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Direct numerical simulation on relevance of fluctuating velocities and drag reduction in turbulent channel flow with spanwise space-dependent electromagnetic force

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Chinese Physics B 2019年第5期28卷 166-174页

作者： Dai-wen jiang Hui Zhang Bao-Chun Fan An-Hua Wang Science and Technology on Transient Physics Laboratory Nanjing University of Science and Technology

Based on the Fourier–Chebyshev spectral method, the control of turbulent channel flow by space-dependent electromagnetic force and the mechanism of drag reduction are investigated with direct numerical simulation(DNS) methods for different Reynolds numbers. A formula is derived to express the relation between fluctuating velocities and the friction drag coefficient. With the application of electromagnetic force, the in-depth relations among the fluctuating velocities near the wall, Reynolds stress, and the effect of drag reduction for different Reynolds numbers are discussed. The results indicate that the maximum drag reductions can be obtained with an optimal combination of parameters for each case of different Reynolds numbers. The fluctuating velocities along the streamwise and normal directions are suppressed significantly,while the fluctuating velocity along the spanwise direction is enhanced dramatically due to the spanwise electromagnetic force. However, the values of Reynolds stress depend on the fluctuating velocities along the streamwise and normal directions rather than that along the spanwise direction. Therefore, the significant effect of drag reduction is obtained. Moreover,the maximum drag reduction is weakened due to the decay of control effect for fluctuating velocities as the Reynolds number increases.

关键词： flow control turbulent channel flow electromagnetic force direct numerical simulation

Experimental investigation of laser surface processing of flexure silicon nitride ceramic

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中国有色金属学会会刊：英文版 2006年第B2期16卷 558-565页

作者： SUN Li A. P. MALSHE jiang wen-ping P. H. MCCLUSKEY Department of Mechanical Engineering University of Arkansas Fayetteville AR 72701 USA Technology ＆ Solutions Division Caterpillar Inc. Peoria IL 61629 USA

A continuous wave carbon dioxide (CO2) laser (λ=10.6μm) was employed to treat the surface of Si3N4 MOR (modulus of rupture) bars. The effects of the CO2 laser process on physical and mechanical properties of ground Si3N4 samples were investigated. Scanning electron microscopy (SEM) analysis shows that the area occupied by cavities and fracture is decreased by about 49.4% after laser treatments. Cross-sectional metallography results indicate that the secondary YSiAlON phase in the Si3N4 ceramic is softened/melted and flowed into the defects. Four-point bending tests show that the flexural strength of the treated samples is improved to 10.9%. Fractographic analysis show that the fracture origins move from the surface to subsurface. It is concluded that laser surface processing have significant effects on fracture behavior of flexure Si3N4 ceramic.

关键词：氮化硅陶瓷激光表面处理实验研究挠曲强度物理性质

Cross-Target Stance Detection with Sentiments-Aware Hierarchical Attention Network

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Computers, Materials & Continua 2024年第10期81卷 789-807页

作者： Kelan Ren Facheng Yan Honghua Chen wen jiang Bin Wei Mingshu Zhang College of Cryptographic Engineering Engineering University of PAPXi’an710086China

The task of cross-target stance detection faces significant challenges due to the lack of additional background information in emerging knowledge domains and the colloquial nature of language *** stance detection methods often struggle with understanding limited context and have insufficient generalization across diverse sentiments and semantic *** paper focuses on effectively mining and utilizing sentimentsemantics knowledge for stance knowledge transfer and proposes a sentiment-aware hierarchical attention network(SentiHAN)for cross-target stance *** introduces an improved hierarchical attention network designed to maximize the use of high-level representations of targets and texts at various fine-grain *** model integrates phrase-level combinatorial sentiment knowledge to effectively bridge the knowledge gap between known and unknown *** doing so,it enables a comprehensive understanding of stance representations for unknown targets across different sentiments and semantic *** model’s ability to leverage sentimentsemantics knowledge enhances its performance in detecting stances that may not be directly observable from the immediate *** experimental results indicate that SentiHAN significantly outperforms existing benchmark methods in terms of both accuracy and ***,the paper employs ablation studies and visualization techniques to explore the intricate relationship between sentiment and *** analyses further confirm the effectiveness of sentence-level combinatorial sentiment knowledge in improving stance detection capabilities.

关键词： Cross-target stance detection sentiment analysis commentary-level texts hierarchical attention network

Analysis of a reduced-ML algorithm in BLAST

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Science in China(Series F) 2008年第12期51卷 2094-2100页

作者： PAN wen jiang ZhanJun DU ZhengFeng WANG Yan YOU XiaoHu National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

The performance of ML algorithm is much better than other algorithms in the MIMO wireless communication system. However, it is based on the expense of an increase in the complexity. A reduced maximum likelihood （RML） algorithm is proposed in this paper, which derives from the combination of the ML and ZF algorithms. It is shown that the complexity of RML is far lower than that of ML, while in the same performance condition by both theoretic analyses and simulation.

关键词： MIMO BLAST ML

Ginsenoside Rg_3 inhibit hepatocellular carcinoma growth via intrinsic apoptotic pathway

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World Journal of Gastroenterology 2011年第31期17卷 3605-3613页

作者： Jian-wen jiang Xin-Mei Chen Xin-Hua Chen Shu-Sen Zheng The Key Lab of Combined Multi-organ Transplantation Ministry of Public HealthThe Department of Hepatobiliary and Pancreatic SurgeryFirst Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310003Zhejiang ProvinceChina The Department of Pharmacy Shandong Traditional Chinese Medicine UniversityJinan 250355Shandong ProvinceChina

AIM:To investigate the anti-tumor function of ginsenoside Rg3 on hepatocellular carcinoma(HCC) in vitro and in vivo,and its ***:Hep1-6 and HepG2 cells were treated by Rg3 in different concentrations(0,50,100 and 200 μg/mL) in *** incubation for 0,6,12,24 and 48 h,cell viability was measured by 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide *** was identified by terminal deoxynucleotidyl transferasemediated dUTP-biotin nick end ***-3 activity was measured by chromophore p-nitroanilide and flow ***-2 family proteins were ascertained by *** membrane potentialwas detected by 5,5',6' 6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine *** liver tumor-bearing C57Bl6 mice were divided randomly into 4 groups for intra-tumor injection of saline,ginsenoside Rg3,cyclophosphamide(CTX) and ginsenoside Rg3 + CTX ***:The survival time was followed up to 102 *** mice in the Rg3 + CTX group showed significant increased survival time compared with those in the control group(P < 0.05).Rg3 could inhibit HCC cell proliferation and induce cell apoptosis in vitro in the concentration and time dependent *** also induced mitochondria membrane potential to ***-3 activation can be blocked by the inhibitor *** was up-regulated while Bcl-2 and Bcl-XL were down-regulated after Rg3 ***:Our data suggested that Rg3 alone or combined with CTX inhibited tumor growth in vivo and prolonged mouse survival time by inducing HCC cell apoptosis via intrinsic pathway by expression alterations of Bcl-2 family proteins.

关键词： Ginsenoside Rg3 Apoptosis Hepatocellular Carcinoma Bcl-2 family proteins Cyclophosphamide

Acetyl-11-keto-beta-boswellic acid promotes sciatic nerve repair after injury: molecular mechanism

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Neural Regeneration Research 2022年第12期17卷 2778-2784页

作者： Yao Wang Zong-Liang Xiong Xiang-Lin Ma Chong Zhou Mo-Han Huo Xiao-wen jiang wen-Hui Yu Department of Veterinary Medicine Northeast Agricultural UniversityHarbinHeilongjiang ProvinceChina College of Life Sciences Northeast Agricultural UniversityHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Education Department for Common Animal Disease Prevention and Treatment Northeast Agricultural UniversityHarbinHeilongjiang ProvinceChina Institute of Chinese Veterinary Medicine Northeast Agricultural UniversityHarbinHeilongjiang ProvinceChina

Previous studies showed that acetyl-11-keto-beta-boswellic acid(AKBA),the active ingredient in the natural Chinese medicine Boswellia,can stimulate sciatic nerve injury repair via promoting Schwann cell ***,the underlying molecular mechanism remains poorly *** this study,we performed genomic sequencing in a rat model of sciatic nerve crush injury after gastric AKBA administration for 30 *** found that the phagosome pathway was related to AKBA treatment,and brain-derived neurotrophic factor expression in the neurotrophic factor signaling pathway was also highly *** further investigated gene and protein expression changes in the phagosome pathway and neurotrophic factor signaling *** expression in the phagosome pathway was markedly decreased,and brain-derived neurotrophic factor,nerve growth factor,and nerve growth factor receptor expression levels in the neurotrophic factor signaling pathway were greatly ***,expression levels of the inflammatory factors CD68,interleukin-1β,pro-interleukin-1β,and tumor necrosis factor-αwere also *** basic protein-andβ3-tubulin-positive expression as well as the axon diameter-to-total nerve diameter ratio in the injured sciatic nerve were also *** findings suggest that,at the molecular level,AKBA can increase neurotrophic factor expression through inhibiting myeloperoxidase expression and reducing inflammatory reactions,which could promote myelin sheath and axon regeneration in the injured sciatic nerve.

关键词： AKBA axon genomics inflammatory injury and repair myelin sheath myeloperoxidase neurotrophic factor peripheral nerve phagosome pathway regeneration Sprague-Dawley rat

Detection of Internal Leaf Structure Deterioration Using a New Spectral Ratio Index in the Near-Infrared Shoulder Region

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Journal of Integrative Agriculture 2014年第4期13卷 760-769页

作者： LIU Liang-yun HUANG wen-jiang PU Rui-liang WANG Ji-hua Key Laboratory of Digital Earth Science Center for Earth Observation and Digital EarthChinese Academy of Sciences Department of Geography Environmentand PlanningUniversity of South Florida National Engineering Research Center for Information Technology in Agriculture

Spectral reflectance in the near-infrared （NIR） shoulder （750-900 nm） region is affected by internal leaf structure, but it has rarely been investigated. In this study, a dehydration treatment and three paraquat herbicide applications were conducted to explore how spectral reflectance and shape in the NIR shoulder region responded to various stresses. A new spectral ratio index in the NIR shoulder region （NSRI）, defined by a simple ratio of reflectance at 890 nm to reflectance at 780 nm, was proposed for assessing leaf structure deterioration. Firstly, a wavelength-independent increase in spectral reflectance in the NIR shoulder region was observed from the mature leaves with slight dehydration. An increase in spectral slope in the NIR shoulder would be expected only when water stress developed sufficiently to cause severe leaf dehydration resulting in an alteration in cell structure. Secondly, the alteration of leaf cell structure caused by Paraquat herbicide applications resulted in a wavelength-dependent variation of spectral reflectance in the NIR shoulder region. The NSRI in the NIR shoulder region increased significantly under an herbicide application. Although the dehydration process also occurred with the herbicide injury, NSRI is more sensitive to herbicide injury than the water-related indices （water index and normalized difference water index） and normalized difference vegetation index. Finally, the sensitivity of NSRI to stripe rust in winter wheat was examined, yielding a determination coefficient of 0.61, which is more significant than normalized difference vegetation index （NDVI）, water index （WI） and normalized difference water index （NDWI）, with a determination coefficient of 0.45, 0.36 and 0.13, respectively. In this study, all experimental results demonstrated that NSRI will increase with internal leaf structure deterioration, and it is also a sensitive spectral index for herbicide injury or stripe rust in winter wheat.

关键词： spectral ratio index spectral reflectance vegetation index dehydration paraquat herbicide stripe rust

Persistence of gentamicin residues in milk after the intramammary treatment of lactating cows for mastitis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第4期10卷 280-284页

作者： Xun TAN Ye-wen jiang Yi-jun HUANG Song-hua HU Department of Veterinary Medicine Zhejiang University Hangzhou 310029 China

This study was designed to investigate persistence of gentamicin residues in milk after the intramammary treatment of lactating cows for mastitis. Milk samples were collected at a 1-d interval after the last administration from 34 individual cows that had received intramammary infusions of gentamicin. The doses and treatment times evaluated in this study represented those that have been applied by veterinarians in practice. The tetrazolium chloride assay was used to determine whether there were significant residues of the antibiotic in the samples. Persistence of detectable drug residues in milk from 33 cows (28 cows, ≤6 infusions at ≤0.7 g gentamicin; and 5 cows, 2 infusions at 0.8 g gentamicin) did not exceed 5 d; but 1 cow (5 infusions at 0.8 g gentamicin) had detectable residues in its milk for 9 d. Our results suggest that a 5-d milk withdrawal period might be insufficient to secure the clearance of the contamination of gentamicin, because treatment times and dosages contribute to the antibiotic clearance. A larger scale of samples are needed for further investigations.

关键词： Gentamicin Mastitis Intramammary infusion Residue

Improving dehydrogenation properties of Mg/Nb composite films via tuning Nb distributions

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Rare Metals 2017年第7期36卷 574-580页

作者： wen-Cheng Huang Jun Yuan Jin-Guo Zhang jiang-wen Liu Hui Wang Liu-Zhang Ouyang Mei-Qin Zeng Min Zhu Key Laboratory of Advanced Energy Storage Materials of Guangdong Province School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510640China

t To investigate the effect of Nb on the dehydro- genation properties of Mg-Nb composite films, Mg/Nb eight- layer film and Mg- 10 at% Nb alloy film with the similar Mg- to-Nb atomic ratio were prepared by magnetron sputtering. Results show that both Mg/Nb eight-layer film and Mg- 10 at% Nb alloy film exhibit excellent de/hydrogenation properties. Mg- 10 at% Nb alloy film starts to release hydrogen at 108 ℃, and its desorption peak temperature is lower to 146 ℃, which is much better than that of pure MgH2 under the same condi- tion. Scanning electron microscopy （SEM） results demon- strate that the dispersive Nb nanoparticles in Mg/Nb eight- layer film may serve as nucleation sites for Mg ←→ MgH2 reactions, which can provide channels for H diffusion. For Mg- 10 at% Nb alloy film, the uniform distributions of Nb can accelerate the hydrogen diffusion and effectively improve the dehydrogenation kinetics for MgH2. This study provides an enlightening way for designing and preparing Mg-based composite films with excellent dehydrogenation properties.

关键词： Hydrogen storage Mg-Nb Sputtering Thinfilm Kinetics