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基于WinForm窗体的光谱扫描系统设计
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作者 黄利强 《信息与电脑》 2024年第17期117-120,共4页
目前,国内市场上广泛使用的紫外–可见分光光度计、紫外–荧光分光光度计大部分不具备自动波长扫描功能,只能人工操作和读数,因此使用受到了极大的限制。本文设计了一款基于Visual C#WinForm窗体的光谱仪软件,通过串口接收紫外–可见分... 目前,国内市场上广泛使用的紫外–可见分光光度计、紫外–荧光分光光度计大部分不具备自动波长扫描功能,只能人工操作和读数,因此使用受到了极大的限制。本文设计了一款基于Visual C#WinForm窗体的光谱仪软件,通过串口接收紫外–可见分光光度计、紫外–荧光分光光度计等光谱仪器的检测数据,并在电脑端对数据进行处理后,可以自动计算出吸光度、透光率、荧光强度等光谱参数,直观地显示波长扫描光谱图。 展开更多
关键词 C# Win form Visual Studio 光谱扫描系统
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Analysis of the Properties and Anti-Seepage Mechanism of PBFC Slurry in Landfill
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作者 Guozhong Dai Jia Zhu +2 位作者 Guicai Shi Yanmin Sheng Shujin Li 《Structural Durability & Health Monitoring》 EI 2017年第2期169-190,共22页
As the landfill leachate has strong pollution on the underground water,surface water and soil.This paper develops the formula of impervious slurry with low permeability,good durability,strong adsorption and retardant ... As the landfill leachate has strong pollution on the underground water,surface water and soil.This paper develops the formula of impervious slurry with low permeability,good durability,strong adsorption and retardant based on the bentonite which is modified by polyvinyl alcohol.Through the simulation experiment,the optimum formula of polyvinyl alcohol is 0.2%.Its osmotic coefficient for 28 days is 0.53×10^-8~1.86×10^-8 cm/s and compressive strength is 0.5~1.5 MPa as well.This paper study on the retardant rule of the consolidation of slurry against the pollution in the leachate by self-made percolation instrument.The experiment shows that the retardant rate of the consolidation against inorganic pollutants and organic pollutants is over 85% and the retardant rate against heavy metal ion such as Hg and Pb is above 99%.The slurry has the characteristics of low permeability,high retardant against pollution,good durability and plasticity,no chemical additives,no pollution,wide source of raw materials and good economy which determine it can be used to new landfill or existing landfill,building foundation pit and water conservancy project. 展开更多
关键词 Waste landfill anti-seepage slurry seepage resistance adsorption property corrosion resistance durability mechanical property
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Discussion on Anti-seepage Wall and Anti-seepage Technology of Water Conservancy Project
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作者 Jie Tao Qingpo Wang 《Journal of World Architecture》 2020年第5期14-17,共4页
The water infiltration problem of water conservancy projects is one of the more common problems in the construction of water conservancy projects,which seriously affects the overall construction quality and safety of ... The water infiltration problem of water conservancy projects is one of the more common problems in the construction of water conservancy projects,which seriously affects the overall construction quality and safety of water conservancy projects.This article studies the causes of water infiltration in water conservancy projects and introduces related antiseepage technologies,hoping to be a reference for the implementation of anti-seepage projects.Through research,it is found that the factors that cause water infiltration in water conservancy projects include water conservancy project structural changes,environmental factors and construction factors.Relevant personnel can use concrete anti-seepage wall construction technology and high-pressure jet grouting technology to do the relevant anti-seepage work of water conservancy projects. 展开更多
关键词 Water conservancy project anti-seepage technology anti-seepage wall
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Application of Anti-seepage Technology in the Construction of Hydraulic Engineering Projects
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作者 Huanlin YANG 《Meteorological and Environmental Research》 CAS 2023年第5期31-32,35,共3页
With the development of China's economy,the implementation scale and scope of hydraulic engineering projects are increasing,and the application of anti-seepage technology has an important influence on the construc... With the development of China's economy,the implementation scale and scope of hydraulic engineering projects are increasing,and the application of anti-seepage technology has an important influence on the construction quality of hydraulic engineering.In this paper,the significance and problems of the application of anti-seepage technology in the construction of hydraulic engineering projects were mainly analyzed,and specific application strategies were proposed. 展开更多
关键词 anti-seepage technology Hydraulic engineering projects Application strategy
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Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence 被引量:1
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作者 Jiazhen ZHAO Shengping HE +2 位作者 Ke FAN Huijun WANG Fei LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1465-1482,共18页
Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Ar... Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. Here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions scenario.Thereafter, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained). 展开更多
关键词 wintertime newly formed Arctic sea ice model democracy model weighting scheme model performance model independence
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Microstructure and forming mechanism of metals subjected to ultrasonic vibration plastic forming: A mini review
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作者 Qinghe Cui Xuefeng Liu +4 位作者 Wenjing Wang Shaojie Tian Vasili Rubanik Vasili Rubanik Jr. Dzmitry Bahrets 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1322-1332,共11页
Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the workpiece.This technology has a very broad appli... Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the workpiece.This technology has a very broad application prospect in industrial manufactur-ing.Researchers have conducted extensive research on the ultrasonic vibration plastic forming of metals and laid a deep foundation for the development of this field.In this review,metals were classified according to their crystal structures.The effects of ultrasonic vibration on the microstructure of face-centered cubic,body-centered cubic,and hexagonal close-packed metals during plastic forming and the mech-anism underlying ultrasonic vibration forming were reviewed.The main challenges and future research direction of the ultrasonic vibra-tion plastic forming of metals were also discussed. 展开更多
关键词 ultrasonic vibration plastic forming crystal structure MICROSTRUCTURE forming mechanism
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Discussion on Anti-Seepage Technologies in the Construction of Small-Scale Rural Water Conservancy Projects
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作者 Suxiang Yuan 《Journal of World Architecture》 2022年第2期19-24,共6页
In order to ensure the sustainable growth of rural economy,it is necessary to carry out further research on small-scale water conservancy projects and solve the seepage issue in rural areas.Based on the application si... In order to ensure the sustainable growth of rural economy,it is necessary to carry out further research on small-scale water conservancy projects and solve the seepage issue in rural areas.Based on the application significance of small-scale rural water conservancy projects and the analysis of anti-seepage technologies,along with specific examples,this paper specifically discusses the application of high-pressure jet technology,so as to provide reference for the development of engineering construction. 展开更多
关键词 Small-scale water conservancy projects Rural areas anti-seepage technology High-pressure jet
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ELLIPTIC EQUATIONS IN DIVERGENCE FORM WITH DISCONTINUOUS COEFFICIENTS IN DOMAINS WITH CORNERS
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作者 Jun CHEN Xuemei DENG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1903-1915,共13页
We study equations in divergence form with piecewise Cαcoefficients.The domains contain corners and the discontinuity surfaces are attached to the edges of the corners.We obtain piecewise C^(1,α) estimates across th... We study equations in divergence form with piecewise Cαcoefficients.The domains contain corners and the discontinuity surfaces are attached to the edges of the corners.We obtain piecewise C^(1,α) estimates across the discontinuity surfaces and provide an example to illustrate the issue regarding the regularity at the corners. 展开更多
关键词 elliptic equations divergence form discontinuous coefficients corner regularity
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Representation of an Integer by a Quadratic Form through the Cornacchia Algorithm
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作者 Moumouni Djassibo Woba 《Applied Mathematics》 2024年第9期614-629,共16页
Cornachia’s algorithm can be adapted to the case of the equation x2+dy2=nand even to the case of ax2+bxy+cy2=n. For the sake of completeness, we have given modalities without proofs (the proof in the case of the equa... Cornachia’s algorithm can be adapted to the case of the equation x2+dy2=nand even to the case of ax2+bxy+cy2=n. For the sake of completeness, we have given modalities without proofs (the proof in the case of the equation x2+y2=n). Starting from a quadratic form with two variables f(x,y)=ax2+bxy+cy2and n an integer. We have shown that a primitive positive solution (u,v)of the equation f(x,y)=nis admissible if it is obtained in the following way: we take α modulo n such that f(α,1)≡0modn, u is the first of the remainders of Euclid’s algorithm associated with n and α that is less than 4cn/| D |) (possibly α itself) and the equation f(x,y)=n. has an integer solution u in y. At the end of our work, it also appears that the Cornacchia algorithm is good for the form n=ax2+bxy+cy2if all the primitive positive integer solutions of the equation f(x,y)=nare admissible, i.e. computable by the algorithmic process. 展开更多
关键词 Quadratic form Cornacchia Algorithm Associated Polynomials Euclid’s Algorithm Prime Number
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Assessment of the Drafting Quality of Request Forms Submitted to the Malaria and Parasitology Units at the Institut Pasteur de Cote d’Ivoire
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作者 Yao Serge-Stéphane Ako Ako Bérenger Aristide +4 位作者 Sylvain Beourou Ouattara Yacouba N’Guessan Tiacoh Landry N’Dri Kouadio Thierry-Borel Toure André Offianan 《Journal of Biosciences and Medicines》 2024年第5期330-339,共10页
Biological tests provide information on the medical analysis requested by both the patient and the prescriber. It is a communication link between the prescriber and the laboratory staff. The lack of some information o... Biological tests provide information on the medical analysis requested by both the patient and the prescriber. It is a communication link between the prescriber and the laboratory staff. The lack of some information on request forms not only affects the drafting quality of the test and patient care, but could also make thousands of data produced by healthcare centers unusable. The aim of this study was to assess the drafting quality of request forms submitted to the Malaria and Parasitology Units at the Institut Pasteur de Côte d’Ivoire. Methods: It was a descriptive cross-sectional study to assess the drafting quality of request forms of various prescribers received at the Institut Pasteur de Côte d’Ivoire. This study was conducted at the Malaria and Parasitology Units, department of Parasitology and Mycology (Institut Pasteur de Côte d’Ivoire), from 6<sup>th</sup> December 2020 to 6<sup>th</sup> December 2021. The information on each request forms was recorded on a data collection form designed for this purpose. Each data collection form corresponds to a request forms and each test to a patient. Results: Out of a total of 1990 request forms received, the patient’s age and sex were missing on 18% and 26.8% of the tests respectively. More than half (51.80%) of request forms did not indicate the patient’s place of residence. Clinical information was not provided on 45.90% of the tests. Prescribers omitting their signatures were 51%, stamps were 50.3% and contacts were 71.2%. Only 5.4% of request forms were of good drafting quality. Providing all the required information on the forms could facilitate the use and analysis of data and samples. 展开更多
关键词 Laboratory QUALITY Request forms Information
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Study on Effectiveness of Solitary-Wave-Like Form Based on Overtopping Data from Irregular Wave Tests
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作者 LI Xiao-liang Huang Gui-biao 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期701-710,共10页
The previous study conducted by Li(2022)demonstrates that the Goda graph can be adequately represented by a solitary-wave-like form across the entire range of relative water depth,with the exception of the extremely s... The previous study conducted by Li(2022)demonstrates that the Goda graph can be adequately represented by a solitary-wave-like form across the entire range of relative water depth,with the exception of the extremely shallow zone.However,it remains uncertain whether this form is equally effective when applied to test data generated by irregular waves,as the Goda graph was initially developed based on overtopping data from regular wave tests.Additionally,it is unclear whether this form is suitable for formulating overtopping discharge at composite vertical walls.In order to address these questions,a 2D overtopping experiment was conducted,incorporating both simple and composite types of vertical walls,with various relative water depths across the entire range,excluding the extremely shallow zone.A novel analysis procedure was developed,which proved to be highly productive and can be considered a general method for data fitting.Ultimately,the study yielded two conclusions:(1)the solitary-wave-like form is remarkably effective in formulating overtopping test data generated by irregular waves,regardless of whether the vertical wall is simple or composite,and(2)the resulting formulas exhibit definitely better performance compared with existing formulas. 展开更多
关键词 solitary-wave-like form overtopping discharge overtopping formula vertical wall
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Bioaccumulation,subcellular distribution and chemical forms of cadmium in Aster subulatus Michx.
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作者 LIANG Xue-lian CHEN Wei +7 位作者 JIANG Wen-yan LIAO Jie YANG Yu-xia WANG Hai-jun LI Hui-ling LU Wei-fan WANG Tian-shun XIE Hong-zhao 《南方农业学报》 CAS CSCD 北大核心 2024年第8期2386-2395,共10页
【Objective】Through analyzing the bioaccumulation capacity,subcellular distribution and chemical forms of cadmium(Cd)in Aster subulatus Michx.,this study was to provide reference for revealing the Cd tolerance mechan... 【Objective】Through analyzing the bioaccumulation capacity,subcellular distribution and chemical forms of cadmium(Cd)in Aster subulatus Michx.,this study was to provide reference for revealing the Cd tolerance mechanism of A.subulatus Michx.【Method】After cultured for 24 d under the action of Hoagland nutrient solution and gradient Cd concentrations(0,30,60 and 90 mg/L),A.subulatus Michx.were harvested,and its leaf,stem and root were treated by differential centrifugation,chemical reagent extraction,and digested with graphite digester,respectively,then the Cd content in the root,stem and leaf were determined by atomic absorption spectroscopy.【Result】The experimental results indicated that the bioaccumulation capacity of Cd in A.subulatus Michx.was root>stem>leaf,and the maximum Cd concentration in the root,stem and leaf of A.subulatus Michx.were 130.74,78.69 and 56.62 mg/kg(fresh matter),respectively.Most of Cd stored in the cell wall and the soluble fractions of the root and leaf of A.subulatus Michx.,with only a smaller portion Cd in organelle fraction.Analysis result of subcellular Cd content showed that 52.27%-58.61%of Cd for root was mainly stored in the soluble fraction,but 42.10%-63.28%of Cd for leaf was mainly stored in the cell wall fraction.The concentration of pectates and protein integrated-Cd was higher in the root and leaf compared to other chemical forms Cd.Pectates and protein integrated-Cd was the main chemical forms Cd in the root and leaf of A.subulatus Michx.,and their percentages were 68.91%-74.80%and 57.38%-83.80%,respectively.Cd treatment could significantly increase the proportion of water-soluble organic acid Cd from 13.64%to 22.72%in root and undissolved phosphate Cd from 10.02%to 32.78%in leaf with increasing Cd concentration in the culture medium.【Conclusion】The root,stem and leaf of A.subulatus Michx.has strong bioaccumulation capacity to Cd,Cd is primarily stored in the soluble fractions of the root and cell wall fractions of the leaf,and less toxic pectates and protein integrated-Cd is the main chemical forms Cd in the root and leaf of A.subulatus Michx.,this might be the main mechanism of Cd tolerance in A.subulatus Michx. 展开更多
关键词 Aster subulatus Michx. CADMIUM BIOACCUMULATION chemical form subcellular distribution
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Familial Forms of Spondyloarthritis Study of 100 Senegalese Multiplex Families
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作者 Adama Bah Chiekh Ahamadou Bamba Diaw +10 位作者 Dieynaba Sala Tamara Kane Adama Doucouré Siddiki Charifah Ramadhane Bouchrane Harine Abdel Aziz Garba Aissatou N’diaye Mondukpe Joane Immanuelle Houansou Laurine Marlyse Adogle Yaye Aminata Gueye Moustapha Niasse Saidou Diallo 《Open Journal of Rheumatology and Autoimmune Diseases》 2024年第3期132-143,共12页
Introduction: Spondyloarthritis (SpA) comprises a group of chronic inflammatory rheumatic diseases characterized by predominant axial involvement. These include ankylosing spondylitis (AS), reactive arthritis (ReA), p... Introduction: Spondyloarthritis (SpA) comprises a group of chronic inflammatory rheumatic diseases characterized by predominant axial involvement. These include ankylosing spondylitis (AS), reactive arthritis (ReA), psoriatic arthritis (PsA), arthritis associated with inflammatory bowel diseases (IBD), SAPHO syndrome (Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis), juvenile spondyloarthritis (JSPA), and undifferentiated SpA. Their exact cause is unknown but is believed to stem from a combination of factors. The first familial forms were described by de Blécourt et al. in 1961. The objective was to evaluate the epidemiological, clinical, therapeutic and evolutionary aspects of familial forms of SpA and in particular, to prove the severity of the disease in family members compared to index cases in the rheumatology department of the Aristide Le Dantec University Hospital in Dakar. Methodology: This was a prospective, cross-sectional and descriptive study with an analytical aim on patients with the familial form of spondyloarthritis defined by the existence of at least one other family member with SpA outside the propositus, collected within the Aristide Le Dantec rheumatology department in Dakar over a period of 10 years between January 2012 and December 2021. There were two phases of study, the first of which consisted of collecting index cases with miserly SpA and the second of which consisted of family screening after consent. The data analysed were epidemiological, clinical, paraclinical, therapeutic and evolving. Results: Out of 100 families of 1905 members, 667 SpA patients included, i.e. a prevalence of 35%, including 225 (33.73%) men and 412 women (61.17%), i.e. a ratio of 1.8. The mean age at diagnosis among relatives was 26.3 years (range 13 and 80 years), 47.14 years among the propositus, in whom the mean age at onset was 36.26 years and that of relatives 49.9 years in the first degree, 15 years in the second degree and 1 year in the third degree. The time to diagnosis was 11.20 years in the first degree, 2.5 years in the second degree, 1 year in the third degree and 10.88 years in the case of the proposes. The number of marriages in families was 420 of which 116 were consanguineous (consanguinity rate 27.62%), 19% among the propositus. HLA-B27 positive in 92% of the proposers and 33.43% in the families;70% of the propositus had an inflammatory syndrome and 17.54% in the families;87% of sacroilliitis in the propositus and 5.54% in the families. Clinical forms were dominated by undifferentiated SpA (338 cases) and APS (295 cases). The average BASFI was 3.23 on D0;2.59 in the 3rd month and 1 in the 6th month for the propositus versus 2.55 at D0;1.86 at the 3rd month and 1.55 in the 6th month in the families. Average BASDAI was 3.92 at D0;3.12 at the 3rd month and 2.07 at the 6th month in the propositus and 3 at D0;2.21 at the 3rd month and 1 at the 6th month in the families. Autoimmune associated conditions were 18 cases, degenerative 24 cases, autoinflammatory 2 metabolic cases 18 cases. They all received: NSAIDs, methotrexate, salazopyrine (11 cases) and anti-TNF-α (1 case). The evolution was generally favourable. Conclusion: SpA is on the rise in Senegalese hospitals, frequent in young people, SPA and undifferentiated SpA are the most frequent, management is essentially based on conventional care, and the disease is less severe in family members than index cases. 展开更多
关键词 Familial forms of Spondyloarthritis Propositus Senegal
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MPI/OpenMP-Based Parallel Solver for Imprint Forming Simulation
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作者 Yang Li Jiangping Xu +2 位作者 Yun Liu Wen Zhong Fei Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期461-483,共23页
In this research,we present the pure open multi-processing(OpenMP),pure message passing interface(MPI),and hybrid MPI/OpenMP parallel solvers within the dynamic explicit central difference algorithm for the coining pr... In this research,we present the pure open multi-processing(OpenMP),pure message passing interface(MPI),and hybrid MPI/OpenMP parallel solvers within the dynamic explicit central difference algorithm for the coining process to address the challenge of capturing fine relief features of approximately 50 microns.Achieving such precision demands the utilization of at least 7 million tetrahedron elements,surpassing the capabilities of traditional serial programs previously developed.To mitigate data races when calculating internal forces,intermediate arrays are introduced within the OpenMP directive.This helps ensure proper synchronization and avoid conflicts during parallel execution.Additionally,in the MPI implementation,the coins are partitioned into the desired number of regions.This division allows for efficient distribution of computational tasks across multiple processes.Numerical simulation examples are conducted to compare the three solvers with serial programs,evaluating correctness,acceleration ratio,and parallel efficiency.The results reveal a relative error of approximately 0.3%in forming force among the parallel and serial solvers,while the predicted insufficient material zones align with experimental observations.Additionally,speedup ratio and parallel efficiency are assessed for the coining process simulation.The pureMPI parallel solver achieves a maximum acceleration of 9.5 on a single computer(utilizing 12 cores)and the hybrid solver exhibits a speedup ratio of 136 in a cluster(using 6 compute nodes and 12 cores per compute node),showing the strong scalability of the hybrid MPI/OpenMP programming model.This approach effectively meets the simulation requirements for commemorative coins with intricate relief patterns. 展开更多
关键词 Hybrid MPI/OpenMP parallel computing MPI OPENMP imprint forming
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Schur Forms and Normal-Nilpotent Decompositions
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作者 LI Zhen 《应用数学和力学》 CSCD 北大核心 2024年第9期1200-1211,共12页
Real and complex Schur forms have been receiving increasing attention from the fluid mechanics community recently,especially related to vortices and turbulence.Several decompositions of the velocity gradient tensor,su... Real and complex Schur forms have been receiving increasing attention from the fluid mechanics community recently,especially related to vortices and turbulence.Several decompositions of the velocity gradient tensor,such as the triple decomposition of motion(TDM)and normal-nilpotent decomposition(NND),have been proposed to analyze the local motions of fluid elements.However,due to the existence of different types and non-uniqueness of Schur forms,as well as various possible definitions of NNDs,confusion has spread widely and is harming the research.This work aims to clean up this confusion.To this end,the complex and real Schur forms are derived constructively from the very basics,with special consideration for their non-uniqueness.Conditions of uniqueness are proposed.After a general discussion of normality and nilpotency,a complex NND and several real NNDs as well as normal-nonnormal decompositions are constructed,with a brief comparison of complex and real decompositions.Based on that,several confusing points are clarified,such as the distinction between NND and TDM,and the intrinsic gap between complex and real NNDs.Besides,the author proposes to extend the real block Schur form and its corresponding NNDs for the complex eigenvalue case to the real eigenvalue case.But their justification is left to further investigations. 展开更多
关键词 Schur form normal matrix nilpotent matrix tensor decomposition vortex identification
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Deformation mechanisms and microstructural characteristics of AZ61 magnesium alloys processed by a continuous expansion extrusion approach
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作者 Yang Mo Fulin Jiang +4 位作者 Hang Xu Jie Tang Dingfa Fu Hui Zhang Jie Teng 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第7期2826-2846,共21页
The unique continuous extrusion-based severe plastic deformation approaches were proposed recently to process high-performance magnesium (Mg) alloys,while the in-depth deformation mechanisms under such complicated the... The unique continuous extrusion-based severe plastic deformation approaches were proposed recently to process high-performance magnesium (Mg) alloys,while the in-depth deformation mechanisms under such complicated thermomechanical conditions were not well understood In the present work,the fundamental deformation behaviors of AZ61 Mg alloy from 25 to 400°C were firstly examined under uniaxial compression deformation.Then the deformation mechanisms and microstructural characteristics of AZ61 Mg alloy during continuous expansion extrusion forming (CEEF) were systematically investigated by microstructural observations,finite element and cellular automata simulations The results showed that the continuous evolutions of temperature,larger strain level and complex stress state with strain rate range of 0~5.98 s-1during CEEF brought the distinctive dynamic recrystallization behaviors and texture development in AZ61 Mg alloy,which were different to that of uniaxial compression deformation.In details,a remarkable grain refinement was achieved via CEEF processing due to the simultaneous actions of continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX).Gradually enhanced CDRX were observed from center to edge region,which had significant effects on the texture distribution and texture strength.The c-axis of most grains rotated under distinctive shear strain following parabolic metal flow,resulting in stable fiber texture.In addition,the evolution of the internal texture of the alloy led to an obvious increase in the Schmid factor for the activation of basal(c+a)slip system.©2022 Chongqing University.Publishing services provided by Elsevier B.V.on behalf of Ke Ai Communications Co.Ltd. 展开更多
关键词 Magnesium alloy Deformation Continuous expansion extrusion forming Microstructure Finite element simulation
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Comparison between Two Different Manufactured Forms of β-Tricalcium Phosphate Bone Graft in Immediate Implant Placement
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作者 Abdulaleem Mahmoud Sharroud Abdel Aziz Baiomy Abdullah Mohamed Alaa El-Din Mohamed 《Open Journal of Stomatology》 2024年第11期410-420,共11页
Objectives: The aim of this study was to compare the efficacy of using the synthetic β-TCP bone grafting material in two different manufacturing forms (putty and granular) in grafting the jumping zone around immediat... Objectives: The aim of this study was to compare the efficacy of using the synthetic β-TCP bone grafting material in two different manufacturing forms (putty and granular) in grafting the jumping zone around immediate implant. Patients and Method: A randomized controlled clinical and radiographic trial was conducted on 24 male patients aged from 45 - 55 with badly decayed non-restorable teeth in the posterior mandibular area and seeking for receiving immediate dental implant directly after extraction. Vertical bone height and bone density were taken at time of implant placement and 6 months postoperatively. Results: The Putty form group and the Granular form group did not differ statistically in terms of age, post-operative complications, or implant outcome six months postoperatively. Additionally, there was a statistically significant increase in Putty form group compared to the Granular form group regarding Marginal bone loss 6 months postoperatively, but there was no statistically significant difference between the Putty form group and the Granular form group regarding Bone density by CBCT. Conclusion: The β-TCP Putty material, compared to β-TCP granular, displayed better surgical handling properties, and both forms had no adverse effect on bone formation, bone tissue maturation or graft volume stability, The β-TCP granular material, compared to β-TCP putty, displayed less marginal bone loss 6 months post-operatively. 展开更多
关键词 β-Tricalcium Phosphate Bone Substitute Putty form and Granular form Grafting the Jumping Zone around Immediate Implant
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Evaluation of Laboratory Request Forms Completion in a Tertiary Medical Laboratory of the Democratic Republic of Congo
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作者 Mamy Ngole Dahlia Pambu +3 位作者 Nathan Luana Dophie Tshibuela Ritha Nyembu Kibambe Bizette Bizeti Nsangu 《Journal of Biosciences and Medicines》 2024年第6期94-100,共7页
Background: The inadequacy in the completeness of the Laboratory Request Form (LRF) has been reported as one of the major sources of errors during the pre-analytical step of laboratory analysis. To prevent the occurre... Background: The inadequacy in the completeness of the Laboratory Request Form (LRF) has been reported as one of the major sources of errors during the pre-analytical step of laboratory analysis. To prevent the occurrence of such errors, this study aimed at assessing the level of completeness of LRFs. Methods: A retrospective analysis of laboratory request forms was conducted at the Clinical Biology Laboratory of the Kinshasa University Clinic, DR Congo, between November 2021 to May 2022. The LRFs were evaluated according to the completeness of all sections including administrative data of the patient, data of physician who ordered the test, relevant patient’s clinical data and data of the biological sample. Results: From a total of 2842 LRFs evaluated, none was fully completed with all required information. Particularly, patient’s clinical data including the medical history, provisional diagnosis and current treatment, were the most absent in 99% LRFs. However, two sections related to patient’s ID and prescribed test were informed in 100% LRFs. Conclusion: The results of this preanalytical audit can serve as an improvement opportunity focused on strengthening awareness about complete filling of LRF. 展开更多
关键词 AUDIT Laboratory Requisition form Clinical Biology Laboratory COMPLETENESS
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Modeling monocular form deprivation in rabbits using a simulated-cataract intraocular lens
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作者 Si-Yi Gu Li-Ming Xu +9 位作者 Wei-Jie Sun Li-Li Liang Lei Lin Han Zou Jing-Yuan Xu Yu Zheng Yuan-Yuan Li Yin-Ying Zhao Ping-Jun Chang Yun-E Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第12期2177-2184,共8页
AIM:To establish an animal model of form deprivation amblyopia based on a simulated cataract intraocular lens(IOLs).METHODS:Poly(dimethyl siloxane)-SiO_(2) thin films(PSF)with different degrees of opacity as IOL mater... AIM:To establish an animal model of form deprivation amblyopia based on a simulated cataract intraocular lens(IOLs).METHODS:Poly(dimethyl siloxane)-SiO_(2) thin films(PSF)with different degrees of opacity as IOL materials were prepared.The light transmission of the PSF-IOL was measured,and its in vitro biosafety was determined by cell counting kit(CCK)-8 assay using the HLEC-B3 cell line and ARPE-19 cell line.Subsequently,the in vivo safety was determined by implanting the PSF-IOL with 10%wt SiO_(2) into the right eyes of New Zealand white rabbits(PSF-IOL group),and compared with two control groups:contralateral comparison group and normal control(NC)group(Contralateral comparison group:the fellow eye;NC group:a group of binocular normal rabbits without intervention).The flash visual-evoked potentials(F-VEPs)were measured to verify amblyopia.RESULTS:PSFs containing 0,2%,and 10%wt SiO_(2) were successfully constructed.The 0 SiO_(2) PSF was transparent,while the 10%wt SiO_(2) PSF was completely opaque.It was found that PSF did not induce unwanted cytotoxicity in HLECs and ARPE19 cells in vitro.In vitro,PSF-IOL with 10%wt SiO_(2) was also non-toxic,and no significant inflammation or structural changes occurred after four weeks of PSF-IOL implantation.Finally,our IOL-simulated congenital cataract rabbit detected by F-VEPs suggested tentative amblyopia.CONCLUSION:A PSF-IOL that mimics cataracts is created.A novel form deprivation model is created by the IOL-simulated congenital cataract rabbit.It can be developed fast and stable and holds great potential for future study. 展开更多
关键词 monocular deprivation form deprivation intraocular lens congenital cataract AMBLYOPIA
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Approach Based on Response-Surface Method to Optimize Lining of Dies Used in 3D Free-Bending Forming Technology
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作者 Cheng Cheng Jiaxin Guo +2 位作者 Ali Abd El‑Aty Jie Tao Xunzhong Guo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第5期307-331,共25页
In three-dimensional free-bending forming(3D-FBF),the tube is not overly constrained,and the plastic deformation behavior and forming quality of the bent tube are significantly affected by the critical structure of th... In three-dimensional free-bending forming(3D-FBF),the tube is not overly constrained,and the plastic deformation behavior and forming quality of the bent tube are significantly affected by the critical structure of the forming die lining.However,the effects of die-lining structural parameters on the tube quality,and a method to determine the combination of die-lining structural parameters is yet to be devised.This study aims to propose a new framework that allows one to understand the effects of various die-lining structural parameters on tube quality and to propose the best combination of die-lining structural parameters.First,finite-element modeling is performed to simulate 3D-FBF and examine the effects of individual die-lining structures on the quality of tube formation.The simulation results show that the deformation-zone length and die gap are positively correlated with the tube-section distortion and wall-thickness variation,whereas it shows an opposite trend with respect to the bending radius.Additionally,the lining chamfer radius of the bending die and the guide lining chamfer radius minimally affect the tube forming quality.Subsequently,the optimal die-lining structure is obtained using the response-surface method.The tube cross-sectional distortion rate reduced from 2.73 to 2.53%after the die lining is optimized.Additionally,the average inner-wall thickness reduced to 1.06 mm,whereas the average outer-wall thickness increased to 0.97 mm.This paper proposes a method for optimizing the forming-die-lining mechanism and for improving the tube forming quality in 3D-FBF. 展开更多
关键词 Die lining forming quality Response surface method Cross-sectional distortion Wall thickness
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