期刊文献+
共找到46篇文章
< 1 2 3 >
每页显示 20 50 100
Potential-dependent insights into the origin of high ammonia yield rate on copper surface via nitrate reduction:A computational and experimental study
1
作者 Yangge Guo Nannan Sun +5 位作者 Liuxuan Luo Xiaojing Cheng Xueying Chen Xiaohui Yan Shuiyun Shen Junliang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期272-281,共10页
Focusing on revealing the origin of high ammonia yield rate on Cu via nitrate reduction(NO3RR),we herein applied constant potential method via grand-canonical density functional theory(GC-DFT)with implicit continuum s... Focusing on revealing the origin of high ammonia yield rate on Cu via nitrate reduction(NO3RR),we herein applied constant potential method via grand-canonical density functional theory(GC-DFT)with implicit continuum solvation model to predict the reaction energetics of NO3RR on pure copper surface in alkaline media.The potential-dependent mechanism on the most prevailing Cu(111)and the minor(100)and(110)facets were established,in consideration of NO_(2)_(−),NO,NH_(3),NH_(2)OH,N_(2),and N_(2)O as the main products.The computational results show that the major Cu(111)is the ideal surface to produce ammonia with the highest onset potential at 0.06 V(until−0.37 V)and the highest optimal potential at−0.31 V for ammonia production without kinetic obstacles in activation energies at critical steps.For other minor facets,the secondary Cu(100)shows activity to ammonia from−0.03 to−0.54 V with the ideal potential at−0.50 V,which requires larger overpotential to overcome kinetic activation energy barriers.The least Cu(110)possesses the longest potential range for ammonia yield from−0.27 to−1.12 V due to the higher adsorption coverage of nitrate,but also with higher tendency to generate di-nitrogen species.Experimental evaluations on commercial Cu/C electrocatalyst validated the accuracy of our proposed mechanism.The most influential(111)surface with highest percentage in electrocatalyst determined the trend of ammonia production.In specific,the onset potential of ammonia production at 0.1 V and emergence of yield rate peak at−0.3 V in experiments precisely located in the predicted potentials on Cu(111).Four critical factors for the high ammonia yield and selectivity on Cu surface via NO3RR are summarized,including high NO3RR activity towards ammonia on the dominant Cu(111)facet,more possibilities to produce ammonia along different pathways on each facet,excellent ability for HER inhibition and suitable surface size to suppress di-nitrogen species formation at high nitrate coverage.Overall,our work provides comprehensive potential-dependent insights into the reaction details of NO3RR to ammonia,which can serve as references for the future development of NO3RR electrocatalysts,achieving higher activity and selectivity by maximizing these characteristics of copper-based materials. 展开更多
关键词 Nitrate reduction to ammonia Copper surface Density functional theory Constant electrode potential method experimental validation
下载PDF
An internal ballistic model of electromagnetic railgun based on PFN coupled with multi-physical field and experimental validation
2
作者 Benfeng Gu Haiyuan Li Baoming Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期254-261,共8页
To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore damage.In this paper,a three-dime... To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore damage.In this paper,a three-dimensional numerical model of the augmented railgun with four parallel unconventional rails is introduced to simulate the internal ballistic process and realize the multi-physics field coupling calculation of the rail gun,and a test experiment of a medium-caliber electromagnetic launcher powered by pulse formation network(PFN)is carried out.Various test methods such as spectrometer,fiber grating and high-speed camera are used to test several parameters such as muzzle initial velocity,transient magnetic field strength and stress-strain of rail.Combining the simulation results and experimental data,the damage condition of the contact surface is analyzed. 展开更多
关键词 Internal ballistic modeling Electromagnetic rail gun Multi-physics field coupling experimental validation PFN
下载PDF
Adaptive Robust Servo Control for Vertical Electric Stabilization System of Tank and Experimental Validation
3
作者 Darui Lin Xiuye Wang +1 位作者 Yimin Wang Guolai Yang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期326-342,共17页
A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevaryin... A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevarying but bounded uncertainty within the vertical electric stabilization system:model parameter uncertainty and uncertain nonlinearity.First,the vertical electric stabilization system is constructed as an uncertain nonlinear dynamic system that can reflect the practical mechanics transfer process of the system.Second,the dynamical equation in the form of state space is established by designing the angular tracking error.Third,the comprehensive parameter of system uncertainty is designed to estimate the most conservative effects of uncertainty.Finally,an adaptive robust servo control which can effectively handle the combined effects of complex nonlinearity and uncertainty is proposed.The feasibility of the proposed control strategy under the practical physical condition is validated through the tests on the experimental platform.This paper pioneers the introduction of the internal nonlinearity and uncertainty of the vertical electric stabilization system into the settlement of the tracking stability control problem,and validates the advanced servo control strategy through experiment for the first time. 展开更多
关键词 Adaptive robust servo control experimental validation Nonlinearity compensation System uncertainty Vertical electric stabilization system
下载PDF
Potential application of Nardostachyos Radix et Rhizoma-Rhubarb for the treatment of diabetic kidney disease based on network pharmacology and cell culture experimental verification
4
作者 Meng-Ying Che Ling Yuan +6 位作者 Jiao Min Duo-Jie Xu Dou-Dou Lu Wen-Jing Liu Kai-Li Wang Yan-Yan Wang Yi Nan 《World Journal of Diabetes》 SCIE 2024年第3期530-551,共22页
BACKGROUND Diabetic kidney disease(DKD)is one of the serious complications of diabetes mellitus,and the existing treatments cannot meet the needs of today's patients.Traditional Chinese medicine has been validated... BACKGROUND Diabetic kidney disease(DKD)is one of the serious complications of diabetes mellitus,and the existing treatments cannot meet the needs of today's patients.Traditional Chinese medicine has been validated for its efficacy in DKD after many years of clinical application.However,the specific mechanism by which it works is still unclear.Elucidating the molecular mechanism of the Nardostachyos Radix et Rhizoma-rhubarb drug pair(NRDP)for the treatment of DKD will provide a new way of thinking for the research and development of new drugs.AIM To investigate the mechanism of the NRDP in DKD by network pharmacology combined with molecular docking,and then verify the initial findings by in vitro experiments.METHODS The Traditional Chinese Medicine Systems Pharmacology(TCMSP)database was used to screen active ingredient targets of NRDP.Targets for DKD were obtained based on the Genecards,OMIM,and TTD databases.The VENNY 2.1 database was used to obtain DKD and NRDP intersection targets and their Venn diagram,and Cytoscape 3.9.0 was used to build a"drug-component-target-disease"network.The String database was used to construct protein interaction networks.Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis and Gene Ontology analysis were performed based on the DAVID database.After selecting the targets and the active ingredients,Autodock software was used to perform molecular docking.In experimental validation using renal tubular epithelial cells(TCMK-1),we used the Cell Counting Kit-8 assay to detect the effect of NRDP on cell viability,with glucose solution used to mimic a hyperglycemic environment.Flow cytometry was used to detect the cell cycle progression and apoptosis.Western blot was used to detect the protein expression of STAT3,p-STAT3,BAX,BCL-2,Caspase9,and Caspase3.RESULTS A total of 10 active ingredients and 85 targets with 111 disease-related signaling pathways were obtained for NRDP.Enrichment analysis of KEGG pathways was performed to determine advanced glycation end products(AGEs)-receptor for AGEs(RAGE)signaling as the core pathway.Molecular docking showed good binding between each active ingredient and its core targets.In vitro experiments showed that NRDP inhibited the viability of TCMK-1 cells,blocked cell cycle progression in the G0/G1 phase,and reduced apoptosis in a concentrationdependent manner.Based on the results of Western blot analysis,NRDP differentially downregulated p-STAT3,BAX,Caspase3,and Caspase9 protein levels(P<0.01 or P<0.05).In addition,BAX/BCL-2 and p-STAT3/STAT3 ratios were reduced,while BCL-2 and STAT3 protein expression was upregulated(P<0.01).CONCLUSION NRDP may upregulate BCL-2 and STAT3 protein expression,and downregulate BAX,Caspase3,and Caspase9 protein expression,thus activating the AGE-RAGE signaling pathway,inhibiting the vitality of TCMK-1 cells,reducing their apoptosis.and arresting them in the G0/G1 phase to protect them from damage by high glucose. 展开更多
关键词 Nardostachyos Radix et Rhizoma-rhubarb Diabetic kidney disease Molecular docking Network pharmacology experimental validation
下载PDF
Prediction of ground-borne vibration induced by impact pile driving:numerical approach and experimental validation
5
作者 A.Colaço P.Alves Costa +2 位作者 C.Ferreira C.Parente J.Fernandez-Ruiz 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第4期921-935,共15页
Deep foundations are currently used in engineering practice to solve problems caused by weak geotechnical characteristics of the ground.Impact pile driving is an interesting and viable solution from economic and techn... Deep foundations are currently used in engineering practice to solve problems caused by weak geotechnical characteristics of the ground.Impact pile driving is an interesting and viable solution from economic and technical points of view.However,it is necessary to ensure that the environmental drawbacks,namely ground-borne vibration,are adequately met.For this purpose,the authors propose an axisymmetric finite element method-perfectly matched layer(FEM-PML)approach,where the nonlinear behavior of the soil is addressed through an equivalent linear methodology.Given the complexity of the problem,an experimental test site was developed and fully characterized.The experimental work comprised in-situ and laboratory soil characterization,as well as the measurement of vibrations induced during pile driving.The comparison between experimental and numerical results demonstrated a very good agreement,from which it can be concluded that the proposed numerical approach is suitable for the prediction of vibrations induced by impact pile driving.The experimental database is available as supplemental data and may be used by other researchers in the validation of their prediction models. 展开更多
关键词 pile driving ground-borne vibrations numerical modeling experimental validation
下载PDF
Experimental Study of a Modified Icaro Solar Dryer: The Case of Coffee Drying
6
作者 Auguste Oscar Mackpayen Aloys Martial Ekoe A. Akata +1 位作者 Vinci De Dieu Bokoyo Barandja Kossi Napo 《Journal of Power and Energy Engineering》 2023年第7期36-48,共13页
Food losses in the developing country are thought to be 50% of the fruits and vegetables grown and 25% of harvested food grain. Food preservation can reduce wastage of a harvest surplus, allow storage for food shortag... Food losses in the developing country are thought to be 50% of the fruits and vegetables grown and 25% of harvested food grain. Food preservation can reduce wastage of a harvest surplus, allow storage for food shortages, and in some cases facilitate export to high-value markets. Drying is one of the oldest methods of food preservation. Drying makes produce lighter, smaller, and less likely to spoil and helps to minimize the moisture content in coffee beans as high moisture content during storage is certain to ruin the taste and appearance of coffee. This work presents the results of an experimental study of forced convection drying of coffee cherries in a modified Icaro solar dryer. The study aims to validate the numerical models developed for further research. The experimental tests envisaged also aim to determine the mass loss curves of the product by fixing or calculating its initial mass (1 kg), its initial water content (70%), the ambient temperature, the drying airflow (0.02 m<sup>3.</sup>s<sup>-1</sup> to 0.09 m<sup>3.</sup>s<sup>-1</sup>) and the exchange coefficients. The influence of these aerothermal parameters on the drying time of a most commercialized coffee variety (Robusta) was studied. Finally, the results revealed an increase in the efficiency of the heat transfer air and a reduction in the water content of the coffee cherry from 70% to 9.87%, after 30.2 hours. 展开更多
关键词 Solar Dryer Icaro experimental Validation Moisture Content COFFEE Tem-perature
下载PDF
A Train-Bridge Dynamic Interaction Analysis Method and Its Experimental Validation 被引量:16
7
作者 Nan Zhang Yuan Tian He Xia 《Engineering》 SCIE EI 2016年第4期528-536,共9页
The train-bridge dynamic interaction problem began with the development of railway technology, and requires an evaluation method for bridge design in order to ensure the safety and stability of the bridge and the runn... The train-bridge dynamic interaction problem began with the development of railway technology, and requires an evaluation method for bridge design in order to ensure the safety and stability of the bridge and the running train. This problem is studied using theoretical analysis, numerical simulation, and experimental study. In the train-bridge dynamic interaction system proposed in this paper, the train vehicle model is established by the rigid-body dynamics method, the bridge model is established by the finite element method, and the wheel/rail vertical and lateral interaction are simulated by the corresponding assumption and the Kalker linear creep theory, respectively. Track irregularity, structure deformation, wind load, collision load, structural damage, foundation scouring, and earthquake action are regarded as the excitation for the system. The train-bridge dynamic interaction system is solved by inter-history iteration. A case study of the dynamic response of a CRH380BL high-speed train running through a standard-design bridge in China is discussed. The dynamic responses of the vehicle and of the bridge subsystems are obtained for speeds ranging from 200 km-b-1 to 400 km.h-1, and the vibration mechanism are analyzed. 展开更多
关键词 Train-bridge dynamic interaction Wheel/rail relationship Inter-history iteration Field measurement experimental validation
下载PDF
Analysis of the cracks formation on surface of extruded magnesium rod based on numerical modeling and experimental verification 被引量:9
8
作者 Hongjun HU Dingfei ZHANG +1 位作者 Fusheng PAN Mingbo YANG 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2009年第5期353-364,共12页
To reduce the surface cracks of extrusion rod for AZ31 magnesium caused by nonhomogeneous metal flow in extrusion process, 3D computer finite element (FE) simulations of extruding a wrought magnesium alloy AZ31 into... To reduce the surface cracks of extrusion rod for AZ31 magnesium caused by nonhomogeneous metal flow in extrusion process, 3D computer finite element (FE) simulations of extruding a wrought magnesium alloy AZ31 into rods have been performed and the results have been verified in extrusion experiments under identical conditions. The tendency to generate the dead zone is decreased by employing the die angle 60° at the cone-shaped die comparing with the die angle 180°. The surface additional tensile stresses of the rod at the die exit are decreased greatly so that the surface cracks caused are avoided by using the die angle 60°. The extrusion die with die angle 180° would increase the higher temperature rise and possibility of crack formation on the rod surface that caused by die angle 60° and temperature rise decrease tensile strength of the AZ31 rod. The experimental results show that die angle 180° could cause continuous cracks on the surface of the extruded rod. The extrusion force required is reduced approximately 15 ton by employing the die angle 60°. Theoretical results obtained by the DeformTM-3D simulation agreed well with the experiments. The obtained results provide the fundamental and also practical guidelines for the design and correction of dies to produce magnesium rod with good surface quality. 展开更多
关键词 EXTRUSION Finite element Magnesium alloy Cracks experimental validation
下载PDF
Research Progress in Digging and Validation of miRNA Target Genes Using Experimental Methods 被引量:1
9
作者 Luo Xiao Bai Xi +4 位作者 Cai Hua Ji Wei Liu Xin Tang Li-li Zhu Yan-ming 《Journal of Northeast Agricultural University(English Edition)》 CAS 2012年第2期86-96,共11页
MicroRNAs (miRNAs) are a group of regulatory RNAs that regulate gene expression post-transcriptionally by the degradation or translational inhibition of their target messenger RNAs (mRNAs). Regulation is accomplis... MicroRNAs (miRNAs) are a group of regulatory RNAs that regulate gene expression post-transcriptionally by the degradation or translational inhibition of their target messenger RNAs (mRNAs). Regulation is accomplished when the 22-25 nucleotide miRNAs bind to complementary sequences in the 3'-untranslated regions (UTR). One barrier to miRNA research is to find target genes. Although computational target predictions have shed light on important aspects of microRNA target recognition, questions remain concerning the rates of false positives. In addition, we do not completely understand how microRNAs can recognize and regulate their targets. As such, experimental positive predictions and allow for an unbiased stu ap dy proaches are required, which can reflect in vivo processes, eliminating false of microRNA target recognition. In this review, we summarized experimental approaches that have been described for the identification and validation of mRNA targets associated with specific miRNAs. 展开更多
关键词 MIRNA TARGET experimental validation
下载PDF
Experimental validation method of elastic thin rod model for simulating the motional cable harness
10
作者 王春生 刘检华 +1 位作者 宁汝新 陈涛 《Journal of Beijing Institute of Technology》 EI CAS 2012年第2期192-197,共6页
To analyze the spring disturbance torque caused by motionai cable harness in a stabilized platform, the Kirchhoff theory based cable harness model has been previously developed to dynamically simulate the motional cab... To analyze the spring disturbance torque caused by motionai cable harness in a stabilized platform, the Kirchhoff theory based cable harness model has been previously developed to dynamically simulate the motional cable harness. In this paper, this model was validated by comparing the simulation results with the experiment results ( both the spring force and the deformed profile of the motional cable harness). In the experiment, a special optical measuring instrument based on binocular vision was developed and the motion and deformation of cable harness were measured. A simpli- fied stabilized platform system was constructed, and the absolute value of spring disturbance force during the motion of this simplified frame was obtained by using a force gauge (0. 02 N precision). The physical parameters of experimental specimen were also measured. The experimental and simulated results showed good agreement. These results should be useful for better motional cable harness layout design and reliable evaluation of the spring disturbance torque. 展开更多
关键词 experimental validation method binocular vision motional cable simulation Kirchhoffrod
下载PDF
The BOUT Project; Validation and Benchmark of BOUT Code and Experimental Diagnostic Tools for Fusion Boundary Turbulence
11
作者 徐学桥 《Plasma Science and Technology》 SCIE EI CAS CSCD 2001年第5期959-964,共6页
A boundary plasma turbulence code BOUT is presented. The preliminary encour- aging results have been obtained when comparing with probe measurements for a typical Ohmic discharge in HT-7 tokamak. The validation and be... A boundary plasma turbulence code BOUT is presented. The preliminary encour- aging results have been obtained when comparing with probe measurements for a typical Ohmic discharge in HT-7 tokamak. The validation and benchmark of BOUT code and experimental diagnostic tools for fusion boundary plasma turbulence is proposed. 展开更多
关键词 The BOUT Project Validation and Benchmark of BOUT Code and experimental Diagnostic Tools for Fusion Boundary Turbulence mode SOL
下载PDF
Understanding the alkyl effect of geminal dinitropropyl ester energetic plasticizers on hydroxyl terminated polybutadiene(HTPB):Simultaneous tuning on low temperature behavior and processability 被引量:1
12
作者 Baodong Zhao Yinglei Wang +3 位作者 Fulei Gao Yajing Liu Weixiao Liu Feng Ding 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期364-371,共8页
Geminal dinitropropyl ester plasticizers(DNPEPs) possess excellent energetic performances which provide good potentials as insensitive plasticizer. In this study, we design and synthesize DNPEPs with different alkane ... Geminal dinitropropyl ester plasticizers(DNPEPs) possess excellent energetic performances which provide good potentials as insensitive plasticizer. In this study, we design and synthesize DNPEPs with different alkane chain parts, and systematically investigate their structure-property relationships.Results show that DNPEPs have impact sensitivities all higher than 25.2 J, thermal decomposition temperatures all higher than 254 ℃, and glass transition temperatures(T_(g)) lower than-90 ℃.Furthermore, the effects of DNPEPs as plasticizer are studied on hydroxyl terminated polybutadiene(HTPB) in detail, including the viscosity, glass transition temperatures and others. It is noteworthy that 2,2-dinitropropyl nonanoate(DNPNc) among these DNPEPs exhibits the most expected simultaneous tuning effects on both viscosity and T_(g) of HTPB systems, providing favorable potentials to replace the conventional plastizers as dioctyl sebacate(DOS) in the HTPB based propellants and explosives. 展开更多
关键词 Molecular simulation experimental validation Preparation Energetic plasticizer Glass transition temperature Viscosity
下载PDF
Synthesizing and characterizing the magnetic EDTA/chitosan/CeZnO nanocomposite for simultaneous treating of chromium and phenol in an aqueous solution
13
作者 Masoumeh Sheikh Hosseini Lori Mohammad Delnavaz Hoda Khoshvaght 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期76-88,共13页
A new magnetic nanocomposite chitosan/EDTA/CeZnO(MEC-CeZnO)is synthesized as an efficient and eco-friendly bio-compound for the removal of chromium Cr(VI)metal ions and phenol organic matters from aqueous solutions.Na... A new magnetic nanocomposite chitosan/EDTA/CeZnO(MEC-CeZnO)is synthesized as an efficient and eco-friendly bio-compound for the removal of chromium Cr(VI)metal ions and phenol organic matters from aqueous solutions.Nanocomposites are characterized using field emission scanning electron microscope,energy dispersive X-ray spectroscopy,transmission electron microscope,X-ray diffraction,X-ray photoelectron spectroscopy,Fourier transform infrared spectroscopy,diffuse reflection spectroscopy,and PL methods.The reduction rate of Cr(VI)ions and phenol degradation is evaluated under various experimental conditions,separately and simultaneously.The average pore diameter and specific surface of MEC-CeZnO nanocomposite are obtained 50 nm and 210 m^(2)·g^(-1)respectively,which suggest the successful synthesis of the nanocomposite because of the increased surface area and reduced pores in comparison to previous studies.Moreover,the best Cr(VI)and phenol reduction efficiencies are 98%and 92%at 180 min of retention time,both following the Langmuir-Hinshelwood first-order kinetics.The mechanisms of Cr(VI)and phenol removal from aqueous solutions involved Cr(VI)reduction,phenol oxidation,and adsorption.Examining the reusability of MEC-CeZnO showed that both degradation and recovery capacity is stable in 5 cycles. 展开更多
关键词 Magnetic chitosan CHROMIUM PHENOL PHOTOCHEMISTRY Nanoparticles experimental validation
下载PDF
Prediction of Grinding Force by an Electroplated Grinding Wheel with Orderly-Micro-Grooves
14
作者 Cong Mao Jiali Wang +7 位作者 Mingjun Zhang Xincheng Wang Yuanqiang Luo Weidong Tang Kun Tang Zhuming Bi Yongle Hu Zhenheng Lin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期56-66,共11页
The ability to predict a grinding force is important to control,monitor,and optimize the grinding process.Few theoretical models were developed to predict grinding forces when a structured wheel was used in a grinding... The ability to predict a grinding force is important to control,monitor,and optimize the grinding process.Few theoretical models were developed to predict grinding forces when a structured wheel was used in a grinding process.This paper aimed to establish a single-grit cutting force model to predict the ploughing,friction and cutting forces in a grinding process.It took into the consideration of actual topography of the grinding wheel,and a theoretical grinding force model for grinding hardened AISI 52100 by the wheel with orderly-micro-grooves was proposed.The model was innovative in the sense that it represented the random thickness of undeformed chips by a probabilistic expression,and it reflected the microstructure characteristics of the structured wheel explicitly.Note that the microstructure depended on the randomness of the protruding heights and distribution density of the grits over the wheel.The proposed force prediction model was validated by surface grinding experiments,and the results showed(1)a good agreement of the predicted and measured forces and(2)a good agreement of the changes of the grinding forces along with the changes of grinding parameters in the prediction model and experiments.This research proposed a theoretical grinding force model of an electroplated grinding wheel with orderly-micro-grooves which is accurate,reliable and effective in predicting grinding forces. 展开更多
关键词 Electroplated grinding wheel Orderly-micro-grooves Grinding force Force prediction Undeformed chip thickness experimental validation
下载PDF
Numerical Modelling of Drying Induced Cracks in Wood Discs Using the Extended Finite Element Method
15
作者 Zongying Fu Yongdong Zhou +1 位作者 Tingguo Yan Yun Lu 《Journal of Renewable Materials》 SCIE EI 2023年第1期93-102,共10页
Drying crack is a common phenomenon occurring during moisture discharge from wood,reducing efficient wood utilization.Drying crack is primarily caused by drying stress,and the reasonable methods for determining drying... Drying crack is a common phenomenon occurring during moisture discharge from wood,reducing efficient wood utilization.Drying crack is primarily caused by drying stress,and the reasonable methods for determining drying stress are sparse.In this study,the initiation and propagation of cracks during wood discs drying were simulated using the extended finite element method(XFEM).The distribution of drying stress and displacement was analyzed at different crack conditions based on the simulation results.This study aimed to solve the problem of the limitation of drying stress testing methods and provide a new idea for the study of wood drying stress.The numerical simulation results are found in good agreement with the experimental results,thus corroborating the feasibility of XFEM in modeling drying crack of wood discs.The stress concentration was observed at the crack tip region,while a minor stress was presented in the region of crack passing through,indicating that the crack formation process was also a process of releasing drying stress.Further,more energy was required to form double cracks in comparison with the single crack mode. 展开更多
关键词 Wood drying queensland peppermint drying cracks numerical simulation experimental validation XFEM
下载PDF
Bioinformatics screening of breast cancer-related genes and potential drug research
16
作者 LIANG Xiao LI Ya-lan +2 位作者 BAI Hao-tian YANG Jing WANG Rui 《Journal of Hainan Medical University》 2023年第1期47-57,共11页
Objective:To search the the differentially expressed genes between breast cell carcinoma tissues and normal tissues by using bioinformatics technology,and the potential therapeutic drugs for breast cancer were identif... Objective:To search the the differentially expressed genes between breast cell carcinoma tissues and normal tissues by using bioinformatics technology,and the potential therapeutic drugs for breast cancer were identified,which can provide reference for clinical immune targeted therapy and drug therapy of breast cancer in the future.Methods:"Breast cancer"was searched by using Gene Expression Omnibus(GEO),and GSE79586 chip data was downloaded.The differentially expressed genes in the control group and the breast cancer model group were screened by using bio-communication technology and subjected to GO function analysis,KEGG pathway analysis,differential gene characteristic expression analysis and protein-protein interaction network(PPI)analysis,and the analysis results were further visualized.Prognosis analysis,related function prediction and immune infiltration analysis were performed using the GEPIA,GeneMANIA,and Timer2.0 databases,respectively.Finally,the compounds with potential therapeutic effects on breast cancer are identified through Connectivity Map(CMap).Western blotting and real-time PCR(RT-PCR)were used to verify the core genes and potential therapeutic agents with the highest correlation in vitro.Results:A total of 3916 differentially expressed genes including 1786 up-regulated genes and 2130 down-regulated genes were screened.GO analysis showed that the differential genes were mainly involved in the positive regulation of phosphorylation,secretory vesicles,racemase and epimerase activities.KEGG analysis showed that differential genes were involved in systemic lupus erythematosus,alcoholism,sticky spots,amoebic dysentery Ras signal pathways and other disease pathways.The characteristic expression analysis of differential genes showed that MEK inhibitors,HSP90 inhibitors and signal transduction pathway kinase inhibitors were drugs similar to the differential genes.PPI results showed that H2AFJ,TFF1,GATA3,FOXA1,and CDH1 were core genes related to breast cancer.Two core genes of H2AFJ and TFF1 with the highest correlation were further selected for GEPIA analysis.The results of the analysis showed that the mRNA expression levels of H2AFJ and TFF1 in breast cancer cells were significantly higher than those in normal tissues,and there was a significant correlation with the pathological staging,overall survival rate and disease-free survival rate of breast cancer patients.H2AFJ and TFF1 may be potential prognostic biomarkers for survival of breast cancer patients.The functions of differentially expressed H2AFJ and TFF1 are mainly related to hormone receptor binding,epithelial structure maintenance and epigenetic negative regulation of genes,chromatin tissue involved in negative regulation of transcription,etc.The results of immune infiltration showed that the expressions of H2AFJ and TFF1 had a significant correlation with the infiltration of macrophages,neutrophils,monocytes,CD4+T,CD8+T,B lymphocytes and other immune cells.CMap results showed that compounds such as Gefitinib,Alpelisib,Sorafenib,and Sunitinib had potential therapeutic effects on breast cancer.Western blot and RT-PCR results showed that H2AFJ and TFF1 were significantly overexpressed in breast cancer cells.Gefitinib significantly inhibited the expression of H2AFJ and TFF1 in breast cancer cells(P<0.05,P<0.01).Conclusion:In this study,differentially expressed genes between breast cell carcinoma tissues and normal tissues were screened out by bioinformatics means to further identify key genes and compounds with potential therapeutic effects in the onset process of breast cancer and to further verify the effectiveness of the screened drugs on breast cancer through experiments.It will provide reference for clinical research and development of new drugs against breast cancer in the future in order to develop more effective treatment options. 展开更多
关键词 Breast cancer Biological information technology Differentially expressed genes Potential drugs experimental validation
下载PDF
Numerical modeling of centrifuge cyclic lateral pile load experiments 被引量:8
17
作者 Nikos Gerolymos Sandra Escoffier +1 位作者 George Gazetas Jacques Garnier 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第1期61-76,共16页
To gain insight into the inelastic behavior of piles, the response of a vertical pile embedded in dry sand and subjected to cyclic lateral loading was studied experimentally in centrifuge tests conducted in Laboratoir... To gain insight into the inelastic behavior of piles, the response of a vertical pile embedded in dry sand and subjected to cyclic lateral loading was studied experimentally in centrifuge tests conducted in Laboratoire Central des Ponts et Chaussees. Three types of cyclic loading were applied, two asymmetric and one symmetric with respect to the unloaded pile. An approximately square-root variation of soil stiffness with depth was obtained from indirect in-flight density measurements, laboratory tests on reconstituted samples, and well-established empirical correlations. The tests were simulated using a cyclic nonlinear Winkler spring model, which describes the full range of inelastic phenomena, including separation and re-attachment of the pile from and to the soil. The model consists of three mathematical expressions capable of reproducing a wide variety of monotonic and cyclic experimentalp-y curves. The physical meaning of key model parameters is graphically explained and related to soil behavior. Comparisons with the centrifuge test results demonstrate the general validity of the model and its ability to capture several features of pile-soil interaction, including: soil plastification at an early stage of loading, "pinching" behavior due to the formation of a relaxation zone around the upper part of the pile, and stiffness and strength changes due to cyclic loading. A comparison of the p-y curves derived from the test results and the proposed model, as well as those from the classical curves of Reese et al. (1974) for sand, is also presented. 展开更多
关键词 centrifuge test Winkler model p-y curves cyclic loading pile-soil separation/gapping nonlinear response experimental validation
下载PDF
Mathematical Model and Experiment Validation of Fluid Torque by Shear Stress under Influence of Fluid Temperature in Hydro-viscous Clutch 被引量:6
18
作者 CUI Hongwei YAO Shouwen +2 位作者 YAN Qingdong FENG Shanshan LIU Qian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第1期32-40,共9页
The current design of hydro-viscous clutch(HVC) in tracked vehicle fan transmission mainly focuses on high-speed and high power. However, the fluid torque under the influence of fluid temperature can not be predicte... The current design of hydro-viscous clutch(HVC) in tracked vehicle fan transmission mainly focuses on high-speed and high power. However, the fluid torque under the influence of fluid temperature can not be predicted accurately by conventional mathematical model or experimental research. In order to validate the fluid torque of HVC by taking the viscosity-temperature characteristic of fluid into account, the test rig is designed. The outlet oil temperature is measured and fitted with different rotation speed, oil film thickness, oil flow rate, and inlet oil temperature. Meanwhile, the film torque can be obtained. Based on Navier-Stokes equations and the continuity equation, the mathematical model of fluid torque is proposed in cylindrical coordinate. Iterative method is employed to solve the equations. The radial and tangential speed distribution, radial pressure distribution and theoretical flow rate are determined and analyzed. The models of equivalent radius and fluid torque of friction pairs are introduced. The experimental and theoretical results indicate that tangential speed distribution is mainly determined by the relative rotating speed between the friction plate and the separator disc. However, the radial speed distribution and pressure distribution are dominated by pressure difference at the lower rotating speed. The oil film fills the clearance and the film torque increases with increasing rotating speed. However, when the speed reaches a certain value, the centrifugal force will play an important role on the fluid distribution. The pressure is negative at the outer radius when inlet flow rate is less than theoretical flow, so the film starts to shrink which decreases the film torque sharply. The theoretical fluid torque has good agreement with the experimental data. This research proposes a new fluid torque mathematical model which may predict the film torque under the influence of temperature more accurately. 展开更多
关键词 hydro-viscous clutch fluid torque by shear stress experiment validation mathematical model
下载PDF
Hover performance estimation and validation of battery powered vertical takeoff and landing aircraft 被引量:2
19
作者 王波 侯中喜 +1 位作者 鲁亚飞 朱雄峰 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第10期2595-2603,共9页
Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, mot... Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, motor and electronic speed controller, the power consumption model of propeller and the constant power discharge model of battery, an efficient method to estimate the hover endurance of battery powered VTOL aircraft was presented. In order to understand the mechanism of performance improvement, the impacts of propulsion system parameters on hover endurance were analyzed by simulations, including the motor power density, the battery capacity, specific energy and Peukert coefficient. Ground experiment platform was established and validation experiments were carried out, the results of which showed a well agreement with the simulations. The estimation method and the analysis results could be used for optimization design and hover performance evaluation of battery powered VTOL aircraft. 展开更多
关键词 vertical takeoff and landing hover endurance estimation battery powered aircraft experimental validation
下载PDF
Review on Tidal Energy Technologies and Research Subjects
20
作者 Chul Hee JO Su Jin HWANG 《China Ocean Engineering》 SCIE EI CSCD 2020年第1期137-150,共14页
Tidal current power is one of the promising and reliable renewable energies with the advantage of continuous and predictable resource. It can make stable electricity regardless of weather conditions or seasons all yea... Tidal current power is one of the promising and reliable renewable energies with the advantage of continuous and predictable resource. It can make stable electricity regardless of weather conditions or seasons all year around. The required technologies for tidal current power in the ocean have been developed for years and now recognized that it could be commercialized after intensive field tests and successful demonstrations. There are several tidal farm development projects in the world, such as the MeyGen project in UK with its commercialization at hand. However, various research subjects in the tidal current energy field are seeking improvements and industrialization of tidal current power in terms of economy and technical reliability. This paper introduces the resource assessment procedure of tidal energy that has been applied in Korea coastal regions. The key research subjects for tidal current power together with the interaction effect of multi-arrangement is described. Also, this paper is to introduce the research output of each subject such as turbine design, experimental validation, turbine interaction and wake, multi-array module, FSI (fluid-structure interaction), and duct application. 展开更多
关键词 tidal current power resource assessment turbine design experimental validation turbine interaction multi arrangement FSI(fluid-structure interaction)
下载PDF
上一页 1 2 3 下一页 到第
使用帮助 返回顶部