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Surface nanostructure formation mechanism of 45 steel induced by supersonic fine particles pombarding

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Journal of University of Science and Technology Beijing 2008年第5期15卷 561-567页

作者： Dema ba Shining ma Changqing Li Fanjun Meng Department of Remanufacture Engineering Academy of Armored Force Engineering Beijing 100072 China

By means of supersonic fine particles bombarding （SFPB）,a nanostructured surface layer up to 15 μm was fabricated on a 45 steel plate with ferrite and pearlite phases. To reveal the grain refinement mechanism of SFPB-treated 45 steel,microstructure features of various sections in the treated surface were systematically characterized by X-ray diffraction （XRD）,scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. Grain size increases with an increase of depth from the treated surface. Plastic deformation and grain refinement processes are accompanied by an increase in strain. Plastic deformation in the proeutectoid ferrite phases has precedence over the pearlite phases. Grain refinement in the ferrite phases involves： the onset of dislocation lines （Dls）,dislocation tangles （DTs） and dense dislocation walls （DDWs） in the original grains; the formation of fine lamellar and roughly equiaxed cells separated by DDWs; by dislocation annihilation and rearrangement,the transformation of DDWS into subboundaries and boundaries and the formation of submicron grains or subgrains; the successive subdivision of grains to finer and finer scale,resulting in the formation of highly misoriented nano-grains. By contrast,eutectoid cementite phase accommodated strain in a sequence as follows： onset of elongated,bended and shear deformation under deformation stress of ferrites,short and thin cementites with a width of about 20-50 nm and discontinuous length were formed. Shorter and thinner cementites were developed into ultra-fine pieces under the action of high density dislocation and strains. At the top surface,some cementites were decomposed under severe plastic deformation. Experimental evidences and analysis indicate that surface nanocrystallization of 45 steel results from dislocation activities,high strains and high strain rate are necessary for the formation of nanocrystallites.

关键词： surface nanocrystallization grain refinement mechanism microstructure 45 steel

Evaluation of physicochemical and functional properties of protein isolates from 5 edible mushroom species

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Food Science and human Wellness 2024年

作者： Zheng Qian Mengdie Yang Xiao Chen Qiping Zhan Lei Zhong Qiuhui hu Liyan Zhao Key Laboratory of Edible Mushroom Processing， Ministry of Agriculture and Rural Affairs， College of Food Science and Technology， Nanjing Agricultural University College of Food Science and Engineering， Nanjing University of Finance and Economics

Edible mushroom proteins are the promising ones with the advantages of complete essential amino acid profile and multiple functional activities. To reinforce their applications in functional food development， this study comprehensively evaluated the physicochemical and functional properties of protein isolates from 5 mushroom species， i.e.， Pleurotus eryngii (PEP)， Pleurotus ostreatus (POP)， Lentinula edodes (LEP)， Flammulina velutipes (FVP) and Hypsizygus marmoreus (HMP). Results showed that PEP， LEP， FVP， POP and HMP exhibited better protein solubility (PS)， water holding capacity (WHC)， emulsifying capacity (EAI)， and foaming capacity (FC) than those of soybean protein and pea protein isolates. PEP (51.95%) and POP (49.15%) had a higher amount of β-sheet structure. Principal component analysis and correlation analysis showed that the seven proteins could be divided into 3 clusters， and WHC， EAI and FC were significantly positively correlated with PS and β-sheet. The least gelation concentration of PEP (16%) and FVP (16%) at pH 6.0 and 7.0 was similar to PPI， and PEP showed better hardness， springiness and rheological properties than other proteins gels. Overall， our study showed that 5 edible mushroom proteins possessed excellent functionalities (except for gelling capacity)， which provided novel insights on unexploited sources of mushroom proteins used as protein-based foods in the food industry.

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基于ba-SVM的冬小麦旱情表型分析与诊断

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农业工程学报 2024年第10期40卷 128-135页

作者：潘肖宇李子明吴文勇胡雅琪马蒙郭爱科石河子大学水利建筑工程学院石河子832000 中国水利水电科学研究院北京100084

提升作物水分表型诊断精度和时效性是当前智慧灌溉领域研究的难点和热点之一。该研究针对以上难点提出了一种改进机器视觉算法的冬小麦旱情智能诊断方法。在测坑试验系统中设置了适宜水分处理(CK)、中度干旱处理(T1)、重度干旱处理(T2)... 详细信息

提升作物水分表型诊断精度和时效性是当前智慧灌溉领域研究的难点和热点之一。该研究针对以上难点提出了一种改进机器视觉算法的冬小麦旱情智能诊断方法。在测坑试验系统中设置了适宜水分处理(CK)、中度干旱处理(T1)、重度干旱处理(T2),通过数码相机获取冬小麦早期RGB高清图像,利用HSV色彩空间改进的K-means聚类算法对小麦图像分割敏感区域,提取图像颜色和纹理特征数据并开展主成分分析,辨别出累计贡献率达到97.2%的前3维主成分。采用蝙蝠算法优化支持向量机(bat algorithm-support vector machine,ba-SVM)惩罚因子(c=5)和核参数(σ=0.1),建立了基于蝙蝠算法优化的冬小麦旱情感知支持向量机模型,运用主成分分析降维后的识别精度优于其他特征组合,识别正确率为96.5%。明显高于GA-SVM(6.5%)和SVM(9.3%),运行时间分别缩短7、14 s。构建了冬小麦旱情智能诊断方法,可为实时诊断冬小麦旱情和智慧灌溉决策提供参考。

关键词：机器视觉干旱胁迫主成分分析支持向量机蝙蝠算法冬小麦

UHPC增强短搭接RC构件承载力可靠度分析与加固建议

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防灾减灾工程学报 2024年第3期44卷 605-615页

作者：马高马忍湖南大学土木工程学院湖南长沙410082 工程结构损伤诊断湖南省重点实验室(湖南大学) 湖南长沙410082

基于可靠度研究超高性能混凝土(Ultra‐High Performance Concrete,UHPC)增强钢筋短搭接RC构件的失效模式与承载力特征。首先阐述了UHPC加固机理,建立了包含活恒荷载效应比、搭接系数m、UHPC强度、混凝土强度、钢筋型号、考虑水平地震... 详细信息

基于可靠度研究超高性能混凝土(Ultra‐High Performance Concrete,UHPC)增强钢筋短搭接RC构件的失效模式与承载力特征。首先阐述了UHPC加固机理,建立了包含活恒荷载效应比、搭接系数m、UHPC强度、混凝土强度、钢筋型号、考虑水平地震作用的弯矩效应比和轴力效应比等关键参数的设计空间;确立分析RC构件承载力可靠度的功能函数,运用Monte Carlo法对设计空间中的关键参数组进行可靠指标计算,然后进行关键参数敏感性分析和计算结果拟合分区。结果表明:设计空间关键参数中,搭接系数、效应比、配筋率、钢筋型号和UHPC强度对可靠指标的影响均显著;UHPC不仅具有良好的承载力增强能力,还能改变失效模式,梁和柱屈服时可靠指标分别提高109.6%和12.9%,屈服时搭接系数分别为0.58和0.57;对于受弯RC梁(压弯柱),m>0.67(0.65)时,钢筋基本能屈服,建议采用UHPC加固;0.50(0.49)

关键词：短搭接 UHPC加固可靠度 Monte Carlo法承载力

Evaluation of Antibiotic Prescribing in the Pediatric Department of Gabriel TouréTeaching Hospital, bamako, mali

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Open Journal of Pediatrics 2024年第3期14卷 645-656页

作者： Pierre Togo Hawa Konaré mariam maïga Karamoko Sacko Djénéba Konaté Abdoul Karim Doumbia Adama Dembélé Oumar Coulibaly Aminata Sangaré Mohamed Elmouloud Cissé Fousseyni Traoré Belco maïga Ibrahim Ahamadou Aminata Doumbia Lala N’Drany Sidibé Amadou Touré Yacouba Aba Coulibaly Kalirou Traoré Tati Simaga Souleymane Sagara Leyla bagna maïga Bory Traoré Abdoul Aziz Diakité Fatoumata Dicko mariam Sylla Sounkalo Dao Boubacar Togo paediatric Department Gabriel Tour&#233 Teaching Hospital Bamako Mali Pediatric Department Distric VI Reference Health Center Bamako Mali Infectious Diseases Department Point G Teaching Hospital Bamako Mali

Objectives: The main objective was to evaluate antibiotic prescribing in the Department of Pediatrics at Gabriel Touré teaching hospital. Methods: This was a prospective descriptive study conducted from September 1 to November 31, 2018, in the Department of Pediatrics at Gabriel Touré teaching hospital. All children aged 0 to 15 years hospitalized for any pathology during the study period and having received at least one antibiotic had been included. Results: We collected 445 children’s records out of 1032 admissions during the study period, representing a hospital frequency of 43.1%. The sex ratio was 1.3%. The 2 - 5 age group accounted for 48.1%. Fever was the reason for consultation in 45.6% of cases. patients’ general condition was altered in 60% of cases. The fathers were blue-collar workers in 65.4% and the mothers housewives in 85%, and had no education in 42.9% and 64.5% respectively. Hepatomegaly was present in 18.2%, splenomegaly in 9.6% and peripheral adenopathy in 3.1%. The site of infection was pulmonary in 37.6% and ENT in 9.2%. bacterial infection was assumed on admission in 54% of cases, and meningitis in 57.7%. The discharge diagnosis was malaria in 54.6%, severe acute malnutrition in 18.6% and meningitis in 6.7%. The death rate was 3.8%. Neutrophilic leukocytosis was present in 47.3% of patients. CRP was positive in 85% of patients. Blood cultures taken in 27.6% of patients were positive in 5. CSF analysis in 30% of patients showed elevated leukocytes in 6.5%. No cultures were positive. Antibiotic prescription was justified by infectious hypotheses in 43.1% of patients. β-lactam antibiotics were prescribed in 98.6%. Antibiotic therapy was not adapted to national/international recommendations in 68.3% of cases, and was not justified in 16.3% of cases on D5 of hospitalization. Conclusion: Antibiotic use was justified in more than half of patients, but remained inadequate in almost two-thirds of cases, in line with national and international recommend

关键词： Antibiotic Prescription Hospitalization Child

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康德自由与自然因果性的相容论论证

哲学动态 2024年第4期 58-69,128页

作者：胡好湖南师范大学中华伦理文明研究中心、湖南师范大学哲学系

在康德哲学中,自由与自然因果性的相容论面临两难:如果自然因果性成立,自由怎么办;如果自由得以可能,自然因果性又怎么办。前一方面的重点是积极自由的可能性论证。既然知性世界和感官世界截然二分,那么无时间的理知原因是否可能产生时... 详细信息

在康德哲学中,自由与自然因果性的相容论面临两难:如果自然因果性成立,自由怎么办;如果自由得以可能,自然因果性又怎么办。前一方面的重点是积极自由的可能性论证。既然知性世界和感官世界截然二分,那么无时间的理知原因是否可能产生时间中的自然结果?这即是异质性难题。对于解决该难题,相较于以往的取消论和转化论,例示说更具优势,它是指,我们能够设想命令这一例子来体现积极自由,由此证成它的可能性。至于后一方面,很少有人注意到,一旦自由得到拯救,它会反过来威胁自然因果性的连续性和必然性。其中,连续性问题可以通过回溯出与理性因果性一致的自然原因来解决,必然性问题则可以通过自由任意选择不同的自然因果序列来解决。由此,康德相容论面临的两难问题能够得到妥善解决。

关键词：决定论异质性连续性必然性

The Novel Long QT Syndrome Type 2-associated F129I Mutation in the KCNH2 Gene Significantly Affects IKr Through the hERG1 Homomeric and Heteromeric Potassium Channels

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Cardiology Discovery 2024年第2期4卷 174-182页

作者： Li Feng Kejuan ma Xin Li Nian Liu deyong Long Changsheng ma Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityNational Clinical Research Center for Cardiovascular DiseasesBeijing 100029China Community Health Service Center of Beijing Nomal University Beijing 100875China.

Objective:The long QT syndrome type 2 is caused by the loss-of-function mutations in the KCNH2 gene,which encodes hERG1,the voltage-gated potassium *** hERG1 channels conduct rapid delayed rectifier K^(+)currents(I_(Kr))in the human cardiac ***2 encodes 2 main isoforms-hERG1a and hERG1b,which assemble to form the homomeric or heteromeric hERG1 ***,the functional characteristics of the heteromeric hERG1 channels in long QT syndrome type 2 are not *** this study,a novel mutation in the N-terminus of hERG1a(F129l)was identified in a proband of long QT syndrome type *** purpose of this study was to identify the electrophysiological change of homomeric and heteromeric hERG1 channels with ***:Candidate genes were screened by direct sequencing.F129l-hERG1a was cloned in the pcDNA3.1 vector by site-directed ***,the wild-type(WT)hERG1a and/or F129l-hERG1a were transiently expressed in the HEK293 cells with or without hERG1b *** expression levels of the transgenes,cellular distribution of hERG1a and hERG1b,and the electrophysiological features of the homomeric and the heteromeric hERG1 channels with the WT-hERG1a or F129l-hERG1a were analyzed using whole-cell patch-clamp electrophysiology,western blotting,and immunofluorescence ***:The proband was clinically diagnosed with long QT syndrome type 2 and carried a heterozygous mutation c.385T>A(F1291)in the KCNH2 *** study proved that the F129l substitution in hERG1a significantly decreased I_(Kr) in both the homomeric and heteromeric hERG1channels by 86%and 70%,respectively(WT-hERG1a(54.88±18.74)pa/pF vs.F129l-hERG1a(7.34±1.90)pa/pF,Ppa/pF vs.F129l-hERG1a/hERG1b(26.54±9.83)pa/pF,P<0.001).The voltage dependence of I_(Kr) activation(V_(1/2) and k)was not affected by the mutation in both the homomeric and heteromeric hERG1 *** peak current densities and the kinetic charact

关键词： Long QT syndrome Arrhythmia lon channels hERG

975 nm multimode semiconductor lasers with high-order Bragg diffraction gratings

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Journal of Semiconductors 2024年第3期45卷 38-44页

作者： Zhenwu Liu Li Zhong Suping Liu Xiaoyu ma National Engineering Research Center for Optoelectronic Devices Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of materials Sciences and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China

The 975 nm multimode diode lasers with high-order surface Bragg diffraction gratings have been simulated and calcu-lated using the 2D finite difference time domain(FDTD)algorithm and the scattering matrix method(SMM).The periods and etch depth of the grating parameters have been optimized.A board area laser diode(ba-LD)with high-order diffraction grat-ings has been designed and *** output powers up to 10.5 W,the measured spectral width of full width at half maxi-mum(FWHM)is less than 0.5 *** results demonstrate that the designed high-order surface gratings can effectively nar-row the spectral width of multimode semiconductor lasers at high output power.

关键词： laser diodes distributed Bragg reflector high order gratings high power laser diodes narrow spectrum width

mass-producible low-cost flexible electronic fabrics for azo dye wastewater treatment by electrocoagulation

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中国化学工程学报:英文版 2023年第7期59卷 222-230页

作者： Chaoyi Yin Jingyuan ma Jian Qiu Ruifang Liu Long ba State Key Laboratory of Bioelectronics School of Biological Science and Medical Engineering Southeast UniversityNanjing 210096China State Key Laboratory of materials-Oriented Chemical Engineering National Engineering Research Center for Special Separation MembraneCollege of Chemical EngineeringNanjing Tech UniversityNanjing 210009China

Electrocoagulation is progressively becoming an ecologically friendly water treatment method owing to its lack of secondary pollution,high active ingredient concentration,high treatment effectiveness,simple equipment,and simplicity of automated control ***,electrocoagulation is offered as a method for treating wastewater containing azo dyes using a revolutionary flexible electronic fabric that can be mass-producible at a reasonable price.A computer-controlled machine embroiders 316L stainless steel fiber(316L SSF)onto an insulating fabric to manufacture a flexible electronic device of cathode and anode with a monopolar arrangement on the fabric *** methyl orange(MO)solution to simulate azo dye wastewater,the decolorization rate of 500 ml MO reached 99.25% under the conditions of 50 mg·L^(-1)initial mass concentration,120 min electrolysis time,15 ma·g^(-1)current density,1 cm electrode spacing,0.1 mol·L^(-1)NaCl,pH 7.6,200 r·min^(-1)rotational speed of the stirrer,and 22-25℃ room *** addition,it is feasible to embroider flexible electronic fabrics with varied sizes and numbers of electrodes based on the amount of treated sewage to increase the degradation rate,which has significant practical application value.

关键词： Flexible electronic fabric 316L Stainless steel fiber Embroidery Electrocoagulation Wastewater treatment