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Cleavage of catalytic ally grown carbon nanofibers into hydrophilic segments by oxidation in a mixture of concentrated HNO3-H2SO4 in an autoclave

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Journal of Coal Science & Engineering(China) 2012年第2期18卷 188-190页

作者： TENG Li-hua wang zhi-jiang TANG Tian-di School of Biology and Environmental Science Zhejiang Wanli UniversityNingbo 315100China College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035China

The catalytically grown carbon nanofibers were treated by a mixture of concentrated nitric aid and sulfuric aid in an autoclave at temperature 333, 363 and 423 K. It was found that the samples treated at 363 K and 423 K were still well dispersed in water 15 hours later, indicating that carbon nanofibers can be made hydrophilicy. It was also found that the dispersion was destroyed when the pH value was lowered by adding acid. The results are significant when the carbon nanofibers are used as enhancing component in polymer composite material because several hundreds of nm are perfect size and the hydrophilicity controls the dispersion of CNFs in the polymer media. It is concluded that the amount of the oxygen-containing groups on the surface and the hydrophilicity of the carbon nanofibers can be controlled by the treatment temperature, and that the carbon nanofibers can be cleaved into uniform segments.

关键词： catalytically grown carbon nanofibers carbon nanotubes oxidation

Generation of Radial Electric Field with Electrode Biasing

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Chinese Physics Letters 2001年第2期18卷 257-259页

作者： wang Cheng PAN Ge-Sheng WEN Yi-zhi YU Chang-Xuan WAN Shu-De LIU Wan-Dong wang zhi-jiang SUN Xuan Department of Modern Physics University of Science and Technology of ChinaHefei 230027

Time and space resolved measurements of the radial electric field(Er)have been conducted during the electrode biasing experiments on the KT-5C *** suppression of the turbulent transport with the change of Er induced by the biased electrode is *** is found that the poloidal flow contributes to the main part of the Er,and the change of the poloidal flow has a lead of about 20μs to the formation of *** observations suggest that a radial current,responding to an induced voltage on the electrode,drives a poloidal flow which in turn drives the radial electric field.

关键词： flow tokamak electrode

Goal-Programming Model Based on the Utility Function of the Decision-maker

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Journal of Systems Science and Systems Engineering 2001年第4期13卷 497-503页

作者： wang zhi--jiang School of Economics &. Management, Huaqiao University, Quanzhou 362011, China School of Economics & Management Huaqiao UniversityQuanzhou 362011 China

Based on the analysis of the problems in traditional GP model, this paper provides the model with the utility function of the decision-maker and compares this model with the one presented in reference article [1].

关键词： GP mode1 utility function criterion function

CREATING OPPORTUNITTIES FOR STUDENTS TO SPEAK

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Chinese Journal of Applied Linguistics 1997年第1期20卷 61-69页

作者： wang zhi jiang Tangshan Institute of Technology

The Neglect Of SpeakingSpeaking is commonly neglected in classrooms in *** students can do quite well inexaminations,but they can not answer very simple questions in *** problem is serious andit demands urgent attention and immediate *** this essay I will illustrate how the problem can besolved in detail.I will do this by suggesting some speaking activities.

关键词：月池

Intravitreal bevacizumab with or without triamcinolone acetonide for diabetic macular edema： a meta-analysis of randomized controlled trials

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Chinese Medical Journal 2014年第19期127卷 3471-3476页

作者： Liu Xiangdong Zhou Xiaodong wang zhi Li Tao jiang Bo Department of Ophthalmology Jinshan Hospital Fudan UniversityShanghai 201508 China

Background Intravitreal anti-vascular endothelial growth factor （anti-VEGF） drugs and corticosteroids are being widely used to treat diabetic macular edema （DME）. The purpose of this study was to evaluate further the efficacy and safety of intravitreal bevacizumab （IVB） alone in comparison with intravitreal bevacizumab combined with triamcinolone acetonide （IVB/IVT） in the treatment of DME. Methods Pertinent publications were identified through CNKI, PubMed, Medline, EMBASE, and the Cochrane Controlled Trials Register up to November 30, 2013. Two investigators independently assessed the quality of the trials, and changes in central macular thickness （CMT） and best-corrected visual acuity （BCVA） were extracted at 6 weeks and 3, 6, 12, and 24 months after the initial treatment. A meta-analysis was carried out to compare the results between the groups receiving IVB and IVB/IVT using the software RevMan 5.0. Results A total of six randomized controlled trials （RCTs） were identified and included. The meta-analysis revealed that a significant reduction of the CMT was observed at 3 months after the initial treatment in the IVB/IVT group compared to the IVB group （P=-0.001）. Also, changes in CMT at 6 weeks and 6, 12, and 24 months did not vary significantly between the IVB and IVB/IVT groups （P=0.53, 0.76, 0.34, and 0.09, respectively）. Similarly, changes in BCVA at 6 weeks and 3, 6, 12, and 24 months also did not vary significantly between the two groups （P=-0.66, 0.98, 0.81, 0.07, and 0.80, respectively）. The results were robust to sensitivity analyses. However, the rate of intraocular pressure （IOP） rise after intravitreal injections varied significantly between the IVB and IVB/IV＇r groups （P 〈0.01）. A publication bias was not detected by funnel plots, the Egger method, or the Begg method. Conclusions Results of this meta-analysis showed that the treatments with IVB alone and combined IVB/IVT were similarly effective in improving the visual acuity, and, to some degree; c

关键词： intravitreal injection bevacizumab triamcinolone acetonide diabetic macular edema meta-analysis

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相关产品的最优价格调整策略

系统工程理论与实践 2000年第1期20卷 36-40页

作者：王志江华侨大学管理信息科学系福建泉州362011

根据企业销售收入最大化和利润最大化两个不同目标,利用需求价格弹性、需求交叉弹性的概念,提出了相关产品价格调整的数学模型,并结合具体实例研究计算.

关键词：需求价格弹性需求交叉弹性相关产品企业

Surface micro-arrays enhancing electromagnetic interference shielding of polydimethylsiloxane/multiwalled carbon nanotubes nanocomposites

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Nano Research 2025年第1期18卷 508-519页

作者： Ke jiang zhi Chen Ji Yu Chen Zheng Shan Huang Ming wang Chongqing Key Laboratory of Soft-Matter Material Manufacturing School of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China School of Mechanics Civil Engineering and ArchitecturesNorthwestern Polytechnical UniversityXi’an 710072China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Herein,the electromagnetic shielding performance of surface concave-convex(SC)and zig-zag micro-arrays was studied by using a simulation prediction and a three-dimensional(3D)printing custom ***,surface stripe concaveconvex(SSC)and surface cylindrical concave-convex(SCC)micro-arrays with or without zig-zag micro-arrays are designed,and their shielding performance is simulated in multi-bands(C-,X-band).The multiwalled carbon nanotubes/polydimethylsiloxane composites(MWCNT/PDMS)with different SC structures and different electrical conductivity are molded in acrylonitrile-butadiene-styrene copolymer(ABS)molds which are printed by a 3D *** results show that the electromagnetic interference shielding effectiveness(EMI SE)of the samples can be enhanced by constructing the SC micro-arrays with zig-zag micro-arrays,and improving with the increase of conductivity and *** addition,the shielding mechanism of the SC-MWCNT/PDMS composites is investigated and discussed by an electromagnetic simulation.

关键词： surface micro-arrays electrical properties electromagnetic interference(EMI)shielding three-dimensional(3D)printing

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需求变动下企业产品价格的动态调整

系统工程理论与实践 2000年第4期20卷 70-73页

作者：王志江华侨大学管理信息科学系福建泉州362011

在市场经济条件下 ,企业必须随时根据市场对企业产品的需求变动情况调整产品的价格 ,以实现企业既定的经营目标 .本文在假定企业产品需求曲线为线性以及边际成本为常数的条件下 ,按照销售收入最大化和利润最大化两个目标 ,分别提出了相... 详细信息

在市场经济条件下 ,企业必须随时根据市场对企业产品的需求变动情况调整产品的价格 ,以实现企业既定的经营目标 .本文在假定企业产品需求曲线为线性以及边际成本为常数的条件下 ,按照销售收入最大化和利润最大化两个目标 ,分别提出了相应的价格调整公式 ,并结合具体算例予以说明 .

关键词：需求变动需求曲线产品价格市场经济企业

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai wang Shao-jiang wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes