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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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Changes in border-associated macrophages after stroke: Single-cell sequencing analysis 被引量:1
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作者 Ning Yu Yang Zhao +3 位作者 Peng Wang Fuqiang Zhang Cuili Wen Shilei Wang 《Neural Regeneration Research》 2026年第1期346-356,共11页
Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macro... Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macrophages have been poorly understood and largely overlooked. However, a recent study reported that border-associated macrophages participate in stroke-induced inflammation, although many details and the underlying mechanisms remain unclear. In this study, we performed a comprehensive single-cell analysis of mouse border-associated macrophages using sequencing data obtained from the Gene Expression Omnibus(GEO) database(GSE174574 and GSE225948). Differentially expressed genes were identified, and enrichment analysis was performed to identify the transcription profile of border-associated macrophages. CellChat analysis was conducted to determine the cell communication network of border-associated macrophages. Transcription factors were predicted using the ‘pySCENIC' tool. We found that, in response to hypoxia, borderassociated macrophages underwent dynamic transcriptional changes and participated in the regulation of inflammatory-related pathways. Notably, the tumor necrosis factor pathway was activated by border-associated macrophages following ischemic stroke. The pySCENIC analysis indicated that the activity of signal transducer and activator of transcription 3(Stat3) was obviously upregulated in stroke, suggesting that Stat3 inhibition may be a promising strategy for treating border-associated macrophages-induced neuroinflammation. Finally, we constructed an animal model to investigate the effects of border-associated macrophages depletion following a stroke. Treatment with liposomes containing clodronate significantly reduced infarct volume in the animals and improved neurological scores compared with untreated animals. Taken together, our results demonstrate comprehensive changes in border-associated macrophages following a stroke, providing a theoretical basis for targeting border-associated macrophages-induced neuroinflammation in stroke treatment. 展开更多
关键词 border-associated macrophages CLODRONATE hypoxia ISCHEMIA-REPERFUSION ischemic stroke liposomes neuroinflammation single-cell sequencing analysis STAT3 tumor necrosis factor
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Comprehensive pan-cancer analysis of the receptor-interacting protein kinase family expression,genomic alterations,and functional implications
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作者 Wan-Rong Li Xin Li Jian Wang 《Life Research》 2026年第1期35-44,共10页
Background:Receptor-interacting protein kinases(RIPKs)regulate cell death,inflammation,and immune responses,yet their roles in cancer are not fully understood.This study investigates the expression,genomic alterations... Background:Receptor-interacting protein kinases(RIPKs)regulate cell death,inflammation,and immune responses,yet their roles in cancer are not fully understood.This study investigates the expression,genomic alterations,and functional implications of RIPK family members across various cancers.Methods:We collected multi-omics data from The Cancer Genome Atlas and other public databases,including gene expression,copy number variation(CNV),mutation,methylation,tumor mutation burden(TMB),and microsatellite instability(MSI).Differential expression and survival analyses were performed using DESeq2 and Cox proportional hazards models.CNV and mutation data were analyzed with GISTIC2 and Mutect2,and methylation data with the ChAMP package.Correlations with TMB and MSI were assessed using Pearson coefficients,and gene set enrichment analysis was conducted with the MSigDB Hallmark gene sets.Results:RIPK family members show significant differential expression in various cancers,with RIPK1 and RIPK4 frequently altered.Survival analysis reveals heterogeneous impacts on overall survival.CNV and mutation analyses identify high alteration frequencies for RIPK2 and RIPK7,affecting gene expression.RIPK1 and RIPK7 are hypermethylated in several cancers,inversely correlating with RIPK3 expression.RIPK1,RIPK2,RIPK5,RIPK6,and RIPK7 correlate positively with TMB,while RIPK3 shows negative correlations in some cancers.MSI analysis indicates associations with DNA mismatch repair.G ene set enrichment analysis highlights immune-related pathway enrichment for RIPK1,RIPK2,RIPK3,and RIPK6,and cell proliferation and DNA repair pathways for RIPK4 and RIPK5.RIPK family members showed heterogeneous alterations across cancers:for example,RIPK7 was mutated in up to~15%of u terine c orpus e ndometrial c arcinoma and l ung s quamous c ell c arcinoma cases,and RIPK1 and RIPK7 exhibited frequent promoter hypermethylation in multiple tumor types.Several genes displayed context-dependent associations with overall survival and with TMB/MSI.Conclusion:This pan-cancer analysis of the RIPK family reveals their diverse roles and potential as biomarkers and therapeutic targets.The findings emphasize the importance of RIPK genes in tumorigenesis and suggest context-dependent functions across cancer types.Further studies are needed to explore their mechanisms in cancer development and clinical applications. 展开更多
关键词 RIPK family pan-cancer analysis tumor mutation burden microsatellite instability gene set enrichment analysis
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Advanced isoconversional kinetic analysis of lepidolite sulfation product decomposition reactions for selectively extracting lithium
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作者 Yubo Liu Baozhong Ma +4 位作者 Jiahui Cheng Xiang Li Hui Yang Chengyan Wang Yongqiang Chen 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期217-227,共11页
The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.A... The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.Accordingly,comprehensive kinetic study by employing thermalgravimetric analysis at various heating rates was presented in this paper.Two main weight loss regions were observed during heating.The initial region corresponded to the dehydration of crystal water,whereas the subsequent region with overlapping peaks involved complex decomposition reactions.The overlapping peaks were separated into two individual reaction peaks and the activation energy of each peak was calculated using isoconversional kinetics methods.The activation energy of peak 1 exhibited a continual increase as the reaction conversion progressed,while that of peak 2 steadily decreased.The optimal kinetic models,identified as belonging to the random nucleation and subsequent growth category,provided valuable insights into the mechanism of the decomposition reactions.Furthermore,the adjustment factor was introduced to reconstruct the kinetic mechanism models,and the reconstructed models described the kinetic mechanism model more accurately for the decomposition reactions.This study enhanced the understanding of the thermochemical behavior and kinetic parameters of the lepidolite sulfation product decomposition reactions,further providing theoretical basis for promoting the selective extraction of lithium. 展开更多
关键词 LITHIUM LEPIDOLITE decomposition reactions KINETICS isoconversional analysis
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Global research status in the treatment of glaucoma:a systematic bibliometric analysis
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作者 Wen-Hui Liu Chang Shu +1 位作者 Bei-Di Jia Xiao-Rong Li 《International Journal of Ophthalmology(English edition)》 2026年第2期379-392,共14页
AIM:To present an overview of the research on global glaucoma treatment in the last decade in terms of publication year,journals,countries/regions,organizations,references,and keywords,to investigate the current resea... AIM:To present an overview of the research on global glaucoma treatment in the last decade in terms of publication year,journals,countries/regions,organizations,references,and keywords,to investigate the current research international trends and hot topics in this area.METHODS:Bibliometric analysis was conducted on 9128 articles in the Web of Science Core Collection(WoSCC;Clarivate)database.Quantitative and qualitative analysis was employed using VOSviewer(v1.6.18),Pajek(v1.0.0.0),and CiteSpace(v6.1.R2)software.RESULTS:The 9128 papers relating to glaucoma treatment were published from April 2013 to April 2023,of which 7482 articles(82%)were original research articles and 1464(18%)were review articles.The United States(2867)and Johns Hopkins University(166)were the most productive country and institution,respectively,but the University College London had the highest h-index(54).The Journal of Glaucoma was the most productive and Ophthalmology had the highest h-index compared with other journals.The Keywords of interest included treatment surgery,cyclophotocoagulation,minimally invasive glaucoma surgery(MIGS),trabeculectomy,baerveldt,epidemiology,medication adherence,nanoparticle,optical coherence tomography(OCT),gene therapy,and artificial intelligence(AI).Glaucoma surgery appeared as a current research hotspot through the analysis of keywords.CONCLUSION:This study provides insights into the research trends and potential research hotspots in the treatment of glaucoma.This will help researchers to evaluate research policies and to promote international cooperation. 展开更多
关键词 glaucoma treatment bibliometric analysis SURGERY minimally invasive glaucoma surgery NANOPARTICLE
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Combined Fault Tree Analysis and Bayesian Network for Reliability Assessment of Marine Internal Combustion Engine
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作者 Ivana Jovanović Çağlar Karatuğ +1 位作者 Maja Perčić Nikola Vladimir 《哈尔滨工程大学学报(英文版)》 2026年第1期239-258,共20页
This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for ... This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for identifying critical failure modes and their root causes,while BN introduces flexibility in probabilistic reasoning,enabling dynamic updates based on new evidence.This dual methodology overcomes the limitations of static FTA models,offering a comprehensive framework for system reliability analysis.Critical failures,including External Leakage(ELU),Failure to Start(FTS),and Overheating(OHE),were identified as key risks.By incorporating redundancy into high-risk components such as pumps and batteries,the likelihood of these failures was significantly reduced.For instance,redundant pumps reduced the probability of ELU by 31.88%,while additional batteries decreased the occurrence of FTS by 36.45%.The results underscore the practical benefits of combining FTA and BN for enhancing system reliability,particularly in maritime applications where operational safety and efficiency are critical.This research provides valuable insights for maintenance planning and highlights the importance of redundancy in critical systems,especially as the industry transitions toward more autonomous vessels. 展开更多
关键词 Fault tree analysis Bayesian network RELIABILITY REDUNDANCY Internal combustion engine
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Sensitivity analysis of rod rearrangement in criticality safety for PWR fuel assemblies under transportation accidents
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作者 Xin‑Ling Dai De‑Chang Cai +1 位作者 Yan‑Min Zhang Jin Cai 《Nuclear Science and Techniques》 2026年第1期263-282,共20页
To ensure the safe transportation of radioactive materials,numerous countries have established specific standards.For the transfer of fissile materials,it is imperative that the material within the packaging remains i... To ensure the safe transportation of radioactive materials,numerous countries have established specific standards.For the transfer of fissile materials,it is imperative that the material within the packaging remains in a subcritical state during routine,normal,and accidental transport conditions.In the event of an accident,the rods within the storage tank may become rearranged,introducing uncertainty that must be accounted for to ensure that criticality analysis results are conservative.Historically,this uncertainty was addressed overly conservatively due to limited research on non-uniform arrangement scenarios,which proved unsuitable for criticality safety analysis of spent fuel packages.This paper introduced three distinct methods to non-uniformly rearrange fuel rods—Uniform Arrangement by Blocks,Layer-by-Layer Determination,and Birdcage Deformation—and meticulously evaluates the influences of rod rearrangement on the effective multiplication factor of neutrons,k eff,utilizing the Monte Carlo method.Ultimately,this study presents a holistic method capable of encompassing the entire spectrum of potential effects stemming from the rearrangement of fuel rods during rods mispositioning accident.By augmenting the safety margin,this approach proves to be adeptly suited for the criticality safety analysis of nuclear fuel transport containers. 展开更多
关键词 Criticality safety analysis Fuel transports Rods mispositioning accident Non-uniform arrangement
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Heavy metal risks and policy analysis on using industrial waste salts for making value-added snow-melting agents
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作者 Yubiao Ma Jiaxin Yin +2 位作者 Yunfei Wang Lei Wang Jianxin Zhu 《Journal of Environmental Sciences》 2026年第1期756-766,共11页
Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may po... Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may pose certain environmental risks.Snow-melting agents and snow samples were collected and analyzed from highways,arterial roads,footbridges,and other locations in Beijing after the snowstorm in December 2023.It was found that the main component of snow-melting agents was sodium chloride with high concentrations of Cu,Mn,and Zn,which are not regulated in the current policies,despite the recent promotion of environmentally friendly snow-melting agents.The Pb,Zn and Cr contents of some snow samples exceeded the limitation value of surface water quality standards,potentially affecting the soil and water environment near roadsides,although the snow-melting agents comply with relevant standards,which indicates the policy gap in the management of recycled industrial salts.We reviewed and analyzed the relevant standards for snow-melting agents and industrial waste salts proposed nationally and internationally over the past 30 years.Through comparative analysis,we proposed relevant policy recommendations to the existing quality standards of snow-melting agents and the management regulations of industrial waste salts,and the formulation of corresponding usage strategies,aimed at reducing the potential environmental release of heavy metals from the use of snow-melting agents,thereby promoting more sustainable green urban development and environmentally sound waste management. 展开更多
关键词 Snow-melting agent Heavy metals Industrial waste salts recycled Comparative analysis
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Evaluation of the protective effects of Crocus sativus L.against cypermethrin induced reproductive toxicity in male rats through the Nrf2 pathway and in silico ADMET analysis
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作者 Fareena Tariq Farah Ijaz +9 位作者 Yasameen Hameed Jasim Farah Naz Channa Sohail Ahmed Ahmed Shandookh Hameed Sobia Alyas Ahmed Raheem Rayshan Tahira Bibi Nazima Yousaf Khan Sadia Bibi Jameel Ahmed Buzdar 《Traditional Medicine Research》 2026年第3期12-25,共14页
Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to i... Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to its therapeutic properties,but its exact role and molecular mechanisms in treatment of reproductive dysfunction remain unclear.Methods:During this study,36 rats were randomly divided into six groups(n=6):control,CYP-induced(60 mg/kg),standard(leuprolide 3 mg/kg)and three treatment groups receiving aqueous,ethanolic,and oil extracts(50 mg/kg or 20 mL/kg)for post-toxicity induction.Results:The finding represented that exposure of CYP significantly increased oxidative stress,disrupted testicular architecture,and markedly reduced testosterone levels(P<0.05).Importantly,Crocus sativus L.treatment alleviated these changes by increasing the expression of Nrf2(nuclear factor erythroid 2-related factor 2),restoring the activity of antioxidant enzymes,and enhancing testicular histomorphology.Surprisingly,molecular docking established a high binding affinity of Crocus sativus L.phytoconstituents such as gallic acid,cinnamic acid and quercetin to the Nrf2-Keap1 complex.It is worth noting that,Crocus sativus L.exhibited a high level of protection against reproductive toxicity caused by CYP in male rats,which was mediated by the activation of Nrf2 pathway,reduction of oxidative damage,and favorable ADMET characteristics.Conclusion:Notably,this research provides a more valid,safe,and effective method of developing new drugs for reproductive disorders,however,further investigation is needed to support the research findings and implement it in clinical practice. 展开更多
关键词 Crocus sativus L. CYPERMETHRIN male reproductive toxicity Nrf2 pathway in silico ADMET analysis
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Comparative Analysis on Fruit Qualities of 7 Litchi Varieties from Vietnam 被引量:1
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作者 张晓芳 刘光华 +5 位作者 罗心平 黄家雄 吕玉兰 娄予强 Nguyen Dinh Tue Tran Mihn Hoa 《Agricultural Science & Technology》 CAS 2010年第8期110-113,共4页
[Objective] The aim was to screen litchi varieties suitable for local production in Vietnam. [Method] The fruit botanical and quality characteristics of the seven litchi varieties introduced into Northern Mountainous ... [Objective] The aim was to screen litchi varieties suitable for local production in Vietnam. [Method] The fruit botanical and quality characteristics of the seven litchi varieties introduced into Northern Mountainous Agriculture and Forestry Science Institute of Vietnam Academy of Agriculture Sciences were compared and analyzed. [Result] Three varieties with good general qualities including Lai Phu Ho,Thach Binh and Hung Long which were suitable to be cultivated in the local area were selected. In addition,Phu Dong was the available,early-maturing germplasm resource. [Conclusion] This research will provide reference for litchi production and breeding in northern mountainous area. 展开更多
关键词 Vietnam litchi Comparative analysis of fruit qualities Variety selection
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Comparative Analysis on Fruit Qualities of Longan Varieties form Vietnam 被引量:1
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作者 张晓芳 罗心平 +4 位作者 刘光华 黄家雄 张惠云 NGUYEN Dinh Tue TRAN Mihn Hoa 《Agricultural Science & Technology》 CAS 2011年第10期1461-1463,共3页
[Objective] The aim was to screen longan varieties suitable for local production in Vietnam.[Method] The fruit botanical characteristics and quality characteristics of longan varieties introduced into Northern Mountai... [Objective] The aim was to screen longan varieties suitable for local production in Vietnam.[Method] The fruit botanical characteristics and quality characteristics of longan varieties introduced into Northern Mountainous Agriculture and Forestry Science Institute of Vietnam Academy of Agriculture Sciences were compared and analyzed.[Result] Two varieties with good general qualities including PMP6 and PHS1-1 which were suitable to be cultivated in the local area were selected.In addition,Phu Dong was the available processed germplasm resource.[Conclusion] This research will provide reference for longan production and breeding in Northern Mountainous. 展开更多
关键词 Vietnam longan Comparative analysis of fruit qualities Variety selection
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Element analysis method of concealed explosive based on TNA 被引量:2
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作者 Meng Huang Jian-Yu Zhu +1 位作者 Jun Wu Rui Li 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第1期19-25,共7页
The detection technology of concealed bulk explosives is related to social security and national defense construction and has important research significance. In this paper, an element analysis method of concealed exp... The detection technology of concealed bulk explosives is related to social security and national defense construction and has important research significance. In this paper, an element analysis method of concealed explosives based on thermal neutron analysis is proposed.This method could provide better reconstruction precision for hydrogen, carbon, and nitrogen ratios, making it possible to discriminate explosives from other compounds with the same elements but different proportions, as well as to identify the types of concealed bulk explosives. In this paper, the basic principles and mathematical model of this method are first introduced, and the calculation formula of the element number ratio(the ratio between the nucleus numbers of two different elements) of the concealed explosive is deduced. Second, a numerical simulation platform of this method was established based on the Monte Carlo JMCT code. By calibrating the absorption efficiencies of the explosive device to c rays, the element number ratios of a concealed explosive model under the irradiation of thermal neutrons were reconstructed from the neutron capture prompt c-ray spectrum. The reconstruction values were in good agreement with the actual values,which shows that this method has a high reconstruction precision of the element number ratio for concealed explosives. Lastly, it was demonstrated using the simulation study that this method can discriminate explosives,drugs, and common materials, with the capability of determining the existence of concealed bulk explosives and identifying explosive types. 展开更多
关键词 Concealed BULK EXPLOSIVE EXPLOSIVE type IDENTIFICATION tna ELEMENT NUMBER RATIO
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Prediction of land subsidence caused by groundwater exploitation in Hanoi, Vietnam, using multifactorial correlation analysis 被引量:7
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作者 Thinh Hong Phi Ludmila Aleksandrovna Strokova 《Research in Cold and Arid Regions》 CSCD 2013年第5期644-653,共10页
Multifactorial correlation analysis is a new method used to predict the land subsidence caused by groundwater exploitation This article introduces and applies the method to establish the function of the surface settle... Multifactorial correlation analysis is a new method used to predict the land subsidence caused by groundwater exploitation This article introduces and applies the method to establish the function of the surface settlement rate (Vs) and the function of the time-dependent surface settlement (St) caused by groundwater exploitation, based on data acquired at three land subsidence monitoring stations in the Hanoi area of Vietnam. Comparison with actual monitoring data indicates that the prediction results are relatively close to the monitoring data. From this, we conclude that multifactorial correlation analysis is a reliable method and can be used to predict future land subsidence caused by groundwater exploitation in Hanoi. 展开更多
关键词 land subsidence groundwater exploitation multifactorial correlation analysis surface settlement rate time-dependent settlement
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Isoconversional kinetic analysis of decomposition of bastnaesite concentrates with calcium hydroxide 被引量:5
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作者 Peng Cen Xue Bian Wenyuan Wu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第12期1361-1371,共11页
Isoconversional methods combined with thermogravimetry were applied to investigate the decomposition kinetics of bastnaesite concentrates with different amounts of calcium hydroxide added.The apparent activation energ... Isoconversional methods combined with thermogravimetry were applied to investigate the decomposition kinetics of bastnaesite concentrates with different amounts of calcium hydroxide added.The apparent activation energy was calculated,and the results indicate that the overall reaction involves more than one single step.The reaction with a lower content(<15 wt%)of calcium hydroxide can be divided into two steps,while the reaction with a higher content(>15 wt%)involves another step which denotes the decomposition of newly formed calcium carbonate during roasting.The activation energy increases with increasing amount of calcium hydroxide in the lower range(0-15 wt%).This is due to the resistance of calcium hydroxide to heat and mass transport,However,more calcium can promote the decomposition reaction more effectively and thus reduce the activation energy.Nonlinear fitting was performed by fitting the experimental data to Avrami-Erofeev model to determine the reaction model and pre-exponential factor.The theoretical models were proven to be reliable for kinetic prediction. 展开更多
关键词 BAStnaESITE Thermal analysis kinetics Isoconversional method Calcium hydroxide Rare earths
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A New Approach for Ranking Efficient Units in Data Envelopment Analysis and Application to a Sample of Vietnamese Agricultural Bank Branches 被引量:1
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作者 Nguyen Khac Minh Pham Van Khanh Pham Anh Tuan 《American Journal of Operations Research》 2012年第1期126-136,共11页
This paper proposes a new approach for ranking efficiency units in data envelopment analysis as a modification of the super-efficiency models developed by Tone [1]. The new approach based on slacks-based measure of ef... This paper proposes a new approach for ranking efficiency units in data envelopment analysis as a modification of the super-efficiency models developed by Tone [1]. The new approach based on slacks-based measure of efficiency (SBM) for dealing with objective function used to classify all of the decision-making units allows the ranking of all inefficient DMUs and overcomes the disadvantages of infeasibility. This method also is applied to rank super-efficient scores for the sample of 145 agricultural bank branches in Viet Nam during 2007-2010. We then compare the estimated results from the new SCI model and the exsisting SBM model by using some statistical tests. 展开更多
关键词 Data Envelopment analysis (DEA) Slacks-Based Measure of Efficiency (SBM) SCI Super-Efficient
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Scanning Analysis of REE in Bastnaesite with Synchrotron Radiation X-Ray Fluorescence Microprobe
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作者 安庆骧 王锐兵 +3 位作者 邓赛文 潘巨祥 吴应荣 吴澄宇 《Journal of Rare Earths》 SCIE EI CAS CSCD 1996年第4期308-311,共4页
The content of REE(La.Ce.Pr.Nd.Sm) in bastnaesite was measured by synchrotron radiation X-ray fluorescence microprobe.Scanning analysis makes use of excitation of the REE K lines between 33 and 50 keV.SR white beam fr... The content of REE(La.Ce.Pr.Nd.Sm) in bastnaesite was measured by synchrotron radiation X-ray fluorescence microprobe.Scanning analysis makes use of excitation of the REE K lines between 33 and 50 keV.SR white beam from a Wiggler source at the Beijing Electron Positron Collider(BEPC) of the National Laboratory,in order to excite the REE.The bastnaesite from the same mineral area was powdered to particle size≤300 mesh.It was then divided into two parts.One portion was used to be determined by XRF after depositing with oxalate and transforming into oxide.The other was pressed into disk without any binder as the reference sample.The weight and the diamieter of the disk were 15 g and 26 mm respectively. 展开更多
关键词 Synchrotron radiation X-ray fluomcence Rare earth analysis BAStnaESITE
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Korean Morphological Analysis for Korean-Vietnamese Statistical Machine Translation
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作者 Quang-Phuoc Nguyen Joon-Choul Shin Cheol-Young Ock 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第4期413-419,共7页
This paper describes the experiments with Korean-to-Vietnamese statistical machine translation(SMT). The fact that Korean is a morphologically complex language that does not have clear optimal word boundaries causes a... This paper describes the experiments with Korean-to-Vietnamese statistical machine translation(SMT). The fact that Korean is a morphologically complex language that does not have clear optimal word boundaries causes a major problem of translating into or from Korean. To solve this problem, we present a method to conduct a Korean morphological analysis by using a pre-analyzed partial word-phrase dictionary(PWD).Besides, we build a Korean-Vietnamese parallel corpus for training SMT models by collecting text from multilingual magazines. Then, we apply such a morphology analysis to Korean sentences that are included in the collected parallel corpus as a preprocessing step. The experiment results demonstrate a remarkable improvement of Korean-to-Vietnamese translation quality in term of bi-lingual evaluation understudy(BLEU). 展开更多
关键词 Factored translation models Korean-Vietnamese parallel corpus morphological analysis statistical machine translation(SMT)
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Analysis of Energy-saving Behavior among University Students in Vietnam
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作者 Naohiro Goto Shota Tokunaga +1 位作者 Dinh Thi Nga Van Ho Thi Thanh 《Journal of Environmental Science and Engineering(B)》 2016年第7期355-362,共8页
Currently, in the course of serious environmental problems where the cause is anthropogenic, such as global wanning, not only the technology and policies but also the promotions of pro-environmental behavior are requi... Currently, in the course of serious environmental problems where the cause is anthropogenic, such as global wanning, not only the technology and policies but also the promotions of pro-environmental behavior are required. However, previous studies reported a gap between high environmental awareness and behavior. So to promote this practice, it is necessary to clarify the determinants that lead to practice. Because of the rapid economic growth in developing countries, including Vietnam, pollution problems and energy consumption are of major importance. This study aims to propose methods to promote pro-environmental practices based on a questionnaire and statistical analysis that investigated university students in Vietnam's Ho Chi Minh city. From the factor analysis, in actions to do with the power-saving behavior of standby power and home electronics, and the use of air conditioning, four evaluation criteria including effectiveness, cost feasibility, convenience, and social norms are extracted. The covariance structure analysis showed that the evaluation of convenience represented the strongest causal relation to a given power-saving action, and the action, in turn, can lead to improvements in most practical activities so as to enhance their convenience. Finally, several methods to save energy are proposed based on the results of the questionnaire. 展开更多
关键词 Environmental behavior INTENTION factor analysis questionnaire investigation covariance structure analysis.
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Spatial-temporal Evolution Analysis on Land Use Multifunctionality in the China-Vietnam Border Area 被引量:1
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作者 HUANG Tianneng WANG Nian 《Chinese Geographical Science》 SCIE CSCD 2022年第6期995-1012,共18页
Exploring the spatial and temporal evolution characteristics of the border land use multifunctionality(LUMF)provides insights for taking advantage of border land use and optimizing border land use policies.Based on th... Exploring the spatial and temporal evolution characteristics of the border land use multifunctionality(LUMF)provides insights for taking advantage of border land use and optimizing border land use policies.Based on the improved Technique for Order Preference by Similarity to an Ideal Solution(TOPSIS)mode,this study identifies and evaluates the LUMFs in the China-Vietnam border area between 2000 and 2018 from the perspectives of agricultural production,social security,ecological service,landscape recreation,and national security.The results show that:1)The comprehensive land use functions in most counties and cities continued to be improved.2)The comprehensive land use function exhibits remarkable spatial divergence and aggregation characteristics.The high-value area of the agricultural production function and social security function evolves from the east to the west.In addition,the spatial evolution of ecological service function is complicated,without an obvious spatial divergence and aggregation pattern.The landscape recreation function shows different spatial differentiation characteristics in the early and middle stage,and forms a large cluster in the later stage.Finally,the spatial evolution pattern of the national security function is significant.3)Designing differentiated border land policies,improving border land use security,and establishing a long-term mechanism for ecological protection and ecological compensation can aid in optimizing the LUMF level in the border area. 展开更多
关键词 land use multifunctionality spatial-temporal evolution characteristics improved Technique for Order Preference by Similarity to an Ideal Solution(TOPSIS) spatial analysis China-Vietnam border area
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Geographic Object-Based Image Analysis of Changes in Land Cover in the Coastal Zones of the Red River Delta (Vietnam)
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作者 Simona Niculescu Chi Nguyen Lam 《Journal of Environmental Protection》 2019年第3期413-430,共18页
The majority of the population and economic activity of the northern half of Vietnam is clustered in the Red River Delta and about half of the country’s rice production takes place here. There are significant problem... The majority of the population and economic activity of the northern half of Vietnam is clustered in the Red River Delta and about half of the country’s rice production takes place here. There are significant problems associated with its geographical position and the intensive exploitation of resources by an overabundant population (population density of 962 inhabitants/km2). Some thirty years after the economic liberalization and the opening of the country to international markets, agricultural land use patterns in the Red River Delta, particularly in the coastal area, have undergone many changes. Remote sensing is a particularly powerful tool in processing and providing spatial information for monitoring land use changes. The main methodological objective is to find a solution to process the many heterogeneous coastal land use parameters, so as to describe it in all its complexity, specifically by making use of the latest European satellite data (Sentinel-2). This complexity is due to local variations in ecological conditions, but also to anthropogenic factors that directly and indirectly influence land use dynamics. The methodological objective was to develop a new Geographic Object-based Image Analysis (GEOBIA) approach for mapping coastal areas using Sentinel-2 data and Landsat 8. By developing a new segmentation, accuracy measure, in this study was determined that segmentation accuracies decrease with increasing segmentation scales and that the negative impact of under-segmentation errors significantly increases at a large scale. An Estimation of Scale Parameter (ESP) tool was then used to determine the optimal segmentation parameter values. A popular machine learning algorithms (Random Forests-RFs) is used. For all classifications algorithm, an increase in overall accuracy was observed with the full synergistic combination of available data sets. 展开更多
关键词 COASTAL ZONES Red River Delta Land COVER CHANGES Remote Sensing GEOGRAPHIC Object-Based Images analysis
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