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Tuning the solubility of polysulfides for constructing practical lithium-sulfur battery
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作者 Jiapeng Li Jianlong Cong +3 位作者 Haijin Ji Ting Shi Lixia Yuan Yunhui Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期611-617,I0013,共8页
Li-S batteries are regarded as one of the most promising candidates for next-generation battery systems with high energy density and low cost.However,the dissolution-precipitation reaction mechanism of the sulfur(S)ca... Li-S batteries are regarded as one of the most promising candidates for next-generation battery systems with high energy density and low cost.However,the dissolution-precipitation reaction mechanism of the sulfur(S)cathode enhances the kinetics of the redox processes of the insulating sulfu r,which also arouses the notorious shuttle effect,leading to serious loss of S species and corrosion of Li anode.To get a balance between the shuttle restraining and the kinetic property,a combined strategy of electrolyte regulation and cathode modification is proposed via introducing 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoroprpyl ether(HFE)instead of 1,2-dimethoxyethane(DME),and SeS_(7)instead of S_8.The introduction of HFE tunes the solvation structure of the LiTFSI and the dissolution of intermediate polysulfides with Se doping(LiPSSes),and optimize the interface stability of the Li anode simultaneously.The minor Se substitution compensates the decrease in kinetic due to the decreased solubility of LiPSs.In this way,the Li-SeS_(7)batteries deliver a reversible capacity of 1062 and 1037 mAh g^(-1)with 2.0 and 5.5 mg SeS_(7)cm^(-2)loading condition,respectively.Besides,an electrolyte-electrode loading model is established to explain the relationship between the optimal electrolyte and cathode loading.It makes more sense to guide the electrolyte design for practical Li-S batteries. 展开更多
关键词 Li-S batteries Lithium polysulfides solubility Shuttle effect Interface Se doping
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Theoretical analysis of hydrogen solubility in direct coal liquefaction solvents
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作者 Xiaobin Zhang Aoqi Wang +1 位作者 Xingbao Wang Wenying Li 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期187-197,共11页
The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimiz... The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimization and reactor design can be established by analyzing the solubility of hydrogen in liquefaction solvents.Experimental studies of hydrogen solubility in liquefaction solvents are challenging due to harsh reaction conditions and complex solvent compositions.In this study,the composition and content of liquefied solvents were analyzed.As model compounds,hexadecane,toluene,naphthalene,tetrahydronaphthalene,and phenanthrene were chosen to represent the liquefied solvents in chain alkanes and monocyclic,bicyclic,and tricyclic aromatic hydrocarbons.The solubility of hydrogen X(mol/mol)in pure solvent components and mixed solvents(alkanes and aromatics mixed in proportion to the chain alkanes+bicyclic aromatic hydrocarbons,bicyclic saturated aromatic hydrocarbons+bicyclic aromatic hydrocarbons,and bicyclic aromatic hydrocarbons+compounds containing het-eroatoms composed of mixed components)are determined using Aspen simulation at temperature and pressure conditions of 373–523 K and 2–10 MPa.The results demonstrated that at high temperatures and pressures,the solubility of hydrogen in the solvent increases with the increase in temperature and pressure,with the pressure having a greater impact.Further-more,the results revealed that hydrogen is more soluble in straight-chain alkanes than in other solvents,and the solubility of eicosanoids reaches a maximum of 0.296.The hydrogen solubility in aromatic ring compounds decreased gradually with an increase in the aromatic ring number.The influence of chain alkanes on the solubility of hydrogen predominates in a mixture of solvents with different mixing ratios of chain alkanes and aromatic hydrocarbons.The solubility of hydrogen in mixed aromatic solvents is less than that in the corresponding single solvents.Hydrogen is less soluble in solvent compounds containing heteroatoms than in compounds without heteroatoms. 展开更多
关键词 Direct coal liquefaction Liquefaction solvents Process simulation Hydrogen solubility
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RETRACTED: Determination of the Mesalazine Solubility at Biorelevant Temperature
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作者 Ekin Güler Kader Poturcu +1 位作者 Elaheh Rahimpour Abolghasem Jouyban 《International Journal of Analytical Mass Spectrometry and Chromatography》 2024年第1期1-12,共14页
Short Retraction NoticeThis article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of ... Short Retraction NoticeThis article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused. The full retraction notice in PDF is preceding the original paper, which is marked "RETRACTED". 展开更多
关键词 MESALAZINE solubility Shake-Flask Method Biorelevant Temperature XRD
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Study of the Relationship Between New Ionic Interaction Parameters and Salt Solubility in Electrolyte Solutions Based on Molecular Dynamics Simulation
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作者 SUN Wenting HU Yangdong +5 位作者 ZHENG Jiahuan SUN Qichao Chen Xia DING Jiakun ZHANG Weitao WU Lianying 《Journal of Ocean University of China》 CAS CSCD 2024年第2期467-476,共10页
Studying the relationship between ionic interactions and salt solubility in seawater has implications for seawater desalination and mineral extraction.In this paper,a new method of expressing ion-to-ion interaction is... Studying the relationship between ionic interactions and salt solubility in seawater has implications for seawater desalination and mineral extraction.In this paper,a new method of expressing ion-to-ion interaction is proposed by using molecular dynamics simulation,and the relationship between ion-to-ion interaction and salt solubility in a simulated seawater water-salt system is investigated.By analyzing the variation of distance and contact time between ions in an electrolyte solution,from both spatial and temporal perspectives,new parameters were proposed to describe the interaction between ions:interaction distance(ID),and interaction time ratio(ITR).The best correlation between characteristic time ratio and solubility was found for a molar ratio of salt-to-water of 10:100 with a correlation coefficient of 0.96.For the same salt,a positive correlation was found between CTR and the molar ratio of salt and water.For type 1-1,type 2-1,type 1-2,and type 2-2 salts,the correlation coefficients between CTR and solubility were 0.93,0.96,0.92,and 0.98 for a salt-to-water molar ratio of 10:100,respectively.The solubility of multiple salts was predicted by simulations and compared with experimental values,yielding an average relative deviation of 12.4%.The new ion-interaction parameters offer significant advantages in describing strongly correlated and strongly hydrated electrolyte solutions. 展开更多
关键词 molecular dynamics simulation interaction distance interaction time rate electrolyte aqueous solutions solubility
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Extraction of Acoustic Normal Mode Depth Functions Using Range-Difference Method with Vertical Linear Array Data
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作者 GAO Siyu LI Weilu +2 位作者 ZHANG Yinquan LI Xiaolei WANG Ning 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期871-882,共12页
Data-derived normal mode extraction is an effective method for extracting normal mode depth functions in the absence of marine environmental data.However,when the corresponding singular vectors become nonunique when t... Data-derived normal mode extraction is an effective method for extracting normal mode depth functions in the absence of marine environmental data.However,when the corresponding singular vectors become nonunique when two or more singular values obtained from the cross-spectral density matrix diagonalization are nearly equal,this results in unsatisfactory extraction outcomes for the normal mode depth functions.To address this issue,we introduced in this paper a range-difference singular value decomposition method for the extraction of normal mode depth functions.We performed the mode extraction by conducting singular value decomposition on the individual frequency components of the signal's cross-spectral density matrix.This was achieved by using pressure and its range-difference matrices constructed from vertical line array data.The proposed method was validated using simulated data.In addition,modes were successfully extracted from ambient noise. 展开更多
关键词 range difference depth function extraction normal mode
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Solubility determination and comparison ofβ-HMX and RDX in two binary mixed solvents(acetonitrile+water,nitric acid+water)
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作者 Yuehua Yao Fan Wang +3 位作者 Yinguang Xu Zishuai Xu Lizhen Chen Jianlong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期238-249,共12页
In order to remove hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX),the main impurity,in process of polymorphic transformation of octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),the solubility ofβ-HMX and RDX in a... In order to remove hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX),the main impurity,in process of polymorphic transformation of octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),the solubility ofβ-HMX and RDX in acetonitrile(ACN)+water in the temperature range of 288.15-333.15 K and in nitric acid(HNO_(3))+water in the temperature range of 298.15-333.15 K were measured by laser dynamic method.The results showed that the solubility of bothβ-HMX and RDX in binary mixed solvents increased monotonously as the temperature increase at a given solvent composition or with increasing of mole fraction of solvent(ACN and nitric acid).Solubility data were well correlated by the modified Apelblat equation,Jouyban-Acree model,Yaws equation and van't Hoff equation,and the Yaws equation achieved the best fitting results according to the relative error and the mean square error root.Furthermore,the solubility ofβ-HMX and RDX in binary mixed solvent was compared,based on the solubility difference and the solvent's own properties,the best separation degree ofβ-HMX and RDX was found when the mole fraction of nitric acid was 0.22 at room temperature,which provided data support for HMX crystallization in mixed solvent.The solubility differences between RDX andβ-HMX in mixed solvents were explained from the formation of intermolecular and intramolecular hydrogen bonds. 展开更多
关键词 solubility Octrahydro-1 3 5 7-tetranitro-1 3 5 7-tetrazocine Hexahydro-1 3 5-trinitro-1 3 5-triazine Separation Model Hydrogen bond
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Differential pressure difference based altitude control of a stratospheric satellite
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作者 陈丽 WANG Xiaoliang 《High Technology Letters》 EI CAS 2024年第1期1-12,共12页
An autonomous altitude adjustment system for a stratospheric satellite(StratoSat)platform is proposed.This platform consists of a helium balloon,a ballonet,and a two-way blower.The helium balloon generates lift to bal... An autonomous altitude adjustment system for a stratospheric satellite(StratoSat)platform is proposed.This platform consists of a helium balloon,a ballonet,and a two-way blower.The helium balloon generates lift to balance the platform gravity.The two-way blower inflates and deflates the ballonet to regulate the buoyancy.Altitude adjustment is achieved by tracking the differential pressure difference(DPD),and a threshold switching strategy is used to achieve blower flow control.The vertical acceleration regulation ability is decided not only by the blower flow rate,but also by the designed margin of pressure difference(MPD).Pressure difference is a slow-varying variable compared with altitude,and it is adopted as the control variable.The response speed of the actuator to disturbance can be delayed,and the overshoot caused by the large inertia of the platform is inhibited.This method can maintain a high tracking accuracy and reduce the complexity of model calculation,thus improving the robustness of controller design. 展开更多
关键词 stratospheric satellite(StratoSat) differential pressure difference(DPD) altitude adjustment threshold switching strategy margin of pressure difference(MPD)
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Study on sex differences and potential clinical value of threedimensional computerized tomography pelvimetry in rectal cancer patients
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作者 Xiao-Cong Zhou Fei-Yue Ke +2 位作者 Gaurav Dhamija Hao Chen Qiang Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期773-786,共14页
BACKGROUND Laparoscopic rectal cancer radical surgery is a complex procedure affected by various factors.However,the existing literature lacks standardized parameters for the pelvic region and soft tissues,which hampe... BACKGROUND Laparoscopic rectal cancer radical surgery is a complex procedure affected by various factors.However,the existing literature lacks standardized parameters for the pelvic region and soft tissues,which hampers the establishment of consistent conclusions.AIM To comprehensively assess 16 pelvic and 7 soft tissue parameters through computerized tomography(CT)-based three-dimensional(3D)reconstruction,providing a strong theoretical basis to address challenges in laparoscopic rectal cancer radical surgery.METHODS We analyzed data from 218 patients who underwent radical laparoscopic surgery for rectal cancer,and utilized CT data for 3D pelvic reconstruction.Specific anatomical points were carefully marked and measured using advanced 3D modeling software.To analyze the pelvic and soft tissue parameters,we emp-loyed statistical methods including paired sample t-tests,Wilcoxon rank-sum tests,and correlation analysis.RESULTS The investigation highlighted significant sex disparities in 14 pelvic bone parameters and 3 soft tissue parameters.Males demonstrated larger measurements in pelvic depth and overall curvature,smaller measurements in pelvic width,a larger mesorectal fat area,and a larger anterior-posterior abdominal diameter.By contrast,females exhibited wider pelvises,shallower depth,smaller overall curvature,and an increased amount of subcutaneous fat tissue.However,there were no significant sex differences observed in certain parameters such as sacral curvature height,superior pubococcygeal diameter,rectal area,visceral fat area,waist circumference,and transverse abdominal diameter.CONCLUSION The reconstruction of 3D CT data enabled accurate pelvic measurements,revealing significant sex differences in both pelvic and soft tissue parameters.This study design offer potential in predicting surgical difficulties and creating personalized surgical plans for male rectal cancer patients with a potentially“difficult pelvis”,ultimately improving surgical outcomes.Further research and utilization of these parameters could lead to enhanced surgical methods and patient care in laparoscopic rectal cancer radical surgery. 展开更多
关键词 Computerized tomography Rectal cancer Three-dimensional reconstruction PELVIMETRY Sex differences
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Analysis of Extended Fisher-Kolmogorov Equation in 2D Utilizing the Generalized Finite Difference Method with Supplementary Nodes
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作者 Bingrui Ju Wenxiang Sun +1 位作者 Wenzhen Qu Yan Gu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期267-280,共14页
In this study,we propose an efficient numerical framework to attain the solution of the extended Fisher-Kolmogorov(EFK)problem.The temporal derivative in the EFK equation is approximated by utilizing the Crank-Nicolso... In this study,we propose an efficient numerical framework to attain the solution of the extended Fisher-Kolmogorov(EFK)problem.The temporal derivative in the EFK equation is approximated by utilizing the Crank-Nicolson scheme.Following temporal discretization,the generalized finite difference method(GFDM)with supplementary nodes is utilized to address the nonlinear boundary value problems at each time node.These supplementary nodes are distributed along the boundary to match the number of boundary nodes.By incorporating supplementary nodes,the resulting nonlinear algebraic equations can effectively satisfy the governing equation and boundary conditions of the EFK equation.To demonstrate the efficacy of our approach,we present three numerical examples showcasing its performance in solving this nonlinear problem. 展开更多
关键词 Generalized finite difference method nonlinear extended Fisher-Kolmogorov equation Crank-Nicolson scheme
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Influences of clean fracturing fluid viscosity and horizontal in-situ stress difference on hydraulic fracture propagation and morphology in coal seam
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作者 Gang Wang Shuxin Wang +5 位作者 Yixin Liu Qiming Huang Shengpeng Li Shuliang Xie Jinye Zheng Jiuyuan Fan 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期159-175,共17页
The viscosity of fracturing fluid and in-situ stress difference are the two important factors that affect the hydraulic fracturing pressure and propagation morphology. In this study, raw coal was used to prepare coal ... The viscosity of fracturing fluid and in-situ stress difference are the two important factors that affect the hydraulic fracturing pressure and propagation morphology. In this study, raw coal was used to prepare coal samples for experiments, and clean fracturing fluid samples were prepared using CTAB surfactant. A series of hydraulic fracturing tests were conducted with an in-house developed triaxial hydraulic fracturing simulator and the fracturing process was monitored with an acoustic emission instrument to analyze the influences of fracturing fluid viscosity and horizontal in-situ stress difference on coal fracture propagation. The results show that the number of branched fractures decreased, the fracture pattern became simpler, the fractures width increased obviously, and the distribution of AE event points was concentrated with the increase of the fracturing fluid viscosity or the horizontal in-situ stress difference. The acoustic emission energy decreases with the increase of fracturing fluid viscosity and increases with the increase of horizontal in situ stress difference. The low viscosity clean fracturing fluid has strong elasticity and is easy to be compressed into the tip of fractures, resulting in complex fractures. The high viscosity clean fracturing fluids are the opposite. Our experimental results provide a reference and scientific basis for the design and optimization of field hydraulic fracturing parameters. 展开更多
关键词 Clean fracturing fluid Hydraulic fracturing VISCOSITY Horizontal in-situ stress difference Hydraulic fracture morphology Acoustic emission
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Stability and accuracy of central difference method for real-time dynamic substructure testing considering mass participation coefficient
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作者 Zheng Lichang Xu Guoshan +3 位作者 Yang Ge Wang Zhen Yang Kaibo Zheng Zhenyun 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期625-636,共12页
For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been investigated.Therefore,this study prop... For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been investigated.Therefore,this study proposes to investigate the stability and accuracy of the central difference method(CDM)for RTDST considering the specimen mass participation coefficient.First,the theory of the CDM for RTDST is presented.Next,the stability and accuracy of the CDM for RTDST considering the specimen mass participation coefficient are investigated.Finally,numerical simulations and experimental tests are conducted for verifying the effectiveness of the method.The study indicates that the stability of the algorithm is affected by the mass participation coefficient of the specimen,and the stability limit first increases and then decreases as the mass participation coefficient increases.In most cases,the mass participation coefficient will increase the stability limit of the algorithm,but in specific circumstances,the algorithm may lose its stability.The stability and accuracy of the CDM considering the mass participation coefficient are verified by numerical simulations and experimental tests on a three-story frame structure with a tuned liquid damper. 展开更多
关键词 real-time dynamic substructure testing central difference method STABILITY mass participation coefficient tuned liquid damper
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Solubility of iron(Ⅲ) and nickel(Ⅱ) acetylacetonates in supercritical carbon dioxide
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作者 Haixin Sun Jianlei Qi +4 位作者 Jianfei Sun Lin Li Kunpeng Yu Jintao Wu Jianzhong Yin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期29-34,共6页
As a common precursor for supercritical CO_(2)(scCO_(2))deposition techniques,solubility data of organometallic complexes in scCO_(2)is crucial for the preparation of nanocomposites.Recently,metal acetylacetonates hav... As a common precursor for supercritical CO_(2)(scCO_(2))deposition techniques,solubility data of organometallic complexes in scCO_(2)is crucial for the preparation of nanocomposites.Recently,metal acetylacetonates have shown great potential for the preparation of single-atom catalytic materials.In this study,the solubilities of iron(Ⅲ)acetylacetonate(Fe(acac)3)and nickel(Ⅱ)acetylacetonate(Ni(acac)2)were measured at the temperature from 313.15 to 333.15 K and in the pressure range of 9.5–25.2 MPa to accumulate new solubility data.Solubility was measured using a static weight loss method.The semi-empirical models proposed by Chrastil and Sung et al.were used to correlate the solubility data of Fe(acac)3 and Ni(acac)2.The equations obtained can be used to predict the solubility of the same system in the experimental range. 展开更多
关键词 Iron(III)acetylacetonate Nickel(II)acetylacetonate Supercritical carbon dioxide solubility measurement Correlation model Phase equilibrium
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Fuzzy Difference Equations in Diagnoses of Glaucoma from Retinal Images Using Deep Learning
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作者 D.Dorathy Prema Kavitha L.Francis Raj +3 位作者 Sandeep Kautish Abdulaziz S.Almazyad Karam M.Sallam Ali Wagdy Mohamed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期801-816,共16页
The intuitive fuzzy set has found important application in decision-making and machine learning.To enrich and utilize the intuitive fuzzy set,this study designed and developed a deep neural network-based glaucoma eye ... The intuitive fuzzy set has found important application in decision-making and machine learning.To enrich and utilize the intuitive fuzzy set,this study designed and developed a deep neural network-based glaucoma eye detection using fuzzy difference equations in the domain where the retinal images converge.Retinal image detections are categorized as normal eye recognition,suspected glaucomatous eye recognition,and glaucomatous eye recognition.Fuzzy degrees associated with weighted values are calculated to determine the level of concentration between the fuzzy partition and the retinal images.The proposed model was used to diagnose glaucoma using retinal images and involved utilizing the Convolutional Neural Network(CNN)and deep learning to identify the fuzzy weighted regularization between images.This methodology was used to clarify the input images and make them adequate for the process of glaucoma detection.The objective of this study was to propose a novel approach to the early diagnosis of glaucoma using the Fuzzy Expert System(FES)and Fuzzy differential equation(FDE).The intensities of the different regions in the images and their respective peak levels were determined.Once the peak regions were identified,the recurrence relationships among those peaks were then measured.Image partitioning was done due to varying degrees of similar and dissimilar concentrations in the image.Similar and dissimilar concentration levels and spatial frequency generated a threshold image from the combined fuzzy matrix and FDE.This distinguished between a normal and abnormal eye condition,thus detecting patients with glaucomatous eyes. 展开更多
关键词 Convolutional Neural Network(CNN) glaucomatous eyes fuzzy difference equation intuitive fuzzy sets image segmentation retinal images
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Exploring Phonetic Differences and Cross-Linguistic Influences: A Comparative Study of English and Mandarin Chinese Pronunciation Patterns
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作者 Than My Thi Duyen 《Open Journal of Applied Sciences》 2024年第7期1807-1822,共16页
Exploring the differences in phonemes and cross-linguistic influences, particularly by comparing the pronunciation patterns of English and Mandarin, is crucial for language learners. Such comparative studies can help ... Exploring the differences in phonemes and cross-linguistic influences, particularly by comparing the pronunciation patterns of English and Mandarin, is crucial for language learners. Such comparative studies can help learners better understand and overcome the pronunciation difficulties encountered during second language acquisition. English and Mandarin have significant differences in their vowel and consonant systems, tones, intonation, and syllable structures. A deep understanding of these differences allows learners to engage in targeted pronunciation training, reducing accent interference. This research provides guidance for improving language teaching methods, enabling teachers to design more effective pronunciation strategies and exercises based on the students’ native language backgrounds, thus enhancing learning outcomes. Additionally, cross-linguistic studies aid in improving speech recognition and conversion technologies, achieving higher accuracy and naturalness in multilingual speech processing systems. From a cultural exchange perspective, understanding and respecting the phonetic characteristics of different languages help to enhance the effectiveness and mutual understanding in cross-cultural communication. The comparative study of English and Mandarin pronunciation patterns not only provides a theoretical foundation for language education and technological applications but also promotes effective communication in multilingual environments. This thesis uses a comparative research method to elucidate the study of English and Mandarin pronunciation patterns. It begins with an analysis of the characteristics and similarities of the pronunciation patterns in both languages. The thesis then examines the differences between English and Mandarin pronunciation patterns through four aspects: the number and complexity of vowel phonemes, types and distribution of consonant phonemes, tones and stress, and intonation and phonetic phenomena. Finally, based on the comparative analysis of the differences, the thesis offers targeted policy recommendations for learning English and Mandarin. 展开更多
关键词 ENGLISH MANDARIN Pronunciation Patterns Phoneme differences
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Assessment of vegetation cover changes and the contributing factors in the Al-Ahsa Oasis using Normalized Difference Vegetation Index(NDVI)
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作者 Walid CHOUARI 《Regional Sustainability》 2024年第1期42-53,共12页
The abandonment of date palm grove of the former Al-Ahsa Oasis in the eastern region of Saudi Arabia has resulted in the conversion of delicate agricultural area into urban area.The current state of the oasis is influ... The abandonment of date palm grove of the former Al-Ahsa Oasis in the eastern region of Saudi Arabia has resulted in the conversion of delicate agricultural area into urban area.The current state of the oasis is influenced by both expansion and degradation factors.Therefore,it is important to study the spatiotemporal variation of vegetation cover for the sustainable management of oasis resources.This study used Landsat satellite images in 1987,2002,and 2021 to monitor the spatiotemporal variation of vegetation cover in the Al-Ahsa Oasis,applied multi-temporal Normalized Difference Vegetation Index(NDVI)data spanning from 1987 to 2021 to assess environmental and spatiotemporal variations that have occurred in the Al-Ahsa Oasis,and investigated the factors influencing these variation.This study reveals that there is a significant improvement in the ecological environment of the oasis during 1987–2021,with increase of NDVI values being higher than 0.10.In 2021,the highest NDVI value is generally above 0.70,while the lowest value remains largely unchanged.However,there is a remarkable increase in NDVI values between 0.20 and 0.30.The area of low NDVI values(0.00–0.20)has remained almost stable,but the region with high NDVI values(above 0.70)expands during 1987–2021.Furthermore,this study finds that in 1987–2002,the increase of vegetation cover is most notable in the northern region of the study area,whereas from 2002 to 2021,the increase of vegetation cover is mainly concentrated in the northern and southern regions of the study area.From 1987 to 2021,NDVI values exhibit the most pronounced variation,with a significant increase in the“green”zone(characterized by NDVI values exceeding 0.40),indicating a substantial enhancement in the ecological environment of the oasis.The NDVI classification is validated through 50 ground validation points in the study area,demonstrating a mean accuracy of 92.00%in the detection of vegetation cover.In general,both the user’s and producer’s accuracies of NDVI classification are extremely high in 1987,2002,and 2021.Finally,this study suggests that environmental authorities should strengthen their overall forestry project arrangements to combat sand encroachment and enhance the ecological environment of the Al-Ahsa Oasis. 展开更多
关键词 Normalized difference Vegetation Index(NDVI) Vegetation cover Ecological environment Land use and land cover(LULC) Urban expansion Al-Ahsa Oasis
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Preparation, characterization and evaluation of kaempferol phospholipid complex: Improvement of its solubility and biological effect
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作者 Dezhi Gao Honghui Zhao +4 位作者 Fengmao Zou Ming Yang Jing Wang Lina Fang Xu Zhao 《Journal of Polyphenols》 2024年第2期56-64,共9页
Kaempferol(KA),as one of the flavonoids,has extensive pharmacological properties.However,the poor solubility of KA severely limits its clinical application.In our study,the kaempferol phospholipid complex(KA-PC)has be... Kaempferol(KA),as one of the flavonoids,has extensive pharmacological properties.However,the poor solubility of KA severely limits its clinical application.In our study,the kaempferol phospholipid complex(KA-PC)has been prepared by solvent evaporation for the enhancement of the bioavailability of KA.KA-PC was verified by scanning electron microscope characterization methods.Drug loading,solubility and long-term stability were measured.The characterization results showed that KA-PC was formed through the intermolecular interaction between KA and phospholipids.The solubility of KA-PC in water was 189 times higher than that of KA,and the solubility in n-octanol was also significantly improved.Besides,pharmacodynamic studies showed that KA-PC can significantly reduce the level of serum uric acid in mice without causing renal injury.This study expanded the clinical application of KA by preparing KA-PC. 展开更多
关键词 KAEMPFEROL phospholipid complex solubility uric acid-lowering effect
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Analyzing the Differences in the Concepts of Love Between Korean and American Women Using the Female Characters in Kim Ji-young,Born in 1982 and The Sun Also Rises as Examples
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作者 Xiaoyi Yang 《Journal of Contemporary Educational Research》 2024年第2期112-116,共5页
This paper scrutinizes the differences in the conceptualization of love between Korean and American women.Grounded in an analysis of literary figures,Brett and Kim Ji-young,the study unravels the intricate interplay o... This paper scrutinizes the differences in the conceptualization of love between Korean and American women.Grounded in an analysis of literary figures,Brett and Kim Ji-young,the study unravels the intricate interplay of cultural,historical,and societal forces shaping these perspectives.The contrasting landscapes of the United States,driven by ideals of freedom and individualism,and Korea,entrenched in Confucian values and collectivism,serve as crucibles for forming women’s roles,self-perception,and societal expectations.The examination extends to communication styles,illuminating the directness of American expression versus Korea’s reliance on formalism.Through this exploration,the paper illustrates the profound impact of cultural contexts on the intricate tapestry of love,offering a nuanced understanding of divergent viewpoints within a global context. 展开更多
关键词 LOVE Cultural differences Women Society INDIVIDUALISM
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Solubility measurement,correlation and thermodynamic properties of 2,3,4-trichloro-1,5-dinitrobenzene in fifteen mono-solvents at temperatures from 278.15 to 323.15 K 被引量:1
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作者 Yun-Zhang Liu Lu-Yao Zhang +3 位作者 Dan He Li-Zhen Chen Zi-Shuai Xu Jian-Long Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期224-233,共10页
The solubility of 2,3,4-trichloro-1,5-dinitrobenzene(TCDNB) was measured by a laser dynamic method over the temperature range from 278.15 K to 323.15 K under 0.1 MPa in fifteen mono-solvents(methanol,ethanol,isopropan... The solubility of 2,3,4-trichloro-1,5-dinitrobenzene(TCDNB) was measured by a laser dynamic method over the temperature range from 278.15 K to 323.15 K under 0.1 MPa in fifteen mono-solvents(methanol,ethanol,isopropanol,n-butanol,toluene,dichloromethane,chloroform,tetrachloromethane,1,2-dichloroethane,acetone,ethyl acetate,acetonitrile,N-methylpyrrolidone(NMP),N,Ndimethylformamide dimethyl sulfoxide(DMF),dimethyl sulfoxide(DMSO).The solubility of TCDNB could be increased with increasing temperature in fifteen mono-solvents.TCDNB solubility is in the following order at 298.15 K:NMP>DMF>DMSO>toluene>acetone>ethyl acetate>dichloromethane>1,2-dich loroethane>chloroform>acetonitrile>tetrachloromethane>methanol>ethanol>n-butanol>isopropanol.The KAT-LSER model was used to investigate the solvent effect,which revealed that the hydrogen bond acidity of solvents has a greater effect on TCDNB solubility.The van't Hoff model,the modified Apelblat model,theλh model,and the non-random two liquid(NRTL)model were used to correlate the solubility of TCDNB.The calculated solubility data agreed well with the experimental data,and the modified Apelblat model fit best.Furthermore,the van't Hoff and Gibbs equations were also used to calculate the dissolution thermodynamic properties of TCDNB in various solvents.TCDNB dissolution could be an enthalpy-driven,non-spontaneous,and endothermic process in fifteen mono-solvents.The determination and fitting solubility of TCDNB,as well as the calculation of its thermodynamic properties,would be critical in the purification and crystallization of its preparation process research. 展开更多
关键词 2 3 4-Trichloro-1 5-dinitrobenzene(TCDNB) Solid-liquid equilibrium Laser dynamic method solubility model Thermodynamics properties
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Caloric restriction-mimetics for the reduction of heart failure risk in aging heart: with consideration of gender-related differences 被引量:1
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作者 Lei Pang Xi Jiang +6 位作者 Xin Lian Jie Chen Er-Fei Song Lei-Gang Jin Zheng-Yuan Xia Hai-Chun Ma Yin Cai 《Military Medical Research》 SCIE CAS CSCD 2023年第1期113-133,共21页
The literature is full of claims regarding the consumption of polyphenol or polyamine-rich foods that offer some protection from developing cardiovascular disease(CVD). This is achieved by preventing cardiac hypertrop... The literature is full of claims regarding the consumption of polyphenol or polyamine-rich foods that offer some protection from developing cardiovascular disease(CVD). This is achieved by preventing cardiac hypertrophy and protecting blood vessels through improving the function of endothelium. However, do these interventions work in the aged human hearts? Cardiac aging is accompanied by an increase in left ventricular hypertrophy, along with diastolic and systolic dysfunction. It also confers significant cardiovascular risks for both sexes. The incidence and prevalence of CVD increase sharply at an earlier age in men than women. Furthermore, the patterns of heart failure differ between sexes, as do the lifetime risk factors. Do caloric restriction(CR)-mimetics, rich in polyphenol or polyamine, delay or reverse cardiac aging equally in both men and women? This review will discuss three areas:(1) mechanisms underlying age-related cardiac remodeling;(2) gender-related differences and potential mechanisms underlying diminished cardiac response in older men and women;(3) we select a few polyphenol or polyamine rich compounds as the CRmimetics, such as resveratrol, quercetin, curcumin, epigallocatechin gallate and spermidine, due to their capability to extend health-span and induce autophagy. We outline their abilities and issues on retarding aging in animal hearts and preventing CVD in humans. We discuss the confounding factors that should be considered for developing therapeutic strategies against cardiac aging in humans. 展开更多
关键词 Cardiovascular disease Cardiac aging Caloric restriction Gender difference Caloric restriction-mimetics Dietary compounds Clinical application
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New Finite Difference Mapped WENO Schemes with Increasingly High Order of Accuracy 被引量:1
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作者 Jun Zhu Jianxian Qiu 《Communications on Applied Mathematics and Computation》 2023年第1期64-96,共33页
In this paper,a new type of finite difference mapped weighted essentially non-oscillatory(MWENO)schemes with unequal-sized stencils,such as the seventh-order and ninthorder versions,is constructed for solving hyperbol... In this paper,a new type of finite difference mapped weighted essentially non-oscillatory(MWENO)schemes with unequal-sized stencils,such as the seventh-order and ninthorder versions,is constructed for solving hyperbolic conservation laws.For the purpose of designing increasingly high-order finite difference WENO schemes,the equal-sized stencils are becoming more and more wider.The more we use wider candidate stencils,the bigger the probability of discontinuities lies in all stencils.Therefore,one innovation of these new WENO schemes is to introduce a new splitting stencil methodology to divide some fourpoint or five-point stencils into several smaller three-point stencils.By the usage of this new methodology in high-order spatial reconstruction procedure,we get different degree polynomials defined on these unequal-sized stencils,and calculate the linear weights,smoothness indicators,and nonlinear weights as specified in Jiang and Shu(J.Comput.Phys.126:202228,1996).Since the difference between the nonlinear weights and the linear weights is too big to keep the optimal order of accuracy in smooth regions,another crucial innovation is to present the new mapping functions which are used to obtain the mapped nonlinear weights and decrease the difference quantity between the mapped nonlinear weights and the linear weights,so as to keep the optimal order of accuracy in smooth regions.These new MWENO schemes can also be applied to compute some extreme examples,such as the double rarefaction wave problem,the Sedov blast wave problem,and the Leblanc problem with a normal CFL number.Extensive numerical results are provided to illustrate the good performance of the new finite difference MWENO schemes. 展开更多
关键词 Finite difference Mapped WENO scheme Mapping function Mapped nonlinear weight Unequal-sized stencil Extreme example
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