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A DIRECT SEARCH FRAmE-BASED ADAPTIVE BARZILAI-BORWEIN mETHOD

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Journal of Computational mathematics 2015年第2期33卷 179-190页

作者： Xiaowei Fang Qin ni College of Sciences Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Department of mathematics Huzhou University Huzhou 313000 China

This paper proposes a direct search frame-based adaptive Barzilai-Borwein method for unconstrained minimization. The method is based on the framework of frame-based algorithms proposed by Coope and Price, but we use the strategy of ABB method and the rotational minimal positive basis to reduce the computation work at each iteration. Under some mild assumptions, the convergence of this approach will be established. Through five hundreds and twenty numerical tests using the CUTEr test problem library, we show that the proposed method is promising.

关键词： Direct search Rotational minimal positive basis Adaptive Barzilai-Borweinmethod.

Effects of welding speed on the multiscale residual stresses in frictionstir welded metal matrix composites

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Journal of materials Science & Technology 2019年第5期35卷 824-832页

作者： X.X.Zhang L.H.Wu H.ANDra W.m.Gan m.Hofmann D.Wang D.R.ni B.L.Xiao Z.Y.ma Shenyang National Laboratory for materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Fraunhofer Institute for Industrial mathematics Fraunhofer-Platz 1 Kaiserslautern 67663 Germany German Engineering materials Science Centre Helmholtz-Zentrum Geesthacht D-21502 Geesthacht Germany Heinz maier-Leibnitz Zentrum (mLZ) Technische Universitat Munchen D-85747 Garching Germany

The effects of welding speed on the macroscopic and microscopic residual stresses(RSes) in friction stir welded 17 vol.% SiCp/2009 al-T4 composite plates were studied via neutron diffraction and an improved decoupled hierarchical multiscale modeling methods. measurements showed that the macroscopic and total RSes had the largest variations in the longitudinal direction(LD). Increasing the welding speed led to higher values of measured LD macroscopic and total RSes in the matrix. The welding speed also significantly influenced the distributions and magnitudes of the microscopic RSes. The RSes were predicted via an improved hierarchical multiscale model, which includes a constant coefficient of friction based thermal model. The RSes in the composite plates before friction stir welding(FSW) were computed and then set as the initial states of the FSW process during modeling. This improved decoupled multiscale model provided improved predictions of the temperature and RSes compared with our previous model.

关键词： metal-matrix composites (mmCs) Friction stir welding Residual/internal stress Neutron diffraction Finite element analysis (FEA) multiscale simulation

Sediment-copper distributions in hyper-concentrated turbulent solid-liquid system

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Journal of Environmental Sciences 2007年第1期19卷 123-127页

作者： YANG Jun ni Jin-ren Department of Environmental Engineering Beihang University Beijing 100083 China College of Environmental Sciences Peking University Key Laboratory for Water and Sediment Sciences Ministry of Education Beijing 100871 China

This study presents a special problem on vertical distribution for sediment and copper in hyper-concentrated turbulent solid-liquid system that is essentially different from the ordinary low-concentrated turbulent system. A resonance type turbulent simulation equipment is used for the experimental study in which a vertically uniform turbulent field of the mixture of loess and water is produced in a testing cylinder with a grille stirrer that moves up and down harmoniously with varying vibration frequencies, in order to compare the variations of the vertical profiles of sediment and copper in low- and hyper-concentratod solid-liquid system, different scenarios for input sediment content ranging from 5 to 800 kg/m^3 was considered in the experimental studies. It was found that solids copper content increases with input sediment content, So, and reaches its peak as So goes to 10 kg/m^3 and then decreases rapidly with increasing input sediment content. Such a behavior is possibly resulted from the joint effect of the specific adsorption of copper on loess, precipitation of carbonate and hydroxide of copper due to high carbonate content in the loess and the so-called ＂particulate concentration effect＂ due to the present of the sediment variation in water. The vertical sediment concentration distribution resulted from the uniform turbulence is generally uniform, but slight non-uniformity does occur as sediment concentration exceeds certain value. However, the vertical concentration distributions of soluble copper seem not to be affected much by the variation of sediment concentrations.

关键词： hyper-concentrated system loess copper vertical sediment distribution

Effects of moringa oleifera aqueous extract on the growth performance,blood characteristics,and histological features of gills and livers in nile tilapia

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Aquaculture and Fisheries 2024年第1期9卷 85-92页

作者： mahamoud A.Emam Ramy m.Shourbela waleed N.El-Hawarry Seham Y.Abo-Kora Fatma Abdel-monem Gad Ashraf m.Abd El-latif mahmoud A.O.Dawood Histology Department Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Department of Animal Husbandry and Animal Wealth Development Faculty of Veterinary MedicineAlexandria UniversityAlexandria22758Egypt Pharmacology Department Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Clinical Pathology Department Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Department of Aquatic Animal Diseases and management Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Animal Production Department Faculty of AgricultureKafrelsheikh UniversityKafr El-Sheikh33511Egypt The Center for Applied Research on the Environment and Sustainability The American University in CairoCairo11835Egypt

moringa oleifera is well known as a highly nutritious plant and a water purifier in fish *** fish has many impressive qualities making them very suitable for ***,this study aimed to evaluate the effect of supplementation of moringa oleifera aqueous extract(mOAE)at varying concentrations(0,100,200,and 400 mg/kg diet for 90 days)on growth performance,hematological,and some biochemical parameters of nile ***,histological changes and immunohistochemical expression of caspase 3 in gills and livers were *** enhancements(Pal weight,weight gain,specific growth rate,red blood cells,hemoglobin,packed cell volume,white blood cells,and total serum protein were observed in fish fed 200 mg mOAE/kg diet compared with other ***,a significant reduction(Pnificant changes in lipid profile were *** the other hand,fish fed 400 mg mOAE/kg diet revealed disturbance in the corresponding *** histological degenerative changes were detected in the gills and liver of fish fed 400 mg mOAE/kg *** comparison,fish fed 200 mg mOAE/kg diet showed the best histo-architectures of these organs compared with other *** immune expressions of caspase 3 were determined where gills and liver of fish fed 400 mg mOAE/kg diet revealed extensive number of positive caspase 3 cells indicating severe apoptotic ***,a dietary mOAE at 200 mg/kg diet is recommended to improve the growth performance,hematological parameters,liver and kidney functions in nile ***,caution must be considered when using mOAE at a concentration over 200 mg/kg diet.

关键词： Growth performance Liver Gills moringa oleifera nile tilapia

Isolation and Expression Analysis of Two Genes Encoding Cinnamate 4-Hydroxylase from Cotton(Gossypium hirsutum)

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Journal of Integrative Agriculture 2014年第10期13卷 2102-2112页

作者： ni Zhi-yong LI Bo Neumann m Peter Lü meng FAN Ling Institute of Nuclear and Biological Technologies Xinjiang Academy of Agricultural Sciences College of Agronomy Xinjiang Agricultural University Plant Physiology Laboratory Department of EnvironmentalWater and Agricultural EngineeringFaculty of Civil and Environmental EngineeringTechnion-Israel Institute of Technology

Two genes （GhC4H1 and GhC4H2） that encode putative cotton cinnamate 4-hydroxylases that catalyze the second step in the phenylpropanoid pathway were isolated from developing cotton fibers. GhC4H1 and GhC4H2 each contain open reading frames of 1 518 base pairs （bp） in length and both encode proteins consisting of 505 amino acid residues. They are 90.89% identical to each other at the amino acid sequence level and belong to class I of plant C4Hs. GhC4H1 and GhC4H2 genomic DNA are 2 247 and 2 161 bp long, respectively, and contain two introns located at conserved positions relative to the coding sequence. GhC4HI and GhC4H2 promoters were isolated and found to contain many cis-elements （boxes P, L and AC-1 element） previously identified in the promoters of other phenylpropanoid pathway genes. Histochemical staining showed GUS expression driven by the GhC4H1 and GhC4H2 promoters in ovules and fibers tissues. GhC4H1 and GhC4H2 were also widely expressed in other cotton tissues. GhC4H2 expression reached its highest level during the elongation stage of fiber development, whereas GhC4H1 expression increased during the secondary wall development period in cotton fibers. Our results contribute to a better understanding of the biochemical role of GhC4H1 and GhC4H2 in cotton fiber development.

关键词： cinnamate 4-hydroxylase Gossypium hirsutum promoter analysis phenylpropanoid pathway

Changing patterns of urban-rural nutrient flows in China:driving forces and options

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Science Bulletin 2017年第2期62卷 83-91页

作者： Chaoqing Yu Yuchen Xiao Shaoqiang ni Department of Earth System Science Ministry of Education Key Laboratory for Earth System Modeling Tsinghua University Beijing 100084 China

Nutrient recycling has been practiced for thousands of years in China to maintain food production without environmental pollution. In the past three decades, however, the traditional nutrient recycling systems have been replaced with waste treatment systems, which have resulted in rapid and severe environmental pollution. By analyzing the primary driving forces of the changing nutrient flows(technology, labor costs, food supplies, fertilizer demands, environmental quality, human health, and public awareness), this paper argues that technology fundamentally motivated the nutrient-recycling strategy to address the malnutrition problem in traditional societies but has constrained the reconstruction of nutrient recycling systems in modern cities. With the availability of synthetic fertilizers in modern society, the lack of interdisciplinary views in policy making for nutrient management is the root cause of today's environmental situation. Ongoing fast urbanization has concentrated more nutrients in urban areas, creating the need for a national nutrient management plan to coordinate multiple ministries and fix the uncoupled nutrient cycling between urban and rural systems. Rebuilding the traditional nutrient-recycling systems is an environmentally and economically effective solution. There are three fundamental technological barriers to reconstructing the nutrient recycling systems, as follows: userfriendly toilets, the separation of sewage pipelines, and easy-to-use organic fertilizers made from human manure or other organic waste. Overcoming these barriers requires building institutional mechanisms,developing the necessary infrastructure, creating research funding, and providing open experimental platforms for technological development.

关键词：养分循环驱动力变化规律流动中国废物处理系统营养循环技术壁垒

Enhancing plant-microbe associated bioremediation of phenanthrene and pyrene contaminated soil by SDBS-Tween 80 mixed surfactants

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Journal of Environmental Sciences 2014年第5期26卷 1071-1079页

作者： Hewei ni Wenjun Zhou Lizhong Zhu Department of Environmental Science Zhejiang University Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control

The use of surfactants to enhance plant-microbe associated dissipation in soils contaminated with polycyclic aromatic hydrocarbons （PAHs） is a promising bioremediation technology. This comparative study was conducted on the effects of plant-microbe treatment on the removal of phenanthrene and pyrene from contaminated soil, in the presence of low concentration single anionic, nonionic and anionic-nonionic mixed surfactants. Sodium dodecyl benzene sulfonate （SDBS） and Tween 80 were chosen as representative anionic and nonionic surfactants, respectively. We found that mixed surfactants with concentrations less than 150 mg/kg were more effective in promoting plant-microbe associated bioremediation than the same amount of single surfactants. Only about （m/m） of mixed surfactants was needed to remove the same amount of phenanthrene and pyrene from either the planted or unplanted soils, when compared to Tween 80. mixed surfactants （〈 150 mg/kg） better enhanced the degradation efficiency of phenanthrene and pyrene via microbe or plant-microbe routes in the soils. In the concentration range of 60-150 mg/kg, both ryegrass roots and shoots could accumulate 2-3 times the phenanthrene and pyrene with mixed surfactants than with Tween 80. These results may be explained by the lower sorption loss and reduced inteffacial tension of mixed surfactants relative to Tween 80, which enhanced the bioavailability of PAHs in soil and the microbial degradation efficiency. The higher remediation efficiency of low dosage SDBS-Tween 80 mixed surfactants thus advanced the technology of surfactant-enhanced plant-microbe associated bioremediation.

关键词： polycyclic aromatic hydrocarbons contaminated soil plant-microbe associated bioremediation ryegrass

ABRUPT DEFLECTED SUPERCRITICal WATER FLOW-REVISED THEORY OF SHOCK WAVE

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Journal of Hydrodynamics 2006年第1期18卷 32-39页

作者： ni Han-gen LIU Ya-kun State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

The shock wave angle and depth ratio of the abrupt deflected supercritical water flow due to deflector was investigated experimentally and theoretically. A correction coefficient of the hydro-dynamic pressure ξ was introduced to generalize the momentum equation in the perpendicular direction to the shock front. An extensive series of tests were conducted in a 1 m wide flume with the Froude number ranging from 1.70 to 8.37, the deflection angle ranging from 5° to 40° and the length of deflector ranging from 0.28 m to 1 m. A dimensionless parameter K was defined to depict the ratio of the flow height to flow thickness. Test results show that the val ue of ~, the correction coefficient of the non-hydrostatic pres- sure distribution, decreases with the increase of the value of K An empirical relationship between the value of ξ and the val ue of K was proposed. It is indicated that the relative errors of the results calculated by the revised theory is much smaller than that obtained from the Ippen theory. Finally, a simple explicit expression was suggested to calculate the shock wave height ratio in consideration of the effect of the non-hydrostatic pressure distribution.

关键词： theory of shock wave abrupt deflection of supercritical flow trajectory type energy dissipater

直肠骶骨筋膜的临床和尸体标本解剖观察及其临床意义

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中华胃肠外科杂志 2020年第7期23卷 689-694页

作者：王枭杰 waleed m.Ghareeb 池畔黄颖福建医科大学附属协和医院结直肠外科福州350001

目的熟悉直肠骶骨筋膜形态及走行,对于在全直肠系膜切除术(TmE)中,保证直肠系膜完整性及保护自主神经盆丛至关重要,但目前尚缺乏对直肠骶骨筋膜的全面完整描述。本文通过高清腹腔镜或机器人TmE中的临床观察和尸体标本解剖,对直肠骶骨筋... 详细信息

目的熟悉直肠骶骨筋膜形态及走行,对于在全直肠系膜切除术(TmE)中,保证直肠系膜完整性及保护自主神经盆丛至关重要,但目前尚缺乏对直肠骶骨筋膜的全面完整描述。本文通过高清腹腔镜或机器人TmE中的临床观察和尸体标本解剖,对直肠骶骨筋膜形态及走行进行观察总结,并讨论该区域的最佳游离路径。方法采用描述性病例系列研究方法,回顾性分析2018年1—12月期间就诊于福建医科大学附属协和医院结直肠外科的127例直肠癌患者的临床病理资料和手术录像,及同期科室数码数据库的20例TmE术后直肠标本的高清照片,同时纳入来源于福建医科大学解剖学教研室的28例人体尸体标本,观察直肠骶骨筋膜形态和移行情况。结果(1)总结手术录像提示,127例患者均可观察到直肠骶骨筋膜从后方呈水平弧形附着于直肠固有筋膜,形成融合筋膜。融合区域无法直接分离,如不离断,则容易破坏直肠固有筋膜。离断后,沿着直肠后方直肠骶骨筋膜附着缘向右侧观察,见该水平以下右侧间隙下半部仍为融合筋膜,该融合筋膜在侧方上半部重新分开为直肠固有筋膜与腹下神经前筋膜,该分开处的腹下神经前筋膜为侧方间隙分离时的刚性障碍。沿着其分开处逐步切断该筋膜,可见由右骶(S)2~S4发出的盆丛被灰白色腹下神经前筋膜覆盖,观察到该筋膜与Denonvilliers筋膜前间隙已被切断的Denonvilliers筋膜前叶相延续;而内侧的直肠固有筋膜仍完整。右侧直肠骶骨筋膜附着缘从后上向前下斜行走行。左侧直肠骶骨筋膜形态与右侧对称。(2)观察28例半骨盆尸体标本发现,于S4椎体下缘水平,腹下神经前筋膜向前与直肠固有筋膜融合成直肠骶骨筋膜。向直肠右侧间隙进行分离,逐步切断直肠骶骨筋膜的右侧附着缘,见直肠骶骨筋膜附着缘从后上走行至前下,呈斜行走向。附着缘向头侧移行为腹下神经前筋膜,向前移行为Denonvilliers筋膜前叶。盆丛在前侧方发出多支细小直肠支,呈束状穿过腹下神经前筋膜和Denonvilliers筋膜前叶的相互移行区,支配直肠。(3)对20例TmE标本进行观察,见后方直肠骶骨筋膜附着缘围绕着直肠系膜呈弧形,两侧附着缘呈斜行。后方和两侧附着缘后下方的直肠系膜被直肠骶骨筋膜包绕,附着缘水平的前上方直肠系膜被直肠固有筋膜包绕。结论结合直肠骶骨筋膜形态学特点,术中应于S4椎体水平在直肠后方弧形切断直肠骶骨筋膜,从直肠后间隙进入肛提肌上间隙;进行两侧间隙分离前应先行直肠前方间隙的分离,倒"U"型切断Denonvilliers筋膜前叶,沿着Denonvilliers筋膜后间隙从上向下分离侧前方间隙,最后切断直肠骶骨筋膜的两侧附着缘,方可保证直肠侧方筋膜的完整,且并不损伤盆丛分支与神经血管束。

关键词：直肠骶骨筋膜直肠固有筋膜解剖学活体解剖尸体解剖