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FUNDAMENTAL SOLUTION BASED GRADED ELEMENT MODEL FOR STEADY-STATE HEAT TRANSFER IN FGM

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Acta Mechanica Solida Sinica 2012年第4期25卷 377-392页

作者： Leilei cao Hui wang qing-hua Qi Key Laboratory for Highway Construction Technology and Equipment of Ministry of Education Chang'an University Xi'an 710064 China School of Engineering Australian National University canberra ACT 0200 Australia College of Civil Engineering and Architecture Henan University of Technology Zhengzhou 450052 China

A novel hybrid graded element model is developed in this paper for investigating thermal behavior of functionally graded materials （FGMs）. The model can handle a spatially varying material property field of FGMs. In the proposed approach, a new variational functional is first constructed for generating corresponding finite element model. Then, a graded element is formulated based on two sets of independent temperature fields. One is known as intra-element temperature field defined within the element domain; the other is the so-called frame field defined on the element boundary only. The intra-element temperature field is constructed using the linear combination of fundamental solutions, while the independent frame field is separately used as the boundary interpolation functions of the element to ensure the field continuity over the interelement boundary. Due to the properties of fundamental solutions, the domain integrals appearing in the variational functional can be converted into boundary integrals which can significantly simplify the calculation of generalized element stiffness matrix. The proposed model can simulate the graded material properties naturally due to the use of the graded element in the finite element （FE） model. Moreover, it inherits all the advantages of the hybrid Trefftz finite element method （HT-FEM） over the conventional FEM and boundary element method （BEM）. Finally, several examples are presented to assess the performance of the proposed method, and the obtained numerical results show a good numerical accuracy.

关键词： graded element hybrid FEM heat conduction functionally graded materials

Electrochemical Degradation of o-Chloronitrobenzene by Three-dimensional Electrodes

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Chemical Research in Chinese Universities 2012年第5期28卷 891-896页

作者： MENG qing-han wang jing LIU Ling cao Bing College of Materials Science and Engineering Beijing University of Chemical TechnologyBeo'ing 100029P.R.China

Degradation of o-chloronitrobenzene wastewater was experimentally investigated at a three-dimensional electrode（TDE） with granular activated carbon as the particle electrode, graphite as the anode, and stainless steel plate as the cathode. The kinetic model of o-chloronitrobenzene degradation was studied, and the effects of pH, electrolysis time, particle electrode, electrolyte concentration, and initial concentration of the solution on degradation efficiency were investigated to determine the optimal operating conditions. The degradation of o-chloronitrobenzene by oxidation at the TDE was monitored by chemical oxygen demand（COD） measurements, UV-Vis absorption, and high performance liquid chromatography（HPLC）. COD degradation by electrochemical degradation followed pseudo-first order kinetics with respect to the concentration of o-chloronitrobenzene solutions. Optimal reaction conditions included 15 g of activated carbon as the particle electrode, 400 mg/L o-chloronitrobenzene solution containing 0.10 mol/L Na2SO4, pH=3, and 60 min of electrolysis. The UV-Vis absorption spectra and HPLC results illustrate that the benzene ring in o-chloronitrobenzene was rapidly broken down to form aliphatic substances through electrochemical degradation. COD degradation was approximately 98.5% at optimal conditions.

关键词： Three-dimensional electrode Electrochemical oxidation o-Chloronitrobenzene

Construction of continuous heat conductive channel,a double harvest strategy to enhance thermal conductance and bending strength of C/SiC composites

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Journal of Materials Science & Technology 2022年第10期105卷 101-108页

作者： Yunhai Zhang Yongsheng Liu Liyang cao Xutong Zheng Yejie cao jing wang qing Zhang Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China

The development of efficient and quick method to prepare structure-function integrative C/SiC composites is always a major challenge in this ***,the thermal conductivity and bending strength of C/SiC composites were enhanced simultaneously via continuous high heat conductive channels constructed by continuous wave laser machining and pitch-based high thermal conductivity carbon fber in thickness *** revealed that the thermal conductivity of the modifed C/SiC composites is three times higher than that of referential C/SiC composites due to its highly ordered heat conducive channel in the thickness ***,the bending strength of modifed C/SiC composites increased to *** better understand the enhance mechanism,the micro-structure for both the composites and heat conductive channel was systematically *** results demonstrated that the rivet effect of heat conductive channel and the formed two phases structure on the fbers dispersed partial of load and fnally enhanced the property of the *** a word,this method holds a nice applicable future in constructing structure-function integrative C/SiC composites.

关键词： C/SiC composites Structure-function integrative Thermal conductivity Bending strength Heat conductive channel

Dexmedetomidine as an adjunct to peripheral nerve blocks in pediatric patients

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World Journal of Pediatrics 2022年第4期18卷 251-262页

作者： jing Yang Yu Cui Rong cao qing-hua huang Qian-Qian Zhang Department of Anesthesiology The Affiliated HospitalSchool of MedicineUESTC Chengdu Women’s&Children’s Central HospitalNo.1617Riyue AvenueQingyang DistrictChengdu 610091China

Background Combining local anesthetics with dexmedetomidine(DEX)for nerve blocks has been tested and confirmed as an alternative technique to strengthen analgesia in adults,but the evidence supported this proposal in pediatrics was not convincing ***,we intend to conduct a meta-analysis to make an appraisal of the effects of DEX as a local anesthetic adjuvant on peripheral nerve blocks in *** The analysis has been registered on https://***/prospero/with the registration number CRD42021254029 on June 10th,***,Ovid MEDLINE,Embase and Cochrane central register were searched for the randomized controlled trials(RCTs)that are relevant to child/pain/DEX or block up to April 30,*** Eight RCTs were included for data *** pooled results showed a significantly reduced number of patients who required postoperative analgesics within DEX groups[odds ratio=0.1,95%confidence interval(CI)0.03-0.32,P<0.001].And DEX significantly prolonged the duration of analgesia of local anesthetics in the meantime[standardized mean difference(SMD)=4.93,95%CI 3.02-6.83,P<0.001].Nevertheless,adding DEX as an adjunct to local anesthetics would significantly decrease heart rate(SMD=-0.95,95%CI-1.45 to-0.45,P<0.001)and increase sedation score(SMD=1.6,95%CI 0.53-2.66,P=0.003)*** Adding DEX as an adjunct to peripheral nerve blocks can prolong analgesia until postoperative 8 hours in pediatric ***,the benefits should be weighed against the increasing risk of bradycardia and sedation in critical children.

关键词： Block Child Dexmedetomidine Pain

Recent progress in porous Mg-based foam preparation approaches:effect of processing parameters on structure and mechanical property

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Journal of Iron and Steel Research International 2022年第3期29卷 371-402页

作者： Solomon-Oshioke Agbedor Dong-hui Yang jing cao Jian-qing Chen Bassiouny Saleh Chao Qiu Lei wang jing-hua Jiang Ai-bin Ma College of Mechanics and Materials Hohai UniversityNanjing211100JiangsuChina Suqian Research Institute of Hohai University Suqian223814JiangsuChina Ocean and Offshore Engineering Research Institute of Hohai University Nantong226019JiangsuChina

Porous metals are a class of cellular materials with lightweight and unique mechanical,electrical,thermal,physical and acoustic *** and magnesium alloy foams have exhibited excellent *** particular,open-cell Mg-based foams(porous Mg/Mg alloy foams)have been used for bioresorbable implants,CO_(2)trapping systems,filters,heat exchangers,absorbent panels and many other *** significant progress has been taken in producing porous Mg-based foams with good structure-property relations,but with a large number of different processing parameters,different mechanical properties and pore morphologies of each porous Mg-based foam,it is essential to understand the individual effects of each aspect of the ***,the present article summarized the effects of available processing parameters on the structure and mechanical properties of the porous Mg-based ***,the future perspectives to enhance the structure and properties of porous Mg/Mg alloy foams were discussed.

关键词： Porous Mg alloy Powder processing Sintering Liquid metal infiltration Mechanical property

Measles,mumps,and rubella revaccination in children after completion of chemotherapy and hematopoietic stem cell transplantation:a single-center prospective efficacy and safety analysis

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World Journal of Pediatrics 2023年第11期19卷 1062-1070页

作者： Min wang qing Yuan Peng-Fei Deng Yi Fei hua Zhang Fen Zhou Wen-Juan Chen qing cao jing Chen Yi-Jin Gao Department of Hematology and Oncology Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityNo.1678 Dongfang RoadPudong DistrictShanghai200127China Center for Diseases Control and Prevention Fudan University Pudong Institute of Preventive MedicineShanghai200136China Department of Infectious Diseases Shanghai Children’s Medical CenterShanghai Jiao Tong University School of MedicineShanghaiChina

Background Chemotherapy and hematopoietic stem cell transplantation(HSCT)can damage the immune system,and may result in a loss of protection from infectious *** study aimed to evaluate the impact of these treatments on the decrease in antibody titers of the measles,mumps,and rubella(MMR)vaccine and seroconversion post-revaccination of *** After completion of treatment for primary diseases,participants received an MMR *** titers for MMR before revaccination were analyzed for all 110 *** revaccination,68 participants received a follow-up evaluation of antibody titer and adverse *** Multivariable analysis showed that therapeutic schedules were the only factor correlated with lack of antibody titers for measles after completing treatment(P=0.008),while for mumps and rubella,no statistically significant difference was ***,our study clearly demonstrated positive seroconversion rates for measles(97.5%),mumps(81.0%),and rubella(93.2%),with antibody levels rising across the board and peaking at around 6 months following ***,6 months after revaccination,a downtrend of antibody titer levels was observed,which is comparatively earlier than the waning immunity observed in healthy ***,we found MMR revaccination to be safe,with only a single adverse reaction(local pain at the injection site)*** MMR revaccination is immunogenic for the *** suggest periodic monitoring of antibody titers,in addition to a booster vaccination,although the optimal timing of booster vaccination remains to be investigated further.

关键词： Adjuvant Chemotherapy Children Hematopoietic stem cell transplantation Immunogenicity Mumps-measles-rubella.Vaccine

A hyaluronic acid granular hydrogel nerve guidance conduit promotes regeneration and functional recovery of injured sciatic nerves in rats

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Neural Regeneration Research 2023年第3期18卷 657-663页

作者： Jie Yang Chia-Chen Hsu Ting-Ting cao hua Ye jing Chen Yun-qing Li Institute of Medical Research Northwestern Polytechnical UniversityXi’anShaanxi ProvinceChina Institute of Biomedical Engineering Department of Engineering ScienceUniversity of OxfordOxfordUK The Oxford Suzhou Centre for Advanced Research(OSCAR) SuzhouJiangsu ProvinceChina Department of Anatomy Histology and Embryology&K.K.Leung Brain Research CentreThe Fourth Military Medical UniversityXi’anShaanxi ProvinceChina Key Laboratory of Brain Science Research and Transformation in Tropical Environment of Hainan Province Hainan Medical UniversityHaikouHainan ProvinceChina Department of Anatomy College of Basic Medical SciencesDali UniversityDaliYunnan ProvinceChina

A hyaluronic acid granular hydrogel can promote neuronal and astrocyte colony formation and axonal extension in vitro,suggesting that the hydrogel can simulate an extracellular matrix structure to promote neural ***,in vivo experiments have not been *** this study,we transplanted a hyaluronic acid granular hydrogel nerve guidance conduit to repair a 10-mm long sciatic nerve *** Basso,Beattie,and Bresnahan locomotor rating scale,sciatic nerve compound muscle action potential recording,Fluoro-Gold retrograde tracing,growth related protein 43/S100 immunofluorescence staining,transmission electron microscopy,gastrocnemius muscle dry/wet weight ratio,and Masson’s trichrome staining results showed that the nerve guidance conduit exhibited similar regeneration of sciatic nerve axons and myelin sheath,and recovery of the electrophysiological function and motor function as autologous nerve *** conduit results were superior to those of a bulk hydrogel or silicone tube *** findings suggest that tissue-engineered nerve conduits containing hyaluronic acid granular hydrogels effectively promote the morphological and functional recovery of the injured sciatic *** nerve conduits have the potential as a material for repairing peripheral nerve defects.

关键词： functional recovery granular hydrogel hyaluronic acid myelin sheath nerve conduit nerve regeneration peripheral nerve regeneration sciatic nerve injury tissue engineering transection injury

A novel Fe(OH)3/TiO2 nanoparticles and its high photocatalytic activity

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Chinese Chemical Letters 2007年第10期18卷 1261-1264页

作者： Nan wang Li hua Zhu jing Li He qing Tang Department of Chemistry and Chemical Engineering Hubei Key Lab of Bioinorganic Chemistry and Materia Medica Huazhong University of Science and Technology Wuhan 430074 China

A very simple and controllable approach was proposed to synthesize novel Fe（OH）3/TiO2 nanoparticles. Compared with neat TiO2, the Fe（OH）3/TiO2 increased the rate of the photocatalytic degradation of methyl orange at pH 6.0 by more than five times, showing photocatalytic activity as excellent as P25. This enhancing effect is mainly attributed to the ferric hydroxide deposits as the electron scavenger and the enriched surface hydroxyl groups.

关键词： Titanium dioxide Surface modification Ferric hydroxide Photocatalysis

Antioxidant activity of polyaniline nanofibers

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Chinese Chemical Letters 2007年第8期18卷 1005-1008页

作者： Jia wang Li hua Zhu jing Li He qing Tang Department of Chemistry and Chemical Engineering Hubei Key laboratory of Bioinorganic Chemistry and Materia Medica Huazhong University of Science and Technology Wuhan 430074 China

Well-confined uniform polyaniline （PANI） nanofibers were synthesized by using photo-assisted chemical oxidative polymer- ization of aniline in the presence of different dopant acids, and the radical scavenging ability of the produced PANI nanofibers was determined by the DPPH assay. It was found that the antioxidant activity of PANI nanofibers was higher than conventional PANI, and increased with decreasing of averaged diameter of the nanofibers. The enhanced antioxidant activity was concerned with increased surface area of PANI nanofibers.

关键词： Polyaniline nanofibers Dopant acids Antioxidant activity DPPH radical