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第7期511-516,共6页
To date, complex components of available reagents have been used for directional induction of neural stem cells into dopaminergic neurons, resulting in a poor ability to repeat experiments. This study sought to invest... To date, complex components of available reagents have been used for directional induction of neural stem cells into dopaminergic neurons, resulting in a poor ability to repeat experiments. This study sought to investigate whether a homogenate of the substantia nigra of adult rats and/or basic fibroblast growth factor could directionally induce neural stem cells derived from the subventricular zone of embryonic rats to differentiate into dopaminergic neurons. Tyrosine hydroxylase-positive cells were observed exclusively after induction with the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor for 48 hours in vitro. However, in the groups treated with homogenate supernatant or basic fibroblast growth factor alone, tyrosine hydroxylase expression was not observed. Moreover, the content of dopamine in the culture medium of subventricular zone neurons was significantly increased at 48 hours after induction with the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor. Experimental findings indicate that the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor could directionally induce neural stem cells derived from the subventricular zone of embryonic rats to differentiate into dopaminergic neurons in the substantia nigra with the ability to secrete dopamine. 展开更多
关键词 directional induction in vitro homogenate of substantia nigra basic fibroblast growth factor subventricular zone neural stem cells dopaminergic neurons
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Cryptococcal antigen testing of lung tissue homogenate improves pulmonary cryptococcosis diagnosis:Two case reports
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作者 Wei-Yi Wang Yu-Lu Zheng Li-Bin Jiang 《World Journal of Clinical Cases》 SCIE 2022年第12期3893-3898,共6页
BACKGROUND Pulmonary cryptococcosis(PC)is an opportunistic infectious disease of the respiratory system.Lung tissue biopsies,culture of respiratory samples(e.g.,sputum,lung tissue,pleural fluid,and bronchoalveolar lav... BACKGROUND Pulmonary cryptococcosis(PC)is an opportunistic infectious disease of the respiratory system.Lung tissue biopsies,culture of respiratory samples(e.g.,sputum,lung tissue,pleural fluid,and bronchoalveolar lavage fluid),and cryptococcal antigen(CrAg)testing are helpful for a definitive diagnosis.However,these tests are sometimes falsely negative.PC is often misdiagnosed or underdiagnosed owing to the absence of obvert symptoms,poor imaging specificity,and false-negative laboratory tests.CASE SUMMARY We report two female patients who underwent computed tomography-guided percutaneous needle pulmonary biopsy of a lung nodule for a confirmed diagnosis.In both patients,the CrAg test on the lung biopsy tissue homogenate was positive,while the serum CrAg test was negative.Combined with the lung tissue pathology,we made the diagnosis of PC.Antifungal therapy was effective in both patients.CONCLUSION Given the findings of our cases and the literature review,lung tissue homogenate CrAg testing can be helpful in improving the diagnosis of PC. 展开更多
关键词 Lung tissue homogenate Cryptococcal antigen test Pulmonary cryptococcosis Lung biopsy DIAGNOSIS Case report
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The Contribution of United States Aircraft Reconnaissance Data to the China Meteorological Administration Tropical Cyclone Intensity Data:An Evaluation of Homogeneity
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作者 Ming YING Xiaoqin LU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期639-654,共16页
This paper investigates the homogeneity of United States aircraft reconnaissance data and the impact of these data on the homogeneity of the tropical cyclone(TC)best track data for the seasons 1949-1987 generated by t... This paper investigates the homogeneity of United States aircraft reconnaissance data and the impact of these data on the homogeneity of the tropical cyclone(TC)best track data for the seasons 1949-1987 generated by the China Meteorological Administration(CMA).The evaluation of the reconnaissance data shows that the minimum central sea level pressure(MCP)data are relatively homogeneous,whereas the maximum sustained wind(MSW)data show both overestimations and spurious abrupt changes.Statistical comparisons suggest that both the reconnaissance MCP and MSW were well incorporated into the CMA TC best track dataset.Although no spurious abrupt changes were evident in the reconnaissance-related best track MCP data,two spurious changepoints were identified in the remainder of the best-track MCP data.Furthermore,the influence of the reconnaissance MSWs seems to extend to the best track MSWs unrelated to reconnaissance,which might reflect the optimistic confidence in making higher estimates due to the overestimated extreme wind“observations”.In addition,the overestimation of either the reconnaissance MSWs or the best track MSWs was greater during the early decades compared to later decades,which reflects the important influence of reconnaissance data on the CMA TC best track dataset.The wind-pressure relationship(WPR)used in the CMA TC best track dataset is also evaluated and is found to overestimate the MSW,which may lead to inhomogeneity within the dataset between the aircraft reconnaissance era and the satellite era. 展开更多
关键词 tropical cyclone intensity HOMOGENEITY best track aircraft reconnaissance
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Efficient Removal of Phosphate from Aqueous Solutions Using Corundum-hollow-spheres Supported Caclined Hydrotalcite Porous Thin Films
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作者 刘云才 ZHU Chen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期44-49,共6页
Phosphate was removed from aqueous environment by corundum-hollow-spheres supported caclined hydrotalcite (cHT) thin films. Mg-Al-CO3 hydrotalcite (HT) thin films were deposited on corundumhollow-sphere substrates by ... Phosphate was removed from aqueous environment by corundum-hollow-spheres supported caclined hydrotalcite (cHT) thin films. Mg-Al-CO3 hydrotalcite (HT) thin films were deposited on corundumhollow-sphere substrates by hydrothermal homogeneous precipitation at 120℃for 30-240 min and cHT thin films were obtained by annealing of the HT thin films at 500℃for 180 min. Their crystal phase, morphology and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).The results show that homogeneous, well-crystallized and hierarchical flower-like thin films were deposited firmly on the surface of the corundum. The mechanism of nucleation and growth of the HT thin films was fitted well with the anion coordination polyhedron growth unit model. To determine the absorption of phosphate by this adsorbent, different bed depth (10-30 cm) and flow rate (1.0-3.0 m L/min) were examined by column experiments. The highest removal efficiency of phosphate amounted to 98.5%under optimum condition (pH=7.2). The adsorption capacity increased as the bed depth increased and decreased as the flow rate increased. 展开更多
关键词 adsorption PHOSPHATE HYDROTALCITE corundum-hollow-sphere hydrothermal homogeneous precipitation thermal anneal
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Porous nanofibrous dressing enables mesenchymal stem cell spheroid formation and delivery to promote diabetic wound healing
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作者 Kexin Zhang Wenmin Zhang +4 位作者 Heng An Zhe Huang Yanzhen Wen Xiangyu Jiao Yongqiang Wen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期156-164,共9页
Delayed and nonhealing of diabetic wounds imposes substantial economic burdens and physical pain on patients.Mesenchymal stem cells(MSCs)promote diabetic wound healing.Particularly when MSCs aggregate into multicellul... Delayed and nonhealing of diabetic wounds imposes substantial economic burdens and physical pain on patients.Mesenchymal stem cells(MSCs)promote diabetic wound healing.Particularly when MSCs aggregate into multicellular spheroids,their therapeutic effect is enhanced.However,traditional culture platforms are inadequate for the efficient preparation and delivery of MSC spheroids,resulting in inefficiencies and inconveniences in MSC spheroid therapy.In this study,a three-dimensional porous nanofibrous dressing(NFD)is prepared using a combination of electrospinning and homogeneous freeze-drying.Using thermal crosslinking,the NFD not only achieves satisfactory elasticity but also maintains notable cytocompatibility.Through the design of its structure and chemical composition,the NFD allows MSCs to spontaneously form MSC spheroids with controllable sizes,serving as MSC spheroid delivery systems for diabetic wound sites.Most importantly,MSC spheroids cultured on the NFD exhibit improved secretion of vascular endothelial growth factor,basic fibroblast growth factor,and hepatocyte growth factor,thereby accelerating diabetic wound healing.The NFD provides a competitive strategy for MSC spheroid formation and delivery to promote diabetic wound healing. 展开更多
关键词 Electrospinning Homogenization Biomedical engineering Nanomaterials Stem cell spheroids Diabetic wound healing
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Formation and transformation of metastable LPSO building blocks clusters in Mg-Gd-Y-Zn-Zr alloys by spinodal decomposition and heterogeneous nucleation
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作者 Xin Zhao Zhong Yang +2 位作者 Jiachen Zhang Minxian Liang Liying Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期673-686,共14页
To study the formation and transformation mechanism of long-period stacked ordered(LPSO)structures,a systematic atomic scale analysis was conducted for the structural evolution of long-period stacked ordered(LPSO)stru... To study the formation and transformation mechanism of long-period stacked ordered(LPSO)structures,a systematic atomic scale analysis was conducted for the structural evolution of long-period stacked ordered(LPSO)structures in the Mg-Gd-Y-Zn-Zr alloy annealed at 300℃~500℃.Various types of metastable LPSO building block clusters were found to exist in alloy structures at different temperatures,which precipitate during the solidification and homogenization process.The stability of Zn/Y clusters is explained by the first principles of density functional theory.The LPSO structure is distinguished by the arrangement of its different Zn/Y enriched LPSO structural units,which comprises local fcc stacking sequences upon a tightly packed plane.The presence of solute atoms causes local lattice distortion,thereby enabling the rearrangement of Mg atoms in the different configurations in the local lattice,and local HCP-FCC transitions occur between Mg and Zn atoms occupying the nearest neighbor positions.This finding indicates that LPSO structures can generate necessary Schockley partial dislocations on specific slip surfaces,providing direct evidence of the transition from 18R to 14H.Growth of the LPSO,devoid of any defects and non-coherent interfaces,was observed separately from other precipitated phases.As a result,the precipitation sequence of LPSO in the solidification stage was as follows:Zn/Ycluster+Mg layers→various metastable LPSO building block clusters→18R/24R LPSO;whereas the precipitation sequence of LPSO during homogenization treatment was observed to be as follows:18R LPSO→various metastable LPSO building block clusters→14H LPSO.Of these,14H LPSO was found to be the most thermodynamically stable structure. 展开更多
关键词 LPSO Spinodal decomposition Homogenization treatment CLUSTERS Phase transformation
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Effect of carbon material and surfactant on ink property and resulting surface cracks of fuel-cell microporous layers
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作者 Zhekun Chen Weitong Pan +2 位作者 Longfei Tang Xueli Chen Fuchen Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期1-12,共12页
Ensuring the consistency of electrode structure in proton-exchange-membrane fuel cells is highly desired yet challenging because of wide-existing and unguided cracks in the microporous layer(MPL). The first thing is t... Ensuring the consistency of electrode structure in proton-exchange-membrane fuel cells is highly desired yet challenging because of wide-existing and unguided cracks in the microporous layer(MPL). The first thing is to evaluate the homogeneity of MPL with cracks quantitatively. This paper proposes the homogeneity index of a full-scale MPL with an area of 50 cm~2, which is yet to be reported in the literature to our knowledge. Besides, the effects of the carbon material and surfactant on the ink and resulting MPL structure have been studied. The ink with a high network development degree produces an MPL with low crack density, but the ink with high PDI produces an MPL with low crack homogeneity. The polarity of the surfactant and the non-polarity of polytetrafluoroethylene(PTFE) are not mutually soluble,resulting in the heterogeneous PTFE distribution. The findings of this study provide guidelines for MPL fabrication. 展开更多
关键词 Proton-exchange-membrane fuel cell Microporous layer Crack density Crack homogeneity Polytetrafluoroethylene distribution SURFACTANT
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Highly ordered crystallization of α-FAPbl_(3) films via homogeneous seeds for efficient perovskite solar cells
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作者 Guohui Luo Linfeng Zhang +11 位作者 Liyun Guo Xiuhong Geng Penghui Ren Yi Zhang Haihua Hu Xiaoping Wu Lingbo Xu Ping Lin Haiyan He Xuegong Yu Peng Wang Can Cui 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期625-634,共10页
Formamidine lead triiodide(FAPbI_(3))perovskites have become the most promising photovoltaic materials for perovskite solar cells with record power conversion efficiency(PCE).However,random nucleation,phase transition... Formamidine lead triiodide(FAPbI_(3))perovskites have become the most promising photovoltaic materials for perovskite solar cells with record power conversion efficiency(PCE).However,random nucleation,phase transition,and lattice defects are still the key challenges limiting the quality of FAPbI_(3) films.Previous studies show that the introduction or adding of seeds in the precursor is effective to promote the nucleation and crystallization of perovskite films.Nevertheless,the seed-assisted approach focuses on heterogeneous seeds or hetero-composites,which inevitably induce a lattice-mismatch,the genera-tion of strain or defects,and the phase segregation in the perovskite films.Herein,we first demonstrate that high-quality perovskite films are controllably prepared using α-and δ-phases mixed FAPbI_(3) micro-crystal as the homogeneous seeds with the one-step antisolvent method.The partially dissolved seeds with suitable sizes improve the crystallinity of the perovskite flm with preferable orientation,improved carrier lifetime,and increased carrier mobility.More importantly,the α-phase-containing seeds promote the formation of α-phase FAPbI_(3) films,leading to the reduction of residual lattice strain and the suppres-sion of I-ion migration.Besides,the adding of dimethyl 2,6-pyridine dicarboxylate(DPD)into the pre-cursor further suppresses the generation of defects,contributing to the PCE of devices prepared in air ambient being significantly improved to 23.75%,among the highest PCEs for fully air-processed FAPbI_(3) solar cells.The unpackaged target devices possess a high stability,maintaining 80%of the initial PCE under simulated solar illumination exceeding 800 h. 展开更多
关键词 Perovskite solar cells FAPbI_(3) Homogeneous seeds Strain Phase stability
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Structure,bioavailability and physicochemical properties of icariin-soymilk nanoparticle
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作者 Jinping Wang Lingrong Wen +4 位作者 Yueming Jiang Hong Zhu Weizheng Sun Guangyi Dai Bao Yang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期972-981,共10页
Soymilk is a natural nanocarrier.However,the performance of flavonoid-soymilk nano-complex remains unclear.In this work,icariin-soymilk nano-complexes(ISNCs)were successfully fabricated and characterized.The effects o... Soymilk is a natural nanocarrier.However,the performance of flavonoid-soymilk nano-complex remains unclear.In this work,icariin-soymilk nano-complexes(ISNCs)were successfully fabricated and characterized.The effects of high-pressure homogenization(HPH)treatment on structure and physicochemical properties of soymilk and nano-complexes were investigated.HPH treatment could significantly improve the surface hydrophobicity and interfacial activity of soymilk.The soymilk with HPH treatment could significantly improve the water solubility(20 folds),thermal stability and bioavailability of icariin.The highest encapsulation efficiency(93.28%),loading capacity(39.09μg/mg),ζ-potentia(absolute value,31.20 mV)and bioavailability(72.14%)were observed in HSI-200(200 bar of homogenization pressure).While HSI-500(500 bar of homogenization pressure)showed the smallest particle size(183.73 nm).ISNCs showed a rougher surface and an irregular lamellar structure with large amount of fine particles by using Cryo-SEM,suggesting that icariin was encapsulated in soymilk.These data supplied a novel strategy to improve the performance of icariin in functional foods. 展开更多
关键词 Encapsulation efficiency Flavonoid High pressure homogenization Loading capacity Nano-complex
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Modeling Method of C/C-ZrC Composites and Prediction of Equivalent Thermal Conductivity Tensor Based on Asymptotic Homogenization
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作者 Junpeng Lyu Hai Mei +2 位作者 Liping Zu Lisheng Liu Liangliang Chu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期391-410,共20页
This article proposes a modeling method for C/C-ZrC composite materials.According to the superposition of Gaussian random field,the original gray model is obtained,and the threshold segmentation method is used to gene... This article proposes a modeling method for C/C-ZrC composite materials.According to the superposition of Gaussian random field,the original gray model is obtained,and the threshold segmentation method is used to generate the C-ZrC inclusion model.Finally,the fiber structure is added to construct the microstructure of the three-phase plain weave composite.The reconstructed inclusions can meet the randomness of the shape and have a uniform distribution.Using an algorithm based on asymptotic homogenization and finite element method,the equivalent thermal conductivity prediction of the microstructure finite element model was carried out,and the influence of component volume fraction on material thermal properties was explored.The sensitivity of model parameters was studied,including the size,mesh sensitivity,Gaussian complexity,and correlation length of the RVE model,and the optimal calculation model was selected.The results indicate that the volume fraction of the inclusion phase has a significant impact on the equivalent thermal conductivity of the material.As the volume fraction of carbon fiber and ZrC increases,the equivalent thermal conductivity tensor gradually decreases.This model can be used to explore the impact of materialmicrostructure on the results,and numerical simulations have studied the relationship between structure and performance,providing the possibility of designing microstructure based on performance. 展开更多
关键词 3D reconstruction randomheterogeneous media microstructure asymptotic homogenization effective properties
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Catalytic effect in lithium metal batteries: From heterogeneous catalyst to homogenous catalyst
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作者 Haining Fan Xuan-Wen Gao +3 位作者 Hailong Xu Yichun Ding Shi-Xue Dou Wen-Bin Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期305-326,I0008,共23页
Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-elec... Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-electron,multi-step redox reaction associated with sluggish conversion kinetics,subsequently giving rise to a cascade of parasitic issues.In order to smooth reaction kinetics,catalysts are widely introduced to accelerate reaction rate via modulating the energy barrier.Over past decades,a large amount of research has been devoted to the catalyst design and catalytic mechanism exploration,and thus the great progress in electrochemical performance has been realized.Therefore,it is necessary to make a comprehensive review toward key progress in catalyst design and future development pathway.In this review,the basic mechanism of lithium metal batteries is provided along with corresponding advantages and existing challenges detailly described.The main catalysts employed to accelerate cathode reaction with emphasis on their catalytic mechanism are summarized as well.Finally,the rational design and innovative direction toward efficient catalysts are suggested for future application in metal-sulfur/gas battery and beyond.This review is expected to drive and benefit future research on rational catalyst design with multi-parameter synergistic impacts on the activity and stability of next-generation metal battery,thus opening new avenue for sustainable solution to climate change,energy and environmental issues,and the potential industrial economy. 展开更多
关键词 Energy storage and conversion Metal battery Sulfur battery Air battery Catalytic effect Heterogeneous catalyst Homogeneous catalyst
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COMPLETE KAHLER METRICS WITH POSITIVE HOLOMORPHIC SECTIONAL CURVATURES ON CERTAIN LINE BUNDLES(RELATED TO A COHOMOGENEITY ONE POINT OF VIEW ON A YAU CONJECTURE)
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作者 段晓曼 关庄丹 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期78-102,共25页
In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strateg... In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strategy to a famous Yau conjecture with a co-homogeneity one geometry. 展开更多
关键词 Kahler Metrics complete Riemannian metrics open complex manifolds holomorphic bisectional curvature C*bundle almost homogeneous manifolds
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Adaptive detection of range-spread targets in homogeneous and partially homogeneous clutter plus subspace interference
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作者 JIAN Tao HE Jia +3 位作者 WANG Bencai LIU Yu XU Congan XIE Zikeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期43-54,共12页
Adaptive detection of range-spread targets is considered in the presence of subspace interference plus Gaussian clutter with unknown covariance matrix.The target signal and interference are supposed to lie in two line... Adaptive detection of range-spread targets is considered in the presence of subspace interference plus Gaussian clutter with unknown covariance matrix.The target signal and interference are supposed to lie in two linearly independent subspaces with deterministic but unknown coordinates.Relying on the two-step criteria,two adaptive detectors based on Gradient tests are proposed,in homogeneous and partially homogeneous clutter plus subspace interference,respectively.Both of the proposed detectors exhibit theoretically constant false alarm rate property against unknown clutter covariance matrix as well as the power level.Numerical results show that,the proposed detectors have better performance than their existing counterparts,especially for mismatches in the signal steering vectors. 展开更多
关键词 adaptive detection subspace interference constant false alarm rate Gradient test partially homogeneous environment
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Unraveling the Rheology of Nanocellulose Aqueous Suspensions:A Comprehensive Study on Biomass-Derived Nanofibrillated Cellulose
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作者 Mingyue Miao Fei Wang +6 位作者 Qing Li Longchen Tao Chenchen Dai Yu Liu Shujuan Han Wenshuai Chen Ping Lu 《Journal of Renewable Materials》 EI CAS 2024年第3期443-455,共13页
The rheological properties of nanocellulose aqueous suspensions play a critical role in the development of nanocellulose-based bulk materials.High-crystalline,high-aspect ratio,and slender nanofibrillated cellulose(NF... The rheological properties of nanocellulose aqueous suspensions play a critical role in the development of nanocellulose-based bulk materials.High-crystalline,high-aspect ratio,and slender nanofibrillated cellulose(NFC)were extracted from four biomass resources.The cellulose nanofibrils and nanofibril bundles formed inter-connected networks in the NFC aqueous suspensions.The storage moduli of the suspensions with different concentrations were higher than their corresponding loss moduli.As the concentration increased,the storage and loss modulus of NFC dispersion increased.When the shear rate increased to a certain value,there were differences in the changing trend of the rheological behavior of NFC aqueous suspensions derived from different biomass resources and the suspensions with different solid concentrations.NFC dispersion’s storage and loss modulus increased when the temperature rose to nearly 80℃.We hope this study can deepen the understanding of the rheological properties of NFC colloids derived from different biomass resources. 展开更多
关键词 Biomass resources nanofibrillated cellulose high-pressure homogenizer SUSPENSION rheology properties
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A New Distribution Method for Wet Steam Injection Optimization
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作者 Jingjing Gao Xingkai Zhang 《Fluid Dynamics & Materials Processing》 EI 2024年第1期109-126,共18页
A new approach and a new related distribution system are proposed to address the issue of uneven steam injection caused by the different suction capacities of the used wells during the application of steam“stimulatio... A new approach and a new related distribution system are proposed to address the issue of uneven steam injection caused by the different suction capacities of the used wells during the application of steam“stimulation”methods for enhanced oil recovery.The new distribution system consists of a swirler,spiral dividing baffles,and critical flow nozzles.Numerical simulations are used to analyze the flow-field and degree of steam homogeneity obtained with such an approach.The results indicate that a higher inlet pressure leads to better results.Additionally,the internal flow field becomes more stable,and the deviation from an even distribution reduces to±4.0%even when the resistance of each branch is inconsistent.Furthermore,field tests have yielded satisfactory results. 展开更多
关键词 Cyclical steam stimulation homogeneous distribution gas-liquid two-phase flow critical flow nozzle
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Chemically Radiative MHD Flow of a Micropolar Nanofluid over a Stretching/ Shrinking Sheet with a Heat Source or Sink
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作者 Parakapali Roja Shaik Mohammed Ibrahim +1 位作者 Thummala Sankar Reddy Giulio Lorenzini 《Fluid Dynamics & Materials Processing》 EI 2024年第2期257-274,共18页
This study examines the behavior of a micropolar nanofluidflowing over a sheet in the presence of a transverse magneticfield and thermal effects.In addition,chemical(first-order homogeneous)reactions are taken into accoun... This study examines the behavior of a micropolar nanofluidflowing over a sheet in the presence of a transverse magneticfield and thermal effects.In addition,chemical(first-order homogeneous)reactions are taken into account.A similarity transformation is used to reduce the system of governing coupled non-linear partial differ-ential equations(PDEs),which account for the transport of mass,momentum,angular momentum,energy and species,to a set of non-linear ordinary differential equations(ODEs).The Runge-Kutta method along with shoot-ing method is used to solve them.The impact of several parameters is evaluated.It is shown that the micro-rota-tional velocity of thefluid rises with the micropolar factor.Moreover,the radiation parameter can have a remarkable influence on theflow and temperature profiles and on the angular momentum distribution. 展开更多
关键词 Chemical(first order homogeneous)reaction MAGNETOHYDRODYNAMICS MICROPOLAR NANOFLUID stretching/shrinking sheet heat source
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Integrated multi-scale approach combining global homogenization and local refinement for multi-field analysis of high-temperature superconducting composite magnets
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作者 Hanxiao GUO Peifeng GAO Xingzhe WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期747-762,共16页
Second-generation high-temperature superconducting(HTS)conductors,specifically rare earth-barium-copper-oxide(REBCO)coated conductor(CC)tapes,are promising candidates for high-energy and high-field superconducting app... Second-generation high-temperature superconducting(HTS)conductors,specifically rare earth-barium-copper-oxide(REBCO)coated conductor(CC)tapes,are promising candidates for high-energy and high-field superconducting applications.With respect to epoxy-impregnated REBCO composite magnets that comprise multilayer components,the thermomechanical characteristics of each component differ considerably under extremely low temperatures and strong electromagnetic fields.Traditional numerical models include homogenized orthotropic models,which simplify overall field calculation but miss detailed multi-physics aspects,and full refinement(FR)ones that are thorough but computationally demanding.Herein,we propose an extended multi-scale approach for analyzing the multi-field characteristics of an epoxy-impregnated composite magnet assembled by HTS pancake coils.This approach combines a global homogenization(GH)scheme based on the homogenized electromagnetic T-A model,a method for solving Maxwell's equations for superconducting materials based on the current vector potential T and the magnetic field vector potential A,and a homogenized orthotropic thermoelastic model to assess the electromagnetic and thermoelastic properties at the macroscopic scale.We then identify“dangerous regions”at the macroscopic scale and obtain finer details using a local refinement(LR)scheme to capture the responses of each component material in the HTS composite tapes at the mesoscopic scale.The results of the present GH-LR multi-scale approach agree well with those of the FR scheme and the experimental data in the literature,indicating that the present approach is accurate and efficient.The proposed GH-LR multi-scale approach can serve as a valuable tool for evaluating the risk of failure in large-scale HTS composite magnets. 展开更多
关键词 epoxy-impregnated high-temperature superconducting(HTS)magnet multi-scale method global homogenization(GH) local refinement(LR) multi-field analysis
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Numerical Sensitivity Studies on Effects of Ice Nucleating Processes on Electrification in Thunderstorms
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作者 师正 曲凯悦 +5 位作者 李璐滢 管啸林 孙京 崔雪东 胡佳瑞 吴子珉 《Journal of Tropical Meteorology》 SCIE 2024年第2期149-167,共19页
This study employed numerical simulations to explore the impact of varying ice nucleation processes on the microphysics and electrification within thunderstorm clouds.A two-dimensional cumulus model,incorporating both... This study employed numerical simulations to explore the impact of varying ice nucleation processes on the microphysics and electrification within thunderstorm clouds.A two-dimensional cumulus model,incorporating both noninductive and inductive charge separation schemes,was utilized.The findings revealed that the freezing nucleation mechanism significantly influenced the microphysical development,electrification,and charge structure of thunderstorms.Homogeneous freezing generated a large quantity of small ice crystals near the cloud tops,which were primarily responsible for the development of positive charge regions through a non-inductive charging process.Conversely,heterogeneous freezing resulted in larger ice crystals,enhancing graupel formation and leading to a more rapid and intense charge separation rate of around-15°C.Ice crystals formed heterogeneously and charged negatively during the development stage,resulting in an inverted dipole charge structure.When both immersion and homogeneous freezing processes were considered,the competition between these two distinct freezing processes resulted in reduced cloud water content and weaker electrification.Under conditions of low cloud water content at lower storm levels,graupel particles were negatively charged through non-inductive charging,causing the charge structure to quickly revert to a normal dipole structure. 展开更多
关键词 homogeneous freezing heterogeneous freezing immersion freezing non-inductive charging charge structure
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